Rework environment variable handling to use wordexp, per a suggestion from
Larry Doolittle a couple of months ago. This makes the stuff-expansion in lash
be ever so standards compliant. This change needs testing by everyone, but
appears to be solid enough to let us close bug #1090.
It works for me; however, please test this change!
-Erik
diff --git a/sh.c b/sh.c
index 150055b..874c0ac 100644
--- a/sh.c
+++ b/sh.c
@@ -54,7 +54,7 @@
#include <ctype.h>
#include <errno.h>
#include <fcntl.h>
-#include <glob.h>
+#include <wordexp.h>
#include <signal.h>
#include <string.h>
#include <sys/ioctl.h>
@@ -96,8 +96,6 @@
char **argv; /* program name and arguments */
int num_redirects; /* elements in redirection array */
struct redir_struct *redirects; /* I/O redirects */
- glob_t glob_result; /* result of parameter globbing */
- int free_glob; /* should we globfree(&glob_result)? */
int is_stopped; /* is the program currently running? */
struct job *family; /* pointer back to the child's parent job */
};
@@ -209,9 +207,9 @@
static char **argv;
static struct close_me *close_me_head;
#ifdef BB_FEATURE_SH_ENVIRONMENT
-static int last_bg_pid=-1;
-static int last_return_code=-1;
-static int show_x_trace=FALSE;
+static int last_bg_pid;
+static int last_return_code;
+static int show_x_trace;
#endif
#ifdef BB_FEATURE_SH_IF_EXPRESSIONS
static char syntax_err[]="syntax error near unexpected token";
@@ -650,8 +648,6 @@
free(cmd->progs[i].argv);
if (cmd->progs[i].redirects)
free(cmd->progs[i].redirects);
- if (cmd->progs[i].free_glob)
- globfree(&cmd->progs[i].glob_result);
}
free(cmd->progs);
if (cmd->text)
@@ -875,7 +871,7 @@
}
/* remove trailing newline */
- command[strlen(command) - 1] = '\0';
+ chomp(command);
return 0;
}
@@ -900,125 +896,102 @@
*--b = '-';
return b;
}
+#endif
+
+static int expand_arguments(char *command)
+{
+#ifdef BB_FEATURE_SH_ENVIRONMENT
+ wordexp_t wrdexp;
+ char *src, *dst, *var;
+ int i=0, length, total_length=0, retval;
#endif
-static void expand_argument(struct child_prog *prog, int *argcPtr,
- int *argv_alloced_ptr)
-{
- int argc_l = *argcPtr;
- int argv_alloced = *argv_alloced_ptr;
- int rc;
- int flags;
- int i;
- char *src, *dst, *var;
+ /* get rid of the terminating \n */
+ chomp(command);
- if (argc_l > 1) { /* cmd->glob_result is already initialized */
- flags = GLOB_APPEND;
- i = prog->glob_result.gl_pathc;
- } else {
- prog->free_glob = 1;
- flags = 0;
- i = 0;
- }
#ifdef BB_FEATURE_SH_ENVIRONMENT
- /* do shell variable substitution */
- src = prog->argv[argc_l - 1];
+
+ /* This first part uses wordexp() which is a wonderful C lib
+ * function which expands nearly everything. */
+
+ retval = wordexp (command, &wrdexp, 0);
+
+ if (retval == WRDE_NOSPACE) {
+ /* Mem may have been allocated... */
+ wordfree (&wrdexp);
+ error_msg("out of space during expansion");
+ return FALSE;
+ }
+ if (retval < 0) {
+ /* Some other error. */
+ error_msg("syntax error");
+ return FALSE;
+ }
+
+ /* Convert from char** (one word per string) to a simple char*,
+ * but don't overflow command which is BUFSIZ in length */
+ *command = '\0';
+ while (i < wrdexp.we_wordc && total_length < BUFSIZ) {
+ length=strlen(wrdexp.we_wordv[i])+1;
+ if (BUFSIZ-total_length-length <= 0) {
+ error_msg("out of space during expansion");
+ return FALSE;
+ }
+ strcat(command+total_length, wrdexp.we_wordv[i++]);
+ strcat(command+total_length, " ");
+ total_length+=length;
+ }
+ wordfree (&wrdexp);
+
+
+ /* Now do the shell variable substitutions which
+ * wordexp can't do for us, namely $? and $! */
+ src = command;
while((dst = strchr(src,'$')) != NULL){
if (!(var = getenv(dst + 1))) {
switch(*(dst+1)) {
case '?':
var = itoa(last_return_code);
break;
- case '$':
- var = itoa(getpid());
- break;
- case '#':
- var = itoa(argc-1);
- break;
case '!':
if (last_bg_pid==-1)
*(var)='\0';
else
var = itoa(last_bg_pid);
break;
+#if 0
+ /* Everything else like $$, $#, $[0-9], etcshould all be
+ * expanded by wordexp(), so we can skip that stuff here */
+ case '$':
+ case '#':
case '0':case '1':case '2':case '3':case '4':
case '5':case '6':case '7':case '8':case '9':
- {
- int index=*(dst + 1)-48;
- if (index >= argc) {
- var='\0';
- } else {
- var = argv[index];
- }
- }
break;
+#endif
}
}
if (var) {
- int offset = dst-src;
-#warning I have a memory leak which needs to be plugged somehow
- src = (char*)xmalloc(strlen(src)-strlen(dst)+strlen(var)+1);
- strncpy(src, prog->argv[argc_l -1], offset);
- safe_strncpy(src+offset, var, strlen(var)+1);
- /* If there are any remaining $ variables in the src string, put them back */
- if ((dst = strchr(prog->argv[argc_l -1]+offset+1,'$')) != NULL) {
- offset=strlen(src);
- safe_strncpy(src+strlen(src), dst, strlen(dst)+1);
+ int subst_len = strlen(var);
+ char *next_dst;
+ if ((next_dst=strpbrk(dst+1, " \t~`!$^&*()=|\\{}[];\"'<>?")) == NULL) {
+ next_dst = dst;
}
- prog->argv[argc_l -1] = src;
- } else {
- memset(dst, 0, strlen(src)-strlen(dst));
+ src = (char*)xrealloc(src, strlen(src) - strlen(next_dst)+strlen(var)+1);
+ /* Move stuff to the end of the string to accommodate filling
+ * the created gap with the new stuff */
+ memmove(dst+subst_len, next_dst+1, subst_len);
+ /* Now copy in the new stuff */
+ strncpy(dst, var, subst_len);
}
+ src = dst;
+ src++;
}
-#endif
- if (strpbrk(prog->argv[argc_l - 1],"*[]?")!= NULL){
- rc = glob(prog->argv[argc_l - 1], flags, NULL, &prog->glob_result);
- if (rc == GLOB_NOSPACE) {
- error_msg("out of space during glob operation");
- return;
- } else if (rc == GLOB_NOMATCH ||
- (!rc && (prog->glob_result.gl_pathc - i) == 1 &&
- strcmp(prog->argv[argc_l - 1],
- prog->glob_result.gl_pathv[i]) == 0)) {
- /* we need to remove whatever \ quoting is still present */
- src = dst = prog->argv[argc_l - 1];
- while (*src) {
- if (*src == '\\') {
- src++;
- *dst++ = process_escape_sequence(&src);
- } else {
- *dst++ = *src;
- src++;
- }
- }
- *dst = '\0';
- } else if (!rc) {
- argv_alloced += (prog->glob_result.gl_pathc - i);
- prog->argv = xrealloc(prog->argv, argv_alloced * sizeof(*prog->argv));
- memcpy(prog->argv + (argc_l - 1), prog->glob_result.gl_pathv + i,
- sizeof(*(prog->argv)) * (prog->glob_result.gl_pathc - i));
- argc_l += (prog->glob_result.gl_pathc - i - 1);
- }
- }else{
- src = dst = prog->argv[argc_l - 1];
- while (*src) {
- if (*src == '\\') {
- src++;
- *dst++ = process_escape_sequence(&src);
- } else {
- *dst++ = *src;
- src++;
- }
- }
- *dst = '\0';
-
- prog->glob_result.gl_pathc=0;
- if (flags==0)
- prog->glob_result.gl_pathv=NULL;
- }
- *argv_alloced_ptr = argv_alloced;
- *argcPtr = argc_l;
+
+
+
+#endif
+ return TRUE;
}
/* Return cmd->num_progs as 0 if no command is present (e.g. an empty
@@ -1066,7 +1039,6 @@
prog = job->progs;
prog->num_redirects = 0;
prog->redirects = NULL;
- prog->free_glob = 0;
prog->is_stopped = 0;
prog->family = job;
@@ -1106,7 +1078,6 @@
sizeof(*prog->argv) *
argv_alloced);
}
- expand_argument(prog, &argc_l, &argv_alloced);
prog->argv[argc_l] = buf;
}
} else
@@ -1139,7 +1110,6 @@
if (*chptr && *prog->argv[argc_l]) {
buf++, argc_l++;
- expand_argument(prog, &argc_l, &argv_alloced);
prog->argv[argc_l] = buf;
}
}
@@ -1200,7 +1170,6 @@
prog = job->progs + (job->num_progs - 1);
prog->num_redirects = 0;
prog->redirects = NULL;
- prog->free_glob = 0;
prog->is_stopped = 0;
prog->family = job;
argc_l = 0;
@@ -1356,7 +1325,6 @@
if (*prog->argv[argc_l]) {
argc_l++;
- expand_argument(prog, &argc_l, &argv_alloced);
}
if (!argc_l) {
free_job(job);
@@ -1624,6 +1592,13 @@
next_command = command;
}
+ if (expand_arguments(next_command) == FALSE) {
+ free(command);
+ command = (char *) xcalloc(BUFSIZ, sizeof(char));
+ next_command = NULL;
+ continue;
+ }
+
if (!parse_command(&next_command, &newjob, &inbg) &&
newjob.num_progs) {
int pipefds[2] = {-1,-1};
@@ -1723,8 +1698,8 @@
job_list.head = NULL;
job_list.fg = NULL;
#ifdef BB_FEATURE_SH_ENVIRONMENT
- last_bg_pid=-1;
- last_return_code=-1;
+ last_bg_pid=1;
+ last_return_code=1;
show_x_trace=FALSE;
#endif