thodg/libgit2

diff --git a/include/git2/config.h b/include/git2/config.h
index 36946c4..c46e7fc 100644
--- a/include/git2/config.h
+++ b/include/git2/config.h
@@ -33,7 +33,7 @@ struct git_config_file {
 	int (*set)(struct git_config_file *, const char *key, const char *value);
 	int (*set_multivar)(git_config_file *cfg, const char *name, const char *regexp, const char *value);
 	int (*del)(struct git_config_file *, const char *key);
-	int (*foreach)(struct git_config_file *, int (*fn)(const char *, const char *, void *), void *data);
+	int (*foreach)(struct git_config_file *, const char *, int (*fn)(const char *, const char *, void *), void *data);
 	void (*free)(struct git_config_file *);
 };
 
@@ -314,6 +314,24 @@ GIT_EXTERN(int) git_config_foreach(
 	int (*callback)(const char *var_name, const char *value, void *payload),
 	void *payload);
 
+/**
+ * Perform an operation on each config variable matching a regular expression.
+ *
+ * This behaviors like `git_config_foreach` with an additional filter of a
+ * regular expression that filters which config keys are passed to the
+ * callback.
+ *
+ * @param cfg where to get the variables from
+ * @param regexp regular expression to match against config names
+ * @param callback the function to call on each variable
+ * @param payload the data to pass to the callback
+ * @return 0 or the return value of the callback which didn't return 0
+ */
+GIT_EXTERN(int) git_config_foreach_match(
+	git_config *cfg,
+	const char *regexp,
+	int (*callback)(const char *var_name, const char *value, void *payload),
+	void *payload);
 
 /**
  * Query the value of a config variable and return it mapped to
diff --git a/include/git2/repository.h b/include/git2/repository.h
index 0b56a08..ff81b75 100644
--- a/include/git2/repository.h
+++ b/include/git2/repository.h
@@ -194,9 +194,12 @@ GIT_EXTERN(const char *) git_repository_workdir(git_repository *repo);
  *
  * @param repo A repository object
  * @param workdir The path to a working directory
+ * @param update_gitlink Create/update gitlink in workdir and set config
+ *        "core.worktree" (if workdir is not the parent of the .git directory)
  * @return 0, or an error code
  */
-GIT_EXTERN(int) git_repository_set_workdir(git_repository *repo, const char *workdir);
+GIT_EXTERN(int) git_repository_set_workdir(
+	git_repository *repo, const char *workdir, int update_gitlink);
 
 /**
  * Check if a repository is bare
diff --git a/src/buffer.c b/src/buffer.c
index 04aaec3..5d54ee1 100644
--- a/src/buffer.c
+++ b/src/buffer.c
@@ -141,6 +141,42 @@ int git_buf_puts(git_buf *buf, const char *string)
 	return git_buf_put(buf, string, strlen(string));
 }
 
+int git_buf_puts_escaped(
+	git_buf *buf, const char *string, const char *esc_chars, const char *esc_with)
+{
+	const char *scan = string;
+	size_t total = 0, esc_with_len = strlen(esc_with);
+
+	while (*scan) {
+		size_t count = strcspn(scan, esc_chars);
+		total += count + 1 + esc_with_len;
+		scan += count + 1;
+	}
+
+	ENSURE_SIZE(buf, buf->size + total + 1);
+
+	for (scan = string; *scan; ) {
+		size_t count = strcspn(scan, esc_chars);
+
+		memmove(buf->ptr + buf->size, scan, count);
+		scan += count;
+		buf->size += count;
+
+		if (*scan) {
+			memmove(buf->ptr + buf->size, esc_with, esc_with_len);
+			buf->size += esc_with_len;
+
+			memmove(buf->ptr + buf->size, scan, 1);
+			scan += 1;
+			buf->size += 1;
+		}
+	}
+
+	buf->ptr[buf->size] = '\0';
+
+	return 0;
+}
+
 int git_buf_vprintf(git_buf *buf, const char *format, va_list ap)
 {
 	int len;
diff --git a/src/buffer.h b/src/buffer.h
index 50c75f6..75f3b0e 100644
--- a/src/buffer.h
+++ b/src/buffer.h
@@ -91,6 +91,18 @@ int git_buf_join_n(git_buf *buf, char separator, int nbuf, ...);
 int git_buf_join(git_buf *buf, char separator, const char *str_a, const char *str_b);
 
 /**
+ * Copy string into buf prefixing every character that is contained in the
+ * esc_chars string with the esc_with string.
+ */
+int git_buf_puts_escaped(
+	git_buf *buf, const char *string, const char *esc_chars, const char *esc_with);
+
+GIT_INLINE(int) git_buf_puts_escape_regex(git_buf *buf, const char *string)
+{
+	return git_buf_puts_escaped(buf, string, "^.[]$()|*+?{}\\", "\\");
+}
+
+/**
  * Join two strings as paths, inserting a slash between as needed.
  * @return 0 on success, -1 on failure
  */
@@ -121,6 +133,13 @@ GIT_INLINE(ssize_t) git_buf_rfind_next(git_buf *buf, char ch)
 	return idx;
 }
 
+GIT_INLINE(ssize_t) git_buf_rfind(git_buf *buf, char ch)
+{
+	ssize_t idx = (ssize_t)buf->size - 1;
+	while (idx >= 0 && buf->ptr[idx] != ch) idx--;
+	return idx;
+}
+
 /* Remove whitespace from the end of the buffer */
 void git_buf_rtrim(git_buf *buf);
 
diff --git a/src/config.c b/src/config.c
index d18b85c..98fb3b2 100644
--- a/src/config.c
+++ b/src/config.c
@@ -136,17 +136,27 @@ int git_config_add_file(git_config *cfg, git_config_file *file, int priority)
  * Loop over all the variables
  */
 
-int git_config_foreach(git_config *cfg, int (*fn)(const char *, const char *, void *), void *data)
+int git_config_foreach(
+	git_config *cfg, int (*fn)(const char *, const char *, void *), void *data)
+{
+	return git_config_foreach_match(cfg, NULL, fn, data);
+}
+
+int git_config_foreach_match(
+	git_config *cfg,
+	const char *regexp,
+	int (*fn)(const char *, const char *, void *),
+	void *data)
 {
 	int ret = 0;
 	unsigned int i;
 	file_internal *internal;
 	git_config_file *file;
 
-	for(i = 0; i < cfg->files.length && ret == 0; ++i) {
+	for (i = 0; i < cfg->files.length && ret == 0; ++i) {
 		internal = git_vector_get(&cfg->files, i);
 		file = internal->file;
-		ret = file->foreach(file, fn, data);
+		ret = file->foreach(file, regexp, fn, data);
 	}
 
 	return ret;
diff --git a/src/config_file.c b/src/config_file.c
index fd1aa8d..1f3ebfc 100644
--- a/src/config_file.c
+++ b/src/config_file.c
@@ -188,25 +188,46 @@ static void backend_free(git_config_file *_backend)
 	git__free(backend);
 }
 
-static int file_foreach(git_config_file *backend, int (*fn)(const char *, const char *, void *), void *data)
+static int file_foreach(
+	git_config_file *backend,
+	const char *regexp,
+	int (*fn)(const char *, const char *, void *),
+	void *data)
 {
 	diskfile_backend *b = (diskfile_backend *)backend;
 	cvar_t *var;
 	const char *key;
+	regex_t regex;
+	int result = 0;
 
 	if (!b->values)
 		return 0;
 
+	if (regexp != NULL) {
+		if ((result = regcomp(&regex, regexp, REG_EXTENDED)) < 0) {
+			giterr_set_regex(&regex, result);
+			regfree(&regex);
+			return -1;
+		}
+	}
+
 	git_strmap_foreach(b->values, key, var,
-		do {
-			if (fn(key, var->value, data) < 0)
-				break;
+		for (; var != NULL; var = CVAR_LIST_NEXT(var)) {
+			/* skip non-matching keys if regexp was provided */
+			if (regexp && regexec(&regex, key, 0, NULL, 0) != 0)
+				continue;
 
-			var = CVAR_LIST_NEXT(var);
-		} while (var != NULL);
+			/* abort iterator on non-zero return value */
+			if ((result = fn(key, var->value, data)) != 0)
+				goto cleanup;
+		}
 	);
 
-	return 0;
+cleanup:
+	if (regexp != NULL)
+		regfree(&regex);
+
+	return result;
 }
 
 static int config_set(git_config_file *cfg, const char *name, const char *value)
@@ -337,6 +358,7 @@ static int config_get_multivar(
 		result = regcomp(&regex, regex_str, REG_EXTENDED);
 		if (result < 0) {
 			giterr_set_regex(&regex, result);
+			regfree(&regex);
 			return -1;
 		}
 
@@ -396,6 +418,7 @@ static int config_set_multivar(
 	if (result < 0) {
 		git__free(key);
 		giterr_set_regex(&preg, result);
+		regfree(&preg);
 		return -1;
 	}
 
diff --git a/src/config_file.h b/src/config_file.h
index 0080b57..c312928 100644
--- a/src/config_file.h
+++ b/src/config_file.h
@@ -19,12 +19,27 @@ GIT_INLINE(void) git_config_file_free(git_config_file *cfg)
 	cfg->free(cfg);
 }
 
+GIT_INLINE(int) git_config_file_set_string(
+	git_config_file *cfg, const char *name, const char *value)
+{
+	return cfg->set(cfg, name, value);
+}
+
 GIT_INLINE(int) git_config_file_foreach(
 	git_config_file *cfg,
 	int (*fn)(const char *key, const char *value, void *data),
 	void *data)
 {
-	return cfg->foreach(cfg, fn, data);
+	return cfg->foreach(cfg, NULL, fn, data);
+}
+
+GIT_INLINE(int) git_config_file_foreach_match(
+	git_config_file *cfg,
+	const char *regexp,
+	int (*fn)(const char *key, const char *value, void *data),
+	void *data)
+{
+	return cfg->foreach(cfg, regexp, fn, data);
 }
 
 #endif
diff --git a/src/path.c b/src/path.c
index 9c88240..e9bc487 100644
--- a/src/path.c
+++ b/src/path.c
@@ -17,9 +17,7 @@
 #include <stdio.h>
 #include <ctype.h>
 
-#ifdef GIT_WIN32
 #define LOOKS_LIKE_DRIVE_PREFIX(S) (git__isalpha((S)[0]) && (S)[1] == ':')
-#endif
 
 /*
  * Based on the Android implementation, BSD licensed.
@@ -172,11 +170,11 @@ int git_path_root(const char *path)
 {
 	int offset = 0;
 
-#ifdef GIT_WIN32
 	/* Does the root of the path look like a windows drive ? */
 	if (LOOKS_LIKE_DRIVE_PREFIX(path))
 		offset += 2;
 
+#ifdef GIT_WIN32
 	/* Are we dealing with a windows network path? */
 	else if ((path[0] == '/' && path[1] == '/') ||
 		(path[0] == '\\' && path[1] == '\\'))
@@ -464,6 +462,71 @@ int git_path_find_dir(git_buf *dir, const char *path, const char *base)
 	return error;
 }
 
+int git_path_resolve_relative(git_buf *path, size_t ceiling)
+{
+	char *base, *to, *from, *next;
+	size_t len;
+
+	if (!path || git_buf_oom(path))
+		return -1;
+
+	if (ceiling > path->size)
+		ceiling = path->size;
+
+	/* recognize drive prefixes, etc. that should not be backed over */
+	if (ceiling == 0)
+		ceiling = git_path_root(path->ptr) + 1;
+
+	/* recognize URL prefixes that should not be backed over */
+	if (ceiling == 0) {
+		for (next = path->ptr; *next && git__isalpha(*next); ++next);
+		if (next[0] == ':' && next[1] == '/' && next[2] == '/')
+			ceiling = (next + 3) - path->ptr;
+	}
+
+	base = to = from = path->ptr + ceiling;
+
+	while (*from) {
+		for (next = from; *next && *next != '/'; ++next);
+
+		len = next - from;
+
+		if (len == 1 && from[0] == '.')
+			/* do nothing with singleton dot */;
+
+		else if (len == 2 && from[0] == '.' && from[1] == '.') {
+			while (to > base && to[-1] == '/') to--;
+			while (to > base && to[-1] != '/') to--;
+		}
+
+		else {
+			if (*next == '/')
+				len++;
+
+			if (to != from)
+				memmove(to, from, len);
+
+			to += len;
+		}
+
+		from += len;
+
+		while (*from == '/') from++;
+	}
+
+	*to = '\0';
+
+	path->size = to - path->ptr;
+
+	return 0;
+}
+
+int git_path_apply_relative(git_buf *target, const char *relpath)
+{
+	git_buf_joinpath(target, git_buf_cstr(target), relpath);
+	return git_path_resolve_relative(target, 0);
+}
+
 int git_path_cmp(
 	const char *name1, size_t len1, int isdir1,
 	const char *name2, size_t len2, int isdir2)
diff --git a/src/path.h b/src/path.h
index fd76805..d68393b 100644
--- a/src/path.h
+++ b/src/path.h
@@ -186,6 +186,29 @@ extern int git_path_prettify_dir(git_buf *path_out, const char *path, const char
 extern int git_path_find_dir(git_buf *dir, const char *path, const char *base);
 
 /**
+ * Resolve relative references within a path.
+ *
+ * This eliminates "./" and "../" relative references inside a path,
+ * as well as condensing multiple slashes into single ones.  It will
+ * not touch the path before the "ceiling" length.
+ *
+ * Additionally, this will recognize an "c:/" drive prefix or a "xyz://" URL
+ * prefix and not touch that part of the path.
+ */
+extern int git_path_resolve_relative(git_buf *path, size_t ceiling);
+
+/**
+ * Apply a relative path to base path.
+ *
+ * Note that the base path could be a filename or a URL and this
+ * should still work.  The relative path is walked segment by segment
+ * with three rules: series of slashes will be condensed to a single
+ * slash, "." will be eaten with no change, and ".." will remove a
+ * segment from the base path.
+ */
+extern int git_path_apply_relative(git_buf *target, const char *relpath);
+
+/**
  * Walk each directory entry, except '.' and '..', calling fn(state).
  *
  * @param pathbuf buffer the function reads the initial directory
diff --git a/src/repository.c b/src/repository.c
index bee7b3e..a293171 100644
--- a/src/repository.c
+++ b/src/repository.c
@@ -741,15 +741,24 @@ static int repo_init_config(const char *git_dir, bool is_bare, bool is_reinit)
 #define GIT_DESC_CONTENT "Unnamed repository; edit this file 'description' to name the repository.\n"
 
 static int repo_write_template(
-	const char *git_dir, const char *file, mode_t mode, const char *content)
+	const char *git_dir,
+	bool allow_overwrite,
+	const char *file,
+	mode_t mode,
+	const char *content)
 {
 	git_buf path = GIT_BUF_INIT;
-	int fd, error = 0;
+	int fd, error = 0, flags;
 
 	if (git_buf_joinpath(&path, git_dir, file) < 0)
 		return -1;
 
-	fd = p_open(git_buf_cstr(&path), O_WRONLY | O_CREAT | O_EXCL, mode);
+	if (allow_overwrite)
+		flags = O_WRONLY | O_CREAT | O_TRUNC;
+	else
+		flags = O_WRONLY | O_CREAT | O_EXCL;
+
+	fd = p_open(git_buf_cstr(&path), flags, mode);
 
 	if (fd >= 0) {
 		error = p_write(fd, content, strlen(content));
@@ -811,7 +820,7 @@ static int repo_init_structure(const char *git_dir, int is_bare)
 	/* Make template files as needed */
 	for (i = 0; tmpl[i].file != NULL; ++i) {
 		if (repo_write_template(
-				git_dir, tmpl[i].file, tmpl[i].mode, tmpl[i].content) < 0)
+				git_dir, false, tmpl[i].file, tmpl[i].mode, tmpl[i].content) < 0)
 			return -1;
 	}
 
@@ -943,8 +952,47 @@ const char *git_repository_workdir(git_repository *repo)
 	return repo->workdir;
 }
 
-int git_repository_set_workdir(git_repository *repo, const char *workdir)
+static int write_gitlink(
+	const char *in_dir, const char *to_repo)
+{
+	int error;
+	git_buf buf = GIT_BUF_INIT;
+	struct stat st;
+
+	if (git_path_dirname_r(&buf, to_repo) < 0 ||
+		git_path_to_dir(&buf) < 0)
+		return -1;
+
+	/* don't write gitlink to natural workdir */
+	if (git__suffixcmp(to_repo, "/" DOT_GIT "/") == 0 &&
+		strcmp(in_dir, buf.ptr) == 0)
+		return GIT_PASSTHROUGH;
+
+	if (git_buf_joinpath(&buf, in_dir, DOT_GIT) < 0)
+		return -1;
+
+	if (!p_stat(buf.ptr, &st) && !S_ISREG(st.st_mode)) {
+		giterr_set(GITERR_REPOSITORY,
+			"Cannot overwrite gitlink file into path '%s'", in_dir);
+		return GIT_EEXISTS;
+	}
+
+	git_buf_clear(&buf);
+
+	if (git_buf_printf(&buf, "%s %s", GIT_FILE_CONTENT_PREFIX, to_repo) < 0)
+		return -1;
+
+	error = repo_write_template(in_dir, true, DOT_GIT, 0644, buf.ptr);
+
+	git_buf_free(&buf);
+
+	return error;
+}
+
+int git_repository_set_workdir(
+	git_repository *repo, const char *workdir, int update_gitlink)
 {
+	int error = 0;
 	git_buf path = GIT_BUF_INIT;
 
 	assert(repo && workdir);
@@ -952,11 +1000,37 @@ int git_repository_set_workdir(git_repository *repo, const char *workdir)
 	if (git_path_prettify_dir(&path, workdir, NULL) < 0)
 		return -1;
 
-	git__free(repo->workdir);
+	if (repo->workdir && strcmp(repo->workdir, path.ptr) == 0)
+		return 0;
 
-	repo->workdir = git_buf_detach(&path);
-	repo->is_bare = 0;
-	return 0;
+	if (update_gitlink) {
+		git_config *config;
+
+		if (git_repository_config__weakptr(&config, repo) < 0)
+			return -1;
+
+		error = write_gitlink(path.ptr, git_repository_path(repo));
+
+		/* passthrough error means gitlink is unnecessary */
+		if (error == GIT_PASSTHROUGH)
+			error = git_config_delete(config, "core.worktree");
+		else if (!error)
+			error = git_config_set_string(config, "core.worktree", path.ptr);
+
+		if (!error)
+			error = git_config_set_bool(config, "core.bare", false);
+	}
+
+	if (!error) {
+		char *old_workdir = repo->workdir;
+
+		repo->workdir = git_buf_detach(&path);
+		repo->is_bare = 0;
+
+		git__free(old_workdir);
+	}
+
+	return error;
 }
 
 int git_repository_is_bare(git_repository *repo)
diff --git a/src/util.h b/src/util.h
index abdd543..a84dcab 100644
--- a/src/util.h
+++ b/src/util.h
@@ -211,7 +211,7 @@ GIT_INLINE(bool) git__isdigit(int c)
 
 GIT_INLINE(bool) git__isspace(int c)
 {
-    return (c == ' ' || c == '\t' || c == '\n' || c == '\f' || c == '\r' || c == '\v');
+    return (c == ' ' || c == '\t' || c == '\n' || c == '\f' || c == '\r' || c == '\v' || c == 0x85 /* Unicode CR+LF */);
 }
 
 GIT_INLINE(bool) git__iswildcard(int c)
diff --git a/tests-clar/config/read.c b/tests-clar/config/read.c
index f33bdd8..a8504da 100644
--- a/tests-clar/config/read.c
+++ b/tests-clar/config/read.c
@@ -191,6 +191,81 @@ void test_config_read__escaping_quotes(void)
 	git_config_free(cfg);
 }
 
+static int count_cfg_entries(
+	const char *var_name, const char *value, void *payload)
+{
+	int *count = payload;
+	GIT_UNUSED(var_name);
+	GIT_UNUSED(value);
+	(*count)++;
+	return 0;
+}
+
+static int cfg_callback_countdown(
+	const char *var_name, const char *value, void *payload)
+{
+	int *count = payload;
+	GIT_UNUSED(var_name);
+	GIT_UNUSED(value);
+	(*count)--;
+	if (*count == 0)
+		return -100;
+	return 0;
+}
+
+void test_config_read__foreach(void)
+{
+	git_config *cfg;
+	int count, ret;
+
+	cl_git_pass(git_config_open_ondisk(&cfg, cl_fixture("config/config9")));
+
+	count = 0;
+	cl_git_pass(git_config_foreach(cfg, count_cfg_entries, &count));
+	cl_assert_equal_i(5, count);
+
+	count = 3;
+	cl_git_fail(ret = git_config_foreach(cfg, cfg_callback_countdown, &count));
+	cl_assert_equal_i(-100, ret);
+
+	git_config_free(cfg);
+}
+
+void test_config_read__foreach_match(void)
+{
+	git_config *cfg;
+	int count;
+
+	cl_git_pass(git_config_open_ondisk(&cfg, cl_fixture("config/config9")));
+
+	count = 0;
+	cl_git_pass(
+		git_config_foreach_match(cfg, "core.*", count_cfg_entries, &count));
+	cl_assert_equal_i(3, count);
+
+	count = 0;
+	cl_git_pass(
+		git_config_foreach_match(cfg, "remote\\.ab.*", count_cfg_entries, &count));
+	cl_assert_equal_i(2, count);
+
+	count = 0;
+	cl_git_pass(
+		git_config_foreach_match(cfg, ".*url$", count_cfg_entries, &count));
+	cl_assert_equal_i(2, count);
+
+	count = 0;
+	cl_git_pass(
+		git_config_foreach_match(cfg, ".*dummy.*", count_cfg_entries, &count));
+	cl_assert_equal_i(2, count);
+
+	count = 0;
+	cl_git_pass(
+		git_config_foreach_match(cfg, ".*nomatch.*", count_cfg_entries, &count));
+	cl_assert_equal_i(0, count);
+
+	git_config_free(cfg);
+}
+
 #if 0
 
 BEGIN_TEST(config10, "a repo's config overrides the global config")
diff --git a/tests-clar/core/buffer.c b/tests-clar/core/buffer.c
index 6a718f4..996cb7b 100644
--- a/tests-clar/core/buffer.c
+++ b/tests-clar/core/buffer.c
@@ -611,3 +611,50 @@ void test_core_buffer__11(void)
 
 	git_buf_free(&a);
 }
+
+void test_core_buffer__rfind_variants(void)
+{
+	git_buf a = GIT_BUF_INIT;
+	ssize_t len;
+
+	cl_git_pass(git_buf_sets(&a, "/this/is/it/"));
+
+	len = (ssize_t)git_buf_len(&a);
+
+	cl_assert(git_buf_rfind(&a, '/') == len - 1);
+	cl_assert(git_buf_rfind_next(&a, '/') == len - 4);
+
+	cl_assert(git_buf_rfind(&a, 'i') == len - 3);
+	cl_assert(git_buf_rfind_next(&a, 'i') == len - 3);
+
+	cl_assert(git_buf_rfind(&a, 'h') == 2);
+	cl_assert(git_buf_rfind_next(&a, 'h') == 2);
+
+	cl_assert(git_buf_rfind(&a, 'q') == -1);
+	cl_assert(git_buf_rfind_next(&a, 'q') == -1);
+
+	git_buf_clear(&a);
+}
+
+void test_core_buffer__puts_escaped(void)
+{
+	git_buf a = GIT_BUF_INIT;
+
+	git_buf_clear(&a);
+	cl_git_pass(git_buf_puts_escaped(&a, "this is a test", "", ""));
+	cl_assert_equal_s("this is a test", a.ptr);
+
+	git_buf_clear(&a);
+	cl_git_pass(git_buf_puts_escaped(&a, "this is a test", "t", "\\"));
+	cl_assert_equal_s("\\this is a \\tes\\t", a.ptr);
+
+	git_buf_clear(&a);
+	cl_git_pass(git_buf_puts_escaped(&a, "this is a test", "i ", "__"));
+	cl_assert_equal_s("th__is__ __is__ a__ test", a.ptr);
+
+	git_buf_clear(&a);
+	cl_git_pass(git_buf_puts_escape_regex(&a, "^match\\s*[A-Z]+.*"));
+	cl_assert_equal_s("\\^match\\\\s\\*\\[A-Z\\]\\+\\.\\*", a.ptr);
+
+	git_buf_free(&a);
+}
diff --git a/tests-clar/core/path.c b/tests-clar/core/path.c
index d826612..864393b 100644
--- a/tests-clar/core/path.c
+++ b/tests-clar/core/path.c
@@ -418,3 +418,54 @@ void test_core_path__13_cannot_prettify_a_non_existing_file(void)
 
 	git_buf_free(&p);
 }
+
+void test_core_path__14_apply_relative(void)
+{
+	git_buf p = GIT_BUF_INIT;
+
+	cl_git_pass(git_buf_sets(&p, "/this/is/a/base"));
+
+	cl_git_pass(git_path_apply_relative(&p, "../test"));
+	cl_assert_equal_s("/this/is/a/test", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../../the/./end"));
+	cl_assert_equal_s("/this/is/the/end", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "./of/this/../the/string"));
+	cl_assert_equal_s("/this/is/the/end/of/the/string", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../../../../../.."));
+	cl_assert_equal_s("/this/", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../../../../../"));
+	cl_assert_equal_s("/", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../../../../.."));
+	cl_assert_equal_s("/", p.ptr);
+
+
+	cl_git_pass(git_buf_sets(&p, "d:/another/test"));
+
+	cl_git_pass(git_path_apply_relative(&p, "../../../../.."));
+	cl_assert_equal_s("d:/", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "from/here/to/../and/./back/."));
+	cl_assert_equal_s("d:/from/here/and/back/", p.ptr);
+
+
+	cl_git_pass(git_buf_sets(&p, "https://my.url.com/test.git"));
+
+	cl_git_pass(git_path_apply_relative(&p, "../another.git"));
+	cl_assert_equal_s("https://my.url.com/another.git", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../full/path/url.patch"));
+	cl_assert_equal_s("https://my.url.com/full/path/url.patch", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, ".."));
+	cl_assert_equal_s("https://my.url.com/full/path/", p.ptr);
+
+	cl_git_pass(git_path_apply_relative(&p, "../../../../../"));
+	cl_assert_equal_s("https://", p.ptr);
+
+	git_buf_free(&p);
+}
diff --git a/tests-clar/repo/setters.c b/tests-clar/repo/setters.c
index 6242d85..cd6e389 100644
--- a/tests-clar/repo/setters.c
+++ b/tests-clar/repo/setters.c
@@ -2,6 +2,8 @@
 #include "buffer.h"
 #include "posix.h"
 #include "util.h"
+#include "path.h"
+#include "fileops.h"
 
 static git_repository *repo;
 
@@ -16,7 +18,7 @@ void test_repo_setters__cleanup(void)
 {
 	git_repository_free(repo);
 	cl_fixture_cleanup("testrepo.git");
-	cl_must_pass(p_rmdir("new_workdir"));
+	cl_fixture_cleanup("new_workdir");
 }
 
 void test_repo_setters__setting_a_workdir_turns_a_bare_repository_into_a_standard_one(void)
@@ -24,7 +26,7 @@ void test_repo_setters__setting_a_workdir_turns_a_bare_repository_into_a_standar
 	cl_assert(git_repository_is_bare(repo) == 1);
 
 	cl_assert(git_repository_workdir(repo) == NULL);
-	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir"));
+	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir", false));
 
 	cl_assert(git_repository_workdir(repo) != NULL);
 	cl_assert(git_repository_is_bare(repo) == 0);
@@ -32,9 +34,30 @@ void test_repo_setters__setting_a_workdir_turns_a_bare_repository_into_a_standar
 
 void test_repo_setters__setting_a_workdir_prettifies_its_path(void)
 {
-	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir"));
+	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir", false));
 
-	cl_assert(git__suffixcmp(git_repository_workdir(repo), "/") == 0);
+	cl_assert(git__suffixcmp(git_repository_workdir(repo), "new_workdir/") == 0);
+}
+
+void test_repo_setters__setting_a_workdir_creates_a_gitlink(void)
+{
+	git_config *cfg;
+	const char *val;
+	git_buf content = GIT_BUF_INIT;
+
+	cl_git_pass(git_repository_set_workdir(repo, "./new_workdir", true));
+
+	cl_assert(git_path_isfile("./new_workdir/.git"));
+
+	cl_git_pass(git_futils_readbuffer(&content, "./new_workdir/.git"));
+	cl_assert(git__prefixcmp(git_buf_cstr(&content), "gitdir: ") == 0);
+	cl_assert(git__suffixcmp(git_buf_cstr(&content), "testrepo.git/") == 0);
+	git_buf_free(&content);
+
+	cl_git_pass(git_repository_config(&cfg, repo));
+	cl_git_pass(git_config_get_string(&val, cfg, "core.worktree"));
+	cl_assert(git__suffixcmp(val, "new_workdir/") == 0);
+	git_config_free(cfg);
 }
 
 void test_repo_setters__setting_a_new_index_on_a_repo_which_has_already_loaded_one_properly_honors_the_refcount(void)
diff --git a/tests-clar/status/worktree.c b/tests-clar/status/worktree.c
index 3670b72..fed81e5 100644
--- a/tests-clar/status/worktree.c
+++ b/tests-clar/status/worktree.c
@@ -459,7 +459,7 @@ void test_status_worktree__status_file_without_index_or_workdir(void)
 	cl_git_pass(p_mkdir("wd", 0777));
 
 	cl_git_pass(git_repository_open(&repo, cl_fixture("testrepo.git")));
-	cl_git_pass(git_repository_set_workdir(repo, "wd"));
+	cl_git_pass(git_repository_set_workdir(repo, "wd", false));
 
 	cl_git_pass(git_index_open(&index, "empty-index"));
 	cl_assert_equal_i(0, git_index_entrycount(index));
@@ -500,7 +500,7 @@ void test_status_worktree__status_file_with_clean_index_and_empty_workdir(void)
 	cl_git_pass(p_mkdir("wd", 0777));
 
 	cl_git_pass(git_repository_open(&repo, cl_fixture("testrepo.git")));
-	cl_git_pass(git_repository_set_workdir(repo, "wd"));
+	cl_git_pass(git_repository_set_workdir(repo, "wd", false));
 
 	cl_git_pass(git_index_open(&index, "my-index"));
 	fill_index_wth_head_entries(repo, index);