1 files changed, 108 insertions, 374 deletions

diff --git a/diff-lib.c b/diff-lib.c
index 94b150e830..e7eaff9a68 100644
--- a/diff-lib.c
+++ b/diff-lib.c
@@ -8,332 +8,52 @@
 #include "diffcore.h"
 #include "revision.h"
 #include "cache-tree.h"
-#include "path-list.h"
 #include "unpack-trees.h"
+#include "refs.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(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 = 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?
+ * Has the work tree entity been removed?
+ *
+ * Return 1 if it was removed from the work tree, 0 if an entity to be
+ * compared with the cache entry ce still exists (the latter includes
+ * the case where a directory that is not a submodule repository
+ * exists for ce that is a submodule -- it is a submodule that is not
+ * checked out).  Return negative for an error.
  */
-static int is_in_index(const char *path)
+static int check_removed(const struct cache_entry *ce, struct stat *st)
 {
-	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)
+	if (lstat(ce->name, st) < 0) {
+		if (errno != ENOENT && errno != ENOTDIR)
+			return -1;
 		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 (has_symlink_leading_path(ce_namelen(ce), ce->name))
+		return 1;
+	if (S_ISDIR(st->st_mode)) {
+		unsigned char sub[20];
 
-	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.
+		 * If ce is already a gitlink, we can have a plain
+		 * directory (i.e. the submodule is not checked out),
+		 * or a checked out submodule.  Either case this is not
+		 * a case where something was removed from the work tree,
+		 * so we will return 0.
+		 *
+		 * Otherwise, if the directory is not a submodule
+		 * repository, that means ce which was a blob turned into
+		 * a directory --- the blob was removed!
 		 */
-		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)
+		if (!S_ISGITLINK(ce->ce_mode) &&
+		    resolve_gitlink_ref(ce->name, "HEAD", sub))
 			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;
@@ -341,10 +61,12 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
 	int silent_on_removed = option & DIFF_SILENT_ON_REMOVED;
 	unsigned ce_option = ((option & DIFF_RACY_IS_MODIFIED)
 			      ? CE_MATCH_RACY_IS_DIRTY : 0);
+	char symcache[PATH_MAX];
 
 	if (diff_unmerged_stage < 0)
 		diff_unmerged_stage = 2;
 	entries = active_nr;
+	symcache[0] = '\0';
 	for (i = 0; i < entries; i++) {
 		struct stat st;
 		unsigned int oldmode, newmode;
@@ -376,16 +98,17 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
 			memset(&(dpath->parent[0]), 0,
 			       sizeof(struct combine_diff_parent)*5);
 
-			if (lstat(ce->name, &st) < 0) {
-				if (errno != ENOENT && errno != ENOTDIR) {
+			changed = check_removed(ce, &st);
+			if (!changed)
+				dpath->mode = ce_mode_from_stat(ce, st.st_mode);
+			else {
+				if (changed < 0) {
 					perror(ce->name);
 					continue;
 				}
 				if (silent_on_removed)
 					continue;
 			}
-			else
-				dpath->mode = ce_mode_from_stat(ce, st.st_mode);
 
 			while (i < entries) {
 				struct cache_entry *nce = active_cache[i];
@@ -438,25 +161,30 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
 
 		if (ce_uptodate(ce))
 			continue;
-		if (lstat(ce->name, &st) < 0) {
-			if (errno != ENOENT && errno != ENOTDIR) {
+
+		changed = check_removed(ce, &st);
+		if (changed) {
+			if (changed < 0) {
 				perror(ce->name);
 				continue;
 			}
 			if (silent_on_removed)
 				continue;
 			diff_addremove(&revs->diffopt, '-', ce->ce_mode,
-				       ce->sha1, ce->name, NULL);
+				       ce->sha1, ce->name);
 			continue;
 		}
 		changed = ce_match_stat(ce, &st, ce_option);
-		if (!changed && !DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
-			continue;
+		if (!changed) {
+			ce_mark_uptodate(ce);
+			if (!DIFF_OPT_TST(&revs->diffopt, FIND_COPIES_HARDER))
+				continue;
+		}
 		oldmode = ce->ce_mode;
 		newmode = ce_mode_from_stat(ce, st.st_mode);
 		diff_change(&revs->diffopt, oldmode, newmode,
 			    ce->sha1, (changed ? null_sha1 : ce->sha1),
-			    ce->name, NULL);
+			    ce->name);
 
 	}
 	diffcore_std(&revs->diffopt);
@@ -468,30 +196,38 @@ int run_diff_files(struct rev_info *revs, unsigned int option)
  * diff-index
  */
 
+struct oneway_unpack_data {
+	struct rev_info *revs;
+	char symcache[PATH_MAX];
+};
+
 /* 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)
+				 const unsigned char *sha1, unsigned int mode)
 {
 	diff_addremove(&revs->diffopt, prefix[0], mode,
-		       sha1, ce->name, NULL);
+		       sha1, ce->name);
 }
 
 static int get_stat_data(struct cache_entry *ce,
-			 unsigned char **sha1p,
+			 const unsigned char **sha1p,
 			 unsigned int *modep,
-			 int cached, int match_missing)
+			 int cached, int match_missing,
+			 struct oneway_unpack_data *cbdata)
 {
-	unsigned char *sha1 = ce->sha1;
+	const 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) {
+		changed = check_removed(ce, &st);
+		if (changed < 0)
+			return -1;
+		else if (changed) {
+			if (match_missing) {
 				*sha1p = sha1;
 				*modep = mode;
 				return 0;
@@ -501,7 +237,7 @@ static int get_stat_data(struct cache_entry *ce,
 		changed = ce_match_stat(ce, &st, 0);
 		if (changed) {
 			mode = ce_mode_from_stat(ce, st.st_mode);
-			sha1 = no_sha1;
+			sha1 = null_sha1;
 		}
 	}
 
@@ -510,32 +246,35 @@ static int get_stat_data(struct cache_entry *ce,
 	return 0;
 }
 
-static void show_new_file(struct rev_info *revs,
+static void show_new_file(struct oneway_unpack_data *cbdata,
 			  struct cache_entry *new,
 			  int cached, int match_missing)
 {
-	unsigned char *sha1;
+	const unsigned char *sha1;
 	unsigned int mode;
+	struct rev_info *revs = cbdata->revs;
 
-	/* New file in the index: it might actually be different in
+	/*
+	 * 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)
+	if (get_stat_data(new, &sha1, &mode, cached, match_missing, cbdata) < 0)
 		return;
 
 	diff_index_show_file(revs, "+", new, sha1, mode);
 }
 
-static int show_modified(struct rev_info *revs,
+static int show_modified(struct oneway_unpack_data *cbdata,
 			 struct cache_entry *old,
 			 struct cache_entry *new,
 			 int report_missing,
 			 int cached, int match_missing)
 {
 	unsigned int mode, oldmode;
-	unsigned char *sha1;
+	const unsigned char *sha1;
+	struct rev_info *revs = cbdata->revs;
 
-	if (get_stat_data(new, &sha1, &mode, cached, match_missing) < 0) {
+	if (get_stat_data(new, &sha1, &mode, cached, match_missing, cbdata) < 0) {
 		if (report_missing)
 			diff_index_show_file(revs, "-", old,
 					     old->sha1, old->ce_mode);
@@ -573,7 +312,7 @@ static int show_modified(struct rev_info *revs,
 		return 0;
 
 	diff_change(&revs->diffopt, oldmode, mode,
-		    old->sha1, sha1, old->name, NULL);
+		    old->sha1, sha1, old->name);
 	return 0;
 }
 
@@ -601,10 +340,10 @@ static void mark_merge_entries(void)
  */
 static void do_oneway_diff(struct unpack_trees_options *o,
 	struct cache_entry *idx,
-	struct cache_entry *tree,
-	int idx_pos, int idx_nr)
+	struct cache_entry *tree)
 {
-	struct rev_info *revs = o->unpack_data;
+	struct oneway_unpack_data *cbdata = o->unpack_data;
+	struct rev_info *revs = cbdata->revs;
 	int match_missing, cached;
 
 	/*
@@ -627,7 +366,7 @@ static void do_oneway_diff(struct unpack_trees_options *o,
 	 * Something added to the tree?
 	 */
 	if (!tree) {
-		show_new_file(revs, idx, cached, match_missing);
+		show_new_file(cbdata, idx, cached, match_missing);
 		return;
 	}
 
@@ -640,35 +379,22 @@ static void do_oneway_diff(struct unpack_trees_options *o,
 	}
 
 	/* Show difference between old and new */
-	show_modified(revs, tree, idx, 1, cached, match_missing);
+	show_modified(cbdata, tree, idx, 1, cached, match_missing);
 }
 
-/*
- * Count how many index entries go with the first one
- */
-static inline int count_skip(const struct cache_entry *src, int pos)
+static inline void skip_same_name(struct cache_entry *ce, struct unpack_trees_options *o)
 {
-	int skip = 1;
-
-	/* We can only have multiple entries if the first one is not stage-0 */
-	if (ce_stage(src)) {
-		struct cache_entry **p = active_cache + pos;
-		int namelen = ce_namelen(src);
-
-		for (;;) {
-			const struct cache_entry *ce;
-			pos++;
-			if (pos >= active_nr)
-				break;
-			ce = *++p;
-			if (ce_namelen(ce) != namelen)
-				break;
-			if (memcmp(ce->name, src->name, namelen))
-				break;
-			skip++;
-		}
+	int len = ce_namelen(ce);
+	const struct index_state *index = o->src_index;
+
+	while (o->pos < index->cache_nr) {
+		struct cache_entry *next = index->cache[o->pos];
+		if (len != ce_namelen(next))
+			break;
+		if (memcmp(ce->name, next->name, len))
+			break;
+		o->pos++;
 	}
-	return skip;
 }
 
 /*
@@ -686,17 +412,15 @@ static inline int count_skip(const struct cache_entry *src, int pos)
  * the fairly complex unpack_trees() semantic requirements, including
  * the skipping, the path matching, the type conflict cases etc.
  */
-static int oneway_diff(struct cache_entry **src,
-	struct unpack_trees_options *o,
-	int index_pos)
+static int oneway_diff(struct cache_entry **src, struct unpack_trees_options *o)
 {
-	int skip = 0;
 	struct cache_entry *idx = src[0];
 	struct cache_entry *tree = src[1];
-	struct rev_info *revs = o->unpack_data;
+	struct oneway_unpack_data *cbdata = o->unpack_data;
+	struct rev_info *revs = cbdata->revs;
 
-	if (index_pos >= 0)
-		skip = count_skip(idx, index_pos);
+	if (idx && ce_stage(idx))
+		skip_same_name(idx, o);
 
 	/*
 	 * Unpack-trees generates a DF/conflict entry if
@@ -708,9 +432,9 @@ static int oneway_diff(struct cache_entry **src,
 		tree = NULL;
 
 	if (ce_path_match(idx ? idx : tree, revs->prune_data))
-		do_oneway_diff(o, idx, tree, index_pos, skip);
+		do_oneway_diff(o, idx, tree);
 
-	return skip;
+	return 0;
 }
 
 int run_diff_index(struct rev_info *revs, int cached)
@@ -720,6 +444,7 @@ int run_diff_index(struct rev_info *revs, int cached)
 	const char *tree_name;
 	struct unpack_trees_options opts;
 	struct tree_desc t;
+	struct oneway_unpack_data unpack_cb;
 
 	mark_merge_entries();
 
@@ -729,12 +454,16 @@ int run_diff_index(struct rev_info *revs, int cached)
 	if (!tree)
 		return error("bad tree object %s", tree_name);
 
+	unpack_cb.revs = revs;
+	unpack_cb.symcache[0] = '\0';
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = 1;
 	opts.index_only = cached;
 	opts.merge = 1;
 	opts.fn = oneway_diff;
-	opts.unpack_data = revs;
+	opts.unpack_data = &unpack_cb;
+	opts.src_index = &the_index;
+	opts.dst_index = NULL;
 
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts))
@@ -754,6 +483,7 @@ int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 	struct cache_entry *last = NULL;
 	struct unpack_trees_options opts;
 	struct tree_desc t;
+	struct oneway_unpack_data unpack_cb;
 
 	/*
 	 * This is used by git-blame to run diff-cache internally;
@@ -782,12 +512,16 @@ int do_diff_cache(const unsigned char *tree_sha1, struct diff_options *opt)
 	if (!tree)
 		die("bad tree object %s", sha1_to_hex(tree_sha1));
 
+	unpack_cb.revs = &revs;
+	unpack_cb.symcache[0] = '\0';
 	memset(&opts, 0, sizeof(opts));
 	opts.head_idx = 1;
 	opts.index_only = 1;
 	opts.merge = 1;
 	opts.fn = oneway_diff;
-	opts.unpack_data = &revs;
+	opts.unpack_data = &unpack_cb;
+	opts.src_index = &the_index;
+	opts.dst_index = &the_index;
 
 	init_tree_desc(&t, tree->buffer, tree->size);
 	if (unpack_trees(1, &t, &opts))