Andrew's git / gitweb.git / diff-cache.c
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diff-cache.con commit git-rev-parse: parse ".." before simple SHA1's (800644c)
   1#include "cache.h"
   2#include "diff.h"
   3
   4static int cached_only = 0;
   5static int diff_output_format = DIFF_FORMAT_HUMAN;
   6static int match_nonexisting = 0;
   7static int detect_rename = 0;
   8static int find_copies_harder = 0;
   9static int diff_setup_opt = 0;
  10static int diff_score_opt = 0;
  11static const char *pickaxe = NULL;
  12static int pickaxe_opts = 0;
  13static int diff_break_opt = -1;
  14static const char *orderfile = NULL;
  15static const char *diff_filter = NULL;
  16
  17/* A file entry went away or appeared */
  18static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
  19{
  20        diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
  21}
  22
  23static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
  24{
  25        unsigned char *sha1 = ce->sha1;
  26        unsigned int mode = ce->ce_mode;
  27
  28        if (!cached_only) {
  29                static unsigned char no_sha1[20];
  30                int changed;
  31                struct stat st;
  32                if (lstat(ce->name, &st) < 0) {
  33                        if (errno == ENOENT && match_nonexisting) {
  34                                *sha1p = sha1;
  35                                *modep = mode;
  36                                return 0;
  37                        }
  38                        return -1;
  39                }
  40                changed = ce_match_stat(ce, &st);
  41                if (changed) {
  42                        mode = create_ce_mode(st.st_mode);
  43                        sha1 = no_sha1;
  44                }
  45        }
  46
  47        *sha1p = sha1;
  48        *modep = mode;
  49        return 0;
  50}
  51
  52static void show_new_file(struct cache_entry *new)
  53{
  54        unsigned char *sha1;
  55        unsigned int mode;
  56
  57        /* New file in the index: it might actually be different in the working copy */
  58        if (get_stat_data(new, &sha1, &mode) < 0)
  59                return;
  60
  61        show_file("+", new, sha1, mode);
  62}
  63
  64static int show_modified(struct cache_entry *old,
  65                         struct cache_entry *new,
  66                         int report_missing)
  67{
  68        unsigned int mode, oldmode;
  69        unsigned char *sha1;
  70
  71        if (get_stat_data(new, &sha1, &mode) < 0) {
  72                if (report_missing)
  73                        show_file("-", old, old->sha1, old->ce_mode);
  74                return -1;
  75        }
  76
  77        oldmode = old->ce_mode;
  78        if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
  79            !find_copies_harder)
  80                return 0;
  81
  82        mode = ntohl(mode);
  83        oldmode = ntohl(oldmode);
  84
  85        diff_change(oldmode, mode,
  86                    old->sha1, sha1, old->name, NULL);
  87        return 0;
  88}
  89
  90static int diff_cache(struct cache_entry **ac, int entries)
  91{
  92        while (entries) {
  93                struct cache_entry *ce = *ac;
  94                int same = (entries > 1) && ce_same_name(ce, ac[1]);
  95
  96                switch (ce_stage(ce)) {
  97                case 0:
  98                        /* No stage 1 entry? That means it's a new file */
  99                        if (!same) {
 100                                show_new_file(ce);
 101                                break;
 102                        }
 103                        /* Show difference between old and new */
 104                        show_modified(ac[1], ce, 1);
 105                        break;
 106                case 1:
 107                        /* No stage 3 (merge) entry? That means it's been deleted */
 108                        if (!same) {
 109                                show_file("-", ce, ce->sha1, ce->ce_mode);
 110                                break;
 111                        }
 112                        /* We come here with ce pointing at stage 1
 113                         * (original tree) and ac[1] pointing at stage
 114                         * 3 (unmerged).  show-modified with
 115                         * report-mising set to false does not say the
 116                         * file is deleted but reports true if work
 117                         * tree does not have it, in which case we
 118                         * fall through to report the unmerged state.
 119                         * Otherwise, we show the differences between
 120                         * the original tree and the work tree.
 121                         */
 122                        if (!cached_only && !show_modified(ce, ac[1], 0))
 123                                break;
 124                        /* fallthru */
 125                case 3:
 126                        diff_unmerge(ce->name);
 127                        break;
 128
 129                default:
 130                        die("impossible cache entry stage");
 131                }
 132
 133                /*
 134                 * Ignore all the different stages for this file,
 135                 * we've handled the relevant cases now.
 136                 */
 137                do {
 138                        ac++;
 139                        entries--;
 140                } while (entries && ce_same_name(ce, ac[0]));
 141        }
 142        return 0;
 143}
 144
 145/*
 146 * This turns all merge entries into "stage 3". That guarantees that
 147 * when we read in the new tree (into "stage 1"), we won't lose sight
 148 * of the fact that we had unmerged entries.
 149 */
 150static void mark_merge_entries(void)
 151{
 152        int i;
 153        for (i = 0; i < active_nr; i++) {
 154                struct cache_entry *ce = active_cache[i];
 155                if (!ce_stage(ce))
 156                        continue;
 157                ce->ce_flags |= htons(CE_STAGEMASK);
 158        }
 159}
 160
 161static char *diff_cache_usage =
 162"git-diff-cache [-p] [-r] [-z] [-m] [--cached] [-R] [-B] [-M] [-C] [--find-copies-harder] [-O<orderfile>] [-S<string>] [--pickaxe-all] <tree-ish> [<path>...]";
 163
 164int main(int argc, const char **argv)
 165{
 166        const char *tree_name = NULL;
 167        unsigned char sha1[20];
 168        const char **pathspec = NULL;
 169        void *tree;
 170        unsigned long size;
 171        int ret;
 172        int allow_options = 1;
 173        int i;
 174
 175        read_cache();
 176        for (i = 1; i < argc; i++) {
 177                const char *arg = argv[i];
 178
 179                if (!allow_options || *arg != '-') {
 180                        if (tree_name) {
 181                                pathspec = argv + i;
 182                                break;
 183                        }
 184                        tree_name = arg;
 185                        continue;
 186                }
 187                        
 188                if (!strcmp(arg, "--")) {
 189                        allow_options = 0;
 190                        continue;
 191                }
 192                if (!strcmp(arg, "-r")) {
 193                        /* We accept the -r flag just to look like git-diff-tree */
 194                        continue;
 195                }
 196                if (!strcmp(arg, "-p")) {
 197                        diff_output_format = DIFF_FORMAT_PATCH;
 198                        continue;
 199                }
 200                if (!strncmp(arg, "-B", 2)) {
 201                        if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
 202                                usage(diff_cache_usage);
 203                        continue;
 204                }
 205                if (!strncmp(arg, "-M", 2)) {
 206                        detect_rename = DIFF_DETECT_RENAME;
 207                        if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 208                                usage(diff_cache_usage);
 209                        continue;
 210                }
 211                if (!strncmp(arg, "-C", 2)) {
 212                        detect_rename = DIFF_DETECT_COPY;
 213                        if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
 214                                usage(diff_cache_usage);
 215                        continue;
 216                }
 217                if (!strcmp(arg, "--find-copies-harder")) {
 218                        find_copies_harder = 1;
 219                        continue;
 220                }
 221                if (!strcmp(arg, "-z")) {
 222                        diff_output_format = DIFF_FORMAT_MACHINE;
 223                        continue;
 224                }
 225                if (!strcmp(arg, "-R")) {
 226                        diff_setup_opt |= DIFF_SETUP_REVERSE;
 227                        continue;
 228                }
 229                if (!strncmp(arg, "-S", 2)) {
 230                        pickaxe = arg + 2;
 231                        continue;
 232                }
 233                if (!strncmp(arg, "--diff-filter=", 14)) {
 234                        diff_filter = arg + 14;
 235                        continue;
 236                }
 237                if (!strncmp(arg, "-O", 2)) {
 238                        orderfile = arg + 2;
 239                        continue;
 240                }
 241                if (!strcmp(arg, "--pickaxe-all")) {
 242                        pickaxe_opts = DIFF_PICKAXE_ALL;
 243                        continue;
 244                }
 245                if (!strcmp(arg, "-m")) {
 246                        match_nonexisting = 1;
 247                        continue;
 248                }
 249                if (!strcmp(arg, "--cached")) {
 250                        cached_only = 1;
 251                        continue;
 252                }
 253                usage(diff_cache_usage);
 254        }
 255
 256        if (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
 257                usage(diff_cache_usage);
 258
 259        if (!tree_name || get_sha1(tree_name, sha1))
 260                usage(diff_cache_usage);
 261
 262        /* The rest is for paths restriction. */
 263        diff_setup(diff_setup_opt);
 264
 265        mark_merge_entries();
 266
 267        tree = read_object_with_reference(sha1, "tree", &size, NULL);
 268        if (!tree)
 269                die("bad tree object %s", tree_name);
 270        if (read_tree(tree, size, 1))
 271                die("unable to read tree object %s", tree_name);
 272
 273        ret = diff_cache(active_cache, active_nr);
 274
 275        diffcore_std(pathspec ? : NULL,
 276                     detect_rename, diff_score_opt,
 277                     pickaxe, pickaxe_opts,
 278                     diff_break_opt,
 279                     orderfile, diff_filter);
 280        diff_flush(diff_output_format);
 281        return ret;
 282}