| /* vi: set sw=4 ts=4: */ |
| /* |
| * sh.c -- a prototype Bourne shell grammar parser |
| * Intended to follow the original Thompson and Ritchie |
| * "small and simple is beautiful" philosophy, which |
| * incidentally is a good match to today's BusyBox. |
| * |
| * Copyright (C) 2000,2001 Larry Doolittle <larry@doolittle.boa.org> |
| * |
| * Credits: |
| * The parser routines proper are all original material, first |
| * written Dec 2000 and Jan 2001 by Larry Doolittle. The |
| * execution engine, the builtins, and much of the underlying |
| * support has been adapted from busybox-0.49pre's lash, which is |
| * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org> |
| * written by Erik Andersen <andersen@codepoet.org>. That, in turn, |
| * is based in part on ladsh.c, by Michael K. Johnson and Erik W. |
| * Troan, which they placed in the public domain. I don't know |
| * how much of the Johnson/Troan code has survived the repeated |
| * rewrites. |
| * |
| * Other credits: |
| * b_addchr() derived from similar w_addchar function in glibc-2.2 |
| * setup_redirect(), redirect_opt_num(), and big chunks of main() |
| * and many builtins derived from contributions by Erik Andersen |
| * miscellaneous bugfixes from Matt Kraai |
| * |
| * There are two big (and related) architecture differences between |
| * this parser and the lash parser. One is that this version is |
| * actually designed from the ground up to understand nearly all |
| * of the Bourne grammar. The second, consequential change is that |
| * the parser and input reader have been turned inside out. Now, |
| * the parser is in control, and asks for input as needed. The old |
| * way had the input reader in control, and it asked for parsing to |
| * take place as needed. The new way makes it much easier to properly |
| * handle the recursion implicit in the various substitutions, especially |
| * across continuation lines. |
| * |
| * Bash grammar not implemented: (how many of these were in original sh?) |
| * $_ |
| * ! negation operator for pipes |
| * &> and >& redirection of stdout+stderr |
| * Brace Expansion |
| * Tilde Expansion |
| * fancy forms of Parameter Expansion |
| * aliases |
| * Arithmetic Expansion |
| * <(list) and >(list) Process Substitution |
| * reserved words: case, esac, select, function |
| * Here Documents ( << word ) |
| * Functions |
| * Major bugs: |
| * job handling woefully incomplete and buggy (improved --vda) |
| * reserved word execution woefully incomplete and buggy |
| * to-do: |
| * port selected bugfixes from post-0.49 busybox lash - done? |
| * finish implementing reserved words: for, while, until, do, done |
| * change { and } from special chars to reserved words |
| * builtins: break, continue, eval, return, set, trap, ulimit |
| * test magic exec |
| * handle children going into background |
| * clean up recognition of null pipes |
| * check setting of global_argc and global_argv |
| * control-C handling, probably with longjmp |
| * follow IFS rules more precisely, including update semantics |
| * figure out what to do with backslash-newline |
| * explain why we use signal instead of sigaction |
| * propagate syntax errors, die on resource errors? |
| * continuation lines, both explicit and implicit - done? |
| * memory leak finding and plugging - done? |
| * more testing, especially quoting rules and redirection |
| * document how quoting rules not precisely followed for variable assignments |
| * maybe change charmap[] to use 2-bit entries |
| * (eventually) remove all the printf's |
| * |
| * Licensed under the GPL v2 or later, see the file LICENSE in this tarball. |
| */ |
| |
| |
| #include <glob.h> /* glob, of course */ |
| #include <getopt.h> /* should be pretty obvious */ |
| /* #include <dmalloc.h> */ |
| |
| #include "busybox.h" /* for APPLET_IS_NOFORK/NOEXEC */ |
| |
| |
| #if !BB_MMU && ENABLE_HUSH_TICK |
| //#undef ENABLE_HUSH_TICK |
| //#define ENABLE_HUSH_TICK 0 |
| #warning On NOMMU, hush command substitution is dangerous. |
| #warning Dont use it for commands which produce lots of output. |
| #warning For more info see shell/hush.c, generate_stream_from_list(). |
| #endif |
| |
| #if !BB_MMU && ENABLE_HUSH_JOB |
| #undef ENABLE_HUSH_JOB |
| #define ENABLE_HUSH_JOB 0 |
| #endif |
| |
| #if !ENABLE_HUSH_INTERACTIVE |
| #undef ENABLE_FEATURE_EDITING |
| #define ENABLE_FEATURE_EDITING 0 |
| #undef ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| #define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0 |
| #endif |
| |
| |
| /* If you comment out one of these below, it will be #defined later |
| * to perform debug printfs to stderr: */ |
| #define debug_printf(...) do {} while (0) |
| /* Finer-grained debug switches */ |
| #define debug_printf_parse(...) do {} while (0) |
| #define debug_print_tree(a, b) do {} while (0) |
| #define debug_printf_exec(...) do {} while (0) |
| #define debug_printf_jobs(...) do {} while (0) |
| #define debug_printf_expand(...) do {} while (0) |
| #define debug_printf_clean(...) do {} while (0) |
| |
| #ifndef debug_printf |
| #define debug_printf(...) fprintf(stderr, __VA_ARGS__) |
| #endif |
| |
| #ifndef debug_printf_parse |
| #define debug_printf_parse(...) fprintf(stderr, __VA_ARGS__) |
| #endif |
| |
| #ifndef debug_printf_exec |
| #define debug_printf_exec(...) fprintf(stderr, __VA_ARGS__) |
| #endif |
| |
| #ifndef debug_printf_jobs |
| #define debug_printf_jobs(...) fprintf(stderr, __VA_ARGS__) |
| #define DEBUG_SHELL_JOBS 1 |
| #endif |
| |
| #ifndef debug_printf_expand |
| #define debug_printf_expand(...) fprintf(stderr, __VA_ARGS__) |
| #define DEBUG_EXPAND 1 |
| #endif |
| |
| /* Keep unconditionally on for now */ |
| #define ENABLE_HUSH_DEBUG 1 |
| |
| #ifndef debug_printf_clean |
| /* broken, of course, but OK for testing */ |
| static const char *indenter(int i) |
| { |
| static const char blanks[] ALIGN1 = |
| " "; |
| return &blanks[sizeof(blanks) - i - 1]; |
| } |
| #define debug_printf_clean(...) fprintf(stderr, __VA_ARGS__) |
| #define DEBUG_CLEAN 1 |
| #endif |
| |
| |
| /* |
| * Leak hunting. Use hush_leaktool.sh for post-processing. |
| */ |
| #ifdef FOR_HUSH_LEAKTOOL |
| void *xxmalloc(int lineno, size_t size) |
| { |
| void *ptr = xmalloc((size + 0xff) & ~0xff); |
| fprintf(stderr, "line %d: malloc %p\n", lineno, ptr); |
| return ptr; |
| } |
| void *xxrealloc(int lineno, void *ptr, size_t size) |
| { |
| ptr = xrealloc(ptr, (size + 0xff) & ~0xff); |
| fprintf(stderr, "line %d: realloc %p\n", lineno, ptr); |
| return ptr; |
| } |
| char *xxstrdup(int lineno, const char *str) |
| { |
| char *ptr = xstrdup(str); |
| fprintf(stderr, "line %d: strdup %p\n", lineno, ptr); |
| return ptr; |
| } |
| void xxfree(void *ptr) |
| { |
| fprintf(stderr, "free %p\n", ptr); |
| free(ptr); |
| } |
| #define xmalloc(s) xxmalloc(__LINE__, s) |
| #define xrealloc(p, s) xxrealloc(__LINE__, p, s) |
| #define xstrdup(s) xxstrdup(__LINE__, s) |
| #define free(p) xxfree(p) |
| #endif |
| |
| |
| #define SPECIAL_VAR_SYMBOL 3 |
| |
| #define PARSEFLAG_EXIT_FROM_LOOP 1 |
| #define PARSEFLAG_SEMICOLON (1 << 1) /* symbol ';' is special for parser */ |
| #define PARSEFLAG_REPARSING (1 << 2) /* >= 2nd pass */ |
| |
| typedef enum { |
| REDIRECT_INPUT = 1, |
| REDIRECT_OVERWRITE = 2, |
| REDIRECT_APPEND = 3, |
| REDIRECT_HEREIS = 4, |
| REDIRECT_IO = 5 |
| } redir_type; |
| |
| /* The descrip member of this structure is only used to make debugging |
| * output pretty */ |
| static const struct { |
| int mode; |
| signed char default_fd; |
| char descrip[3]; |
| } redir_table[] = { |
| { 0, 0, "()" }, |
| { O_RDONLY, 0, "<" }, |
| { O_CREAT|O_TRUNC|O_WRONLY, 1, ">" }, |
| { O_CREAT|O_APPEND|O_WRONLY, 1, ">>" }, |
| { O_RDONLY, -1, "<<" }, |
| { O_RDWR, 1, "<>" } |
| }; |
| |
| typedef enum { |
| PIPE_SEQ = 1, |
| PIPE_AND = 2, |
| PIPE_OR = 3, |
| PIPE_BG = 4, |
| } pipe_style; |
| |
| /* might eventually control execution */ |
| typedef enum { |
| RES_NONE = 0, |
| #if ENABLE_HUSH_IF |
| RES_IF = 1, |
| RES_THEN = 2, |
| RES_ELIF = 3, |
| RES_ELSE = 4, |
| RES_FI = 5, |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| RES_FOR = 6, |
| RES_WHILE = 7, |
| RES_UNTIL = 8, |
| RES_DO = 9, |
| RES_DONE = 10, |
| RES_IN = 11, |
| #endif |
| RES_XXXX = 12, |
| RES_SNTX = 13 |
| } reserved_style; |
| enum { |
| FLAG_END = (1 << RES_NONE ), |
| #if ENABLE_HUSH_IF |
| FLAG_IF = (1 << RES_IF ), |
| FLAG_THEN = (1 << RES_THEN ), |
| FLAG_ELIF = (1 << RES_ELIF ), |
| FLAG_ELSE = (1 << RES_ELSE ), |
| FLAG_FI = (1 << RES_FI ), |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| FLAG_FOR = (1 << RES_FOR ), |
| FLAG_WHILE = (1 << RES_WHILE), |
| FLAG_UNTIL = (1 << RES_UNTIL), |
| FLAG_DO = (1 << RES_DO ), |
| FLAG_DONE = (1 << RES_DONE ), |
| FLAG_IN = (1 << RES_IN ), |
| #endif |
| FLAG_START = (1 << RES_XXXX ), |
| }; |
| |
| /* This holds pointers to the various results of parsing */ |
| struct p_context { |
| struct child_prog *child; |
| struct pipe *list_head; |
| struct pipe *pipe; |
| struct redir_struct *pending_redirect; |
| smallint res_w; |
| smallint parse_type; /* bitmask of PARSEFLAG_xxx, defines type of parser : ";$" common or special symbol */ |
| int old_flag; /* bitmask of FLAG_xxx, for figuring out valid reserved words */ |
| struct p_context *stack; |
| /* How about quoting status? */ |
| }; |
| |
| struct redir_struct { |
| struct redir_struct *next; /* pointer to the next redirect in the list */ |
| redir_type type; /* type of redirection */ |
| int fd; /* file descriptor being redirected */ |
| int dup; /* -1, or file descriptor being duplicated */ |
| char **glob_word; /* *word.gl_pathv is the filename */ |
| }; |
| |
| struct child_prog { |
| pid_t pid; /* 0 if exited */ |
| char **argv; /* program name and arguments */ |
| struct pipe *group; /* if non-NULL, first in group or subshell */ |
| smallint subshell; /* flag, non-zero if group must be forked */ |
| smallint is_stopped; /* is the program currently running? */ |
| struct redir_struct *redirects; /* I/O redirections */ |
| struct pipe *family; /* pointer back to the child's parent pipe */ |
| //sp counting seems to be broken... so commented out, grep for '//sp:' |
| //sp: int sp; /* number of SPECIAL_VAR_SYMBOL */ |
| //seems to be unused, grep for '//pt:' |
| //pt: int parse_type; |
| }; |
| /* argv vector may contain variable references (^Cvar^C, ^C0^C etc) |
| * and on execution these are substituted with their values. |
| * Substitution can make _several_ words out of one argv[n]! |
| * Example: argv[0]=='.^C*^C.' here: echo .$*. |
| */ |
| |
| struct pipe { |
| struct pipe *next; |
| int num_progs; /* total number of programs in job */ |
| int running_progs; /* number of programs running (not exited) */ |
| int stopped_progs; /* number of programs alive, but stopped */ |
| #if ENABLE_HUSH_JOB |
| int jobid; /* job number */ |
| pid_t pgrp; /* process group ID for the job */ |
| char *cmdtext; /* name of job */ |
| #endif |
| char *cmdbuf; /* buffer various argv's point into */ |
| struct child_prog *progs; /* array of commands in pipe */ |
| int job_context; /* bitmask defining current context */ |
| smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ |
| smallint res_word; /* needed for if, for, while, until... */ |
| }; |
| |
| /* On program start, environ points to initial environment. |
| * putenv adds new pointers into it, unsetenv removes them. |
| * Neither of these (de)allocates the strings. |
| * setenv allocates new strings in malloc space and does putenv, |
| * and thus setenv is unusable (leaky) for shell's purposes */ |
| #define setenv(...) setenv_is_leaky_dont_use() |
| struct variable { |
| struct variable *next; |
| char *varstr; /* points to "name=" portion */ |
| int max_len; /* if > 0, name is part of initial env; else name is malloced */ |
| smallint flg_export; /* putenv should be done on this var */ |
| smallint flg_read_only; |
| }; |
| |
| typedef struct { |
| char *data; |
| int length; |
| int maxlen; |
| smallint o_quote; |
| smallint nonnull; |
| } o_string; |
| #define NULL_O_STRING {NULL,0,0,0,0} |
| /* used for initialization: o_string foo = NULL_O_STRING; */ |
| |
| /* I can almost use ordinary FILE *. Is open_memstream() universally |
| * available? Where is it documented? */ |
| struct in_str { |
| const char *p; |
| /* eof_flag=1: last char in ->p is really an EOF */ |
| char eof_flag; /* meaningless if ->p == NULL */ |
| char peek_buf[2]; |
| #if ENABLE_HUSH_INTERACTIVE |
| smallint promptme; |
| smallint promptmode; /* 0: PS1, 1: PS2 */ |
| #endif |
| FILE *file; |
| int (*get) (struct in_str *); |
| int (*peek) (struct in_str *); |
| }; |
| #define b_getch(input) ((input)->get(input)) |
| #define b_peek(input) ((input)->peek(input)) |
| |
| enum { |
| CHAR_ORDINARY = 0, |
| CHAR_ORDINARY_IF_QUOTED = 1, /* example: *, # */ |
| CHAR_IFS = 2, /* treated as ordinary if quoted */ |
| CHAR_SPECIAL = 3, /* example: $ */ |
| }; |
| |
| #define HUSH_VER_STR "0.02" |
| |
| /* "Globals" within this file */ |
| |
| /* Sorted roughly by size (smaller offsets == smaller code) */ |
| struct globals { |
| #if ENABLE_HUSH_INTERACTIVE |
| /* 'interactive_fd' is a fd# open to ctty, if we have one |
| * _AND_ if we decided to act interactively */ |
| int interactive_fd; |
| const char *PS1; |
| const char *PS2; |
| #endif |
| #if ENABLE_FEATURE_EDITING |
| line_input_t *line_input_state; |
| #endif |
| #if ENABLE_HUSH_JOB |
| int run_list_level; |
| pid_t saved_task_pgrp; |
| pid_t saved_tty_pgrp; |
| int last_jobid; |
| struct pipe *job_list; |
| struct pipe *toplevel_list; |
| smallint ctrl_z_flag; |
| #endif |
| smallint fake_mode; |
| /* these three support $?, $#, and $1 */ |
| char **global_argv; |
| int global_argc; |
| int last_return_code; |
| const char *ifs; |
| const char *cwd; |
| unsigned last_bg_pid; |
| struct variable *top_var; /* = &shell_ver (set in main()) */ |
| struct variable shell_ver; |
| #if ENABLE_FEATURE_SH_STANDALONE |
| struct nofork_save_area nofork_save; |
| #endif |
| #if ENABLE_HUSH_JOB |
| sigjmp_buf toplevel_jb; |
| #endif |
| unsigned char charmap[256]; |
| char user_input_buf[ENABLE_FEATURE_EDITING ? BUFSIZ : 2]; |
| }; |
| |
| #define G (*ptr_to_globals) |
| |
| #if !ENABLE_HUSH_INTERACTIVE |
| enum { interactive_fd = 0 }; |
| #endif |
| #if !ENABLE_HUSH_JOB |
| enum { run_list_level = 0 }; |
| #endif |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| #define interactive_fd (G.interactive_fd ) |
| #define PS1 (G.PS1 ) |
| #define PS2 (G.PS2 ) |
| #endif |
| #if ENABLE_FEATURE_EDITING |
| #define line_input_state (G.line_input_state) |
| #endif |
| #if ENABLE_HUSH_JOB |
| #define run_list_level (G.run_list_level ) |
| #define saved_task_pgrp (G.saved_task_pgrp ) |
| #define saved_tty_pgrp (G.saved_tty_pgrp ) |
| #define last_jobid (G.last_jobid ) |
| #define job_list (G.job_list ) |
| #define toplevel_list (G.toplevel_list ) |
| #define toplevel_jb (G.toplevel_jb ) |
| #define ctrl_z_flag (G.ctrl_z_flag ) |
| #endif /* JOB */ |
| #define global_argv (G.global_argv ) |
| #define global_argc (G.global_argc ) |
| #define last_return_code (G.last_return_code) |
| #define ifs (G.ifs ) |
| #define fake_mode (G.fake_mode ) |
| #define cwd (G.cwd ) |
| #define last_bg_pid (G.last_bg_pid ) |
| #define top_var (G.top_var ) |
| #define shell_ver (G.shell_ver ) |
| #if ENABLE_FEATURE_SH_STANDALONE |
| #define nofork_save (G.nofork_save ) |
| #endif |
| #if ENABLE_HUSH_JOB |
| #define toplevel_jb (G.toplevel_jb ) |
| #endif |
| #define charmap (G.charmap ) |
| #define user_input_buf (G.user_input_buf ) |
| #define INIT_G() do { \ |
| SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \ |
| } while (0) |
| |
| |
| #define B_CHUNK 100 |
| #define B_NOSPAC 1 |
| #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" |
| |
| #if 1 |
| /* Normal */ |
| static void syntax(const char *msg) |
| { |
| /* Was using fancy stuff: |
| * (interactive_fd ? bb_error_msg : bb_error_msg_and_die)(...params...) |
| * but it SEGVs. ?! Oh well... explicit temp ptr works around that */ |
| void (*fp)(const char *s, ...); |
| |
| fp = (interactive_fd ? bb_error_msg : bb_error_msg_and_die); |
| fp(msg ? "%s: %s" : "syntax error", "syntax error", msg); |
| } |
| |
| #else |
| /* Debug */ |
| static void syntax_lineno(int line) |
| { |
| void (*fp)(const char *s, ...); |
| |
| fp = (interactive_fd ? bb_error_msg : bb_error_msg_and_die); |
| fp("syntax error hush.c:%d", line); |
| } |
| #define syntax(str) syntax_lineno(__LINE__) |
| #endif |
| |
| /* Index of subroutines: */ |
| /* o_string manipulation: */ |
| static int b_check_space(o_string *o, int len); |
| static int b_addchr(o_string *o, int ch); |
| static void b_reset(o_string *o); |
| static int b_addqchr(o_string *o, int ch, int quote); |
| /* in_str manipulations: */ |
| static int static_get(struct in_str *i); |
| static int static_peek(struct in_str *i); |
| static int file_get(struct in_str *i); |
| static int file_peek(struct in_str *i); |
| static void setup_file_in_str(struct in_str *i, FILE *f); |
| static void setup_string_in_str(struct in_str *i, const char *s); |
| /* "run" the final data structures: */ |
| #if !defined(DEBUG_CLEAN) |
| #define free_pipe_list(head, indent) free_pipe_list(head) |
| #define free_pipe(pi, indent) free_pipe(pi) |
| #endif |
| static int free_pipe_list(struct pipe *head, int indent); |
| static int free_pipe(struct pipe *pi, int indent); |
| /* really run the final data structures: */ |
| static int setup_redirects(struct child_prog *prog, int squirrel[]); |
| static int run_list(struct pipe *pi); |
| static void pseudo_exec_argv(char **argv) ATTRIBUTE_NORETURN; |
| static void pseudo_exec(struct child_prog *child) ATTRIBUTE_NORETURN; |
| static int run_pipe(struct pipe *pi); |
| /* extended glob support: */ |
| static char **globhack(const char *src, char **strings); |
| static int glob_needed(const char *s); |
| static int xglob(o_string *dest, char ***pglob); |
| /* variable assignment: */ |
| static int is_assignment(const char *s); |
| /* data structure manipulation: */ |
| static int setup_redirect(struct p_context *ctx, int fd, redir_type style, struct in_str *input); |
| static void initialize_context(struct p_context *ctx); |
| static int done_word(o_string *dest, struct p_context *ctx); |
| static int done_command(struct p_context *ctx); |
| static int done_pipe(struct p_context *ctx, pipe_style type); |
| /* primary string parsing: */ |
| static int redirect_dup_num(struct in_str *input); |
| static int redirect_opt_num(o_string *o); |
| #if ENABLE_HUSH_TICK |
| static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, const char *subst_end); |
| #endif |
| static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch); |
| static const char *lookup_param(const char *src); |
| static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input); |
| static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, const char *end_trigger); |
| /* setup: */ |
| static int parse_and_run_stream(struct in_str *inp, int parse_flag); |
| static int parse_and_run_string(const char *s, int parse_flag); |
| static int parse_and_run_file(FILE *f); |
| /* job management: */ |
| static int checkjobs(struct pipe* fg_pipe); |
| #if ENABLE_HUSH_JOB |
| static int checkjobs_and_fg_shell(struct pipe* fg_pipe); |
| static void insert_bg_job(struct pipe *pi); |
| static void remove_bg_job(struct pipe *pi); |
| static void delete_finished_bg_job(struct pipe *pi); |
| #else |
| int checkjobs_and_fg_shell(struct pipe* fg_pipe); /* never called */ |
| #endif |
| /* local variable support */ |
| static char **expand_strvec_to_strvec(char **argv); |
| /* used for eval */ |
| static char *expand_strvec_to_string(char **argv); |
| /* used for expansion of right hand of assignments */ |
| static char *expand_string_to_string(const char *str); |
| static struct variable *get_local_var(const char *name); |
| static int set_local_var(char *str, int flg_export); |
| static void unset_local_var(const char *name); |
| |
| |
| static char **add_strings_to_strings(int need_xstrdup, char **strings, char **add) |
| { |
| int i; |
| unsigned count1; |
| unsigned count2; |
| char **v; |
| |
| v = strings; |
| count1 = 0; |
| if (v) { |
| while (*v) { |
| count1++; |
| v++; |
| } |
| } |
| count2 = 0; |
| v = add; |
| while (*v) { |
| count2++; |
| v++; |
| } |
| v = xrealloc(strings, (count1 + count2 + 1) * sizeof(char*)); |
| v[count1 + count2] = NULL; |
| i = count2; |
| while (--i >= 0) |
| v[count1 + i] = need_xstrdup ? xstrdup(add[i]) : add[i]; |
| return v; |
| } |
| |
| /* 'add' should be a malloced pointer */ |
| static char **add_string_to_strings(char **strings, char *add) |
| { |
| char *v[2]; |
| |
| v[0] = add; |
| v[1] = NULL; |
| |
| return add_strings_to_strings(0, strings, v); |
| } |
| |
| static void free_strings(char **strings) |
| { |
| if (strings) { |
| char **v = strings; |
| while (*v) |
| free(*v++); |
| free(strings); |
| } |
| } |
| |
| |
| /* Function prototypes for builtins */ |
| static int builtin_cd(char **argv); |
| static int builtin_echo(char **argv); |
| static int builtin_eval(char **argv); |
| static int builtin_exec(char **argv); |
| static int builtin_exit(char **argv); |
| static int builtin_export(char **argv); |
| #if ENABLE_HUSH_JOB |
| static int builtin_fg_bg(char **argv); |
| static int builtin_jobs(char **argv); |
| #endif |
| #if ENABLE_HUSH_HELP |
| static int builtin_help(char **argv); |
| #endif |
| static int builtin_pwd(char **argv); |
| static int builtin_read(char **argv); |
| static int builtin_test(char **argv); |
| static int builtin_set(char **argv); |
| static int builtin_shift(char **argv); |
| static int builtin_source(char **argv); |
| static int builtin_umask(char **argv); |
| static int builtin_unset(char **argv); |
| //static int builtin_not_written(char **argv); |
| |
| /* Table of built-in functions. They can be forked or not, depending on |
| * context: within pipes, they fork. As simple commands, they do not. |
| * When used in non-forking context, they can change global variables |
| * in the parent shell process. If forked, of course they cannot. |
| * For example, 'unset foo | whatever' will parse and run, but foo will |
| * still be set at the end. */ |
| struct built_in_command { |
| const char *cmd; /* name */ |
| int (*function) (char **argv); /* function ptr */ |
| #if ENABLE_HUSH_HELP |
| const char *descr; /* description */ |
| #define BLTIN(cmd, func, help) { cmd, func, help } |
| #else |
| #define BLTIN(cmd, func, help) { cmd, func } |
| #endif |
| }; |
| |
| /* For now, echo and test are unconditionally enabled. |
| * Maybe make it configurable? */ |
| static const struct built_in_command bltins[] = { |
| BLTIN("[" , builtin_test, "Test condition"), |
| BLTIN("[[" , builtin_test, "Test condition"), |
| #if ENABLE_HUSH_JOB |
| BLTIN("bg" , builtin_fg_bg, "Resume a job in the background"), |
| #endif |
| // BLTIN("break" , builtin_not_written, "Exit for, while or until loop"), |
| BLTIN("cd" , builtin_cd, "Change working directory"), |
| // BLTIN("continue", builtin_not_written, "Continue for, while or until loop"), |
| BLTIN("echo" , builtin_echo, "Write strings to stdout"), |
| BLTIN("eval" , builtin_eval, "Construct and run shell command"), |
| BLTIN("exec" , builtin_exec, "Exec command, replacing this shell with the exec'd process"), |
| BLTIN("exit" , builtin_exit, "Exit from shell"), |
| BLTIN("export", builtin_export, "Set environment variable"), |
| #if ENABLE_HUSH_JOB |
| BLTIN("fg" , builtin_fg_bg, "Bring job into the foreground"), |
| BLTIN("jobs" , builtin_jobs, "Lists the active jobs"), |
| #endif |
| // TODO: remove pwd? we have it as an applet... |
| BLTIN("pwd" , builtin_pwd, "Print current directory"), |
| BLTIN("read" , builtin_read, "Input environment variable"), |
| // BLTIN("return", builtin_not_written, "Return from a function"), |
| BLTIN("set" , builtin_set, "Set/unset shell local variables"), |
| BLTIN("shift" , builtin_shift, "Shift positional parameters"), |
| // BLTIN("trap" , builtin_not_written, "Trap signals"), |
| BLTIN("test" , builtin_test, "Test condition"), |
| // BLTIN("ulimit", builtin_not_written, "Controls resource limits"), |
| BLTIN("umask" , builtin_umask, "Sets file creation mask"), |
| BLTIN("unset" , builtin_unset, "Unset environment variable"), |
| BLTIN("." , builtin_source, "Source-in and run commands in a file"), |
| #if ENABLE_HUSH_HELP |
| BLTIN("help" , builtin_help, "List shell built-in commands"), |
| #endif |
| BLTIN(NULL, NULL, NULL) |
| }; |
| |
| #if ENABLE_HUSH_JOB |
| |
| /* Signals are grouped, we handle them in batches */ |
| static void set_fatal_sighandler(void (*handler)(int)) |
| { |
| bb_signals(0 |
| + (1 << SIGILL) |
| + (1 << SIGTRAP) |
| + (1 << SIGABRT) |
| + (1 << SIGFPE) |
| + (1 << SIGBUS) |
| + (1 << SIGSEGV) |
| /* bash 3.2 seems to handle these just like 'fatal' ones */ |
| + (1 << SIGHUP) |
| + (1 << SIGPIPE) |
| + (1 << SIGALRM) |
| , handler); |
| } |
| static void set_jobctrl_sighandler(void (*handler)(int)) |
| { |
| bb_signals(0 |
| + (1 << SIGTSTP) |
| + (1 << SIGTTIN) |
| + (1 << SIGTTOU) |
| , handler); |
| } |
| static void set_misc_sighandler(void (*handler)(int)) |
| { |
| bb_signals(0 |
| + (1 << SIGINT) |
| + (1 << SIGQUIT) |
| + (1 << SIGTERM) |
| , handler); |
| } |
| /* SIGCHLD is special and handled separately */ |
| |
| static void set_every_sighandler(void (*handler)(int)) |
| { |
| set_fatal_sighandler(handler); |
| set_jobctrl_sighandler(handler); |
| set_misc_sighandler(handler); |
| signal(SIGCHLD, handler); |
| } |
| |
| static void handler_ctrl_c(int sig) |
| { |
| debug_printf_jobs("got sig %d\n", sig); |
| // as usual we can have all kinds of nasty problems with leaked malloc data here |
| siglongjmp(toplevel_jb, 1); |
| } |
| |
| static void handler_ctrl_z(int sig) |
| { |
| pid_t pid; |
| |
| debug_printf_jobs("got tty sig %d in pid %d\n", sig, getpid()); |
| pid = fork(); |
| if (pid < 0) /* can't fork. Pretend there was no ctrl-Z */ |
| return; |
| ctrl_z_flag = 1; |
| if (!pid) { /* child */ |
| if (ENABLE_HUSH_JOB) |
| die_sleep = 0; /* let nofork's xfuncs die */ |
| setpgrp(); |
| debug_printf_jobs("set pgrp for child %d ok\n", getpid()); |
| set_every_sighandler(SIG_DFL); |
| raise(SIGTSTP); /* resend TSTP so that child will be stopped */ |
| debug_printf_jobs("returning in child\n"); |
| /* return to nofork, it will eventually exit now, |
| * not return back to shell */ |
| return; |
| } |
| /* parent */ |
| /* finish filling up pipe info */ |
| toplevel_list->pgrp = pid; /* child is in its own pgrp */ |
| toplevel_list->progs[0].pid = pid; |
| /* parent needs to longjmp out of running nofork. |
| * we will "return" exitcode 0, with child put in background */ |
| // as usual we can have all kinds of nasty problems with leaked malloc data here |
| debug_printf_jobs("siglongjmp in parent\n"); |
| siglongjmp(toplevel_jb, 1); |
| } |
| |
| /* Restores tty foreground process group, and exits. |
| * May be called as signal handler for fatal signal |
| * (will faithfully resend signal to itself, producing correct exit state) |
| * or called directly with -EXITCODE. |
| * We also call it if xfunc is exiting. */ |
| static void sigexit(int sig) ATTRIBUTE_NORETURN; |
| static void sigexit(int sig) |
| { |
| /* Disable all signals: job control, SIGPIPE, etc. */ |
| sigprocmask_allsigs(SIG_BLOCK); |
| |
| if (interactive_fd) |
| tcsetpgrp(interactive_fd, saved_tty_pgrp); |
| |
| /* Not a signal, just exit */ |
| if (sig <= 0) |
| _exit(- sig); |
| |
| kill_myself_with_sig(sig); /* does not return */ |
| } |
| |
| /* Restores tty foreground process group, and exits. */ |
| static void hush_exit(int exitcode) ATTRIBUTE_NORETURN; |
| static void hush_exit(int exitcode) |
| { |
| fflush(NULL); /* flush all streams */ |
| sigexit(- (exitcode & 0xff)); |
| } |
| |
| #else /* !JOB */ |
| |
| #define set_fatal_sighandler(handler) ((void)0) |
| #define set_jobctrl_sighandler(handler) ((void)0) |
| #define set_misc_sighandler(handler) ((void)0) |
| #define hush_exit(e) exit(e) |
| |
| #endif /* JOB */ |
| |
| |
| static const char *set_cwd(void) |
| { |
| if (cwd == bb_msg_unknown) |
| cwd = NULL; /* xrealloc_getcwd_or_warn(arg) calls free(arg)! */ |
| cwd = xrealloc_getcwd_or_warn((char *)cwd); |
| if (!cwd) |
| cwd = bb_msg_unknown; |
| return cwd; |
| } |
| |
| |
| /* built-in 'test' handler */ |
| static int builtin_test(char **argv) |
| { |
| int argc = 0; |
| while (*argv) { |
| argc++; |
| argv++; |
| } |
| return test_main(argc, argv - argc); |
| } |
| |
| /* built-in 'test' handler */ |
| static int builtin_echo(char **argv) |
| { |
| int argc = 0; |
| while (*argv) { |
| argc++; |
| argv++; |
| } |
| return echo_main(argc, argv - argc); |
| } |
| |
| /* built-in 'eval' handler */ |
| static int builtin_eval(char **argv) |
| { |
| int rcode = EXIT_SUCCESS; |
| |
| if (argv[1]) { |
| char *str = expand_strvec_to_string(argv + 1); |
| parse_and_run_string(str, PARSEFLAG_EXIT_FROM_LOOP | |
| PARSEFLAG_SEMICOLON); |
| free(str); |
| rcode = last_return_code; |
| } |
| return rcode; |
| } |
| |
| /* built-in 'cd <path>' handler */ |
| static int builtin_cd(char **argv) |
| { |
| const char *newdir; |
| if (argv[1] == NULL) { |
| // bash does nothing (exitcode 0) if HOME is ""; if it's unset, |
| // bash says "bash: cd: HOME not set" and does nothing (exitcode 1) |
| newdir = getenv("HOME") ? : "/"; |
| } else |
| newdir = argv[1]; |
| if (chdir(newdir)) { |
| printf("cd: %s: %s\n", newdir, strerror(errno)); |
| return EXIT_FAILURE; |
| } |
| set_cwd(); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'exec' handler */ |
| static int builtin_exec(char **argv) |
| { |
| if (argv[1] == NULL) |
| return EXIT_SUCCESS; /* Really? */ |
| pseudo_exec_argv(argv + 1); |
| /* never returns */ |
| } |
| |
| /* built-in 'exit' handler */ |
| static int builtin_exit(char **argv) |
| { |
| // TODO: bash does it ONLY on top-level sh exit (+interacive only?) |
| //puts("exit"); /* bash does it */ |
| // TODO: warn if we have background jobs: "There are stopped jobs" |
| // On second consecutive 'exit', exit anyway. |
| |
| if (argv[1] == NULL) |
| hush_exit(last_return_code); |
| /* mimic bash: exit 123abc == exit 255 + error msg */ |
| xfunc_error_retval = 255; |
| /* bash: exit -2 == exit 254, no error msg */ |
| hush_exit(xatoi(argv[1]) & 0xff); |
| } |
| |
| /* built-in 'export VAR=value' handler */ |
| static int builtin_export(char **argv) |
| { |
| const char *value; |
| char *name = argv[1]; |
| |
| if (name == NULL) { |
| // TODO: |
| // ash emits: export VAR='VAL' |
| // bash: declare -x VAR="VAL" |
| // (both also escape as needed (quotes, $, etc)) |
| char **e = environ; |
| if (e) |
| while (*e) |
| puts(*e++); |
| return EXIT_SUCCESS; |
| } |
| |
| value = strchr(name, '='); |
| if (!value) { |
| /* They are exporting something without a =VALUE */ |
| struct variable *var; |
| |
| var = get_local_var(name); |
| if (var) { |
| var->flg_export = 1; |
| putenv(var->varstr); |
| } |
| /* bash does not return an error when trying to export |
| * an undefined variable. Do likewise. */ |
| return EXIT_SUCCESS; |
| } |
| |
| set_local_var(xstrdup(name), 1); |
| return EXIT_SUCCESS; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* built-in 'fg' and 'bg' handler */ |
| static int builtin_fg_bg(char **argv) |
| { |
| int i, jobnum; |
| struct pipe *pi; |
| |
| if (!interactive_fd) |
| return EXIT_FAILURE; |
| /* If they gave us no args, assume they want the last backgrounded task */ |
| if (!argv[1]) { |
| for (pi = job_list; pi; pi = pi->next) { |
| if (pi->jobid == last_jobid) { |
| goto found; |
| } |
| } |
| bb_error_msg("%s: no current job", argv[0]); |
| return EXIT_FAILURE; |
| } |
| if (sscanf(argv[1], "%%%d", &jobnum) != 1) { |
| bb_error_msg("%s: bad argument '%s'", argv[0], argv[1]); |
| return EXIT_FAILURE; |
| } |
| for (pi = job_list; pi; pi = pi->next) { |
| if (pi->jobid == jobnum) { |
| goto found; |
| } |
| } |
| bb_error_msg("%s: %d: no such job", argv[0], jobnum); |
| return EXIT_FAILURE; |
| found: |
| // TODO: bash prints a string representation |
| // of job being foregrounded (like "sleep 1 | cat") |
| if (*argv[0] == 'f') { |
| /* Put the job into the foreground. */ |
| tcsetpgrp(interactive_fd, pi->pgrp); |
| } |
| |
| /* Restart the processes in the job */ |
| debug_printf_jobs("reviving %d procs, pgrp %d\n", pi->num_progs, pi->pgrp); |
| for (i = 0; i < pi->num_progs; i++) { |
| debug_printf_jobs("reviving pid %d\n", pi->progs[i].pid); |
| pi->progs[i].is_stopped = 0; |
| } |
| pi->stopped_progs = 0; |
| |
| i = kill(- pi->pgrp, SIGCONT); |
| if (i < 0) { |
| if (errno == ESRCH) { |
| delete_finished_bg_job(pi); |
| return EXIT_SUCCESS; |
| } else { |
| bb_perror_msg("kill (SIGCONT)"); |
| } |
| } |
| |
| if (*argv[0] == 'f') { |
| remove_bg_job(pi); |
| return checkjobs_and_fg_shell(pi); |
| } |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| /* built-in 'help' handler */ |
| #if ENABLE_HUSH_HELP |
| static int builtin_help(char **argv ATTRIBUTE_UNUSED) |
| { |
| const struct built_in_command *x; |
| |
| printf("\nBuilt-in commands:\n"); |
| printf("-------------------\n"); |
| for (x = bltins; x->cmd; x++) { |
| printf("%s\t%s\n", x->cmd, x->descr); |
| } |
| printf("\n\n"); |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| #if ENABLE_HUSH_JOB |
| /* built-in 'jobs' handler */ |
| static int builtin_jobs(char **argv ATTRIBUTE_UNUSED) |
| { |
| struct pipe *job; |
| const char *status_string; |
| |
| for (job = job_list; job; job = job->next) { |
| if (job->running_progs == job->stopped_progs) |
| status_string = "Stopped"; |
| else |
| status_string = "Running"; |
| |
| printf(JOB_STATUS_FORMAT, job->jobid, status_string, job->cmdtext); |
| } |
| return EXIT_SUCCESS; |
| } |
| #endif |
| |
| /* built-in 'pwd' handler */ |
| static int builtin_pwd(char **argv ATTRIBUTE_UNUSED) |
| { |
| puts(set_cwd()); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'read VAR' handler */ |
| static int builtin_read(char **argv) |
| { |
| char *string; |
| const char *name = argv[1] ? argv[1] : "REPLY"; |
| |
| string = xmalloc_reads(STDIN_FILENO, xasprintf("%s=", name)); |
| return set_local_var(string, 0); |
| } |
| |
| /* built-in 'set [VAR=value]' handler */ |
| static int builtin_set(char **argv) |
| { |
| char *temp = argv[1]; |
| struct variable *e; |
| |
| if (temp == NULL) |
| for (e = top_var; e; e = e->next) |
| puts(e->varstr); |
| else |
| set_local_var(xstrdup(temp), 0); |
| |
| return EXIT_SUCCESS; |
| } |
| |
| |
| /* Built-in 'shift' handler */ |
| static int builtin_shift(char **argv) |
| { |
| int n = 1; |
| if (argv[1]) { |
| n = atoi(argv[1]); |
| } |
| if (n >= 0 && n < global_argc) { |
| global_argv[n] = global_argv[0]; |
| global_argc -= n; |
| global_argv += n; |
| return EXIT_SUCCESS; |
| } |
| return EXIT_FAILURE; |
| } |
| |
| /* Built-in '.' handler (read-in and execute commands from file) */ |
| static int builtin_source(char **argv) |
| { |
| FILE *input; |
| int status; |
| |
| if (argv[1] == NULL) |
| return EXIT_FAILURE; |
| |
| /* XXX search through $PATH is missing */ |
| input = fopen(argv[1], "r"); |
| if (!input) { |
| bb_error_msg("cannot open '%s'", argv[1]); |
| return EXIT_FAILURE; |
| } |
| close_on_exec_on(fileno(input)); |
| |
| /* Now run the file */ |
| /* XXX argv and argc are broken; need to save old global_argv |
| * (pointer only is OK!) on this stack frame, |
| * set global_argv=argv+1, recurse, and restore. */ |
| status = parse_and_run_file(input); |
| fclose(input); |
| return status; |
| } |
| |
| static int builtin_umask(char **argv) |
| { |
| mode_t new_umask; |
| const char *arg = argv[1]; |
| char *end; |
| if (arg) { |
| new_umask = strtoul(arg, &end, 8); |
| if (*end != '\0' || end == arg) { |
| return EXIT_FAILURE; |
| } |
| } else { |
| new_umask = umask(0); |
| printf("%.3o\n", (unsigned) new_umask); |
| } |
| umask(new_umask); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'unset VAR' handler */ |
| static int builtin_unset(char **argv) |
| { |
| /* bash always returns true */ |
| unset_local_var(argv[1]); |
| return EXIT_SUCCESS; |
| } |
| |
| //static int builtin_not_written(char **argv) |
| //{ |
| // printf("builtin_%s not written\n", argv[0]); |
| // return EXIT_FAILURE; |
| //} |
| |
| static int b_check_space(o_string *o, int len) |
| { |
| /* It would be easy to drop a more restrictive policy |
| * in here, such as setting a maximum string length */ |
| if (o->length + len > o->maxlen) { |
| /* assert(data == NULL || o->maxlen != 0); */ |
| o->maxlen += (2*len > B_CHUNK ? 2*len : B_CHUNK); |
| o->data = xrealloc(o->data, 1 + o->maxlen); |
| } |
| return o->data == NULL; |
| } |
| |
| static int b_addchr(o_string *o, int ch) |
| { |
| debug_printf("b_addchr: '%c' o->length=%d o=%p\n", ch, o->length, o); |
| if (b_check_space(o, 1)) |
| return B_NOSPAC; |
| o->data[o->length] = ch; |
| o->length++; |
| o->data[o->length] = '\0'; |
| return 0; |
| } |
| |
| static void b_reset(o_string *o) |
| { |
| o->length = 0; |
| o->nonnull = 0; |
| if (o->data) |
| o->data[0] = '\0'; |
| } |
| |
| static void b_free(o_string *o) |
| { |
| free(o->data); |
| memset(o, 0, sizeof(*o)); |
| } |
| |
| /* My analysis of quoting semantics tells me that state information |
| * is associated with a destination, not a source. |
| */ |
| static int b_addqchr(o_string *o, int ch, int quote) |
| { |
| if (quote && strchr("*?[\\", ch)) { |
| int rc; |
| rc = b_addchr(o, '\\'); |
| if (rc) |
| return rc; |
| } |
| return b_addchr(o, ch); |
| } |
| |
| static int static_get(struct in_str *i) |
| { |
| int ch = *i->p++; |
| if (ch == '\0') return EOF; |
| return ch; |
| } |
| |
| static int static_peek(struct in_str *i) |
| { |
| return *i->p; |
| } |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| #if ENABLE_FEATURE_EDITING |
| static void cmdedit_set_initial_prompt(void) |
| { |
| #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| PS1 = NULL; |
| #else |
| PS1 = getenv("PS1"); |
| if (PS1 == NULL) |
| PS1 = "\\w \\$ "; |
| #endif |
| } |
| #endif /* EDITING */ |
| |
| static const char* setup_prompt_string(int promptmode) |
| { |
| const char *prompt_str; |
| debug_printf("setup_prompt_string %d ", promptmode); |
| #if !ENABLE_FEATURE_EDITING_FANCY_PROMPT |
| /* Set up the prompt */ |
| if (promptmode == 0) { /* PS1 */ |
| free((char*)PS1); |
| PS1 = xasprintf("%s %c ", cwd, (geteuid() != 0) ? '$' : '#'); |
| prompt_str = PS1; |
| } else { |
| prompt_str = PS2; |
| } |
| #else |
| prompt_str = (promptmode == 0) ? PS1 : PS2; |
| #endif |
| debug_printf("result '%s'\n", prompt_str); |
| return prompt_str; |
| } |
| |
| static void get_user_input(struct in_str *i) |
| { |
| int r; |
| const char *prompt_str; |
| |
| prompt_str = setup_prompt_string(i->promptmode); |
| #if ENABLE_FEATURE_EDITING |
| /* Enable command line editing only while a command line |
| * is actually being read */ |
| do { |
| r = read_line_input(prompt_str, user_input_buf, BUFSIZ-1, line_input_state); |
| } while (r == 0); /* repeat if Ctrl-C */ |
| i->eof_flag = (r < 0); |
| if (i->eof_flag) { /* EOF/error detected */ |
| user_input_buf[0] = EOF; /* yes, it will be truncated, it's ok */ |
| user_input_buf[1] = '\0'; |
| } |
| #else |
| fputs(prompt_str, stdout); |
| fflush(stdout); |
| user_input_buf[0] = r = fgetc(i->file); |
| /*user_input_buf[1] = '\0'; - already is and never changed */ |
| i->eof_flag = (r == EOF); |
| #endif |
| i->p = user_input_buf; |
| } |
| #endif /* INTERACTIVE */ |
| |
| /* This is the magic location that prints prompts |
| * and gets data back from the user */ |
| static int file_get(struct in_str *i) |
| { |
| int ch; |
| |
| /* If there is data waiting, eat it up */ |
| if (i->p && *i->p) { |
| #if ENABLE_HUSH_INTERACTIVE |
| take_cached: |
| #endif |
| ch = *i->p++; |
| if (i->eof_flag && !*i->p) |
| ch = EOF; |
| } else { |
| /* need to double check i->file because we might be doing something |
| * more complicated by now, like sourcing or substituting. */ |
| #if ENABLE_HUSH_INTERACTIVE |
| if (interactive_fd && i->promptme && i->file == stdin) { |
| do { |
| get_user_input(i); |
| } while (!*i->p); /* need non-empty line */ |
| i->promptmode = 1; /* PS2 */ |
| i->promptme = 0; |
| goto take_cached; |
| } |
| #endif |
| ch = fgetc(i->file); |
| } |
| debug_printf("file_get: got a '%c' %d\n", ch, ch); |
| #if ENABLE_HUSH_INTERACTIVE |
| if (ch == '\n') |
| i->promptme = 1; |
| #endif |
| return ch; |
| } |
| |
| /* All the callers guarantee this routine will never be |
| * used right after a newline, so prompting is not needed. |
| */ |
| static int file_peek(struct in_str *i) |
| { |
| int ch; |
| if (i->p && *i->p) { |
| if (i->eof_flag && !i->p[1]) |
| return EOF; |
| return *i->p; |
| } |
| ch = fgetc(i->file); |
| i->eof_flag = (ch == EOF); |
| i->peek_buf[0] = ch; |
| i->peek_buf[1] = '\0'; |
| i->p = i->peek_buf; |
| debug_printf("file_peek: got a '%c' %d\n", *i->p, *i->p); |
| return ch; |
| } |
| |
| static void setup_file_in_str(struct in_str *i, FILE *f) |
| { |
| i->peek = file_peek; |
| i->get = file_get; |
| #if ENABLE_HUSH_INTERACTIVE |
| i->promptme = 1; |
| i->promptmode = 0; /* PS1 */ |
| #endif |
| i->file = f; |
| i->p = NULL; |
| } |
| |
| static void setup_string_in_str(struct in_str *i, const char *s) |
| { |
| i->peek = static_peek; |
| i->get = static_get; |
| #if ENABLE_HUSH_INTERACTIVE |
| i->promptme = 1; |
| i->promptmode = 0; /* PS1 */ |
| #endif |
| i->p = s; |
| i->eof_flag = 0; |
| } |
| |
| /* squirrel != NULL means we squirrel away copies of stdin, stdout, |
| * and stderr if they are redirected. */ |
| static int setup_redirects(struct child_prog *prog, int squirrel[]) |
| { |
| int openfd, mode; |
| struct redir_struct *redir; |
| |
| for (redir = prog->redirects; redir; redir = redir->next) { |
| if (redir->dup == -1 && redir->glob_word == NULL) { |
| /* something went wrong in the parse. Pretend it didn't happen */ |
| continue; |
| } |
| if (redir->dup == -1) { |
| char *p; |
| mode = redir_table[redir->type].mode; |
| p = expand_string_to_string(redir->glob_word[0]); |
| openfd = open_or_warn(p, mode); |
| free(p); |
| if (openfd < 0) { |
| /* this could get lost if stderr has been redirected, but |
| bash and ash both lose it as well (though zsh doesn't!) */ |
| return 1; |
| } |
| } else { |
| openfd = redir->dup; |
| } |
| |
| if (openfd != redir->fd) { |
| if (squirrel && redir->fd < 3) { |
| squirrel[redir->fd] = dup(redir->fd); |
| } |
| if (openfd == -3) { |
| //close(openfd); // close(-3) ??! |
| } else { |
| dup2(openfd, redir->fd); |
| if (redir->dup == -1) |
| close(openfd); |
| } |
| } |
| } |
| return 0; |
| } |
| |
| static void restore_redirects(int squirrel[]) |
| { |
| int i, fd; |
| for (i = 0; i < 3; i++) { |
| fd = squirrel[i]; |
| if (fd != -1) { |
| /* We simply die on error */ |
| xmove_fd(fd, i); |
| } |
| } |
| } |
| |
| /* Called after [v]fork() in run_pipe(), or from builtin_exec(). |
| * Never returns. |
| * XXX no exit() here. If you don't exec, use _exit instead. |
| * The at_exit handlers apparently confuse the calling process, |
| * in particular stdin handling. Not sure why? -- because of vfork! (vda) */ |
| static void pseudo_exec_argv(char **argv) |
| { |
| int i, rcode; |
| char *p; |
| const struct built_in_command *x; |
| |
| for (i = 0; is_assignment(argv[i]); i++) { |
| debug_printf_exec("pid %d environment modification: %s\n", |
| getpid(), argv[i]); |
| // FIXME: vfork case?? |
| p = expand_string_to_string(argv[i]); |
| putenv(p); |
| } |
| argv += i; |
| /* If a variable is assigned in a forest, and nobody listens, |
| * was it ever really set? |
| */ |
| if (!argv[0]) |
| _exit(EXIT_SUCCESS); |
| |
| argv = expand_strvec_to_strvec(argv); |
| |
| /* |
| * Check if the command matches any of the builtins. |
| * Depending on context, this might be redundant. But it's |
| * easier to waste a few CPU cycles than it is to figure out |
| * if this is one of those cases. |
| */ |
| for (x = bltins; x->cmd; x++) { |
| if (strcmp(argv[0], x->cmd) == 0) { |
| debug_printf_exec("running builtin '%s'\n", argv[0]); |
| rcode = x->function(argv); |
| fflush(stdout); |
| _exit(rcode); |
| } |
| } |
| |
| /* Check if the command matches any busybox applets */ |
| #if ENABLE_FEATURE_SH_STANDALONE |
| if (strchr(argv[0], '/') == NULL) { |
| int a = find_applet_by_name(argv[0]); |
| if (a >= 0) { |
| if (APPLET_IS_NOEXEC(a)) { |
| debug_printf_exec("running applet '%s'\n", argv[0]); |
| // is it ok that run_applet_no_and_exit() does exit(), not _exit()? |
| run_applet_no_and_exit(a, argv); |
| } |
| /* re-exec ourselves with the new arguments */ |
| debug_printf_exec("re-execing applet '%s'\n", argv[0]); |
| execvp(bb_busybox_exec_path, argv); |
| /* If they called chroot or otherwise made the binary no longer |
| * executable, fall through */ |
| } |
| } |
| #endif |
| |
| debug_printf_exec("execing '%s'\n", argv[0]); |
| execvp(argv[0], argv); |
| bb_perror_msg("cannot exec '%s'", argv[0]); |
| _exit(1); |
| } |
| |
| /* Called after [v]fork() in run_pipe() |
| */ |
| static void pseudo_exec(struct child_prog *child) |
| { |
| // FIXME: buggy wrt NOMMU! Must not modify any global data |
| // until it does exec/_exit, but currently it does |
| // (puts malloc'ed stuff into environment) |
| if (child->argv) |
| pseudo_exec_argv(child->argv); |
| |
| if (child->group) { |
| #if !BB_MMU |
| bb_error_msg_and_die("nested lists are not supported on NOMMU"); |
| #else |
| int rcode; |
| |
| #if ENABLE_HUSH_INTERACTIVE |
| // run_list_level now takes care of it? |
| // debug_printf_exec("pseudo_exec: setting interactive_fd=0\n"); |
| // interactive_fd = 0; /* crucial!!!! */ |
| #endif |
| debug_printf_exec("pseudo_exec: run_list\n"); |
| rcode = run_list(child->group); |
| /* OK to leak memory by not calling free_pipe_list, |
| * since this process is about to exit */ |
| _exit(rcode); |
| #endif |
| } |
| |
| /* Can happen. See what bash does with ">foo" by itself. */ |
| debug_printf("trying to pseudo_exec null command\n"); |
| _exit(EXIT_SUCCESS); |
| } |
| |
| #if ENABLE_HUSH_JOB |
| static const char *get_cmdtext(struct pipe *pi) |
| { |
| char **argv; |
| char *p; |
| int len; |
| |
| /* This is subtle. ->cmdtext is created only on first backgrounding. |
| * (Think "cat, <ctrl-z>, fg, <ctrl-z>, fg, <ctrl-z>...." here...) |
| * On subsequent bg argv is trashed, but we won't use it */ |
| if (pi->cmdtext) |
| return pi->cmdtext; |
| argv = pi->progs[0].argv; |
| if (!argv || !argv[0]) |
| return (pi->cmdtext = xzalloc(1)); |
| |
| len = 0; |
| do len += strlen(*argv) + 1; while (*++argv); |
| pi->cmdtext = p = xmalloc(len); |
| argv = pi->progs[0].argv; |
| do { |
| len = strlen(*argv); |
| memcpy(p, *argv, len); |
| p += len; |
| *p++ = ' '; |
| } while (*++argv); |
| p[-1] = '\0'; |
| return pi->cmdtext; |
| } |
| |
| static void insert_bg_job(struct pipe *pi) |
| { |
| struct pipe *thejob; |
| int i; |
| |
| /* Linear search for the ID of the job to use */ |
| pi->jobid = 1; |
| for (thejob = job_list; thejob; thejob = thejob->next) |
| if (thejob->jobid >= pi->jobid) |
| pi->jobid = thejob->jobid + 1; |
| |
| /* Add thejob to the list of running jobs */ |
| if (!job_list) { |
| thejob = job_list = xmalloc(sizeof(*thejob)); |
| } else { |
| for (thejob = job_list; thejob->next; thejob = thejob->next) |
| continue; |
| thejob->next = xmalloc(sizeof(*thejob)); |
| thejob = thejob->next; |
| } |
| |
| /* Physically copy the struct job */ |
| memcpy(thejob, pi, sizeof(struct pipe)); |
| thejob->progs = xzalloc(sizeof(pi->progs[0]) * pi->num_progs); |
| /* We cannot copy entire pi->progs[] vector! Double free()s will happen */ |
| for (i = 0; i < pi->num_progs; i++) { |
| // TODO: do we really need to have so many fields which are just dead weight |
| // at execution stage? |
| thejob->progs[i].pid = pi->progs[i].pid; |
| /* all other fields are not used and stay zero */ |
| } |
| thejob->next = NULL; |
| thejob->cmdtext = xstrdup(get_cmdtext(pi)); |
| |
| /* We don't wait for background thejobs to return -- append it |
| to the list of backgrounded thejobs and leave it alone */ |
| printf("[%d] %d %s\n", thejob->jobid, thejob->progs[0].pid, thejob->cmdtext); |
| last_bg_pid = thejob->progs[0].pid; |
| last_jobid = thejob->jobid; |
| } |
| |
| static void remove_bg_job(struct pipe *pi) |
| { |
| struct pipe *prev_pipe; |
| |
| if (pi == job_list) { |
| job_list = pi->next; |
| } else { |
| prev_pipe = job_list; |
| while (prev_pipe->next != pi) |
| prev_pipe = prev_pipe->next; |
| prev_pipe->next = pi->next; |
| } |
| if (job_list) |
| last_jobid = job_list->jobid; |
| else |
| last_jobid = 0; |
| } |
| |
| /* remove a backgrounded job */ |
| static void delete_finished_bg_job(struct pipe *pi) |
| { |
| remove_bg_job(pi); |
| pi->stopped_progs = 0; |
| free_pipe(pi, 0); |
| free(pi); |
| } |
| #endif /* JOB */ |
| |
| /* Checks to see if any processes have exited -- if they |
| have, figure out why and see if a job has completed */ |
| static int checkjobs(struct pipe* fg_pipe) |
| { |
| int attributes; |
| int status; |
| #if ENABLE_HUSH_JOB |
| int prognum = 0; |
| struct pipe *pi; |
| #endif |
| pid_t childpid; |
| int rcode = 0; |
| |
| attributes = WUNTRACED; |
| if (fg_pipe == NULL) { |
| attributes |= WNOHANG; |
| } |
| |
| /* Do we do this right? |
| * bash-3.00# sleep 20 | false |
| * <ctrl-Z pressed> |
| * [3]+ Stopped sleep 20 | false |
| * bash-3.00# echo $? |
| * 1 <========== bg pipe is not fully done, but exitcode is already known! |
| */ |
| |
| //FIXME: non-interactive bash does not continue even if all processes in fg pipe |
| //are stopped. Testcase: "cat | cat" in a script (not on command line) |
| // + killall -STOP cat |
| |
| wait_more: |
| // TODO: safe_waitpid? |
| while ((childpid = waitpid(-1, &status, attributes)) > 0) { |
| const int dead = WIFEXITED(status) || WIFSIGNALED(status); |
| |
| #ifdef DEBUG_SHELL_JOBS |
| if (WIFSTOPPED(status)) |
| debug_printf_jobs("pid %d stopped by sig %d (exitcode %d)\n", |
| childpid, WSTOPSIG(status), WEXITSTATUS(status)); |
| if (WIFSIGNALED(status)) |
| debug_printf_jobs("pid %d killed by sig %d (exitcode %d)\n", |
| childpid, WTERMSIG(status), WEXITSTATUS(status)); |
| if (WIFEXITED(status)) |
| debug_printf_jobs("pid %d exited, exitcode %d\n", |
| childpid, WEXITSTATUS(status)); |
| #endif |
| /* Were we asked to wait for fg pipe? */ |
| if (fg_pipe) { |
| int i; |
| for (i = 0; i < fg_pipe->num_progs; i++) { |
| debug_printf_jobs("check pid %d\n", fg_pipe->progs[i].pid); |
| if (fg_pipe->progs[i].pid == childpid) { |
| /* printf("process %d exit %d\n", i, WEXITSTATUS(status)); */ |
| if (dead) { |
| fg_pipe->progs[i].pid = 0; |
| fg_pipe->running_progs--; |
| if (i == fg_pipe->num_progs - 1) |
| /* last process gives overall exitstatus */ |
| rcode = WEXITSTATUS(status); |
| } else { |
| fg_pipe->progs[i].is_stopped = 1; |
| fg_pipe->stopped_progs++; |
| } |
| debug_printf_jobs("fg_pipe: running_progs %d stopped_progs %d\n", |
| fg_pipe->running_progs, fg_pipe->stopped_progs); |
| if (fg_pipe->running_progs - fg_pipe->stopped_progs <= 0) { |
| /* All processes in fg pipe have exited/stopped */ |
| #if ENABLE_HUSH_JOB |
| if (fg_pipe->running_progs) |
| insert_bg_job(fg_pipe); |
| #endif |
| return rcode; |
| } |
| /* There are still running processes in the fg pipe */ |
| goto wait_more; |
| } |
| } |
| /* fall through to searching process in bg pipes */ |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* We asked to wait for bg or orphaned children */ |
| /* No need to remember exitcode in this case */ |
| for (pi = job_list; pi; pi = pi->next) { |
| prognum = 0; |
| while (prognum < pi->num_progs) { |
| if (pi->progs[prognum].pid == childpid) |
| goto found_pi_and_prognum; |
| prognum++; |
| } |
| } |
| #endif |
| |
| /* Happens when shell is used as init process (init=/bin/sh) */ |
| debug_printf("checkjobs: pid %d was not in our list!\n", childpid); |
| goto wait_more; |
| |
| #if ENABLE_HUSH_JOB |
| found_pi_and_prognum: |
| if (dead) { |
| /* child exited */ |
| pi->progs[prognum].pid = 0; |
| pi->running_progs--; |
| if (!pi->running_progs) { |
| printf(JOB_STATUS_FORMAT, pi->jobid, |
| "Done", pi->cmdtext); |
| delete_finished_bg_job(pi); |
| } |
| } else { |
| /* child stopped */ |
| pi->stopped_progs++; |
| pi->progs[prognum].is_stopped = 1; |
| } |
| #endif |
| } |
| |
| /* wait found no children or failed */ |
| |
| if (childpid && errno != ECHILD) |
| bb_perror_msg("waitpid"); |
| return rcode; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| static int checkjobs_and_fg_shell(struct pipe* fg_pipe) |
| { |
| pid_t p; |
| int rcode = checkjobs(fg_pipe); |
| /* Job finished, move the shell to the foreground */ |
| p = getpgid(0); /* pgid of our process */ |
| debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p); |
| if (tcsetpgrp(interactive_fd, p) && errno != ENOTTY) |
| bb_perror_msg("tcsetpgrp-4a"); |
| return rcode; |
| } |
| #endif |
| |
| /* run_pipe() starts all the jobs, but doesn't wait for anything |
| * to finish. See checkjobs(). |
| * |
| * return code is normally -1, when the caller has to wait for children |
| * to finish to determine the exit status of the pipe. If the pipe |
| * is a simple builtin command, however, the action is done by the |
| * time run_pipe returns, and the exit code is provided as the |
| * return value. |
| * |
| * The input of the pipe is always stdin, the output is always |
| * stdout. The outpipe[] mechanism in BusyBox-0.48 lash is bogus, |
| * because it tries to avoid running the command substitution in |
| * subshell, when that is in fact necessary. The subshell process |
| * now has its stdout directed to the input of the appropriate pipe, |
| * so this routine is noticeably simpler. |
| * |
| * Returns -1 only if started some children. IOW: we have to |
| * mask out retvals of builtins etc with 0xff! |
| */ |
| static int run_pipe(struct pipe *pi) |
| { |
| int i; |
| int nextin; |
| int pipefds[2]; /* pipefds[0] is for reading */ |
| struct child_prog *child; |
| const struct built_in_command *x; |
| char *p; |
| /* it is not always needed, but we aim to smaller code */ |
| int squirrel[] = { -1, -1, -1 }; |
| int rcode; |
| const int single_fg = (pi->num_progs == 1 && pi->followup != PIPE_BG); |
| |
| debug_printf_exec("run_pipe start: single_fg=%d\n", single_fg); |
| |
| #if ENABLE_HUSH_JOB |
| pi->pgrp = -1; |
| #endif |
| pi->running_progs = 1; |
| pi->stopped_progs = 0; |
| |
| /* Check if this is a simple builtin (not part of a pipe). |
| * Builtins within pipes have to fork anyway, and are handled in |
| * pseudo_exec. "echo foo | read bar" doesn't work on bash, either. |
| */ |
| child = &(pi->progs[0]); |
| if (single_fg && child->group && child->subshell == 0) { |
| debug_printf("non-subshell grouping\n"); |
| setup_redirects(child, squirrel); |
| debug_printf_exec(": run_list\n"); |
| rcode = run_list(child->group) & 0xff; |
| restore_redirects(squirrel); |
| debug_printf_exec("run_pipe return %d\n", rcode); |
| return rcode; |
| } |
| |
| if (single_fg && child->argv != NULL) { |
| char **argv_expanded; |
| char **argv = child->argv; |
| |
| for (i = 0; is_assignment(argv[i]); i++) |
| continue; |
| if (i != 0 && argv[i] == NULL) { |
| /* assignments, but no command: set the local environment */ |
| for (i = 0; argv[i] != NULL; i++) { |
| debug_printf("local environment set: %s\n", argv[i]); |
| p = expand_string_to_string(argv[i]); |
| set_local_var(p, 0); |
| } |
| return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */ |
| } |
| for (i = 0; is_assignment(argv[i]); i++) { |
| p = expand_string_to_string(argv[i]); |
| //sp: child->sp--; |
| putenv(p); |
| } |
| for (x = bltins; x->cmd; x++) { |
| if (strcmp(argv[i], x->cmd) == 0) { |
| if (x->function == builtin_exec && argv[i+1] == NULL) { |
| debug_printf("magic exec\n"); |
| setup_redirects(child, NULL); |
| return EXIT_SUCCESS; |
| } |
| debug_printf("builtin inline %s\n", argv[0]); |
| /* XXX setup_redirects acts on file descriptors, not FILEs. |
| * This is perfect for work that comes after exec(). |
| * Is it really safe for inline use? Experimentally, |
| * things seem to work with glibc. */ |
| setup_redirects(child, squirrel); |
| debug_printf_exec(": builtin '%s' '%s'...\n", x->cmd, argv[i+1]); |
| //sp: if (child->sp) /* btw we can do it unconditionally... */ |
| argv_expanded = expand_strvec_to_strvec(argv + i); |
| rcode = x->function(argv_expanded) & 0xff; |
| free(argv_expanded); |
| restore_redirects(squirrel); |
| debug_printf_exec("run_pipe return %d\n", rcode); |
| return rcode; |
| } |
| } |
| #if ENABLE_FEATURE_SH_STANDALONE |
| { |
| int a = find_applet_by_name(argv[i]); |
| if (a >= 0 && APPLET_IS_NOFORK(a)) { |
| setup_redirects(child, squirrel); |
| save_nofork_data(&nofork_save); |
| argv_expanded = argv + i; |
| //sp: if (child->sp) |
| argv_expanded = expand_strvec_to_strvec(argv + i); |
| debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]); |
| rcode = run_nofork_applet_prime(&nofork_save, a, argv_expanded) & 0xff; |
| free(argv_expanded); |
| restore_redirects(squirrel); |
| debug_printf_exec("run_pipe return %d\n", rcode); |
| return rcode; |
| } |
| } |
| #endif |
| } |
| |
| /* Disable job control signals for shell (parent) and |
| * for initial child code after fork */ |
| set_jobctrl_sighandler(SIG_IGN); |
| |
| /* Going to fork a child per each pipe member */ |
| pi->running_progs = 0; |
| nextin = 0; |
| |
| for (i = 0; i < pi->num_progs; i++) { |
| child = &(pi->progs[i]); |
| if (child->argv) |
| debug_printf_exec(": pipe member '%s' '%s'...\n", child->argv[0], child->argv[1]); |
| else |
| debug_printf_exec(": pipe member with no argv\n"); |
| |
| /* pipes are inserted between pairs of commands */ |
| pipefds[0] = 0; |
| pipefds[1] = 1; |
| if ((i + 1) < pi->num_progs) |
| xpipe(pipefds); |
| |
| child->pid = BB_MMU ? fork() : vfork(); |
| if (!child->pid) { /* child */ |
| if (ENABLE_HUSH_JOB) |
| die_sleep = 0; /* let nofork's xfuncs die */ |
| #if ENABLE_HUSH_JOB |
| /* Every child adds itself to new process group |
| * with pgid == pid_of_first_child_in_pipe */ |
| if (run_list_level == 1 && interactive_fd) { |
| pid_t pgrp; |
| /* Don't do pgrp restore anymore on fatal signals */ |
| set_fatal_sighandler(SIG_DFL); |
| pgrp = pi->pgrp; |
| if (pgrp < 0) /* true for 1st process only */ |
| pgrp = getpid(); |
| if (setpgid(0, pgrp) == 0 && pi->followup != PIPE_BG) { |
| /* We do it in *every* child, not just first, |
| * to avoid races */ |
| tcsetpgrp(interactive_fd, pgrp); |
| } |
| } |
| #endif |
| xmove_fd(nextin, 0); |
| xmove_fd(pipefds[1], 1); /* write end */ |
| if (pipefds[0] > 1) |
| close(pipefds[0]); /* read end */ |
| /* Like bash, explicit redirects override pipes, |
| * and the pipe fd is available for dup'ing. */ |
| setup_redirects(child, NULL); |
| |
| /* Restore default handlers just prior to exec */ |
| set_jobctrl_sighandler(SIG_DFL); |
| set_misc_sighandler(SIG_DFL); |
| signal(SIGCHLD, SIG_DFL); |
| pseudo_exec(child); /* does not return */ |
| } |
| |
| if (child->pid < 0) { /* [v]fork failed */ |
| /* Clearly indicate, was it fork or vfork */ |
| bb_perror_msg(BB_MMU ? "fork" : "vfork"); |
| } else { |
| pi->running_progs++; |
| #if ENABLE_HUSH_JOB |
| /* Second and next children need to know pid of first one */ |
| if (pi->pgrp < 0) |
| pi->pgrp = child->pid; |
| #endif |
| } |
| |
| if (i) |
| close(nextin); |
| if ((i + 1) < pi->num_progs) |
| close(pipefds[1]); /* write end */ |
| /* Pass read (output) pipe end to next iteration */ |
| nextin = pipefds[0]; |
| } |
| |
| if (!pi->running_progs) { |
| debug_printf_exec("run_pipe return 1 (all forks failed, no children)\n"); |
| return 1; |
| } |
| |
| debug_printf_exec("run_pipe return -1 (%u children started)\n", pi->running_progs); |
| return -1; |
| } |
| |
| #ifndef debug_print_tree |
| static void debug_print_tree(struct pipe *pi, int lvl) |
| { |
| static const char *PIPE[] = { |
| [PIPE_SEQ] = "SEQ", |
| [PIPE_AND] = "AND", |
| [PIPE_OR ] = "OR" , |
| [PIPE_BG ] = "BG" , |
| }; |
| static const char *RES[] = { |
| [RES_NONE ] = "NONE" , |
| #if ENABLE_HUSH_IF |
| [RES_IF ] = "IF" , |
| [RES_THEN ] = "THEN" , |
| [RES_ELIF ] = "ELIF" , |
| [RES_ELSE ] = "ELSE" , |
| [RES_FI ] = "FI" , |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| [RES_FOR ] = "FOR" , |
| [RES_WHILE] = "WHILE", |
| [RES_UNTIL] = "UNTIL", |
| [RES_DO ] = "DO" , |
| [RES_DONE ] = "DONE" , |
| [RES_IN ] = "IN" , |
| #endif |
| [RES_XXXX ] = "XXXX" , |
| [RES_SNTX ] = "SNTX" , |
| }; |
| |
| int pin, prn; |
| |
| pin = 0; |
| while (pi) { |
| fprintf(stderr, "%*spipe %d res_word=%s followup=%d %s\n", lvl*2, "", |
| pin, RES[pi->res_word], pi->followup, PIPE[pi->followup]); |
| prn = 0; |
| while (prn < pi->num_progs) { |
| struct child_prog *child = &pi->progs[prn]; |
| char **argv = child->argv; |
| |
| fprintf(stderr, "%*s prog %d", lvl*2, "", prn); |
| if (child->group) { |
| fprintf(stderr, " group %s: (argv=%p)\n", |
| (child->subshell ? "()" : "{}"), |
| argv); |
| debug_print_tree(child->group, lvl+1); |
| prn++; |
| continue; |
| } |
| if (argv) while (*argv) { |
| fprintf(stderr, " '%s'", *argv); |
| argv++; |
| } |
| fprintf(stderr, "\n"); |
| prn++; |
| } |
| pi = pi->next; |
| pin++; |
| } |
| } |
| #endif |
| |
| /* NB: called by pseudo_exec, and therefore must not modify any |
| * global data until exec/_exit (we can be a child after vfork!) */ |
| static int run_list(struct pipe *pi) |
| { |
| struct pipe *rpipe; |
| #if ENABLE_HUSH_LOOPS |
| char *for_varname = NULL; |
| char **for_lcur = NULL; |
| char **for_list = NULL; |
| int flag_rep = 0; |
| #endif |
| int flag_skip = 1; |
| int rcode = 0; /* probably for gcc only */ |
| int flag_restore = 0; |
| #if ENABLE_HUSH_IF |
| int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */ |
| #else |
| enum { if_code = 0, next_if_code = 0 }; |
| #endif |
| reserved_style rword; |
| reserved_style skip_more_for_this_rword = RES_XXXX; |
| |
| debug_printf_exec("run_list start lvl %d\n", run_list_level + 1); |
| |
| #if ENABLE_HUSH_LOOPS |
| /* check syntax for "for" */ |
| for (rpipe = pi; rpipe; rpipe = rpipe->next) { |
| if ((rpipe->res_word == RES_IN || rpipe->res_word == RES_FOR) |
| && (rpipe->next == NULL) |
| ) { |
| syntax("malformed for"); /* no IN or no commands after IN */ |
| debug_printf_exec("run_list lvl %d return 1\n", run_list_level); |
| return 1; |
| } |
| if ((rpipe->res_word == RES_IN && rpipe->next->res_word == RES_IN && rpipe->next->progs[0].argv != NULL) |
| || (rpipe->res_word == RES_FOR && rpipe->next->res_word != RES_IN) |
| ) { |
| /* TODO: what is tested in the first condition? */ |
| syntax("malformed for"); /* 2nd condition: not followed by IN */ |
| debug_printf_exec("run_list lvl %d return 1\n", run_list_level); |
| return 1; |
| } |
| } |
| #else |
| rpipe = NULL; |
| #endif |
| |
| #if ENABLE_HUSH_JOB |
| /* Example of nested list: "while true; do { sleep 1 | exit 2; } done". |
| * We are saving state before entering outermost list ("while...done") |
| * so that ctrl-Z will correctly background _entire_ outermost list, |
| * not just a part of it (like "sleep 1 | exit 2") */ |
| if (++run_list_level == 1 && interactive_fd) { |
| if (sigsetjmp(toplevel_jb, 1)) { |
| /* ctrl-Z forked and we are parent; or ctrl-C. |
| * Sighandler has longjmped us here */ |
| signal(SIGINT, SIG_IGN); |
| signal(SIGTSTP, SIG_IGN); |
| /* Restore level (we can be coming from deep inside |
| * nested levels) */ |
| run_list_level = 1; |
| #if ENABLE_FEATURE_SH_STANDALONE |
| if (nofork_save.saved) { /* if save area is valid */ |
| debug_printf_jobs("exiting nofork early\n"); |
| restore_nofork_data(&nofork_save); |
| } |
| #endif |
| if (ctrl_z_flag) { |
| /* ctrl-Z has forked and stored pid of the child in pi->pid. |
| * Remember this child as background job */ |
| insert_bg_job(pi); |
| } else { |
| /* ctrl-C. We just stop doing whatever we were doing */ |
| bb_putchar('\n'); |
| } |
| rcode = 0; |
| goto ret; |
| } |
| /* ctrl-Z handler will store pid etc in pi */ |
| toplevel_list = pi; |
| ctrl_z_flag = 0; |
| #if ENABLE_FEATURE_SH_STANDALONE |
| nofork_save.saved = 0; /* in case we will run a nofork later */ |
| #endif |
| signal_SA_RESTART_empty_mask(SIGTSTP, handler_ctrl_z); |
| signal(SIGINT, handler_ctrl_c); |
| } |
| #endif /* JOB */ |
| |
| for (; pi; pi = flag_restore ? rpipe : pi->next) { |
| //why? int save_num_progs; |
| rword = pi->res_word; |
| #if ENABLE_HUSH_LOOPS |
| if (rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR) { |
| flag_restore = 0; |
| if (!rpipe) { |
| flag_rep = 0; |
| rpipe = pi; |
| } |
| } |
| #endif |
| debug_printf_exec(": rword=%d if_code=%d next_if_code=%d skip_more=%d\n", |
| rword, if_code, next_if_code, skip_more_for_this_rword); |
| if (rword == skip_more_for_this_rword && flag_skip) { |
| if (pi->followup == PIPE_SEQ) |
| flag_skip = 0; |
| continue; |
| } |
| flag_skip = 1; |
| skip_more_for_this_rword = RES_XXXX; |
| #if ENABLE_HUSH_IF |
| if (rword == RES_THEN || rword == RES_ELSE) |
| if_code = next_if_code; |
| if (rword == RES_THEN && if_code) |
| continue; |
| if (rword == RES_ELSE && !if_code) |
| continue; |
| if (rword == RES_ELIF && !if_code) |
| break; |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| if (rword == RES_FOR && pi->num_progs) { |
| if (!for_lcur) { |
| /* first loop through for */ |
| /* if no variable values after "in" we skip "for" */ |
| if (!pi->next->progs->argv) |
| continue; |
| /* create list of variable values */ |
| for_list = expand_strvec_to_strvec(pi->next->progs->argv); |
| for_lcur = for_list; |
| for_varname = pi->progs->argv[0]; |
| pi->progs->argv[0] = NULL; |
| flag_rep = 1; |
| } |
| free(pi->progs->argv[0]); |
| if (!*for_lcur) { |
| /* for loop is over, clean up */ |
| free(for_list); |
| for_lcur = NULL; |
| flag_rep = 0; |
| pi->progs->argv[0] = for_varname; |
| continue; |
| } |
| /* insert next value from for_lcur */ |
| /* vda: does it need escaping? */ |
| pi->progs->argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++); |
| } |
| if (rword == RES_IN) |
| continue; |
| if (rword == RES_DO) { |
| if (!flag_rep) |
| continue; |
| } |
| if (rword == RES_DONE) { |
| if (flag_rep) { |
| flag_restore = 1; |
| } else { |
| rpipe = NULL; |
| } |
| } |
| #endif |
| if (pi->num_progs == 0) |
| continue; |
| //why? save_num_progs = pi->num_progs; |
| debug_printf_exec(": run_pipe with %d members\n", pi->num_progs); |
| rcode = run_pipe(pi); |
| if (rcode != -1) { |
| /* We only ran a builtin: rcode was set by the return value |
| * of run_pipe(), and we don't need to wait for anything. */ |
| } else if (pi->followup == PIPE_BG) { |
| /* What does bash do with attempts to background builtins? */ |
| /* Even bash 3.2 doesn't do that well with nested bg: |
| * try "{ { sleep 10; echo DEEP; } & echo HERE; } &". |
| * I'm NOT treating inner &'s as jobs */ |
| #if ENABLE_HUSH_JOB |
| if (run_list_level == 1) |
| insert_bg_job(pi); |
| #endif |
| rcode = EXIT_SUCCESS; |
| } else { |
| #if ENABLE_HUSH_JOB |
| if (run_list_level == 1 && interactive_fd) { |
| /* waits for completion, then fg's main shell */ |
| rcode = checkjobs_and_fg_shell(pi); |
| } else |
| #endif |
| { |
| /* this one just waits for completion */ |
| rcode = checkjobs(pi); |
| } |
| debug_printf_exec(": checkjobs returned %d\n", rcode); |
| } |
| debug_printf_exec(": setting last_return_code=%d\n", rcode); |
| last_return_code = rcode; |
| //why? pi->num_progs = save_num_progs; |
| #if ENABLE_HUSH_IF |
| if (rword == RES_IF || rword == RES_ELIF) |
| next_if_code = rcode; /* can be overwritten a number of times */ |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| if (rword == RES_WHILE) |
| flag_rep = !last_return_code; |
| if (rword == RES_UNTIL) |
| flag_rep = last_return_code; |
| #endif |
| if ((rcode == EXIT_SUCCESS && pi->followup == PIPE_OR) |
| || (rcode != EXIT_SUCCESS && pi->followup == PIPE_AND) |
| ) { |
| skip_more_for_this_rword = rword; |
| } |
| checkjobs(NULL); |
| } |
| |
| #if ENABLE_HUSH_JOB |
| if (ctrl_z_flag) { |
| /* ctrl-Z forked somewhere in the past, we are the child, |
| * and now we completed running the list. Exit. */ |
| exit(rcode); |
| } |
| ret: |
| if (!--run_list_level && interactive_fd) { |
| signal(SIGTSTP, SIG_IGN); |
| signal(SIGINT, SIG_IGN); |
| } |
| #endif |
| debug_printf_exec("run_list lvl %d return %d\n", run_list_level + 1, rcode); |
| return rcode; |
| } |
| |
| /* return code is the exit status of the pipe */ |
| static int free_pipe(struct pipe *pi, int indent) |
| { |
| char **p; |
| struct child_prog *child; |
| struct redir_struct *r, *rnext; |
| int a, i, ret_code = 0; |
| |
| if (pi->stopped_progs > 0) |
| return ret_code; |
| debug_printf_clean("%s run pipe: (pid %d)\n", indenter(indent), getpid()); |
| for (i = 0; i < pi->num_progs; i++) { |
| child = &pi->progs[i]; |
| debug_printf_clean("%s command %d:\n", indenter(indent), i); |
| if (child->argv) { |
| for (a = 0, p = child->argv; *p; a++, p++) { |
| debug_printf_clean("%s argv[%d] = %s\n", indenter(indent), a, *p); |
| } |
| free_strings(child->argv); |
| child->argv = NULL; |
| } else if (child->group) { |
| debug_printf_clean("%s begin group (subshell:%d)\n", indenter(indent), child->subshell); |
| ret_code = free_pipe_list(child->group, indent+3); |
| debug_printf_clean("%s end group\n", indenter(indent)); |
| } else { |
| debug_printf_clean("%s (nil)\n", indenter(indent)); |
| } |
| for (r = child->redirects; r; r = rnext) { |
| debug_printf_clean("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->type].descrip); |
| if (r->dup == -1) { |
| /* guard against the case >$FOO, where foo is unset or blank */ |
| if (r->glob_word) { |
| debug_printf_clean(" %s\n", r->glob_word[0]); |
| free_strings(r->glob_word); |
| r->glob_word = NULL; |
| } |
| } else { |
| debug_printf_clean("&%d\n", r->dup); |
| } |
| rnext = r->next; |
| free(r); |
| } |
| child->redirects = NULL; |
| } |
| free(pi->progs); /* children are an array, they get freed all at once */ |
| pi->progs = NULL; |
| #if ENABLE_HUSH_JOB |
| free(pi->cmdtext); |
| pi->cmdtext = NULL; |
| #endif |
| return ret_code; |
| } |
| |
| static int free_pipe_list(struct pipe *head, int indent) |
| { |
| int rcode = 0; /* if list has no members */ |
| struct pipe *pi, *next; |
| |
| for (pi = head; pi; pi = next) { |
| debug_printf_clean("%s pipe reserved mode %d\n", indenter(indent), pi->res_word); |
| rcode = free_pipe(pi, indent); |
| debug_printf_clean("%s pipe followup code %d\n", indenter(indent), pi->followup); |
| next = pi->next; |
| /*pi->next = NULL;*/ |
| free(pi); |
| } |
| return rcode; |
| } |
| |
| /* Select which version we will use */ |
| static int run_and_free_list(struct pipe *pi) |
| { |
| int rcode = 0; |
| debug_printf_exec("run_and_free_list entered\n"); |
| if (!fake_mode) { |
| debug_printf_exec(": run_list with %d members\n", pi->num_progs); |
| rcode = run_list(pi); |
| } |
| /* free_pipe_list has the side effect of clearing memory. |
| * In the long run that function can be merged with run_list, |
| * but doing that now would hobble the debugging effort. */ |
| free_pipe_list(pi, /* indent: */ 0); |
| debug_printf_exec("run_nad_free_list return %d\n", rcode); |
| return rcode; |
| } |
| |
| /* Whoever decided to muck with glob internal data is AN IDIOT! */ |
| /* uclibc happily changed the way it works (and it has rights to do so!), |
| all hell broke loose (SEGVs) */ |
| |
| /* The API for glob is arguably broken. This routine pushes a non-matching |
| * string into the output structure, removing non-backslashed backslashes. |
| * If someone can prove me wrong, by performing this function within the |
| * original glob(3) api, feel free to rewrite this routine into oblivion. |
| * XXX broken if the last character is '\\', check that before calling. |
| */ |
| static char **globhack(const char *src, char **strings) |
| { |
| int cnt; |
| const char *s; |
| char *v, *dest; |
| |
| for (cnt = 1, s = src; s && *s; s++) { |
| if (*s == '\\') s++; |
| cnt++; |
| } |
| v = dest = xmalloc(cnt); |
| for (s = src; s && *s; s++, dest++) { |
| if (*s == '\\') s++; |
| *dest = *s; |
| } |
| *dest = '\0'; |
| |
| return add_string_to_strings(strings, v); |
| } |
| |
| /* XXX broken if the last character is '\\', check that before calling */ |
| static int glob_needed(const char *s) |
| { |
| for (; *s; s++) { |
| if (*s == '\\') |
| s++; |
| if (strchr("*[?", *s)) |
| return 1; |
| } |
| return 0; |
| } |
| |
| static int xglob(o_string *dest, char ***pglob) |
| { |
| /* short-circuit for null word */ |
| /* we can code this better when the debug_printf's are gone */ |
| if (dest->length == 0) { |
| if (dest->nonnull) { |
| /* bash man page calls this an "explicit" null */ |
| *pglob = globhack(dest->data, *pglob); |
| } |
| return 0; |
| } |
| |
| if (glob_needed(dest->data)) { |
| glob_t globdata; |
| int gr; |
| |
| memset(&globdata, 0, sizeof(globdata)); |
| gr = glob(dest->data, 0, NULL, &globdata); |
| debug_printf("glob returned %d\n", gr); |
| if (gr == GLOB_NOSPACE) |
| bb_error_msg_and_die("out of memory during glob"); |
| if (gr == GLOB_NOMATCH) { |
| debug_printf("globhack returned %d\n", gr); |
| /* quote removal, or more accurately, backslash removal */ |
| *pglob = globhack(dest->data, *pglob); |
| globfree(&globdata); |
| return 0; |
| } |
| if (gr != 0) { /* GLOB_ABORTED ? */ |
| bb_error_msg("glob(3) error %d", gr); |
| } |
| if (globdata.gl_pathv && globdata.gl_pathv[0]) |
| *pglob = add_strings_to_strings(1, *pglob, globdata.gl_pathv); |
| globfree(&globdata); |
| return gr; |
| } |
| |
| *pglob = globhack(dest->data, *pglob); |
| return 0; |
| } |
| |
| /* expand_strvec_to_strvec() takes a list of strings, expands |
| * all variable references within and returns a pointer to |
| * a list of expanded strings, possibly with larger number |
| * of strings. (Think VAR="a b"; echo $VAR). |
| * This new list is allocated as a single malloc block. |
| * NULL-terminated list of char* pointers is at the beginning of it, |
| * followed by strings themself. |
| * Caller can deallocate entire list by single free(list). */ |
| |
| /* Helpers first: |
| * count_XXX estimates size of the block we need. It's okay |
| * to over-estimate sizes a bit, if it makes code simpler */ |
| static int count_ifs(const char *str) |
| { |
| int cnt = 0; |
| debug_printf_expand("count_ifs('%s') ifs='%s'", str, ifs); |
| while (1) { |
| str += strcspn(str, ifs); |
| if (!*str) break; |
| str++; /* str += strspn(str, ifs); */ |
| cnt++; /* cnt += strspn(str, ifs); - but this code is larger */ |
| } |
| debug_printf_expand(" return %d\n", cnt); |
| return cnt; |
| } |
| |
| static void count_var_expansion_space(int *countp, int *lenp, char *arg) |
| { |
| char first_ch; |
| int i; |
| int len = *lenp; |
| int count = *countp; |
| const char *val; |
| char *p; |
| |
| while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) { |
| len += p - arg; |
| arg = ++p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| first_ch = arg[0]; |
| |
| switch (first_ch & 0x7f) { |
| /* high bit in 1st_ch indicates that var is double-quoted */ |
| case '$': /* pid */ |
| case '!': /* bg pid */ |
| case '?': /* exitcode */ |
| case '#': /* argc */ |
| len += sizeof(int)*3 + 1; /* enough for int */ |
| break; |
| case '*': |
| case '@': |
| for (i = 1; global_argv[i]; i++) { |
| len += strlen(global_argv[i]) + 1; |
| count++; |
| if (!(first_ch & 0x80)) |
| count += count_ifs(global_argv[i]); |
| } |
| break; |
| default: |
| *p = '\0'; |
| arg[0] = first_ch & 0x7f; |
| if (isdigit(arg[0])) { |
| i = xatoi_u(arg); |
| val = NULL; |
| if (i < global_argc) |
| val = global_argv[i]; |
| } else |
| val = lookup_param(arg); |
| arg[0] = first_ch; |
| *p = SPECIAL_VAR_SYMBOL; |
| |
| if (val) { |
| len += strlen(val) + 1; |
| if (!(first_ch & 0x80)) |
| count += count_ifs(val); |
| } |
| } |
| arg = ++p; |
| } |
| |
| len += strlen(arg) + 1; |
| count++; |
| *lenp = len; |
| *countp = count; |
| } |
| |
| /* Store given string, finalizing the word and starting new one whenever |
| * we encounter ifs char(s). This is used for expanding variable values. |
| * End-of-string does NOT finalize word: think about 'echo -$VAR-' */ |
| static int expand_on_ifs(char **list, int n, char **posp, const char *str) |
| { |
| char *pos = *posp; |
| while (1) { |
| int word_len = strcspn(str, ifs); |
| if (word_len) { |
| memcpy(pos, str, word_len); /* store non-ifs chars */ |
| pos += word_len; |
| str += word_len; |
| } |
| if (!*str) /* EOL - do not finalize word */ |
| break; |
| *pos++ = '\0'; |
| if (n) debug_printf_expand("expand_on_ifs finalized list[%d]=%p '%s' " |
| "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], |
| strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); |
| list[n++] = pos; |
| str += strspn(str, ifs); /* skip ifs chars */ |
| } |
| *posp = pos; |
| return n; |
| } |
| |
| /* Expand all variable references in given string, adding words to list[] |
| * at n, n+1,... positions. Return updated n (so that list[n] is next one |
| * to be filled). This routine is extremely tricky: has to deal with |
| * variables/parameters with whitespace, $* and $@, and constructs like |
| * 'echo -$*-'. If you play here, you must run testsuite afterwards! */ |
| /* NB: another bug is that we cannot detect empty strings yet: |
| * "" or $empty"" expands to zero words, has to expand to empty word */ |
| static int expand_vars_to_list(char **list, int n, char **posp, char *arg, char or_mask) |
| { |
| /* or_mask is either 0 (normal case) or 0x80 |
| * (expansion of right-hand side of assignment == 1-element expand) */ |
| |
| char first_ch, ored_ch; |
| int i; |
| const char *val; |
| char *p; |
| char *pos = *posp; |
| |
| ored_ch = 0; |
| |
| if (n) debug_printf_expand("expand_vars_to_list finalized list[%d]=%p '%s' " |
| "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], |
| strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); |
| list[n++] = pos; |
| |
| while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) { |
| memcpy(pos, arg, p - arg); |
| pos += (p - arg); |
| arg = ++p; |
| p = strchr(p, SPECIAL_VAR_SYMBOL); |
| |
| first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */ |
| ored_ch |= first_ch; |
| val = NULL; |
| switch (first_ch & 0x7f) { |
| /* Highest bit in first_ch indicates that var is double-quoted */ |
| case '$': /* pid */ |
| /* FIXME: (echo $$) should still print pid of main shell */ |
| val = utoa(getpid()); /* rootpid? */ |
| break; |
| case '!': /* bg pid */ |
| val = last_bg_pid ? utoa(last_bg_pid) : (char*)""; |
| break; |
| case '?': /* exitcode */ |
| val = utoa(last_return_code); |
| break; |
| case '#': /* argc */ |
| val = utoa(global_argc ? global_argc-1 : 0); |
| break; |
| case '*': |
| case '@': |
| i = 1; |
| if (!global_argv[i]) |
| break; |
| if (!(first_ch & 0x80)) { /* unquoted $* or $@ */ |
| while (global_argv[i]) { |
| n = expand_on_ifs(list, n, &pos, global_argv[i]); |
| debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, global_argc-1); |
| if (global_argv[i++][0] && global_argv[i]) { |
| /* this argv[] is not empty and not last: |
| * put terminating NUL, start new word */ |
| *pos++ = '\0'; |
| if (n) debug_printf_expand("expand_vars_to_list 2 finalized list[%d]=%p '%s' " |
| "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], |
| strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); |
| list[n++] = pos; |
| } |
| } |
| } else |
| /* If or_mask is nonzero, we handle assignment 'a=....$@.....' |
| * and in this case should treat it like '$*' - see 'else...' below */ |
| if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */ |
| while (1) { |
| strcpy(pos, global_argv[i]); |
| pos += strlen(global_argv[i]); |
| if (++i >= global_argc) |
| break; |
| *pos++ = '\0'; |
| if (n) debug_printf_expand("expand_vars_to_list 3 finalized list[%d]=%p '%s' " |
| "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], |
| strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); |
| list[n++] = pos; |
| } |
| } else { /* quoted $*: add as one word */ |
| while (1) { |
| strcpy(pos, global_argv[i]); |
| pos += strlen(global_argv[i]); |
| if (!global_argv[++i]) |
| break; |
| if (ifs[0]) |
| *pos++ = ifs[0]; |
| } |
| } |
| break; |
| default: |
| *p = '\0'; |
| arg[0] = first_ch & 0x7f; |
| if (isdigit(arg[0])) { |
| i = xatoi_u(arg); |
| val = NULL; |
| if (i < global_argc) |
| val = global_argv[i]; |
| } else |
| val = lookup_param(arg); |
| arg[0] = first_ch; |
| *p = SPECIAL_VAR_SYMBOL; |
| if (!(first_ch & 0x80)) { /* unquoted $VAR */ |
| if (val) { |
| n = expand_on_ifs(list, n, &pos, val); |
| val = NULL; |
| } |
| } /* else: quoted $VAR, val will be appended at pos */ |
| } |
| if (val) { |
| strcpy(pos, val); |
| pos += strlen(val); |
| } |
| arg = ++p; |
| } |
| debug_printf_expand("expand_vars_to_list adding tail '%s' at %p\n", arg, pos); |
| strcpy(pos, arg); |
| pos += strlen(arg) + 1; |
| if (pos == list[n-1] + 1) { /* expansion is empty */ |
| if (!(ored_ch & 0x80)) { /* all vars were not quoted... */ |
| debug_printf_expand("expand_vars_to_list list[%d] empty, going back\n", n); |
| pos--; |
| n--; |
| } |
| } |
| |
| *posp = pos; |
| return n; |
| } |
| |
| static char **expand_variables(char **argv, char or_mask) |
| { |
| int n; |
| int count = 1; |
| int len = 0; |
| char *pos, **v, **list; |
| |
| v = argv; |
| if (!*v) debug_printf_expand("count_var_expansion_space: " |
| "argv[0]=NULL count=%d len=%d alloc_space=%d\n", |
| count, len, sizeof(char*) * count + len); |
| while (*v) { |
| count_var_expansion_space(&count, &len, *v); |
| debug_printf_expand("count_var_expansion_space: " |
| "'%s' count=%d len=%d alloc_space=%d\n", |
| *v, count, len, sizeof(char*) * count + len); |
| v++; |
| } |
| len += sizeof(char*) * count; /* total to alloc */ |
| list = xmalloc(len); |
| pos = (char*)(list + count); |
| debug_printf_expand("list=%p, list[0] should be %p\n", list, pos); |
| n = 0; |
| v = argv; |
| while (*v) |
| n = expand_vars_to_list(list, n, &pos, *v++, or_mask); |
| |
| if (n) debug_printf_expand("finalized list[%d]=%p '%s' " |
| "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], |
| strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); |
| list[n] = NULL; |
| |
| #ifdef DEBUG_EXPAND |
| { |
| int m = 0; |
| while (m <= n) { |
| debug_printf_expand("list[%d]=%p '%s'\n", m, list[m], list[m]); |
| m++; |
| } |
| debug_printf_expand("used_space=%d\n", pos - (char*)list); |
| } |
| #endif |
| if (ENABLE_HUSH_DEBUG) |
| if (pos - (char*)list > len) |
| bb_error_msg_and_die("BUG in varexp"); |
| return list; |
| } |
| |
| static char **expand_strvec_to_strvec(char **argv) |
| { |
| return expand_variables(argv, 0); |
| } |
| |
| static char *expand_string_to_string(const char *str) |
| { |
| char *argv[2], **list; |
| |
| argv[0] = (char*)str; |
| argv[1] = NULL; |
| list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */ |
| if (ENABLE_HUSH_DEBUG) |
| if (!list[0] || list[1]) |
| bb_error_msg_and_die("BUG in varexp2"); |
| /* actually, just move string 2*sizeof(char*) bytes back */ |
| strcpy((char*)list, list[0]); |
| debug_printf_expand("string_to_string='%s'\n", (char*)list); |
| return (char*)list; |
| } |
| |
| static char* expand_strvec_to_string(char **argv) |
| { |
| char **list; |
| |
| list = expand_variables(argv, 0x80); |
| /* Convert all NULs to spaces */ |
| if (list[0]) { |
| int n = 1; |
| while (list[n]) { |
| if (ENABLE_HUSH_DEBUG) |
| if (list[n-1] + strlen(list[n-1]) + 1 != list[n]) |
| bb_error_msg_and_die("BUG in varexp3"); |
| list[n][-1] = ' '; /* TODO: or to ifs[0]? */ |
| n++; |
| } |
| } |
| strcpy((char*)list, list[0]); |
| debug_printf_expand("strvec_to_string='%s'\n", (char*)list); |
| return (char*)list; |
| } |
| |
| /* This is used to get/check local shell variables */ |
| static struct variable *get_local_var(const char *name) |
| { |
| struct variable *cur; |
| int len; |
| |
| if (!name) |
| return NULL; |
| len = strlen(name); |
| for (cur = top_var; cur; cur = cur->next) { |
| if (strncmp(cur->varstr, name, len) == 0 && cur->varstr[len] == '=') |
| return cur; |
| } |
| return NULL; |
| } |
| |
| /* str holds "NAME=VAL" and is expected to be malloced. |
| * We take ownership of it. */ |
| static int set_local_var(char *str, int flg_export) |
| { |
| struct variable *cur; |
| char *value; |
| int name_len; |
| |
| value = strchr(str, '='); |
| if (!value) { /* not expected to ever happen? */ |
| free(str); |
| return -1; |
| } |
| |
| name_len = value - str + 1; /* including '=' */ |
| cur = top_var; /* cannot be NULL (we have HUSH_VERSION and it's RO) */ |
| while (1) { |
| if (strncmp(cur->varstr, str, name_len) != 0) { |
| if (!cur->next) { |
| /* Bail out. Note that now cur points |
| * to last var in linked list */ |
| break; |
| } |
| cur = cur->next; |
| continue; |
| } |
| /* We found an existing var with this name */ |
| *value = '\0'; |
| if (cur->flg_read_only) { |
| bb_error_msg("%s: readonly variable", str); |
| free(str); |
| return -1; |
| } |
| unsetenv(str); /* just in case */ |
| *value = '='; |
| if (strcmp(cur->varstr, str) == 0) { |
| free_and_exp: |
| free(str); |
| goto exp; |
| } |
| if (cur->max_len >= strlen(str)) { |
| /* This one is from startup env, reuse space */ |
| strcpy(cur->varstr, str); |
| goto free_and_exp; |
| } |
| /* max_len == 0 signifies "malloced" var, which we can |
| * (and has to) free */ |
| if (!cur->max_len) |
| free(cur->varstr); |
| cur->max_len = 0; |
| goto set_str_and_exp; |
| } |
| |
| /* Not found - create next variable struct */ |
| cur->next = xzalloc(sizeof(*cur)); |
| cur = cur->next; |
| |
| set_str_and_exp: |
| cur->varstr = str; |
| exp: |
| if (flg_export) |
| cur->flg_export = 1; |
| if (cur->flg_export) |
| return putenv(cur->varstr); |
| return 0; |
| } |
| |
| static void unset_local_var(const char *name) |
| { |
| struct variable *cur; |
| struct variable *prev = prev; /* for gcc */ |
| int name_len; |
| |
| if (!name) |
| return; |
| name_len = strlen(name); |
| cur = top_var; |
| while (cur) { |
| if (strncmp(cur->varstr, name, name_len) == 0 && cur->varstr[name_len] == '=') { |
| if (cur->flg_read_only) { |
| bb_error_msg("%s: readonly variable", name); |
| return; |
| } |
| /* prev is ok to use here because 1st variable, HUSH_VERSION, |
| * is ro, and we cannot reach this code on the 1st pass */ |
| prev->next = cur->next; |
| unsetenv(cur->varstr); |
| if (!cur->max_len) |
| free(cur->varstr); |
| free(cur); |
| return; |
| } |
| prev = cur; |
| cur = cur->next; |
| } |
| } |
| |
| static int is_assignment(const char *s) |
| { |
| if (!s || !isalpha(*s)) |
| return 0; |
| s++; |
| while (isalnum(*s) || *s == '_') |
| s++; |
| return *s == '='; |
| } |
| |
| /* the src parameter allows us to peek forward to a possible &n syntax |
| * for file descriptor duplication, e.g., "2>&1". |
| * Return code is 0 normally, 1 if a syntax error is detected in src. |
| * Resource errors (in xmalloc) cause the process to exit */ |
| static int setup_redirect(struct p_context *ctx, int fd, redir_type style, |
| struct in_str *input) |
| { |
| struct child_prog *child = ctx->child; |
| struct redir_struct *redir = child->redirects; |
| struct redir_struct *last_redir = NULL; |
| |
| /* Create a new redir_struct and drop it onto the end of the linked list */ |
| while (redir) { |
| last_redir = redir; |
| redir = redir->next; |
| } |
| redir = xzalloc(sizeof(struct redir_struct)); |
| /* redir->next = NULL; */ |
| /* redir->glob_word = NULL; */ |
| if (last_redir) { |
| last_redir->next = redir; |
| } else { |
| child->redirects = redir; |
| } |
| |
| redir->type = style; |
| redir->fd = (fd == -1) ? redir_table[style].default_fd : fd; |
| |
| debug_printf("Redirect type %d%s\n", redir->fd, redir_table[style].descrip); |
| |
| /* Check for a '2>&1' type redirect */ |
| redir->dup = redirect_dup_num(input); |
| if (redir->dup == -2) return 1; /* syntax error */ |
| if (redir->dup != -1) { |
| /* Erik had a check here that the file descriptor in question |
| * is legit; I postpone that to "run time" |
| * A "-" representation of "close me" shows up as a -3 here */ |
| debug_printf("Duplicating redirect '%d>&%d'\n", redir->fd, redir->dup); |
| } else { |
| /* We do _not_ try to open the file that src points to, |
| * since we need to return and let src be expanded first. |
| * Set ctx->pending_redirect, so we know what to do at the |
| * end of the next parsed word. */ |
| ctx->pending_redirect = redir; |
| } |
| return 0; |
| } |
| |
| static struct pipe *new_pipe(void) |
| { |
| struct pipe *pi; |
| pi = xzalloc(sizeof(struct pipe)); |
| /*pi->num_progs = 0;*/ |
| /*pi->progs = NULL;*/ |
| /*pi->next = NULL;*/ |
| /*pi->followup = 0; invalid */ |
| if (RES_NONE) |
| pi->res_word = RES_NONE; |
| return pi; |
| } |
| |
| static void initialize_context(struct p_context *ctx) |
| { |
| ctx->child = NULL; |
| ctx->pipe = ctx->list_head = new_pipe(); |
| ctx->pending_redirect = NULL; |
| ctx->res_w = RES_NONE; |
| //only ctx->parse_type is not touched... is this intentional? |
| ctx->old_flag = 0; |
| ctx->stack = NULL; |
| done_command(ctx); /* creates the memory for working child */ |
| } |
| |
| /* normal return is 0 |
| * if a reserved word is found, and processed, return 1 |
| * should handle if, then, elif, else, fi, for, while, until, do, done. |
| * case, function, and select are obnoxious, save those for later. |
| */ |
| #if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS |
| static int reserved_word(o_string *dest, struct p_context *ctx) |
| { |
| struct reserved_combo { |
| char literal[7]; |
| unsigned char code; |
| int flag; |
| }; |
| /* Mostly a list of accepted follow-up reserved words. |
| * FLAG_END means we are done with the sequence, and are ready |
| * to turn the compound list into a command. |
| * FLAG_START means the word must start a new compound list. |
| */ |
| static const struct reserved_combo reserved_list[] = { |
| #if ENABLE_HUSH_IF |
| { "if", RES_IF, FLAG_THEN | FLAG_START }, |
| { "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI }, |
| { "elif", RES_ELIF, FLAG_THEN }, |
| { "else", RES_ELSE, FLAG_FI }, |
| { "fi", RES_FI, FLAG_END }, |
| #endif |
| #if ENABLE_HUSH_LOOPS |
| { "for", RES_FOR, FLAG_IN | FLAG_START }, |
| { "while", RES_WHILE, FLAG_DO | FLAG_START }, |
| { "until", RES_UNTIL, FLAG_DO | FLAG_START }, |
| { "in", RES_IN, FLAG_DO }, |
| { "do", RES_DO, FLAG_DONE }, |
| { "done", RES_DONE, FLAG_END } |
| #endif |
| }; |
| |
| const struct reserved_combo *r; |
| |
| for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) { |
| if (strcmp(dest->data, r->literal) != 0) |
| continue; |
| debug_printf("found reserved word %s, code %d\n", r->literal, r->code); |
| if (r->flag & FLAG_START) { |
| struct p_context *new; |
| debug_printf("push stack\n"); |
| #if ENABLE_HUSH_LOOPS |
| if (ctx->res_w == RES_IN || ctx->res_w == RES_FOR) { |
| syntax("malformed for"); /* example: 'for if' */ |
| ctx->res_w = RES_SNTX; |
| b_reset(dest); |
| return 1; |
| } |
| #endif |
| new = xmalloc(sizeof(*new)); |
| *new = *ctx; /* physical copy */ |
| initialize_context(ctx); |
| ctx->stack = new; |
| } else if (ctx->res_w == RES_NONE || !(ctx->old_flag & (1 << r->code))) { |
| syntax(NULL); |
| ctx->res_w = RES_SNTX; |
| b_reset(dest); |
| return 1; |
| } |
| ctx->res_w = r->code; |
| ctx->old_flag = r->flag; |
| if (ctx->old_flag & FLAG_END) { |
| struct p_context *old; |
| debug_printf("pop stack\n"); |
| done_pipe(ctx, PIPE_SEQ); |
| old = ctx->stack; |
| old->child->group = ctx->list_head; |
| old->child->subshell = 0; |
| *ctx = *old; /* physical copy */ |
| free(old); |
| } |
| b_reset(dest); |
| return 1; |
| } |
| return 0; |
| } |
| #else |
| #define reserved_word(dest, ctx) ((int)0) |
| #endif |
| |
| /* Normal return is 0. |
| * Syntax or xglob errors return 1. */ |
| static int done_word(o_string *dest, struct p_context *ctx) |
| { |
| struct child_prog *child = ctx->child; |
| char ***glob_target; |
| int gr; |
| |
| debug_printf_parse("done_word entered: '%s' %p\n", dest->data, child); |
| if (dest->length == 0 && !dest->nonnull) { |
| debug_printf_parse("done_word return 0: true null, ignored\n"); |
| return 0; |
| } |
| if (ctx->pending_redirect) { |
| glob_target = &ctx->pending_redirect->glob_word; |
| } else { |
| if (child->group) { |
| syntax(NULL); |
| debug_printf_parse("done_word return 1: syntax error, groups and arglists don't mix\n"); |
| return 1; |
| } |
| if (!child->argv && (ctx->parse_type & PARSEFLAG_SEMICOLON)) { |
| debug_printf_parse(": checking '%s' for reserved-ness\n", dest->data); |
| if (reserved_word(dest, ctx)) { |
| debug_printf_parse("done_word return %d\n", (ctx->res_w == RES_SNTX)); |
| return (ctx->res_w == RES_SNTX); |
| } |
| } |
| glob_target = &child->argv; |
| } |
| gr = xglob(dest, glob_target); |
| if (gr != 0) { |
| debug_printf_parse("done_word return 1: xglob returned %d\n", gr); |
| return 1; |
| } |
| |
| b_reset(dest); |
| if (ctx->pending_redirect) { |
| /* NB: don't free_strings(ctx->pending_redirect->glob_word) here */ |
| if (ctx->pending_redirect->glob_word |
| && ctx->pending_redirect->glob_word[0] |
| && ctx->pending_redirect->glob_word[1] |
| ) { |
| /* more than one word resulted from globbing redir */ |
| ctx->pending_redirect = NULL; |
| bb_error_msg("ambiguous redirect"); |
| debug_printf_parse("done_word return 1: ambiguous redirect\n"); |
| return 1; |
| } |
| ctx->pending_redirect = NULL; |
| } |
| #if ENABLE_HUSH_LOOPS |
| if (ctx->res_w == RES_FOR) { |
| done_word(dest, ctx); |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| #endif |
| debug_printf_parse("done_word return 0\n"); |
| return 0; |
| } |
| |
| /* The only possible error here is out of memory, in which case |
| * xmalloc exits. */ |
| static int done_command(struct p_context *ctx) |
| { |
| /* The child is really already in the pipe structure, so |
| * advance the pipe counter and make a new, null child. */ |
| struct pipe *pi = ctx->pipe; |
| struct child_prog *child = ctx->child; |
| |
| if (child) { |
| if (child->group == NULL |
| && child->argv == NULL |
| && child->redirects == NULL |
| ) { |
| debug_printf_parse("done_command: skipping null cmd, num_progs=%d\n", pi->num_progs); |
| return pi->num_progs; |
| } |
| pi->num_progs++; |
| debug_printf_parse("done_command: ++num_progs=%d\n", pi->num_progs); |
| } else { |
| debug_printf_parse("done_command: initializing, num_progs=%d\n", pi->num_progs); |
| } |
| |
| /* Only real trickiness here is that the uncommitted |
| * child structure is not counted in pi->num_progs. */ |
| pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1)); |
| child = &pi->progs[pi->num_progs]; |
| |
| memset(child, 0, sizeof(*child)); |
| /*child->redirects = NULL;*/ |
| /*child->argv = NULL;*/ |
| /*child->is_stopped = 0;*/ |
| /*child->group = NULL;*/ |
| child->family = pi; |
| //sp: /*child->sp = 0;*/ |
| //pt: child->parse_type = ctx->parse_type; |
| |
| ctx->child = child; |
| /* but ctx->pipe and ctx->list_head remain unchanged */ |
| |
| return pi->num_progs; /* used only for 0/nonzero check */ |
| } |
| |
| static int done_pipe(struct p_context *ctx, pipe_style type) |
| { |
| struct pipe *new_p; |
| int not_null; |
| |
| debug_printf_parse("done_pipe entered, followup %d\n", type); |
| not_null = done_command(ctx); /* implicit closure of previous command */ |
| ctx->pipe->followup = type; |
| ctx->pipe->res_word = ctx->res_w; |
| /* Without this check, even just <enter> on command line generates |
| * tree of three NOPs (!). Which is harmless but annoying. |
| * IOW: it is safe to do it unconditionally. */ |
| if (not_null) { |
| new_p = new_pipe(); |
| ctx->pipe->next = new_p; |
| ctx->pipe = new_p; |
| ctx->child = NULL; |
| done_command(ctx); /* set up new pipe to accept commands */ |
| } |
| debug_printf_parse("done_pipe return 0\n"); |
| return 0; |
| } |
| |
| /* peek ahead in the in_str to find out if we have a "&n" construct, |
| * as in "2>&1", that represents duplicating a file descriptor. |
| * returns either -2 (syntax error), -1 (no &), or the number found. |
| */ |
| static int redirect_dup_num(struct in_str *input) |
| { |
| int ch, d = 0, ok = 0; |
| ch = b_peek(input); |
| if (ch != '&') return -1; |
| |
| b_getch(input); /* get the & */ |
| ch = b_peek(input); |
| if (ch == '-') { |
| b_getch(input); |
| return -3; /* "-" represents "close me" */ |
| } |
| while (isdigit(ch)) { |
| d = d*10 + (ch-'0'); |
| ok = 1; |
| b_getch(input); |
| ch = b_peek(input); |
| } |
| if (ok) return d; |
| |
| bb_error_msg("ambiguous redirect"); |
| return -2; |
| } |
| |
| /* If a redirect is immediately preceded by a number, that number is |
| * supposed to tell which file descriptor to redirect. This routine |
| * looks for such preceding numbers. In an ideal world this routine |
| * needs to handle all the following classes of redirects... |
| * echo 2>foo # redirects fd 2 to file "foo", nothing passed to echo |
| * echo 49>foo # redirects fd 49 to file "foo", nothing passed to echo |
| * echo -2>foo # redirects fd 1 to file "foo", "-2" passed to echo |
| * echo 49x>foo # redirects fd 1 to file "foo", "49x" passed to echo |
| * A -1 output from this program means no valid number was found, so the |
| * caller should use the appropriate default for this redirection. |
| */ |
| static int redirect_opt_num(o_string *o) |
| { |
| int num; |
| |
| if (o->length == 0) |
| return -1; |
| for (num = 0; num < o->length; num++) { |
| if (!isdigit(*(o->data + num))) { |
| return -1; |
| } |
| } |
| /* reuse num (and save an int) */ |
| num = atoi(o->data); |
| b_reset(o); |
| return num; |
| } |
| |
| #if ENABLE_HUSH_TICK |
| /* NB: currently disabled on NOMMU */ |
| static FILE *generate_stream_from_list(struct pipe *head) |
| { |
| FILE *pf; |
| int pid, channel[2]; |
| |
| xpipe(channel); |
| /* *** NOMMU WARNING *** */ |
| /* By using vfork here, we suspend parent till child exits or execs. |
| * If child will not do it before it fills the pipe, it can block forever |
| * in write(STDOUT_FILENO), and parent (shell) will be also stuck. |
| */ |
| pid = BB_MMU ? fork() : vfork(); |
| if (pid < 0) |
| bb_perror_msg_and_die(BB_MMU ? "fork" : "vfork"); |
| if (pid == 0) { /* child */ |
| if (ENABLE_HUSH_JOB) |
| die_sleep = 0; /* let nofork's xfuncs die */ |
| close(channel[0]); /* NB: close _first_, then move fd! */ |
| xmove_fd(channel[1], 1); |
| /* Prevent it from trying to handle ctrl-z etc */ |
| #if ENABLE_HUSH_JOB |
| run_list_level = 1; |
| #endif |
| /* Process substitution is not considered to be usual |
| * 'command execution'. |
| * SUSv3 says ctrl-Z should be ignored, ctrl-C should not. */ |
| /* Not needed, we are relying on it being disabled |
| * everywhere outside actual command execution. */ |
| /*set_jobctrl_sighandler(SIG_IGN);*/ |
| set_misc_sighandler(SIG_DFL); |
| /* Freeing 'head' here would break NOMMU. */ |
| _exit(run_list(head)); |
| } |
| close(channel[1]); |
| pf = fdopen(channel[0], "r"); |
| return pf; |
| /* 'head' is freed by the caller */ |
| } |
| |
| /* Return code is exit status of the process that is run. */ |
| static int process_command_subs(o_string *dest, struct p_context *ctx, |
| struct in_str *input, const char *subst_end) |
| { |
| int retcode, ch, eol_cnt; |
| o_string result = NULL_O_STRING; |
| struct p_context inner; |
| FILE *p; |
| struct in_str pipe_str; |
| |
| initialize_context(&inner); |
| |
| /* recursion to generate command */ |
| retcode = parse_stream(&result, &inner, input, subst_end); |
| if (retcode != 0) |
| return retcode; /* syntax error or EOF */ |
| done_word(&result, &inner); |
| done_pipe(&inner, PIPE_SEQ); |
| b_free(&result); |
| |
| p = generate_stream_from_list(inner.list_head); |
| if (p == NULL) |
| return 1; |
| close_on_exec_on(fileno(p)); |
| setup_file_in_str(&pipe_str, p); |
| |
| /* now send results of command back into original context */ |
| eol_cnt = 0; |
| while ((ch = b_getch(&pipe_str)) != EOF) { |
| if (ch == '\n') { |
| eol_cnt++; |
| continue; |
| } |
| while (eol_cnt) { |
| b_addqchr(dest, '\n', dest->o_quote); |
| eol_cnt--; |
| } |
| b_addqchr(dest, ch, dest->o_quote); |
| } |
| |
| debug_printf("done reading from pipe, pclose()ing\n"); |
| /* This is the step that wait()s for the child. Should be pretty |
| * safe, since we just read an EOF from its stdout. We could try |
| * to do better, by using wait(), and keeping track of background jobs |
| * at the same time. That would be a lot of work, and contrary |
| * to the KISS philosophy of this program. */ |
| retcode = fclose(p); |
| free_pipe_list(inner.list_head, /* indent: */ 0); |
| debug_printf("closed FILE from child, retcode=%d\n", retcode); |
| return retcode; |
| } |
| #endif |
| |
| static int parse_group(o_string *dest, struct p_context *ctx, |
| struct in_str *input, int ch) |
| { |
| int rcode; |
| const char *endch = NULL; |
| struct p_context sub; |
| struct child_prog *child = ctx->child; |
| |
| debug_printf_parse("parse_group entered\n"); |
| if (child->argv) { |
| syntax(NULL); |
| debug_printf_parse("parse_group return 1: syntax error, groups and arglists don't mix\n"); |
| return 1; |
| } |
| initialize_context(&sub); |
| endch = "}"; |
| if (ch == '(') { |
| endch = ")"; |
| child->subshell = 1; |
| } |
| rcode = parse_stream(dest, &sub, input, endch); |
| //vda: err chk? |
| done_word(dest, &sub); /* finish off the final word in the subcontext */ |
| done_pipe(&sub, PIPE_SEQ); /* and the final command there, too */ |
| child->group = sub.list_head; |
| |
| debug_printf_parse("parse_group return %d\n", rcode); |
| return rcode; |
| /* child remains "open", available for possible redirects */ |
| } |
| |
| /* Basically useful version until someone wants to get fancier, |
| * see the bash man page under "Parameter Expansion" */ |
| static const char *lookup_param(const char *src) |
| { |
| struct variable *var = get_local_var(src); |
| if (var) |
| return strchr(var->varstr, '=') + 1; |
| return NULL; |
| } |
| |
| /* return code: 0 for OK, 1 for syntax error */ |
| static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input) |
| { |
| int ch = b_peek(input); /* first character after the $ */ |
| unsigned char quote_mask = dest->o_quote ? 0x80 : 0; |
| |
| debug_printf_parse("handle_dollar entered: ch='%c'\n", ch); |
| if (isalpha(ch)) { |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| //sp: ctx->child->sp++; |
| while (1) { |
| debug_printf_parse(": '%c'\n", ch); |
| b_getch(input); |
| b_addchr(dest, ch | quote_mask); |
| quote_mask = 0; |
| ch = b_peek(input); |
| if (!isalnum(ch) && ch != '_') |
| break; |
| } |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } else if (isdigit(ch)) { |
| make_one_char_var: |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| //sp: ctx->child->sp++; |
| debug_printf_parse(": '%c'\n", ch); |
| b_getch(input); |
| b_addchr(dest, ch | quote_mask); |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| } else switch (ch) { |
| case '$': /* pid */ |
| case '!': /* last bg pid */ |
| case '?': /* last exit code */ |
| case '#': /* number of args */ |
| case '*': /* args */ |
| case '@': /* args */ |
| goto make_one_char_var; |
| case '{': |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| //sp: ctx->child->sp++; |
| b_getch(input); |
| /* XXX maybe someone will try to escape the '}' */ |
| while (1) { |
| ch = b_getch(input); |
| if (ch == '}') |
| break; |
| if (!isalnum(ch) && ch != '_') { |
| syntax("unterminated ${name}"); |
| debug_printf_parse("handle_dollar return 1: unterminated ${name}\n"); |
| return 1; |
| } |
| debug_printf_parse(": '%c'\n", ch); |
| b_addchr(dest, ch | quote_mask); |
| quote_mask = 0; |
| } |
| b_addchr(dest, SPECIAL_VAR_SYMBOL); |
| break; |
| #if ENABLE_HUSH_TICK |
| case '(': |
| b_getch(input); |
| process_command_subs(dest, ctx, input, ")"); |
| break; |
| #endif |
| case '-': |
| case '_': |
| /* still unhandled, but should be eventually */ |
| bb_error_msg("unhandled syntax: $%c", ch); |
| return 1; |
| break; |
| default: |
| b_addqchr(dest, '$', dest->o_quote); |
| } |
| debug_printf_parse("handle_dollar return 0\n"); |
| return 0; |
| } |
| |
| /* return code is 0 for normal exit, 1 for syntax error */ |
| static int parse_stream(o_string *dest, struct p_context *ctx, |
| struct in_str *input, const char *end_trigger) |
| { |
| int ch, m; |
| int redir_fd; |
| redir_type redir_style; |
| int next; |
| |
| /* Only double-quote state is handled in the state variable dest->o_quote. |
| * A single-quote triggers a bypass of the main loop until its mate is |
| * found. When recursing, quote state is passed in via dest->o_quote. */ |
| |
| debug_printf_parse("parse_stream entered, end_trigger='%s'\n", end_trigger); |
| |
| while (1) { |
| m = CHAR_IFS; |
| next = '\0'; |
| ch = b_getch(input); |
| if (ch != EOF) { |
| m = charmap[ch]; |
| if (ch != '\n') |
| next = b_peek(input); |
| } |
| debug_printf_parse(": ch=%c (%d) m=%d quote=%d\n", |
| ch, ch, m, dest->o_quote); |
| if (m == CHAR_ORDINARY |
| || (m != CHAR_SPECIAL && dest->o_quote) |
| ) { |
| if (ch == EOF) { |
| syntax("unterminated \""); |
| debug_printf_parse("parse_stream return 1: unterminated \"\n"); |
| return 1; |
| } |
| b_addqchr(dest, ch, dest->o_quote); |
| continue; |
| } |
| if (m == CHAR_IFS) { |
| if (done_word(dest, ctx)) { |
| debug_printf_parse("parse_stream return 1: done_word!=0\n"); |
| return 1; |
| } |
| if (ch == EOF) |
| break; |
| /* If we aren't performing a substitution, treat |
| * a newline as a command separator. |
| * [why we don't handle it exactly like ';'? --vda] */ |
| if (end_trigger && ch == '\n') { |
| done_pipe(ctx, PIPE_SEQ); |
| } |
| } |
| if ((end_trigger && strchr(end_trigger, ch)) |
| && !dest->o_quote && ctx->res_w == RES_NONE |
| ) { |
| debug_printf_parse("parse_stream return 0: end_trigger char found\n"); |
| return 0; |
| } |
| if (m == CHAR_IFS) |
| continue; |
| switch (ch) { |
| case '#': |
| if (dest->length == 0 && !dest->o_quote) { |
| while (1) { |
| ch = b_peek(input); |
| if (ch == EOF || ch == '\n') |
| break; |
| b_getch(input); |
| } |
| } else { |
| b_addqchr(dest, ch, dest->o_quote); |
| } |
| break; |
| case '\\': |
| if (next == EOF) { |
| syntax("\\<eof>"); |
| debug_printf_parse("parse_stream return 1: \\<eof>\n"); |
| return 1; |
| } |
| b_addqchr(dest, '\\', dest->o_quote); |
| b_addqchr(dest, b_getch(input), dest->o_quote); |
| break; |
| case '$': |
| if (handle_dollar(dest, ctx, input) != 0) { |
| debug_printf_parse("parse_stream return 1: handle_dollar returned non-0\n"); |
| return 1; |
| } |
| break; |
| case '\'': |
| dest->nonnull = 1; |
| while (1) { |
| ch = b_getch(input); |
| if (ch == EOF || ch == '\'') |
| break; |
| b_addchr(dest, ch); |
| } |
| if (ch == EOF) { |
| syntax("unterminated '"); |
| debug_printf_parse("parse_stream return 1: unterminated '\n"); |
| return 1; |
| } |
| break; |
| case '"': |
| dest->nonnull = 1; |
| dest->o_quote ^= 1; /* invert */ |
| break; |
| #if ENABLE_HUSH_TICK |
| case '`': |
| process_command_subs(dest, ctx, input, "`"); |
| break; |
| #endif |
| case '>': |
| redir_fd = redirect_opt_num(dest); |
| done_word(dest, ctx); |
| redir_style = REDIRECT_OVERWRITE; |
| if (next == '>') { |
| redir_style = REDIRECT_APPEND; |
| b_getch(input); |
| } |
| #if 0 |
| else if (next == '(') { |
| syntax(">(process) not supported"); |
| debug_printf_parse("parse_stream return 1: >(process) not supported\n"); |
| return 1; |
| } |
| #endif |
| setup_redirect(ctx, redir_fd, redir_style, input); |
| break; |
| case '<': |
| redir_fd = redirect_opt_num(dest); |
| done_word(dest, ctx); |
| redir_style = REDIRECT_INPUT; |
| if (next == '<') { |
| redir_style = REDIRECT_HEREIS; |
| b_getch(input); |
| } else if (next == '>') { |
| redir_style = REDIRECT_IO; |
| b_getch(input); |
| } |
| #if 0 |
| else if (next == '(') { |
| syntax("<(process) not supported"); |
| debug_printf_parse("parse_stream return 1: <(process) not supported\n"); |
| return 1; |
| } |
| #endif |
| setup_redirect(ctx, redir_fd, redir_style, input); |
| break; |
| case ';': |
| done_word(dest, ctx); |
| done_pipe(ctx, PIPE_SEQ); |
| break; |
| case '&': |
| done_word(dest, ctx); |
| if (next == '&') { |
| b_getch(input); |
| done_pipe(ctx, PIPE_AND); |
| } else { |
| done_pipe(ctx, PIPE_BG); |
| } |
| break; |
| case '|': |
| done_word(dest, ctx); |
| if (next == '|') { |
| b_getch(input); |
| done_pipe(ctx, PIPE_OR); |
| } else { |
| /* we could pick up a file descriptor choice here |
| * with redirect_opt_num(), but bash doesn't do it. |
| * "echo foo 2| cat" yields "foo 2". */ |
| done_command(ctx); |
| } |
| break; |
| case '(': |
| case '{': |
| if (parse_group(dest, ctx, input, ch) != 0) { |
| debug_printf_parse("parse_stream return 1: parse_group returned non-0\n"); |
| return 1; |
| } |
| break; |
| case ')': |
| case '}': |
| syntax("unexpected }"); /* Proper use of this character is caught by end_trigger */ |
| debug_printf_parse("parse_stream return 1: unexpected '}'\n"); |
| return 1; |
| default: |
| if (ENABLE_HUSH_DEBUG) |
| bb_error_msg_and_die("BUG: unexpected %c\n", ch); |
| } |
| } |
| /* Complain if quote? No, maybe we just finished a command substitution |
| * that was quoted. Example: |
| * $ echo "`cat foo` plus more" |
| * and we just got the EOF generated by the subshell that ran "cat foo" |
| * The only real complaint is if we got an EOF when end_trigger != NULL, |
| * that is, we were really supposed to get end_trigger, and never got |
| * one before the EOF. Can't use the standard "syntax error" return code, |
| * so that parse_stream_outer can distinguish the EOF and exit smoothly. */ |
| debug_printf_parse("parse_stream return %d\n", -(end_trigger != NULL)); |
| if (end_trigger) |
| return -1; |
| return 0; |
| } |
| |
| static void set_in_charmap(const char *set, int code) |
| { |
| while (*set) |
| charmap[(unsigned char)*set++] = code; |
| } |
| |
| static void update_charmap(void) |
| { |
| /* char *ifs and char charmap[256] are both globals. */ |
| ifs = getenv("IFS"); |
| if (ifs == NULL) |
| ifs = " \t\n"; |
| /* Precompute a list of 'flow through' behavior so it can be treated |
| * quickly up front. Computation is necessary because of IFS. |
| * Special case handling of IFS == " \t\n" is not implemented. |
| * The charmap[] array only really needs two bits each, |
| * and on most machines that would be faster (reduced L1 cache use). |
| */ |
| memset(charmap, CHAR_ORDINARY, sizeof(charmap)); |
| #if ENABLE_HUSH_TICK |
| set_in_charmap("\\$\"`", CHAR_SPECIAL); |
| #else |
| set_in_charmap("\\$\"", CHAR_SPECIAL); |
| #endif |
| set_in_charmap("<>;&|(){}#'", CHAR_ORDINARY_IF_QUOTED); |
| set_in_charmap(ifs, CHAR_IFS); /* are ordinary if quoted */ |
| } |
| |
| /* most recursion does not come through here, the exception is |
| * from builtin_source() and builtin_eval() */ |
| static int parse_and_run_stream(struct in_str *inp, int parse_flag) |
| { |
| struct p_context ctx; |
| o_string temp = NULL_O_STRING; |
| int rcode; |
| do { |
| ctx.parse_type = parse_flag; |
| initialize_context(&ctx); |
| update_charmap(); |
| if (!(parse_flag & PARSEFLAG_SEMICOLON) || (parse_flag & PARSEFLAG_REPARSING)) |
| set_in_charmap(";$&|", CHAR_ORDINARY); |
| #if ENABLE_HUSH_INTERACTIVE |
| inp->promptmode = 0; /* PS1 */ |
| #endif |
| /* We will stop & execute after each ';' or '\n'. |
| * Example: "sleep 9999; echo TEST" + ctrl-C: |
| * TEST should be printed */ |
| rcode = parse_stream(&temp, &ctx, inp, ";\n"); |
| if (rcode != 1 && ctx.old_flag != 0) { |
| syntax(NULL); |
| } |
| if (rcode != 1 && ctx.old_flag == 0) { |
| done_word(&temp, &ctx); |
| done_pipe(&ctx, PIPE_SEQ); |
| debug_print_tree(ctx.list_head, 0); |
| debug_printf_exec("parse_stream_outer: run_and_free_list\n"); |
| run_and_free_list(ctx.list_head); |
| } else { |
| if (ctx.old_flag != 0) { |
| free(ctx.stack); |
| b_reset(&temp); |
| } |
| temp.nonnull = 0; |
| temp.o_quote = 0; |
| inp->p = NULL; |
| free_pipe_list(ctx.list_head, /* indent: */ 0); |
| } |
| b_free(&temp); |
| } while (rcode != -1 && !(parse_flag & PARSEFLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */ |
| return 0; |
| } |
| |
| static int parse_and_run_string(const char *s, int parse_flag) |
| { |
| struct in_str input; |
| setup_string_in_str(&input, s); |
| return parse_and_run_stream(&input, parse_flag); |
| } |
| |
| static int parse_and_run_file(FILE *f) |
| { |
| int rcode; |
| struct in_str input; |
| setup_file_in_str(&input, f); |
| rcode = parse_and_run_stream(&input, PARSEFLAG_SEMICOLON); |
| return rcode; |
| } |
| |
| #if ENABLE_HUSH_JOB |
| /* Make sure we have a controlling tty. If we get started under a job |
| * aware app (like bash for example), make sure we are now in charge so |
| * we don't fight over who gets the foreground */ |
| static void setup_job_control(void) |
| { |
| pid_t shell_pgrp; |
| |
| saved_task_pgrp = shell_pgrp = getpgrp(); |
| debug_printf_jobs("saved_task_pgrp=%d\n", saved_task_pgrp); |
| close_on_exec_on(interactive_fd); |
| |
| /* If we were ran as 'hush &', |
| * sleep until we are in the foreground. */ |
| while (tcgetpgrp(interactive_fd) != shell_pgrp) { |
| /* Send TTIN to ourself (should stop us) */ |
| kill(- shell_pgrp, SIGTTIN); |
| shell_pgrp = getpgrp(); |
| } |
| |
| /* Ignore job-control and misc signals. */ |
| set_jobctrl_sighandler(SIG_IGN); |
| set_misc_sighandler(SIG_IGN); |
| //huh? signal(SIGCHLD, SIG_IGN); |
| |
| /* We _must_ restore tty pgrp on fatal signals */ |
| set_fatal_sighandler(sigexit); |
| |
| /* Put ourselves in our own process group. */ |
| setpgrp(); /* is the same as setpgid(our_pid, our_pid); */ |
| /* Grab control of the terminal. */ |
| tcsetpgrp(interactive_fd, getpid()); |
| } |
| #endif |
| |
| int hush_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int hush_main(int argc, char **argv) |
| { |
| static const char version_str[] ALIGN1 = "HUSH_VERSION="HUSH_VER_STR; |
| static const struct variable const_shell_ver = { |
| .next = NULL, |
| .varstr = (char*)version_str, |
| .max_len = 1, /* 0 can provoke free(name) */ |
| .flg_export = 1, |
| .flg_read_only = 1, |
| }; |
| |
| int opt; |
| FILE *input; |
| char **e; |
| struct variable *cur_var; |
| |
| INIT_G(); |
| |
| /* Deal with HUSH_VERSION */ |
| shell_ver = const_shell_ver; /* copying struct here */ |
| top_var = &shell_ver; |
| unsetenv("HUSH_VERSION"); /* in case it exists in initial env */ |
| /* Initialize our shell local variables with the values |
| * currently living in the environment */ |
| cur_var = top_var; |
| e = environ; |
| if (e) while (*e) { |
| char *value = strchr(*e, '='); |
| if (value) { /* paranoia */ |
| cur_var->next = xzalloc(sizeof(*cur_var)); |
| cur_var = cur_var->next; |
| cur_var->varstr = *e; |
| cur_var->max_len = strlen(*e); |
| cur_var->flg_export = 1; |
| } |
| e++; |
| } |
| putenv((char *)version_str); /* reinstate HUSH_VERSION */ |
| |
| #if ENABLE_FEATURE_EDITING |
| line_input_state = new_line_input_t(FOR_SHELL); |
| #endif |
| /* XXX what should these be while sourcing /etc/profile? */ |
| global_argc = argc; |
| global_argv = argv; |
| /* Initialize some more globals to non-zero values */ |
| set_cwd(); |
| #if ENABLE_HUSH_INTERACTIVE |
| #if ENABLE_FEATURE_EDITING |
| cmdedit_set_initial_prompt(); |
| #endif |
| PS2 = "> "; |
| #endif |
| |
| if (EXIT_SUCCESS) /* otherwise is already done */ |
| last_return_code = EXIT_SUCCESS; |
| |
| if (argv[0] && argv[0][0] == '-') { |
| debug_printf("sourcing /etc/profile\n"); |
| input = fopen("/etc/profile", "r"); |
| if (input != NULL) { |
| close_on_exec_on(fileno(input)); |
| parse_and_run_file(input); |
| fclose(input); |
| } |
| } |
| input = stdin; |
| |
| while ((opt = getopt(argc, argv, "c:xif")) > 0) { |
| switch (opt) { |
| case 'c': |
| global_argv = argv + optind; |
| global_argc = argc - optind; |
| opt = parse_and_run_string(optarg, PARSEFLAG_SEMICOLON); |
| goto final_return; |
| case 'i': |
| /* Well, we cannot just declare interactiveness, |
| * we have to have some stuff (ctty, etc) */ |
| /* interactive_fd++; */ |
| break; |
| case 'f': |
| fake_mode = 1; |
| break; |
| default: |
| #ifndef BB_VER |
| fprintf(stderr, "Usage: sh [FILE]...\n" |
| " or: sh -c command [args]...\n\n"); |
| exit(EXIT_FAILURE); |
| #else |
| bb_show_usage(); |
| #endif |
| } |
| } |
| #if ENABLE_HUSH_JOB |
| /* A shell is interactive if the '-i' flag was given, or if all of |
| * the following conditions are met: |
| * no -c command |
| * no arguments remaining or the -s flag given |
| * standard input is a terminal |
| * standard output is a terminal |
| * Refer to Posix.2, the description of the 'sh' utility. */ |
| if (argv[optind] == NULL && input == stdin |
| && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO) |
| ) { |
| saved_tty_pgrp = tcgetpgrp(STDIN_FILENO); |
| debug_printf("saved_tty_pgrp=%d\n", saved_tty_pgrp); |
| if (saved_tty_pgrp >= 0) { |
| /* try to dup to high fd#, >= 255 */ |
| interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255); |
| if (interactive_fd < 0) { |
| /* try to dup to any fd */ |
| interactive_fd = dup(STDIN_FILENO); |
| if (interactive_fd < 0) |
| /* give up */ |
| interactive_fd = 0; |
| } |
| // TODO: track & disallow any attempts of user |
| // to (inadvertently) close/redirect it |
| } |
| } |
| debug_printf("interactive_fd=%d\n", interactive_fd); |
| if (interactive_fd) { |
| fcntl(interactive_fd, F_SETFD, FD_CLOEXEC); |
| /* Looks like they want an interactive shell */ |
| setup_job_control(); |
| /* -1 is special - makes xfuncs longjmp, not exit |
| * (we reset die_sleep = 0 whereever we [v]fork) */ |
| die_sleep = -1; |
| if (setjmp(die_jmp)) { |
| /* xfunc has failed! die die die */ |
| hush_exit(xfunc_error_retval); |
| } |
| #if !ENABLE_FEATURE_SH_EXTRA_QUIET |
| printf("\n\n%s hush - the humble shell v"HUSH_VER_STR"\n", bb_banner); |
| printf("Enter 'help' for a list of built-in commands.\n\n"); |
| #endif |
| } |
| #elif ENABLE_HUSH_INTERACTIVE |
| /* no job control compiled, only prompt/line editing */ |
| if (argv[optind] == NULL && input == stdin |
| && isatty(STDIN_FILENO) && isatty(STDOUT_FILENO) |
| ) { |
| interactive_fd = fcntl(STDIN_FILENO, F_DUPFD, 255); |
| if (interactive_fd < 0) { |
| /* try to dup to any fd */ |
| interactive_fd = dup(STDIN_FILENO); |
| if (interactive_fd < 0) |
| /* give up */ |
| interactive_fd = 0; |
| } |
| if (interactive_fd) |
| fcntl(interactive_fd, F_SETFD, FD_CLOEXEC); |
| } |
| #endif |
| |
| if (argv[optind] == NULL) { |
| opt = parse_and_run_file(stdin); |
| } else { |
| debug_printf("\nrunning script '%s'\n", argv[optind]); |
| global_argv = argv + optind; |
| global_argc = argc - optind; |
| input = xfopen(argv[optind], "r"); |
| fcntl(fileno(input), F_SETFD, FD_CLOEXEC); |
| opt = parse_and_run_file(input); |
| } |
| |
| final_return: |
| |
| #if ENABLE_FEATURE_CLEAN_UP |
| fclose(input); |
| if (cwd != bb_msg_unknown) |
| free((char*)cwd); |
| cur_var = top_var->next; |
| while (cur_var) { |
| struct variable *tmp = cur_var; |
| if (!cur_var->max_len) |
| free(cur_var->varstr); |
| cur_var = cur_var->next; |
| free(tmp); |
| } |
| #endif |
| hush_exit(opt ? opt : last_return_code); |
| } |
| |
| |
| #if ENABLE_LASH |
| int lash_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; |
| int lash_main(int argc, char **argv) |
| { |
| //bb_error_msg("lash is deprecated, please use hush instead"); |
| return hush_main(argc, argv); |
| } |
| #endif |