1 #include <stdlib.h>
2 #include <string.h>
3 #include <unistd.h>
4 #include <errno.h>
5 #include <limits.h>
6
7 extern char **__environ;
8
__execvpe(const char * file,char * const argv[],char * const envp[])9 int __execvpe(const char *file, char *const argv[], char *const envp[])
10 {
11 const char *p, *z, *path = getenv("PATH");
12 size_t l, k;
13 int seen_eacces = 0;
14
15 errno = ENOENT;
16 if (!*file) return -1;
17
18 if (strchr(file, '/'))
19 return execve(file, argv, envp);
20
21 if (!path) path = "/usr/local/bin:/bin:/usr/bin";
22 k = strnlen(file, NAME_MAX+1);
23 if (k > NAME_MAX) {
24 errno = ENAMETOOLONG;
25 return -1;
26 }
27 l = strnlen(path, PATH_MAX-1)+1;
28
29 for(p=path; ; p=z) {
30 char b[l+k+1];
31 z = __strchrnul(p, ':');
32 if (z-p >= l) {
33 if (!*z++) break;
34 continue;
35 }
36 memcpy(b, p, z-p);
37 b[z-p] = '/';
38 memcpy(b+(z-p)+(z>p), file, k+1);
39 execve(b, argv, envp);
40 switch (errno) {
41 case EACCES:
42 seen_eacces = 1;
43 case ENOENT:
44 case ENOTDIR:
45 break;
46 default:
47 return -1;
48 }
49 if (!*z++) break;
50 }
51 if (seen_eacces) errno = EACCES;
52 return -1;
53 }
54
execvp(const char * file,char * const argv[])55 int execvp(const char *file, char *const argv[])
56 {
57 return __execvpe(file, argv, __environ);
58 }
59
60 weak_alias(__execvpe, execvpe);
61