use alloca() instead of malloc()

diff --git a/lib/libc/gen/exec.c b/lib/libc/gen/exec.c
index 8bac51e..3ae2660 100644 (file)
--- a/lib/libc/gen/exec.c
+++ b/lib/libc/gen/exec.c
@@ -1,4 +1,4 @@
-/*     $NetBSD: exec.c,v 1.6 1995/02/27 03:42:57 cgd Exp $     */
+/*     $NetBSD: exec.c,v 1.7 1995/12/14 16:51:27 jtc Exp $     */
 
 /*-
  * Copyright (c) 1991, 1993
@@ -37,7 +37,7 @@
 #if 0
 static char sccsid[] = "@(#)exec.c     8.1 (Berkeley) 6/4/93";
 #else
-static char rcsid[] = "$NetBSD: exec.c,v 1.6 1995/02/27 03:42:57 cgd Exp $";
+static char rcsid[] = "$NetBSD: exec.c,v 1.7 1995/12/14 16:51:27 jtc Exp $";
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -58,39 +58,6 @@ static char rcsid[] = "$NetBSD: exec.c,v 1.6 1995/02/27 03:42:57 cgd Exp $";
 
 extern char **environ;
 
-static char **
-buildargv(ap, arg, envpp)
-       va_list ap;
-       const char *arg;
-       char ***envpp;
-{
-       static size_t memsize;
-       static char **argv;
-       register size_t off;
-
-       argv = NULL;
-       for (off = 0;; ++off) {
-               if (off >= memsize) {
-                       memsize += 50;  /* Starts out at 0. */
-                       memsize *= 2;   /* Ramp up fast. */
-                       if (!(argv = realloc(argv, memsize * sizeof(char *)))) {
-                               memsize = 0;
-                               return (NULL);
-                       }
-                       if (off == 0) {
-                               argv[0] = (char *)arg;
-                               off = 1;
-                       }
-               }
-               if (!(argv[off] = va_arg(ap, char *)))
-                       break;
-       }
-       /* Get environment pointer if user supposed to provide one. */
-       if (envpp)
-               *envpp = va_arg(ap, char **);
-       return (argv);
-}
-
 int
 #if __STDC__
 execl(const char *name, const char *arg, ...)
@@ -102,21 +69,31 @@ execl(name, arg, va_alist)
 #endif
 {
        va_list ap;
-       int sverrno;
        char **argv;
+       int i;
 
 #if __STDC__
        va_start(ap, arg);
 #else
        va_start(ap);
 #endif
-       if (argv = buildargv(ap, arg, NULL))
-               (void)execve(name, argv, environ);
+       for (i = 1; va_arg(ap, char *) != NULL; i++)
+               ;
        va_end(ap);
-       sverrno = errno;
-       free(argv);
-       errno = sverrno;
-       return (-1);
+
+       argv = alloca (i * sizeof (char *));
+       
+#if __STDC__
+       va_start(ap, arg);
+#else
+       va_start(ap);
+#endif
+       argv[0] = (char *) arg;
+       for (i = 1; (argv[i] = (char *) va_arg(ap, char *)) != NULL; i++) 
+               ;
+       va_end(ap);
+       
+       return execve(name, argv, environ);
 }
 
 int
@@ -130,21 +107,32 @@ execle(name, arg, va_alist)
 #endif
 {
        va_list ap;
-       int sverrno;
        char **argv, **envp;
+       int i;
 
 #if __STDC__
        va_start(ap, arg);
 #else
        va_start(ap);
 #endif
-       if (argv = buildargv(ap, arg, &envp))
-               (void)execve(name, argv, envp);
+       for (i = 1; va_arg(ap, char *) != NULL; i++)
+               ;
        va_end(ap);
-       sverrno = errno;
-       free(argv);
-       errno = sverrno;
-       return (-1);
+
+       argv = alloca (i * sizeof (char *));
+       
+#if __STDC__
+       va_start(ap, arg);
+#else
+       va_start(ap);
+#endif
+       argv[0] = (char *) arg;
+       for (i = 1; (argv[i] = (char *) va_arg(ap, char *)) != NULL; i++) 
+               ;
+       envp = (char **) va_arg(ap, char **);
+       va_end(ap);
+
+       return execve(name, argv, envp);
 }
 
 int
@@ -158,21 +146,31 @@ execlp(name, arg, va_alist)
 #endif
 {
        va_list ap;
-       int sverrno;
        char **argv;
+       int i;
 
 #if __STDC__
        va_start(ap, arg);
 #else
        va_start(ap);
 #endif
-       if (argv = buildargv(ap, arg, NULL))
-               (void)execvp(name, argv);
+       for (i = 1; va_arg(ap, char *) != NULL; i++)
+               ;
        va_end(ap);
-       sverrno = errno;
-       free(argv);
-       errno = sverrno;
-       return (-1);
+
+       argv = alloca (i * sizeof (char *));
+       
+#if __STDC__
+       va_start(ap, arg);
+#else
+       va_start(ap);
+#endif
+       argv[0] = (char *) arg;
+       for (i = 1; (argv[i] = va_arg(ap, char *)) != NULL; i++) 
+               ;
+       va_end(ap);
+       
+       return execvp(name, argv);
 }
 
 int
@@ -180,8 +178,7 @@ execv(name, argv)
        const char *name;
        char * const *argv;
 {
-       (void)execve(name, argv, environ);
-       return (-1);
+       return execve(name, argv, environ);
 }
 
 int