Fix crash when reading the empty tree
[git.git] / diff-index.c
index 12a9418..8694012 100644 (file)
@@ -1,168 +1,7 @@
 #include "cache.h"
-#include "tree.h"
 #include "diff.h"
-
-static int cached_only = 0;
-static int match_nonexisting = 0;
-static struct diff_options diff_options;
-
-/* A file entry went away or appeared */
-static void show_file(const char *prefix,
-                     struct cache_entry *ce,
-                     unsigned char *sha1, unsigned int mode)
-{
-       diff_addremove(&diff_options, prefix[0], ntohl(mode),
-                      sha1, ce->name, NULL);
-}
-
-static int get_stat_data(struct cache_entry *ce,
-                        unsigned char ** sha1p, unsigned int *modep)
-{
-       unsigned char *sha1 = ce->sha1;
-       unsigned int mode = ce->ce_mode;
-
-       if (!cached_only) {
-               static unsigned char no_sha1[20];
-               int changed;
-               struct stat st;
-               if (lstat(ce->name, &st) < 0) {
-                       if (errno == ENOENT && match_nonexisting) {
-                               *sha1p = sha1;
-                               *modep = mode;
-                               return 0;
-                       }
-                       return -1;
-               }
-               changed = ce_match_stat(ce, &st, 0);
-               if (changed) {
-                       mode = create_ce_mode(st.st_mode);
-                       if (!trust_executable_bit &&
-                           S_ISREG(mode) && S_ISREG(ce->ce_mode) &&
-                           ((mode ^ ce->ce_mode) == 0111))
-                               mode = ce->ce_mode;
-                       sha1 = no_sha1;
-               }
-       }
-
-       *sha1p = sha1;
-       *modep = mode;
-       return 0;
-}
-
-static void show_new_file(struct cache_entry *new)
-{
-       unsigned char *sha1;
-       unsigned int mode;
-
-       /* New file in the index: it might actually be different in
-        * the working copy.
-        */
-       if (get_stat_data(new, &sha1, &mode) < 0)
-               return;
-
-       show_file("+", new, sha1, mode);
-}
-
-static int show_modified(struct cache_entry *old,
-                        struct cache_entry *new,
-                        int report_missing)
-{
-       unsigned int mode, oldmode;
-       unsigned char *sha1;
-
-       if (get_stat_data(new, &sha1, &mode) < 0) {
-               if (report_missing)
-                       show_file("-", old, old->sha1, old->ce_mode);
-               return -1;
-       }
-
-       oldmode = old->ce_mode;
-       if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
-           !diff_options.find_copies_harder)
-               return 0;
-
-       mode = ntohl(mode);
-       oldmode = ntohl(oldmode);
-
-       diff_change(&diff_options, oldmode, mode,
-                   old->sha1, sha1, old->name, NULL);
-       return 0;
-}
-
-static int diff_cache(struct cache_entry **ac, int entries, const char **pathspec)
-{
-       while (entries) {
-               struct cache_entry *ce = *ac;
-               int same = (entries > 1) && ce_same_name(ce, ac[1]);
-
-               if (!ce_path_match(ce, pathspec))
-                       goto skip_entry;
-
-               switch (ce_stage(ce)) {
-               case 0:
-                       /* No stage 1 entry? That means it's a new file */
-                       if (!same) {
-                               show_new_file(ce);
-                               break;
-                       }
-                       /* Show difference between old and new */
-                       show_modified(ac[1], ce, 1);
-                       break;
-               case 1:
-                       /* No stage 3 (merge) entry? That means it's been deleted */
-                       if (!same) {
-                               show_file("-", ce, ce->sha1, ce->ce_mode);
-                               break;
-                       }
-                       /* We come here with ce pointing at stage 1
-                        * (original tree) and ac[1] pointing at stage
-                        * 3 (unmerged).  show-modified with
-                        * report-missing set to false does not say the
-                        * file is deleted but reports true if work
-                        * tree does not have it, in which case we
-                        * fall through to report the unmerged state.
-                        * Otherwise, we show the differences between
-                        * the original tree and the work tree.
-                        */
-                       if (!cached_only && !show_modified(ce, ac[1], 0))
-                               break;
-                       /* fallthru */
-               case 3:
-                       diff_unmerge(&diff_options, ce->name);
-                       break;
-
-               default:
-                       die("impossible cache entry stage");
-               }
-
-skip_entry:
-               /*
-                * Ignore all the different stages for this file,
-                * we've handled the relevant cases now.
-                */
-               do {
-                       ac++;
-                       entries--;
-               } while (entries && ce_same_name(ce, ac[0]));
-       }
-       return 0;
-}
-
-/*
- * This turns all merge entries into "stage 3". That guarantees that
- * when we read in the new tree (into "stage 1"), we won't lose sight
- * of the fact that we had unmerged entries.
- */
-static void mark_merge_entries(void)
-{
-       int i;
-       for (i = 0; i < active_nr; i++) {
-               struct cache_entry *ce = active_cache[i];
-               if (!ce_stage(ce))
-                       continue;
-               ce->ce_flags |= htons(CE_STAGEMASK);
-       }
-}
+#include "commit.h"
+#include "revision.h"
 
 static const char diff_cache_usage[] =
 "git-diff-index [-m] [--cached] "
@@ -171,85 +10,30 @@ COMMON_DIFF_OPTIONS_HELP;
 
 int main(int argc, const char **argv)
 {
-       const char *tree_name = NULL;
-       unsigned char sha1[20];
-       const char *prefix = setup_git_directory();
-       const char **pathspec = NULL;
-       struct tree *tree;
-       int ret;
-       int allow_options = 1;
+       struct rev_info rev;
+       int match_missing = 0;
+       int cached = 0;
        int i;
 
        git_config(git_diff_config);
-       diff_setup(&diff_options);
+       init_revisions(&rev);
+       rev.abbrev = 0;
+
+       argc = setup_revisions(argc, argv, &rev, NULL);
        for (i = 1; i < argc; i++) {
                const char *arg = argv[i];
-               int diff_opt_cnt;
-
-               if (!allow_options || *arg != '-') {
-                       if (tree_name)
-                               break;
-                       tree_name = arg;
-                       continue;
-               }
                        
-               if (!strcmp(arg, "--")) {
-                       allow_options = 0;
-                       continue;
-               }
-               if (!strcmp(arg, "-r")) {
-                       /* We accept the -r flag just to look like git-diff-tree */
-                       continue;
-               }
-               if (!strcmp(arg, "--cc"))
-                       /*
-                        * I _think_ "diff-index --cached HEAD" with an
-                        * unmerged index could show something else
-                        * later, but pretend --cc is the same as -p for
-                        * now.  "git diff" uses --cc by default.
-                        */
-                       argv[i] = arg = "-p";
-               diff_opt_cnt = diff_opt_parse(&diff_options, argv + i,
-                                             argc - i);
-               if (diff_opt_cnt < 0)
+               if (!strcmp(arg, "--cached"))
+                       cached = 1;
+               else
                        usage(diff_cache_usage);
-               else if (diff_opt_cnt) {
-                       i += diff_opt_cnt - 1;
-                       continue;
-               }
-
-               if (!strcmp(arg, "-m")) {
-                       match_nonexisting = 1;
-                       continue;
-               }
-               if (!strcmp(arg, "--cached")) {
-                       cached_only = 1;
-                       continue;
-               }
-               usage(diff_cache_usage);
        }
-
-       pathspec = get_pathspec(prefix, argv + i);
-
-       if (diff_setup_done(&diff_options) < 0)
-               usage(diff_cache_usage);
-
-       if (!tree_name || get_sha1(tree_name, sha1))
+       /*
+        * Make sure there is one revision (i.e. pending object),
+        * and there is no revision filtering parameters.
+        */
+       if (!rev.pending_objects || rev.pending_objects->next ||
+           rev.max_count != -1 || rev.min_age != -1 || rev.max_age != -1)
                usage(diff_cache_usage);
-
-       read_cache();
-
-       mark_merge_entries();
-
-       tree = parse_tree_indirect(sha1);
-       if (!tree)
-               die("bad tree object %s", tree_name);
-       if (read_tree(tree, 1, pathspec))
-               die("unable to read tree object %s", tree_name);
-
-       ret = diff_cache(active_cache, active_nr, pathspec);
-
-       diffcore_std(&diff_options);
-       diff_flush(&diff_options);
-       return ret;
+       return run_diff_index(&rev, cached);
 }