libc

commit 33bff38345656007e74f1cb08b9cf9cdca3f22eb
parent 9ed5a8907d9f6315a532b49df8c21d073ca1ed62
Author: evenfri <evenfri256@gmail.com>
Date:   Mon, 10 Aug 2026 02:58:32 +0800

fix: execvp

Diffstat:
M
execvp.c
 | 
19
+++++++++++--------

1 file changed, 11 insertions(+), 8 deletions(-)
diff --git a/execvp.c b/execvp.c
@@ -5,19 +5,22 @@
 
 #include "libc.h"
 
+static char *empty_env[] = { NULL };
 char **environ;
 
 int execvp(const char *file, char *const argv[]) {
+  char **env = (environ != NULL) ? environ : empty_env;
+
   if (strchr(file, '/') != 0) {
-    return execve(file, argv, environ);
+    return execve(file, argv, env);
   }
 
   const char *path_env = NULL;
-  if (environ != NULL) {
-    for (char **env = environ; *env != NULL; ++env) {
-      if (env[0][0] == 'P' && env[0][1] == 'A' && 
-          env[0][2] == 'T' && env[0][3] == 'H' && env[0][4] == '=') {
-        path_env = *env + 5;
+  if (env != NULL) {
+    for (char **ep = env; *ep != NULL; ++ep) {
+      if (ep[0][0] == 'P' && ep[0][1] == 'A' && 
+          ep[0][2] == 'T' && ep[0][3] == 'H' && ep[0][4] == '=') {
+        path_env = *ep + 5;
         break;
       }
     }
@@ -42,14 +45,14 @@ int execvp(const char *file, char *const argv[]) {
     if (dir_len == 0) {
       if (file_len + 1 < sizeof(path_buf)) {
         memcpy(path_buf, file, file_len + 1);
-        execve(path_buf, argv, environ);
+        execve(path_buf, argv, env);
       }
     } else {
       if (dir_len + 1 + file_len + 1 < sizeof(path_buf)) {
         memcpy(path_buf, start, dir_len);
         path_buf[dir_len] = '/';
         memcpy(path_buf + dir_len + 1, file, file_len + 1);
-        execve(path_buf, argv, environ);
+        execve(path_buf, argv, env);
       }
     }