xdiff-merge: optionally show conflicts in "diff3 -m" style
[git] / builtin-merge-file.c
1 #include "builtin.h"
2 #include "cache.h"
3 #include "xdiff/xdiff.h"
4 #include "xdiff-interface.h"
5
6 static const char merge_file_usage[] =
7 "git merge-file [-p | --stdout] [--diff3] [-q | --quiet] [-L name1 [-L orig [-L name2]]] file1 orig_file file2";
8
9 int cmd_merge_file(int argc, const char **argv, const char *prefix)
10 {
11         const char *names[3];
12         mmfile_t mmfs[3];
13         mmbuffer_t result = {NULL, 0};
14         xpparam_t xpp = {XDF_NEED_MINIMAL};
15         int ret = 0, i = 0, to_stdout = 0;
16         int merge_level = XDL_MERGE_ZEALOUS_ALNUM;
17         int merge_style = 0;
18
19         while (argc > 4) {
20                 if (!strcmp(argv[1], "-L") && i < 3) {
21                         names[i++] = argv[2];
22                         argc--;
23                         argv++;
24                 } else if (!strcmp(argv[1], "-p") ||
25                                 !strcmp(argv[1], "--stdout"))
26                         to_stdout = 1;
27                 else if (!strcmp(argv[1], "-q") ||
28                                 !strcmp(argv[1], "--quiet"))
29                         freopen("/dev/null", "w", stderr);
30                 else if (!strcmp(argv[1], "--diff3")) {
31                         merge_style = XDL_MERGE_DIFF3;
32                         merge_level = XDL_MERGE_EAGER;
33                 }
34                 else
35                         usage(merge_file_usage);
36                 argc--;
37                 argv++;
38         }
39
40         if (argc != 4)
41                 usage(merge_file_usage);
42
43         for (; i < 3; i++)
44                 names[i] = argv[i + 1];
45
46         for (i = 0; i < 3; i++) {
47                 if (read_mmfile(mmfs + i, argv[i + 1]))
48                         return -1;
49                 if (buffer_is_binary(mmfs[i].ptr, mmfs[i].size))
50                         return error("Cannot merge binary files: %s\n",
51                                         argv[i + 1]);
52         }
53
54         ret = xdl_merge(mmfs + 1, mmfs + 0, names[0], mmfs + 2, names[2],
55                         &xpp, merge_level | merge_style, &result);
56
57         for (i = 0; i < 3; i++)
58                 free(mmfs[i].ptr);
59
60         if (ret >= 0) {
61                 const char *filename = argv[1];
62                 FILE *f = to_stdout ? stdout : fopen(filename, "wb");
63
64                 if (!f)
65                         ret = error("Could not open %s for writing", filename);
66                 else if (result.size &&
67                          fwrite(result.ptr, result.size, 1, f) != 1)
68                         ret = error("Could not write to %s", filename);
69                 else if (fclose(f))
70                         ret = error("Could not close %s", filename);
71                 free(result.ptr);
72         }
73
74         return ret;
75 }