Andrew's git - gitweb.git/blob

   1#include "cache.h"
   2#include "tree.h"
   3#include "diff.h"
   4
   5static int cached_only = 0;
   6static int match_nonexisting = 0;
   7static struct diff_options diff_options;
   8
   9/* A file entry went away or appeared */
  10static void show_file(const char *prefix,
  11                      struct cache_entry *ce,
  12                      unsigned char *sha1, unsigned int mode)
  13{
  14        diff_addremove(&diff_options, prefix[0], ntohl(mode),
  15                       sha1, ce->name, NULL);
  16}
  17
  18static int get_stat_data(struct cache_entry *ce,
  19                         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, 0);
  37                if (changed) {
  38                        mode = create_ce_mode(st.st_mode);
  39                        if (!trust_executable_bit && S_ISREG(st.st_mode))
  40                                mode = ce->ce_mode;
  41                        sha1 = no_sha1;
  42                }
  43        }
  44
  45        *sha1p = sha1;
  46        *modep = mode;
  47        return 0;
  48}
  49
  50static void show_new_file(struct cache_entry *new)
  51{
  52        unsigned char *sha1;
  53        unsigned int mode;
  54
  55        /* New file in the index: it might actually be different in
  56         * the working copy.
  57         */
  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            !diff_options.find_copies_harder)
  80                return 0;
  81
  82        mode = ntohl(mode);
  83        oldmode = ntohl(oldmode);
  84
  85        diff_change(&diff_options, oldmode, mode,
  86                    old->sha1, sha1, old->name, NULL);
  87        return 0;
  88}
  89
  90static int diff_cache(struct cache_entry **ac, int entries, const char **pathspec)
  91{
  92        while (entries) {
  93                struct cache_entry *ce = *ac;
  94                int same = (entries > 1) && ce_same_name(ce, ac[1]);
  95
  96                if (!ce_path_match(ce, pathspec))
  97                        goto skip_entry;
  98
  99                switch (ce_stage(ce)) {
 100                case 0:
 101                        /* No stage 1 entry? That means it's a new file */
 102                        if (!same) {
 103                                show_new_file(ce);
 104                                break;
 105                        }
 106                        /* Show difference between old and new */
 107                        show_modified(ac[1], ce, 1);
 108                        break;
 109                case 1:
 110                        /* No stage 3 (merge) entry? That means it's been deleted */
 111                        if (!same) {
 112                                show_file("-", ce, ce->sha1, ce->ce_mode);
 113                                break;
 114                        }
 115                        /* We come here with ce pointing at stage 1
 116                         * (original tree) and ac[1] pointing at stage
 117                         * 3 (unmerged).  show-modified with
 118                         * report-missing set to false does not say the
 119                         * file is deleted but reports true if work
 120                         * tree does not have it, in which case we
 121                         * fall through to report the unmerged state.
 122                         * Otherwise, we show the differences between
 123                         * the original tree and the work tree.
 124                         */
 125                        if (!cached_only && !show_modified(ce, ac[1], 0))
 126                                break;
 127                        /* fallthru */
 128                case 3:
 129                        diff_unmerge(&diff_options, ce->name);
 130                        break;
 131
 132                default:
 133                        die("impossible cache entry stage");
 134                }
 135
 136skip_entry:
 137                /*
 138                 * Ignore all the different stages for this file,
 139                 * we've handled the relevant cases now.
 140                 */
 141                do {
 142                        ac++;
 143                        entries--;
 144                } while (entries && ce_same_name(ce, ac[0]));
 145        }
 146        return 0;
 147}
 148
 149/*
 150 * This turns all merge entries into "stage 3". That guarantees that
 151 * when we read in the new tree (into "stage 1"), we won't lose sight
 152 * of the fact that we had unmerged entries.
 153 */
 154static void mark_merge_entries(void)
 155{
 156        int i;
 157        for (i = 0; i < active_nr; i++) {
 158                struct cache_entry *ce = active_cache[i];
 159                if (!ce_stage(ce))
 160                        continue;
 161                ce->ce_flags |= htons(CE_STAGEMASK);
 162        }
 163}
 164
 165static const char diff_cache_usage[] =
 166"git-diff-index [-m] [--cached] "
 167"[<common diff options>] <tree-ish> [<path>...]"
 168COMMON_DIFF_OPTIONS_HELP;
 169
 170int main(int argc, const char **argv)
 171{
 172        const char *tree_name = NULL;
 173        unsigned char sha1[20];
 174        const char *prefix = setup_git_directory();
 175        const char **pathspec = NULL;
 176        struct tree *tree;
 177        int ret;
 178        int allow_options = 1;
 179        int i;
 180
 181        git_config(git_diff_config);
 182        diff_setup(&diff_options);
 183        for (i = 1; i < argc; i++) {
 184                const char *arg = argv[i];
 185                int diff_opt_cnt;
 186
 187                if (!allow_options || *arg != '-') {
 188                        if (tree_name)
 189                                break;
 190                        tree_name = arg;
 191                        continue;
 192                }
 193                        
 194                if (!strcmp(arg, "--")) {
 195                        allow_options = 0;
 196                        continue;
 197                }
 198                if (!strcmp(arg, "-r")) {
 199                        /* We accept the -r flag just to look like git-diff-tree */
 200                        continue;
 201                }
 202                if (!strcmp(arg, "--cc"))
 203                        /*
 204                         * I _think_ "diff-index --cached HEAD" with an
 205                         * unmerged index could show something else
 206                         * later, but pretend --cc is the same as -p for
 207                         * now.  "git diff" uses --cc by default.
 208                         */
 209                        argv[i] = arg = "-p";
 210                diff_opt_cnt = diff_opt_parse(&diff_options, argv + i,
 211                                              argc - i);
 212                if (diff_opt_cnt < 0)
 213                        usage(diff_cache_usage);
 214                else if (diff_opt_cnt) {
 215                        i += diff_opt_cnt - 1;
 216                        continue;
 217                }
 218
 219                if (!strcmp(arg, "-m")) {
 220                        match_nonexisting = 1;
 221                        continue;
 222                }
 223                if (!strcmp(arg, "--cached")) {
 224                        cached_only = 1;
 225                        continue;
 226                }
 227                usage(diff_cache_usage);
 228        }
 229
 230        pathspec = get_pathspec(prefix, argv + i);
 231
 232        if (diff_setup_done(&diff_options) < 0)
 233                usage(diff_cache_usage);
 234
 235        if (!tree_name || get_sha1(tree_name, sha1))
 236                usage(diff_cache_usage);
 237
 238        read_cache();
 239
 240        mark_merge_entries();
 241
 242        tree = parse_tree_indirect(sha1);
 243        if (!tree)
 244                die("bad tree object %s", tree_name);
 245        if (read_tree(tree, 1, pathspec))
 246                die("unable to read tree object %s", tree_name);
 247
 248        ret = diff_cache(active_cache, active_nr, pathspec);
 249
 250        diffcore_std(&diff_options);
 251        diff_flush(&diff_options);
 252        return ret;
 253}