--- Libc/Libc-498/gen/FreeBSD/exec.c
+++ Libc/Libc-1698.100.8/gen/FreeBSD/exec.c
@@ -1,4 +1,6 @@
 /*-
+ * SPDX-License-Identifier: BSD-3-Clause
+ *
  * Copyright (c) 1991, 1993
  *	The Regents of the University of California.  All rights reserved.
  *
@@ -10,11 +12,7 @@
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
- * 3. All advertising materials mentioning features or use of this software
- *    must display the following acknowledgement:
- *	This product includes software developed by the University of
- *	California, Berkeley and its contributors.
- * 4. Neither the name of the University nor the names of its contributors
+ * 3. Neither the name of the University nor the names of its contributors
  *    may be used to endorse or promote products derived from this software
  *    without specific prior written permission.
  *
@@ -35,11 +33,10 @@
 static char sccsid[] = "@(#)exec.c	8.1 (Berkeley) 6/4/93";
 #endif /* LIBC_SCCS and not lint */
 #include <sys/cdefs.h>
-__FBSDID("$FreeBSD: src/lib/libc/gen/exec.c,v 1.22 2003/07/01 12:30:03 bde Exp $");
+__FBSDID("$FreeBSD: src/lib/libc/gen/exec.c,v 1.27 2009/12/05 18:55:16 ed Exp $");
 
 #include "namespace.h"
 #include <sys/param.h>
-#include <sys/types.h>
 #include <sys/stat.h>
 #include <errno.h>
 #include <unistd.h>
@@ -50,14 +47,19 @@
 
 #include <stdarg.h>
 #include "un-namespace.h"
-
-extern char **environ;
+#include "libc_private.h"
+
+#include <crt_externs.h>
+#define environ (*_NSGetEnviron())
+
+int
+_execvpe(const char *name, char * const argv[], char * const envp[]);
 
 int
 execl(const char *name, const char *arg, ...)
 {
 	va_list ap;
-	char **argv;
+	const char **argv;
 	int n;
 
 	va_start(ap, arg);
@@ -72,18 +74,19 @@
 	}
 	va_start(ap, arg);
 	n = 1;
-	argv[0] = (char *)arg;
+	argv[0] = arg;
 	while ((argv[n] = va_arg(ap, char *)) != NULL)
 		n++;
 	va_end(ap);
-	return (_execve(name, argv, environ));
+	return (_execve(name, __DECONST(char **, argv), environ));
 }
 
 int
 execle(const char *name, const char *arg, ...)
 {
 	va_list ap;
-	char **argv, **envp;
+	const char **argv;
+	char **envp;
 	int n;
 
 	va_start(ap, arg);
@@ -98,19 +101,19 @@
 	}
 	va_start(ap, arg);
 	n = 1;
-	argv[0] = (char *)arg;
+	argv[0] = arg;
 	while ((argv[n] = va_arg(ap, char *)) != NULL)
 		n++;
 	envp = va_arg(ap, char **);
 	va_end(ap);
-	return (_execve(name, argv, envp));
+	return (_execve(name, __DECONST(char **, argv), envp));
 }
 
 int
 execlp(const char *name, const char *arg, ...)
 {
 	va_list ap;
-	char **argv;
+	const char **argv;
 	int n;
 
 	va_start(ap, arg);
@@ -125,17 +128,15 @@
 	}
 	va_start(ap, arg);
 	n = 1;
-	argv[0] = (char *)arg;
+	argv[0] = arg;
 	while ((argv[n] = va_arg(ap, char *)) != NULL)
 		n++;
 	va_end(ap);
-	return (execvp(name, argv));
-}
-
-int
-execv(name, argv)
-	const char *name;
-	char * const *argv;
+	return (execvp(name, __DECONST(char **, argv)));
+}
+
+int
+execv(const char *name, char * const *argv)
 {
 	(void)_execve(name, argv, environ);
 	return (-1);
@@ -144,33 +145,25 @@
 int
 execvp(const char *name, char * const *argv)
 {
-	const char *path;
-
-	/* Get the path we're searching. */
-	if ((path = getenv("PATH")) == NULL)
-		path = _PATH_DEFPATH;
-
-	return (execvP(name, path, argv));
-}
-
-int
-execvP(name, path, argv)
-	const char *name;
-	const char *path;
-	char * const *argv;
-{
-	char **memp;
-	int cnt, lp, ln;
-	char *p;
+	return (_execvpe(name, argv, environ));
+}
+
+static int
+execvPe(const char *name, const char *path, char * const *argv,
+    char * const *envp)
+{
+	const char **memp;
+	size_t cnt, lp, ln;
 	int eacces, save_errno;
-	char *bp, *cur, buf[MAXPATHLEN];
+	char *cur, buf[MAXPATHLEN];
+	const char *p, *bp;
 	struct stat sb;
 
 	eacces = 0;
 
 	/* If it's an absolute or relative path name, it's easy. */
-	if (index(name, '/')) {
-		bp = (char *)name;
+	if (strchr(name, '/')) {
+		bp = name;
 		cur = NULL;
 		goto retry;
 	}
@@ -217,7 +210,7 @@
 		bcopy(name, buf + lp + 1, ln);
 		buf[lp + ln + 1] = '\0';
 
-retry:		(void)_execve(bp, argv, environ);
+retry:		(void)_execve(bp, argv, envp);
 		switch (errno) {
 		case E2BIG:
 			goto done;
@@ -228,15 +221,30 @@
 		case ENOEXEC:
 			for (cnt = 0; argv[cnt]; ++cnt)
 				;
-			memp = alloca((cnt + 2) * sizeof(char *));
+
+			/*
+			 * cnt may be 0 above; always allocate at least
+			 * 3 entries so that we can at least fit "sh", bp, and
+			 * the NULL terminator.  We can rely on cnt to take into
+			 * account the NULL terminator in all other scenarios,
+			 * as we drop argv[0].
+			 */
+			memp = alloca(MAX(3, cnt + 2) * sizeof(char *));
 			if (memp == NULL) {
 				/* errno = ENOMEM; XXX override ENOEXEC? */
 				goto done;
 			}
-			memp[0] = "sh";
-			memp[1] = bp;
-			bcopy(argv + 1, memp + 2, cnt * sizeof(char *));
-			(void)_execve(_PATH_BSHELL, memp, environ);
+			if (cnt > 0) {
+				memp[0] = argv[0];
+				memp[1] = bp;
+				bcopy(argv + 1, memp + 2, cnt * sizeof(char *));
+			} else {
+				memp[0] = "sh";
+				memp[1] = bp;
+				memp[2] = NULL;
+			}
+ 			(void)_execve(_PATH_BSHELL,
+			    __DECONST(char **, memp), envp);
 			goto done;
 		case ENOMEM:
 			goto done;
@@ -268,8 +276,27 @@
 	}
 	if (eacces)
 		errno = EACCES;
-	else
+	else if (cur)
 		errno = ENOENT;
+	/* else use existing errno from _execve */
 done:
 	return (-1);
 }
+
+int
+execvP(const char *name, const char *path, char * const argv[])
+{
+	return execvPe(name, path, argv, environ);
+}
+
+__private_extern__ int
+_execvpe(const char *name, char * const argv[], char * const envp[])
+{
+	const char *path;
+
+	/* Get the path we're searching. */
+	if ((path = getenv("PATH")) == NULL)
+		path = _PATH_DEFPATH;
+
+	return (execvPe(name, path, argv, envp));
+}