git

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/*
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 * "diff --no-index" support
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 * Copyright (c) 2007 by Johannes Schindelin
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 * Copyright (c) 2008 by Junio C Hamano
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 */
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#include "git-compat-util.h"
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#include "abspath.h"
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#include "color.h"
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#include "commit.h"
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#include "diff.h"
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#include "diffcore.h"
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#include "gettext.h"
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#include "revision.h"
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#include "parse-options.h"
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#include "string-list.h"
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#include "dir.h"
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19
static int read_directory_contents(const char *path, struct string_list *list)
20
{
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	DIR *dir;
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	struct dirent *e;
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24
	if (!(dir = opendir(path)))
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		return error("Could not open directory %s", path);
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27
	while ((e = readdir_skip_dot_and_dotdot(dir)))
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		string_list_insert(list, e->d_name);
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30
	closedir(dir);
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	return 0;
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}
33

34
/*
35
 * This should be "(standard input)" or something, but it will
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 * probably expose many more breakages in the way no-index code
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 * is bolted onto the diff callchain.
38
 */
39
static const char file_from_standard_input[] = "-";
40

41
/*
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 * For paths given on the command-line we treat "-" as stdin and named
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 * pipes and symbolic links to named pipes specially.
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 */
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enum special {
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	SPECIAL_NONE,
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	SPECIAL_STDIN,
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	SPECIAL_PIPE,
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};
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51
static int get_mode(const char *path, int *mode, enum special *special)
52
{
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	struct stat st;
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55
	if (!path || !strcmp(path, "/dev/null")) {
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		*mode = 0;
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#ifdef GIT_WINDOWS_NATIVE
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	} else if (!strcasecmp(path, "nul")) {
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		*mode = 0;
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#endif
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	} else if (path == file_from_standard_input) {
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		*mode = create_ce_mode(0666);
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		*special = SPECIAL_STDIN;
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	} else if (lstat(path, &st)) {
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		return error("Could not access '%s'", path);
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	} else {
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		*mode = st.st_mode;
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	}
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	/*
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	 * For paths on the command-line treat named pipes and symbolic
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	 * links that resolve to a named pipe specially.
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	 */
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	if (special &&
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	    (S_ISFIFO(*mode) ||
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	     (S_ISLNK(*mode) && !stat(path, &st) && S_ISFIFO(st.st_mode)))) {
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		*mode = create_ce_mode(0666);
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		*special = SPECIAL_PIPE;
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	}
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	return 0;
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}
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static void populate_common(struct diff_filespec *s, struct strbuf *buf)
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{
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	size_t size = 0;
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	s->should_munmap = 0;
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	s->data = strbuf_detach(buf, &size);
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	s->size = size;
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	s->should_free = 1;
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	s->is_stdin = 1;
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}
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static void populate_from_pipe(struct diff_filespec *s)
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{
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	struct strbuf buf = STRBUF_INIT;
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	int fd = xopen(s->path, O_RDONLY);
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	if (strbuf_read(&buf, fd, 0) < 0)
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		die_errno("error while reading from '%s'", s->path);
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	close(fd);
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	populate_common(s, &buf);
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}
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static void populate_from_stdin(struct diff_filespec *s)
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{
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	struct strbuf buf = STRBUF_INIT;
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	if (strbuf_read(&buf, 0, 0) < 0)
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		die_errno("error while reading from stdin");
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	populate_common(s, &buf);
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}
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static struct diff_filespec *noindex_filespec(const char *name, int mode,
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					      enum special special)
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{
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	struct diff_filespec *s;
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119
	if (!name)
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		name = "/dev/null";
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	s = alloc_filespec(name);
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	fill_filespec(s, null_oid(), 0, mode);
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	if (special == SPECIAL_STDIN)
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		populate_from_stdin(s);
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	else if (special == SPECIAL_PIPE)
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		populate_from_pipe(s);
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	return s;
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}
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static int queue_diff(struct diff_options *o,
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		      const char *name1, const char *name2, int recursing)
132
{
133
	int mode1 = 0, mode2 = 0;
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	enum special special1 = SPECIAL_NONE, special2 = SPECIAL_NONE;
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	/* Paths can only be special if we're not recursing. */
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	if (get_mode(name1, &mode1, recursing ? NULL : &special1) ||
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	    get_mode(name2, &mode2, recursing ? NULL : &special2))
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		return -1;
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141
	if (mode1 && mode2 && S_ISDIR(mode1) != S_ISDIR(mode2)) {
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		struct diff_filespec *d1, *d2;
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144
		if (S_ISDIR(mode1)) {
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			/* 2 is file that is created */
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			d1 = noindex_filespec(NULL, 0, SPECIAL_NONE);
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			d2 = noindex_filespec(name2, mode2, special2);
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			name2 = NULL;
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			mode2 = 0;
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		} else {
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			/* 1 is file that is deleted */
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			d1 = noindex_filespec(name1, mode1, special1);
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			d2 = noindex_filespec(NULL, 0, SPECIAL_NONE);
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			name1 = NULL;
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			mode1 = 0;
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		}
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		/* emit that file */
158
		diff_queue(&diff_queued_diff, d1, d2);
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160
		/* and then let the entire directory be created or deleted */
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	}
162

163
	if (S_ISDIR(mode1) || S_ISDIR(mode2)) {
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		struct strbuf buffer1 = STRBUF_INIT;
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		struct strbuf buffer2 = STRBUF_INIT;
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		struct string_list p1 = STRING_LIST_INIT_DUP;
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		struct string_list p2 = STRING_LIST_INIT_DUP;
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		int i1, i2, ret = 0;
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		size_t len1 = 0, len2 = 0;
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171
		if (name1 && read_directory_contents(name1, &p1))
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			return -1;
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		if (name2 && read_directory_contents(name2, &p2)) {
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			string_list_clear(&p1, 0);
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			return -1;
176
		}
177

178
		if (name1) {
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			strbuf_addstr(&buffer1, name1);
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			strbuf_complete(&buffer1, '/');
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			len1 = buffer1.len;
182
		}
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184
		if (name2) {
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			strbuf_addstr(&buffer2, name2);
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			strbuf_complete(&buffer2, '/');
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			len2 = buffer2.len;
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		}
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190
		for (i1 = i2 = 0; !ret && (i1 < p1.nr || i2 < p2.nr); ) {
191
			const char *n1, *n2;
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			int comp;
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194
			strbuf_setlen(&buffer1, len1);
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			strbuf_setlen(&buffer2, len2);
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197
			if (i1 == p1.nr)
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				comp = 1;
199
			else if (i2 == p2.nr)
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				comp = -1;
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			else
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				comp = strcmp(p1.items[i1].string, p2.items[i2].string);
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204
			if (comp > 0)
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				n1 = NULL;
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			else {
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				strbuf_addstr(&buffer1, p1.items[i1++].string);
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				n1 = buffer1.buf;
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			}
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211
			if (comp < 0)
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				n2 = NULL;
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			else {
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				strbuf_addstr(&buffer2, p2.items[i2++].string);
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				n2 = buffer2.buf;
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			}
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218
			ret = queue_diff(o, n1, n2, 1);
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		}
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		string_list_clear(&p1, 0);
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		string_list_clear(&p2, 0);
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		strbuf_release(&buffer1);
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		strbuf_release(&buffer2);
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		return ret;
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	} else {
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		struct diff_filespec *d1, *d2;
228

229
		if (o->flags.reverse_diff) {
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			SWAP(mode1, mode2);
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			SWAP(name1, name2);
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			SWAP(special1, special2);
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		}
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		d1 = noindex_filespec(name1, mode1, special1);
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		d2 = noindex_filespec(name2, mode2, special2);
237
		diff_queue(&diff_queued_diff, d1, d2);
238
		return 0;
239
	}
240
}
241

242
/* append basename of F to D */
243
static void append_basename(struct strbuf *path, const char *dir, const char *file)
244
{
245
	const char *tail = strrchr(file, '/');
246

247
	strbuf_addstr(path, dir);
248
	while (path->len && path->buf[path->len - 1] == '/')
249
		path->len--;
250
	strbuf_addch(path, '/');
251
	strbuf_addstr(path, tail ? tail + 1 : file);
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}
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254
/*
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 * DWIM "diff D F" into "diff D/F F" and "diff F D" into "diff F D/F"
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 * Note that we append the basename of F to D/, so "diff a/b/file D"
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 * becomes "diff a/b/file D/file", not "diff a/b/file D/a/b/file".
258
 */
259
static void fixup_paths(const char **path, struct strbuf *replacement)
260
{
261
	struct stat st;
262
	unsigned int isdir0 = 0, isdir1 = 0;
263
	unsigned int ispipe0 = 0, ispipe1 = 0;
264

265
	if (path[0] != file_from_standard_input && !stat(path[0], &st)) {
266
		isdir0 = S_ISDIR(st.st_mode);
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		ispipe0 = S_ISFIFO(st.st_mode);
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	}
269

270
	if (path[1] != file_from_standard_input && !stat(path[1], &st)) {
271
		isdir1 = S_ISDIR(st.st_mode);
272
		ispipe1 = S_ISFIFO(st.st_mode);
273
	}
274

275
	if ((path[0] == file_from_standard_input && isdir1) ||
276
	    (isdir0 && path[1] == file_from_standard_input))
277
		die(_("cannot compare stdin to a directory"));
278

279
	if ((isdir0 && ispipe1) || (ispipe0 && isdir1))
280
		die(_("cannot compare a named pipe to a directory"));
281

282
	if (isdir0 == isdir1)
283
		return;
284
	if (isdir0) {
285
		append_basename(replacement, path[0], path[1]);
286
		path[0] = replacement->buf;
287
	} else {
288
		append_basename(replacement, path[1], path[0]);
289
		path[1] = replacement->buf;
290
	}
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}
292

293
static const char * const diff_no_index_usage[] = {
294
	N_("git diff --no-index [<options>] <path> <path>"),
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	NULL
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};
297

298
int diff_no_index(struct rev_info *revs,
299
		  int implicit_no_index,
300
		  int argc, const char **argv)
301
{
302
	int i, no_index;
303
	int ret = 1;
304
	const char *paths[2];
305
	char *to_free[ARRAY_SIZE(paths)] = { 0 };
306
	struct strbuf replacement = STRBUF_INIT;
307
	const char *prefix = revs->prefix;
308
	struct option no_index_options[] = {
309
		OPT_BOOL_F(0, "no-index", &no_index, "",
310
			   PARSE_OPT_NONEG | PARSE_OPT_HIDDEN),
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		OPT_END(),
312
	};
313
	struct option *options;
314

315
	options = add_diff_options(no_index_options, &revs->diffopt);
316
	argc = parse_options(argc, argv, revs->prefix, options,
317
			     diff_no_index_usage, 0);
318
	if (argc != 2) {
319
		if (implicit_no_index)
320
			warning(_("Not a git repository. Use --no-index to "
321
				  "compare two paths outside a working tree"));
322
		usage_with_options(diff_no_index_usage, options);
323
	}
324
	FREE_AND_NULL(options);
325
	for (i = 0; i < 2; i++) {
326
		const char *p = argv[i];
327
		if (!strcmp(p, "-"))
328
			/*
329
			 * stdin should be spelled as "-"; if you have
330
			 * path that is "-", spell it as "./-".
331
			 */
332
			p = file_from_standard_input;
333
		else if (prefix)
334
			p = to_free[i] = prefix_filename(prefix, p);
335
		paths[i] = p;
336
	}
337

338
	fixup_paths(paths, &replacement);
339

340
	revs->diffopt.skip_stat_unmatch = 1;
341
	if (!revs->diffopt.output_format)
342
		revs->diffopt.output_format = DIFF_FORMAT_PATCH;
343

344
	revs->diffopt.flags.no_index = 1;
345

346
	revs->diffopt.flags.relative_name = 1;
347
	revs->diffopt.prefix = prefix;
348

349
	revs->max_count = -2;
350
	diff_setup_done(&revs->diffopt);
351

352
	setup_diff_pager(&revs->diffopt);
353
	revs->diffopt.flags.exit_with_status = 1;
354

355
	if (queue_diff(&revs->diffopt, paths[0], paths[1], 0))
356
		goto out;
357
	diff_set_mnemonic_prefix(&revs->diffopt, "1/", "2/");
358
	diffcore_std(&revs->diffopt);
359
	diff_flush(&revs->diffopt);
360

361
	/*
362
	 * The return code for --no-index imitates diff(1):
363
	 * 0 = no changes, 1 = changes, else error
364
	 */
365
	ret = diff_result_code(&revs->diffopt);
366

367
out:
368
	for (i = 0; i < ARRAY_SIZE(to_free); i++)
369
		free(to_free[i]);
370
	strbuf_release(&replacement);
371
	return ret;
372
}
373