git-send-email: Add --thread option
[git/aroben.git] / lockfile.c
blob5ad2858b4885022141d915fa0555c51f80d11c1c
1 /*
2 * Copyright (c) 2005, Junio C Hamano
3 */
4 #include "cache.h"
6 static struct lock_file *lock_file_list;
7 static const char *alternate_index_output;
9 static void remove_lock_file(void)
11 pid_t me = getpid();
13 while (lock_file_list) {
14 if (lock_file_list->owner == me &&
15 lock_file_list->filename[0])
16 unlink(lock_file_list->filename);
17 lock_file_list = lock_file_list->next;
21 static void remove_lock_file_on_signal(int signo)
23 remove_lock_file();
24 signal(SIGINT, SIG_DFL);
25 raise(signo);
28 static int lock_file(struct lock_file *lk, const char *path)
30 int fd;
31 sprintf(lk->filename, "%s.lock", path);
32 fd = open(lk->filename, O_RDWR | O_CREAT | O_EXCL, 0666);
33 if (0 <= fd) {
34 lk->owner = getpid();
35 if (!lk->on_list) {
36 lk->next = lock_file_list;
37 lock_file_list = lk;
38 lk->on_list = 1;
40 if (lock_file_list) {
41 signal(SIGINT, remove_lock_file_on_signal);
42 atexit(remove_lock_file);
44 if (adjust_shared_perm(lk->filename))
45 return error("cannot fix permission bits on %s",
46 lk->filename);
48 else
49 lk->filename[0] = 0;
50 return fd;
53 int hold_lock_file_for_update(struct lock_file *lk, const char *path, int die_on_error)
55 int fd = lock_file(lk, path);
56 if (fd < 0 && die_on_error)
57 die("unable to create '%s.lock': %s", path, strerror(errno));
58 return fd;
61 int commit_lock_file(struct lock_file *lk)
63 char result_file[PATH_MAX];
64 int i;
65 strcpy(result_file, lk->filename);
66 i = strlen(result_file) - 5; /* .lock */
67 result_file[i] = 0;
68 i = rename(lk->filename, result_file);
69 lk->filename[0] = 0;
70 return i;
73 int hold_locked_index(struct lock_file *lk, int die_on_error)
75 return hold_lock_file_for_update(lk, get_index_file(), die_on_error);
78 void set_alternate_index_output(const char *name)
80 alternate_index_output = name;
83 int commit_locked_index(struct lock_file *lk)
85 if (alternate_index_output) {
86 int result = rename(lk->filename, alternate_index_output);
87 lk->filename[0] = 0;
88 return result;
90 else
91 return commit_lock_file(lk);
94 void rollback_lock_file(struct lock_file *lk)
96 if (lk->filename[0])
97 unlink(lk->filename);
98 lk->filename[0] = 0;