builtin-ls-files.c - git - Git at Google

 /*
  * This merges the file listing in the directory cache index
  * with the actual working directory list, and shows different
  * combinations of the two.
  *
  * Copyright (C) Linus Torvalds, 2005
  */
 #include "cache.h"
 #include "quote.h"
 #include "dir.h"
 #include "builtin.h"
 #include "tree.h"
 #include "parse-options.h"

 static int abbrev;
 static int show_deleted;
 static int show_cached;
 static int show_others;
 static int show_stage;
 static int show_unmerged;
 static int show_modified;
 static int show_killed;
 static int show_valid_bit;
 static int line_terminator = '\n';

 static int prefix_len;
 static int prefix_offset;
 static const char **pathspec;
 static int error_unmatch;
 static char *ps_matched;
 static const char *with_tree;
 static int exc_given;

 static const char *tag_cached = "";
 static const char *tag_unmerged = "";
 static const char *tag_removed = "";
 static const char *tag_other = "";
 static const char *tag_killed = "";
 static const char *tag_modified = "";

 static void show_dir_entry(const char *tag, struct dir_entry *ent)
 {
 	int len = prefix_len;
 	int offset = prefix_offset;

 	if (len >= ent->len)
 		die("git ls-files: internal error - directory entry not superset of prefix");

 	if (!match_pathspec(pathspec, ent->name, ent->len, len, ps_matched))
 		return;

 	fputs(tag, stdout);
 	write_name_quoted(ent->name + offset, stdout, line_terminator);
 }

 static void show_other_files(struct dir_struct *dir)
 {
 	int i;

 	for (i = 0; i < dir->nr; i++) {
 		struct dir_entry *ent = dir->entries[i];
 		if (!cache_name_is_other(ent->name, ent->len))
 			continue;
 		show_dir_entry(tag_other, ent);
 	}
 }

 static void show_killed_files(struct dir_struct *dir)
 {
 	int i;
 	for (i = 0; i < dir->nr; i++) {
 		struct dir_entry *ent = dir->entries[i];
 		char *cp, *sp;
 		int pos, len, killed = 0;

 		for (cp = ent->name; cp - ent->name < ent->len; cp = sp + 1) {
 			sp = strchr(cp, '/');
 			if (!sp) {
 				/* If ent->name is prefix of an entry in the
 				 * cache, it will be killed.
 				 */
 				pos = cache_name_pos(ent->name, ent->len);
 				if (0 <= pos)
 					die("bug in show-killed-files");
 				pos = -pos - 1;
 				while (pos < active_nr &&
 				       ce_stage(active_cache[pos]))
 					pos++; /* skip unmerged */
 				if (active_nr <= pos)
 					break;
 				/* pos points at a name immediately after
 				 * ent->name in the cache.  Does it expect
 				 * ent->name to be a directory?
 				 */
 				len = ce_namelen(active_cache[pos]);
 				if ((ent->len < len) &&
 				    !strncmp(active_cache[pos]->name,
 					     ent->name, ent->len) &&
 				    active_cache[pos]->name[ent->len] == '/')
 					killed = 1;
 				break;
 			}
 			if (0 <= cache_name_pos(ent->name, sp - ent->name)) {
 				/* If any of the leading directories in
 				 * ent->name is registered in the cache,
 				 * ent->name will be killed.
 				 */
 				killed = 1;
 				break;
 			}
 		}
 		if (killed)
 			show_dir_entry(tag_killed, dir->entries[i]);
 	}
 }

 static void show_ce_entry(const char *tag, struct cache_entry *ce)
 {
 	int len = prefix_len;
 	int offset = prefix_offset;

 	if (len >= ce_namelen(ce))
 		die("git ls-files: internal error - cache entry not superset of prefix");

 	if (!match_pathspec(pathspec, ce->name, ce_namelen(ce), len, ps_matched))
 		return;

 	if (tag && *tag && show_valid_bit &&
 	    (ce->ce_flags & CE_VALID)) {
 		static char alttag[4];
 		memcpy(alttag, tag, 3);
 		if (isalpha(tag[0]))
 			alttag[0] = tolower(tag[0]);
 		else if (tag[0] == '?')
 			alttag[0] = '!';
 		else {
 			alttag[0] = 'v';
 			alttag[1] = tag[0];
 			alttag[2] = ' ';
 			alttag[3] = 0;
 		}
 		tag = alttag;
 	}

 	if (!show_stage) {
 		fputs(tag, stdout);
 	} else {
 		printf("%s%06o %s %d\t",
 		       tag,
 		       ce->ce_mode,
 		       abbrev ? find_unique_abbrev(ce->sha1,abbrev)
 				: sha1_to_hex(ce->sha1),
 		       ce_stage(ce));
 	}
 	write_name_quoted(ce->name + offset, stdout, line_terminator);
 }

 static void show_files(struct dir_struct *dir, const char *prefix)
 {
 	int i;

 	/* For cached/deleted files we don't need to even do the readdir */
 	if (show_others || show_killed) {
 		const char *path = ".", *base = "";
 		int baselen = prefix_len;

 		if (baselen)
 			path = base = prefix;
 		read_directory(dir, path, base, baselen, pathspec);
 		if (show_others)
 			show_other_files(dir);
 		if (show_killed)
 			show_killed_files(dir);
 	}
 	if (show_cached | show_stage) {
 		for (i = 0; i < active_nr; i++) {
 			struct cache_entry *ce = active_cache[i];
 			int dtype = ce_to_dtype(ce);
 			if (excluded(dir, ce->name, &dtype) !=
 					!!(dir->flags & DIR_SHOW_IGNORED))
 				continue;
 			if (show_unmerged && !ce_stage(ce))
 				continue;
 			if (ce->ce_flags & CE_UPDATE)
 				continue;
 			show_ce_entry(ce_stage(ce) ? tag_unmerged : tag_cached, ce);
 		}
 	}
 	if (show_deleted | show_modified) {
 		for (i = 0; i < active_nr; i++) {
 			struct cache_entry *ce = active_cache[i];
 			struct stat st;
 			int err;
 			int dtype = ce_to_dtype(ce);
 			if (excluded(dir, ce->name, &dtype) !=
 					!!(dir->flags & DIR_SHOW_IGNORED))
 				continue;
 			if (ce->ce_flags & CE_UPDATE)
 				continue;
 			err = lstat(ce->name, &st);
 			if (show_deleted && err)
 				show_ce_entry(tag_removed, ce);
 			if (show_modified && ce_modified(ce, &st, 0))
 				show_ce_entry(tag_modified, ce);
 		}
 	}
 }

 /*
  * Prune the index to only contain stuff starting with "prefix"
  */
 static void prune_cache(const char *prefix)
 {
 	int pos = cache_name_pos(prefix, prefix_len);
 	unsigned int first, last;

 	if (pos < 0)
 		pos = -pos-1;
 	memmove(active_cache, active_cache + pos,
 		(active_nr - pos) * sizeof(struct cache_entry *));
 	active_nr -= pos;
 	first = 0;
 	last = active_nr;
 	while (last > first) {
 		int next = (last + first) >> 1;
 		struct cache_entry *ce = active_cache[next];
 		if (!strncmp(ce->name, prefix, prefix_len)) {
 			first = next+1;
 			continue;
 		}
 		last = next;
 	}
 	active_nr = last;
 }

 static const char *verify_pathspec(const char *prefix)
 {
 	const char **p, *n, *prev;
 	unsigned long max;

 	prev = NULL;
 	max = PATH_MAX;
 	for (p = pathspec; (n = *p) != NULL; p++) {
 		int i, len = 0;
 		for (i = 0; i < max; i++) {
 			char c = n[i];
 			if (prev && prev[i] != c)
 				break;
 			if (!c || c == '*' || c == '?')
 				break;
 			if (c == '/')
 				len = i+1;
 		}
 		prev = n;
 		if (len < max) {
 			max = len;
 			if (!max)
 				break;
 		}
 	}

 	if (prefix_offset > max || memcmp(prev, prefix, prefix_offset))
 		die("git ls-files: cannot generate relative filenames containing '..'");

 	prefix_len = max;
 	return max ? xmemdupz(prev, max) : NULL;
 }

 static void strip_trailing_slash_from_submodules(void)
 {
 	const char **p;

 	for (p = pathspec; *p != NULL; p++) {
 		int len = strlen(*p), pos;

 		if (len < 1 || (*p)[len - 1] != '/')
 			continue;
 		pos = cache_name_pos(*p, len - 1);
 		if (pos >= 0 && S_ISGITLINK(active_cache[pos]->ce_mode))
 			*p = xstrndup(*p, len - 1);
 	}
 }

 /*
  * Read the tree specified with --with-tree option
  * (typically, HEAD) into stage #1 and then
  * squash them down to stage #0.  This is used for
  * --error-unmatch to list and check the path patterns
  * that were given from the command line.  We are not
  * going to write this index out.
  */
 void overlay_tree_on_cache(const char *tree_name, const char *prefix)
 {
 	struct tree *tree;
 	unsigned char sha1[20];
 	const char **match;
 	struct cache_entry *last_stage0 = NULL;
 	int i;

 	if (get_sha1(tree_name, sha1))
 		die("tree-ish %s not found.", tree_name);
 	tree = parse_tree_indirect(sha1);
 	if (!tree)
 		die("bad tree-ish %s", tree_name);

 	/* Hoist the unmerged entries up to stage #3 to make room */
 	for (i = 0; i < active_nr; i++) {
 		struct cache_entry *ce = active_cache[i];
 		if (!ce_stage(ce))
 			continue;
 		ce->ce_flags |= CE_STAGEMASK;
 	}

 	if (prefix) {
 		static const char *(matchbuf[2]);
 		matchbuf[0] = prefix;
 		matchbuf[1] = NULL;
 		match = matchbuf;
 	} else
 		match = NULL;
 	if (read_tree(tree, 1, match))
 		die("unable to read tree entries %s", tree_name);

 	for (i = 0; i < active_nr; i++) {
 		struct cache_entry *ce = active_cache[i];
 		switch (ce_stage(ce)) {
 		case 0:
 			last_stage0 = ce;
 			/* fallthru */
 		default:
 			continue;
 		case 1:
 			/*
 			 * If there is stage #0 entry for this, we do not
 			 * need to show it.  We use CE_UPDATE bit to mark
 			 * such an entry.
 			 */
 			if (last_stage0 &&
 			    !strcmp(last_stage0->name, ce->name))
 				ce->ce_flags |= CE_UPDATE;
 		}
 	}
 }

 int report_path_error(const char *ps_matched, const char **pathspec, int prefix_offset)
 {
 	/*
 	 * Make sure all pathspec matched; otherwise it is an error.
 	 */
 	int num, errors = 0;
 	for (num = 0; pathspec[num]; num++) {
 		int other, found_dup;

 		if (ps_matched[num])
 			continue;
 		/*
 		 * The caller might have fed identical pathspec
 		 * twice.  Do not barf on such a mistake.
 		 */
 		for (found_dup = other = 0;
 		     !found_dup && pathspec[other];
 		     other++) {
 			if (other == num || !ps_matched[other])
 				continue;
 			if (!strcmp(pathspec[other], pathspec[num]))
 				/*
 				 * Ok, we have a match already.
 				 */
 				found_dup = 1;
 		}
 		if (found_dup)
 			continue;

 		error("pathspec '%s' did not match any file(s) known to git.",
 		      pathspec[num] + prefix_offset);
 		errors++;
 	}
 	return errors;
 }

 static const char * const ls_files_usage[] = {
 	"git ls-files [options] [<file>]*",
 	NULL
 };

 static int option_parse_z(const struct option *opt,
 			  const char *arg, int unset)
 {
 	line_terminator = unset ? '\n' : '\0';

 	return 0;
 }

 static int option_parse_exclude(const struct option *opt,
 				const char *arg, int unset)
 {
 	struct exclude_list *list = opt->value;

 	exc_given = 1;
 	add_exclude(arg, "", 0, list);

 	return 0;
 }

 static int option_parse_exclude_from(const struct option *opt,
 				     const char *arg, int unset)
 {
 	struct dir_struct *dir = opt->value;

 	exc_given = 1;
 	add_excludes_from_file(dir, arg);

 	return 0;
 }

 static int option_parse_exclude_standard(const struct option *opt,
 					 const char *arg, int unset)
 {
 	struct dir_struct *dir = opt->value;

 	exc_given = 1;
 	setup_standard_excludes(dir);

 	return 0;
 }

 int cmd_ls_files(int argc, const char **argv, const char *prefix)
 {
 	int require_work_tree = 0, show_tag = 0;
 	struct dir_struct dir;
 	struct option builtin_ls_files_options[] = {
 		{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
 			"paths are separated with NUL character",
 			PARSE_OPT_NOARG, option_parse_z },
 		OPT_BOOLEAN('t', NULL, &show_tag,
 			"identify the file status with tags"),
 		OPT_BOOLEAN('v', NULL, &show_valid_bit,
 			"use lowercase letters for 'assume unchanged' files"),
 		OPT_BOOLEAN('c', "cached", &show_cached,
 			"show cached files in the output (default)"),
 		OPT_BOOLEAN('d', "deleted", &show_deleted,
 			"show deleted files in the output"),
 		OPT_BOOLEAN('m', "modified", &show_modified,
 			"show modified files in the output"),
 		OPT_BOOLEAN('o', "others", &show_others,
 			"show other files in the output"),
 		OPT_BIT('i', "ignored", &dir.flags,
 			"show ignored files in the output",
 			DIR_SHOW_IGNORED),
 		OPT_BOOLEAN('s', "stage", &show_stage,
 			"show staged contents' object name in the output"),
 		OPT_BOOLEAN('k', "killed", &show_killed,
 			"show files on the filesystem that need to be removed"),
 		OPT_BIT(0, "directory", &dir.flags,
 			"show 'other' directories' name only",
 			DIR_SHOW_OTHER_DIRECTORIES),
 		OPT_BIT(0, "no-empty-directory", &dir.flags,
 			"don't show empty directories",
 			DIR_HIDE_EMPTY_DIRECTORIES),
 		OPT_BOOLEAN('u', "unmerged", &show_unmerged,
 			"show unmerged files in the output"),
 		{ OPTION_CALLBACK, 'x', "exclude", &dir.exclude_list[EXC_CMDL], "pattern",
 			"skip files matching pattern",
 			0, option_parse_exclude },
 		{ OPTION_CALLBACK, 'X', "exclude-from", &dir, "file",
 			"exclude patterns are read from <file>",
 			0, option_parse_exclude_from },
 		OPT_STRING(0, "exclude-per-directory", &dir.exclude_per_dir, "file",
 			"read additional per-directory exclude patterns in <file>"),
 		{ OPTION_CALLBACK, 0, "exclude-standard", &dir, NULL,
 			"add the standard git exclusions",
 			PARSE_OPT_NOARG, option_parse_exclude_standard },
 		{ OPTION_SET_INT, 0, "full-name", &prefix_offset, NULL,
 			"make the output relative to the project top directory",
 			PARSE_OPT_NOARG | PARSE_OPT_NONEG, NULL },
 		OPT_BOOLEAN(0, "error-unmatch", &error_unmatch,
 			"if any <file> is not in the index, treat this as an error"),
 		OPT_STRING(0, "with-tree", &with_tree, "tree-ish",
 			"pretend that paths removed since <tree-ish> are still present"),
 		OPT__ABBREV(&abbrev),
 		OPT_END()
 	};

 	memset(&dir, 0, sizeof(dir));
 	if (prefix)
 		prefix_offset = strlen(prefix);
 	git_config(git_default_config, NULL);

 	argc = parse_options(argc, argv, builtin_ls_files_options,
 			ls_files_usage, 0);
 	if (show_tag || show_valid_bit) {
 		tag_cached = "H ";
 		tag_unmerged = "M ";
 		tag_removed = "R ";
 		tag_modified = "C ";
 		tag_other = "? ";
 		tag_killed = "K ";
 	}
 	if (show_modified || show_others || show_deleted || (dir.flags & DIR_SHOW_IGNORED) || show_killed)
 		require_work_tree = 1;
 	if (show_unmerged)
 		/*
 		 * There's no point in showing unmerged unless
 		 * you also show the stage information.
 		 */
 		show_stage = 1;
 	if (dir.exclude_per_dir)
 		exc_given = 1;

 	if (require_work_tree && !is_inside_work_tree())
 		setup_work_tree();

 	pathspec = get_pathspec(prefix, argv);

 	/* be nice with submodule paths ending in a slash */
 	read_cache();
 	if (pathspec)
 		strip_trailing_slash_from_submodules();

 	/* Verify that the pathspec matches the prefix */
 	if (pathspec)
 		prefix = verify_pathspec(prefix);

 	/* Treat unmatching pathspec elements as errors */
 	if (pathspec && error_unmatch) {
 		int num;
 		for (num = 0; pathspec[num]; num++)
 			;
 		ps_matched = xcalloc(1, num);
 	}

 	if ((dir.flags & DIR_SHOW_IGNORED) && !exc_given) {
 		fprintf(stderr, "%s: --ignored needs some exclude pattern\n",
 			argv[0]);
 		exit(1);
 	}

 	/* With no flags, we default to showing the cached files */
 	if (!(show_stage | show_deleted | show_others | show_unmerged |
 	      show_killed | show_modified))
 		show_cached = 1;

 	if (prefix)
 		prune_cache(prefix);
 	if (with_tree) {
 		/*
 		 * Basic sanity check; show-stages and show-unmerged
 		 * would not make any sense with this option.
 		 */
 		if (show_stage || show_unmerged)
 			die("ls-files --with-tree is incompatible with -s or -u");
 		overlay_tree_on_cache(with_tree, prefix);
 	}
 	show_files(&dir, prefix);

 	if (ps_matched) {
 		int bad;
 		bad = report_path_error(ps_matched, pathspec, prefix_offset);
 		if (bad)
 			fprintf(stderr, "Did you forget to 'git add'?\n");

 		return bad ? 1 : 0;
 	}

 	return 0;
 }
	/*
	* This merges the file listing in the directory cache index
	* with the actual working directory list, and shows different
	* combinations of the two.
	*
	* Copyright (C) Linus Torvalds, 2005
	*/
	#include "cache.h"
	#include "quote.h"
	#include "dir.h"
	#include "builtin.h"
	#include "tree.h"
	#include "parse-options.h"

	static int abbrev;
	static int show_deleted;
	static int show_cached;
	static int show_others;
	static int show_stage;
	static int show_unmerged;
	static int show_modified;
	static int show_killed;
	static int show_valid_bit;
	static int line_terminator = '\n';

	static int prefix_len;
	static int prefix_offset;
	static const char **pathspec;
	static int error_unmatch;
	static char *ps_matched;
	static const char *with_tree;
	static int exc_given;

	static const char *tag_cached = "";
	static const char *tag_unmerged = "";
	static const char *tag_removed = "";
	static const char *tag_other = "";
	static const char *tag_killed = "";
	static const char *tag_modified = "";

	static void show_dir_entry(const char tag, struct dir_entry ent)
	{
	int len = prefix_len;
	int offset = prefix_offset;

	if (len >= ent->len)
	die("git ls-files: internal error - directory entry not superset of prefix");

	if (!match_pathspec(pathspec, ent->name, ent->len, len, ps_matched))
	return;

	fputs(tag, stdout);
	write_name_quoted(ent->name + offset, stdout, line_terminator);
	}

	static void show_other_files(struct dir_struct *dir)
	{
	int i;

	for (i = 0; i < dir->nr; i++) {
	struct dir_entry *ent = dir->entries[i];
	if (!cache_name_is_other(ent->name, ent->len))
	continue;
	show_dir_entry(tag_other, ent);
	}
	}

	static void show_killed_files(struct dir_struct *dir)
	{
	int i;
	for (i = 0; i < dir->nr; i++) {
	struct dir_entry *ent = dir->entries[i];
	char cp, sp;
	int pos, len, killed = 0;

	for (cp = ent->name; cp - ent->name < ent->len; cp = sp + 1) {
	sp = strchr(cp, '/');
	if (!sp) {
	/* If ent->name is prefix of an entry in the
	* cache, it will be killed.
	*/
	pos = cache_name_pos(ent->name, ent->len);
	if (0 <= pos)
	die("bug in show-killed-files");
	pos = -pos - 1;
	while (pos < active_nr &&
	ce_stage(active_cache[pos]))
	pos++; /* skip unmerged */
	if (active_nr <= pos)
	break;
	/* pos points at a name immediately after
	* ent->name in the cache. Does it expect
	* ent->name to be a directory?
	*/
	len = ce_namelen(active_cache[pos]);
	if ((ent->len < len) &&
	!strncmp(active_cache[pos]->name,
	ent->name, ent->len) &&
	active_cache[pos]->name[ent->len] == '/')
	killed = 1;
	break;
	}
	if (0 <= cache_name_pos(ent->name, sp - ent->name)) {
	/* If any of the leading directories in
	* ent->name is registered in the cache,
	* ent->name will be killed.
	*/
	killed = 1;
	break;
	}
	}
	if (killed)
	show_dir_entry(tag_killed, dir->entries[i]);
	}
	}

	static void show_ce_entry(const char tag, struct cache_entry ce)
	{
	int len = prefix_len;
	int offset = prefix_offset;

	if (len >= ce_namelen(ce))
	die("git ls-files: internal error - cache entry not superset of prefix");

	if (!match_pathspec(pathspec, ce->name, ce_namelen(ce), len, ps_matched))
	return;

	if (tag && *tag && show_valid_bit &&
	(ce->ce_flags & CE_VALID)) {
	static char alttag[4];
	memcpy(alttag, tag, 3);
	if (isalpha(tag[0]))
	alttag[0] = tolower(tag[0]);
	else if (tag[0] == '?')
	alttag[0] = '!';
	else {
	alttag[0] = 'v';
	alttag[1] = tag[0];
	alttag[2] = ' ';
	alttag[3] = 0;
	}
	tag = alttag;
	}

	if (!show_stage) {
	fputs(tag, stdout);
	} else {
	printf("%s%06o %s %d\t",
	tag,
	ce->ce_mode,
	abbrev ? find_unique_abbrev(ce->sha1,abbrev)
	: sha1_to_hex(ce->sha1),
	ce_stage(ce));
	}
	write_name_quoted(ce->name + offset, stdout, line_terminator);
	}

	static void show_files(struct dir_struct dir, const char prefix)
	{
	int i;

	/* For cached/deleted files we don't need to even do the readdir */
	if (show_others \|\| show_killed) {
	const char path = ".", base = "";
	int baselen = prefix_len;

	if (baselen)
	path = base = prefix;
	read_directory(dir, path, base, baselen, pathspec);
	if (show_others)
	show_other_files(dir);
	if (show_killed)
	show_killed_files(dir);
	}
	if (show_cached \| show_stage) {
	for (i = 0; i < active_nr; i++) {
	struct cache_entry *ce = active_cache[i];
	int dtype = ce_to_dtype(ce);
	if (excluded(dir, ce->name, &dtype) !=
	!!(dir->flags & DIR_SHOW_IGNORED))
	continue;
	if (show_unmerged && !ce_stage(ce))
	continue;
	if (ce->ce_flags & CE_UPDATE)
	continue;
	show_ce_entry(ce_stage(ce) ? tag_unmerged : tag_cached, ce);
	}
	}
	if (show_deleted \| show_modified) {
	for (i = 0; i < active_nr; i++) {
	struct cache_entry *ce = active_cache[i];
	struct stat st;
	int err;
	int dtype = ce_to_dtype(ce);
	if (excluded(dir, ce->name, &dtype) !=
	!!(dir->flags & DIR_SHOW_IGNORED))
	continue;
	if (ce->ce_flags & CE_UPDATE)
	continue;
	err = lstat(ce->name, &st);
	if (show_deleted && err)
	show_ce_entry(tag_removed, ce);
	if (show_modified && ce_modified(ce, &st, 0))
	show_ce_entry(tag_modified, ce);
	}
	}
	}

	/*
	* Prune the index to only contain stuff starting with "prefix"
	*/
	static void prune_cache(const char *prefix)
	{
	int pos = cache_name_pos(prefix, prefix_len);
	unsigned int first, last;

	if (pos < 0)
	pos = -pos-1;
	memmove(active_cache, active_cache + pos,
	(active_nr - pos) * sizeof(struct cache_entry *));
	active_nr -= pos;
	first = 0;
	last = active_nr;
	while (last > first) {
	int next = (last + first) >> 1;
	struct cache_entry *ce = active_cache[next];
	if (!strncmp(ce->name, prefix, prefix_len)) {
	first = next+1;
	continue;
	}
	last = next;
	}
	active_nr = last;
	}

	static const char verify_pathspec(const char prefix)
	{
	const char *p, n, *prev;
	unsigned long max;

	prev = NULL;
	max = PATH_MAX;
	for (p = pathspec; (n = *p) != NULL; p++) {
	int i, len = 0;
	for (i = 0; i < max; i++) {
	char c = n[i];
	if (prev && prev[i] != c)
	break;
	if (!c \|\| c == '*' \|\| c == '?')
	break;
	if (c == '/')
	len = i+1;
	}
	prev = n;
	if (len < max) {
	max = len;
	if (!max)
	break;
	}
	}

	if (prefix_offset > max \|\| memcmp(prev, prefix, prefix_offset))
	die("git ls-files: cannot generate relative filenames containing '..'");

	prefix_len = max;
	return max ? xmemdupz(prev, max) : NULL;
	}

	static void strip_trailing_slash_from_submodules(void)
	{
	const char **p;

	for (p = pathspec; *p != NULL; p++) {
	int len = strlen(*p), pos;

	if (len < 1 \|\| (*p)[len - 1] != '/')
	continue;
	pos = cache_name_pos(*p, len - 1);
	if (pos >= 0 && S_ISGITLINK(active_cache[pos]->ce_mode))
	p = xstrndup(p, len - 1);
	}
	}

	/*
	* Read the tree specified with --with-tree option
	* (typically, HEAD) into stage #1 and then
	* squash them down to stage #0. This is used for
	* --error-unmatch to list and check the path patterns
	* that were given from the command line. We are not
	* going to write this index out.
	*/
	void overlay_tree_on_cache(const char tree_name, const char prefix)
	{
	struct tree *tree;
	unsigned char sha1[20];
	const char **match;
	struct cache_entry *last_stage0 = NULL;
	int i;

	if (get_sha1(tree_name, sha1))
	die("tree-ish %s not found.", tree_name);
	tree = parse_tree_indirect(sha1);
	if (!tree)
	die("bad tree-ish %s", tree_name);

	/* Hoist the unmerged entries up to stage #3 to make room */
	for (i = 0; i < active_nr; i++) {
	struct cache_entry *ce = active_cache[i];
	if (!ce_stage(ce))
	continue;
	ce->ce_flags \|= CE_STAGEMASK;
	}

	if (prefix) {
	static const char *(matchbuf[2]);
	matchbuf[0] = prefix;
	matchbuf[1] = NULL;
	match = matchbuf;
	} else
	match = NULL;
	if (read_tree(tree, 1, match))
	die("unable to read tree entries %s", tree_name);

	for (i = 0; i < active_nr; i++) {
	struct cache_entry *ce = active_cache[i];
	switch (ce_stage(ce)) {
	case 0:
	last_stage0 = ce;
	/* fallthru */
	default:
	continue;
	case 1:
	/*
	* If there is stage #0 entry for this, we do not
	* need to show it. We use CE_UPDATE bit to mark
	* such an entry.
	*/
	if (last_stage0 &&
	!strcmp(last_stage0->name, ce->name))
	ce->ce_flags \|= CE_UPDATE;
	}
	}
	}

	int report_path_error(const char ps_matched, const char *pathspec, int prefix_offset)
	{
	/*
	* Make sure all pathspec matched; otherwise it is an error.
	*/
	int num, errors = 0;
	for (num = 0; pathspec[num]; num++) {
	int other, found_dup;

	if (ps_matched[num])
	continue;
	/*
	* The caller might have fed identical pathspec
	* twice. Do not barf on such a mistake.
	*/
	for (found_dup = other = 0;
	!found_dup && pathspec[other];
	other++) {
	if (other == num \|\| !ps_matched[other])
	continue;
	if (!strcmp(pathspec[other], pathspec[num]))
	/*
	* Ok, we have a match already.
	*/
	found_dup = 1;
	}
	if (found_dup)
	continue;

	error("pathspec '%s' did not match any file(s) known to git.",
	pathspec[num] + prefix_offset);
	errors++;
	}
	return errors;
	}

	static const char * const ls_files_usage[] = {
	"git ls-files [options] [<file>]*",
	NULL
	};

	static int option_parse_z(const struct option *opt,
	const char *arg, int unset)
	{
	line_terminator = unset ? '\n' : '\0';

	return 0;
	}

	static int option_parse_exclude(const struct option *opt,
	const char *arg, int unset)
	{
	struct exclude_list *list = opt->value;

	exc_given = 1;
	add_exclude(arg, "", 0, list);

	return 0;
	}

	static int option_parse_exclude_from(const struct option *opt,
	const char *arg, int unset)
	{
	struct dir_struct *dir = opt->value;

	exc_given = 1;
	add_excludes_from_file(dir, arg);

	return 0;
	}

	static int option_parse_exclude_standard(const struct option *opt,
	const char *arg, int unset)
	{
	struct dir_struct *dir = opt->value;

	exc_given = 1;
	setup_standard_excludes(dir);

	return 0;
	}

	int cmd_ls_files(int argc, const char *argv, const char prefix)
	{
	int require_work_tree = 0, show_tag = 0;
	struct dir_struct dir;
	struct option builtin_ls_files_options[] = {
	{ OPTION_CALLBACK, 'z', NULL, NULL, NULL,
	"paths are separated with NUL character",
	PARSE_OPT_NOARG, option_parse_z },
	OPT_BOOLEAN('t', NULL, &show_tag,
	"identify the file status with tags"),
	OPT_BOOLEAN('v', NULL, &show_valid_bit,
	"use lowercase letters for 'assume unchanged' files"),
	OPT_BOOLEAN('c', "cached", &show_cached,
	"show cached files in the output (default)"),
	OPT_BOOLEAN('d', "deleted", &show_deleted,
	"show deleted files in the output"),
	OPT_BOOLEAN('m', "modified", &show_modified,
	"show modified files in the output"),
	OPT_BOOLEAN('o', "others", &show_others,
	"show other files in the output"),
	OPT_BIT('i', "ignored", &dir.flags,
	"show ignored files in the output",
	DIR_SHOW_IGNORED),
	OPT_BOOLEAN('s', "stage", &show_stage,
	"show staged contents' object name in the output"),
	OPT_BOOLEAN('k', "killed", &show_killed,
	"show files on the filesystem that need to be removed"),
	OPT_BIT(0, "directory", &dir.flags,
	"show 'other' directories' name only",
	DIR_SHOW_OTHER_DIRECTORIES),
	OPT_BIT(0, "no-empty-directory", &dir.flags,
	"don't show empty directories",
	DIR_HIDE_EMPTY_DIRECTORIES),
	OPT_BOOLEAN('u', "unmerged", &show_unmerged,
	"show unmerged files in the output"),
	{ OPTION_CALLBACK, 'x', "exclude", &dir.exclude_list[EXC_CMDL], "pattern",
	"skip files matching pattern",
	0, option_parse_exclude },
	{ OPTION_CALLBACK, 'X', "exclude-from", &dir, "file",
	"exclude patterns are read from <file>",
	0, option_parse_exclude_from },
	OPT_STRING(0, "exclude-per-directory", &dir.exclude_per_dir, "file",
	"read additional per-directory exclude patterns in <file>"),
	{ OPTION_CALLBACK, 0, "exclude-standard", &dir, NULL,
	"add the standard git exclusions",
	PARSE_OPT_NOARG, option_parse_exclude_standard },
	{ OPTION_SET_INT, 0, "full-name", &prefix_offset, NULL,
	"make the output relative to the project top directory",
	PARSE_OPT_NOARG \| PARSE_OPT_NONEG, NULL },
	OPT_BOOLEAN(0, "error-unmatch", &error_unmatch,
	"if any <file> is not in the index, treat this as an error"),
	OPT_STRING(0, "with-tree", &with_tree, "tree-ish",
	"pretend that paths removed since <tree-ish> are still present"),
	OPT__ABBREV(&abbrev),
	OPT_END()
	};

	memset(&dir, 0, sizeof(dir));
	if (prefix)
	prefix_offset = strlen(prefix);
	git_config(git_default_config, NULL);

	argc = parse_options(argc, argv, builtin_ls_files_options,
	ls_files_usage, 0);
	if (show_tag \|\| show_valid_bit) {
	tag_cached = "H ";
	tag_unmerged = "M ";
	tag_removed = "R ";
	tag_modified = "C ";
	tag_other = "? ";
	tag_killed = "K ";
	}
	if (show_modified \|\| show_others \|\| show_deleted \|\| (dir.flags & DIR_SHOW_IGNORED) \|\| show_killed)
	require_work_tree = 1;
	if (show_unmerged)
	/*
	* There's no point in showing unmerged unless
	* you also show the stage information.
	*/
	show_stage = 1;
	if (dir.exclude_per_dir)
	exc_given = 1;

	if (require_work_tree && !is_inside_work_tree())
	setup_work_tree();

	pathspec = get_pathspec(prefix, argv);

	/* be nice with submodule paths ending in a slash */
	read_cache();
	if (pathspec)
	strip_trailing_slash_from_submodules();

	/* Verify that the pathspec matches the prefix */
	if (pathspec)
	prefix = verify_pathspec(prefix);

	/* Treat unmatching pathspec elements as errors */
	if (pathspec && error_unmatch) {
	int num;
	for (num = 0; pathspec[num]; num++)
	;
	ps_matched = xcalloc(1, num);
	}

	if ((dir.flags & DIR_SHOW_IGNORED) && !exc_given) {
	fprintf(stderr, "%s: --ignored needs some exclude pattern\n",
	argv[0]);
	exit(1);
	}

	/* With no flags, we default to showing the cached files */
	if (!(show_stage \| show_deleted \| show_others \| show_unmerged \|
	show_killed \| show_modified))
	show_cached = 1;

	if (prefix)
	prune_cache(prefix);
	if (with_tree) {
	/*
	* Basic sanity check; show-stages and show-unmerged
	* would not make any sense with this option.
	*/
	if (show_stage \|\| show_unmerged)
	die("ls-files --with-tree is incompatible with -s or -u");
	overlay_tree_on_cache(with_tree, prefix);
	}
	show_files(&dir, prefix);

	if (ps_matched) {
	int bad;
	bad = report_path_error(ps_matched, pathspec, prefix_offset);
	if (bad)
	fprintf(stderr, "Did you forget to 'git add'?\n");

	return bad ? 1 : 0;
	}

	return 0;
	}