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-rw-r--r--posix/execl.c53
1 files changed, 29 insertions, 24 deletions
diff --git a/posix/execl.c b/posix/execl.c
index 7f822d0142..62fd45db58 100644
--- a/posix/execl.c
+++ b/posix/execl.c
@@ -1,4 +1,4 @@
-/* Copyright (C) 1991,92,94,97,98,99,2002,2005 Free Software Foundation, Inc.
+/* Copyright (C) 1991,92,94,97,98,99,2002 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -16,58 +16,63 @@
    Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA.  */
 
+#include <alloca.h>
 #include <unistd.h>
 #include <stdarg.h>
 #include <stddef.h>
-#include <stdlib.h>
 #include <string.h>
 
 #include <stackinfo.h>
 
+#ifndef	HAVE_GNU_LD
+# define __environ	environ
+#endif
 
 /* Execute PATH with all arguments after PATH until
    a NULL pointer and environment from `environ'.  */
 int
 execl (const char *path, const char *arg, ...)
 {
-#define INITIAL_ARGV_MAX 1024
-  size_t argv_max = INITIAL_ARGV_MAX;
-  const char *initial_argv[INITIAL_ARGV_MAX];
-  const char **argv = initial_argv;
+  size_t argv_max = 1024;
+  const char **argv = alloca (argv_max * sizeof (const char *));
+  unsigned int i;
   va_list args;
 
   argv[0] = arg;
 
   va_start (args, arg);
-  unsigned int i = 0;
+  i = 0;
   while (argv[i++] != NULL)
     {
       if (i == argv_max)
 	{
-	  argv_max *= 2;
-	  const char **nptr = realloc (argv == initial_argv ? NULL : argv,
-				       argv_max * sizeof (const char *));
-	  if (nptr == NULL)
+	  const char **nptr = alloca ((argv_max *= 2) * sizeof (const char *));
+
+#ifndef _STACK_GROWS_UP
+	  if ((char *) nptr + argv_max == (char *) argv)
 	    {
-	      if (argv != initial_argv)
-		free (argv);
-	      return -1;
+	      /* Stack grows down.  */
+	      argv = (const char **) memcpy (nptr, argv,
+					     i * sizeof (const char *));
+	      argv_max += i;
 	    }
-	  if (argv == initial_argv)
-	    /* We have to copy the already filled-in data ourselves.  */
-	    memcpy (nptr, argv, i * sizeof (const char *));
-
-	  argv = nptr;
+	  else
+#endif
+#ifndef _STACK_GROWS_DOWN
+	    if ((char *) argv + i == (char *) nptr)
+	    /* Stack grows up.  */
+	    argv_max += i;
+	  else
+#endif
+	    /* We have a hole in the stack.  */
+	    argv = (const char **) memcpy (nptr, argv,
+					   i * sizeof (const char *));
 	}
 
       argv[i] = va_arg (args, const char *);
     }
   va_end (args);
 
-  int ret = __execve (path, (char *const *) argv, __environ);
-  if (argv != initial_argv)
-    free (argv);
-
-  return ret;
+  return __execve (path, (char *const *) argv, __environ);
 }
 libc_hidden_def (execl)