X-Git-Url: https://git.octo.it/?a=blobdiff_plain;f=diff.c;h=ababcaa0e663254bf4d18adbb5fb0db3ac80f202;hb=f7c1512af8ff4f821c530f9a4bc8f8ff25733d51;hp=a237311d7a7358fca67633d648eaa5d257f87755;hpb=5d728c8411a092f80171f787b5409d98978690c7;p=git.git

diff --git a/diff.c b/diff.c
index a237311d..ababcaa0 100644
--- a/diff.c
+++ b/diff.c
@@ -4,11 +4,17 @@
 #include <sys/types.h>
 #include <sys/wait.h>
 #include <signal.h>
-#include <limits.h>
 #include "cache.h"
 #include "diff.h"
+#include "diffcore.h"
 
 static const char *diff_opts = "-pu";
+static unsigned char null_sha1[20] = { 0, };
+
+static int reverse_diff;
+static int generate_patch;
+static int line_termination = '\n';
+static int inter_name_termination = '\t';
 
 static const char *external_diff(void)
 {
@@ -53,7 +59,7 @@ static char *sq_expand(const char *src)
 	const char *cp;
 	char *bp;
 
-	/* count bytes needed to store the quoted string. */ 
+	/* count bytes needed to store the quoted string. */
 	for (cnt = 1, cp = src; *cp; cnt++, cp++)
 		if (*cp == '\'')
 			cnt += 3;
@@ -73,31 +79,35 @@ static char *sq_expand(const char *src)
 }
 
 static struct diff_tempfile {
-	const char *name;
+	const char *name; /* filename external diff should read from */
 	char hex[41];
 	char mode[10];
 	char tmp_path[50];
 } diff_temp[2];
 
-static void builtin_diff(const char *name,
-			 struct diff_tempfile *temp)
+static void builtin_diff(const char *name_a,
+			 const char *name_b,
+			 struct diff_tempfile *temp,
+			 const char *xfrm_msg)
 {
-	int i, next_at;
-	const char *git_prefix = "# mode: ";
+	int i, next_at, cmd_size;
 	const char *diff_cmd = "diff -L'%s%s' -L'%s%s'";
 	const char *diff_arg  = "'%s' '%s'||:"; /* "||:" is to return 0 */
 	const char *input_name_sq[2];
 	const char *path0[2];
 	const char *path1[2];
-	const char *name_sq = sq_expand(name);
+	const char *name_sq[2];
 	char *cmd;
-	
+
+	name_sq[0] = sq_expand(name_a);
+	name_sq[1] = sq_expand(name_b);
+
 	/* diff_cmd and diff_arg have 6 %s in total which makes
 	 * the sum of these strings 12 bytes larger than required.
 	 * we use 2 spaces around diff-opts, and we need to count
 	 * terminating NUL, so we subtract 9 here.
 	 */
-	int cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
+	cmd_size = (strlen(diff_cmd) + strlen(diff_opts) +
 			strlen(diff_arg) - 9);
 	for (i = 0; i < 2; i++) {
 		input_name_sq[i] = sq_expand(temp[i].name);
@@ -106,7 +116,7 @@ static void builtin_diff(const char *name,
 			path1[i] = "";
 		} else {
 			path0[i] = i ? "b/" : "a/";
-			path1[i] = name_sq;
+			path1[i] = name_sq[i];
 		}
 		cmd_size += (strlen(path0[i]) + strlen(path1[i]) +
 			     strlen(input_name_sq[i]));
@@ -123,14 +133,18 @@ static void builtin_diff(const char *name,
 	next_at += snprintf(cmd+next_at, cmd_size-next_at,
 			    diff_arg, input_name_sq[0], input_name_sq[1]);
 
+	printf("diff --git a/%s b/%s\n", name_a, name_b);
 	if (!path1[0][0])
-		printf("%s. %s %s\n", git_prefix, temp[1].mode, name);
+		printf("new file mode %s\n", temp[1].mode);
 	else if (!path1[1][0])
-		printf("%s%s . %s\n", git_prefix, temp[0].mode, name);
+		printf("deleted file mode %s\n", temp[0].mode);
 	else {
-		if (strcmp(temp[0].mode, temp[1].mode))
-			printf("%s%s %s %s\n", git_prefix,
-			       temp[0].mode, temp[1].mode, name);
+		if (strcmp(temp[0].mode, temp[1].mode)) {
+			printf("old mode %s\n", temp[0].mode);
+			printf("new mode %s\n", temp[1].mode);
+		}
+		if (xfrm_msg && xfrm_msg[0])
+			fputs(xfrm_msg, stdout);
 
 		if (strncmp(temp[0].mode, temp[1].mode, 3))
 			/* we do not run diff between different kind
@@ -142,6 +156,31 @@ static void builtin_diff(const char *name,
 	execlp("/bin/sh","sh", "-c", cmd, NULL);
 }
 
+struct diff_filespec *alloc_filespec(const char *path)
+{
+	int namelen = strlen(path);
+	struct diff_filespec *spec = xmalloc(sizeof(*spec) + namelen + 1);
+	spec->path = (char *)(spec + 1);
+	strcpy(spec->path, path);
+	spec->should_free = spec->should_munmap = 0;
+	spec->xfrm_flags = 0;
+	spec->size = 0;
+	spec->data = NULL;
+	spec->mode = 0;
+	memset(spec->sha1, 0, 20);
+	return spec;
+}
+
+void fill_filespec(struct diff_filespec *spec, const unsigned char *sha1,
+		   unsigned short mode)
+{
+	if (mode) { /* just playing defensive */
+		spec->mode = mode;
+		memcpy(spec->sha1, sha1, 20);
+		spec->sha1_valid = !!memcmp(sha1, null_sha1, 20);
+	}
+}
+
 /*
  * Given a name and sha1 pair, if the dircache tells us the file in
  * the work tree has that object contents, return true, so that
@@ -152,19 +191,19 @@ static int work_tree_matches(const char *name, const unsigned char *sha1)
 	struct cache_entry *ce;
 	struct stat st;
 	int pos, len;
-	
+
 	/* We do not read the cache ourselves here, because the
 	 * benchmark with my previous version that always reads cache
 	 * shows that it makes things worse for diff-tree comparing
 	 * two linux-2.6 kernel trees in an already checked out work
-	 * tree.  This is because most diff-tree comparison deals with
+	 * tree.  This is because most diff-tree comparisons deal with
 	 * only a small number of files, while reading the cache is
 	 * expensive for a large project, and its cost outweighs the
 	 * savings we get by not inflating the object to a temporary
 	 * file.  Practically, this code only helps when we are used
 	 * by diff-cache --cached, which does read the cache before
 	 * calling us.
-	 */ 
+	 */
 	if (!active_cache)
 		return 0;
 
@@ -174,13 +213,86 @@ static int work_tree_matches(const char *name, const unsigned char *sha1)
 		return 0;
 	ce = active_cache[pos];
 	if ((lstat(name, &st) < 0) ||
-	    !S_ISREG(st.st_mode) ||
+	    !S_ISREG(st.st_mode) || /* careful! */
 	    ce_match_stat(ce, &st) ||
 	    memcmp(sha1, ce->sha1, 20))
 		return 0;
+	/* we return 1 only when we can stat, it is a regular file,
+	 * stat information matches, and sha1 recorded in the cache
+	 * matches.  I.e. we know the file in the work tree really is
+	 * the same as the <name, sha1> pair.
+	 */
 	return 1;
 }
 
+/*
+ * While doing rename detection and pickaxe operation, we may need to
+ * grab the data for the blob (or file) for our own in-core comparison.
+ * diff_filespec has data and size fields for this purpose.
+ */
+int diff_populate_filespec(struct diff_filespec *s)
+{
+	int err = 0;
+	if (!DIFF_FILE_VALID(s))
+		die("internal error: asking to populate invalid file.");
+	if (S_ISDIR(s->mode))
+		return -1;
+
+	if (s->data)
+		return err;
+	if (!s->sha1_valid ||
+	    work_tree_matches(s->path, s->sha1)) {
+		struct stat st;
+		int fd;
+		if (lstat(s->path, &st) < 0) {
+			if (errno == ENOENT) {
+			err_empty:
+				err = -1;
+			empty:
+				s->data = "";
+				s->size = 0;
+				return err;
+			}
+		}
+		s->size = st.st_size;
+		if (!s->size)
+			goto empty;
+		if (S_ISLNK(st.st_mode)) {
+			int ret;
+			s->data = xmalloc(s->size);
+			s->should_free = 1;
+			ret = readlink(s->path, s->data, s->size);
+			if (ret < 0) {
+				free(s->data);
+				goto err_empty;
+			}
+			return 0;
+		}
+		fd = open(s->path, O_RDONLY);
+		if (fd < 0)
+			goto err_empty;
+		s->data = mmap(NULL, s->size, PROT_READ, MAP_PRIVATE, fd, 0);
+		s->should_munmap = 1;
+		close(fd);
+	}
+	else {
+		char type[20];
+		s->data = read_sha1_file(s->sha1, type, &s->size);
+		s->should_free = 1;
+	}
+	return 0;
+}
+
+void diff_free_filespec_data(struct diff_filespec *s)
+{
+	if (s->should_free)
+		free(s->data);
+	else if (s->should_munmap)
+		munmap(s->data, s->size);
+	s->should_free = s->should_munmap = 0;
+	s->data = NULL;
+}
+
 static void prep_temp_blob(struct diff_tempfile *temp,
 			   void *blob,
 			   unsigned long size,
@@ -204,12 +316,9 @@ static void prep_temp_blob(struct diff_tempfile *temp,
 
 static void prepare_temp_file(const char *name,
 			      struct diff_tempfile *temp,
-			      struct diff_spec *one)
+			      struct diff_filespec *one)
 {
-	static unsigned char null_sha1[20] = { 0, };
-	int use_work_tree = 0;
-
-	if (!one->file_valid) {
+	if (!DIFF_FILE_VALID(one)) {
 	not_a_valid_file:
 		/* A '-' entry produces this for file-2, and
 		 * a '+' entry produces this for file-1.
@@ -220,18 +329,13 @@ static void prepare_temp_file(const char *name,
 		return;
 	}
 
-	if (one->sha1_valid &&
-	    (!memcmp(one->blob_sha1, null_sha1, sizeof(null_sha1)) ||
-	     work_tree_matches(name, one->blob_sha1)))
-		use_work_tree = 1;
-
-	if (!one->sha1_valid || use_work_tree) {
+	if (!one->sha1_valid ||
+	    work_tree_matches(name, one->sha1)) {
 		struct stat st;
-		temp->name = name;
-		if (lstat(temp->name, &st) < 0) {
+		if (lstat(name, &st) < 0) {
 			if (errno == ENOENT)
 				goto not_a_valid_file;
-			die("stat(%s): %s", temp->name, strerror(errno));
+			die("stat(%s): %s", name, strerror(errno));
 		}
 		if (S_ISLNK(st.st_mode)) {
 			int ret;
@@ -243,31 +347,27 @@ static void prepare_temp_file(const char *name,
 				die("readlink(%s)", name);
 			prep_temp_blob(temp, buf, st.st_size,
 				       (one->sha1_valid ?
-					one->blob_sha1 : null_sha1),
+					one->sha1 : null_sha1),
 				       (one->sha1_valid ?
 					one->mode : S_IFLNK));
 		}
 		else {
+			/* we can borrow from the file in the work tree */
+			temp->name = name;
 			if (!one->sha1_valid)
 				strcpy(temp->hex, sha1_to_hex(null_sha1));
 			else
-				strcpy(temp->hex, sha1_to_hex(one->blob_sha1));
+				strcpy(temp->hex, sha1_to_hex(one->sha1));
 			sprintf(temp->mode, "%06o",
 				S_IFREG |ce_permissions(st.st_mode));
 		}
 		return;
 	}
 	else {
-		void *blob;
-		char type[20];
-		unsigned long size;
-
-		blob = read_sha1_file(one->blob_sha1, type, &size);
-		if (!blob || strcmp(type, "blob"))
-			die("unable to read blob object for %s (%s)",
-			    name, sha1_to_hex(one->blob_sha1));
-		prep_temp_blob(temp, blob, size, one->blob_sha1, one->mode);
-		free(blob);
+		if (diff_populate_filespec(one))
+			die("cannot read data blob for %s", one->path);
+		prep_temp_blob(temp, one->data, one->size,
+			       one->sha1, one->mode);
 	}
 }
 
@@ -290,12 +390,14 @@ static void remove_tempfile_on_signal(int signo)
 /* An external diff command takes:
  *
  * diff-cmd name infile1 infile1-sha1 infile1-mode \
- *               infile2 infile2-sha1 infile2-mode.
+ *               infile2 infile2-sha1 infile2-mode [ rename-to ]
  *
  */
-void run_external_diff(const char *name,
-		       struct diff_spec *one,
-		       struct diff_spec *two)
+static void run_external_diff(const char *name,
+			      const char *other,
+			      struct diff_filespec *one,
+			      struct diff_filespec *two,
+			      const char *xfrm_msg)
 {
 	struct diff_tempfile *temp = diff_temp;
 	pid_t pid;
@@ -304,7 +406,7 @@ void run_external_diff(const char *name,
 
 	if (one && two) {
 		prepare_temp_file(name, &temp[0], one);
-		prepare_temp_file(name, &temp[1], two);
+		prepare_temp_file(other ? : name, &temp[1], two);
 		if (! atexit_asked &&
 		    (temp[0].name == temp[0].tmp_path ||
 		     temp[1].name == temp[1].tmp_path)) {
@@ -321,12 +423,24 @@ void run_external_diff(const char *name,
 	if (!pid) {
 		const char *pgm = external_diff();
 		if (pgm) {
-			if (one && two)
-				execlp(pgm, pgm,
-				       name,
-				       temp[0].name, temp[0].hex, temp[0].mode,
-				       temp[1].name, temp[1].hex, temp[1].mode,
-				       NULL);
+			if (one && two) {
+				const char *exec_arg[10];
+				const char **arg = &exec_arg[0];
+				*arg++ = pgm;
+				*arg++ = name;
+				*arg++ = temp[0].name;
+				*arg++ = temp[0].hex;
+				*arg++ = temp[0].mode;
+				*arg++ = temp[1].name;
+				*arg++ = temp[1].hex;
+				*arg++ = temp[1].mode;
+				if (other) {
+					*arg++ = other;
+					*arg++ = xfrm_msg;
+				}
+				*arg = NULL;
+				execvp(pgm, (char *const*) exec_arg);
+			}
 			else
 				execlp(pgm, pgm, name, NULL);
 		}
@@ -334,7 +448,7 @@ void run_external_diff(const char *name,
 		 * otherwise we use the built-in one.
 		 */
 		if (one && two)
-			builtin_diff(name, temp);
+			builtin_diff(name, other ? : name, temp, xfrm_msg);
 		else
 			printf("* Unmerged path %s\n", name);
 		exit(0);
@@ -357,53 +471,334 @@ void run_external_diff(const char *name,
 	remove_tempfile();
 }
 
+void diff_setup(int reverse_diff_)
+{
+	reverse_diff = reverse_diff_;
+}
+
+struct diff_queue_struct diff_queued_diff;
+
+void diff_q(struct diff_queue_struct *queue, struct diff_filepair *dp)
+{
+	if (queue->alloc <= queue->nr) {
+		queue->alloc = alloc_nr(queue->alloc);
+		queue->queue = xrealloc(queue->queue,
+					sizeof(dp) * queue->alloc);
+	}
+	queue->queue[queue->nr++] = dp;
+}
+
+struct diff_filepair *diff_queue(struct diff_queue_struct *queue,
+				 struct diff_filespec *one,
+				 struct diff_filespec *two)
+{
+	struct diff_filepair *dp = xmalloc(sizeof(*dp));
+	dp->one = one;
+	dp->two = two;
+	dp->score = 0;
+	dp->orig_order = queue->nr;
+	dp->rename_rank = 0;
+	diff_q(queue, dp);
+	return dp;
+}
+
+static void diff_flush_raw(struct diff_filepair *p)
+{
+	if (DIFF_PAIR_UNMERGED(p)) {
+		printf("U %s%c", p->one->path, line_termination);
+		return;
+	}
+	printf(":%06o %06o %s ",
+	       p->one->mode, p->two->mode, sha1_to_hex(p->one->sha1));
+	printf("%s%c%s%c%s%c",
+	       sha1_to_hex(p->two->sha1), inter_name_termination,
+	       p->one->path, inter_name_termination,
+	       p->two->path, line_termination);
+}
+
+int diff_unmodified_pair(struct diff_filepair *p)
+{
+	/* This function is written stricter than necessary to support
+	 * the currently implemented transformers, but the idea is to
+	 * let transformers to produce diff_filepairs any way they want,
+	 * and filter and clean them up here before producing the output.
+	 */
+	struct diff_filespec *one, *two;
+
+	if (DIFF_PAIR_UNMERGED(p))
+		return 0; /* unmerged is interesting */
+
+	one = p->one;
+	two = p->two;
+
+	/* deletion, addition, mode change and renames are all interesting. */
+	if (DIFF_FILE_VALID(one) != DIFF_FILE_VALID(two) ||
+	    (one->mode != two->mode) ||
+	    strcmp(one->path, two->path))
+		return 0;
+
+	/* both are valid and point at the same path.  that is, we are
+	 * dealing with a change.
+	 */
+	if (one->sha1_valid && two->sha1_valid &&
+	    !memcmp(one->sha1, two->sha1, sizeof(one->sha1)))
+		return 1; /* no change */
+	if (!one->sha1_valid && !two->sha1_valid)
+		return 1; /* both look at the same file on the filesystem. */
+	return 0;
+}
+
+static void diff_flush_patch(struct diff_filepair *p, const char *msg)
+{
+	const char *name, *other;
+
+	/* diffcore_prune() keeps "stay" entries for diff-raw
+	 * copy/rename detection, but when we are generating
+	 * patches we do not need them.
+	 */
+	if (diff_unmodified_pair(p))
+		return;
+
+	name = p->one->path;
+	other = (strcmp(name, p->two->path) ? p->two->path : NULL);
+	if ((DIFF_FILE_VALID(p->one) && S_ISDIR(p->one->mode)) ||
+	    (DIFF_FILE_VALID(p->two) && S_ISDIR(p->two->mode)))
+		return; /* no tree diffs in patch format */ 
+
+	if (DIFF_PAIR_UNMERGED(p))
+		run_external_diff(name, NULL, NULL, NULL, NULL);
+	else
+		run_external_diff(name, other, p->one, p->two, msg);
+}
+
+int diff_needs_to_stay(struct diff_queue_struct *q, int i,
+		       struct diff_filespec *it)
+{
+	/* If it will be used in later entry (either stay or used
+	 * as the source of rename/copy), we need to copy, not rename.
+	 */
+	while (i < q->nr) {
+		struct diff_filepair *p = q->queue[i++];
+		if (!DIFF_FILE_VALID(p->two))
+			continue; /* removed is fine */
+		if (strcmp(p->one->path, it->path))
+			continue; /* not relevant */
+
+		/* p has its src set to *it and it is not a delete;
+		 * it will be used for in-place change, rename/copy,
+		 * or just stays there.  We cannot rename it out.
+		 */
+		return 1;
+	}
+	return 0;
+}
+
+static int diff_used_as_source(struct diff_queue_struct *q, int lim,
+			       struct diff_filespec *it)
+{
+	int i;
+	for (i = 0; i < lim; i++) {
+		struct diff_filepair *p = q->queue[i++];
+		if (!strcmp(p->one->path, it->path))
+			return 1;
+	}
+	return 0;
+}
+
+void diffcore_prune(void)
+{
+	/*
+	 * Although rename/copy detection wants to have "no-change"
+	 * entries fed into them, the downstream do not need to see
+	 * them, unless we had rename/copy for the same path earlier.
+	 * This function removes such entries.
+	 *
+	 * The applications that use rename/copy should:
+	 *
+	 * (1) feed change and "no-change" entries via diff_queue().
+	 * (2) call diffcore_rename, and any other future diffcore_xxx
+	 *     that would benefit by still having "no-change" entries.
+	 * (3) call diffcore_prune
+	 * (4) call other diffcore_xxx that do not need to see
+	 *     "no-change" entries.
+	 * (5) call diff_flush().
+	 */
+	struct diff_queue_struct *q = &diff_queued_diff;
+	struct diff_queue_struct outq;
+	int i;
+
+	outq.queue = NULL;
+	outq.nr = outq.alloc = 0;
+
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filepair *p = q->queue[i];
+		if (!diff_unmodified_pair(p) ||
+		    diff_used_as_source(q, i, p->one))
+			diff_q(&outq, p);
+		else
+			free(p);
+	}
+	free(q->queue);
+	*q = outq;
+	return;
+}
+
+static void diff_flush_one(struct diff_filepair *p, const char *msg)
+{
+	if (generate_patch)
+		diff_flush_patch(p, msg);
+	else
+		diff_flush_raw(p);
+}
+
+int diff_queue_is_empty(void)
+{
+	struct diff_queue_struct *q = &diff_queued_diff;
+	return q->nr == 0;
+}
+
+void diff_flush(int diff_output_style)
+{
+	struct diff_queue_struct *q = &diff_queued_diff;
+	int i;
+
+	generate_patch = 0;
+	switch (diff_output_style) {
+	case DIFF_FORMAT_HUMAN:
+		line_termination = '\n';
+		inter_name_termination = '\t';
+		break;
+	case DIFF_FORMAT_MACHINE:
+		line_termination = inter_name_termination = 0;
+		break;
+	case DIFF_FORMAT_PATCH:
+		generate_patch = 1;
+		break;
+	}
+	for (i = 0; i < q->nr; i++) {
+		char msg_[PATH_MAX*2+200], *msg = NULL;
+		struct diff_filepair *p = q->queue[i];
+		if (strcmp(p->one->path, p->two->path)) {
+			/* This is rename or copy.  Which one is it? */
+			if (diff_needs_to_stay(q, i+1, p->one)) {
+				sprintf(msg_,
+					"similarity index %d%%\n"
+					"copy from %s\n"
+					"copy to %s\n",
+					(int)(0.5 + p->score * 100/MAX_SCORE),
+					p->one->path, p->two->path);
+			}
+			else
+				sprintf(msg_,
+					"similarity index %d%%\n"
+					"rename old %s\n"
+					"rename new %s\n",
+					(int)(0.5 + p->score * 100/MAX_SCORE),
+					p->one->path, p->two->path);
+			msg = msg_;
+		}
+		diff_flush_one(p, msg);
+	}
+
+	for (i = 0; i < q->nr; i++) {
+		struct diff_filepair *p = q->queue[i];
+		diff_free_filespec_data(p->one);
+		diff_free_filespec_data(p->two);
+		free(p);
+	}
+	free(q->queue);
+	q->queue = NULL;
+	q->nr = q->alloc = 0;
+}
+
 void diff_addremove(int addremove, unsigned mode,
 		    const unsigned char *sha1,
 		    const char *base, const char *path)
 {
 	char concatpath[PATH_MAX];
-	struct diff_spec spec[2], *one, *two;
+	struct diff_filespec *one, *two;
+
+	/* This may look odd, but it is a preparation for
+	 * feeding "there are unchanged files which should
+	 * not produce diffs, but when you are doing copy
+	 * detection you would need them, so here they are"
+	 * entries to the diff-core.  They will be prefixed
+	 * with something like '=' or '*' (I haven't decided
+	 * which but should not make any difference).
+	 * Feeding the same new and old to diff_change() 
+	 * also has the same effect.  diffcore_prune() should
+	 * be used to filter uninteresting ones out before the
+	 * final output happens.
+	 */
+	if (reverse_diff)
+		addremove = (addremove == '+' ? '-' :
+			     addremove == '-' ? '+' : addremove);
 
-	memcpy(spec[0].blob_sha1, sha1, 20);
-	spec[0].mode = mode;
-	spec[0].sha1_valid = spec[0].file_valid = 1;
-	spec[1].file_valid = 0;
+	if (!path) path = "";
+	sprintf(concatpath, "%s%s", base, path);
+	one = alloc_filespec(concatpath);
+	two = alloc_filespec(concatpath);
 
-	if (addremove == '+') {
-		one = spec + 1; two = spec;
-	} else {
-		one = spec; two = one + 1;
-	}
-	
-	if (path) {
-		strcpy(concatpath, base);
-		strcat(concatpath, path);
+	if (addremove != '+')
+		fill_filespec(one, sha1, mode);
+	if (addremove != '-')
+		fill_filespec(two, sha1, mode);
+
+	diff_queue(&diff_queued_diff, one, two);
+}
+
+void diff_guif(unsigned old_mode,
+	       unsigned new_mode,
+	       const unsigned char *old_sha1,
+	       const unsigned char *new_sha1,
+	       const char *old_path,
+	       const char *new_path)
+{
+	struct diff_filespec *one, *two;
+
+	if (reverse_diff) {
+		unsigned tmp;
+		const unsigned char *tmp_c;
+		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
+		tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
 	}
-	run_external_diff(path ? concatpath : base, one, two);
+	one = alloc_filespec(old_path);
+	two = alloc_filespec(new_path);
+	if (old_mode)
+		fill_filespec(one, old_sha1, old_mode);
+	if (new_mode)
+		fill_filespec(two, new_sha1, new_mode);
+	diff_queue(&diff_queued_diff, one, two);
 }
 
 void diff_change(unsigned old_mode, unsigned new_mode,
 		 const unsigned char *old_sha1,
 		 const unsigned char *new_sha1,
-		 const char *base, const char *path) {
+		 const char *base, const char *path) 
+{
 	char concatpath[PATH_MAX];
-	struct diff_spec spec[2];
-
-	memcpy(spec[0].blob_sha1, old_sha1, 20);
-	spec[0].mode = old_mode;
-	memcpy(spec[1].blob_sha1, new_sha1, 20);
-	spec[1].mode = new_mode;
-	spec[0].sha1_valid = spec[0].file_valid = 1;
-	spec[1].sha1_valid = spec[1].file_valid = 1;
-
-	if (path) {
-		strcpy(concatpath, base);
-		strcat(concatpath, path);
+	struct diff_filespec *one, *two;
+
+	if (reverse_diff) {
+		unsigned tmp;
+		const unsigned char *tmp_c;
+		tmp = old_mode; old_mode = new_mode; new_mode = tmp;
+		tmp_c = old_sha1; old_sha1 = new_sha1; new_sha1 = tmp_c;
 	}
-	run_external_diff(path ? concatpath : base, &spec[0], &spec[1]);
+	if (!path) path = "";
+	sprintf(concatpath, "%s%s", base, path);
+	one = alloc_filespec(concatpath);
+	two = alloc_filespec(concatpath);
+	fill_filespec(one, old_sha1, old_mode);
+	fill_filespec(two, new_sha1, new_mode);
+
+	diff_queue(&diff_queued_diff, one, two);
 }
 
 void diff_unmerge(const char *path)
 {
-	run_external_diff(path, NULL, NULL);
+	struct diff_filespec *one, *two;
+	one = alloc_filespec(path);
+	two = alloc_filespec(path);
+	diff_queue(&diff_queued_diff, one, two);
 }