| /* 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) 2000 by Lineo, Inc., and |
| * written by Erik Andersen <andersen@lineo.com>, <andersee@debian.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: |
| * simple_itoa() was lifted from boa-0.93.15 |
| * 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?) |
| * $@ (those sure look like weird quoting rules) |
| * $_ |
| * ! 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 |
| * 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 |
| * finish implementing local variable assignment |
| * 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 map[] to use 2-bit entries |
| * (eventually) remove all the printf's |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * This program is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA |
| */ |
| #include <ctype.h> /* isalpha, isdigit */ |
| #include <unistd.h> /* getpid */ |
| #include <stdlib.h> /* getenv, atoi */ |
| #include <string.h> /* strchr */ |
| #include <stdio.h> /* popen etc. */ |
| #include <glob.h> /* glob, of course */ |
| #include <stdarg.h> /* va_list */ |
| #include <errno.h> |
| #include <fcntl.h> |
| #include <getopt.h> /* should be pretty obvious */ |
| |
| #include <sys/stat.h> /* ulimit */ |
| #include <sys/types.h> |
| #include <sys/wait.h> |
| #include <signal.h> |
| |
| /* #include <dmalloc.h> */ |
| /* #define DEBUG_SHELL */ |
| |
| #ifdef BB_VER |
| #include "busybox.h" |
| #include "cmdedit.h" |
| #else |
| #define applet_name "hush" |
| #include "standalone.h" |
| #define shell_main main |
| #define BB_FEATURE_SH_SIMPLE_PROMPT |
| #endif |
| |
| 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 */ |
| struct {int mode; int default_fd; char *descrip;} 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, |
| RES_IF = 1, |
| RES_THEN = 2, |
| RES_ELIF = 3, |
| RES_ELSE = 4, |
| RES_FI = 5, |
| RES_FOR = 6, |
| RES_WHILE = 7, |
| RES_UNTIL = 8, |
| RES_DO = 9, |
| RES_DONE = 10, |
| RES_XXXX = 11, |
| RES_SNTX = 12 |
| } reserved_style; |
| #define FLAG_END (1<<RES_NONE) |
| #define FLAG_IF (1<<RES_IF) |
| #define FLAG_THEN (1<<RES_THEN) |
| #define FLAG_ELIF (1<<RES_ELIF) |
| #define FLAG_ELSE (1<<RES_ELSE) |
| #define FLAG_FI (1<<RES_FI) |
| #define FLAG_FOR (1<<RES_FOR) |
| #define FLAG_WHILE (1<<RES_WHILE) |
| #define FLAG_UNTIL (1<<RES_UNTIL) |
| #define FLAG_DO (1<<RES_DO) |
| #define FLAG_DONE (1<<RES_DONE) |
| #define 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; |
| reserved_style w; |
| int old_flag; /* for figuring out valid reserved words */ |
| struct p_context *stack; |
| /* How about quoting status? */ |
| }; |
| |
| struct redir_struct { |
| redir_type type; /* type of redirection */ |
| int fd; /* file descriptor being redirected */ |
| int dup; /* -1, or file descriptor being duplicated */ |
| struct redir_struct *next; /* pointer to the next redirect in the list */ |
| glob_t 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 */ |
| int subshell; /* flag, non-zero if group must be forked */ |
| struct redir_struct *redirects; /* I/O redirections */ |
| glob_t glob_result; /* result of parameter globbing */ |
| int is_stopped; /* is the program currently running? */ |
| struct pipe *family; /* pointer back to the child's parent pipe */ |
| }; |
| |
| struct pipe { |
| int jobid; /* job number */ |
| int num_progs; /* total number of programs in job */ |
| int running_progs; /* number of programs running */ |
| char *text; /* name of job */ |
| char *cmdbuf; /* buffer various argv's point into */ |
| pid_t pgrp; /* process group ID for the job */ |
| struct child_prog *progs; /* array of commands in pipe */ |
| struct pipe *next; /* to track background commands */ |
| int stopped_progs; /* number of programs alive, but stopped */ |
| int job_context; /* bitmask defining current context */ |
| pipe_style followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ |
| reserved_style r_mode; /* supports if, for, while, until */ |
| }; |
| |
| struct jobset { |
| struct pipe *head; /* head of list of running jobs */ |
| struct pipe *fg; /* current foreground job */ |
| }; |
| |
| struct close_me { |
| int fd; |
| struct close_me *next; |
| }; |
| |
| /* globals, connect us to the outside world |
| * the first three support $?, $#, and $1 */ |
| char **global_argv; |
| unsigned int global_argc; |
| unsigned int last_return_code; |
| extern char **environ; /* This is in <unistd.h>, but protected with __USE_GNU */ |
| |
| /* Variables we export */ |
| unsigned int shell_context; /* Used in cmdedit.c to reset the |
| * context when someone hits ^C */ |
| |
| /* "globals" within this file */ |
| static char *ifs=NULL; |
| static char map[256]; |
| static int fake_mode=0; |
| static int interactive=0; |
| static struct close_me *close_me_head = NULL; |
| static const char *cwd; |
| static struct jobset *job_list; |
| static unsigned int last_bg_pid=0; |
| static char *PS1; |
| static char *PS2 = "> "; |
| |
| #define B_CHUNK (100) |
| #define B_NOSPAC 1 |
| #define MAX_LINE 256 /* for cwd */ |
| #define MAX_READ 256 /* for builtin_read */ |
| |
| typedef struct { |
| char *data; |
| int length; |
| int maxlen; |
| int quote; |
| int 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; |
| int __promptme; |
| int promptmode; |
| 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)) |
| |
| #define JOB_STATUS_FORMAT "[%d] %-22s %.40s\n" |
| |
| struct built_in_command { |
| char *cmd; /* name */ |
| char *descr; /* description */ |
| int (*function) (struct child_prog *); /* function ptr */ |
| }; |
| |
| /* belongs in busybox.h */ |
| static inline int max(int a, int b) { |
| return (a>b)?a:b; |
| } |
| |
| /* This should be in utility.c */ |
| #ifdef DEBUG_SHELL |
| static void debug_printf(const char *format, ...) |
| { |
| va_list args; |
| va_start(args, format); |
| vfprintf(stderr, format, args); |
| va_end(args); |
| } |
| #else |
| static void debug_printf(const char *format, ...) { } |
| #endif |
| #define final_printf debug_printf |
| |
| void __syntax(char *file, int line) { |
| fprintf(stderr,"syntax error %s:%d\n",file,line); |
| } |
| #define syntax() __syntax(__FILE__, __LINE__) |
| |
| /* Index of subroutines: */ |
| /* function prototypes for builtins */ |
| static int builtin_cd(struct child_prog *child); |
| static int builtin_env(struct child_prog *child); |
| static int builtin_exec(struct child_prog *child); |
| static int builtin_exit(struct child_prog *child); |
| static int builtin_export(struct child_prog *child); |
| static int builtin_fg_bg(struct child_prog *child); |
| static int builtin_help(struct child_prog *child); |
| static int builtin_jobs(struct child_prog *child); |
| static int builtin_pwd(struct child_prog *child); |
| static int builtin_read(struct child_prog *child); |
| static int builtin_shift(struct child_prog *child); |
| static int builtin_source(struct child_prog *child); |
| static int builtin_umask(struct child_prog *child); |
| static int builtin_unset(struct child_prog *child); |
| static int builtin_not_written(struct child_prog *child); |
| /* 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); |
| static int b_adduint(o_string *o, unsigned int i); |
| /* 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); |
| /* close_me manipulations: */ |
| static void mark_open(int fd); |
| static void mark_closed(int fd); |
| static void close_all(); |
| /* "run" the final data structures: */ |
| static char *indenter(int i); |
| static int run_list_test(struct pipe *head, int indent); |
| static int run_pipe_test(struct pipe *pi, int indent); |
| /* really run the final data structures: */ |
| static int setup_redirects(struct child_prog *prog, int squirrel[]); |
| static int pipe_wait(struct pipe *pi); |
| static int run_list_real(struct pipe *pi); |
| static void pseudo_exec(struct child_prog *child) __attribute__ ((noreturn)); |
| static int run_pipe_real(struct pipe *pi); |
| /* extended glob support: */ |
| static int globhack(const char *src, int flags, glob_t *pglob); |
| static int glob_needed(const char *s); |
| static int xglob(o_string *dest, int flags, glob_t *pglob); |
| /* variable assignment: */ |
| static int set_local_var(const char *s); |
| 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); |
| static int process_command_subs(o_string *dest, struct p_context *ctx, struct in_str *input, int subst_end); |
| static int parse_group(o_string *dest, struct p_context *ctx, struct in_str *input, int ch); |
| static void lookup_param(o_string *dest, struct p_context *ctx, o_string *src); |
| static int handle_dollar(o_string *dest, struct p_context *ctx, struct in_str *input); |
| static int parse_string(o_string *dest, struct p_context *ctx, const char *src); |
| static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, int end_trigger); |
| /* setup: */ |
| static int parse_stream_outer(struct in_str *inp); |
| static int parse_string_outer(const char *s); |
| static int parse_file_outer(FILE *f); |
| /* job management: */ |
| static void checkjobs(); |
| static void insert_bg_job(struct pipe *pi); |
| static void remove_bg_job(struct pipe *pi); |
| static void free_pipe(struct pipe *pi); |
| |
| /* 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 can not. |
| * For example, 'unset foo | whatever' will parse and run, but foo will |
| * still be set at the end. */ |
| static struct built_in_command bltins[] = { |
| {"bg", "Resume a job in the background", builtin_fg_bg}, |
| {"break", "Exit for, while or until loop", builtin_not_written}, |
| {"cd", "Change working directory", builtin_cd}, |
| {"continue", "Continue for, while or until loop", builtin_not_written}, |
| {"env", "Print all environment variables", builtin_env}, |
| {"eval", "Construct and run shell command", builtin_not_written}, |
| {"exec", "Exec command, replacing this shell with the exec'd process", builtin_exec}, |
| {"exit", "Exit from shell()", builtin_exit}, |
| {"export", "Set environment variable", builtin_export}, |
| {"fg", "Bring job into the foreground", builtin_fg_bg}, |
| {"jobs", "Lists the active jobs", builtin_jobs}, |
| {"pwd", "Print current directory", builtin_pwd}, |
| {"read", "Input environment variable", builtin_read}, |
| {"return", "Return from a function", builtin_not_written}, |
| {"set", "Set/unset shell options", builtin_not_written}, |
| {"shift", "Shift positional parameters", builtin_shift}, |
| {"trap", "Trap signals", builtin_not_written}, |
| {"ulimit","Controls resource limits", builtin_not_written}, |
| {"umask","Sets file creation mask", builtin_umask}, |
| {"unset", "Unset environment variable", builtin_unset}, |
| {".", "Source-in and run commands in a file", builtin_source}, |
| {"help", "List shell built-in commands", builtin_help}, |
| {NULL, NULL, NULL} |
| }; |
| |
| /* built-in 'cd <path>' handler */ |
| static int builtin_cd(struct child_prog *child) |
| { |
| char *newdir; |
| if (child->argv[1] == NULL) |
| newdir = getenv("HOME"); |
| else |
| newdir = child->argv[1]; |
| if (chdir(newdir)) { |
| printf("cd: %s: %s\n", newdir, strerror(errno)); |
| return EXIT_FAILURE; |
| } |
| cwd = xgetcwd((char *)cwd); |
| if (!cwd) |
| cwd = unknown; |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'env' handler */ |
| static int builtin_env(struct child_prog *dummy) |
| { |
| char **e = environ; |
| if (e == NULL) return EXIT_FAILURE; |
| for (; *e; e++) { |
| puts(*e); |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'exec' handler */ |
| static int builtin_exec(struct child_prog *child) |
| { |
| if (child->argv[1] == NULL) |
| return EXIT_SUCCESS; /* Really? */ |
| child->argv++; |
| pseudo_exec(child); |
| /* never returns */ |
| } |
| |
| /* built-in 'exit' handler */ |
| static int builtin_exit(struct child_prog *child) |
| { |
| if (child->argv[1] == NULL) |
| exit(last_return_code); |
| exit (atoi(child->argv[1])); |
| } |
| |
| /* built-in 'export VAR=value' handler */ |
| static int builtin_export(struct child_prog *child) |
| { |
| int res; |
| |
| if (child->argv[1] == NULL) { |
| return (builtin_env(child)); |
| } |
| /* FIXME -- I leak memory. This will be |
| * fixed up properly when we add local |
| * variable support -- I hope */ |
| res = putenv(strdup(child->argv[1])); |
| if (res) |
| fprintf(stderr, "export: %s\n", strerror(errno)); |
| return (res); |
| } |
| |
| /* built-in 'fg' and 'bg' handler */ |
| static int builtin_fg_bg(struct child_prog *child) |
| { |
| int i, jobnum; |
| struct pipe *pi=NULL; |
| |
| /* If they gave us no args, assume they want the last backgrounded task */ |
| if (!child->argv[1]) { |
| for (pi = job_list->head; pi; pi = pi->next) { |
| if (pi->progs && pi->progs->pid == last_bg_pid) { |
| break; |
| } |
| } |
| if (!pi) { |
| error_msg("%s: no current job", child->argv[0]); |
| return EXIT_FAILURE; |
| } |
| } else { |
| if (sscanf(child->argv[1], "%%%d", &jobnum) != 1) { |
| error_msg("%s: bad argument '%s'", child->argv[0], child->argv[1]); |
| return EXIT_FAILURE; |
| } |
| |
| for (pi = job_list->head; pi; pi = pi->next) { |
| if (pi->jobid == jobnum) { |
| break; |
| } |
| } |
| if (!pi) { |
| error_msg("%s: %d: no such job", child->argv[0], jobnum); |
| return EXIT_FAILURE; |
| } |
| } |
| if (*child->argv[0] == 'f') { |
| /* Make this job the foreground job */ |
| signal(SIGTTOU, SIG_IGN); |
| /* suppress messages when run from /linuxrc mag@sysgo.de */ |
| if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY) |
| perror_msg("tcsetpgrp"); |
| signal(SIGTTOU, SIG_DFL); |
| job_list->fg = pi; |
| } |
| |
| /* Restart the processes in the job */ |
| for (i = 0; i < pi->num_progs; i++) |
| pi->progs[i].is_stopped = 0; |
| |
| kill(-pi->pgrp, SIGCONT); |
| |
| pi->stopped_progs = 0; |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'help' handler */ |
| static int builtin_help(struct child_prog *dummy) |
| { |
| struct built_in_command *x; |
| |
| printf("\nBuilt-in commands:\n"); |
| printf("-------------------\n"); |
| for (x = bltins; x->cmd; x++) { |
| if (x->descr==NULL) |
| continue; |
| printf("%s\t%s\n", x->cmd, x->descr); |
| } |
| printf("\n\n"); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'jobs' handler */ |
| static int builtin_jobs(struct child_prog *child) |
| { |
| struct pipe *job; |
| char *status_string; |
| |
| for (job = job_list->head; 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->text); |
| } |
| return EXIT_SUCCESS; |
| } |
| |
| |
| /* built-in 'pwd' handler */ |
| static int builtin_pwd(struct child_prog *dummy) |
| { |
| cwd = xgetcwd((char *)cwd); |
| if (!cwd) |
| cwd = unknown; |
| puts(cwd); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'read VAR' handler */ |
| static int builtin_read(struct child_prog *child) |
| { |
| int res = 0, len, newlen; |
| char *s; |
| char string[MAX_READ]; |
| |
| if (child->argv[1]) { |
| /* argument (VAR) given: put "VAR=" into buffer */ |
| strcpy(string, child->argv[1]); |
| len = strlen(string); |
| string[len++] = '='; |
| string[len] = '\0'; |
| /* XXX would it be better to go through in_str? */ |
| fgets(&string[len], sizeof(string) - len, stdin); /* read string */ |
| newlen = strlen(string); |
| if(newlen > len) |
| string[--newlen] = '\0'; /* chomp trailing newline */ |
| /* |
| ** string should now contain "VAR=<value>" |
| ** copy it (putenv() won't do that, so we must make sure |
| ** the string resides in a static buffer!) |
| */ |
| res = -1; |
| if((s = strdup(string))) |
| res = putenv(s); |
| if (res) |
| fprintf(stderr, "read: %s\n", strerror(errno)); |
| } |
| else |
| fgets(string, sizeof(string), stdin); |
| |
| return (res); |
| } |
| |
| /* Built-in 'shift' handler */ |
| static int builtin_shift(struct child_prog *child) |
| { |
| int n=1; |
| if (child->argv[1]) { |
| n=atoi(child->argv[1]); |
| } |
| if (n>=0 && n<global_argc) { |
| /* XXX This probably breaks $0 */ |
| global_argc -= n; |
| global_argv += n; |
| return EXIT_SUCCESS; |
| } else { |
| return EXIT_FAILURE; |
| } |
| } |
| |
| /* Built-in '.' handler (read-in and execute commands from file) */ |
| static int builtin_source(struct child_prog *child) |
| { |
| FILE *input; |
| int status; |
| |
| if (child->argv[1] == NULL) |
| return EXIT_FAILURE; |
| |
| /* XXX search through $PATH is missing */ |
| input = fopen(child->argv[1], "r"); |
| if (!input) { |
| fprintf(stderr, "Couldn't open file '%s'\n", child->argv[1]); |
| return EXIT_FAILURE; |
| } |
| |
| /* 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=child->argv+1, recurse, and restore. */ |
| mark_open(fileno(input)); |
| status = parse_file_outer(input); |
| mark_closed(fileno(input)); |
| fclose(input); |
| return (status); |
| } |
| |
| static int builtin_umask(struct child_prog *child) |
| { |
| mode_t new_umask; |
| const char *arg = child->argv[1]; |
| char *end; |
| if (arg) { |
| new_umask=strtoul(arg, &end, 8); |
| if (*end!='\0' || end == arg) { |
| return EXIT_FAILURE; |
| } |
| } else { |
| printf("%.3o\n", (unsigned int) (new_umask=umask(0))); |
| } |
| umask(new_umask); |
| return EXIT_SUCCESS; |
| } |
| |
| /* built-in 'unset VAR' handler */ |
| static int builtin_unset(struct child_prog *child) |
| { |
| if (child->argv[1] == NULL) { |
| fprintf(stderr, "unset: parameter required.\n"); |
| return EXIT_FAILURE; |
| } |
| unsetenv(child->argv[1]); |
| return EXIT_SUCCESS; |
| } |
| |
| static int builtin_not_written(struct child_prog *child) |
| { |
| printf("builtin_%s not written\n",child->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) { |
| char *old_data = o->data; |
| /* assert (data == NULL || o->maxlen != 0); */ |
| o->maxlen += max(2*len, B_CHUNK); |
| o->data = realloc(o->data, 1 + o->maxlen); |
| if (o->data == NULL) { |
| free(old_data); |
| } |
| } |
| return o->data == NULL; |
| } |
| |
| static int b_addchr(o_string *o, int ch) |
| { |
| debug_printf("b_addchr: %c %d %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 != NULL) *o->data = '\0'; |
| } |
| |
| static void b_free(o_string *o) |
| { |
| b_reset(o); |
| if (o->data != NULL) free(o->data); |
| o->data = NULL; |
| o->maxlen = 0; |
| } |
| |
| /* 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); |
| } |
| |
| /* belongs in utility.c */ |
| char *simple_itoa(unsigned int i) |
| { |
| /* 21 digits plus null terminator, good for 64-bit or smaller ints */ |
| static char local[22]; |
| char *p = &local[21]; |
| *p-- = '\0'; |
| do { |
| *p-- = '0' + i % 10; |
| i /= 10; |
| } while (i > 0); |
| return p + 1; |
| } |
| |
| static int b_adduint(o_string *o, unsigned int i) |
| { |
| int r; |
| char *p = simple_itoa(i); |
| /* no escape checking necessary */ |
| do r=b_addchr(o, *p++); while (r==0 && *p); |
| return r; |
| } |
| |
| 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; |
| } |
| |
| static inline void cmdedit_set_initial_prompt(void) |
| { |
| #ifdef BB_FEATURE_SH_SIMPLE_PROMPT |
| PS1 = NULL; |
| #else |
| PS1 = getenv("PS1"); |
| if(PS1==0) |
| PS1 = "\\w \\$ "; |
| #endif |
| } |
| |
| static inline void setup_prompt_string(int promptmode, char **prompt_str) |
| { |
| debug_printf("setup_prompt_string %d ",promptmode); |
| #ifdef BB_FEATURE_SH_SIMPLE_PROMPT |
| /* Set up the prompt */ |
| if (promptmode == 1) { |
| if (PS1) |
| free(PS1); |
| PS1=xmalloc(strlen(cwd)+4); |
| sprintf(PS1, "%s %s", 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); |
| } |
| |
| static void get_user_input(struct in_str *i) |
| { |
| char *prompt_str; |
| static char the_command[BUFSIZ]; |
| |
| setup_prompt_string(i->promptmode, &prompt_str); |
| #ifdef BB_FEATURE_COMMAND_EDITING |
| /* |
| ** enable command line editing only while a command line |
| ** is actually being read; otherwise, we'll end up bequeathing |
| ** atexit() handlers and other unwanted stuff to our |
| ** child processes (rob@sysgo.de) |
| */ |
| cmdedit_read_input(prompt_str, the_command); |
| cmdedit_terminate(); |
| #else |
| fputs(prompt_str, stdout); |
| fflush(stdout); |
| the_command[0]=fgetc(i->file); |
| the_command[1]='\0'; |
| #endif |
| i->p = the_command; |
| } |
| |
| /* 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; |
| |
| ch = 0; |
| /* If there is data waiting, eat it up */ |
| if (i->p && *i->p) { |
| ch=*i->p++; |
| } else { |
| /* need to double check i->file because we might be doing something |
| * more complicated by now, like sourcing or substituting. */ |
| if (i->__promptme && interactive && i->file == stdin) { |
| get_user_input(i); |
| i->promptmode=2; |
| i->__promptme = 0; |
| if (i->p && *i->p) { |
| ch=*i->p++; |
| } |
| } else { |
| ch = fgetc(i->file); |
| } |
| |
| debug_printf("b_getch: got a %d\n", ch); |
| } |
| if (ch == '\n') i->__promptme=1; |
| 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) |
| { |
| if (i->p && *i->p) { |
| return *i->p; |
| } else { |
| static char buffer[2]; |
| buffer[0] = fgetc(i->file); |
| buffer[1] = '\0'; |
| i->p = buffer; |
| debug_printf("b_peek: got a %d\n", *i->p); |
| return *i->p; |
| } |
| } |
| |
| static void setup_file_in_str(struct in_str *i, FILE *f) |
| { |
| i->peek = file_peek; |
| i->get = file_get; |
| i->__promptme=1; |
| i->promptmode=1; |
| 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; |
| i->__promptme=1; |
| i->promptmode=1; |
| i->p = s; |
| } |
| |
| static void mark_open(int fd) |
| { |
| struct close_me *new = xmalloc(sizeof(struct close_me)); |
| new->fd = fd; |
| new->next = close_me_head; |
| close_me_head = new; |
| } |
| |
| static void mark_closed(int fd) |
| { |
| struct close_me *tmp; |
| if (close_me_head == NULL || close_me_head->fd != fd) |
| error_msg_and_die("corrupt close_me"); |
| tmp = close_me_head; |
| close_me_head = close_me_head->next; |
| free(tmp); |
| } |
| |
| static void close_all() |
| { |
| struct close_me *c; |
| for (c=close_me_head; c; c=c->next) { |
| close(c->fd); |
| } |
| close_me_head = NULL; |
| } |
| |
| /* 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) { |
| mode=redir_table[redir->type].mode; |
| openfd = open(redir->word.gl_pathv[0], mode, 0666); |
| 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!) */ |
| fprintf(stderr,"error opening %s: %s\n", redir->word.gl_pathv[0], |
| strerror(errno)); |
| 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); |
| } else { |
| dup2(openfd, redir->fd); |
| 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) { |
| /* No error checking. I sure wouldn't know what |
| * to do with an error if I found one! */ |
| dup2(fd, i); |
| close(fd); |
| } |
| } |
| } |
| |
| /* XXX this definitely needs some more thought, work, and |
| * cribbing from other shells */ |
| static int pipe_wait(struct pipe *pi) |
| { |
| int rcode=0, i, pid, running, status; |
| running = pi->num_progs; |
| while (running) { |
| pid=waitpid(-1, &status, 0); |
| if (pid < 0) perror_msg_and_die("waitpid"); |
| for (i=0; i < pi->num_progs; i++) { |
| if (pi->progs[i].pid == pid) { |
| if (i==pi->num_progs-1) rcode=WEXITSTATUS(status); |
| pi->progs[i].pid = 0; |
| running--; |
| break; |
| } |
| } |
| } |
| return rcode; |
| } |
| |
| /* very simple version for testing */ |
| static void pseudo_exec(struct child_prog *child) |
| { |
| int i, rcode; |
| struct built_in_command *x; |
| if (child->argv) { |
| for (i=0; is_assignment(child->argv[i]); i++) { |
| putenv(strdup(child->argv[i])); |
| } |
| child->argv+=i; /* XXX this hack isn't so horrible, since we are about |
| to exit, and therefore don't need to keep data |
| structures consistent for free() use. */ |
| /* If a variable is assigned in a forest, and nobody listens, |
| * was it ever really set? |
| */ |
| if (child->argv[0] == NULL) exit(EXIT_SUCCESS); |
| |
| /* |
| * 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(child->argv[0], x->cmd) == 0 ) { |
| debug_printf("builtin exec %s\n", child->argv[0]); |
| exit(x->function(child)); |
| } |
| } |
| |
| /* Check if the command matches any busybox internal commands |
| * ("applets") here. |
| * FIXME: This feature is not 100% safe, since |
| * BusyBox is not fully reentrant, so we have no guarantee the things |
| * from the .bss are still zeroed, or that things from .data are still |
| * at their defaults. We could exec ourself from /proc/self/exe, but I |
| * really dislike relying on /proc for things. We could exec ourself |
| * from global_argv[0], but if we are in a chroot, we may not be able |
| * to find ourself... */ |
| #ifdef BB_FEATURE_SH_STANDALONE_SHELL |
| { |
| int argc_l; |
| char** argv_l=child->argv; |
| char *name = child->argv[0]; |
| |
| #ifdef BB_FEATURE_SH_APPLETS_ALWAYS_WIN |
| /* Following discussions from November 2000 on the busybox mailing |
| * list, the default configuration, (without |
| * get_last_path_component()) lets the user force use of an |
| * external command by specifying the full (with slashes) filename. |
| * If you enable BB_FEATURE_SH_APPLETS_ALWAYS_WIN, then applets |
| * _aways_ override external commands, so if you want to run |
| * /bin/cat, it will use BusyBox cat even if /bin/cat exists on the |
| * filesystem and is _not_ busybox. Some systems may want this, |
| * most do not. */ |
| name = get_last_path_component(name); |
| #endif |
| /* Count argc for use in a second... */ |
| for(argc_l=0;*argv_l!=NULL; argv_l++, argc_l++); |
| optind = 1; |
| debug_printf("running applet %s\n", name); |
| run_applet_by_name(name, argc_l, child->argv); |
| } |
| #endif |
| debug_printf("exec of %s\n",child->argv[0]); |
| execvp(child->argv[0],child->argv); |
| perror("execvp"); |
| exit(1); |
| } else if (child->group) { |
| debug_printf("runtime nesting to group\n"); |
| interactive=0; /* crucial!!!! */ |
| rcode = run_list_real(child->group); |
| /* OK to leak memory by not calling run_list_test, |
| * since this process is about to exit */ |
| exit(rcode); |
| } else { |
| /* Can happen. See what bash does with ">foo" by itself. */ |
| debug_printf("trying to pseudo_exec null command\n"); |
| exit(EXIT_SUCCESS); |
| } |
| } |
| |
| static void insert_bg_job(struct pipe *pi) |
| { |
| struct pipe *thejob; |
| |
| /* Linear search for the ID of the job to use */ |
| pi->jobid = 1; |
| for (thejob = job_list->head; 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->head) { |
| thejob = job_list->head = xmalloc(sizeof(*thejob)); |
| } else { |
| for (thejob = job_list->head; thejob->next; thejob = thejob->next) /* nothing */; |
| thejob->next = xmalloc(sizeof(*thejob)); |
| thejob = thejob->next; |
| } |
| |
| /* physically copy the struct job */ |
| memcpy(thejob, pi, sizeof(struct pipe)); |
| thejob->next = NULL; |
| thejob->running_progs = thejob->num_progs; |
| thejob->stopped_progs = 0; |
| thejob->text = xmalloc(MAX_LINE); |
| |
| //if (pi->progs[0] && pi->progs[0].argv && pi->progs[0].argv[0]) |
| { |
| char *bar=thejob->text; |
| char **foo=pi->progs[0].argv; |
| while(foo && *foo) { |
| bar += sprintf(bar, "%s ", *foo++); |
| } |
| } |
| |
| /* we don't wait for background thejobs to return -- append it |
| to the list of backgrounded thejobs and leave it alone */ |
| printf("[%d] %d\n", thejob->jobid, thejob->progs[0].pid); |
| last_bg_pid = thejob->progs[0].pid; |
| } |
| |
| /* remove a backgrounded job from a jobset */ |
| static void remove_bg_job(struct pipe *pi) |
| { |
| struct pipe *prev_pipe; |
| |
| free_pipe(pi); |
| if (pi == job_list->head) { |
| job_list->head = pi->next; |
| } else { |
| prev_pipe = job_list->head; |
| while (prev_pipe->next != pi) |
| prev_pipe = prev_pipe->next; |
| prev_pipe->next = pi->next; |
| } |
| |
| free(pi); |
| } |
| |
| /* free up all memory from a pipe */ |
| static void free_pipe(struct pipe *pi) |
| { |
| int i; |
| |
| for (i = 0; i < pi->num_progs; i++) { |
| free(pi->progs[i].argv); |
| if (pi->progs[i].redirects) |
| free(pi->progs[i].redirects); |
| } |
| if (pi->progs) |
| free(pi->progs); |
| if (pi->text) |
| free(pi->text); |
| if (pi->cmdbuf) |
| free(pi->cmdbuf); |
| memset(pi, 0, sizeof(struct pipe)); |
| } |
| |
| |
| /* Checks to see if any background processes have exited -- if they |
| have, figure out why and see if a job has completed */ |
| static void checkjobs() |
| { |
| int status; |
| int prognum = 0; |
| struct pipe *pi; |
| pid_t childpid; |
| |
| while ((childpid = waitpid(-1, &status, WNOHANG | WUNTRACED)) > 0) { |
| for (pi = job_list->head; pi; pi = pi->next) { |
| prognum = 0; |
| while (prognum < pi->num_progs && |
| pi->progs[prognum].pid != childpid) prognum++; |
| if (prognum < pi->num_progs) |
| break; |
| } |
| |
| if (WIFEXITED(status) || WIFSIGNALED(status)) { |
| /* child exited */ |
| pi->running_progs--; |
| pi->progs[prognum].pid = 0; |
| |
| if (!pi->running_progs) { |
| printf(JOB_STATUS_FORMAT, pi->jobid, "Done", pi->text); |
| remove_bg_job(pi); |
| } |
| } else { |
| if(pi==NULL) |
| break; |
| /* child stopped */ |
| pi->stopped_progs++; |
| pi->progs[prognum].is_stopped = 1; |
| |
| if (pi->stopped_progs == pi->num_progs) { |
| printf(JOB_STATUS_FORMAT, pi->jobid, "Stopped", pi->text); |
| } |
| } |
| } |
| |
| if (childpid == -1 && errno != ECHILD) |
| perror_msg("waitpid"); |
| |
| /* move the shell to the foreground */ |
| if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY) |
| perror_msg("tcsetpgrp"); |
| } |
| |
| /* run_pipe_real() starts all the jobs, but doesn't wait for anything |
| * to finish. See pipe_wait(). |
| * |
| * 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_real 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. |
| */ |
| static int run_pipe_real(struct pipe *pi) |
| { |
| int i; |
| int ctty; |
| int nextin, nextout; |
| int pipefds[2]; /* pipefds[0] is for reading */ |
| struct child_prog *child; |
| struct built_in_command *x; |
| |
| ctty = -1; |
| nextin = 0; |
| pi->pgrp = 0; |
| |
| /* Check if we are supposed to run in the foreground */ |
| if (interactive && pi->followup!=PIPE_BG) { |
| if ((pi->pgrp = tcgetpgrp(ctty = 2)) < 0 |
| && (pi->pgrp = tcgetpgrp(ctty = 0)) < 0 |
| && (pi->pgrp = tcgetpgrp(ctty = 1)) < 0) |
| return errno = ENOTTY, -1; |
| |
| if (pi->pgrp < 0 && pi->pgrp != getpgrp()) |
| return errno = EPERM, -1; |
| } |
| |
| /* 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. |
| */ |
| if (pi->num_progs == 1 && pi->progs[0].argv != NULL) { |
| child = & (pi->progs[0]); |
| if (child->group && ! child->subshell) { |
| int squirrel[] = {-1, -1, -1}; |
| int rcode; |
| debug_printf("non-subshell grouping\n"); |
| setup_redirects(child, squirrel); |
| /* XXX could we merge code with following builtin case, |
| * by creating a pseudo builtin that calls run_list_real? */ |
| rcode = run_list_real(child->group); |
| restore_redirects(squirrel); |
| return rcode; |
| } |
| for (i=0; is_assignment(child->argv[i]); i++) { /* nothing */ } |
| if (i!=0 && child->argv[i]==NULL) { |
| /* assignments, but no command: set the local environment */ |
| for (i=0; child->argv[i]!=NULL; i++) { |
| set_local_var(child->argv[i]); |
| } |
| return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */ |
| } |
| for (x = bltins; x->cmd; x++) { |
| if (strcmp(child->argv[i], x->cmd) == 0 ) { |
| int squirrel[] = {-1, -1, -1}; |
| int rcode; |
| if (x->function == builtin_exec && child->argv[i+1]==NULL) { |
| debug_printf("magic exec\n"); |
| setup_redirects(child,NULL); |
| return EXIT_SUCCESS; |
| } |
| debug_printf("builtin inline %s\n", child->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); |
| for (i=0; is_assignment(child->argv[i]); i++) { |
| putenv(strdup(child->argv[i])); |
| } |
| child->argv+=i; /* XXX horrible hack */ |
| rcode = x->function(child); |
| child->argv-=i; /* XXX restore hack so free() can work right */ |
| restore_redirects(squirrel); |
| return rcode; |
| } |
| } |
| } |
| |
| for (i = 0; i < pi->num_progs; i++) { |
| child = & (pi->progs[i]); |
| |
| /* pipes are inserted between pairs of commands */ |
| if ((i + 1) < pi->num_progs) { |
| if (pipe(pipefds)<0) perror_msg_and_die("pipe"); |
| nextout = pipefds[1]; |
| } else { |
| nextout=1; |
| pipefds[0] = -1; |
| } |
| |
| /* XXX test for failed fork()? */ |
| if (!(child->pid = fork())) { |
| |
| signal(SIGTTOU, SIG_DFL); |
| |
| close_all(); |
| |
| if (nextin != 0) { |
| dup2(nextin, 0); |
| close(nextin); |
| } |
| if (nextout != 1) { |
| dup2(nextout, 1); |
| close(nextout); |
| } |
| if (pipefds[0]!=-1) { |
| close(pipefds[0]); /* opposite end of our output pipe */ |
| } |
| |
| /* Like bash, explicit redirects override pipes, |
| * and the pipe fd is available for dup'ing. */ |
| setup_redirects(child,NULL); |
| |
| if (pi->followup!=PIPE_BG) { |
| /* Put our child in the process group whose leader is the |
| * first process in this pipe. */ |
| if (pi->pgrp < 0) { |
| pi->pgrp = child->pid; |
| } |
| /* Don't check for errors. The child may be dead already, |
| * in which case setpgid returns error code EACCES. */ |
| if (setpgid(0, pi->pgrp) == 0) { |
| signal(SIGTTOU, SIG_IGN); |
| tcsetpgrp(ctty, pi->pgrp); |
| signal(SIGTTOU, SIG_DFL); |
| } |
| } |
| |
| pseudo_exec(child); |
| } |
| /* Put our child in the process group whose leader is the |
| * first process in this pipe. */ |
| if (pi->pgrp < 0) { |
| pi->pgrp = child->pid; |
| } |
| /* Don't check for errors. The child may be dead already, |
| * in which case setpgid returns error code EACCES. */ |
| setpgid(child->pid, pi->pgrp); |
| |
| if (nextin != 0) |
| close(nextin); |
| if (nextout != 1) |
| close(nextout); |
| |
| /* If there isn't another process, nextin is garbage |
| but it doesn't matter */ |
| nextin = pipefds[0]; |
| } |
| return -1; |
| } |
| |
| static int run_list_real(struct pipe *pi) |
| { |
| int rcode=0; |
| int if_code=0, next_if_code=0; /* need double-buffer to handle elif */ |
| reserved_style rmode, skip_more_in_this_rmode=RES_XXXX; |
| for (;pi;pi=pi->next) { |
| rmode = pi->r_mode; |
| debug_printf("rmode=%d if_code=%d next_if_code=%d skip_more=%d\n", rmode, if_code, next_if_code, skip_more_in_this_rmode); |
| if (rmode == skip_more_in_this_rmode) continue; |
| skip_more_in_this_rmode = RES_XXXX; |
| if (rmode == RES_THEN || rmode == RES_ELSE) if_code = next_if_code; |
| if (rmode == RES_THEN && if_code) continue; |
| if (rmode == RES_ELSE && !if_code) continue; |
| if (rmode == RES_ELIF && !if_code) continue; |
| if (pi->num_progs == 0) continue; |
| rcode = run_pipe_real(pi); |
| if (rcode!=-1) { |
| /* We only ran a builtin: rcode was set by the return value |
| * of run_pipe_real(), and we don't need to wait for anything. */ |
| } else if (pi->followup==PIPE_BG) { |
| /* XXX check bash's behavior with nontrivial pipes */ |
| /* XXX compute jobid */ |
| /* XXX what does bash do with attempts to background builtins? */ |
| insert_bg_job(pi); |
| rcode = EXIT_SUCCESS; |
| } else { |
| |
| if (interactive) { |
| /* move the new process group into the foreground */ |
| /* suppress messages when run from /linuxrc mag@sysgo.de */ |
| //signal(SIGTTIN, SIG_IGN); |
| //signal(SIGTTOU, SIG_IGN); |
| if (tcsetpgrp(0, pi->pgrp) && errno != ENOTTY) |
| perror_msg("tcsetpgrp"); |
| rcode = pipe_wait(pi); |
| if (tcsetpgrp(0, getpgrp()) && errno != ENOTTY) |
| perror_msg("tcsetpgrp"); |
| //signal(SIGTTIN, SIG_DFL); |
| //signal(SIGTTOU, SIG_DFL); |
| } else { |
| rcode = pipe_wait(pi); |
| } |
| } |
| last_return_code=rcode; |
| if ( rmode == RES_IF || rmode == RES_ELIF ) |
| next_if_code=rcode; /* can be overwritten a number of times */ |
| if ( (rcode==EXIT_SUCCESS && pi->followup==PIPE_OR) || |
| (rcode!=EXIT_SUCCESS && pi->followup==PIPE_AND) ) |
| skip_more_in_this_rmode=rmode; |
| /* return rcode; */ /* XXX broken if list is part of if/then/else */ |
| } |
| checkjobs(); |
| return rcode; |
| } |
| |
| /* broken, of course, but OK for testing */ |
| static char *indenter(int i) |
| { |
| static char blanks[]=" "; |
| return &blanks[sizeof(blanks)-i-1]; |
| } |
| |
| /* return code is the exit status of the pipe */ |
| static int run_pipe_test(struct pipe *pi, int indent) |
| { |
| char **p; |
| struct child_prog *child; |
| struct redir_struct *r, *rnext; |
| int a, i, ret_code=0; |
| char *ind = indenter(indent); |
| final_printf("%s run pipe: (pid %d)\n",ind,getpid()); |
| for (i=0; i<pi->num_progs; i++) { |
| child = &pi->progs[i]; |
| final_printf("%s command %d:\n",ind,i); |
| if (child->argv) { |
| for (a=0,p=child->argv; *p; a++,p++) { |
| final_printf("%s argv[%d] = %s\n",ind,a,*p); |
| } |
| globfree(&child->glob_result); |
| child->argv=NULL; |
| } else if (child->group) { |
| final_printf("%s begin group (subshell:%d)\n",ind, child->subshell); |
| ret_code = run_list_test(child->group,indent+3); |
| final_printf("%s end group\n",ind); |
| } else { |
| final_printf("%s (nil)\n",ind); |
| } |
| for (r=child->redirects; r; r=rnext) { |
| final_printf("%s redirect %d%s", ind, r->fd, redir_table[r->type].descrip); |
| if (r->dup == -1) { |
| final_printf(" %s\n", *r->word.gl_pathv); |
| globfree(&r->word); |
| } else { |
| final_printf("&%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; |
| return ret_code; |
| } |
| |
| static int run_list_test(struct pipe *head, int indent) |
| { |
| int rcode=0; /* if list has no members */ |
| struct pipe *pi, *next; |
| char *ind = indenter(indent); |
| for (pi=head; pi; pi=next) { |
| if (pi->num_progs == 0) break; |
| final_printf("%s pipe reserved mode %d\n", ind, pi->r_mode); |
| rcode = run_pipe_test(pi, indent); |
| final_printf("%s pipe followup code %d\n", ind, pi->followup); |
| next=pi->next; |
| pi->next=NULL; |
| free(pi); |
| } |
| return rcode; |
| } |
| |
| /* Select which version we will use */ |
| static int run_list(struct pipe *pi) |
| { |
| int rcode=0; |
| if (fake_mode==0) { |
| rcode = run_list_real(pi); |
| } |
| /* run_list_test has the side effect of clearing memory |
| * In the long run that function can be merged with run_list_real, |
| * but doing that now would hobble the debugging effort. */ |
| run_list_test(pi,0); |
| return rcode; |
| } |
| |
| /* 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. |
| * Return code (0 vs. GLOB_NOSPACE) matches glob(3). |
| * XXX broken if the last character is '\\', check that before calling. |
| */ |
| static int globhack(const char *src, int flags, glob_t *pglob) |
| { |
| int cnt, pathc; |
| const char *s; |
| char *dest; |
| for (cnt=1, s=src; *s; s++) { |
| if (*s == '\\') s++; |
| cnt++; |
| } |
| dest = malloc(cnt); |
| if (!dest) return GLOB_NOSPACE; |
| if (!(flags & GLOB_APPEND)) { |
| pglob->gl_pathv=NULL; |
| pglob->gl_pathc=0; |
| pglob->gl_offs=0; |
| pglob->gl_offs=0; |
| } |
| pathc = ++pglob->gl_pathc; |
| pglob->gl_pathv = realloc(pglob->gl_pathv, (pathc+1)*sizeof(*pglob->gl_pathv)); |
| if (pglob->gl_pathv == NULL) return GLOB_NOSPACE; |
| pglob->gl_pathv[pathc-1]=dest; |
| pglob->gl_pathv[pathc]=NULL; |
| for (s=src; *s; s++, dest++) { |
| if (*s == '\\') s++; |
| *dest = *s; |
| } |
| *dest='\0'; |
| return 0; |
| } |
| |
| /* 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; |
| } |
| |
| #if 0 |
| static void globprint(glob_t *pglob) |
| { |
| int i; |
| debug_printf("glob_t at %p:\n", pglob); |
| debug_printf(" gl_pathc=%d gl_pathv=%p gl_offs=%d gl_flags=%d\n", |
| pglob->gl_pathc, pglob->gl_pathv, pglob->gl_offs, pglob->gl_flags); |
| for (i=0; i<pglob->gl_pathc; i++) |
| debug_printf("pglob->gl_pathv[%d] = %p = %s\n", i, |
| pglob->gl_pathv[i], pglob->gl_pathv[i]); |
| } |
| #endif |
| |
| static int xglob(o_string *dest, int flags, glob_t *pglob) |
| { |
| int gr; |
| |
| /* 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 */ |
| gr = globhack(dest->data, flags, pglob); |
| debug_printf("globhack returned %d\n",gr); |
| } else { |
| return 0; |
| } |
| } else if (glob_needed(dest->data)) { |
| gr = glob(dest->data, flags, NULL, pglob); |
| debug_printf("glob returned %d\n",gr); |
| if (gr == GLOB_NOMATCH) { |
| /* quote removal, or more accurately, backslash removal */ |
| gr = globhack(dest->data, flags, pglob); |
| debug_printf("globhack returned %d\n",gr); |
| } |
| } else { |
| gr = globhack(dest->data, flags, pglob); |
| debug_printf("globhack returned %d\n",gr); |
| } |
| if (gr == GLOB_NOSPACE) { |
| fprintf(stderr,"out of memory during glob\n"); |
| exit(1); |
| } |
| if (gr != 0) { /* GLOB_ABORTED ? */ |
| fprintf(stderr,"glob(3) error %d\n",gr); |
| } |
| /* globprint(glob_target); */ |
| return gr; |
| } |
| |
| |
| static int set_local_var(const char *s) |
| { |
| /* when you write this, also need to update lookup_param() */ |
| printf("assignment %s not handled: write me!\n",s); |
| return 0; |
| } |
| |
| static int is_assignment(const char *s) |
| { |
| if (s==NULL || !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 = xmalloc(sizeof(struct redir_struct)); |
| redir->next=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; |
| } |
| |
| struct pipe *new_pipe(void) { |
| struct pipe *pi; |
| pi = xmalloc(sizeof(struct pipe)); |
| pi->num_progs = 0; |
| pi->progs = NULL; |
| pi->next = NULL; |
| pi->followup = 0; /* invalid */ |
| return pi; |
| } |
| |
| static void initialize_context(struct p_context *ctx) |
| { |
| ctx->pipe=NULL; |
| ctx->pending_redirect=NULL; |
| ctx->child=NULL; |
| ctx->list_head=new_pipe(); |
| ctx->pipe=ctx->list_head; |
| ctx->w=RES_NONE; |
| 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. |
| */ |
| int reserved_word(o_string *dest, struct p_context *ctx) |
| { |
| struct reserved_combo { |
| char *literal; |
| int code; |
| long 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 struct reserved_combo reserved_list[] = { |
| { "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 }, |
| { "for", RES_FOR, FLAG_DO | FLAG_START }, |
| { "while", RES_WHILE, FLAG_DO | FLAG_START }, |
| { "until", RES_UNTIL, FLAG_DO | FLAG_START }, |
| { "do", RES_DO, FLAG_DONE }, |
| { "done", RES_DONE, FLAG_END } |
| }; |
| struct reserved_combo *r; |
| for (r=reserved_list; |
| #define NRES sizeof(reserved_list)/sizeof(struct reserved_combo) |
| r<reserved_list+NRES; r++) { |
| if (strcmp(dest->data, r->literal) == 0) { |
| debug_printf("found reserved word %s, code %d\n",r->literal,r->code); |
| if (r->flag & FLAG_START) { |
| struct p_context *new = xmalloc(sizeof(struct p_context)); |
| debug_printf("push stack\n"); |
| *new = *ctx; /* physical copy */ |
| initialize_context(ctx); |
| ctx->stack=new; |
| } else if ( ctx->w == RES_NONE || ! (ctx->old_flag & (1<<r->code))) { |
| syntax(); |
| ctx->w = RES_SNTX; |
| b_reset (dest); |
| return 1; |
| } |
| ctx->w=r->code; |
| ctx->old_flag = r->flag; |
| if (ctx->old_flag & FLAG_END) { |
| struct p_context *old; |
| debug_printf("pop stack\n"); |
| old = ctx->stack; |
| old->child->group = ctx->list_head; |
| *ctx = *old; /* physical copy */ |
| free(old); |
| } |
| b_reset (dest); |
| return 1; |
| } |
| } |
| return 0; |
| } |
| |
| /* 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; |
| glob_t *glob_target; |
| int gr, flags = 0; |
| |
| debug_printf("done_word: %s %p\n", dest->data, child); |
| if (dest->length == 0 && !dest->nonnull) { |
| debug_printf(" true null, ignored\n"); |
| return 0; |
| } |
| if (ctx->pending_redirect) { |
| glob_target = &ctx->pending_redirect->word; |
| } else { |
| if (child->group) { |
| syntax(); |
| return 1; /* syntax error, groups and arglists don't mix */ |
| } |
| if (!child->argv) { |
| debug_printf("checking %s for reserved-ness\n",dest->data); |
| if (reserved_word(dest,ctx)) return ctx->w==RES_SNTX; |
| } |
| glob_target = &child->glob_result; |
| if (child->argv) flags |= GLOB_APPEND; |
| } |
| gr = xglob(dest, flags, glob_target); |
| if (gr != 0) return 1; |
| |
| b_reset(dest); |
| if (ctx->pending_redirect) { |
| ctx->pending_redirect=NULL; |
| if (glob_target->gl_pathc != 1) { |
| fprintf(stderr, "ambiguous redirect\n"); |
| return 1; |
| } |
| } else { |
| child->argv = glob_target->gl_pathv; |
| } |
| 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. |
| * Only real trickiness here is that the uncommitted |
| * child structure, to which ctx->child points, is not |
| * counted in pi->num_progs. */ |
| struct pipe *pi=ctx->pipe; |
| struct child_prog *prog=ctx->child; |
| |
| if (prog && prog->group == NULL |
| && prog->argv == NULL |
| && prog->redirects == NULL) { |
| debug_printf("done_command: skipping null command\n"); |
| return 0; |
| } else if (prog) { |
| pi->num_progs++; |
| debug_printf("done_command: num_progs incremented to %d\n",pi->num_progs); |
| } else { |
| debug_printf("done_command: initializing\n"); |
| } |
| pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1)); |
| |
| prog = pi->progs + pi->num_progs; |
| prog->redirects = NULL; |
| prog->argv = NULL; |
| prog->is_stopped = 0; |
| prog->group = NULL; |
| prog->glob_result.gl_pathv = NULL; |
| prog->family = pi; |
| |
| ctx->child=prog; |
| /* but ctx->pipe and ctx->list_head remain unchanged */ |
| return 0; |
| } |
| |
| static int done_pipe(struct p_context *ctx, pipe_style type) |
| { |
| struct pipe *new_p; |
| done_command(ctx); /* implicit closure of previous command */ |
| debug_printf("done_pipe, type %d\n", type); |
| ctx->pipe->followup = type; |
| ctx->pipe->r_mode = ctx->w; |
| 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 */ |
| 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; |
| |
| fprintf(stderr, "ambiguous redirect\n"); |
| 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; |
| } |
| |
| FILE *generate_stream_from_list(struct pipe *head) |
| { |
| FILE *pf; |
| #if 1 |
| int pid, channel[2]; |
| if (pipe(channel)<0) perror_msg_and_die("pipe"); |
| pid=fork(); |
| if (pid<0) { |
| perror_msg_and_die("fork"); |
| } else if (pid==0) { |
| close(channel[0]); |
| if (channel[1] != 1) { |
| dup2(channel[1],1); |
| close(channel[1]); |
| } |
| #if 0 |
| #define SURROGATE "surrogate response" |
| write(1,SURROGATE,sizeof(SURROGATE)); |
| exit(run_list(head)); |
| #else |
| exit(run_list_real(head)); /* leaks memory */ |
| #endif |
| } |
| debug_printf("forked child %d\n",pid); |
| close(channel[1]); |
| pf = fdopen(channel[0],"r"); |
| debug_printf("pipe on FILE *%p\n",pf); |
| #else |
| run_list_test(head,0); |
| pf=popen("echo surrogate response","r"); |
| debug_printf("started fake pipe on FILE *%p\n",pf); |
| #endif |
| return pf; |
| } |
| |
| /* this version hacked for testing purposes */ |
| /* 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, int subst_end) |
| { |
| int retcode; |
| 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; |
| mark_open(fileno(p)); |
| setup_file_in_str(&pipe_str, p); |
| |
| /* now send results of command back into original context */ |
| retcode = parse_stream(dest, ctx, &pipe_str, '\0'); |
| /* XXX In case of a syntax error, should we try to kill the child? |
| * That would be tough to do right, so just read until EOF. */ |
| if (retcode == 1) { |
| while (b_getch(&pipe_str)!=EOF) { /* discard */ }; |
| } |
| |
| 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 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. */ |
| mark_closed(fileno(p)); |
| retcode=pclose(p); |
| debug_printf("pclosed, retcode=%d\n",retcode); |
| /* XXX this process fails to trim a single trailing newline */ |
| return retcode; |
| } |
| |
| static int parse_group(o_string *dest, struct p_context *ctx, |
| struct in_str *input, int ch) |
| { |
| int rcode, endch=0; |
| struct p_context sub; |
| struct child_prog *child = ctx->child; |
| if (child->argv) { |
| syntax(); |
| return 1; /* syntax error, groups and arglists don't mix */ |
| } |
| initialize_context(&sub); |
| switch(ch) { |
| case '(': endch=')'; child->subshell=1; break; |
| case '{': endch='}'; break; |
| default: syntax(); /* really logic error */ |
| } |
| rcode=parse_stream(dest,&sub,input,endch); |
| 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; |
| 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 void lookup_param(o_string *dest, struct p_context *ctx, o_string *src) |
| { |
| const char *p=NULL; |
| if (src->data) p = getenv(src->data); |
| if (p) parse_string(dest, ctx, p); /* recursion */ |
| b_free(src); |
| } |
| |
| /* 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 i, advance=0; |
| o_string alt=NULL_O_STRING; |
| char sep[]=" "; |
| int ch = input->peek(input); /* first character after the $ */ |
| debug_printf("handle_dollar: ch=%c\n",ch); |
| if (isalpha(ch)) { |
| while(ch=b_peek(input),isalnum(ch) || ch=='_') { |
| b_getch(input); |
| b_addchr(&alt,ch); |
| } |
| lookup_param(dest, ctx, &alt); |
| } else if (isdigit(ch)) { |
| i = ch-'0'; /* XXX is $0 special? */ |
| if (i<global_argc) { |
| parse_string(dest, ctx, global_argv[i]); /* recursion */ |
| } |
| advance = 1; |
| } else switch (ch) { |
| case '$': |
| b_adduint(dest,getpid()); |
| advance = 1; |
| break; |
| case '!': |
| if (last_bg_pid > 0) b_adduint(dest, last_bg_pid); |
| advance = 1; |
| break; |
| case '?': |
| b_adduint(dest,last_return_code); |
| advance = 1; |
| break; |
| case '#': |
| b_adduint(dest,global_argc ? global_argc-1 : 0); |
| advance = 1; |
| break; |
| case '{': |
| b_getch(input); |
| /* XXX maybe someone will try to escape the '}' */ |
| while(ch=b_getch(input),ch!=EOF && ch!='}') { |
| b_addchr(&alt,ch); |
| } |
| if (ch != '}') { |
| syntax(); |
| return 1; |
| } |
| lookup_param(dest, ctx, &alt); |
| break; |
| case '(': |
| b_getch(input); |
| process_command_subs(dest, ctx, input, ')'); |
| break; |
| case '*': |
| sep[0]=ifs[0]; |
| for (i=1; i<global_argc; i++) { |
| parse_string(dest, ctx, global_argv[i]); |
| if (i+1 < global_argc) parse_string(dest, ctx, sep); |
| } |
| break; |
| case '@': |
| case '-': |
| case '_': |
| /* still unhandled, but should be eventually */ |
| fprintf(stderr,"unhandled syntax: $%c\n",ch); |
| return 1; |
| break; |
| default: |
| b_addqchr(dest,'$',dest->quote); |
| } |
| /* Eat the character if the flag was set. If the compiler |
| * is smart enough, we could substitute "b_getch(input);" |
| * for all the "advance = 1;" above, and also end up with |
| * a nice size-optimized program. Hah! That'll be the day. |
| */ |
| if (advance) b_getch(input); |
| return 0; |
| } |
| |
| int parse_string(o_string *dest, struct p_context *ctx, const char *src) |
| { |
| struct in_str foo; |
| setup_string_in_str(&foo, src); |
| return parse_stream(dest, ctx, &foo, '\0'); |
| } |
| |
| /* return code is 0 for normal exit, 1 for syntax error */ |
| int parse_stream(o_string *dest, struct p_context *ctx, |
| struct in_str *input, int end_trigger) |
| { |
| unsigned int ch, m; |
| int redir_fd; |
| redir_type redir_style; |
| int next; |
| |
| /* Only double-quote state is handled in the state variable dest->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->quote. */ |
| |
| debug_printf("parse_stream, end_trigger=%d\n",end_trigger); |
| while ((ch=b_getch(input))!=EOF) { |
| m = map[ch]; |
| next = (ch == '\n') ? 0 : b_peek(input); |
| debug_printf("parse_stream: ch=%c (%d) m=%d quote=%d\n", |
| ch,ch,m,dest->quote); |
| if (m==0 || ((m==1 || m==2) && dest->quote)) { |
| b_addqchr(dest, ch, dest->quote); |
| } else { |
| if (m==2) { /* unquoted IFS */ |
| done_word(dest, ctx); |
| /* If we aren't performing a substitution, treat a newline as a |
| * command separator. */ |
| if (end_trigger != '\0' && ch=='\n') |
| done_pipe(ctx,PIPE_SEQ); |
| } |
| if (ch == end_trigger && !dest->quote && ctx->w==RES_NONE) { |
| debug_printf("leaving parse_stream\n"); |
| return 0; |
| } |
| #if 0 |
| if (ch=='\n') { |
| /* Yahoo! Time to run with it! */ |
| done_pipe(ctx,PIPE_SEQ); |
| run_list(ctx->list_head); |
| initialize_context(ctx); |
| } |
| #endif |
| if (m!=2) switch (ch) { |
| case '#': |
| if (dest->length == 0 && !dest->quote) { |
| while(ch=b_peek(input),ch!=EOF && ch!='\n') { b_getch(input); } |
| } else { |
| b_addqchr(dest, ch, dest->quote); |
| } |
| break; |
| case '\\': |
| if (next == EOF) { |
| syntax(); |
| return 1; |
| } |
| b_addqchr(dest, '\\', dest->quote); |
| b_addqchr(dest, b_getch(input), dest->quote); |
| break; |
| case '$': |
| if (handle_dollar(dest, ctx, input)!=0) return 1; |
| break; |
| case '\'': |
| dest->nonnull = 1; |
| while(ch=b_getch(input),ch!=EOF && ch!='\'') { |
| b_addchr(dest,ch); |
| } |
| if (ch==EOF) { |
| syntax(); |
| return 1; |
| } |
| break; |
| case '"': |
| dest->nonnull = 1; |
| dest->quote = !dest->quote; |
| break; |
| case '`': |
| process_command_subs(dest, ctx, input, '`'); |
| break; |
| case '>': |
| redir_fd = redirect_opt_num(dest); |
| done_word(dest, ctx); |
| redir_style=REDIRECT_OVERWRITE; |
| if (next == '>') { |
| redir_style=REDIRECT_APPEND; |
| b_getch(input); |
| } else if (next == '(') { |
| syntax(); /* until we support >(list) Process Substitution */ |
| return 1; |
| } |
| 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); |
| } else if (next == '(') { |
| syntax(); /* until we support <(list) Process Substitution */ |
| return 1; |
| } |
| 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) return 1; |
| break; |
| case ')': |
| case '}': |
| syntax(); /* Proper use of this character caught by end_trigger */ |
| return 1; |
| break; |
| default: |
| syntax(); /* this is really an internal logic error */ |
| return 1; |
| } |
| } |
| } |
| /* 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 != '\0', |
| * 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. */ |
| if (end_trigger != '\0') return -1; |
| return 0; |
| } |
| |
| void mapset(const unsigned char *set, int code) |
| { |
| const unsigned char *s; |
| for (s=set; *s; s++) map[*s] = code; |
| } |
| |
| void update_ifs_map(void) |
| { |
| /* char *ifs and char map[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 map[] array only really needs two bits each, and on most machines |
| * that would be faster because of the reduced L1 cache footprint. |
| */ |
| memset(map,0,256); /* most characters flow through always */ |
| mapset("\\$'\"`", 3); /* never flow through */ |
| mapset("<>;&|(){}#", 1); /* flow through if quoted */ |
| mapset(ifs, 2); /* also flow through if quoted */ |
| } |
| |
| /* most recursion does not come through here, the exeception is |
| * from builtin_source() */ |
| int parse_stream_outer(struct in_str *inp) |
| { |
| |
| struct p_context ctx; |
| o_string temp=NULL_O_STRING; |
| int rcode; |
| do { |
| initialize_context(&ctx); |
| update_ifs_map(); |
| inp->promptmode=1; |
| rcode = parse_stream(&temp, &ctx, inp, '\n'); |
| done_word(&temp, &ctx); |
| done_pipe(&ctx,PIPE_SEQ); |
| run_list(ctx.list_head); |
| } while (rcode != -1); /* loop on syntax errors, return on EOF */ |
| return 0; |
| } |
| |
| static int parse_string_outer(const char *s) |
| { |
| struct in_str input; |
| setup_string_in_str(&input, s); |
| return parse_stream_outer(&input); |
| } |
| |
| static int parse_file_outer(FILE *f) |
| { |
| int rcode; |
| struct in_str input; |
| setup_file_in_str(&input, f); |
| rcode = parse_stream_outer(&input); |
| return rcode; |
| } |
| |
| int shell_main(int argc, char **argv) |
| { |
| int opt; |
| FILE *input; |
| struct jobset joblist_end = { NULL, NULL }; |
| job_list = &joblist_end; |
| |
| last_return_code=EXIT_SUCCESS; |
| |
| /* XXX what should these be while sourcing /etc/profile? */ |
| global_argc = argc; |
| global_argv = argv; |
| |
| /* don't pay any attention to this signal; it just confuses |
| things and isn't really meant for shells anyway */ |
| signal(SIGTTOU, SIG_IGN); |
| |
| if (argv[0] && argv[0][0] == '-') { |
| debug_printf("\nsourcing /etc/profile\n"); |
| input = xfopen("/etc/profile", "r"); |
| mark_open(fileno(input)); |
| parse_file_outer(input); |
| mark_closed(fileno(input)); |
| fclose(input); |
| } |
| input=stdin; |
| |
| /* initialize the cwd -- this is never freed...*/ |
| cwd = xgetcwd(0); |
| if (!cwd) |
| cwd = unknown; |
| #ifdef BB_FEATURE_COMMAND_EDITING |
| cmdedit_set_initial_prompt(); |
| #else |
| PS1 = NULL; |
| #endif |
| |
| while ((opt = getopt(argc, argv, "c:xif")) > 0) { |
| switch (opt) { |
| case 'c': |
| { |
| global_argv = argv+optind; |
| global_argc = argc-optind; |
| opt = parse_string_outer(optarg); |
| goto final_return; |
| } |
| break; |
| case 'i': |
| interactive++; |
| break; |
| case 'f': |
| fake_mode++; |
| break; |
| default: |
| fprintf(stderr, "Usage: sh [FILE]...\n" |
| " or: sh -c command [args]...\n\n"); |
| exit(EXIT_FAILURE); |
| } |
| } |
| /* 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(fileno(stdin)) && isatty(fileno(stdout))) { |
| interactive++; |
| } |
| |
| debug_printf("\ninteractive=%d\n", interactive); |
| if (interactive) { |
| /* Looks like they want an interactive shell */ |
| fprintf(stdout, "\nhush -- the humble shell v0.01 (testing)\n\n"); |
| opt=parse_file_outer(stdin); |
| goto final_return; |
| } |
| |
| debug_printf("\nrunning script '%s'\n", argv[optind]); |
| global_argv = argv+optind; |
| global_argc = argc-optind; |
| input = xfopen(argv[optind], "r"); |
| opt = parse_file_outer(input); |
| |
| #ifdef BB_FEATURE_CLEAN_UP |
| fclose(input.file); |
| #endif |
| |
| final_return: |
| return(opt?opt:last_return_code); |
| } |