builtin/merge-file.c

   1 #define USE_THE_REPOSITORY_VARIABLE
   2 #include "builtin.h"
   3 #include "abspath.h"
   4 #include "diff.h"
   5 #include "hex.h"
   6 #include "object-name.h"
   7 #include "object-store.h"
   8 #include "config.h"
   9 #include "gettext.h"
  10 #include "setup.h"
  11 #include "xdiff/xdiff.h"
  12 #include "xdiff-interface.h"
  13 #include "parse-options.h"
  14
  15 static const char *const merge_file_usage[] = {
  16         N_("git merge-file [<options>] [-L <name1> [-L <orig> [-L <name2>]]] <file1> <orig-file> <file2>"),
  17         NULL
  18 };
  19
  20 static int label_cb(const struct option *opt, const char *arg, int unset)
  21 {
  22         static int label_count = 0;
  23         const char **names = (const char **)opt->value;
  24
  25         BUG_ON_OPT_NEG(unset);
  26
  27         if (label_count >= 3)
  28                 return error("too many labels on the command line");
  29         names[label_count++] = arg;
  30         return 0;
  31 }
  32
  33 static int set_diff_algorithm(xpparam_t *xpp,
  34                               const char *alg)
  35 {
  36         long diff_algorithm = parse_algorithm_value(alg);
  37         if (diff_algorithm < 0)
  38                 return -1;
  39         xpp->flags = (xpp->flags & ~XDF_DIFF_ALGORITHM_MASK) | diff_algorithm;
  40         return 0;
  41 }
  42
  43 static int diff_algorithm_cb(const struct option *opt,
  44                                 const char *arg, int unset)
  45 {
  46         xpparam_t *xpp = opt->value;
  47
  48         BUG_ON_OPT_NEG(unset);
  49
  50         if (set_diff_algorithm(xpp, arg))
  51                 return error(_("option diff-algorithm accepts \"myers\", "
  52                                "\"minimal\", \"patience\" and \"histogram\""));
  53
  54         return 0;
  55 }
  56
  57 int cmd_merge_file(int argc,
  58                    const char **argv,
  59                    const char *prefix,
  60                    struct repository *repo UNUSED)
  61 {
  62         const char *names[3] = { 0 };
  63         mmfile_t mmfs[3] = { 0 };
  64         mmbuffer_t result = { 0 };
  65         xmparam_t xmp = { 0 };
  66         int ret = 0, i = 0, to_stdout = 0, object_id = 0;
  67         int quiet = 0;
  68         struct option options[] = {
  69                 OPT_BOOL('p', "stdout", &to_stdout, N_("send results to standard output")),
  70                 OPT_BOOL(0,   "object-id", &object_id, N_("use object IDs instead of filenames")),
  71                 OPT_SET_INT(0, "diff3", &xmp.style, N_("use a diff3 based merge"), XDL_MERGE_DIFF3),
  72                 OPT_SET_INT(0, "zdiff3", &xmp.style, N_("use a zealous diff3 based merge"),
  73                                 XDL_MERGE_ZEALOUS_DIFF3),
  74                 OPT_SET_INT(0, "ours", &xmp.favor, N_("for conflicts, use our version"),
  75                             XDL_MERGE_FAVOR_OURS),
  76                 OPT_SET_INT(0, "theirs", &xmp.favor, N_("for conflicts, use their version"),
  77                             XDL_MERGE_FAVOR_THEIRS),
  78                 OPT_SET_INT(0, "union", &xmp.favor, N_("for conflicts, use a union version"),
  79                             XDL_MERGE_FAVOR_UNION),
  80                 OPT_CALLBACK_F(0, "diff-algorithm", &xmp.xpp, N_("<algorithm>"),
  81                              N_("choose a diff algorithm"),
  82                              PARSE_OPT_NONEG, diff_algorithm_cb),
  83                 OPT_INTEGER(0, "marker-size", &xmp.marker_size,
  84                             N_("for conflicts, use this marker size")),
  85                 OPT__QUIET(&quiet, N_("do not warn about conflicts")),
  86                 OPT_CALLBACK('L', NULL, names, N_("name"),
  87                              N_("set labels for file1/orig-file/file2"), &label_cb),
  88                 OPT_END(),
  89         };
  90
  91         xmp.level = XDL_MERGE_ZEALOUS_ALNUM;
  92         xmp.style = 0;
  93         xmp.favor = 0;
  94
  95         if (startup_info->have_repository) {
  96                 /* Read the configuration file */
  97                 git_config(git_xmerge_config, NULL);
  98                 if (0 <= git_xmerge_style)
  99                         xmp.style = git_xmerge_style;
 100         }
 101
 102         argc = parse_options(argc, argv, prefix, options, merge_file_usage, 0);
 103         if (argc != 3)
 104                 usage_with_options(merge_file_usage, options);
 105         if (quiet) {
 106                 if (!freopen("/dev/null", "w", stderr))
 107                         return error_errno("failed to redirect stderr to /dev/null");
 108         }
 109
 110         if (object_id)
 111                 setup_git_directory();
 112
 113         for (i = 0; i < 3; i++) {
 114                 char *fname;
 115                 struct object_id oid;
 116                 mmfile_t *mmf = mmfs + i;
 117
 118                 if (!names[i])
 119                         names[i] = argv[i];
 120
 121                 fname = prefix_filename(prefix, argv[i]);
 122
 123                 if (object_id) {
 124                         if (repo_get_oid(the_repository, argv[i], &oid))
 125                                 ret = error(_("object '%s' does not exist"),
 126                                               argv[i]);
 127                         else if (!oideq(&oid, the_hash_algo->empty_blob))
 128                                 read_mmblob(mmf, &oid);
 129                         else
 130                                 read_mmfile(mmf, "/dev/null");
 131                 } else if (read_mmfile(mmf, fname)) {
 132                         ret = -1;
 133                 }
 134                 if (ret != -1 && (mmf->size > MAX_XDIFF_SIZE ||
 135                     buffer_is_binary(mmf->ptr, mmf->size))) {
 136                         ret = error("Cannot merge binary files: %s",
 137                                     argv[i]);
 138                 }
 139
 140                 free(fname);
 141                 if (ret)
 142                         goto cleanup;
 143
 144         }
 145
 146         xmp.ancestor = names[1];
 147         xmp.file1 = names[0];
 148         xmp.file2 = names[2];
 149         ret = xdl_merge(mmfs + 1, mmfs + 0, mmfs + 2, &xmp, &result);
 150
 151         if (ret >= 0) {
 152                 if (object_id && !to_stdout) {
 153                         struct object_id oid;
 154                         if (result.size) {
 155                                 if (write_object_file(result.ptr, result.size, OBJ_BLOB, &oid) < 0)
 156                                         ret = error(_("Could not write object file"));
 157                         } else {
 158                                 oidcpy(&oid, the_hash_algo->empty_blob);
 159                         }
 160                         if (ret >= 0)
 161                                 printf("%s\n", oid_to_hex(&oid));
 162                 } else {
 163                         const char *filename = argv[0];
 164                         char *fpath = prefix_filename(prefix, argv[0]);
 165                         FILE *f = to_stdout ? stdout : fopen(fpath, "wb");
 166
 167                         if (!f)
 168                                 ret = error_errno("Could not open %s for writing",
 169                                                   filename);
 170                         else if (result.size &&
 171                                  fwrite(result.ptr, result.size, 1, f) != 1)
 172                                 ret = error_errno("Could not write to %s", filename);
 173                         else if (fclose(f))
 174                                 ret = error_errno("Could not close %s", filename);
 175                         free(fpath);
 176                 }
 177                 free(result.ptr);
 178         }
 179
 180         if (ret > 127)
 181                 ret = 127;
 182
 183 cleanup:
 184         for (i = 0; i < 3; i++)
 185                 free(mmfs[i].ptr);
 186
 187         return ret;
 188 }