diff-cache.con commit t/t4003-diff-rename-1: use modern options to "diff" (da196b6)
   1#include "cache.h"
   2#include "diff.h"
   3
   4static int cached_only = 0;
   5static int generate_patch = 0;
   6static int match_nonexisting = 0;
   7static int line_termination = '\n';
   8static int detect_rename = 0;
   9static int reverse_diff = 0;
  10static int diff_score_opt = 0;
  11static char *pickaxe = 0;
  12
  13/* A file entry went away or appeared */
  14static void show_file(const char *prefix, struct cache_entry *ce, unsigned char *sha1, unsigned int mode)
  15{
  16        diff_addremove(prefix[0], ntohl(mode), sha1, ce->name, NULL);
  17}
  18
  19static int get_stat_data(struct cache_entry *ce, unsigned char **sha1p, unsigned int *modep)
  20{
  21        unsigned char *sha1 = ce->sha1;
  22        unsigned int mode = ce->ce_mode;
  23
  24        if (!cached_only) {
  25                static unsigned char no_sha1[20];
  26                int changed;
  27                struct stat st;
  28                if (lstat(ce->name, &st) < 0) {
  29                        if (errno == ENOENT && match_nonexisting) {
  30                                *sha1p = sha1;
  31                                *modep = mode;
  32                                return 0;
  33                        }
  34                        return -1;
  35                }
  36                changed = ce_match_stat(ce, &st);
  37                if (changed) {
  38                        mode = create_ce_mode(st.st_mode);
  39                        sha1 = no_sha1;
  40                }
  41        }
  42
  43        *sha1p = sha1;
  44        *modep = mode;
  45        return 0;
  46}
  47
  48static void show_new_file(struct cache_entry *new)
  49{
  50        unsigned char *sha1;
  51        unsigned int mode;
  52
  53        /* New file in the index: it might actually be different in the working copy */
  54        if (get_stat_data(new, &sha1, &mode) < 0)
  55                return;
  56
  57        show_file("+", new, sha1, mode);
  58}
  59
  60static int show_modified(struct cache_entry *old,
  61                         struct cache_entry *new,
  62                         int report_missing)
  63{
  64        unsigned int mode, oldmode;
  65        unsigned char *sha1;
  66
  67        if (get_stat_data(new, &sha1, &mode) < 0) {
  68                if (report_missing)
  69                        show_file("-", old, old->sha1, old->ce_mode);
  70                return -1;
  71        }
  72
  73        oldmode = old->ce_mode;
  74        if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
  75            detect_rename < 2)
  76                return 0;
  77
  78        mode = ntohl(mode);
  79        oldmode = ntohl(oldmode);
  80
  81        diff_change(oldmode, mode,
  82                    old->sha1, sha1, old->name, NULL);
  83        return 0;
  84}
  85
  86static int diff_cache(struct cache_entry **ac, int entries)
  87{
  88        while (entries) {
  89                struct cache_entry *ce = *ac;
  90                int same = (entries > 1) && ce_same_name(ce, ac[1]);
  91
  92                switch (ce_stage(ce)) {
  93                case 0:
  94                        /* No stage 1 entry? That means it's a new file */
  95                        if (!same) {
  96                                show_new_file(ce);
  97                                break;
  98                        }
  99                        /* Show difference between old and new */
 100                        show_modified(ac[1], ce, 1);
 101                        break;
 102                case 1:
 103                        /* No stage 3 (merge) entry? That means it's been deleted */
 104                        if (!same) {
 105                                show_file("-", ce, ce->sha1, ce->ce_mode);
 106                                break;
 107                        }
 108                        /* We come here with ce pointing at stage 1
 109                         * (original tree) and ac[1] pointing at stage
 110                         * 3 (unmerged).  show-modified with
 111                         * report-mising set to false does not say the
 112                         * file is deleted but reports true if work
 113                         * tree does not have it, in which case we
 114                         * fall through to report the unmerged state.
 115                         * Otherwise, we show the differences between
 116                         * the original tree and the work tree.
 117                         */
 118                        if (!cached_only && !show_modified(ce, ac[1], 0))
 119                                break;
 120                        /* fallthru */
 121                case 3:
 122                        diff_unmerge(ce->name);
 123                        break;
 124
 125                default:
 126                        die("impossible cache entry stage");
 127                }
 128
 129                /*
 130                 * Ignore all the different stages for this file,
 131                 * we've handled the relevant cases now.
 132                 */
 133                do {
 134                        ac++;
 135                        entries--;
 136                } while (entries && ce_same_name(ce, ac[0]));
 137        }
 138        return 0;
 139}
 140
 141/*
 142 * This turns all merge entries into "stage 3". That guarantees that
 143 * when we read in the new tree (into "stage 1"), we won't lose sight
 144 * of the fact that we had unmerged entries.
 145 */
 146static void mark_merge_entries(void)
 147{
 148        int i;
 149        for (i = 0; i < active_nr; i++) {
 150                struct cache_entry *ce = active_cache[i];
 151                if (!ce_stage(ce))
 152                        continue;
 153                ce->ce_flags |= htons(CE_STAGEMASK);
 154        }
 155}
 156
 157static char *diff_cache_usage =
 158"git-diff-cache [-p] [-r] [-z] [-m] [-M] [-C] [-R] [-S<string>] [--cached] <tree-ish>";
 159
 160int main(int argc, char **argv)
 161{
 162        unsigned char tree_sha1[20];
 163        void *tree;
 164        unsigned long size;
 165        int ret;
 166
 167        read_cache();
 168        while (argc > 2) {
 169                char *arg = argv[1];
 170                argv++;
 171                argc--;
 172                if (!strcmp(arg, "-r")) {
 173                        /* We accept the -r flag just to look like git-diff-tree */
 174                        continue;
 175                }
 176                if (!strcmp(arg, "-p")) {
 177                        generate_patch = 1;
 178                        continue;
 179                }
 180                if (!strncmp(arg, "-M", 2)) {
 181                        generate_patch = detect_rename = 1;
 182                        diff_score_opt = diff_scoreopt_parse(arg);
 183                        continue;
 184                }
 185                if (!strncmp(arg, "-C", 2)) {
 186                        generate_patch = 1;
 187                        detect_rename = 2;
 188                        diff_score_opt = diff_scoreopt_parse(arg);
 189                        continue;
 190                }
 191                if (!strcmp(arg, "-z")) {
 192                        line_termination = '\0';
 193                        continue;
 194                }
 195                if (!strcmp(arg, "-R")) {
 196                        reverse_diff = 1;
 197                        continue;
 198                }
 199                if (!strcmp(arg, "-S")) {
 200                        pickaxe = arg + 2;
 201                        continue;
 202                }
 203                if (!strcmp(arg, "-m")) {
 204                        match_nonexisting = 1;
 205                        continue;
 206                }
 207                if (!strcmp(arg, "--cached")) {
 208                        cached_only = 1;
 209                        continue;
 210                }
 211                usage(diff_cache_usage);
 212        }
 213
 214        if (argc != 2 || get_sha1(argv[1], tree_sha1))
 215                usage(diff_cache_usage);
 216
 217        diff_setup(detect_rename, diff_score_opt, pickaxe,
 218                   reverse_diff, (generate_patch ? -1 : line_termination),
 219                   NULL, 0);
 220
 221        mark_merge_entries();
 222
 223        tree = read_object_with_reference(tree_sha1, "tree", &size, NULL);
 224        if (!tree)
 225                die("bad tree object %s", argv[1]);
 226        if (read_tree(tree, size, 1))
 227                die("unable to read tree object %s", argv[1]);
 228
 229        ret = diff_cache(active_cache, active_nr);
 230        diff_flush();
 231        return ret;
 232}