Fix 'git add' with .gitignore
[git] / lockfile.c
1 /*
2  * Copyright (c) 2005, Junio C Hamano
3  */
4 #include "cache.h"
5
6 static struct lock_file *lock_file_list;
7
8 static void remove_lock_file(void)
9 {
10         while (lock_file_list) {
11                 if (lock_file_list->filename[0])
12                         unlink(lock_file_list->filename);
13                 lock_file_list = lock_file_list->next;
14         }
15 }
16
17 static void remove_lock_file_on_signal(int signo)
18 {
19         remove_lock_file();
20         signal(SIGINT, SIG_DFL);
21         raise(signo);
22 }
23
24 static int lock_file(struct lock_file *lk, const char *path)
25 {
26         int fd;
27         sprintf(lk->filename, "%s.lock", path);
28         fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
29         if (0 <= fd) {
30                 if (!lk->next) {
31                         lk->next = lock_file_list;
32                         lock_file_list = lk;
33                         signal(SIGINT, remove_lock_file_on_signal);
34                         atexit(remove_lock_file);
35                 }
36                 if (adjust_shared_perm(lk->filename))
37                         return error("cannot fix permission bits on %s",
38                                      lk->filename);
39         }
40         return fd;
41 }
42
43 int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
44 {
45         int fd = lock_file(lk, path);
46         if (fd < 0 && die_on_error)
47                 die("unable to create '%s': %s", path, strerror(errno));
48         return fd;
49 }
50
51 int commit_lock_file(struct lock_file *lk)
52 {
53         char result_file[PATH_MAX];
54         int i;
55         strcpy(result_file, lk->filename);
56         i = strlen(result_file) - 5; /* .lock */
57         result_file[i] = 0;
58         i = rename(lk->filename, result_file);
59         lk->filename[0] = 0;
60         return i;
61 }
62
63 void rollback_lock_file(struct lock_file *lk)
64 {
65         if (lk->filename[0])
66                 unlink(lk->filename);
67         lk->filename[0] = 0;
68 }
69