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-rw-r--r--diff-lib.c738
1 files changed, 738 insertions, 0 deletions
diff --git a/diff-lib.c b/diff-lib.c
new file mode 100644
index 0000000000..7531e20c78
--- /dev/null
+++ b/diff-lib.c
@@ -0,0 +1,738 @@
+/*
+ * Copyright (C) 2005 Junio C Hamano
+ */
+#include "cache.h"
+#include "quote.h"
+#include "commit.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "cache-tree.h"
+#include "path-list.h"
+
+/*
+ * diff-files
+ */
+
+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(xstrdup(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 (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, int *silent)
+{
+ *silent = 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;
+ revs->diffopt.exit_with_status = 1;
+ }
+ else if (!strcmp(argv[1], "-q"))
+ *silent = 1;
+ 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;
+ }
+
+ /*
+ * 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, "-") || path[0] == '/')
+ 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;
+ revs->diffopt.exit_with_status = 1;
+ 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;
+ revs->max_count = -2;
+ return 0;
+}
+
+int run_diff_files_cmd(struct rev_info *revs, int argc, const char **argv)
+{
+ int silent_on_removed;
+
+ if (handle_diff_files_args(revs, argc, argv, &silent_on_removed))
+ return -1;
+
+ if (revs->max_count == -2) {
+ 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, silent_on_removed);
+}
+
+int run_diff_files(struct rev_info *revs, int silent_on_removed)
+{
+ int entries, i;
+ int diff_unmerged_stage = revs->max_count;
+
+ if (diff_unmerged_stage < 0)
+ diff_unmerged_stage = 2;
+ 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 (revs->diffopt.quiet && revs->diffopt.has_changes)
+ break;
+
+ if (!ce_path_match(ce, revs->prune_data))
+ continue;
+
+ if (ce_stage(ce)) {
+ 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]);
+
+ 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 = canon_mode(st.st_mode);
+
+ while (i < entries) {
+ struct cache_entry *nce = active_cache[i];
+ int stage;
+
+ if (strcmp(ce->name, nce->name))
+ break;
+
+ /* Stage #2 (ours) is the first parent,
+ * stage #3 (theirs) is the second.
+ */
+ stage = ce_stage(nce);
+ if (2 <= stage) {
+ int mode = ntohl(nce->ce_mode);
+ num_compare_stages++;
+ hashcpy(dpath->parent[stage-2].sha1, nce->sha1);
+ dpath->parent[stage-2].mode =
+ canon_mode(mode);
+ dpath->parent[stage-2].status =
+ DIFF_STATUS_MODIFIED;
+ }
+
+ /* diff against the proper unmerged stage */
+ if (stage == diff_unmerged_stage)
+ ce = nce;
+ i++;
+ }
+ /*
+ * Compensate for loop update
+ */
+ i--;
+
+ if (revs->combine_merges && num_compare_stages == 2) {
+ show_combined_diff(dpath, 2,
+ revs->dense_combined_merges,
+ revs);
+ free(dpath);
+ continue;
+ }
+ 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, 0, null_sha1);
+ if (ce_stage(ce) != diff_unmerged_stage)
+ continue;
+ }
+
+ if (lstat(ce->name, &st) < 0) {
+ if (errno != ENOENT && errno != ENOTDIR) {
+ perror(ce->name);
+ continue;
+ }
+ if (silent_on_removed)
+ continue;
+ diff_addremove(&revs->diffopt, '-', ntohl(ce->ce_mode),
+ ce->sha1, ce->name, NULL);
+ continue;
+ }
+ changed = ce_match_stat(ce, &st, 0);
+ if (!changed && !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;
+ else if (!has_symlinks &&
+ S_ISREG(newmode) && S_ISLNK(oldmode))
+ newmode = oldmode;
+ diff_change(&revs->diffopt, oldmode, newmode,
+ ce->sha1, (changed ? null_sha1 : ce->sha1),
+ ce->name, NULL);
+
+ }
+ diffcore_std(&revs->diffopt);
+ diff_flush(&revs->diffopt);
+ return 0;
+}
+
+/*
+ * diff-index
+ */
+
+/* A file entry went away or appeared */
+static void diff_index_show_file(struct rev_info *revs,
+ const char *prefix,
+ struct cache_entry *ce,
+ unsigned char *sha1, unsigned int mode)
+{
+ diff_addremove(&revs->diffopt, prefix[0], ntohl(mode),
+ sha1, ce->name, NULL);
+}
+
+static int get_stat_data(struct cache_entry *ce,
+ unsigned char **sha1p,
+ unsigned int *modep,
+ int cached, int match_missing)
+{
+ unsigned char *sha1 = ce->sha1;
+ unsigned int mode = ce->ce_mode;
+
+ if (!cached) {
+ static unsigned char no_sha1[20];
+ int changed;
+ struct stat st;
+ if (lstat(ce->name, &st) < 0) {
+ if (errno == ENOENT && match_missing) {
+ *sha1p = sha1;
+ *modep = mode;
+ return 0;
+ }
+ return -1;
+ }
+ changed = ce_match_stat(ce, &st, 0);
+ if (changed) {
+ mode = ce_mode_from_stat(ce, st.st_mode);
+ sha1 = no_sha1;
+ }
+ }
+
+ *sha1p = sha1;
+ *modep = mode;
+ return 0;
+}
+
+static void show_new_file(struct rev_info *revs,
+ struct cache_entry *new,
+ int cached, int match_missing)
+{
+ 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, cached, match_missing) < 0)
+ return;
+
+ diff_index_show_file(revs, "+", new, sha1, mode);
+}
+
+static int show_modified(struct rev_info *revs,
+ struct cache_entry *old,
+ struct cache_entry *new,
+ int report_missing,
+ int cached, int match_missing)
+{
+ unsigned int mode, oldmode;
+ unsigned char *sha1;
+
+ if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
+ if (report_missing)
+ diff_index_show_file(revs, "-", old,
+ old->sha1, old->ce_mode);
+ 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 && !hashcmp(sha1, old->sha1) &&
+ !revs->diffopt.find_copies_harder)
+ return 0;
+
+ mode = ntohl(mode);
+ oldmode = ntohl(oldmode);
+
+ diff_change(&revs->diffopt, oldmode, mode,
+ old->sha1, sha1, old->name, NULL);
+ return 0;
+}
+
+static int diff_cache(struct rev_info *revs,
+ struct cache_entry **ac, int entries,
+ const char **pathspec,
+ int cached, int match_missing)
+{
+ while (entries) {
+ struct cache_entry *ce = *ac;
+ int same = (entries > 1) && ce_same_name(ce, ac[1]);
+
+ if (revs->diffopt.quiet && revs->diffopt.has_changes)
+ break;
+
+ 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(revs, ce, cached, match_missing);
+ break;
+ }
+ /* Show difference between old and new */
+ show_modified(revs, ac[1], ce, 1,
+ cached, match_missing);
+ break;
+ case 1:
+ /* No stage 3 (merge) entry?
+ * That means it's been deleted.
+ */
+ if (!same) {
+ diff_index_show_file(revs, "-", 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 &&
+ !show_modified(revs, ce, ac[1], 0,
+ cached, match_missing))
+ break;
+ diff_unmerge(&revs->diffopt, ce->name,
+ ntohl(ce->ce_mode), ce->sha1);
+ break;
+ case 3:
+ diff_unmerge(&revs->diffopt, ce->name,
+ 0, null_sha1);
+ 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);
+ }
+}
+
+int run_diff_index(struct rev_info *revs, int cached)
+{
+ int ret;
+ struct object *ent;
+ struct tree *tree;
+ 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;
+
+ mark_merge_entries();
+
+ 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);
+ if (read_tree(tree, 1, revs->prune_data))
+ return error("unable to read tree object %s", tree_name);
+ ret = diff_cache(revs, active_cache, active_nr, revs->prune_data,
+ cached, match_missing);
+ diffcore_std(&revs->diffopt);
+ 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);
+}
generated by cgit v1.2.3 (git 2.46.0) at 2025-10-31 19:51:27 +0000