diff-cache.c

   1 #include "cache.h"
   2 #include "diff.h"
   3
   4 static int cached_only = 0;
   5 static int diff_output_format = DIFF_FORMAT_RAW;
   6 static int diff_line_termination = '\n';
   7 static int match_nonexisting = 0;
   8 static int detect_rename = 0;
   9 static int find_copies_harder = 0;
  10 static int diff_setup_opt = 0;
  11 static int diff_score_opt = 0;
  12 static const char *pickaxe = NULL;
  13 static int pickaxe_opts = 0;
  14 static int diff_break_opt = -1;
  15 static const char *orderfile = NULL;
  16 static const char *diff_filter = NULL;
  17
  18 /* A file entry went away or appeared */
  19 static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
  20 {
  21         diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
  22 }
  23
  24 static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
  25 {
  26         unsigned char *sha1 = ce->sha1;
  27         unsigned int mode = ce->ce_mode;
  28
  29         if (!cached_only) {
  30                 static unsigned char no_sha1[20];
  31                 int changed;
  32                 struct stat st;
  33                 if (lstat(ce->name, &st) < 0) {
  34                         if (errno == ENOENT && match_nonexisting) {
  35                                 *sha1p = sha1;
  36                                 *modep = mode;
  37                                 return 0;
  38                         }
  39                         return -1;
  40                 }
  41                 changed = ce_match_stat(ce, &st);
  42                 if (changed) {
  43                         mode = create_ce_mode(st.st_mode);
  44                         sha1 = no_sha1;
  45                 }
  46         }
  47
  48         *sha1p = sha1;
  49         *modep = mode;
  50         return 0;
  51 }
  52
  53 static void show_new_file(struct cache_entry *new)
  54 {
  55         unsigned char *sha1;
  56         unsigned int mode;
  57
  58         /* New file in the index: it might actually be different in the working copy */
  59         if (get_stat_data(new, &sha1, &mode) < 0)
  60                 return;
  61
  62         show_file("+", new, sha1, mode);
  63 }
  64
  65 static int show_modified(struct cache_entry *old,
  66                          struct cache_entry *new,
  67                          int report_missing)
  68 {
  69         unsigned int mode, oldmode;
  70         unsigned char *sha1;
  71
  72         if (get_stat_data(new, &sha1, &mode) < 0) {
  73                 if (report_missing)
  74                         show_file("-", old, old->sha1, old->ce_mode);
  75                 return -1;
  76         }
  77
  78         oldmode = old->ce_mode;
  79         if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
  80             !find_copies_harder)
  81                 return 0;
  82
  83         mode = ntohl(mode);
  84         oldmode = ntohl(oldmode);
  85
  86         diff_change(oldmode, mode,
  87                     old->sha1, sha1, old->name, NULL);
  88         return 0;
  89 }
  90
  91 static int diff_cache(struct cache_entry **ac, int entries, const char **pathspec)
  92 {
  93         while (entries) {
  94                 struct cache_entry *ce = *ac;
  95                 int same = (entries > 1) && ce_same_name(ce, ac[1]);
  96
  97                 if (!ce_path_match(ce, pathspec))
  98                         goto skip_entry;
  99
 100                 switch (ce_stage(ce)) {
 101                 case 0:
 102                         /* No stage 1 entry? That means it's a new file */
 103                         if (!same) {
 104                                 show_new_file(ce);
 105                                 break;
 106                         }
 107                         /* Show difference between old and new */
 108                         show_modified(ac[1], ce, 1);
 109                         break;
 110                 case 1:
 111                         /* No stage 3 (merge) entry? That means it's been deleted */
 112                         if (!same) {
 113                                 show_file("-", ce, ce->sha1, ce->ce_mode);
 114                                 break;
 115                         }
 116                         /* We come here with ce pointing at stage 1
 117                          * (original tree) and ac[1] pointing at stage
 118                          * 3 (unmerged).  show-modified with
 119                          * report-mising set to false does not say the
 120                          * file is deleted but reports true if work
 121                          * tree does not have it, in which case we
 122                          * fall through to report the unmerged state.
 123                          * Otherwise, we show the differences between
 124                          * the original tree and the work tree.
 125                          */
 126                         if (!cached_only && !show_modified(ce, ac[1], 0))
 127                                 break;
 128                         /* fallthru */
 129                 case 3:
 130                         diff_unmerge(ce->name);
 131                         break;
 132
 133                 default:
 134                         die("impossible cache entry stage");
 135                 }
 136
 137 skip_entry:
 138                 /*
 139                  * Ignore all the different stages for this file,
 140                  * we've handled the relevant cases now.
 141                  */
 142                 do {
 143                         ac++;
 144                         entries--;
 145                 } while (entries && ce_same_name(ce, ac[0]));
 146         }
 147         return 0;
 148 }
 149
 150 /*
 151  * This turns all merge entries into "stage 3". That guarantees that
 152  * when we read in the new tree (into "stage 1"), we won't lose sight
 153  * of the fact that we had unmerged entries.
 154  */
 155 static void mark_merge_entries(void)
 156 {
 157         int i;
 158         for (i = 0; i < active_nr; i++) {
 159                 struct cache_entry *ce = active_cache[i];
 160                 if (!ce_stage(ce))
 161                         continue;
 162                 ce->ce_flags |= htons(CE_STAGEMASK);
 163         }
 164 }
 165
 166 static const char diff_cache_usage[] =
 167 "git-diff-cache [-m] [--cached] "
 168 "[<common diff options>] <tree-ish> [<path>...]"
 169 COMMON_DIFF_OPTIONS_HELP;
 170
 171 int main(int argc, char **argv)
 172 {
 173         const char *tree_name = NULL;
 174         unsigned char sha1[20];
 175         const char *prefix = setup_git_directory();
 176         const char **pathspec = NULL;
 177         void *tree;
 178         unsigned long size;
 179         int ret;
 180         int allow_options = 1;
 181         int i;
 182
 183         for (i = 1; i < argc; i++) {
 184                 const char *arg = argv[i];
 185
 186                 if (!allow_options || *arg != '-') {
 187                         if (tree_name)
 188                                 break;
 189                         tree_name = arg;
 190                         continue;
 191                 }
 192
 193                 if (!strcmp(arg, "--")) {
 194                         allow_options = 0;
 195                         continue;
 196                 }
 197                 if (!strcmp(arg, "-r")) {
 198                         /* We accept the -r flag just to look like git-diff-tree */
 199                         continue;
 200                 }
 201                 /* We accept the -u flag as a synonym for "-p" */
 202                 if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
 203                         diff_output_format = DIFF_FORMAT_PATCH;
 204                         continue;
 205                 }
 206                 if (!strncmp(arg, "-B", 2)) {
 207                         if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
 208                                 usage(diff_cache_usage);
 209                         continue;
 210                 }
 211                 if (!strncmp(arg, "-M", 2)) {
 212                         detect_rename = DIFF_DETECT_RENAME;
 213                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 214                                 usage(diff_cache_usage);
 215                         continue;
 216                 }
 217                 if (!strncmp(arg, "-C", 2)) {
 218                         detect_rename = DIFF_DETECT_COPY;
 219                         if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 220                                 usage(diff_cache_usage);
 221                         continue;
 222                 }
 223                 if (!strcmp(arg, "--find-copies-harder")) {
 224                         find_copies_harder = 1;
 225                         continue;
 226                 }
 227                 if (!strcmp(arg, "-z")) {
 228                         diff_line_termination = 0;
 229                         continue;
 230                 }
 231                 if (!strcmp(arg, "--name-only")) {
 232                         diff_output_format = DIFF_FORMAT_NAME;
 233                         continue;
 234                 }
 235                 if (!strcmp(arg, "-R")) {
 236                         diff_setup_opt |= DIFF_SETUP_REVERSE;
 237                         continue;
 238                 }
 239                 if (!strncmp(arg, "-S", 2)) {
 240                         pickaxe = arg + 2;
 241                         continue;
 242                 }
 243                 if (!strncmp(arg, "--diff-filter=", 14)) {
 244                         diff_filter = arg + 14;
 245                         continue;
 246                 }
 247                 if (!strncmp(arg, "-O", 2)) {
 248                         orderfile = arg + 2;
 249                         continue;
 250                 }
 251                 if (!strcmp(arg, "--pickaxe-all")) {
 252                         pickaxe_opts = DIFF_PICKAXE_ALL;
 253                         continue;
 254                 }
 255                 if (!strcmp(arg, "-m")) {
 256                         match_nonexisting = 1;
 257                         continue;
 258                 }
 259                 if (!strcmp(arg, "--cached")) {
 260                         cached_only = 1;
 261                         continue;
 262                 }
 263                 usage(diff_cache_usage);
 264         }
 265
 266         pathspec = get_pathspec(prefix, argv + i);
 267
 268         if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 269                 usage(diff_cache_usage);
 270
 271         if (!tree_name || get_sha1(tree_name, sha1))
 272                 usage(diff_cache_usage);
 273
 274         read_cache();
 275
 276         /* The rest is for paths restriction. */
 277         diff_setup(diff_setup_opt);
 278
 279         mark_merge_entries();
 280
 281         tree = read_object_with_reference(sha1, "tree", &size, NULL);
 282         if (!tree)
 283                 die("bad tree object %s", tree_name);
 284         if (read_tree(tree, size, 1, pathspec))
 285                 die("unable to read tree object %s", tree_name);
 286
 287         ret = diff_cache(active_cache, active_nr, pathspec);
 288
 289         diffcore_std(pathspec,
 290                      detect_rename, diff_score_opt,
 291                      pickaxe, pickaxe_opts,
 292                      diff_break_opt,
 293                      orderfile, diff_filter);
 294         diff_flush(diff_output_format, diff_line_termination);
 295         return ret;
 296 }