Updates from both Vladimir and Larry

git-svn-id: svn://busybox.net/trunk/busybox@2706 69ca8d6d-28ef-0310-b511-8ec308f3f277

1 files changed, 89 insertions, 64 deletions

diff --git a/shell/hush.c b/shell/hush.c
index 722dcf7ac..2b100983e 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -256,10 +256,8 @@ static const char *cwd;
 static struct jobset *job_list;
 static unsigned int last_bg_pid;
 static char *PS1;
-static char PS2[] = "> ";
-
+static char *PS2;
 struct variables shell_ver = { "HUSH_VERSION", "0.01", 1, 1, 0 };
-
 struct variables *top_vars = &shell_ver;
 
 #define B_CHUNK (100)
@@ -505,29 +503,29 @@ static int builtin_export(struct child_prog *child)
         name = strdup(name);
 
         if(name) {
-            char *value = strchr(name, '=');
-
-        if (!value) {
-                char *tmp;
-                /* They are exporting something without an =VALUE */
-
-                value = get_local_var(name);
-                if (value) {
-                        size_t ln = strlen(name);
-
-                        tmp = realloc(name, ln+strlen(value)+2);
-                        if(tmp==NULL)
-                                res = -1;
-                        else {
-                                sprintf(tmp+ln, "=%s", value);
-                                name = tmp;
+                char *value = strchr(name, '=');
+
+                if (!value) {
+                        char *tmp;
+                        /* They are exporting something without an =VALUE */
+
+                        value = get_local_var(name);
+                        if (value) {
+                                size_t ln = strlen(name);
+
+                                tmp = realloc(name, ln+strlen(value)+2);
+                                if(tmp==NULL)
+                                        res = -1;
+                                else {
+                                        sprintf(tmp+ln, "=%s", value);
+                                        name = tmp;
+                                }
+                        } else {
+                                /* bash does not return an error when trying to export
+                                 * an undefined variable.  Do likewise. */
+                                res = 1;
                         }
-                } else {
-                        /* bash not put error and set error code
-                           if exporting not defined variable */
-                        res = 1;
                 }
-            }
         }
         if (res<0)
                 perror_msg("export");
@@ -641,7 +639,7 @@ static int builtin_read(struct child_prog *child)
                 char string[BUFSIZ];
                 char *var = 0;
 
-                string[0] = 0;  /* for correct work if stdin have "only EOF" */
+                string[0] = 0;  /* In case stdin has only EOF */
                 /* read string */
                 fgets(string, sizeof(string), stdin);
                 chomp(string);
@@ -650,10 +648,10 @@ static int builtin_read(struct child_prog *child)
                         sprintf(var, "%s=%s", child->argv[1], string);
                         res = set_local_var(var, 0);
                 } else
-                res = -1;
+                        res = -1;
                 if (res)
                         fprintf(stderr, "read: %m\n");
-                free(var);      /* not move up - saved errno */
+                free(var);      /* So not move up to avoid breaking errno */
                 return res;
         } else {
                 do res=getchar(); while(res!='\n' && res!=EOF);
@@ -1061,6 +1059,9 @@ static int pipe_wait(struct pipe *pi)
 }
 
 /* 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? */
 static void pseudo_exec(struct child_prog *child)
 {
         int i, rcode;
@@ -1076,7 +1077,9 @@ static void pseudo_exec(struct child_prog *child)
                 /* If a variable is assigned in a forest, and nobody listens,
                  * was it ever really set?
                  */
-                if (child->argv[0] == NULL) exit(EXIT_SUCCESS);
+                if (child->argv[0] == NULL) {
+                        _exit(EXIT_SUCCESS);
+                }
 
                 /*
                  * Check if the command matches any of the builtins.
@@ -1087,7 +1090,7 @@ static void pseudo_exec(struct child_prog *child)
                 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));
+                                _exit(x->function(child));
                         }
                 }
 
@@ -1128,18 +1131,18 @@ static void pseudo_exec(struct child_prog *child)
                 debug_printf("exec of %s\n",child->argv[0]);
                 execvp(child->argv[0],child->argv);
                 perror_msg("couldn't exec: %s",child->argv[0]);
-                exit(1);
+                _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);
+                _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);
+                _exit(EXIT_SUCCESS);
         }
 }
 
@@ -1713,23 +1716,29 @@ static int set_local_var(const char *s, int flg_export)
         } else {
                 *value++ = 0;
 
-                for(cur = top_vars; cur; cur = cur->next)
+                for(cur = top_vars; cur; cur = cur->next) {
                         if(strcmp(cur->name, name)==0)
-                        break;
+                                break;
+                }
 
                 if(cur) {
                         if(strcmp(cur->value, value)==0) {
-                                result = cur->flg_export == flg_export;
+                                if(flg_export>0 && cur->flg_export==0)
+                                        cur->flg_export=flg_export;
+                                else
+                                        result++;
                         } else {
                                 if(cur->flg_read_only) {
-                        result = -1;
+                                        result = -1;
                                         error_msg("%s: readonly variable", name);
                                 } else {
+                                        if(flg_export>0 || cur->flg_export>1)
+                                                cur->flg_export=1;
                                         free(cur->value);
                                         cur->value = newval;
                                         newval = 0; /* protect free */
-                }
-        }
+                                }
+                        }
                 } else {
                         cur = malloc(sizeof(struct variables));
                         if(cur==0) {
@@ -1738,10 +1747,9 @@ static int set_local_var(const char *s, int flg_export)
                                 cur->name = strdup(name);
                                 if(cur->name == 0) {
                                         free(cur);
-                                result = -1;
+                                        result = -1;
                                 } else {
                                         struct variables *bottom = top_vars;
-
                                         cur->value = newval;
                                         newval = 0;     /* protect free */
                                         cur->next = 0;
@@ -1749,16 +1757,16 @@ static int set_local_var(const char *s, int flg_export)
                                         cur->flg_read_only = 0;
                                         while(bottom->next) bottom=bottom->next;
                                         bottom->next = cur;
+                                }
                         }
                 }
         }
-        }
 
-        if((result==0 && flg_export==1) || (result>0 && cur->flg_export>0)) {
+        if(result==0 && cur->flg_export==1) {
                 *(value-1) = '=';
                 result = putenv(name);
         } else {
-        free(name);
+                free(name);
                 if(result>0)            /* equivalent to previous set */
                         result = 0;
         }
@@ -1771,14 +1779,16 @@ static void unset_local_var(const char *name)
         struct variables *cur;
 
         if (name) {
-                for (cur = top_vars; cur; cur=cur->next)
+                for (cur = top_vars; cur; cur=cur->next) {
                         if(strcmp(cur->name, name)==0)
                                 break;
+                }
                 if(cur!=0) {
                         struct variables *next = top_vars;
-                        if(cur==next)
-                return;
-                        else {
+                        if(cur->flg_read_only) {
+                                error_msg("%s: readonly variable", name);
+                                return;
+                        } else {
                                 if(cur->flg_export)
                                         unsetenv(cur->name);
                                 free(cur->name);
@@ -2103,9 +2113,9 @@ FILE *generate_stream_from_list(struct pipe *head)
 #if 0
 #define SURROGATE "surrogate response"
                 write(1,SURROGATE,sizeof(SURROGATE));
-                exit(run_list(head));
+                _exit(run_list(head));
 #else
-                exit(run_list_real(head));   /* leaks memory */
+                _exit(run_list_real(head));   /* leaks memory */
 #endif
         }
         debug_printf("forked child %d\n",pid);
@@ -2531,18 +2541,43 @@ int shell_main(int argc, char **argv)
         struct jobset joblist_end = { NULL, NULL };
         char **e = environ;
 
-        /* initialize globals */
+        /* FIXME */
+        fprintf(stderr, "sizeof(map)=%d\n", sizeof(map));
+
+
+        /* XXX what should these be while sourcing /etc/profile? */
+        global_argc = argc;
+        global_argv = argv;
+        
+        /* (re?) initialize globals.  Sometimes shell_main() ends up calling
+         * shell_main(), therefore we cannot rely on the BSS to zero out this 
+         * stuff.  Reset these to 0 every time. */
+        ifs = NULL;
+        memset(map,0,sizeof(map));
+        fake_mode = 0;
+        interactive = 0;
+        close_me_head = NULL;
+        last_bg_pid = 0;
+
+        /* Initialize some more globals to non-zero values */
+        set_cwd();
+        job_list = &joblist_end;
+#ifdef BB_FEATURE_COMMAND_EDITING
+        cmdedit_set_initial_prompt();
+#else
+        PS1 = NULL;
+#endif
+        PS2 = "> ";
+
+        /* initialize our shell local variables with the values 
+         * currently living in the environment */
         if (e) {
                 for (; *e; e++)
                         set_local_var(*e, 2);   /* without call putenv() */
         }
-        job_list = &joblist_end;
 
         last_return_code=EXIT_SUCCESS;
 
-        /* XXX what should these be while sourcing /etc/profile? */
-        global_argc = argc;
-        global_argv = argv;
 
         /* If we get started under a job aware app (like bash 
          * for example), make sure we are now in charge so we 
@@ -2563,16 +2598,6 @@ int shell_main(int argc, char **argv)
         }
         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':