1 files changed, 334 insertions, 27 deletions

diff --git a/diff.c b/diff.c
index afaa648dbb..e16e0bfc0a 100644
--- a/diff.c
+++ b/diff.c
@@ -8,6 +8,7 @@
 #include "quote.h"
 #include "diff.h"
 #include "diffcore.h"
+#include "delta.h"
 #include "xdiff-interface.h"
 
 static int use_size_cache;
@@ -195,6 +196,61 @@ static int fn_out(void *priv, mmbuffer_t *mb, int nbuf)
 	return 0;
 }
 
+static char *pprint_rename(const char *a, const char *b)
+{
+	const char *old = a;
+	const char *new = b;
+	char *name = NULL;
+	int pfx_length, sfx_length;
+	int len_a = strlen(a);
+	int len_b = strlen(b);
+
+	/* Find common prefix */
+	pfx_length = 0;
+	while (*old && *new && *old == *new) {
+		if (*old == '/')
+			pfx_length = old - a + 1;
+		old++;
+		new++;
+	}
+
+	/* Find common suffix */
+	old = a + len_a;
+	new = b + len_b;
+	sfx_length = 0;
+	while (a <= old && b <= new && *old == *new) {
+		if (*old == '/')
+			sfx_length = len_a - (old - a);
+		old--;
+		new--;
+	}
+
+	/*
+	 * pfx{mid-a => mid-b}sfx
+	 * {pfx-a => pfx-b}sfx
+	 * pfx{sfx-a => sfx-b}
+	 * name-a => name-b
+	 */
+	if (pfx_length + sfx_length) {
+		int a_midlen = len_a - pfx_length - sfx_length;
+		int b_midlen = len_b - pfx_length - sfx_length;
+		if (a_midlen < 0) a_midlen = 0;
+		if (b_midlen < 0) b_midlen = 0;
+
+		name = xmalloc(len_a + len_b - pfx_length - sfx_length + 7);
+		sprintf(name, "%.*s{%.*s => %.*s}%s",
+			pfx_length, a,
+			a_midlen, a + pfx_length,
+			b_midlen, b + pfx_length,
+			a + len_a - sfx_length);
+	}
+	else {
+		name = xmalloc(len_a + len_b + 5);
+		sprintf(name, "%s => %s", a, b);
+	}
+	return name;
+}
+
 struct diffstat_t {
 	struct xdiff_emit_state xm;
 
@@ -204,12 +260,14 @@ struct diffstat_t {
 		char *name;
 		unsigned is_unmerged:1;
 		unsigned is_binary:1;
+		unsigned is_renamed:1;
 		unsigned int added, deleted;
 	} **files;
 };
 
 static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
-		const char *name)
+					  const char *name_a,
+					  const char *name_b)
 {
 	struct diffstat_file *x;
 	x = xcalloc(sizeof (*x), 1);
@@ -219,7 +277,12 @@ static struct diffstat_file *diffstat_add(struct diffstat_t *diffstat,
 				diffstat->alloc * sizeof(x));
 	}
 	diffstat->files[diffstat->nr++] = x;
-	x->name = strdup(name);
+	if (name_b) {
+		x->name = pprint_rename(name_a, name_b);
+		x->is_renamed = 1;
+	}
+	else
+		x->name = strdup(name_a);
 	return x;
 }
 
@@ -305,7 +368,8 @@ static void show_stats(struct diffstat_t* data)
 			printf(" %s%-*s |  Unmerged\n", prefix, len, name);
 			goto free_diffstat_file;
 		}
-		else if (added + deleted == 0) {
+		else if (!data->files[i]->is_renamed &&
+			 (added + deleted == 0)) {
 			total_files--;
 			goto free_diffstat_file;
 		}
@@ -333,6 +397,90 @@ static void show_stats(struct diffstat_t* data)
 			total_files, adds, dels);
 }
 
+static unsigned char *deflate_it(char *data,
+				 unsigned long size,
+				 unsigned long *result_size)
+{
+	int bound;
+	unsigned char *deflated;
+	z_stream stream;
+
+	memset(&stream, 0, sizeof(stream));
+	deflateInit(&stream, Z_BEST_COMPRESSION);
+	bound = deflateBound(&stream, size);
+	deflated = xmalloc(bound);
+	stream.next_out = deflated;
+	stream.avail_out = bound;
+
+	stream.next_in = (unsigned char *)data;
+	stream.avail_in = size;
+	while (deflate(&stream, Z_FINISH) == Z_OK)
+		; /* nothing */
+	deflateEnd(&stream);
+	*result_size = stream.total_out;
+	return deflated;
+}
+
+static void emit_binary_diff(mmfile_t *one, mmfile_t *two)
+{
+	void *cp;
+	void *delta;
+	void *deflated;
+	void *data;
+	unsigned long orig_size;
+	unsigned long delta_size;
+	unsigned long deflate_size;
+	unsigned long data_size;
+
+	printf("GIT binary patch\n");
+	/* We could do deflated delta, or we could do just deflated two,
+	 * whichever is smaller.
+	 */
+	delta = NULL;
+	deflated = deflate_it(two->ptr, two->size, &deflate_size);
+	if (one->size && two->size) {
+		delta = diff_delta(one->ptr, one->size,
+				   two->ptr, two->size,
+				   &delta_size, deflate_size);
+		if (delta) {
+			void *to_free = delta;
+			orig_size = delta_size;
+			delta = deflate_it(delta, delta_size, &delta_size);
+			free(to_free);
+		}
+	}
+
+	if (delta && delta_size < deflate_size) {
+		printf("delta %lu\n", orig_size);
+		free(deflated);
+		data = delta;
+		data_size = delta_size;
+	}
+	else {
+		printf("literal %lu\n", two->size);
+		free(delta);
+		data = deflated;
+		data_size = deflate_size;
+	}
+
+	/* emit data encoded in base85 */
+	cp = data;
+	while (data_size) {
+		int bytes = (52 < data_size) ? 52 : data_size;
+		char line[70];
+		data_size -= bytes;
+		if (bytes <= 26)
+			line[0] = bytes + 'A' - 1;
+		else
+			line[0] = bytes - 26 + 'a' - 1;
+		encode_85(line + 1, cp, bytes);
+		cp += bytes;
+		puts(line);
+	}
+	printf("\n");
+	free(data);
+}
+
 #define FIRST_FEW_BYTES 8000
 static int mmfile_is_binary(mmfile_t *mf)
 {
@@ -349,6 +497,7 @@ static void builtin_diff(const char *name_a,
 			 struct diff_filespec *one,
 			 struct diff_filespec *two,
 			 const char *xfrm_msg,
+			 struct diff_options *o,
 			 int complete_rewrite)
 {
 	mmfile_t mf1, mf2;
@@ -393,8 +542,17 @@ static void builtin_diff(const char *name_a,
 	if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 		die("unable to read files to diff");
 
-	if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2))
-		printf("Binary files %s and %s differ\n", lbl[0], lbl[1]);
+	if (mmfile_is_binary(&mf1) || mmfile_is_binary(&mf2)) {
+		/* Quite common confusing case */
+		if (mf1.size == mf2.size &&
+		    !memcmp(mf1.ptr, mf2.ptr, mf1.size))
+			goto free_ab_and_return;
+		if (o->binary)
+			emit_binary_diff(&mf1, &mf2);
+		else
+			printf("Binary files %s and %s differ\n",
+			       lbl[0], lbl[1]);
+	}
 	else {
 		/* Crazy xdl interfaces.. */
 		const char *diffopts = getenv("GIT_DIFF_OPTS");
@@ -405,7 +563,7 @@ static void builtin_diff(const char *name_a,
 
 		ecbdata.label_path = lbl;
 		xpp.flags = XDF_NEED_MINIMAL;
-		xecfg.ctxlen = 3;
+		xecfg.ctxlen = o->context;
 		xecfg.flags = XDL_EMIT_FUNCNAMES;
 		if (!diffopts)
 			;
@@ -425,19 +583,27 @@ static void builtin_diff(const char *name_a,
 }
 
 static void builtin_diffstat(const char *name_a, const char *name_b,
-		struct diff_filespec *one, struct diff_filespec *two,
-		struct diffstat_t *diffstat)
+			     struct diff_filespec *one,
+			     struct diff_filespec *two,
+			     struct diffstat_t *diffstat,
+			     int complete_rewrite)
 {
 	mmfile_t mf1, mf2;
 	struct diffstat_file *data;
 
-	data = diffstat_add(diffstat, name_a ? name_a : name_b);
+	data = diffstat_add(diffstat, name_a, name_b);
 
 	if (!one || !two) {
 		data->is_unmerged = 1;
 		return;
 	}
-
+	if (complete_rewrite) {
+		diff_populate_filespec(one, 0);
+		diff_populate_filespec(two, 0);
+		data->deleted = count_lines(one->data, one->size);
+		data->added = count_lines(two->data, two->size);
+		return;
+	}
 	if (fill_mmfile(&mf1, one) < 0 || fill_mmfile(&mf2, two) < 0)
 		die("unable to read files to diff");
 
@@ -862,6 +1028,7 @@ static void run_diff_cmd(const char *pgm,
 			 struct diff_filespec *one,
 			 struct diff_filespec *two,
 			 const char *xfrm_msg,
+			 struct diff_options *o,
 			 int complete_rewrite)
 {
 	if (pgm) {
@@ -871,7 +1038,7 @@ static void run_diff_cmd(const char *pgm,
 	}
 	if (one && two)
 		builtin_diff(name, other ? other : name,
-			     one, two, xfrm_msg, complete_rewrite);
+			     one, two, xfrm_msg, o, complete_rewrite);
 	else
 		printf("* Unmerged path %s\n", name);
 }
@@ -905,7 +1072,7 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 
 	if (DIFF_PAIR_UNMERGED(p)) {
 		/* unmerged */
-		run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, 0);
+		run_diff_cmd(pgm, p->one->path, NULL, NULL, NULL, NULL, o, 0);
 		return;
 	}
 
@@ -952,14 +1119,12 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 	}
 
 	if (memcmp(one->sha1, two->sha1, 20)) {
-		char one_sha1[41];
 		int abbrev = o->full_index ? 40 : DEFAULT_ABBREV;
-		memcpy(one_sha1, sha1_to_hex(one->sha1), 41);
 
 		len += snprintf(msg + len, sizeof(msg) - len,
 				"index %.*s..%.*s",
-				abbrev, one_sha1, abbrev,
-				sha1_to_hex(two->sha1));
+				abbrev, sha1_to_hex(one->sha1),
+				abbrev, sha1_to_hex(two->sha1));
 		if (one->mode == two->mode)
 			len += snprintf(msg + len, sizeof(msg) - len,
 					" %06o", one->mode);
@@ -977,14 +1142,14 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 		 * needs to be split into deletion and creation.
 		 */
 		struct diff_filespec *null = alloc_filespec(two->path);
-		run_diff_cmd(NULL, name, other, one, null, xfrm_msg, 0);
+		run_diff_cmd(NULL, name, other, one, null, xfrm_msg, o, 0);
 		free(null);
 		null = alloc_filespec(one->path);
-		run_diff_cmd(NULL, name, other, null, two, xfrm_msg, 0);
+		run_diff_cmd(NULL, name, other, null, two, xfrm_msg, o, 0);
 		free(null);
 	}
 	else
-		run_diff_cmd(pgm, name, other, one, two, xfrm_msg,
+		run_diff_cmd(pgm, name, other, one, two, xfrm_msg, o,
 			     complete_rewrite);
 
 	free(name_munged);
@@ -992,14 +1157,15 @@ static void run_diff(struct diff_filepair *p, struct diff_options *o)
 }
 
 static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
-		struct diffstat_t *diffstat)
+			 struct diffstat_t *diffstat)
 {
 	const char *name;
 	const char *other;
+	int complete_rewrite = 0;
 
 	if (DIFF_PAIR_UNMERGED(p)) {
 		/* unmerged */
-		builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat);
+		builtin_diffstat(p->one->path, NULL, NULL, NULL, diffstat, 0);
 		return;
 	}
 
@@ -1009,7 +1175,9 @@ static void run_diffstat(struct diff_filepair *p, struct diff_options *o,
 	diff_fill_sha1_info(p->one);
 	diff_fill_sha1_info(p->two);
 
-	builtin_diffstat(name, other, p->one, p->two, diffstat);
+	if (p->status == DIFF_STATUS_MODIFIED && p->score)
+		complete_rewrite = 1;
+	builtin_diffstat(name, other, p->one, p->two, diffstat, complete_rewrite);
 }
 
 void diff_setup(struct diff_options *options)
@@ -1019,6 +1187,7 @@ void diff_setup(struct diff_options *options)
 	options->line_termination = '\n';
 	options->break_opt = -1;
 	options->rename_limit = -1;
+	options->context = 3;
 
 	options->change = diff_change;
 	options->add_remove = diff_addremove;
@@ -1036,8 +1205,7 @@ int diff_setup_done(struct diff_options *options)
 	 * recursive bits for other formats here.
 	 */
 	if ((options->output_format == DIFF_FORMAT_PATCH) ||
-	    (options->output_format == DIFF_FORMAT_DIFFSTAT) ||
-	    (options->with_stat))
+	    (options->output_format == DIFF_FORMAT_DIFFSTAT))
 		options->recursive = 1;
 
 	if (options->detect_rename && options->rename_limit < 0)
@@ -1060,17 +1228,68 @@ int diff_setup_done(struct diff_options *options)
 	return 0;
 }
 
+int opt_arg(const char *arg, int arg_short, const char *arg_long, int *val)
+{
+	char c, *eq;
+	int len;
+
+	if (*arg != '-')
+		return 0;
+	c = *++arg;
+	if (!c)
+		return 0;
+	if (c == arg_short) {
+		c = *++arg;
+		if (!c)
+			return 1;
+		if (val && isdigit(c)) {
+			char *end;
+			int n = strtoul(arg, &end, 10);
+			if (*end)
+				return 0;
+			*val = n;
+			return 1;
+		}
+		return 0;
+	}
+	if (c != '-')
+		return 0;
+	arg++;
+	eq = strchr(arg, '=');
+	if (eq)
+		len = eq - arg;
+	else
+		len = strlen(arg);
+	if (!len || strncmp(arg, arg_long, len))
+		return 0;
+	if (eq) {
+		int n;
+		char *end;
+		if (!isdigit(*++eq))
+			return 0;
+		n = strtoul(eq, &end, 10);
+		if (*end)
+			return 0;
+		*val = n;
+	}
+	return 1;
+}
+
 int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 {
 	const char *arg = av[0];
 	if (!strcmp(arg, "-p") || !strcmp(arg, "-u"))
 		options->output_format = DIFF_FORMAT_PATCH;
+	else if (opt_arg(arg, 'U', "unified", &options->context))
+		options->output_format = DIFF_FORMAT_PATCH;
 	else if (!strcmp(arg, "--patch-with-raw")) {
 		options->output_format = DIFF_FORMAT_PATCH;
 		options->with_raw = 1;
 	}
 	else if (!strcmp(arg, "--stat"))
 		options->output_format = DIFF_FORMAT_DIFFSTAT;
+	else if (!strcmp(arg, "--summary"))
+		options->summary = 1;
 	else if (!strcmp(arg, "--patch-with-stat")) {
 		options->output_format = DIFF_FORMAT_PATCH;
 		options->with_stat = 1;
@@ -1081,6 +1300,10 @@ int diff_opt_parse(struct diff_options *options, const char **av, int ac)
 		options->rename_limit = strtoul(arg+2, NULL, 10);
 	else if (!strcmp(arg, "--full-index"))
 		options->full_index = 1;
+	else if (!strcmp(arg, "--binary")) {
+		options->output_format = DIFF_FORMAT_PATCH;
+		options->full_index = options->binary = 1;
+	}
 	else if (!strcmp(arg, "--name-only"))
 		options->output_format = DIFF_FORMAT_NAME;
 	else if (!strcmp(arg, "--name-status"))
@@ -1375,7 +1598,7 @@ static void diff_flush_patch(struct diff_filepair *p, struct diff_options *o)
 }
 
 static void diff_flush_stat(struct diff_filepair *p, struct diff_options *o,
-		struct diffstat_t *diffstat)
+			    struct diffstat_t *diffstat)
 {
 	if (diff_unmodified_pair(p))
 		return;
@@ -1537,6 +1760,85 @@ static void flush_one_pair(struct diff_filepair *p,
 	}
 }
 
+static void show_file_mode_name(const char *newdelete, struct diff_filespec *fs)
+{
+	if (fs->mode)
+		printf(" %s mode %06o %s\n", newdelete, fs->mode, fs->path);
+	else
+		printf(" %s %s\n", newdelete, fs->path);
+}
+
+
+static void show_mode_change(struct diff_filepair *p, int show_name)
+{
+	if (p->one->mode && p->two->mode && p->one->mode != p->two->mode) {
+		if (show_name)
+			printf(" mode change %06o => %06o %s\n",
+			       p->one->mode, p->two->mode, p->two->path);
+		else
+			printf(" mode change %06o => %06o\n",
+			       p->one->mode, p->two->mode);
+	}
+}
+
+static void show_rename_copy(const char *renamecopy, struct diff_filepair *p)
+{
+	const char *old, *new;
+
+	/* Find common prefix */
+	old = p->one->path;
+	new = p->two->path;
+	while (1) {
+		const char *slash_old, *slash_new;
+		slash_old = strchr(old, '/');
+		slash_new = strchr(new, '/');
+		if (!slash_old ||
+		    !slash_new ||
+		    slash_old - old != slash_new - new ||
+		    memcmp(old, new, slash_new - new))
+			break;
+		old = slash_old + 1;
+		new = slash_new + 1;
+	}
+	/* p->one->path thru old is the common prefix, and old and new
+	 * through the end of names are renames
+	 */
+	if (old != p->one->path)
+		printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
+		       (int)(old - p->one->path), p->one->path,
+		       old, new, (int)(0.5 + p->score * 100.0/MAX_SCORE));
+	else
+		printf(" %s %s => %s (%d%%)\n", renamecopy,
+		       p->one->path, p->two->path,
+		       (int)(0.5 + p->score * 100.0/MAX_SCORE));
+	show_mode_change(p, 0);
+}
+
+static void diff_summary(struct diff_filepair *p)
+{
+	switch(p->status) {
+	case DIFF_STATUS_DELETED:
+		show_file_mode_name("delete", p->one);
+		break;
+	case DIFF_STATUS_ADDED:
+		show_file_mode_name("create", p->two);
+		break;
+	case DIFF_STATUS_COPIED:
+		show_rename_copy("copy", p);
+		break;
+	case DIFF_STATUS_RENAMED:
+		show_rename_copy("rename", p);
+		break;
+	default:
+		if (p->score) {
+			printf(" rewrite %s (%d%%)\n", p->two->path,
+				(int)(0.5 + p->score * 100.0/MAX_SCORE));
+			show_mode_change(p, 0);
+		} else	show_mode_change(p, 1);
+		break;
+	}
+}
+
 void diff_flush(struct diff_options *options)
 {
 	struct diff_queue_struct *q = &diff_queued_diff;
@@ -1560,7 +1862,7 @@ void diff_flush(struct diff_options *options)
 		for (i = 0; i < q->nr; i++) {
 			struct diff_filepair *p = q->queue[i];
 			flush_one_pair(p, DIFF_FORMAT_DIFFSTAT, options,
-					diffstat);
+				       diffstat);
 		}
 		show_stats(diffstat);
 		free(diffstat);
@@ -1570,7 +1872,6 @@ void diff_flush(struct diff_options *options)
 	for (i = 0; i < q->nr; i++) {
 		struct diff_filepair *p = q->queue[i];
 		flush_one_pair(p, diff_output_format, options, diffstat);
-		diff_free_filepair(p);
 	}
 
 	if (diffstat) {
@@ -1578,6 +1879,12 @@ void diff_flush(struct diff_options *options)
 		free(diffstat);
 	}
 
+	for (i = 0; i < q->nr; i++) {
+		if (options->summary)
+			diff_summary(q->queue[i]);
+		diff_free_filepair(q->queue[i]);
+	}
+
 	free(q->queue);
 	q->queue = NULL;
 	q->nr = q->alloc = 0;