Merge pull request #1417 from arrbee/opts-for-paths

Implement opts interface for global/system file search paths

1 files changed, 160 insertions, 49 deletions

diff --git a/src/fileops.c b/src/fileops.c
index e33377eac..d6244711f 100644
--- a/src/fileops.c
+++ b/src/fileops.c
@@ -558,75 +558,186 @@ clean_up:
 	return error;
 }
 
-int git_futils_find_system_file(git_buf *path, const char *filename)
+
+static int git_futils_guess_system_dirs(git_buf *out)
 {
 #ifdef GIT_WIN32
-	// try to find git.exe/git.cmd on path
-	if (!win32_find_system_file_using_path(path, filename))
-		return 0;
+	return git_win32__find_system_dirs(out);
+#else
+	return git_buf_sets(out, "/etc");
+#endif
+}
 
-	// try to find msysgit installation path using registry
-	if (!win32_find_system_file_using_registry(path, filename))
-		return 0;
+static int git_futils_guess_global_dirs(git_buf *out)
+{
+#ifdef GIT_WIN32
+	return git_win32__find_global_dirs(out);
 #else
-	if (git_buf_joinpath(path, "/etc", filename) < 0)
-		return -1;
+	return git_buf_sets(out, getenv("HOME"));
+#endif
+}
 
-	if (git_path_exists(path->ptr) == true)
-		return 0;
+static int git_futils_guess_xdg_dirs(git_buf *out)
+{
+#ifdef GIT_WIN32
+	return git_win32__find_xdg_dirs(out);
+#else
+	const char *env = NULL;
+
+	if ((env = getenv("XDG_CONFIG_HOME")) != NULL)
+		return git_buf_joinpath(out, env, "git");
+	else if ((env = getenv("HOME")) != NULL)
+		return git_buf_joinpath(out, env, ".config/git");
+
+	git_buf_clear(out);
+	return 0;
 #endif
+}
 
-	git_buf_clear(path);
-	giterr_set(GITERR_OS, "The system file '%s' doesn't exist", filename);
-	return GIT_ENOTFOUND;
+typedef int (*git_futils_dirs_guess_cb)(git_buf *out);
+
+static git_buf git_futils__dirs[GIT_FUTILS_DIR__MAX] =
+	{ GIT_BUF_INIT, GIT_BUF_INIT, GIT_BUF_INIT };
+
+static git_futils_dirs_guess_cb git_futils__dir_guess[GIT_FUTILS_DIR__MAX] = {
+	git_futils_guess_system_dirs,
+	git_futils_guess_global_dirs,
+	git_futils_guess_xdg_dirs,
+};
+
+static int git_futils_check_selector(git_futils_dir_t which)
+{
+	if (which < GIT_FUTILS_DIR__MAX)
+		return 0;
+	giterr_set(GITERR_INVALID, "config directory selector out of range");
+	return -1;
 }
 
-int git_futils_find_global_file(git_buf *path, const char *filename)
+int git_futils_dirs_get(const git_buf **out, git_futils_dir_t which)
 {
-#ifdef GIT_WIN32
-	struct win32_path root;
-	static const wchar_t *tmpls[4] = {
-		L"%HOME%\\",
-		L"%HOMEDRIVE%%HOMEPATH%\\",
-		L"%USERPROFILE%\\",
-		NULL,
-	};
-	const wchar_t **tmpl;
-
-	for (tmpl = tmpls; *tmpl != NULL; tmpl++) {
-		/* try to expand environment variable, skipping if not set */
-		if (win32_expand_path(&root, *tmpl) != 0 || root.path[0] == L'%')
+	assert(out);
+
+	*out = NULL;
+
+	GITERR_CHECK_ERROR(git_futils_check_selector(which));
+
+	if (!git_buf_len(&git_futils__dirs[which]))
+		GITERR_CHECK_ERROR(
+			git_futils__dir_guess[which](&git_futils__dirs[which]));
+
+	*out = &git_futils__dirs[which];
+	return 0;
+}
+
+int git_futils_dirs_get_str(char *out, size_t outlen, git_futils_dir_t which)
+{
+	const git_buf *path = NULL;
+
+	GITERR_CHECK_ERROR(git_futils_check_selector(which));
+	GITERR_CHECK_ERROR(git_futils_dirs_get(&path, which));
+
+	if (!out || path->size >= outlen) {
+		giterr_set(GITERR_NOMEMORY, "Buffer is too short for the path");
+		return GIT_EBUFS;
+	}
+
+	git_buf_copy_cstr(out, outlen, path);
+	return 0;
+}
+
+#define PATH_MAGIC "$PATH"
+
+int git_futils_dirs_set(git_futils_dir_t which, const char *search_path)
+{
+	const char *expand_path = NULL;
+	git_buf merge = GIT_BUF_INIT;
+
+	GITERR_CHECK_ERROR(git_futils_check_selector(which));
+
+	if (search_path != NULL)
+		expand_path = strstr(search_path, PATH_MAGIC);
+
+	/* init with default if not yet done and needed (ignoring error) */
+	if ((!search_path || expand_path) &&
+		!git_buf_len(&git_futils__dirs[which]))
+		git_futils__dir_guess[which](&git_futils__dirs[which]);
+
+	/* if $PATH is not referenced, then just set the path */
+	if (!expand_path)
+		return git_buf_sets(&git_futils__dirs[which], search_path);
+
+	/* otherwise set to join(before $PATH, old value, after $PATH) */
+	if (expand_path > search_path)
+		git_buf_set(&merge, search_path, expand_path - search_path);
+
+	if (git_buf_len(&git_futils__dirs[which]))
+		git_buf_join(&merge, GIT_PATH_LIST_SEPARATOR,
+			merge.ptr, git_futils__dirs[which].ptr);
+
+	expand_path += strlen(PATH_MAGIC);
+	if (*expand_path)
+		git_buf_join(&merge, GIT_PATH_LIST_SEPARATOR, merge.ptr, expand_path);
+
+	git_buf_swap(&git_futils__dirs[which], &merge);
+	git_buf_free(&merge);
+
+	return git_buf_oom(&git_futils__dirs[which]) ? -1 : 0;
+}
+
+void git_futils_dirs_free(void)
+{
+	int i;
+	for (i = 0; i < GIT_FUTILS_DIR__MAX; ++i)
+		git_buf_free(&git_futils__dirs[i]);
+}
+
+static int git_futils_find_in_dirlist(
+	git_buf *path, const char *name, git_futils_dir_t which, const char *label)
+{
+	size_t len;
+	const char *scan, *next = NULL;
+	const git_buf *syspath;
+
+	GITERR_CHECK_ERROR(git_futils_dirs_get(&syspath, which));
+
+	for (scan = git_buf_cstr(syspath); scan; scan = next) {
+		for (next = strchr(scan, GIT_PATH_LIST_SEPARATOR);
+			 next && next > scan && next[-1] == '\\';
+			 next = strchr(next + 1, GIT_PATH_LIST_SEPARATOR))
+			/* find unescaped separator or end of string */;
+
+		len = next ? (size_t)(next++ - scan) : strlen(scan);
+		if (!len)
 			continue;
 
-		/* try to look up file under path */
-		if (!win32_find_file(path, &root, filename))
+		GITERR_CHECK_ERROR(git_buf_set(path, scan, len));
+		GITERR_CHECK_ERROR(git_buf_joinpath(path, path->ptr, name));
+
+		if (git_path_exists(path->ptr))
 			return 0;
 	}
 
-	giterr_set(GITERR_OS, "The global file '%s' doesn't exist", filename);
 	git_buf_clear(path);
-
+	giterr_set(GITERR_OS, "The %s file '%s' doesn't exist", label, name);
 	return GIT_ENOTFOUND;
-#else
-	const char *home = getenv("HOME");
-
-	if (home == NULL) {
-		giterr_set(GITERR_OS, "Global file lookup failed. "
-			"Cannot locate the user's home directory");
-		return GIT_ENOTFOUND;
-	}
+}
 
-	if (git_buf_joinpath(path, home, filename) < 0)
-		return -1;
+int git_futils_find_system_file(git_buf *path, const char *filename)
+{
+	return git_futils_find_in_dirlist(
+		path, filename, GIT_FUTILS_DIR_SYSTEM, "system");
+}
 
-	if (git_path_exists(path->ptr) == false) {
-		giterr_set(GITERR_OS, "The global file '%s' doesn't exist", filename);
-		git_buf_clear(path);
-		return GIT_ENOTFOUND;
-	}
+int git_futils_find_global_file(git_buf *path, const char *filename)
+{
+	return git_futils_find_in_dirlist(
+		path, filename, GIT_FUTILS_DIR_GLOBAL, "global");
+}
 
-	return 0;
-#endif
+int git_futils_find_xdg_file(git_buf *path, const char *filename)
+{
+	return git_futils_find_in_dirlist(
+		path, filename, GIT_FUTILS_DIR_XDG, "global/xdg");
 }
 
 int git_futils_fake_symlink(const char *old, const char *new)