Teach update-ref about a symbolic ref stored in a textfile.
[git.git] / checkout-index.c
1 /*
2  * Check-out files from the "current cache directory"
3  *
4  * Copyright (C) 2005 Linus Torvalds
5  *
6  * Careful: order of argument flags does matter. For example,
7  *
8  *      git-checkout-index -a -f file.c
9  *
10  * Will first check out all files listed in the cache (but not
11  * overwrite any old ones), and then force-checkout "file.c" a
12  * second time (ie that one _will_ overwrite any old contents
13  * with the same filename).
14  *
15  * Also, just doing "git-checkout-index" does nothing. You probably
16  * meant "git-checkout-index -a". And if you want to force it, you
17  * want "git-checkout-index -f -a".
18  *
19  * Intuitiveness is not the goal here. Repeatability is. The
20  * reason for the "no arguments means no work" thing is that
21  * from scripts you are supposed to be able to do things like
22  *
23  *      find . -name '*.h' -print0 | xargs -0 git-checkout-index -f --
24  *
25  * which will force all existing *.h files to be replaced with
26  * their cached copies. If an empty command line implied "all",
27  * then this would force-refresh everything in the cache, which
28  * was not the point.
29  *
30  * Oh, and the "--" is just a good idea when you know the rest
31  * will be filenames. Just so that you wouldn't have a filename
32  * of "-a" causing problems (not possible in the above example,
33  * but get used to it in scripting!).
34  */
35 #include "cache.h"
36
37 static struct checkout state = {
38         .base_dir = "",
39         .base_dir_len = 0,
40         .force = 0,
41         .quiet = 0,
42         .not_new = 0,
43         .refresh_cache = 0,
44 };
45
46 static int checkout_file(const char *name)
47 {
48         int pos = cache_name_pos(name, strlen(name));
49         if (pos < 0) {
50                 if (!state.quiet) {
51                         pos = -pos - 1;
52                         fprintf(stderr,
53                                 "git-checkout-index: %s is %s.\n",
54                                 name,
55                                 (pos < active_nr &&
56                                  !strcmp(active_cache[pos]->name, name)) ?
57                                 "unmerged" : "not in the cache");
58                 }
59                 return -1;
60         }
61         return checkout_entry(active_cache[pos], &state);
62 }
63
64 static int checkout_all(void)
65 {
66         int i;
67
68         for (i = 0; i < active_nr ; i++) {
69                 struct cache_entry *ce = active_cache[i];
70                 if (ce_stage(ce))
71                         continue;
72                 if (checkout_entry(ce, &state) < 0)
73                         return -1;
74         }
75         return 0;
76 }
77
78 static const char checkout_cache_usage[] =
79 "git-checkout-index [-u] [-q] [-a] [-f] [-n] [--prefix=<string>] [--] <file>...";
80
81 static struct cache_file cache_file;
82
83 int main(int argc, char **argv)
84 {
85         int i, force_filename = 0;
86         int newfd = -1;
87
88         if (read_cache() < 0) {
89                 die("invalid cache");
90         }
91
92         for (i = 1; i < argc; i++) {
93                 const char *arg = argv[i];
94                 if (!force_filename) {
95                         if (!strcmp(arg, "-a")) {
96                                 checkout_all();
97                                 continue;
98                         }
99                         if (!strcmp(arg, "--")) {
100                                 force_filename = 1;
101                                 continue;
102                         }
103                         if (!strcmp(arg, "-f")) {
104                                 state.force = 1;
105                                 continue;
106                         }
107                         if (!strcmp(arg, "-q")) {
108                                 state.quiet = 1;
109                                 continue;
110                         }
111                         if (!strcmp(arg, "-n")) {
112                                 state.not_new = 1;
113                                 continue;
114                         }
115                         if (!strcmp(arg, "-u")) {
116                                 state.refresh_cache = 1;
117                                 if (newfd < 0)
118                                         newfd = hold_index_file_for_update
119                                                 (&cache_file,
120                                                  get_index_file());
121                                 if (newfd < 0)
122                                         die("cannot open index.lock file.");
123                                 continue;
124                         }
125                         if (!memcmp(arg, "--prefix=", 9)) {
126                                 state.base_dir = arg+9;
127                                 state.base_dir_len = strlen(state.base_dir);
128                                 continue;
129                         }
130                         if (arg[0] == '-')
131                                 usage(checkout_cache_usage);
132                 }
133                 if (state.base_dir_len) {
134                         /* when --prefix is specified we do not
135                          * want to update cache.
136                          */
137                         if (state.refresh_cache) {
138                                 close(newfd); newfd = -1;
139                                 rollback_index_file(&cache_file);
140                         }
141                         state.refresh_cache = 0;
142                 }
143                 checkout_file(arg);
144         }
145
146         if (0 <= newfd &&
147             (write_cache(newfd, active_cache, active_nr) ||
148              commit_index_file(&cache_file)))
149                 die("Unable to write new cachefile");
150         return 0;
151 }