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