Merge branch 'lt/dirwalk' into next
[git] / exec_cmd.c
1 #include "cache.h"
2 #include "exec_cmd.h"
3 #define MAX_ARGS        32
4
5 extern char **environ;
6 static const char *builtin_exec_path = GIT_EXEC_PATH;
7 static const char *current_exec_path = NULL;
8
9 void git_set_exec_path(const char *exec_path)
10 {
11         current_exec_path = exec_path;
12 }
13
14
15 /* Returns the highest-priority, location to look for git programs. */
16 const char *git_exec_path(void)
17 {
18         const char *env;
19
20         if (current_exec_path)
21                 return current_exec_path;
22
23         env = getenv("GIT_EXEC_PATH");
24         if (env) {
25                 return env;
26         }
27
28         return builtin_exec_path;
29 }
30
31
32 int execv_git_cmd(const char **argv)
33 {
34         char git_command[PATH_MAX + 1];
35         int len,  i;
36         const char *paths[] = { current_exec_path,
37                                 getenv("GIT_EXEC_PATH"),
38                                 builtin_exec_path };
39
40         for (i = 0; i < ARRAY_SIZE(paths); ++i) {
41                 const char *exec_dir = paths[i];
42                 const char *tmp;
43
44                 if (!exec_dir) continue;
45
46                 if (*exec_dir != '/') {
47                         if (!getcwd(git_command, sizeof(git_command))) {
48                                 fprintf(stderr, "git: cannot determine "
49                                         "current directory\n");
50                                 exit(1);
51                         }
52                         len = strlen(git_command);
53
54                         /* Trivial cleanup */
55                         while (!strncmp(exec_dir, "./", 2)) {
56                                 exec_dir += 2;
57                                 while (*exec_dir == '/')
58                                         exec_dir++;
59                         }
60                         snprintf(git_command + len, sizeof(git_command) - len,
61                                  "/%s", exec_dir);
62                 } else {
63                         strcpy(git_command, exec_dir);
64                 }
65
66                 len = strlen(git_command);
67                 len += snprintf(git_command + len, sizeof(git_command) - len,
68                                 "/git-%s", argv[0]);
69
70                 if (sizeof(git_command) <= len) {
71                         fprintf(stderr,
72                                 "git: command name given is too long.\n");
73                         break;
74                 }
75
76                 /* argv[0] must be the git command, but the argv array
77                  * belongs to the caller, and my be reused in
78                  * subsequent loop iterations. Save argv[0] and
79                  * restore it on error.
80                  */
81
82                 tmp = argv[0];
83                 argv[0] = git_command;
84
85                 /* execve() can only ever return if it fails */
86                 execve(git_command, (char **)argv, environ);
87
88                 argv[0] = tmp;
89         }
90         return -1;
91
92 }
93
94
95 int execl_git_cmd(const char *cmd,...)
96 {
97         int argc;
98         const char *argv[MAX_ARGS + 1];
99         const char *arg;
100         va_list param;
101
102         va_start(param, cmd);
103         argv[0] = cmd;
104         argc = 1;
105         while (argc < MAX_ARGS) {
106                 arg = argv[argc++] = va_arg(param, char *);
107                 if (!arg)
108                         break;
109         }
110         va_end(param);
111         if (MAX_ARGS <= argc)
112                 return error("too many args to run %s", cmd);
113
114         argv[argc] = NULL;
115         return execv_git_cmd(argv);
116 }