hush: simplify read builtin; fix set_local_var (misplaced 'goto skip;')

1 files changed, 18 insertions, 42 deletions

diff --git a/shell/hush.c b/shell/hush.c
index e3dd6663e..2e78e4a04 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -854,32 +854,24 @@ static int builtin_pwd(char **argv ATTRIBUTE_UNUSED)
 /* built-in 'read VAR' handler */
 static int builtin_read(char **argv)
 {
-        int res;
+        char string[BUFSIZ];
+        char *p;
+        const char *name = argv[1] ? argv[1] : "REPLY";
+        int name_len = strlen(name);
 
-        if (argv[1]) {
-                char string[BUFSIZ];
-                char *var = NULL;
-
-                string[0] = '\0';  /* In case stdin has only EOF */
-                /* read string */
-                fgets(string, sizeof(string), stdin);
-                chomp(string);
-                var = malloc(strlen(argv[1]) + strlen(string) + 2);
-                if (var) {
-                        sprintf(var, "%s=%s", argv[1], string);
-                        res = set_local_var(var, 0);
-                } else
-                        res = -1;
-                if (res)
-                        bb_perror_msg("read");
-                free(var);      /* So not move up to avoid breaking errno */
-                return res;
-        }
-        do res = getchar(); while (res != '\n' && res != EOF);
-        return 0;
+        if (name_len >= sizeof(string) - 2)
+                return EXIT_FAILURE;
+        strcpy(string, name);
+        p = string + name_len;
+        *p++ = '=';
+        *p = '\0'; /* In case stdin has only EOF */
+        /* read string. name_len+1 chars are already used by 'name=' */
+        fgets(p, sizeof(string) - 1 - name_len, stdin);
+        chomp(p);
+        return set_local_var(string, 0);
 }
 
-/* built-in 'set VAR=value' handler */
+/* built-in 'set [VAR=value]' handler */
 static int builtin_set(char **argv)
 {
         char *temp = argv[1];
@@ -959,7 +951,7 @@ static int builtin_umask(char **argv)
 /* built-in 'unset VAR' handler */
 static int builtin_unset(char **argv)
 {
-        /* bash returned already true */
+        /* bash always returns true */
         unset_local_var(argv[1]);
         return EXIT_SUCCESS;
 }
@@ -2418,8 +2410,6 @@ static int expand_on_ifs(char **list, int n, char **posp, const char *str)
  * to be filled). This routine is extremely tricky: has to deal with
  * variables/parameters with whitespace, $* and $@, and constructs like
  * 'echo -$*-'. If you play here, you must run testsuite afterwards! */
-/* NB: support for double-quoted expansion is not used yet (we never set
- * magic bit 0x80 elsewhere...) */
 /* NB: another bug is that we cannot detect empty strings yet:
  * "" or $empty"" expands to zero words, has to expand to empty word */
 static int expand_vars_to_list(char **list, int n, char **posp, char *arg)
@@ -2663,20 +2653,6 @@ static char *insert_var_value(char *inp)
 }
 
 
-
-
-
-
-
-
-
-
-
-
-
-
-
-
 /* This is used to get/check local shell variables */
 static const char *get_local_var(const char *s)
 {
@@ -2717,7 +2693,7 @@ static int set_local_var(const char *s, int flg_export)
         for (cur = top_vars; cur; cur = cur->next) {
                 if (strcmp(cur->name, name) == 0) {
                         if (strcmp(cur->value, value) == 0) {
-                                if (flg_export > 0 && cur->flg_export == 0)
+                                if (flg_export && !cur->flg_export)
                                         cur->flg_export = flg_export;
                                 else
                                         result++;
@@ -2730,8 +2706,8 @@ static int set_local_var(const char *s, int flg_export)
                                 free((char*)cur->value);
                                 cur->value = strdup(value);
                         }
+                        goto skip;
                 }
-                goto skip;
         }
 
 // TODO: need simpler/generic rollback on malloc failure - see ash