Big tool rename.
[git.git] / diff-index.c
diff --git a/diff-index.c b/diff-index.c
new file mode 100644 (file)
index 0000000..bc41d54
--- /dev/null
@@ -0,0 +1,296 @@
+#include "cache.h"
+#include "diff.h"
+
+static int cached_only = 0;
+static int diff_output_format = DIFF_FORMAT_RAW;
+static int diff_line_termination = '\n';
+static int match_nonexisting = 0;
+static int detect_rename = 0;
+static int find_copies_harder = 0;
+static int diff_setup_opt = 0;
+static int diff_score_opt = 0;
+static const char *pickaxe = NULL;
+static int pickaxe_opts = 0;
+static int diff_break_opt = -1;
+static const char *orderfile = NULL;
+static const char *diff_filter = NULL;
+
+/* 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(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);
+               if (changed) {
+                       mode = create_ce_mode(st.st_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) &&
+           !find_copies_harder)
+               return 0;
+
+       mode = ntohl(mode);
+       oldmode = ntohl(oldmode);
+
+       diff_change(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-mising 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(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);
+       }
+}
+
+static const char diff_cache_usage[] =
+"git-diff-index [-m] [--cached] "
+"[<common diff options>] <tree-ish> [<path>...]"
+COMMON_DIFF_OPTIONS_HELP;
+
+int main(int argc, char **argv)
+{
+       const char *tree_name = NULL;
+       unsigned char sha1[20];
+       const char *prefix = setup_git_directory();
+       const char **pathspec = NULL;
+       void *tree;
+       unsigned long size;
+       int ret;
+       int allow_options = 1;
+       int i;
+
+       for (i = 1; i < argc; i++) {
+               const char *arg = argv[i];
+
+               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;
+               }
+               /* We accept the -u flag as a synonym for "-p" */
+               if (!strcmp(arg, "-p") || !strcmp(arg, "-u")) {
+                       diff_output_format = DIFF_FORMAT_PATCH;
+                       continue;
+               }
+               if (!strncmp(arg, "-B", 2)) {
+                       if ((diff_break_opt = diff_scoreopt_parse(arg)) == -1)
+                               usage(diff_cache_usage);
+                       continue;
+               }
+               if (!strncmp(arg, "-M", 2)) {
+                       detect_rename = DIFF_DETECT_RENAME;
+                       if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
+                               usage(diff_cache_usage);
+                       continue;
+               }
+               if (!strncmp(arg, "-C", 2)) {
+                       detect_rename = DIFF_DETECT_COPY;
+                       if ((diff_score_opt = diff_scoreopt_parse(arg)) == -1)
+                               usage(diff_cache_usage);
+                       continue;
+               }
+               if (!strcmp(arg, "--find-copies-harder")) {
+                       find_copies_harder = 1;
+                       continue;
+               }
+               if (!strcmp(arg, "-z")) {
+                       diff_line_termination = 0;
+                       continue;
+               }
+               if (!strcmp(arg, "--name-only")) {
+                       diff_output_format = DIFF_FORMAT_NAME;
+                       continue;
+               }
+               if (!strcmp(arg, "-R")) {
+                       diff_setup_opt |= DIFF_SETUP_REVERSE;
+                       continue;
+               }
+               if (!strncmp(arg, "-S", 2)) {
+                       pickaxe = arg + 2;
+                       continue;
+               }
+               if (!strncmp(arg, "--diff-filter=", 14)) {
+                       diff_filter = arg + 14;
+                       continue;
+               }
+               if (!strncmp(arg, "-O", 2)) {
+                       orderfile = arg + 2;
+                       continue;
+               }
+               if (!strcmp(arg, "--pickaxe-all")) {
+                       pickaxe_opts = DIFF_PICKAXE_ALL;
+                       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 (find_copies_harder && detect_rename != DIFF_DETECT_COPY)
+               usage(diff_cache_usage);
+
+       if (!tree_name || get_sha1(tree_name, sha1))
+               usage(diff_cache_usage);
+
+       read_cache();
+
+       /* The rest is for paths restriction. */
+       diff_setup(diff_setup_opt);
+
+       mark_merge_entries();
+
+       tree = read_object_with_reference(sha1, "tree", &size, NULL);
+       if (!tree)
+               die("bad tree object %s", tree_name);
+       if (read_tree(tree, size, 1, pathspec))
+               die("unable to read tree object %s", tree_name);
+
+       ret = diff_cache(active_cache, active_nr, pathspec);
+
+       diffcore_std(pathspec,
+                    detect_rename, diff_score_opt,
+                    pickaxe, pickaxe_opts,
+                    diff_break_opt,
+                    orderfile, diff_filter);
+       diff_flush(diff_output_format, diff_line_termination);
+       return ret;
+}