Reduce the number of connects when fetching
[gitweb.git] / diff-lib.c
index 2183b41b03d08092ba6d98a642757640b86710d6..d85d8f34ba055ad7e02bf5d61ae4a675ce0be1d3 100644 (file)
 #include "diff.h"
 #include "diffcore.h"
 #include "revision.h"
+#include "cache-tree.h"
+#include "path-list.h"
 
 /*
  * diff-files
  */
 
-int run_diff_files(struct rev_info *revs, int silent_on_removed)
+static int read_directory(const char *path, struct path_list *list)
+{
+       DIR *dir;
+       struct dirent *e;
+
+       if (!(dir = opendir(path)))
+               return error("Could not open directory %s", path);
+
+       while ((e = readdir(dir)))
+               if (strcmp(".", e->d_name) && strcmp("..", e->d_name))
+                       path_list_insert(e->d_name, list);
+
+       closedir(dir);
+       return 0;
+}
+
+static int get_mode(const char *path, int *mode)
+{
+       struct stat st;
+
+       if (!path || !strcmp(path, "/dev/null"))
+               *mode = 0;
+       else if (!strcmp(path, "-"))
+               *mode = ntohl(create_ce_mode(0666));
+       else if (stat(path, &st))
+               return error("Could not access '%s'", path);
+       else
+               *mode = st.st_mode;
+       return 0;
+}
+
+static int queue_diff(struct diff_options *o,
+               const char *name1, const char *name2)
+{
+       int mode1 = 0, mode2 = 0;
+
+       if (get_mode(name1, &mode1) || get_mode(name2, &mode2))
+               return -1;
+
+       if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2))
+               return error("file/directory conflict: %s, %s", name1, name2);
+
+       if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
+               char buffer1[PATH_MAX], buffer2[PATH_MAX];
+               struct path_list p1 = {NULL, 0, 0, 1}, p2 = {NULL, 0, 0, 1};
+               int len1 = 0, len2 = 0, i1, i2, ret = 0;
+
+               if (name1 && read_directory(name1, &p1))
+                       return -1;
+               if (name2 && read_directory(name2, &p2)) {
+                       path_list_clear(&p1, 0);
+                       return -1;
+               }
+
+               if (name1) {
+                       len1 = strlen(name1);
+                       if (len1 > 0 && name1[len1 - 1] == '/')
+                               len1--;
+                       memcpy(buffer1, name1, len1);
+                       buffer1[len1++] = '/';
+               }
+
+               if (name2) {
+                       len2 = strlen(name2);
+                       if (len2 > 0 && name2[len2 - 1] == '/')
+                               len2--;
+                       memcpy(buffer2, name2, len2);
+                       buffer2[len2++] = '/';
+               }
+
+               for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
+                       const char *n1, *n2;
+                       int comp;
+
+                       if (i1 == p1.nr)
+                               comp = 1;
+                       else if (i2 == p2.nr)
+                               comp = -1;
+                       else
+                               comp = strcmp(p1.items[i1].path,
+                                       p2.items[i2].path);
+
+                       if (comp > 0)
+                               n1 = NULL;
+                       else {
+                               n1 = buffer1;
+                               strncpy(buffer1 + len1, p1.items[i1++].path,
+                                               PATH_MAX - len1);
+                       }
+
+                       if (comp < 0)
+                               n2 = NULL;
+                       else {
+                               n2 = buffer2;
+                               strncpy(buffer2 + len2, p2.items[i2++].path,
+                                               PATH_MAX - len2);
+                       }
+
+                       ret = queue_diff(o, n1, n2);
+               }
+               path_list_clear(&p1, 0);
+               path_list_clear(&p2, 0);
+
+               return ret;
+       } else {
+               struct diff_filespec *d1, *d2;
+
+               if (DIFF_OPT_TST(o, REVERSE_DIFF)) {
+                       unsigned tmp;
+                       const char *tmp_c;
+                       tmp = mode1; mode1 = mode2; mode2 = tmp;
+                       tmp_c = name1; name1 = name2; name2 = tmp_c;
+               }
+
+               if (!name1)
+                       name1 = "/dev/null";
+               if (!name2)
+                       name2 = "/dev/null";
+               d1 = alloc_filespec(name1);
+               d2 = alloc_filespec(name2);
+               fill_filespec(d1, null_sha1, mode1);
+               fill_filespec(d2, null_sha1, mode2);
+
+               diff_queue(&diff_queued_diff, d1, d2);
+               return 0;
+       }
+}
+
+/*
+ * Does the path name a blob in the working tree, or a directory
+ * in the working tree?
+ */
+static int is_in_index(const char *path)
+{
+       int len, pos;
+       struct cache_entry *ce;
+
+       len = strlen(path);
+       while (path[len-1] == '/')
+               len--;
+       if (!len)
+               return 1; /* "." */
+       pos = cache_name_pos(path, len);
+       if (0 <= pos)
+               return 1;
+       pos = -1 - pos;
+       while (pos < active_nr) {
+               ce = active_cache[pos++];
+               if (ce_namelen(ce) <= len ||
+                   strncmp(ce->name, path, len) ||
+                   (ce->name[len] > '/'))
+                       break; /* path cannot be a prefix */
+               if (ce->name[len] == '/')
+                       return 1;
+       }
+       return 0;
+}
+
+static int handle_diff_files_args(struct rev_info *revs,
+                                 int argc, const char **argv,
+                                 unsigned int *options)
+{
+       *options = 0;
+
+       /* revs->max_count == -2 means --no-index */
+       while (1 < argc && argv[1][0] == '-') {
+               if (!strcmp(argv[1], "--base"))
+                       revs->max_count = 1;
+               else if (!strcmp(argv[1], "--ours"))
+                       revs->max_count = 2;
+               else if (!strcmp(argv[1], "--theirs"))
+                       revs->max_count = 3;
+               else if (!strcmp(argv[1], "-n") ||
+                               !strcmp(argv[1], "--no-index")) {
+                       revs->max_count = -2;
+                       DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
+                       DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
+               }
+               else if (!strcmp(argv[1], "-q"))
+                       *options |= DIFF_SILENT_ON_REMOVED;
+               else
+                       return error("invalid option: %s", argv[1]);
+               argv++; argc--;
+       }
+
+       if (revs->max_count == -1 && revs->diffopt.nr_paths == 2) {
+               /*
+                * If two files are specified, and at least one is untracked,
+                * default to no-index.
+                */
+               read_cache();
+               if (!is_in_index(revs->diffopt.paths[0]) ||
+                                       !is_in_index(revs->diffopt.paths[1])) {
+                       revs->max_count = -2;
+                       DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
+               }
+       }
+
+       /*
+        * Make sure there are NO revision (i.e. pending object) parameter,
+        * rev.max_count is reasonable (0 <= n <= 3),
+        * there is no other revision filtering parameters.
+        */
+       if (revs->pending.nr || revs->max_count > 3 ||
+           revs->min_age != -1 || revs->max_age != -1)
+               return error("no revision allowed with diff-files");
+
+       if (revs->max_count == -1 &&
+           (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
+               revs->combine_merges = revs->dense_combined_merges = 1;
+
+       return 0;
+}
+
+static int is_outside_repo(const char *path, int nongit, const char *prefix)
+{
+       int i;
+       if (nongit || !strcmp(path, "-") || is_absolute_path(path))
+               return 1;
+       if (prefixcmp(path, "../"))
+               return 0;
+       if (!prefix)
+               return 1;
+       for (i = strlen(prefix); !prefixcmp(path, "../"); ) {
+               while (i > 0 && prefix[i - 1] != '/')
+                       i--;
+               if (--i < 0)
+                       return 1;
+               path += 3;
+       }
+       return 0;
+}
+
+int setup_diff_no_index(struct rev_info *revs,
+               int argc, const char ** argv, int nongit, const char *prefix)
+{
+       int i;
+       for (i = 1; i < argc; i++)
+               if (argv[i][0] != '-' || argv[i][1] == '\0')
+                       break;
+               else if (!strcmp(argv[i], "--")) {
+                       i++;
+                       break;
+               } else if (i < argc - 3 && !strcmp(argv[i], "--no-index")) {
+                       i = argc - 3;
+                       DIFF_OPT_SET(&revs->diffopt, EXIT_WITH_STATUS);
+                       break;
+               }
+       if (argc != i + 2 || (!is_outside_repo(argv[i + 1], nongit, prefix) &&
+                               !is_outside_repo(argv[i], nongit, prefix)))
+               return -1;
+
+       diff_setup(&revs->diffopt);
+       for (i = 1; i < argc - 2; )
+               if (!strcmp(argv[i], "--no-index"))
+                       i++;
+               else {
+                       int j = diff_opt_parse(&revs->diffopt,
+                                       argv + i, argc - i);
+                       if (!j)
+                               die("invalid diff option/value: %s", argv[i]);
+                       i += j;
+               }
+
+       if (prefix) {
+               int len = strlen(prefix);
+
+               revs->diffopt.paths = xcalloc(2, sizeof(char*));
+               for (i = 0; i < 2; i++) {
+                       const char *p = argv[argc - 2 + i];
+                       /*
+                        * stdin should be spelled as '-'; if you have
+                        * path that is '-', spell it as ./-.
+                        */
+                       p = (strcmp(p, "-")
+                            ? xstrdup(prefix_filename(prefix, len, p))
+                            : p);
+                       revs->diffopt.paths[i] = p;
+               }
+       }
+       else
+               revs->diffopt.paths = argv + argc - 2;
+       revs->diffopt.nr_paths = 2;
+       DIFF_OPT_SET(&revs->diffopt, NO_INDEX);
+       revs->max_count = -2;
+       if (diff_setup_done(&revs->diffopt) < 0)
+               die("diff_setup_done failed");
+       return 0;
+}
+
+int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
+{
+       unsigned int options;
+
+       if (handle_diff_files_args(revs, argc, argv, &options))
+               return -1;
+
+       if (DIFF_OPT_TST(&revs->diffopt, NO_INDEX)) {
+               if (revs->diffopt.nr_paths != 2)
+                       return error("need two files/directories with --no-index");
+               if (queue_diff(&revs->diffopt, revs->diffopt.paths[0],
+                               revs->diffopt.paths[1]))
+                       return -1;
+               diffcore_std(&revs->diffopt);
+               diff_flush(&revs->diffopt);
+               /*
+                * The return code for --no-index imitates diff(1):
+                * 0 = no changes, 1 = changes, else error
+                */
+               return revs->diffopt.found_changes;
+       }
+
+       if (read_cache() < 0) {
+               perror("read_cache");
+               return -1;
+       }
+       return run_diff_files(revs, options);
+}
+
+int run_diff_files(struct rev_info *revs, unsigned int option)
 {
        int entries, i;
        int diff_unmerged_stage = revs->max_count;
+       int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
+       unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
+                             ? CE_MATCH_RACY_IS_DIRTY : 0);
 
        if (diff_unmerged_stage < 0)
                diff_unmerged_stage = 2;
-       entries = read_cache();
-       if (entries < 0) {
-               perror("read_cache");
-               return -1;
-       }
+       entries = active_nr;
        for (i = 0; i < entries; i++) {
                struct stat st;
                unsigned int oldmode, newmode;
                struct cache_entry *ce = active_cache[i];
                int changed;
 
+               if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
+                       DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
+                       break;
+
                if (!ce_path_match(ce, revs->prune_data))
                        continue;
 
                if (ce_stage(ce)) {
-                       struct {
-                               struct combine_diff_path p;
-                               struct combine_diff_parent filler[5];
-                       } combine;
+                       struct combine_diff_path *dpath;
                        int num_compare_stages = 0;
+                       size_t path_len;
+
+                       path_len = ce_namelen(ce);
+
+                       dpath = xmalloc(combine_diff_path_size(5, path_len));
+                       dpath->path = (char *) &(dpath->parent[5]);
 
-                       combine.p.next = NULL;
-                       combine.p.len = ce_namelen(ce);
-                       combine.p.path = xmalloc(combine.p.len + 1);
-                       memcpy(combine.p.path, ce->name, combine.p.len);
-                       combine.p.path[combine.p.len] = 0;
-                       combine.p.mode = 0;
-                       memset(combine.p.sha1, 0, 20);
-                       memset(&combine.p.parent[0], 0,
-                              sizeof(combine.filler));
+                       dpath->next = NULL;
+                       dpath->len = path_len;
+                       memcpy(dpath->path, ce->name, path_len);
+                       dpath->path[path_len] = '\0';
+                       hashclr(dpath->sha1);
+                       memset(&(dpath->parent[0]), 0,
+                              sizeof(struct combine_diff_parent)*5);
+
+                       if (lstat(ce->name, &st) < 0) {
+                               if (errno != ENOENT && errno != ENOTDIR) {
+                                       perror(ce->name);
+                                       continue;
+                               }
+                               if (silent_on_removed)
+                                       continue;
+                       }
+                       else
+                               dpath->mode = ntohl(ce_mode_from_stat(ce, st.st_mode));
 
                        while (i < entries) {
                                struct cache_entry *nce = active_cache[i];
@@ -64,11 +400,9 @@ int run_diff_files(struct rev_info *revs, int silent_on_removed)
                                if (2 <= stage) {
                                        int mode = ntohl(nce->ce_mode);
                                        num_compare_stages++;
-                                       memcpy(combine.p.parent[stage-2].sha1,
-                                              nce->sha1, 20);
-                                       combine.p.parent[stage-2].mode =
-                                               canon_mode(mode);
-                                       combine.p.parent[stage-2].status =
+                                       hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
+                                       dpath->parent[stage-2].mode = ntohl(ce_mode_from_stat(nce, mode));
+                                       dpath->parent[stage-2].status =
                                                DIFF_STATUS_MODIFIED;
                                }
 
@@ -83,19 +417,20 @@ int run_diff_files(struct rev_info *revs, int silent_on_removed)
                        i--;
 
                        if (revs->combine_merges && num_compare_stages == 2) {
-                               show_combined_diff(&combine.p, 2,
+                               show_combined_diff(dpath, 2,
                                                   revs->dense_combined_merges,
                                                   revs);
-                               free(combine.p.path);
+                               free(dpath);
                                continue;
                        }
-                       free(combine.p.path);
+                       free(dpath);
+                       dpath = NULL;
 
                        /*
                         * Show the diff for the 'ce' if we found the one
                         * from the desired stage.
                         */
-                       diff_unmerge(&revs->diffopt, ce->name);
+                       diff_unmerge(&revs->diffopt, ce->name, 0, null_sha1);
                        if (ce_stage(ce) != diff_unmerged_stage)
                                continue;
                }
@@ -111,16 +446,11 @@ int run_diff_files(struct rev_info *revs, int silent_on_removed)
                                       ce->sha1, ce->name, NULL);
                        continue;
                }
-               changed = ce_match_stat(ce, &st, 0);
-               if (!changed && !revs->diffopt.find_copies_harder)
+               changed = ce_match_stat(ce, &st, ce_option);
+               if (!changed && !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
                        continue;
                oldmode = ntohl(ce->ce_mode);
-
-               newmode = canon_mode(st.st_mode);
-               if (!trust_executable_bit &&
-                   S_ISREG(newmode) && S_ISREG(oldmode) &&
-                   ((newmode ^ oldmode) == 0111))
-                       newmode = oldmode;
+               newmode = ntohl(ce_mode_from_stat(ce, st.st_mode));
                diff_change(&revs->diffopt, oldmode, newmode,
                            ce->sha1, (changed ? null_sha1 : ce->sha1),
                            ce->name, NULL);
@@ -167,9 +497,7 @@ static int get_stat_data(struct cache_entry *ce,
                }
                changed = ce_match_stat(ce, &st, 0);
                if (changed) {
-                       mode = create_ce_mode(st.st_mode);
-                       if (!trust_executable_bit && S_ISREG(st.st_mode))
-                               mode = ce->ce_mode;
+                       mode = ce_mode_from_stat(ce, st.st_mode);
                        sha1 = no_sha1;
                }
        }
@@ -211,9 +539,34 @@ static int show_modified(struct rev_info *revs,
                return -1;
        }
 
+       if (revs->combine_merges && !cached &&
+           (hashcmp(sha1, old->sha1) || hashcmp(old->sha1, new->sha1))) {
+               struct combine_diff_path *p;
+               int pathlen = ce_namelen(new);
+
+               p = xmalloc(combine_diff_path_size(2, pathlen));
+               p->path = (char *) &p->parent[2];
+               p->next = NULL;
+               p->len = pathlen;
+               memcpy(p->path, new->name, pathlen);
+               p->path[pathlen] = 0;
+               p->mode = ntohl(mode);
+               hashclr(p->sha1);
+               memset(p->parent, 0, 2 * sizeof(struct combine_diff_parent));
+               p->parent[0].status = DIFF_STATUS_MODIFIED;
+               p->parent[0].mode = ntohl(new->ce_mode);
+               hashcpy(p->parent[0].sha1, new->sha1);
+               p->parent[1].status = DIFF_STATUS_MODIFIED;
+               p->parent[1].mode = ntohl(old->ce_mode);
+               hashcpy(p->parent[1].sha1, old->sha1);
+               show_combined_diff(p, 2, revs->dense_combined_merges, revs);
+               free(p);
+               return 0;
+       }
+
        oldmode = old->ce_mode;
-       if (mode == oldmode && !memcmp(sha1, old->sha1, 20) &&
-           !revs->diffopt.find_copies_harder)
+       if (mode == oldmode && !hashcmp(sha1, old->sha1) &&
+           !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
                return 0;
 
        mode = ntohl(mode);
@@ -233,6 +586,10 @@ static int diff_cache(struct rev_info *revs,
                struct cache_entry *ce = *ac;
                int same = (entries > 1) && ce_same_name(ce, ac[1]);
 
+               if (DIFF_OPT_TST(&revs->diffopt, QUIET) &&
+                       DIFF_OPT_TST(&revs->diffopt, HAS_CHANGES))
+                       break;
+
                if (!ce_path_match(ce, pathspec))
                        goto skip_entry;
 
@@ -244,7 +601,7 @@ static int diff_cache(struct rev_info *revs,
                                break;
                        }
                        /* Show difference between old and new */
-                       show_modified(revs,ac[1], ce, 1,
+                       show_modified(revs, ac[1], ce, 1,
                                      cached, match_missing);
                        break;
                case 1:
@@ -270,9 +627,12 @@ static int diff_cache(struct rev_info *revs,
                            !show_modified(revs, ce, ac[1], 0,
                                           cached, match_missing))
                                break;
-                       /* fallthru */
+                       diff_unmerge(&revs->diffopt, ce->name,
+                                    ntohl(ce->ce_mode), ce->sha1);
+                       break;
                case 3:
-                       diff_unmerge(&revs->diffopt, ce->name);
+                       diff_unmerge(&revs->diffopt, ce->name,
+                                    0, null_sha1);
                        break;
 
                default:
@@ -316,21 +676,17 @@ int run_diff_index(struct rev_info *revs, int cached)
        const char *tree_name;
        int match_missing = 0;
 
-       /* 
+       /*
         * Backward compatibility wart - "diff-index -m" does
         * not mean "do not ignore merges", but totally different.
         */
        if (!revs->ignore_merges)
                match_missing = 1;
 
-       if (read_cache() < 0) {
-               perror("read_cache");
-               return -1;
-       }
        mark_merge_entries();
 
-       ent = revs->pending_objects->item;
-       tree_name = revs->pending_objects->name;
+       ent = revs->pending.objects[0].item;
+       tree_name = revs->pending.objects[0].name;
        tree = parse_tree_indirect(ent->sha1);
        if (!tree)
                return error("bad tree object %s", tree_name);
@@ -342,3 +698,44 @@ int run_diff_index(struct rev_info *revs, int cached)
        diff_flush(&revs->diffopt);
        return ret;
 }
+
+int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
+{
+       struct tree *tree;
+       struct rev_info revs;
+       int i;
+       struct cache_entry **dst;
+       struct cache_entry *last = NULL;
+
+       /*
+        * This is used by git-blame to run diff-cache internally;
+        * it potentially needs to repeatedly run this, so we will
+        * start by removing the higher order entries the last round
+        * left behind.
+        */
+       dst = active_cache;
+       for (i = 0; i < active_nr; i++) {
+               struct cache_entry *ce = active_cache[i];
+               if (ce_stage(ce)) {
+                       if (last && !strcmp(ce->name, last->name))
+                               continue;
+                       cache_tree_invalidate_path(active_cache_tree,
+                                                  ce->name);
+                       last = ce;
+                       ce->ce_mode = 0;
+                       ce->ce_flags &= ~htons(CE_STAGEMASK);
+               }
+               *dst++ = ce;
+       }
+       active_nr = dst - active_cache;
+
+       init_revisions(&revs, NULL);
+       revs.prune_data = opt->paths;
+       tree = parse_tree_indirect(tree_sha1);
+       if (!tree)
+               die("bad tree object %s", sha1_to_hex(tree_sha1));
+       if (read_tree(tree, 1, opt->paths))
+               return error("unable to read tree %s", sha1_to_hex(tree_sha1));
+       return diff_cache(&revs, active_cache, active_nr, revs.prune_data,
+                         1, 0);
+}