Merge branch 'jk/alternate-ref-optim' into maint
[git] / builtin / diff-index.c
1 #include "cache.h"
2 #include "diff.h"
3 #include "commit.h"
4 #include "revision.h"
5 #include "builtin.h"
6 #include "submodule.h"
7
8 static const char diff_cache_usage[] =
9 "git diff-index [-m] [--cached] "
10 "[<common-diff-options>] <tree-ish> [<path>...]"
11 COMMON_DIFF_OPTIONS_HELP;
12
13 int cmd_diff_index(int argc, const char **argv, const char *prefix)
14 {
15         struct rev_info rev;
16         int cached = 0;
17         int i;
18         int result;
19
20         init_revisions(&rev, prefix);
21         gitmodules_config();
22         git_config(git_diff_basic_config, NULL); /* no "diff" UI options */
23         rev.abbrev = 0;
24         precompose_argv(argc, argv);
25
26         argc = setup_revisions(argc, argv, &rev, NULL);
27         for (i = 1; i < argc; i++) {
28                 const char *arg = argv[i];
29
30                 if (!strcmp(arg, "--cached"))
31                         cached = 1;
32                 else
33                         usage(diff_cache_usage);
34         }
35         if (!rev.diffopt.output_format)
36                 rev.diffopt.output_format = DIFF_FORMAT_RAW;
37
38         /*
39          * Make sure there is one revision (i.e. pending object),
40          * and there is no revision filtering parameters.
41          */
42         if (rev.pending.nr != 1 ||
43             rev.max_count != -1 || rev.min_age != -1 || rev.max_age != -1)
44                 usage(diff_cache_usage);
45         if (!cached) {
46                 setup_work_tree();
47                 if (read_cache_preload(&rev.diffopt.pathspec) < 0) {
48                         perror("read_cache_preload");
49                         return -1;
50                 }
51         } else if (read_cache() < 0) {
52                 perror("read_cache");
53                 return -1;
54         }
55         result = run_diff_index(&rev, cached);
56         return diff_result_code(&rev.diffopt, result);
57 }