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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 09:49:36 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-27 09:49:36 +0000
commit5ec6074f0633939fd17d94111d10c6c6b062978c (patch)
treebfaa17b5a64abc66c918e9c70969e519d9e1df8e /builtin/diff.c
parentInitial commit. (diff)
downloadgit-upstream.tar.xz
git-upstream.zip
Adding upstream version 1:2.30.2.upstream/1%2.30.2upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'builtin/diff.c')
-rw-r--r--builtin/diff.c594
1 files changed, 594 insertions, 0 deletions
diff --git a/builtin/diff.c b/builtin/diff.c
new file mode 100644
index 0000000..780c338
--- /dev/null
+++ b/builtin/diff.c
@@ -0,0 +1,594 @@
+/*
+ * Builtin "git diff"
+ *
+ * Copyright (c) 2006 Junio C Hamano
+ */
+#define USE_THE_INDEX_COMPATIBILITY_MACROS
+#include "cache.h"
+#include "config.h"
+#include "ewah/ewok.h"
+#include "lockfile.h"
+#include "color.h"
+#include "commit.h"
+#include "blob.h"
+#include "tag.h"
+#include "diff.h"
+#include "diffcore.h"
+#include "revision.h"
+#include "log-tree.h"
+#include "builtin.h"
+#include "submodule.h"
+#include "oid-array.h"
+
+#define DIFF_NO_INDEX_EXPLICIT 1
+#define DIFF_NO_INDEX_IMPLICIT 2
+
+static const char builtin_diff_usage[] =
+"git diff [<options>] [<commit>] [--] [<path>...]\n"
+" or: git diff [<options>] --cached [<commit>] [--] [<path>...]\n"
+" or: git diff [<options>] <commit> [--merge-base] [<commit>...] <commit> [--] [<path>...]\n"
+" or: git diff [<options>] <commit>...<commit>] [--] [<path>...]\n"
+" or: git diff [<options>] <blob> <blob>]\n"
+" or: git diff [<options>] --no-index [--] <path> <path>]\n"
+COMMON_DIFF_OPTIONS_HELP;
+
+static const char *blob_path(struct object_array_entry *entry)
+{
+ return entry->path ? entry->path : entry->name;
+}
+
+static void stuff_change(struct diff_options *opt,
+ unsigned old_mode, unsigned new_mode,
+ const struct object_id *old_oid,
+ const struct object_id *new_oid,
+ int old_oid_valid,
+ int new_oid_valid,
+ const char *old_path,
+ const char *new_path)
+{
+ struct diff_filespec *one, *two;
+
+ if (!is_null_oid(old_oid) && !is_null_oid(new_oid) &&
+ oideq(old_oid, new_oid) && (old_mode == new_mode))
+ return;
+
+ if (opt->flags.reverse_diff) {
+ SWAP(old_mode, new_mode);
+ SWAP(old_oid, new_oid);
+ SWAP(old_path, new_path);
+ }
+
+ if (opt->prefix &&
+ (strncmp(old_path, opt->prefix, opt->prefix_length) ||
+ strncmp(new_path, opt->prefix, opt->prefix_length)))
+ return;
+
+ one = alloc_filespec(old_path);
+ two = alloc_filespec(new_path);
+ fill_filespec(one, old_oid, old_oid_valid, old_mode);
+ fill_filespec(two, new_oid, new_oid_valid, new_mode);
+
+ diff_queue(&diff_queued_diff, one, two);
+}
+
+static int builtin_diff_b_f(struct rev_info *revs,
+ int argc, const char **argv,
+ struct object_array_entry **blob)
+{
+ /* Blob vs file in the working tree*/
+ struct stat st;
+ const char *path;
+
+ if (argc > 1)
+ usage(builtin_diff_usage);
+
+ GUARD_PATHSPEC(&revs->prune_data, PATHSPEC_FROMTOP | PATHSPEC_LITERAL);
+ path = revs->prune_data.items[0].match;
+
+ if (lstat(path, &st))
+ die_errno(_("failed to stat '%s'"), path);
+ if (!(S_ISREG(st.st_mode) || S_ISLNK(st.st_mode)))
+ die(_("'%s': not a regular file or symlink"), path);
+
+ diff_set_mnemonic_prefix(&revs->diffopt, "o/", "w/");
+
+ if (blob[0]->mode == S_IFINVALID)
+ blob[0]->mode = canon_mode(st.st_mode);
+
+ stuff_change(&revs->diffopt,
+ blob[0]->mode, canon_mode(st.st_mode),
+ &blob[0]->item->oid, &null_oid,
+ 1, 0,
+ blob[0]->path ? blob[0]->path : path,
+ path);
+ diffcore_std(&revs->diffopt);
+ diff_flush(&revs->diffopt);
+ return 0;
+}
+
+static int builtin_diff_blobs(struct rev_info *revs,
+ int argc, const char **argv,
+ struct object_array_entry **blob)
+{
+ const unsigned mode = canon_mode(S_IFREG | 0644);
+
+ if (argc > 1)
+ usage(builtin_diff_usage);
+
+ if (blob[0]->mode == S_IFINVALID)
+ blob[0]->mode = mode;
+
+ if (blob[1]->mode == S_IFINVALID)
+ blob[1]->mode = mode;
+
+ stuff_change(&revs->diffopt,
+ blob[0]->mode, blob[1]->mode,
+ &blob[0]->item->oid, &blob[1]->item->oid,
+ 1, 1,
+ blob_path(blob[0]), blob_path(blob[1]));
+ diffcore_std(&revs->diffopt);
+ diff_flush(&revs->diffopt);
+ return 0;
+}
+
+static int builtin_diff_index(struct rev_info *revs,
+ int argc, const char **argv)
+{
+ unsigned int option = 0;
+ while (1 < argc) {
+ const char *arg = argv[1];
+ if (!strcmp(arg, "--cached") || !strcmp(arg, "--staged"))
+ option |= DIFF_INDEX_CACHED;
+ else if (!strcmp(arg, "--merge-base"))
+ option |= DIFF_INDEX_MERGE_BASE;
+ else
+ usage(builtin_diff_usage);
+ argv++; argc--;
+ }
+ /*
+ * Make sure there is one revision (i.e. pending object),
+ * and there is no revision filtering parameters.
+ */
+ if (revs->pending.nr != 1 ||
+ revs->max_count != -1 || revs->min_age != -1 ||
+ revs->max_age != -1)
+ usage(builtin_diff_usage);
+ if (!(option & DIFF_INDEX_CACHED)) {
+ setup_work_tree();
+ if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
+ perror("read_cache_preload");
+ return -1;
+ }
+ } else if (read_cache() < 0) {
+ perror("read_cache");
+ return -1;
+ }
+ return run_diff_index(revs, option);
+}
+
+static int builtin_diff_tree(struct rev_info *revs,
+ int argc, const char **argv,
+ struct object_array_entry *ent0,
+ struct object_array_entry *ent1)
+{
+ const struct object_id *(oid[2]);
+ struct object_id mb_oid;
+ int merge_base = 0;
+
+ while (1 < argc) {
+ const char *arg = argv[1];
+ if (!strcmp(arg, "--merge-base"))
+ merge_base = 1;
+ else
+ usage(builtin_diff_usage);
+ argv++; argc--;
+ }
+
+ if (merge_base) {
+ diff_get_merge_base(revs, &mb_oid);
+ oid[0] = &mb_oid;
+ oid[1] = &revs->pending.objects[1].item->oid;
+ } else {
+ int swap = 0;
+
+ /*
+ * We saw two trees, ent0 and ent1. If ent1 is uninteresting,
+ * swap them.
+ */
+ if (ent1->item->flags & UNINTERESTING)
+ swap = 1;
+ oid[swap] = &ent0->item->oid;
+ oid[1 - swap] = &ent1->item->oid;
+ }
+ diff_tree_oid(oid[0], oid[1], "", &revs->diffopt);
+ log_tree_diff_flush(revs);
+ return 0;
+}
+
+static int builtin_diff_combined(struct rev_info *revs,
+ int argc, const char **argv,
+ struct object_array_entry *ent,
+ int ents)
+{
+ struct oid_array parents = OID_ARRAY_INIT;
+ int i;
+
+ if (argc > 1)
+ usage(builtin_diff_usage);
+
+ if (!revs->dense_combined_merges && !revs->combine_merges)
+ revs->dense_combined_merges = revs->combine_merges = 1;
+ for (i = 1; i < ents; i++)
+ oid_array_append(&parents, &ent[i].item->oid);
+ diff_tree_combined(&ent[0].item->oid, &parents, revs);
+ oid_array_clear(&parents);
+ return 0;
+}
+
+static void refresh_index_quietly(void)
+{
+ struct lock_file lock_file = LOCK_INIT;
+ int fd;
+
+ fd = hold_locked_index(&lock_file, 0);
+ if (fd < 0)
+ return;
+ discard_cache();
+ read_cache();
+ refresh_cache(REFRESH_QUIET|REFRESH_UNMERGED);
+ repo_update_index_if_able(the_repository, &lock_file);
+}
+
+static int builtin_diff_files(struct rev_info *revs, int argc, const char **argv)
+{
+ unsigned int options = 0;
+
+ 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], "-q"))
+ options |= DIFF_SILENT_ON_REMOVED;
+ else if (!strcmp(argv[1], "-h"))
+ usage(builtin_diff_usage);
+ else
+ return error(_("invalid option: %s"), argv[1]);
+ argv++; argc--;
+ }
+
+ /*
+ * "diff --base" should not combine merges because it was not
+ * asked to. "diff -c" should not densify (if the user wants
+ * dense one, --cc can be explicitly asked for, or just rely
+ * on the default).
+ */
+ if (revs->max_count == -1 && !revs->combine_merges &&
+ (revs->diffopt.output_format & DIFF_FORMAT_PATCH))
+ revs->combine_merges = revs->dense_combined_merges = 1;
+
+ setup_work_tree();
+ if (read_cache_preload(&revs->diffopt.pathspec) < 0) {
+ perror("read_cache_preload");
+ return -1;
+ }
+ return run_diff_files(revs, options);
+}
+
+struct symdiff {
+ struct bitmap *skip;
+ int warn;
+ const char *base, *left, *right;
+};
+
+/*
+ * Check for symmetric-difference arguments, and if present, arrange
+ * everything we need to know to handle them correctly. As a bonus,
+ * weed out all bogus range-based revision specifications, e.g.,
+ * "git diff A..B C..D" or "git diff A..B C" get rejected.
+ *
+ * For an actual symmetric diff, *symdiff is set this way:
+ *
+ * - its skip is non-NULL and marks *all* rev->pending.objects[i]
+ * indices that the caller should ignore (extra merge bases, of
+ * which there might be many, and A in A...B). Note that the
+ * chosen merge base and right side are NOT marked.
+ * - warn is set if there are multiple merge bases.
+ * - base, left, and right point to the names to use in a
+ * warning about multiple merge bases.
+ *
+ * If there is no symmetric diff argument, sym->skip is NULL and
+ * sym->warn is cleared. The remaining fields are not set.
+ */
+static void symdiff_prepare(struct rev_info *rev, struct symdiff *sym)
+{
+ int i, is_symdiff = 0, basecount = 0, othercount = 0;
+ int lpos = -1, rpos = -1, basepos = -1;
+ struct bitmap *map = NULL;
+
+ /*
+ * Use the whence fields to find merge bases and left and
+ * right parts of symmetric difference, so that we do not
+ * depend on the order that revisions are parsed. If there
+ * are any revs that aren't from these sources, we have a
+ * "git diff C A...B" or "git diff A...B C" case. Or we
+ * could even get "git diff A...B C...E", for instance.
+ *
+ * If we don't have just one merge base, we pick one
+ * at random.
+ *
+ * NB: REV_CMD_LEFT, REV_CMD_RIGHT are also used for A..B,
+ * so we must check for SYMMETRIC_LEFT too. The two arrays
+ * rev->pending.objects and rev->cmdline.rev are parallel.
+ */
+ for (i = 0; i < rev->cmdline.nr; i++) {
+ struct object *obj = rev->pending.objects[i].item;
+ switch (rev->cmdline.rev[i].whence) {
+ case REV_CMD_MERGE_BASE:
+ if (basepos < 0)
+ basepos = i;
+ basecount++;
+ break; /* do mark all bases */
+ case REV_CMD_LEFT:
+ if (lpos >= 0)
+ usage(builtin_diff_usage);
+ lpos = i;
+ if (obj->flags & SYMMETRIC_LEFT) {
+ is_symdiff = 1;
+ break; /* do mark A */
+ }
+ continue;
+ case REV_CMD_RIGHT:
+ if (rpos >= 0)
+ usage(builtin_diff_usage);
+ rpos = i;
+ continue; /* don't mark B */
+ case REV_CMD_PARENTS_ONLY:
+ case REV_CMD_REF:
+ case REV_CMD_REV:
+ othercount++;
+ continue;
+ }
+ if (map == NULL)
+ map = bitmap_new();
+ bitmap_set(map, i);
+ }
+
+ /*
+ * Forbid any additional revs for both A...B and A..B.
+ */
+ if (lpos >= 0 && othercount > 0)
+ usage(builtin_diff_usage);
+
+ if (!is_symdiff) {
+ bitmap_free(map);
+ sym->warn = 0;
+ sym->skip = NULL;
+ return;
+ }
+
+ sym->left = rev->pending.objects[lpos].name;
+ sym->right = rev->pending.objects[rpos].name;
+ if (basecount == 0)
+ die(_("%s...%s: no merge base"), sym->left, sym->right);
+ sym->base = rev->pending.objects[basepos].name;
+ bitmap_unset(map, basepos); /* unmark the base we want */
+ sym->warn = basecount > 1;
+ sym->skip = map;
+}
+
+int cmd_diff(int argc, const char **argv, const char *prefix)
+{
+ int i;
+ struct rev_info rev;
+ struct object_array ent = OBJECT_ARRAY_INIT;
+ int blobs = 0, paths = 0;
+ struct object_array_entry *blob[2];
+ int nongit = 0, no_index = 0;
+ int result = 0;
+ struct symdiff sdiff;
+
+ /*
+ * We could get N tree-ish in the rev.pending_objects list.
+ * Also there could be M blobs there, and P pathspecs. --cached may
+ * also be present.
+ *
+ * N=0, M=0:
+ * cache vs files (diff-files)
+ *
+ * N=0, M=0, --cached:
+ * HEAD vs cache (diff-index --cached)
+ *
+ * N=0, M=2:
+ * compare two random blobs. P must be zero.
+ *
+ * N=0, M=1, P=1:
+ * compare a blob with a working tree file.
+ *
+ * N=1, M=0:
+ * tree vs files (diff-index)
+ *
+ * N=1, M=0, --cached:
+ * tree vs cache (diff-index --cached)
+ *
+ * N=2, M=0:
+ * tree vs tree (diff-tree)
+ *
+ * N=0, M=0, P=2:
+ * compare two filesystem entities (aka --no-index).
+ *
+ * Other cases are errors.
+ */
+
+ /* Were we asked to do --no-index explicitly? */
+ for (i = 1; i < argc; i++) {
+ if (!strcmp(argv[i], "--")) {
+ i++;
+ break;
+ }
+ if (!strcmp(argv[i], "--no-index"))
+ no_index = DIFF_NO_INDEX_EXPLICIT;
+ if (argv[i][0] != '-')
+ break;
+ }
+
+ prefix = setup_git_directory_gently(&nongit);
+
+ if (!no_index) {
+ /*
+ * Treat git diff with at least one path outside of the
+ * repo the same as if the command would have been executed
+ * outside of a git repository. In this case it behaves
+ * the same way as "git diff --no-index <a> <b>", which acts
+ * as a colourful "diff" replacement.
+ */
+ if (nongit || ((argc == i + 2) &&
+ (!path_inside_repo(prefix, argv[i]) ||
+ !path_inside_repo(prefix, argv[i + 1]))))
+ no_index = DIFF_NO_INDEX_IMPLICIT;
+ }
+
+ init_diff_ui_defaults();
+ git_config(git_diff_ui_config, NULL);
+ precompose_argv(argc, argv);
+
+ repo_init_revisions(the_repository, &rev, prefix);
+
+ /* Set up defaults that will apply to both no-index and regular diffs. */
+ rev.diffopt.stat_width = -1;
+ rev.diffopt.stat_graph_width = -1;
+ rev.diffopt.flags.allow_external = 1;
+ rev.diffopt.flags.allow_textconv = 1;
+
+ /* If this is a no-index diff, just run it and exit there. */
+ if (no_index)
+ exit(diff_no_index(&rev, no_index == DIFF_NO_INDEX_IMPLICIT,
+ argc, argv));
+
+
+ /*
+ * Otherwise, we are doing the usual "git" diff; set up any
+ * further defaults that apply to regular diffs.
+ */
+ rev.diffopt.skip_stat_unmatch = !!diff_auto_refresh_index;
+
+ /*
+ * Default to intent-to-add entries invisible in the
+ * index. This makes them show up as new files in diff-files
+ * and not at all in diff-cached.
+ */
+ rev.diffopt.ita_invisible_in_index = 1;
+
+ if (nongit)
+ die(_("Not a git repository"));
+ argc = setup_revisions(argc, argv, &rev, NULL);
+ if (!rev.diffopt.output_format) {
+ rev.diffopt.output_format = DIFF_FORMAT_PATCH;
+ diff_setup_done(&rev.diffopt);
+ }
+
+ rev.diffopt.flags.recursive = 1;
+
+ setup_diff_pager(&rev.diffopt);
+
+ /*
+ * Do we have --cached and not have a pending object, then
+ * default to HEAD by hand. Eek.
+ */
+ if (!rev.pending.nr) {
+ int i;
+ for (i = 1; i < argc; i++) {
+ const char *arg = argv[i];
+ if (!strcmp(arg, "--"))
+ break;
+ else if (!strcmp(arg, "--cached") ||
+ !strcmp(arg, "--staged")) {
+ add_head_to_pending(&rev);
+ if (!rev.pending.nr) {
+ struct tree *tree;
+ tree = lookup_tree(the_repository,
+ the_repository->hash_algo->empty_tree);
+ add_pending_object(&rev, &tree->object, "HEAD");
+ }
+ break;
+ }
+ }
+ }
+
+ symdiff_prepare(&rev, &sdiff);
+ for (i = 0; i < rev.pending.nr; i++) {
+ struct object_array_entry *entry = &rev.pending.objects[i];
+ struct object *obj = entry->item;
+ const char *name = entry->name;
+ int flags = (obj->flags & UNINTERESTING);
+ if (!obj->parsed)
+ obj = parse_object(the_repository, &obj->oid);
+ obj = deref_tag(the_repository, obj, NULL, 0);
+ if (!obj)
+ die(_("invalid object '%s' given."), name);
+ if (obj->type == OBJ_COMMIT)
+ obj = &get_commit_tree(((struct commit *)obj))->object;
+
+ if (obj->type == OBJ_TREE) {
+ if (sdiff.skip && bitmap_get(sdiff.skip, i))
+ continue;
+ obj->flags |= flags;
+ add_object_array(obj, name, &ent);
+ } else if (obj->type == OBJ_BLOB) {
+ if (2 <= blobs)
+ die(_("more than two blobs given: '%s'"), name);
+ blob[blobs] = entry;
+ blobs++;
+
+ } else {
+ die(_("unhandled object '%s' given."), name);
+ }
+ }
+ if (rev.prune_data.nr)
+ paths += rev.prune_data.nr;
+
+ /*
+ * Now, do the arguments look reasonable?
+ */
+ if (!ent.nr) {
+ switch (blobs) {
+ case 0:
+ result = builtin_diff_files(&rev, argc, argv);
+ break;
+ case 1:
+ if (paths != 1)
+ usage(builtin_diff_usage);
+ result = builtin_diff_b_f(&rev, argc, argv, blob);
+ break;
+ case 2:
+ if (paths)
+ usage(builtin_diff_usage);
+ result = builtin_diff_blobs(&rev, argc, argv, blob);
+ break;
+ default:
+ usage(builtin_diff_usage);
+ }
+ }
+ else if (blobs)
+ usage(builtin_diff_usage);
+ else if (ent.nr == 1)
+ result = builtin_diff_index(&rev, argc, argv);
+ else if (ent.nr == 2) {
+ if (sdiff.warn)
+ warning(_("%s...%s: multiple merge bases, using %s"),
+ sdiff.left, sdiff.right, sdiff.base);
+ result = builtin_diff_tree(&rev, argc, argv,
+ &ent.objects[0], &ent.objects[1]);
+ } else
+ result = builtin_diff_combined(&rev, argc, argv,
+ ent.objects, ent.nr);
+ result = diff_result_code(&rev.diffopt, result);
+ if (1 < rev.diffopt.skip_stat_unmatch)
+ refresh_index_quietly();
+ UNLEAK(rev);
+ UNLEAK(ent);
+ UNLEAK(blob);
+ return result;
+}