Builtin git-apply.

Signed-off-by: Peter Eriksen <s022018@student.dtu.dk>
Signed-off-by: Junio C Hamano <junkio@cox.net>

1 files changed, 2300 insertions, 0 deletions

diff --git a/builtin-apply.c b/builtin-apply.c
new file mode 100644
index 000000000..4056b9d67
--- /dev/null
+++ b/builtin-apply.c
@@ -0,0 +1,2300 @@
+/*
+ * apply.c
+ *
+ * Copyright (C) Linus Torvalds, 2005
+ *
+ * This applies patches on top of some (arbitrary) version of the SCM.
+ *
+ */
+#include <fnmatch.h>
+#include "cache.h"
+#include "quote.h"
+#include "blob.h"
+#include "delta.h"
+#include "builtin.h"
+
+//  --check turns on checking that the working tree matches the
+//    files that are being modified, but doesn't apply the patch
+//  --stat does just a diffstat, and doesn't actually apply
+//  --numstat does numeric diffstat, and doesn't actually apply
+//  --index-info shows the old and new index info for paths if available.
+//  --index updates the cache as well.
+//  --cached updates only the cache without ever touching the working tree.
+//
+static const char *prefix;
+static int prefix_length = -1;
+static int newfd = -1;
+
+static int p_value = 1;
+static int allow_binary_replacement = 0;
+static int check_index = 0;
+static int write_index = 0;
+static int cached = 0;
+static int diffstat = 0;
+static int numstat = 0;
+static int summary = 0;
+static int check = 0;
+static int apply = 1;
+static int no_add = 0;
+static int show_index_info = 0;
+static int line_termination = '\n';
+static unsigned long p_context = -1;
+static const char apply_usage[] =
+"git-apply [--stat] [--numstat] [--summary] [--check] [--index] [--cached] [--apply] [--no-add] [--index-info] [--allow-binary-replacement] [-z] [-pNUM] [-CNUM] [--whitespace=<nowarn|warn|error|error-all|strip>] <patch>...";
+
+static enum whitespace_eol {
+	nowarn_whitespace,
+	warn_on_whitespace,
+	error_on_whitespace,
+	strip_whitespace,
+} new_whitespace = warn_on_whitespace;
+static int whitespace_error = 0;
+static int squelch_whitespace_errors = 5;
+static int applied_after_stripping = 0;
+static const char *patch_input_file = NULL;
+
+static void parse_whitespace_option(const char *option)
+{
+	if (!option) {
+		new_whitespace = warn_on_whitespace;
+		return;
+	}
+	if (!strcmp(option, "warn")) {
+		new_whitespace = warn_on_whitespace;
+		return;
+	}
+	if (!strcmp(option, "nowarn")) {
+		new_whitespace = nowarn_whitespace;
+		return;
+	}
+	if (!strcmp(option, "error")) {
+		new_whitespace = error_on_whitespace;
+		return;
+	}
+	if (!strcmp(option, "error-all")) {
+		new_whitespace = error_on_whitespace;
+		squelch_whitespace_errors = 0;
+		return;
+	}
+	if (!strcmp(option, "strip")) {
+		new_whitespace = strip_whitespace;
+		return;
+	}
+	die("unrecognized whitespace option '%s'", option);
+}
+
+static void set_default_whitespace_mode(const char *whitespace_option)
+{
+	if (!whitespace_option && !apply_default_whitespace) {
+		new_whitespace = (apply
+				  ? warn_on_whitespace
+				  : nowarn_whitespace);
+	}
+}
+
+/*
+ * For "diff-stat" like behaviour, we keep track of the biggest change
+ * we've seen, and the longest filename. That allows us to do simple
+ * scaling.
+ */
+static int max_change, max_len;
+
+/*
+ * Various "current state", notably line numbers and what
+ * file (and how) we're patching right now.. The "is_xxxx"
+ * things are flags, where -1 means "don't know yet".
+ */
+static int linenr = 1;
+
+struct fragment {
+	unsigned long leading, trailing;
+	unsigned long oldpos, oldlines;
+	unsigned long newpos, newlines;
+	const char *patch;
+	int size;
+	struct fragment *next;
+};
+
+struct patch {
+	char *new_name, *old_name, *def_name;
+	unsigned int old_mode, new_mode;
+	int is_rename, is_copy, is_new, is_delete, is_binary;
+#define BINARY_DELTA_DEFLATED 1
+#define BINARY_LITERAL_DEFLATED 2
+	unsigned long deflate_origlen;
+	int lines_added, lines_deleted;
+	int score;
+	struct fragment *fragments;
+	char *result;
+	unsigned long resultsize;
+	char old_sha1_prefix[41];
+	char new_sha1_prefix[41];
+	struct patch *next;
+};
+
+#define CHUNKSIZE (8192)
+#define SLOP (16)
+
+static void *read_patch_file(int fd, unsigned long *sizep)
+{
+	unsigned long size = 0, alloc = CHUNKSIZE;
+	void *buffer = xmalloc(alloc);
+
+	for (;;) {
+		int nr = alloc - size;
+		if (nr < 1024) {
+			alloc += CHUNKSIZE;
+			buffer = xrealloc(buffer, alloc);
+			nr = alloc - size;
+		}
+		nr = xread(fd, buffer + size, nr);
+		if (!nr)
+			break;
+		if (nr < 0)
+			die("git-apply: read returned %s", strerror(errno));
+		size += nr;
+	}
+	*sizep = size;
+
+	/*
+	 * Make sure that we have some slop in the buffer
+	 * so that we can do speculative "memcmp" etc, and
+	 * see to it that it is NUL-filled.
+	 */
+	if (alloc < size + SLOP)
+		buffer = xrealloc(buffer, size + SLOP);
+	memset(buffer + size, 0, SLOP);
+	return buffer;
+}
+
+static unsigned long linelen(const char *buffer, unsigned long size)
+{
+	unsigned long len = 0;
+	while (size--) {
+		len++;
+		if (*buffer++ == '\n')
+			break;
+	}
+	return len;
+}
+
+static int is_dev_null(const char *str)
+{
+	return !memcmp("/dev/null", str, 9) && isspace(str[9]);
+}
+
+#define TERM_SPACE	1
+#define TERM_TAB	2
+
+static int name_terminate(const char *name, int namelen, int c, int terminate)
+{
+	if (c == ' ' && !(terminate & TERM_SPACE))
+		return 0;
+	if (c == '\t' && !(terminate & TERM_TAB))
+		return 0;
+
+	return 1;
+}
+
+static char * find_name(const char *line, char *def, int p_value, int terminate)
+{
+	int len;
+	const char *start = line;
+	char *name;
+
+	if (*line == '"') {
+		/* Proposed "new-style" GNU patch/diff format; see
+		 * http://marc.theaimsgroup.com/?l=git&m=112927316408690&w=2
+		 */
+		name = unquote_c_style(line, NULL);
+		if (name) {
+			char *cp = name;
+			while (p_value) {
+				cp = strchr(name, '/');
+				if (!cp)
+					break;
+				cp++;
+				p_value--;
+			}
+			if (cp) {
+				/* name can later be freed, so we need
+				 * to memmove, not just return cp
+				 */
+				memmove(name, cp, strlen(cp) + 1);
+				free(def);
+				return name;
+			}
+			else {
+				free(name);
+				name = NULL;
+			}
+		}
+	}
+
+	for (;;) {
+		char c = *line;
+
+		if (isspace(c)) {
+			if (c == '\n')
+				break;
+			if (name_terminate(start, line-start, c, terminate))
+				break;
+		}
+		line++;
+		if (c == '/' && !--p_value)
+			start = line;
+	}
+	if (!start)
+		return def;
+	len = line - start;
+	if (!len)
+		return def;
+
+	/*
+	 * Generally we prefer the shorter name, especially
+	 * if the other one is just a variation of that with
+	 * something else tacked on to the end (ie "file.orig"
+	 * or "file~").
+	 */
+	if (def) {
+		int deflen = strlen(def);
+		if (deflen < len && !strncmp(start, def, deflen))
+			return def;
+	}
+
+	name = xmalloc(len + 1);
+	memcpy(name, start, len);
+	name[len] = 0;
+	free(def);
+	return name;
+}
+
+/*
+ * Get the name etc info from the --/+++ lines of a traditional patch header
+ *
+ * NOTE! This hardcodes "-p1" behaviour in filename detection.
+ *
+ * FIXME! The end-of-filename heuristics are kind of screwy. For existing
+ * files, we can happily check the index for a match, but for creating a
+ * new file we should try to match whatever "patch" does. I have no idea.
+ */
+static void parse_traditional_patch(const char *first, const char *second, struct patch *patch)
+{
+	char *name;
+
+	first += 4;	// skip "--- "
+	second += 4;	// skip "+++ "
+	if (is_dev_null(first)) {
+		patch->is_new = 1;
+		patch->is_delete = 0;
+		name = find_name(second, NULL, p_value, TERM_SPACE | TERM_TAB);
+		patch->new_name = name;
+	} else if (is_dev_null(second)) {
+		patch->is_new = 0;
+		patch->is_delete = 1;
+		name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
+		patch->old_name = name;
+	} else {
+		name = find_name(first, NULL, p_value, TERM_SPACE | TERM_TAB);
+		name = find_name(second, name, p_value, TERM_SPACE | TERM_TAB);
+		patch->old_name = patch->new_name = name;
+	}
+	if (!name)
+		die("unable to find filename in patch at line %d", linenr);
+}
+
+static int gitdiff_hdrend(const char *line, struct patch *patch)
+{
+	return -1;
+}
+
+/*
+ * We're anal about diff header consistency, to make
+ * sure that we don't end up having strange ambiguous
+ * patches floating around.
+ *
+ * As a result, gitdiff_{old|new}name() will check
+ * their names against any previous information, just
+ * to make sure..
+ */
+static char *gitdiff_verify_name(const char *line, int isnull, char *orig_name, const char *oldnew)
+{
+	if (!orig_name && !isnull)
+		return find_name(line, NULL, 1, 0);
+
+	if (orig_name) {
+		int len;
+		const char *name;
+		char *another;
+		name = orig_name;
+		len = strlen(name);
+		if (isnull)
+			die("git-apply: bad git-diff - expected /dev/null, got %s on line %d", name, linenr);
+		another = find_name(line, NULL, 1, 0);
+		if (!another || memcmp(another, name, len))
+			die("git-apply: bad git-diff - inconsistent %s filename on line %d", oldnew, linenr);
+		free(another);
+		return orig_name;
+	}
+	else {
+		/* expect "/dev/null" */
+		if (memcmp("/dev/null", line, 9) || line[9] != '\n')
+			die("git-apply: bad git-diff - expected /dev/null on line %d", linenr);
+		return NULL;
+	}
+}
+
+static int gitdiff_oldname(const char *line, struct patch *patch)
+{
+	patch->old_name = gitdiff_verify_name(line, patch->is_new, patch->old_name, "old");
+	return 0;
+}
+
+static int gitdiff_newname(const char *line, struct patch *patch)
+{
+	patch->new_name = gitdiff_verify_name(line, patch->is_delete, patch->new_name, "new");
+	return 0;
+}
+
+static int gitdiff_oldmode(const char *line, struct patch *patch)
+{
+	patch->old_mode = strtoul(line, NULL, 8);
+	return 0;
+}
+
+static int gitdiff_newmode(const char *line, struct patch *patch)
+{
+	patch->new_mode = strtoul(line, NULL, 8);
+	return 0;
+}
+
+static int gitdiff_delete(const char *line, struct patch *patch)
+{
+	patch->is_delete = 1;
+	patch->old_name = patch->def_name;
+	return gitdiff_oldmode(line, patch);
+}
+
+static int gitdiff_newfile(const char *line, struct patch *patch)
+{
+	patch->is_new = 1;
+	patch->new_name = patch->def_name;
+	return gitdiff_newmode(line, patch);
+}
+
+static int gitdiff_copysrc(const char *line, struct patch *patch)
+{
+	patch->is_copy = 1;
+	patch->old_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_copydst(const char *line, struct patch *patch)
+{
+	patch->is_copy = 1;
+	patch->new_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_renamesrc(const char *line, struct patch *patch)
+{
+	patch->is_rename = 1;
+	patch->old_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_renamedst(const char *line, struct patch *patch)
+{
+	patch->is_rename = 1;
+	patch->new_name = find_name(line, NULL, 0, 0);
+	return 0;
+}
+
+static int gitdiff_similarity(const char *line, struct patch *patch)
+{
+	if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
+		patch->score = 0;
+	return 0;
+}
+
+static int gitdiff_dissimilarity(const char *line, struct patch *patch)
+{
+	if ((patch->score = strtoul(line, NULL, 10)) == ULONG_MAX)
+		patch->score = 0;
+	return 0;
+}
+
+static int gitdiff_index(const char *line, struct patch *patch)
+{
+	/* index line is N hexadecimal, "..", N hexadecimal,
+	 * and optional space with octal mode.
+	 */
+	const char *ptr, *eol;
+	int len;
+
+	ptr = strchr(line, '.');
+	if (!ptr || ptr[1] != '.' || 40 < ptr - line)
+		return 0;
+	len = ptr - line;
+	memcpy(patch->old_sha1_prefix, line, len);
+	patch->old_sha1_prefix[len] = 0;
+
+	line = ptr + 2;
+	ptr = strchr(line, ' ');
+	eol = strchr(line, '\n');
+
+	if (!ptr || eol < ptr)
+		ptr = eol;
+	len = ptr - line;
+
+	if (40 < len)
+		return 0;
+	memcpy(patch->new_sha1_prefix, line, len);
+	patch->new_sha1_prefix[len] = 0;
+	if (*ptr == ' ')
+		patch->new_mode = patch->old_mode = strtoul(ptr+1, NULL, 8);
+	return 0;
+}
+
+/*
+ * This is normal for a diff that doesn't change anything: we'll fall through
+ * into the next diff. Tell the parser to break out.
+ */
+static int gitdiff_unrecognized(const char *line, struct patch *patch)
+{
+	return -1;
+}
+
+static const char *stop_at_slash(const char *line, int llen)
+{
+	int i;
+
+	for (i = 0; i < llen; i++) {
+		int ch = line[i];
+		if (ch == '/')
+			return line + i;
+	}
+	return NULL;
+}
+
+/* This is to extract the same name that appears on "diff --git"
+ * line.  We do not find and return anything if it is a rename
+ * patch, and it is OK because we will find the name elsewhere.
+ * We need to reliably find name only when it is mode-change only,
+ * creation or deletion of an empty file.  In any of these cases,
+ * both sides are the same name under a/ and b/ respectively.
+ */
+static char *git_header_name(char *line, int llen)
+{
+	int len;
+	const char *name;
+	const char *second = NULL;
+
+	line += strlen("diff --git ");
+	llen -= strlen("diff --git ");
+
+	if (*line == '"') {
+		const char *cp;
+		char *first = unquote_c_style(line, &second);
+		if (!first)
+			return NULL;
+
+		/* advance to the first slash */
+		cp = stop_at_slash(first, strlen(first));
+		if (!cp || cp == first) {
+			/* we do not accept absolute paths */
+		free_first_and_fail:
+			free(first);
+			return NULL;
+		}
+		len = strlen(cp+1);
+		memmove(first, cp+1, len+1); /* including NUL */
+
+		/* second points at one past closing dq of name.
+		 * find the second name.
+		 */
+		while ((second < line + llen) && isspace(*second))
+			second++;
+
+		if (line + llen <= second)
+			goto free_first_and_fail;
+		if (*second == '"') {
+			char *sp = unquote_c_style(second, NULL);
+			if (!sp)
+				goto free_first_and_fail;
+			cp = stop_at_slash(sp, strlen(sp));
+			if (!cp || cp == sp) {
+			free_both_and_fail:
+				free(sp);
+				goto free_first_and_fail;
+			}
+			/* They must match, otherwise ignore */
+			if (strcmp(cp+1, first))
+				goto free_both_and_fail;
+			free(sp);
+			return first;
+		}
+
+		/* unquoted second */
+		cp = stop_at_slash(second, line + llen - second);
+		if (!cp || cp == second)
+			goto free_first_and_fail;
+		cp++;
+		if (line + llen - cp != len + 1 ||
+		    memcmp(first, cp, len))
+			goto free_first_and_fail;
+		return first;
+	}
+
+	/* unquoted first name */
+	name = stop_at_slash(line, llen);
+	if (!name || name == line)
+		return NULL;
+
+	name++;
+
+	/* since the first name is unquoted, a dq if exists must be
+	 * the beginning of the second name.
+	 */
+	for (second = name; second < line + llen; second++) {
+		if (*second == '"') {
+			const char *cp = second;
+			const char *np;
+			char *sp = unquote_c_style(second, NULL);
+
+			if (!sp)
+				return NULL;
+			np = stop_at_slash(sp, strlen(sp));
+			if (!np || np == sp) {
+			free_second_and_fail:
+				free(sp);
+				return NULL;
+			}
+			np++;
+			len = strlen(np);
+			if (len < cp - name &&
+			    !strncmp(np, name, len) &&
+			    isspace(name[len])) {
+				/* Good */
+				memmove(sp, np, len + 1);
+				return sp;
+			}
+			goto free_second_and_fail;
+		}
+	}
+
+	/*
+	 * Accept a name only if it shows up twice, exactly the same
+	 * form.
+	 */
+	for (len = 0 ; ; len++) {
+		char c = name[len];
+
+		switch (c) {
+		default:
+			continue;
+		case '\n':
+			return NULL;
+		case '\t': case ' ':
+			second = name+len;
+			for (;;) {
+				char c = *second++;
+				if (c == '\n')
+					return NULL;
+				if (c == '/')
+					break;
+			}
+			if (second[len] == '\n' && !memcmp(name, second, len)) {
+				char *ret = xmalloc(len + 1);
+				memcpy(ret, name, len);
+				ret[len] = 0;
+				return ret;
+			}
+		}
+	}
+	return NULL;
+}
+
+/* Verify that we recognize the lines following a git header */
+static int parse_git_header(char *line, int len, unsigned int size, struct patch *patch)
+{
+	unsigned long offset;
+
+	/* A git diff has explicit new/delete information, so we don't guess */
+	patch->is_new = 0;
+	patch->is_delete = 0;
+
+	/*
+	 * Some things may not have the old name in the
+	 * rest of the headers anywhere (pure mode changes,
+	 * or removing or adding empty files), so we get
+	 * the default name from the header.
+	 */
+	patch->def_name = git_header_name(line, len);
+
+	line += len;
+	size -= len;
+	linenr++;
+	for (offset = len ; size > 0 ; offset += len, size -= len, line += len, linenr++) {
+		static const struct opentry {
+			const char *str;
+			int (*fn)(const char *, struct patch *);
+		} optable[] = {
+			{ "@@ -", gitdiff_hdrend },
+			{ "--- ", gitdiff_oldname },
+			{ "+++ ", gitdiff_newname },
+			{ "old mode ", gitdiff_oldmode },
+			{ "new mode ", gitdiff_newmode },
+			{ "deleted file mode ", gitdiff_delete },
+			{ "new file mode ", gitdiff_newfile },
+			{ "copy from ", gitdiff_copysrc },
+			{ "copy to ", gitdiff_copydst },
+			{ "rename old ", gitdiff_renamesrc },
+			{ "rename new ", gitdiff_renamedst },
+			{ "rename from ", gitdiff_renamesrc },
+			{ "rename to ", gitdiff_renamedst },
+			{ "similarity index ", gitdiff_similarity },
+			{ "dissimilarity index ", gitdiff_dissimilarity },
+			{ "index ", gitdiff_index },
+			{ "", gitdiff_unrecognized },
+		};
+		int i;
+
+		len = linelen(line, size);
+		if (!len || line[len-1] != '\n')
+			break;
+		for (i = 0; i < ARRAY_SIZE(optable); i++) {
+			const struct opentry *p = optable + i;
+			int oplen = strlen(p->str);
+			if (len < oplen || memcmp(p->str, line, oplen))
+				continue;
+			if (p->fn(line + oplen, patch) < 0)
+				return offset;
+			break;
+		}
+	}
+
+	return offset;
+}
+
+static int parse_num(const char *line, unsigned long *p)
+{
+	char *ptr;
+
+	if (!isdigit(*line))
+		return 0;
+	*p = strtoul(line, &ptr, 10);
+	return ptr - line;
+}
+
+static int parse_range(const char *line, int len, int offset, const char *expect,
+			unsigned long *p1, unsigned long *p2)
+{
+	int digits, ex;
+
+	if (offset < 0 || offset >= len)
+		return -1;
+	line += offset;
+	len -= offset;
+
+	digits = parse_num(line, p1);
+	if (!digits)
+		return -1;
+
+	offset += digits;
+	line += digits;
+	len -= digits;
+
+	*p2 = 1;
+	if (*line == ',') {
+		digits = parse_num(line+1, p2);
+		if (!digits)
+			return -1;
+
+		offset += digits+1;
+		line += digits+1;
+		len -= digits+1;
+	}
+
+	ex = strlen(expect);
+	if (ex > len)
+		return -1;
+	if (memcmp(line, expect, ex))
+		return -1;
+
+	return offset + ex;
+}
+
+/*
+ * Parse a unified diff fragment header of the
+ * form "@@ -a,b +c,d @@"
+ */
+static int parse_fragment_header(char *line, int len, struct fragment *fragment)
+{
+	int offset;
+
+	if (!len || line[len-1] != '\n')
+		return -1;
+
+	/* Figure out the number of lines in a fragment */
+	offset = parse_range(line, len, 4, " +", &fragment->oldpos, &fragment->oldlines);
+	offset = parse_range(line, len, offset, " @@", &fragment->newpos, &fragment->newlines);
+
+	return offset;
+}
+
+static int find_header(char *line, unsigned long size, int *hdrsize, struct patch *patch)
+{
+	unsigned long offset, len;
+
+	patch->is_rename = patch->is_copy = 0;
+	patch->is_new = patch->is_delete = -1;
+	patch->old_mode = patch->new_mode = 0;
+	patch->old_name = patch->new_name = NULL;
+	for (offset = 0; size > 0; offset += len, size -= len, line += len, linenr++) {
+		unsigned long nextlen;
+
+		len = linelen(line, size);
+		if (!len)
+			break;
+
+		/* Testing this early allows us to take a few shortcuts.. */
+		if (len < 6)
+			continue;
+
+		/*
+		 * Make sure we don't find any unconnected patch fragmants.
+		 * That's a sign that we didn't find a header, and that a
+		 * patch has become corrupted/broken up.
+		 */
+		if (!memcmp("@@ -", line, 4)) {
+			struct fragment dummy;
+			if (parse_fragment_header(line, len, &dummy) < 0)
+				continue;
+			error("patch fragment without header at line %d: %.*s", linenr, (int)len-1, line);
+		}
+
+		if (size < len + 6)
+			break;
+
+		/*
+		 * Git patch? It might not have a real patch, just a rename
+		 * or mode change, so we handle that specially
+		 */
+		if (!memcmp("diff --git ", line, 11)) {
+			int git_hdr_len = parse_git_header(line, len, size, patch);
+			if (git_hdr_len <= len)
+				continue;
+			if (!patch->old_name && !patch->new_name) {
+				if (!patch->def_name)
+					die("git diff header lacks filename information (line %d)", linenr);
+				patch->old_name = patch->new_name = patch->def_name;
+			}
+			*hdrsize = git_hdr_len;
+			return offset;
+		}
+
+		/** --- followed by +++ ? */
+		if (memcmp("--- ", line,  4) || memcmp("+++ ", line + len, 4))
+			continue;
+
+		/*
+		 * We only accept unified patches, so we want it to
+		 * at least have "@@ -a,b +c,d @@\n", which is 14 chars
+		 * minimum
+		 */
+		nextlen = linelen(line + len, size - len);
+		if (size < nextlen + 14 || memcmp("@@ -", line + len + nextlen, 4))
+			continue;
+
+		/* Ok, we'll consider it a patch */
+		parse_traditional_patch(line, line+len, patch);
+		*hdrsize = len + nextlen;
+		linenr += 2;
+		return offset;
+	}
+	return -1;
+}
+
+/*
+ * Parse a unified diff. Note that this really needs
+ * to parse each fragment separately, since the only
+ * way to know the difference between a "---" that is
+ * part of a patch, and a "---" that starts the next
+ * patch is to look at the line counts..
+ */
+static int parse_fragment(char *line, unsigned long size, struct patch *patch, struct fragment *fragment)
+{
+	int added, deleted;
+	int len = linelen(line, size), offset;
+	unsigned long oldlines, newlines;
+	unsigned long leading, trailing;
+
+	offset = parse_fragment_header(line, len, fragment);
+	if (offset < 0)
+		return -1;
+	oldlines = fragment->oldlines;
+	newlines = fragment->newlines;
+	leading = 0;
+	trailing = 0;
+
+	if (patch->is_new < 0) {
+		patch->is_new =  !oldlines;
+		if (!oldlines)
+			patch->old_name = NULL;
+	}
+	if (patch->is_delete < 0) {
+		patch->is_delete = !newlines;
+		if (!newlines)
+			patch->new_name = NULL;
+	}
+
+	if (patch->is_new && oldlines)
+		return error("new file depends on old contents");
+	if (patch->is_delete != !newlines) {
+		if (newlines)
+			return error("deleted file still has contents");
+		fprintf(stderr, "** warning: file %s becomes empty but is not deleted\n", patch->new_name);
+	}
+
+	/* Parse the thing.. */
+	line += len;
+	size -= len;
+	linenr++;
+	added = deleted = 0;
+	for (offset = len; size > 0; offset += len, size -= len, line += len, linenr++) {
+		if (!oldlines && !newlines)
+			break;
+		len = linelen(line, size);
+		if (!len || line[len-1] != '\n')
+			return -1;
+		switch (*line) {
+		default:
+			return -1;
+		case ' ':
+			oldlines--;
+			newlines--;
+			if (!deleted && !added)
+				leading++;
+			trailing++;
+			break;
+		case '-':
+			deleted++;
+			oldlines--;
+			trailing = 0;
+			break;
+		case '+':
+			/*
+			 * We know len is at least two, since we have a '+' and
+			 * we checked that the last character was a '\n' above.
+			 * That is, an addition of an empty line would check
+			 * the '+' here.  Sneaky...
+			 */
+			if ((new_whitespace != nowarn_whitespace) &&
+			    isspace(line[len-2])) {
+				whitespace_error++;
+				if (squelch_whitespace_errors &&
+				    squelch_whitespace_errors <
+				    whitespace_error)
+					;
+				else {
+					fprintf(stderr, "Adds trailing whitespace.\n%s:%d:%.*s\n",
+						patch_input_file,
+						linenr, len-2, line+1);
+				}
+			}
+			added++;
+			newlines--;
+			trailing = 0;
+			break;
+
+                /* We allow "\ No newline at end of file". Depending
+                 * on locale settings when the patch was produced we
+                 * don't know what this line looks like. The only
+                 * thing we do know is that it begins with "\ ".
+		 * Checking for 12 is just for sanity check -- any
+		 * l10n of "\ No newline..." is at least that long.
+		 */
+		case '\\':
+			if (len < 12 || memcmp(line, "\\ ", 2))
+				return -1;
+			break;
+		}
+	}
+	if (oldlines || newlines)
+		return -1;
+	fragment->leading = leading;
+	fragment->trailing = trailing;
+
+	/* If a fragment ends with an incomplete line, we failed to include
+	 * it in the above loop because we hit oldlines == newlines == 0
+	 * before seeing it.
+	 */
+	if (12 < size && !memcmp(line, "\\ ", 2))
+		offset += linelen(line, size);
+
+	patch->lines_added += added;
+	patch->lines_deleted += deleted;
+	return offset;
+}
+
+static int parse_single_patch(char *line, unsigned long size, struct patch *patch)
+{
+	unsigned long offset = 0;
+	struct fragment **fragp = &patch->fragments;
+
+	while (size > 4 && !memcmp(line, "@@ -", 4)) {
+		struct fragment *fragment;
+		int len;
+
+		fragment = xcalloc(1, sizeof(*fragment));
+		len = parse_fragment(line, size, patch, fragment);
+		if (len <= 0)
+			die("corrupt patch at line %d", linenr);
+
+		fragment->patch = line;
+		fragment->size = len;
+
+		*fragp = fragment;
+		fragp = &fragment->next;
+
+		offset += len;
+		line += len;
+		size -= len;
+	}
+	return offset;
+}
+
+static inline int metadata_changes(struct patch *patch)
+{
+	return	patch->is_rename > 0 ||
+		patch->is_copy > 0 ||
+		patch->is_new > 0 ||
+		patch->is_delete ||
+		(patch->old_mode && patch->new_mode &&
+		 patch->old_mode != patch->new_mode);
+}
+
+static int parse_binary(char *buffer, unsigned long size, struct patch *patch)
+{
+	/* We have read "GIT binary patch\n"; what follows is a line
+	 * that says the patch method (currently, either "deflated
+	 * literal" or "deflated delta") and the length of data before
+	 * deflating; a sequence of 'length-byte' followed by base-85
+	 * encoded data follows.
+	 *
+	 * Each 5-byte sequence of base-85 encodes up to 4 bytes,
+	 * and we would limit the patch line to 66 characters,
+	 * so one line can fit up to 13 groups that would decode
+	 * to 52 bytes max.  The length byte 'A'-'Z' corresponds
+	 * to 1-26 bytes, and 'a'-'z' corresponds to 27-52 bytes.
+	 * The end of binary is signalled with an empty line.
+	 */
+	int llen, used;
+	struct fragment *fragment;
+	char *data = NULL;
+
+	patch->fragments = fragment = xcalloc(1, sizeof(*fragment));
+
+	/* Grab the type of patch */
+	llen = linelen(buffer, size);
+	used = llen;
+	linenr++;
+
+	if (!strncmp(buffer, "delta ", 6)) {
+		patch->is_binary = BINARY_DELTA_DEFLATED;
+		patch->deflate_origlen = strtoul(buffer + 6, NULL, 10);
+	}
+	else if (!strncmp(buffer, "literal ", 8)) {
+		patch->is_binary = BINARY_LITERAL_DEFLATED;
+		patch->deflate_origlen = strtoul(buffer + 8, NULL, 10);
+	}
+	else
+		return error("unrecognized binary patch at line %d: %.*s",
+			     linenr-1, llen-1, buffer);
+	buffer += llen;
+	while (1) {
+		int byte_length, max_byte_length, newsize;
+		llen = linelen(buffer, size);
+		used += llen;
+		linenr++;
+		if (llen == 1)
+			break;
+		/* Minimum line is "A00000\n" which is 7-byte long,
+		 * and the line length must be multiple of 5 plus 2.
+		 */
+		if ((llen < 7) || (llen-2) % 5)
+			goto corrupt;
+		max_byte_length = (llen - 2) / 5 * 4;
+		byte_length = *buffer;
+		if ('A' <= byte_length && byte_length <= 'Z')
+			byte_length = byte_length - 'A' + 1;
+		else if ('a' <= byte_length && byte_length <= 'z')
+			byte_length = byte_length - 'a' + 27;
+		else
+			goto corrupt;
+		/* if the input length was not multiple of 4, we would
+		 * have filler at the end but the filler should never
+		 * exceed 3 bytes
+		 */
+		if (max_byte_length < byte_length ||
+		    byte_length <= max_byte_length - 4)
+			goto corrupt;
+		newsize = fragment->size + byte_length;
+		data = xrealloc(data, newsize);
+		if (decode_85(data + fragment->size,
+			      buffer + 1,
+			      byte_length))
+			goto corrupt;
+		fragment->size = newsize;
+		buffer += llen;
+		size -= llen;
+	}
+	fragment->patch = data;
+	return used;
+ corrupt:
+	return error("corrupt binary patch at line %d: %.*s",
+		     linenr-1, llen-1, buffer);
+}
+
+static int parse_chunk(char *buffer, unsigned long size, struct patch *patch)
+{
+	int hdrsize, patchsize;
+	int offset = find_header(buffer, size, &hdrsize, patch);
+
+	if (offset < 0)
+		return offset;
+
+	patchsize = parse_single_patch(buffer + offset + hdrsize, size - offset - hdrsize, patch);
+
+	if (!patchsize) {
+		static const char *binhdr[] = {
+			"Binary files ",
+			"Files ",
+			NULL,
+		};
+		static const char git_binary[] = "GIT binary patch\n";
+		int i;
+		int hd = hdrsize + offset;
+		unsigned long llen = linelen(buffer + hd, size - hd);
+
+		if (llen == sizeof(git_binary) - 1 &&
+		    !memcmp(git_binary, buffer + hd, llen)) {
+			int used;
+			linenr++;
+			used = parse_binary(buffer + hd + llen,
+					    size - hd - llen, patch);
+			if (used)
+				patchsize = used + llen;
+			else
+				patchsize = 0;
+		}
+		else if (!memcmp(" differ\n", buffer + hd + llen - 8, 8)) {
+			for (i = 0; binhdr[i]; i++) {
+				int len = strlen(binhdr[i]);
+				if (len < size - hd &&
+				    !memcmp(binhdr[i], buffer + hd, len)) {
+					linenr++;
+					patch->is_binary = 1;
+					patchsize = llen;
+					break;
+				}
+			}
+		}
+
+		/* Empty patch cannot be applied if:
+		 * - it is a binary patch and we do not do binary_replace, or
+		 * - text patch without metadata change
+		 */
+		if ((apply || check) &&
+		    (patch->is_binary
+		     ? !allow_binary_replacement
+		     : !metadata_changes(patch)))
+			die("patch with only garbage at line %d", linenr);
+	}
+
+	return offset + hdrsize + patchsize;
+}
+
+static const char pluses[] = "++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++";
+static const char minuses[]= "----------------------------------------------------------------------";
+
+static void show_stats(struct patch *patch)
+{
+	const char *prefix = "";
+	char *name = patch->new_name;
+	char *qname = NULL;
+	int len, max, add, del, total;
+
+	if (!name)
+		name = patch->old_name;
+
+	if (0 < (len = quote_c_style(name, NULL, NULL, 0))) {
+		qname = xmalloc(len + 1);
+		quote_c_style(name, qname, NULL, 0);
+		name = qname;
+	}
+
+	/*
+	 * "scale" the filename
+	 */
+	len = strlen(name);
+	max = max_len;
+	if (max > 50)
+		max = 50;
+	if (len > max) {
+		char *slash;
+		prefix = "...";
+		max -= 3;
+		name += len - max;
+		slash = strchr(name, '/');
+		if (slash)
+			name = slash;
+	}
+	len = max;
+
+	/*
+	 * scale the add/delete
+	 */
+	max = max_change;
+	if (max + len > 70)
+		max = 70 - len;
+
+	add = patch->lines_added;
+	del = patch->lines_deleted;
+	total = add + del;
+
+	if (max_change > 0) {
+		total = (total * max + max_change / 2) / max_change;
+		add = (add * max + max_change / 2) / max_change;
+		del = total - add;
+	}
+	if (patch->is_binary)
+		printf(" %s%-*s |  Bin\n", prefix, len, name);
+	else
+		printf(" %s%-*s |%5d %.*s%.*s\n", prefix,
+		       len, name, patch->lines_added + patch->lines_deleted,
+		       add, pluses, del, minuses);
+	if (qname)
+		free(qname);
+}
+
+static int read_old_data(struct stat *st, const char *path, void *buf, unsigned long size)
+{
+	int fd;
+	unsigned long got;
+
+	switch (st->st_mode & S_IFMT) {
+	case S_IFLNK:
+		return readlink(path, buf, size);
+	case S_IFREG:
+		fd = open(path, O_RDONLY);
+		if (fd < 0)
+			return error("unable to open %s", path);
+		got = 0;
+		for (;;) {
+			int ret = xread(fd, buf + got, size - got);
+			if (ret <= 0)
+				break;
+			got += ret;
+		}
+		close(fd);
+		return got;
+
+	default:
+		return -1;
+	}
+}
+
+static int find_offset(const char *buf, unsigned long size, const char *fragment, unsigned long fragsize, int line, int *lines)
+{
+	int i;
+	unsigned long start, backwards, forwards;
+
+	if (fragsize > size)
+		return -1;
+
+	start = 0;
+	if (line > 1) {
+		unsigned long offset = 0;
+		i = line-1;
+		while (offset + fragsize <= size) {
+			if (buf[offset++] == '\n') {
+				start = offset;
+				if (!--i)
+					break;
+			}
+		}
+	}
+
+	/* Exact line number? */
+	if (!memcmp(buf + start, fragment, fragsize))
+		return start;
+
+	/*
+	 * There's probably some smart way to do this, but I'll leave
+	 * that to the smart and beautiful people. I'm simple and stupid.
+	 */
+	backwards = start;
+	forwards = start;
+	for (i = 0; ; i++) {
+		unsigned long try;
+		int n;
+
+		/* "backward" */
+		if (i & 1) {
+			if (!backwards) {
+				if (forwards + fragsize > size)
+					break;
+				continue;
+			}
+			do {
+				--backwards;
+			} while (backwards && buf[backwards-1] != '\n');
+			try = backwards;
+		} else {
+			while (forwards + fragsize <= size) {
+				if (buf[forwards++] == '\n')
+					break;
+			}
+			try = forwards;
+		}
+
+		if (try + fragsize > size)
+			continue;
+		if (memcmp(buf + try, fragment, fragsize))
+			continue;
+		n = (i >> 1)+1;
+		if (i & 1)
+			n = -n;
+		*lines = n;
+		return try;
+	}
+
+	/*
+	 * We should start searching forward and backward.
+	 */
+	return -1;
+}
+
+static void remove_first_line(const char **rbuf, int *rsize)
+{
+	const char *buf = *rbuf;
+	int size = *rsize;
+	unsigned long offset;
+	offset = 0;
+	while (offset <= size) {
+		if (buf[offset++] == '\n')
+			break;
+	}
+	*rsize = size - offset;
+	*rbuf = buf + offset;
+}
+
+static void remove_last_line(const char **rbuf, int *rsize)
+{
+	const char *buf = *rbuf;
+	int size = *rsize;
+	unsigned long offset;
+	offset = size - 1;
+	while (offset > 0) {
+		if (buf[--offset] == '\n')
+			break;
+	}
+	*rsize = offset + 1;
+}
+
+struct buffer_desc {
+	char *buffer;
+	unsigned long size;
+	unsigned long alloc;
+};
+
+static int apply_line(char *output, const char *patch, int plen)
+{
+	/* plen is number of bytes to be copied from patch,
+	 * starting at patch+1 (patch[0] is '+').  Typically
+	 * patch[plen] is '\n'.
+	 */
+	int add_nl_to_tail = 0;
+	if ((new_whitespace == strip_whitespace) &&
+	    1 < plen && isspace(patch[plen-1])) {
+		if (patch[plen] == '\n')
+			add_nl_to_tail = 1;
+		plen--;
+		while (0 < plen && isspace(patch[plen]))
+			plen--;
+		applied_after_stripping++;
+	}
+	memcpy(output, patch + 1, plen);
+	if (add_nl_to_tail)
+		output[plen++] = '\n';
+	return plen;
+}
+
+static int apply_one_fragment(struct buffer_desc *desc, struct fragment *frag)
+{
+	char *buf = desc->buffer;
+	const char *patch = frag->patch;
+	int offset, size = frag->size;
+	char *old = xmalloc(size);
+	char *new = xmalloc(size);
+	const char *oldlines, *newlines;
+	int oldsize = 0, newsize = 0;
+	unsigned long leading, trailing;
+	int pos, lines;
+
+	while (size > 0) {
+		int len = linelen(patch, size);
+		int plen;
+
+		if (!len)
+			break;
+
+		/*
+		 * "plen" is how much of the line we should use for
+		 * the actual patch data. Normally we just remove the
+		 * first character on the line, but if the line is
+		 * followed by "\ No newline", then we also remove the
+		 * last one (which is the newline, of course).
+		 */
+		plen = len-1;
+		if (len < size && patch[len] == '\\')
+			plen--;
+		switch (*patch) {
+		case ' ':
+		case '-':
+			memcpy(old + oldsize, patch + 1, plen);
+			oldsize += plen;
+			if (*patch == '-')
+				break;
+		/* Fall-through for ' ' */
+		case '+':
+			if (*patch != '+' || !no_add)
+				newsize += apply_line(new + newsize, patch,
+						      plen);
+			break;
+		case '@': case '\\':
+			/* Ignore it, we already handled it */
+			break;
+		default:
+			return -1;
+		}
+		patch += len;
+		size -= len;
+	}
+
+#ifdef NO_ACCURATE_DIFF
+	if (oldsize > 0 && old[oldsize - 1] == '\n' &&
+			newsize > 0 && new[newsize - 1] == '\n') {
+		oldsize--;
+		newsize--;
+	}
+#endif
+
+	oldlines = old;
+	newlines = new;
+	leading = frag->leading;
+	trailing = frag->trailing;
+	lines = 0;
+	pos = frag->newpos;
+	for (;;) {
+		offset = find_offset(buf, desc->size, oldlines, oldsize, pos, &lines);
+		if (offset >= 0) {
+			int diff = newsize - oldsize;
+			unsigned long size = desc->size + diff;
+			unsigned long alloc = desc->alloc;
+
+			/* Warn if it was necessary to reduce the number
+			 * of context lines.
+			 */
+			if ((leading != frag->leading) || (trailing != frag->trailing))
+				fprintf(stderr, "Context reduced to (%ld/%ld) to apply fragment at %d\n",
+					leading, trailing, pos + lines);
+
+			if (size > alloc) {
+				alloc = size + 8192;
+				desc->alloc = alloc;
+				buf = xrealloc(buf, alloc);
+				desc->buffer = buf;
+			}
+			desc->size = size;
+			memmove(buf + offset + newsize, buf + offset + oldsize, size - offset - newsize);
+			memcpy(buf + offset, newlines, newsize);
+			offset = 0;
+
+			break;
+		}
+
+		/* Am I at my context limits? */
+		if ((leading <= p_context) && (trailing <= p_context))
+			break;
+		/* Reduce the number of context lines
+		 * Reduce both leading and trailing if they are equal
+		 * otherwise just reduce the larger context.
+		 */
+		if (leading >= trailing) {
+			remove_first_line(&oldlines, &oldsize);
+			remove_first_line(&newlines, &newsize);
+			pos--;
+			leading--;
+		}
+		if (trailing > leading) {
+			remove_last_line(&oldlines, &oldsize);
+			remove_last_line(&newlines, &newsize);
+			trailing--;
+		}
+	}
+
+	free(old);
+	free(new);
+	return offset;
+}
+
+static char *inflate_it(const void *data, unsigned long size,
+			unsigned long inflated_size)
+{
+	z_stream stream;
+	void *out;
+	int st;
+
+	memset(&stream, 0, sizeof(stream));
+
+	stream.next_in = (unsigned char *)data;
+	stream.avail_in = size;
+	stream.next_out = out = xmalloc(inflated_size);
+	stream.avail_out = inflated_size;
+	inflateInit(&stream);
+	st = inflate(&stream, Z_FINISH);
+	if ((st != Z_STREAM_END) || stream.total_out != inflated_size) {
+		free(out);
+		return NULL;
+	}
+	return out;
+}
+
+static int apply_binary_fragment(struct buffer_desc *desc, struct patch *patch)
+{
+	unsigned long dst_size;
+	struct fragment *fragment = patch->fragments;
+	void *data;
+	void *result;
+
+	data = inflate_it(fragment->patch, fragment->size,
+			  patch->deflate_origlen);
+	if (!data)
+		return error("corrupt patch data");
+	switch (patch->is_binary) {
+	case BINARY_DELTA_DEFLATED:
+		result = patch_delta(desc->buffer, desc->size,
+				     data,
+				     patch->deflate_origlen,
+				     &dst_size);
+		free(desc->buffer);
+		desc->buffer = result;
+		free(data);
+		break;
+	case BINARY_LITERAL_DEFLATED:
+		free(desc->buffer);
+		desc->buffer = data;
+		dst_size = patch->deflate_origlen;
+		break;
+	}
+	if (!desc->buffer)
+		return -1;
+	desc->size = desc->alloc = dst_size;
+	return 0;
+}
+
+static int apply_binary(struct buffer_desc *desc, struct patch *patch)
+{
+	const char *name = patch->old_name ? patch->old_name : patch->new_name;
+	unsigned char sha1[20];
+	unsigned char hdr[50];
+	int hdrlen;
+
+	if (!allow_binary_replacement)
+		return error("cannot apply binary patch to '%s' "
+			     "without --allow-binary-replacement",
+			     name);
+
+	/* For safety, we require patch index line to contain
+	 * full 40-byte textual SHA1 for old and new, at least for now.
+	 */
+	if (strlen(patch->old_sha1_prefix) != 40 ||
+	    strlen(patch->new_sha1_prefix) != 40 ||
+	    get_sha1_hex(patch->old_sha1_prefix, sha1) ||
+	    get_sha1_hex(patch->new_sha1_prefix, sha1))
+		return error("cannot apply binary patch to '%s' "
+			     "without full index line", name);
+
+	if (patch->old_name) {
+		/* See if the old one matches what the patch
+		 * applies to.
+		 */
+		write_sha1_file_prepare(desc->buffer, desc->size,
+					blob_type, sha1, hdr, &hdrlen);
+		if (strcmp(sha1_to_hex(sha1), patch->old_sha1_prefix))
+			return error("the patch applies to '%s' (%s), "
+				     "which does not match the "
+				     "current contents.",
+				     name, sha1_to_hex(sha1));
+	}
+	else {
+		/* Otherwise, the old one must be empty. */
+		if (desc->size)
+			return error("the patch applies to an empty "
+				     "'%s' but it is not empty", name);
+	}
+
+	get_sha1_hex(patch->new_sha1_prefix, sha1);
+	if (!memcmp(sha1, null_sha1, 20)) {
+		free(desc->buffer);
+		desc->alloc = desc->size = 0;
+		desc->buffer = NULL;
+		return 0; /* deletion patch */
+	}
+
+	if (has_sha1_file(sha1)) {
+		/* We already have the postimage */
+		char type[10];
+		unsigned long size;
+
+		free(desc->buffer);
+		desc->buffer = read_sha1_file(sha1, type, &size);
+		if (!desc->buffer)
+			return error("the necessary postimage %s for "
+				     "'%s' cannot be read",
+				     patch->new_sha1_prefix, name);
+		desc->alloc = desc->size = size;
+	}
+	else {
+		/* We have verified desc matches the preimage;
+		 * apply the patch data to it, which is stored
+		 * in the patch->fragments->{patch,size}.
+		 */
+		if (apply_binary_fragment(desc, patch))
+			return error("binary patch does not apply to '%s'",
+				     name);
+
+		/* verify that the result matches */
+		write_sha1_file_prepare(desc->buffer, desc->size, blob_type,
+					sha1, hdr, &hdrlen);
+		if (strcmp(sha1_to_hex(sha1), patch->new_sha1_prefix))
+			return error("binary patch to '%s' creates incorrect result", name);
+	}
+
+	return 0;
+}
+
+static int apply_fragments(struct buffer_desc *desc, struct patch *patch)
+{
+	struct fragment *frag = patch->fragments;
+	const char *name = patch->old_name ? patch->old_name : patch->new_name;
+
+	if (patch->is_binary)
+		return apply_binary(desc, patch);
+
+	while (frag) {
+		if (apply_one_fragment(desc, frag) < 0)
+			return error("patch failed: %s:%ld",
+				     name, frag->oldpos);
+		frag = frag->next;
+	}
+	return 0;
+}
+
+static int apply_data(struct patch *patch, struct stat *st, struct cache_entry *ce)
+{
+	char *buf;
+	unsigned long size, alloc;
+	struct buffer_desc desc;
+
+	size = 0;
+	alloc = 0;
+	buf = NULL;
+	if (cached) {
+		if (ce) {
+			char type[20];
+			buf = read_sha1_file(ce->sha1, type, &size);
+			if (!buf)
+				return error("read of %s failed",
+					     patch->old_name);
+			alloc = size;
+		}
+	}
+	else if (patch->old_name) {
+		size = st->st_size;
+		alloc = size + 8192;
+		buf = xmalloc(alloc);
+		if (read_old_data(st, patch->old_name, buf, alloc) != size)
+			return error("read of %s failed", patch->old_name);
+	}
+
+	desc.size = size;
+	desc.alloc = alloc;
+	desc.buffer = buf;
+	if (apply_fragments(&desc, patch) < 0)
+		return -1;
+	patch->result = desc.buffer;
+	patch->resultsize = desc.size;
+
+	if (patch->is_delete && patch->resultsize)
+		return error("removal patch leaves file contents");
+
+	return 0;
+}
+
+static int check_patch(struct patch *patch)
+{
+	struct stat st;
+	const char *old_name = patch->old_name;
+	const char *new_name = patch->new_name;
+	const char *name = old_name ? old_name : new_name;
+	struct cache_entry *ce = NULL;
+
+	if (old_name) {
+		int changed = 0;
+		int stat_ret = 0;
+		unsigned st_mode = 0;
+
+		if (!cached)
+			stat_ret = lstat(old_name, &st);
+		if (check_index) {
+			int pos = cache_name_pos(old_name, strlen(old_name));
+			if (pos < 0)
+				return error("%s: does not exist in index",
+					     old_name);
+			ce = active_cache[pos];
+			if (stat_ret < 0) {
+				struct checkout costate;
+				if (errno != ENOENT)
+					return error("%s: %s", old_name,
+						     strerror(errno));
+				/* checkout */
+				costate.base_dir = "";
+				costate.base_dir_len = 0;
+				costate.force = 0;
+				costate.quiet = 0;
+				costate.not_new = 0;
+				costate.refresh_cache = 1;
+				if (checkout_entry(ce,
+						   &costate,
+						   NULL) ||
+				    lstat(old_name, &st))
+					return -1;
+			}
+			if (!cached)
+				changed = ce_match_stat(ce, &st, 1);
+			if (changed)
+				return error("%s: does not match index",
+					     old_name);
+			if (cached)
+				st_mode = ntohl(ce->ce_mode);
+		}
+		else if (stat_ret < 0)
+			return error("%s: %s", old_name, strerror(errno));
+
+		if (!cached)
+			st_mode = ntohl(create_ce_mode(st.st_mode));
+
+		if (patch->is_new < 0)
+			patch->is_new = 0;
+		if (!patch->old_mode)
+			patch->old_mode = st_mode;
+		if ((st_mode ^ patch->old_mode) & S_IFMT)
+			return error("%s: wrong type", old_name);
+		if (st_mode != patch->old_mode)
+			fprintf(stderr, "warning: %s has type %o, expected %o\n",
+				old_name, st_mode, patch->old_mode);
+	}
+
+	if (new_name && (patch->is_new | patch->is_rename | patch->is_copy)) {
+		if (check_index && cache_name_pos(new_name, strlen(new_name)) >= 0)
+			return error("%s: already exists in index", new_name);
+		if (!cached) {
+			if (!lstat(new_name, &st))
+				return error("%s: already exists in working directory", new_name);
+			if (errno != ENOENT)
+				return error("%s: %s", new_name, strerror(errno));
+		}
+		if (!patch->new_mode) {
+			if (patch->is_new)
+				patch->new_mode = S_IFREG | 0644;
+			else
+				patch->new_mode = patch->old_mode;
+		}
+	}
+
+	if (new_name && old_name) {
+		int same = !strcmp(old_name, new_name);
+		if (!patch->new_mode)
+			patch->new_mode = patch->old_mode;
+		if ((patch->old_mode ^ patch->new_mode) & S_IFMT)
+			return error("new mode (%o) of %s does not match old mode (%o)%s%s",
+				patch->new_mode, new_name, patch->old_mode,
+				same ? "" : " of ", same ? "" : old_name);
+	}
+
+	if (apply_data(patch, &st, ce) < 0)
+		return error("%s: patch does not apply", name);
+	return 0;
+}
+
+static int check_patch_list(struct patch *patch)
+{
+	int error = 0;
+
+	for (;patch ; patch = patch->next)
+		error |= check_patch(patch);
+	return error;
+}
+
+static inline int is_null_sha1(const unsigned char *sha1)
+{
+	return !memcmp(sha1, null_sha1, 20);
+}
+
+static void show_index_list(struct patch *list)
+{
+	struct patch *patch;
+
+	/* Once we start supporting the reverse patch, it may be
+	 * worth showing the new sha1 prefix, but until then...
+	 */
+	for (patch = list; patch; patch = patch->next) {
+		const unsigned char *sha1_ptr;
+		unsigned char sha1[20];
+		const char *name;
+
+		name = patch->old_name ? patch->old_name : patch->new_name;
+		if (patch->is_new)
+			sha1_ptr = null_sha1;
+		else if (get_sha1(patch->old_sha1_prefix, sha1))
+			die("sha1 information is lacking or useless (%s).",
+			    name);
+		else
+			sha1_ptr = sha1;
+
+		printf("%06o %s	",patch->old_mode, sha1_to_hex(sha1_ptr));
+		if (line_termination && quote_c_style(name, NULL, NULL, 0))
+			quote_c_style(name, NULL, stdout, 0);
+		else
+			fputs(name, stdout);
+		putchar(line_termination);
+	}
+}
+
+static void stat_patch_list(struct patch *patch)
+{
+	int files, adds, dels;
+
+	for (files = adds = dels = 0 ; patch ; patch = patch->next) {
+		files++;
+		adds += patch->lines_added;
+		dels += patch->lines_deleted;
+		show_stats(patch);
+	}
+
+	printf(" %d files changed, %d insertions(+), %d deletions(-)\n", files, adds, dels);
+}
+
+static void numstat_patch_list(struct patch *patch)
+{
+	for ( ; patch; patch = patch->next) {
+		const char *name;
+		name = patch->new_name ? patch->new_name : patch->old_name;
+		printf("%d\t%d\t", patch->lines_added, patch->lines_deleted);
+		if (line_termination && quote_c_style(name, NULL, NULL, 0))
+			quote_c_style(name, NULL, stdout, 0);
+		else
+			fputs(name, stdout);
+		putchar('\n');
+	}
+}
+
+static void show_file_mode_name(const char *newdelete, unsigned int mode, const char *name)
+{
+	if (mode)
+		printf(" %s mode %06o %s\n", newdelete, mode, name);
+	else
+		printf(" %s %s\n", newdelete, name);
+}
+
+static void show_mode_change(struct patch *p, int show_name)
+{
+	if (p->old_mode && p->new_mode && p->old_mode != p->new_mode) {
+		if (show_name)
+			printf(" mode change %06o => %06o %s\n",
+			       p->old_mode, p->new_mode, p->new_name);
+		else
+			printf(" mode change %06o => %06o\n",
+			       p->old_mode, p->new_mode);
+	}
+}
+
+static void show_rename_copy(struct patch *p)
+{
+	const char *renamecopy = p->is_rename ? "rename" : "copy";
+	const char *old, *new;
+
+	/* Find common prefix */
+	old = p->old_name;
+	new = p->new_name;
+	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->old_name thru old is the common prefix, and old and new
+	 * through the end of names are renames
+	 */
+	if (old != p->old_name)
+		printf(" %s %.*s{%s => %s} (%d%%)\n", renamecopy,
+		       (int)(old - p->old_name), p->old_name,
+		       old, new, p->score);
+	else
+		printf(" %s %s => %s (%d%%)\n", renamecopy,
+		       p->old_name, p->new_name, p->score);
+	show_mode_change(p, 0);
+}
+
+static void summary_patch_list(struct patch *patch)
+{
+	struct patch *p;
+
+	for (p = patch; p; p = p->next) {
+		if (p->is_new)
+			show_file_mode_name("create", p->new_mode, p->new_name);
+		else if (p->is_delete)
+			show_file_mode_name("delete", p->old_mode, p->old_name);
+		else {
+			if (p->is_rename || p->is_copy)
+				show_rename_copy(p);
+			else {
+				if (p->score) {
+					printf(" rewrite %s (%d%%)\n",
+					       p->new_name, p->score);
+					show_mode_change(p, 0);
+				}
+				else
+					show_mode_change(p, 1);
+			}
+		}
+	}
+}
+
+static void patch_stats(struct patch *patch)
+{
+	int lines = patch->lines_added + patch->lines_deleted;
+
+	if (lines > max_change)
+		max_change = lines;
+	if (patch->old_name) {
+		int len = quote_c_style(patch->old_name, NULL, NULL, 0);
+		if (!len)
+			len = strlen(patch->old_name);
+		if (len > max_len)
+			max_len = len;
+	}
+	if (patch->new_name) {
+		int len = quote_c_style(patch->new_name, NULL, NULL, 0);
+		if (!len)
+			len = strlen(patch->new_name);
+		if (len > max_len)
+			max_len = len;
+	}
+}
+
+static void remove_file(struct patch *patch)
+{
+	if (write_index) {
+		if (remove_file_from_cache(patch->old_name) < 0)
+			die("unable to remove %s from index", patch->old_name);
+	}
+	if (!cached)
+		unlink(patch->old_name);
+}
+
+static void add_index_file(const char *path, unsigned mode, void *buf, unsigned long size)
+{
+	struct stat st;
+	struct cache_entry *ce;
+	int namelen = strlen(path);
+	unsigned ce_size = cache_entry_size(namelen);
+
+	if (!write_index)
+		return;
+
+	ce = xcalloc(1, ce_size);
+	memcpy(ce->name, path, namelen);
+	ce->ce_mode = create_ce_mode(mode);
+	ce->ce_flags = htons(namelen);
+	if (!cached) {
+		if (lstat(path, &st) < 0)
+			die("unable to stat newly created file %s", path);
+		fill_stat_cache_info(ce, &st);
+	}
+	if (write_sha1_file(buf, size, blob_type, ce->sha1) < 0)
+		die("unable to create backing store for newly created file %s", path);
+	if (add_cache_entry(ce, ADD_CACHE_OK_TO_ADD) < 0)
+		die("unable to add cache entry for %s", path);
+}
+
+static int try_create_file(const char *path, unsigned int mode, const char *buf, unsigned long size)
+{
+	int fd;
+
+	if (S_ISLNK(mode))
+		return symlink(buf, path);
+	fd = open(path, O_CREAT | O_EXCL | O_WRONLY, (mode & 0100) ? 0777 : 0666);
+	if (fd < 0)
+		return -1;
+	while (size) {
+		int written = xwrite(fd, buf, size);
+		if (written < 0)
+			die("writing file %s: %s", path, strerror(errno));
+		if (!written)
+			die("out of space writing file %s", path);
+		buf += written;
+		size -= written;
+	}
+	if (close(fd) < 0)
+		die("closing file %s: %s", path, strerror(errno));
+	return 0;
+}
+
+/*
+ * We optimistically assume that the directories exist,
+ * which is true 99% of the time anyway. If they don't,
+ * we create them and try again.
+ */
+static void create_one_file(char *path, unsigned mode, const char *buf, unsigned long size)
+{
+	if (cached)
+		return;
+	if (!try_create_file(path, mode, buf, size))
+		return;
+
+	if (errno == ENOENT) {
+		if (safe_create_leading_directories(path))
+			return;
+		if (!try_create_file(path, mode, buf, size))
+			return;
+	}
+
+	if (errno == EEXIST) {
+		unsigned int nr = getpid();
+
+		for (;;) {
+			const char *newpath;
+			newpath = mkpath("%s~%u", path, nr);
+			if (!try_create_file(newpath, mode, buf, size)) {
+				if (!rename(newpath, path))
+					return;
+				unlink(newpath);
+				break;
+			}
+			if (errno != EEXIST)
+				break;
+			++nr;
+		}
+	}
+	die("unable to write file %s mode %o", path, mode);
+}
+
+static void create_file(struct patch *patch)
+{
+	char *path = patch->new_name;
+	unsigned mode = patch->new_mode;
+	unsigned long size = patch->resultsize;
+	char *buf = patch->result;
+
+	if (!mode)
+		mode = S_IFREG | 0644;
+	create_one_file(path, mode, buf, size);	
+	add_index_file(path, mode, buf, size);
+}
+
+static void write_out_one_result(struct patch *patch)
+{
+	if (patch->is_delete > 0) {
+		remove_file(patch);
+		return;
+	}
+	if (patch->is_new > 0 || patch->is_copy) {
+		create_file(patch);
+		return;
+	}
+	/*
+	 * Rename or modification boils down to the same
+	 * thing: remove the old, write the new
+	 */
+	remove_file(patch);
+	create_file(patch);
+}
+
+static void write_out_results(struct patch *list, int skipped_patch)
+{
+	if (!list && !skipped_patch)
+		die("No changes");
+
+	while (list) {
+		write_out_one_result(list);
+		list = list->next;
+	}
+}
+
+static struct cache_file cache_file;
+
+static struct excludes {
+	struct excludes *next;
+	const char *path;
+} *excludes;
+
+static int use_patch(struct patch *p)
+{
+	const char *pathname = p->new_name ? p->new_name : p->old_name;
+	struct excludes *x = excludes;
+	while (x) {
+		if (fnmatch(x->path, pathname, 0) == 0)
+			return 0;
+		x = x->next;
+	}
+	if (0 < prefix_length) {
+		int pathlen = strlen(pathname);
+		if (pathlen <= prefix_length ||
+		    memcmp(prefix, pathname, prefix_length))
+			return 0;
+	}
+	return 1;
+}
+
+static int apply_patch(int fd, const char *filename)
+{
+	unsigned long offset, size;
+	char *buffer = read_patch_file(fd, &size);
+	struct patch *list = NULL, **listp = &list;
+	int skipped_patch = 0;
+
+	patch_input_file = filename;
+	if (!buffer)
+		return -1;
+	offset = 0;
+	while (size > 0) {
+		struct patch *patch;
+		int nr;
+
+		patch = xcalloc(1, sizeof(*patch));
+		nr = parse_chunk(buffer + offset, size, patch);
+		if (nr < 0)
+			break;
+		if (use_patch(patch)) {
+			patch_stats(patch);
+			*listp = patch;
+			listp = &patch->next;
+		} else {
+			/* perhaps free it a bit better? */
+			free(patch);
+			skipped_patch++;
+		}
+		offset += nr;
+		size -= nr;
+	}
+
+	if (whitespace_error && (new_whitespace == error_on_whitespace))
+		apply = 0;
+
+	write_index = check_index && apply;
+	if (write_index && newfd < 0)
+		newfd = hold_index_file_for_update(&cache_file, get_index_file());
+	if (check_index) {
+		if (read_cache() < 0)
+			die("unable to read index file");
+	}
+
+	if ((check || apply) && check_patch_list(list) < 0)
+		exit(1);
+
+	if (apply)
+		write_out_results(list, skipped_patch);
+
+	if (show_index_info)
+		show_index_list(list);
+
+	if (diffstat)
+		stat_patch_list(list);
+
+	if (numstat)
+		numstat_patch_list(list);
+
+	if (summary)
+		summary_patch_list(list);
+
+	free(buffer);
+	return 0;
+}
+
+static int git_apply_config(const char *var, const char *value)
+{
+	if (!strcmp(var, "apply.whitespace")) {
+		apply_default_whitespace = strdup(value);
+		return 0;
+	}
+	return git_default_config(var, value);
+}
+
+
+int cmd_apply(int argc, const char **argv, char **envp)
+{
+	int i;
+	int read_stdin = 1;
+	const char *whitespace_option = NULL;
+
+	for (i = 1; i < argc; i++) {
+		const char *arg = argv[i];
+		char *end;
+		int fd;
+
+		if (!strcmp(arg, "-")) {
+			apply_patch(0, "<stdin>");
+			read_stdin = 0;
+			continue;
+		}
+		if (!strncmp(arg, "--exclude=", 10)) {
+			struct excludes *x = xmalloc(sizeof(*x));
+			x->path = arg + 10;
+			x->next = excludes;
+			excludes = x;
+			continue;
+		}
+		if (!strncmp(arg, "-p", 2)) {
+			p_value = atoi(arg + 2);
+			continue;
+		}
+		if (!strcmp(arg, "--no-add")) {
+			no_add = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--stat")) {
+			apply = 0;
+			diffstat = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--allow-binary-replacement") ||
+		    !strcmp(arg, "--binary")) {
+			allow_binary_replacement = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--numstat")) {
+			apply = 0;
+			numstat = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--summary")) {
+			apply = 0;
+			summary = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--check")) {
+			apply = 0;
+			check = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--index")) {
+			check_index = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--cached")) {
+			check_index = 1;
+			cached = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--apply")) {
+			apply = 1;
+			continue;
+		}
+		if (!strcmp(arg, "--index-info")) {
+			apply = 0;
+			show_index_info = 1;
+			continue;
+		}
+		if (!strcmp(arg, "-z")) {
+			line_termination = 0;
+			continue;
+		}
+		if (!strncmp(arg, "-C", 2)) {
+			p_context = strtoul(arg + 2, &end, 0);
+			if (*end != '\0')
+				die("unrecognized context count '%s'", arg + 2);
+			continue;
+		}
+		if (!strncmp(arg, "--whitespace=", 13)) {
+			whitespace_option = arg + 13;
+			parse_whitespace_option(arg + 13);
+			continue;
+		}
+
+		if (check_index && prefix_length < 0) {
+			prefix = setup_git_directory();
+			prefix_length = prefix ? strlen(prefix) : 0;
+			git_config(git_apply_config);
+			if (!whitespace_option && apply_default_whitespace)
+				parse_whitespace_option(apply_default_whitespace);
+		}
+		if (0 < prefix_length)
+			arg = prefix_filename(prefix, prefix_length, arg);
+
+		fd = open(arg, O_RDONLY);
+		if (fd < 0)
+			usage(apply_usage);
+		read_stdin = 0;
+		set_default_whitespace_mode(whitespace_option);
+		apply_patch(fd, arg);
+		close(fd);
+	}
+	set_default_whitespace_mode(whitespace_option);
+	if (read_stdin)
+		apply_patch(0, "<stdin>");
+	if (whitespace_error) {
+		if (squelch_whitespace_errors &&
+		    squelch_whitespace_errors < whitespace_error) {
+			int squelched =
+				whitespace_error - squelch_whitespace_errors;
+			fprintf(stderr, "warning: squelched %d whitespace error%s\n",
+				squelched,
+				squelched == 1 ? "" : "s");
+		}
+		if (new_whitespace == error_on_whitespace)
+			die("%d line%s add%s trailing whitespaces.",
+			    whitespace_error,
+			    whitespace_error == 1 ? "" : "s",
+			    whitespace_error == 1 ? "s" : "");
+		if (applied_after_stripping)
+			fprintf(stderr, "warning: %d line%s applied after"
+				" stripping trailing whitespaces.\n",
+				applied_after_stripping,
+				applied_after_stripping == 1 ? "" : "s");
+		else if (whitespace_error)
+			fprintf(stderr, "warning: %d line%s add%s trailing"
+				" whitespaces.\n",
+				whitespace_error,
+				whitespace_error == 1 ? "" : "s",
+				whitespace_error == 1 ? "s" : "");
+	}
+
+	if (write_index) {
+		if (write_cache(newfd, active_cache, active_nr) ||
+		    commit_index_file(&cache_file))
+			die("Unable to write new cachefile");
+	}
+
+	return 0;
+}