getopt32 must remain NOFORK-safe (no mallocs!). Using alloca and pretending

stack is infinite. Unfortunately, +79 bytes.

1 files changed, 4 insertions, 7 deletions

diff --git a/libbb/getopt32.c b/libbb/getopt32.c
index e5d97e98c..25eb113df 100644
--- a/libbb/getopt32.c
+++ b/libbb/getopt32.c
@@ -307,7 +307,7 @@ getopt32(int argc, char **argv, const char *applet_opts, ...)
         va_list p;
 #if ENABLE_GETOPT_LONG
         const struct option *l_o;
-        struct option *long_options = NULL;
+        struct option *long_options = (struct option *) &bb_null_long_options;
 #endif
         unsigned trigger;
         char **pargv = NULL;
@@ -350,11 +350,11 @@ getopt32(int argc, char **argv, const char *applet_opts, ...)
                 count = 1;
                 optstr = applet_long_options;
                 while (optstr[0]) {
-                        optstr += strlen(optstr) + 3; /* skip \0, has_arg, val */
+                        optstr += strlen(optstr) + 3; /* skip NUL, has_arg, val */
                         count++;
                 }
                 /* count == no. of longopts + 1 */
-                long_options = xzalloc(count * sizeof(*long_options));
+                long_options = alloca(count * sizeof(*long_options));
                 i = 0;
                 optstr = applet_long_options;
                 while (--count) {
@@ -476,7 +476,7 @@ getopt32(int argc, char **argv, const char *applet_opts, ...)
          * (supposed to act as --header, but doesn't) */
 #if ENABLE_GETOPT_LONG
         while ((c = getopt_long(argc, argv, applet_opts,
-                        long_options ? long_options : bb_null_long_options, NULL)) != -1) {
+                        long_options, NULL)) != -1) {
 #else
         while ((c = getopt(argc, argv, applet_opts)) != -1) {
 #endif
@@ -535,9 +535,6 @@ getopt32(int argc, char **argv, const char *applet_opts, ...)
         if (argc < min_arg || (max_arg >= 0 && argc > max_arg))
                 bb_show_usage();
 
-#if ENABLE_GETOPT_LONG
-        free(long_options);
-#endif
         option_mask32 = flags;
         return flags;
 }