Merge branch 'jk/prefix-filename'

Code clean-up with minor bugfixes.

* jk/prefix-filename:
  bundle: use prefix_filename with bundle path
  prefix_filename: simplify windows #ifdef
  prefix_filename: return newly allocated string
  prefix_filename: drop length parameter
  prefix_filename: move docstring to header file
  hash-object: fix buffer reuse with --path in a subdirectory

17 files changed, 86 insertions, 75 deletions

diff --git a/abspath.c b/abspath.c
index b02e068aa..7f1cfe979 100644
--- a/abspath.c
+++ b/abspath.c
@@ -246,29 +246,21 @@ char *absolute_pathdup(const char *path)
 	return strbuf_detach(&sb, NULL);
 }
 
-/*
- * Unlike prefix_path, this should be used if the named file does
- * not have to interact with index entry; i.e. name of a random file
- * on the filesystem.
- */
-const char *prefix_filename(const char *pfx, int pfx_len, const char *arg)
+char *prefix_filename(const char *pfx, const char *arg)
 {
-	static struct strbuf path = STRBUF_INIT;
-#ifndef GIT_WINDOWS_NATIVE
-	if (!pfx_len || is_absolute_path(arg))
-		return arg;
-	strbuf_reset(&path);
-	strbuf_add(&path, pfx, pfx_len);
-	strbuf_addstr(&path, arg);
-#else
-	/* don't add prefix to absolute paths, but still replace '\' by '/' */
-	strbuf_reset(&path);
-	if (is_absolute_path(arg))
+	struct strbuf path = STRBUF_INIT;
+	size_t pfx_len = pfx ? strlen(pfx) : 0;
+
+	if (!pfx_len)
+		; /* nothing to prefix */
+	else if (is_absolute_path(arg))
 		pfx_len = 0;
-	else if (pfx_len)
+	else
 		strbuf_add(&path, pfx, pfx_len);
+
 	strbuf_addstr(&path, arg);
+#ifdef GIT_WINDOWS_NATIVE
 	convert_slashes(path.buf + pfx_len);
 #endif
-	return path.buf;
+	return strbuf_detach(&path, NULL);
 }
diff --git a/apply.c b/apply.c
index 0e2caeab9..e6dbab26a 100644
--- a/apply.c
+++ b/apply.c
@@ -2046,7 +2046,7 @@ static void prefix_one(struct apply_state *state, char **name)
 	char *old_name = *name;
 	if (!old_name)
 		return;
-	*name = xstrdup(prefix_filename(state->prefix, state->prefix_length, *name));
+	*name = prefix_filename(state->prefix, *name);
 	free(old_name);
 }
 
@@ -4805,6 +4805,7 @@ int apply_all_patches(struct apply_state *state,
 
 	for (i = 0; i < argc; i++) {
 		const char *arg = argv[i];
+		char *to_free = NULL;
 		int fd;
 
 		if (!strcmp(arg, "-")) {
@@ -4814,21 +4815,21 @@ int apply_all_patches(struct apply_state *state,
 			errs |= res;
 			read_stdin = 0;
 			continue;
-		} else if (0 < state->prefix_length)
-			arg = prefix_filename(state->prefix,
-					      state->prefix_length,
-					      arg);
+		} else
+			arg = to_free = prefix_filename(state->prefix, arg);
 
 		fd = open(arg, O_RDONLY);
 		if (fd < 0) {
 			error(_("can't open patch '%s': %s"), arg, strerror(errno));
 			res = -128;
+			free(to_free);
 			goto end;
 		}
 		read_stdin = 0;
 		set_default_whitespace_mode(state);
 		res = apply_patch(state, fd, arg, options);
 		close(fd);
+		free(to_free);
 		if (res < 0)
 			goto end;
 		errs |= res;
diff --git a/builtin/bundle.c b/builtin/bundle.c
index 4883a435a..d0de59b94 100644
--- a/builtin/bundle.c
+++ b/builtin/bundle.c
@@ -20,21 +20,15 @@ int cmd_bundle(int argc, const char **argv, const char *prefix)
 	struct bundle_header header;
 	const char *cmd, *bundle_file;
 	int bundle_fd = -1;
-	char buffer[PATH_MAX];
 
 	if (argc < 3)
 		usage(builtin_bundle_usage);
 
 	cmd = argv[1];
-	bundle_file = argv[2];
+	bundle_file = prefix_filename(prefix, argv[2]);
 	argc -= 2;
 	argv += 2;
 
-	if (prefix && bundle_file[0] != '/') {
-		snprintf(buffer, sizeof(buffer), "%s/%s", prefix, bundle_file);
-		bundle_file = buffer;
-	}
-
 	memset(&header, 0, sizeof(header));
 	if (strcmp(cmd, "create") && (bundle_fd =
 				read_bundle_header(bundle_file, &header)) < 0)
diff --git a/builtin/config.c b/builtin/config.c
index 05843a0f9..4f49a0edb 100644
--- a/builtin/config.c
+++ b/builtin/config.c
@@ -527,9 +527,7 @@ int cmd_config(int argc, const char **argv, const char *prefix)
 	else if (given_config_source.file) {
 		if (!is_absolute_path(given_config_source.file) && prefix)
 			given_config_source.file =
-				xstrdup(prefix_filename(prefix,
-							strlen(prefix),
-							given_config_source.file));
+				prefix_filename(prefix, given_config_source.file);
 	}
 
 	if (respect_includes == -1)
diff --git a/builtin/hash-object.c b/builtin/hash-object.c
index 9028e1fdc..bbeaf20bc 100644
--- a/builtin/hash-object.c
+++ b/builtin/hash-object.c
@@ -102,7 +102,6 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 		OPT_END()
 	};
 	int i;
-	int prefix_length = -1;
 	const char *errstr = NULL;
 
 	argc = parse_options(argc, argv, NULL, hash_object_options,
@@ -113,9 +112,8 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 	else
 		prefix = setup_git_directory_gently(&nongit);
 
-	prefix_length = prefix ? strlen(prefix) : 0;
 	if (vpath && prefix)
-		vpath = prefix_filename(prefix, prefix_length, vpath);
+		vpath = xstrdup(prefix_filename(prefix, vpath));
 
 	git_config(git_default_config, NULL);
 
@@ -144,11 +142,13 @@ int cmd_hash_object(int argc, const char **argv, const char *prefix)
 
 	for (i = 0 ; i < argc; i++) {
 		const char *arg = argv[i];
+		char *to_free = NULL;
 
-		if (0 <= prefix_length)
-			arg = prefix_filename(prefix, prefix_length, arg);
+		if (prefix)
+			arg = to_free = prefix_filename(prefix, arg);
 		hash_object(arg, type, no_filters ? NULL : vpath ? vpath : arg,
 			    flags, literally);
+		free(to_free);
 	}
 
 	if (stdin_paths)
diff --git a/builtin/log.c b/builtin/log.c
index 281af8c1e..670229cbb 100644
--- a/builtin/log.c
+++ b/builtin/log.c
@@ -1084,8 +1084,7 @@ static const char *set_outdir(const char *prefix, const char *output_directory)
 	if (!output_directory)
 		return prefix;
 
-	return xstrdup(prefix_filename(prefix, outdir_offset,
-				       output_directory));
+	return prefix_filename(prefix, output_directory);
 }
 
 static const char * const builtin_format_patch_usage[] = {
diff --git a/builtin/mailinfo.c b/builtin/mailinfo.c
index e3b62f2fc..cfb667a59 100644
--- a/builtin/mailinfo.c
+++ b/builtin/mailinfo.c
@@ -11,13 +11,6 @@
 static const char mailinfo_usage[] =
 	"git mailinfo [-k | -b] [-m | --message-id] [-u | --encoding=<encoding> | -n] [--scissors | --no-scissors] <msg> <patch> < mail >info";
 
-static char *prefix_copy(const char *prefix, const char *filename)
-{
-	if (!prefix || is_absolute_path(filename))
-		return xstrdup(filename);
-	return xstrdup(prefix_filename(prefix, strlen(prefix), filename));
-}
-
 int cmd_mailinfo(int argc, const char **argv, const char *prefix)
 {
 	const char *def_charset;
@@ -60,8 +53,8 @@ int cmd_mailinfo(int argc, const char **argv, const char *prefix)
 	mi.input = stdin;
 	mi.output = stdout;
 
-	msgfile = prefix_copy(prefix, argv[1]);
-	patchfile = prefix_copy(prefix, argv[2]);
+	msgfile = prefix_filename(prefix, argv[1]);
+	patchfile = prefix_filename(prefix, argv[2]);
 
 	status = !!mailinfo(&mi, msgfile, patchfile);
 	clear_mailinfo(&mi);
diff --git a/builtin/merge-file.c b/builtin/merge-file.c
index 13e22a2f0..47dde7c39 100644
--- a/builtin/merge-file.c
+++ b/builtin/merge-file.c
@@ -28,7 +28,6 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 	xmparam_t xmp = {{0}};
 	int ret = 0, i = 0, to_stdout = 0;
 	int quiet = 0;
-	int prefixlen = 0;
 	struct option options[] = {
 		OPT_BOOL('p', "stdout", &to_stdout, N_("send results to standard output")),
 		OPT_SET_INT(0, "diff3", &xmp.style, N_("use a diff3 based merge"), XDL_MERGE_DIFF3),
@@ -65,15 +64,19 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 			return error_errno("failed to redirect stderr to /dev/null");
 	}
 
-	if (prefix)
-		prefixlen = strlen(prefix);
-
 	for (i = 0; i < 3; i++) {
-		const char *fname = prefix_filename(prefix, prefixlen, argv[i]);
+		char *fname;
+		int ret;
+
 		if (!names[i])
 			names[i] = argv[i];
-		if (read_mmfile(mmfs + i, fname))
+
+		fname = prefix_filename(prefix, argv[i]);
+		ret = read_mmfile(mmfs + i, fname);
+		free(fname);
+		if (ret)
 			return -1;
+
 		if (mmfs[i].size > MAX_XDIFF_SIZE ||
 		    buffer_is_binary(mmfs[i].ptr, mmfs[i].size))
 			return error("Cannot merge binary files: %s",
@@ -90,7 +93,7 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 
 	if (ret >= 0) {
 		const char *filename = argv[0];
-		const char *fpath = prefix_filename(prefix, prefixlen, argv[0]);
+		char *fpath = prefix_filename(prefix, argv[0]);
 		FILE *f = to_stdout ? stdout : fopen(fpath, "wb");
 
 		if (!f)
@@ -102,6 +105,7 @@ int cmd_merge_file(int argc, const char **argv, const char *prefix)
 		else if (fclose(f))
 			ret = error_errno("Could not close %s", filename);
 		free(result.ptr);
+		free(fpath);
 	}
 
 	if (ret > 127)
diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
index 1e5bdea0d..9e53a1a7c 100644
--- a/builtin/rev-parse.c
+++ b/builtin/rev-parse.c
@@ -228,9 +228,9 @@ static int show_file(const char *arg, int output_prefix)
 	if ((filter & (DO_NONFLAGS|DO_NOREV)) == (DO_NONFLAGS|DO_NOREV)) {
 		if (output_prefix) {
 			const char *prefix = startup_info->prefix;
-			show(prefix_filename(prefix,
-					     prefix ? strlen(prefix) : 0,
-					     arg));
+			char *fname = prefix_filename(prefix, arg);
+			show(fname);
+			free(fname);
 		} else
 			show(arg);
 		return 1;
diff --git a/builtin/worktree.c b/builtin/worktree.c
index 831fe058a..9993ded41 100644
--- a/builtin/worktree.c
+++ b/builtin/worktree.c
@@ -318,7 +318,8 @@ static int add(int ac, const char **av, const char *prefix)
 {
 	struct add_opts opts;
 	const char *new_branch_force = NULL;
-	const char *path, *branch;
+	char *path;
+	const char *branch;
 	struct option options[] = {
 		OPT__FORCE(&opts.force, N_("checkout <branch> even if already checked out in other worktree")),
 		OPT_STRING('b', NULL, &opts.new_branch, N_("branch"),
@@ -338,7 +339,7 @@ static int add(int ac, const char **av, const char *prefix)
 	if (ac < 1 || ac > 2)
 		usage_with_options(worktree_usage, options);
 
-	path = prefix_filename(prefix, strlen(prefix), av[0]);
+	path = prefix_filename(prefix, av[0]);
 	branch = ac < 2 ? "HEAD" : av[1];
 
 	if (!strcmp(branch, "-"))
diff --git a/cache.h b/cache.h
index 2214d52f6..db4120c23 100644
--- a/cache.h
+++ b/cache.h
@@ -529,7 +529,19 @@ extern const char *setup_git_directory_gently(int *);
 extern const char *setup_git_directory(void);
 extern char *prefix_path(const char *prefix, int len, const char *path);
 extern char *prefix_path_gently(const char *prefix, int len, int *remaining, const char *path);
-extern const char *prefix_filename(const char *prefix, int len, const char *path);
+
+/*
+ * Concatenate "prefix" (if len is non-zero) and "path", with no
+ * connecting characters (so "prefix" should end with a "/").
+ * Unlike prefix_path, this should be used if the named file does
+ * not have to interact with index entry; i.e. name of a random file
+ * on the filesystem.
+ *
+ * The return value is always a newly allocated string (even if the
+ * prefix was empty).
+ */
+extern char *prefix_filename(const char *prefix, const char *path);
+
 extern int check_filename(const char *prefix, const char *name);
 extern void verify_filename(const char *prefix,
 			    const char *name,
diff --git a/diff-no-index.c b/diff-no-index.c
index df762fd0f..79229382b 100644
--- a/diff-no-index.c
+++ b/diff-no-index.c
@@ -236,7 +236,7 @@ static void fixup_paths(const char **path, struct strbuf *replacement)
 void diff_no_index(struct rev_info *revs,
 		   int argc, const char **argv)
 {
-	int i, prefixlen;
+	int i;
 	const char *paths[2];
 	struct strbuf replacement = STRBUF_INIT;
 	const char *prefix = revs->prefix;
@@ -257,7 +257,6 @@ void diff_no_index(struct rev_info *revs,
 		}
 	}
 
-	prefixlen = prefix ? strlen(prefix) : 0;
 	for (i = 0; i < 2; i++) {
 		const char *p = argv[argc - 2 + i];
 		if (!strcmp(p, "-"))
@@ -266,8 +265,8 @@ void diff_no_index(struct rev_info *revs,
 			 * path that is "-", spell it as "./-".
 			 */
 			p = file_from_standard_input;
-		else if (prefixlen)
-			p = xstrdup(prefix_filename(prefix, prefixlen, p));
+		else if (prefix)
+			p = prefix_filename(prefix, p);
 		paths[i] = p;
 	}
 
diff --git a/diff.c b/diff.c
index a628ac3a9..58cb72d7e 100644
--- a/diff.c
+++ b/diff.c
@@ -4023,8 +4023,7 @@ int diff_opt_parse(struct diff_options *options,
 	else if (!strcmp(arg, "--pickaxe-regex"))
 		options->pickaxe_opts |= DIFF_PICKAXE_REGEX;
 	else if ((argcount = short_opt('O', av, &optarg))) {
-		const char *path = prefix_filename(prefix, strlen(prefix), optarg);
-		options->orderfile = xstrdup(path);
+		options->orderfile = prefix_filename(prefix, optarg);
 		return argcount;
 	}
 	else if ((argcount = parse_long_opt("diff-filter", av, &optarg))) {
@@ -4071,13 +4070,14 @@ int diff_opt_parse(struct diff_options *options,
 	else if (!strcmp(arg, "--no-function-context"))
 		DIFF_OPT_CLR(options, FUNCCONTEXT);
 	else if ((argcount = parse_long_opt("output", av, &optarg))) {
-		const char *path = prefix_filename(prefix, strlen(prefix), optarg);
+		char *path = prefix_filename(prefix, optarg);
 		options->file = fopen(path, "w");
 		if (!options->file)
 			die_errno("Could not open '%s'", path);
 		options->close_file = 1;
 		if (options->use_color != GIT_COLOR_ALWAYS)
 			options->use_color = GIT_COLOR_NEVER;
+		free(path);
 		return argcount;
 	} else
 		return 0;
diff --git a/parse-options.c b/parse-options.c
index 4fbe924a5..a23a1e67f 100644
--- a/parse-options.c
+++ b/parse-options.c
@@ -40,7 +40,7 @@ static void fix_filename(const char *prefix, const char **file)
 	if (!file || !*file || !prefix || is_absolute_path(*file)
 	    || !strcmp("-", *file))
 		return;
-	*file = xstrdup(prefix_filename(prefix, strlen(prefix), *file));
+	*file = prefix_filename(prefix, *file);
 }
 
 static int opt_command_mode_error(const struct option *opt,
diff --git a/setup.c b/setup.c
index 64f922a93..5c7946d2b 100644
--- a/setup.c
+++ b/setup.c
@@ -135,6 +135,7 @@ int path_inside_repo(const char *prefix, const char *path)
 int check_filename(const char *prefix, const char *arg)
 {
 	const char *name;
+	char *to_free = NULL;
 	struct stat st;
 
 	if (starts_with(arg, ":/")) {
@@ -142,13 +143,17 @@ int check_filename(const char *prefix, const char *arg)
 			return 1;
 		name = arg + 2;
 	} else if (prefix)
-		name = prefix_filename(prefix, strlen(prefix), arg);
+		name = to_free = prefix_filename(prefix, arg);
 	else
 		name = arg;
-	if (!lstat(name, &st))
+	if (!lstat(name, &st)) {
+		free(to_free);
 		return 1; /* file exists */
-	if (errno == ENOENT || errno == ENOTDIR)
+	}
+	if (errno == ENOENT || errno == ENOTDIR) {
+		free(to_free);
 		return 0; /* file does not exist */
+	}
 	die_errno("failed to stat '%s'", arg);
 }
 
diff --git a/t/t1007-hash-object.sh b/t/t1007-hash-object.sh
index c5245c5cb..532682f51 100755
--- a/t/t1007-hash-object.sh
+++ b/t/t1007-hash-object.sh
@@ -134,6 +134,16 @@ test_expect_success 'gitattributes also work in a subdirectory' '
 	)
 '
 
+test_expect_success '--path works in a subdirectory' '
+	(
+		cd subdir &&
+		path1_sha=$(git hash-object --path=../file1 ../file0) &&
+		path0_sha=$(git hash-object --path=../file0 ../file1) &&
+		test "$file0_sha" = "$path0_sha" &&
+		test "$file1_sha" = "$path1_sha"
+	)
+'
+
 test_expect_success 'check that --no-filters option works' '
 	nofilters_file1=$(git hash-object --no-filters file1) &&
 	test "$file0_sha" = "$nofilters_file1" &&
diff --git a/worktree.c b/worktree.c
index fa7bc67a5..bae787cf8 100644
--- a/worktree.c
+++ b/worktree.c
@@ -250,16 +250,19 @@ struct worktree *find_worktree(struct worktree **list,
 {
 	struct worktree *wt;
 	char *path;
+	char *to_free = NULL;
 
 	if ((wt = find_worktree_by_suffix(list, arg)))
 		return wt;
 
-	arg = prefix_filename(prefix, strlen(prefix), arg);
+	if (prefix)
+		arg = to_free = prefix_filename(prefix, arg);
 	path = real_pathdup(arg, 1);
 	for (; *list; list++)
 		if (!fspathcmp(path, real_path((*list)->path)))
 			break;
 	free(path);
+	free(to_free);
 	return *list;
 }