Add support for macros and cache flush API.

Add support for git attribute macro definitions.  Also, add
support for cache flush API to clear the attribute file content
cache when needed.

Additionally, improved the handling of global and system files,
making common utility functions in fileops and converting config
and attr to both use the common functions.

Adds a bunch more tests and fixed some memory leaks.  Note that
adding macros required me to use refcounted attribute assignment
definitions, which complicated, but probably improved memory usage.

1 files changed, 131 insertions, 0 deletions

diff --git a/src/fileops.c b/src/fileops.c
index fb2f954d7..5eb7bf6ec 100644
--- a/src/fileops.c
+++ b/src/fileops.c
@@ -403,3 +403,134 @@ int git_futils_contains_file(git_buf *base, const char *file, int append_if_exis
 	return _check_dir_contents(base, file, append_if_exists, &git_futils_isfile);
 }
 
+int git_futils_find_global_file(git_buf *path, const char *filename)
+{
+	int error;
+	const char *home = getenv("HOME");
+
+#ifdef GIT_WIN32
+	if (home == NULL)
+		home = getenv("USERPROFILE");
+#endif
+
+	if (home == NULL)
+		return git__throw(GIT_EOSERR, "Failed to open global %s file. "
+			"Cannot locate the user's home directory.", filename);
+
+	if ((error = git_buf_joinpath(path, home, filename)) < GIT_SUCCESS)
+		return error;
+
+	if (git_futils_exists(path->ptr) < GIT_SUCCESS) {
+		git_buf_clear(path);
+		return GIT_ENOTFOUND;
+	}
+
+	return GIT_SUCCESS;
+}
+
+#ifdef GIT_WIN32
+typedef struct {
+	wchar_t *path;
+	DWORD len;
+} win32_path;
+
+static const win32_path *win32_system_root(void)
+{
+	static win32_path s_root = { 0, 0 };
+
+	if (s_root.path == NULL) {
+		const wchar_t *root_tmpl = L"%PROGRAMFILES%\\Git\\etc\\";
+
+		s_root.len = ExpandEnvironmentStringsW(root_tmpl, NULL, 0);
+
+		if (s_root.len <= 0) {
+			git__throw(GIT_EOSERR, "Failed to expand environment strings");
+			return NULL;
+		}
+
+		s_root.path = git__calloc(s_root.len, sizeof(wchar_t));
+		if (s_root.path == NULL)
+			return NULL;
+
+		if (ExpandEnvironmentStringsW(root_tmpl, s_root.path, s_root.len) != s_root.len) {
+			git__throw(GIT_EOSERR, "Failed to expand environment strings");
+			git__free(s_root.path);
+			s_root.path = NULL;
+			return NULL;
+		}
+	}
+
+	return &s_root;
+}
+
+static int win32_find_system_file(git_buf *path, const char *filename)
+{
+	int error = GIT_SUCCESS;
+	const win32_path *root = win32_system_root();
+	size_t len;
+	wchar_t *file_utf16 = NULL, *scan;
+	char *file_utf8 = NULL;
+
+	if (!root || !filename || (len = strlen(filename)) == 0)
+		return GIT_ENOTFOUND;
+
+	/* allocate space for wchar_t path to file */
+	file_utf16 = git__calloc(root->len + len + 2, sizeof(wchar_t));
+	if (!file_utf16)
+		return GIT_ENOMEM;
+
+	/* append root + '\\' + filename as wchar_t */
+	memcpy(file_utf16, root->path, root->len * sizeof(wchar_t));
+
+	if (*filename == '/' || *filename == '\\')
+		filename++;
+
+	if (gitwin_append_utf16(file_utf16 + root->len - 1, filename, len + 1) !=
+		(int)len) {
+		error = git__throw(GIT_EOSERR, "Failed to build file path");
+		goto cleanup;
+	}
+
+	for (scan = file_utf16; *scan; scan++)
+		if (*scan == L'/')
+			*scan = L'\\';
+
+	/* check access */
+	if (_waccess(file_utf16, F_OK) < 0) {
+		error = GIT_ENOTFOUND;
+		goto cleanup;
+	}
+
+	/* convert to utf8 */
+	if ((file_utf8 = gitwin_from_utf16(file_utf16)) == NULL)
+		error = GIT_ENOMEM;
+
+	if (file_utf8) {
+		git_path_mkposix(file_utf8);
+		git_buf_attach(path, file_utf8, 0);
+	}
+
+cleanup:
+	git__free(file_utf16);
+
+	return error;
+}
+#endif
+
+int git_futils_find_system_file(git_buf *path, const char *filename)
+{
+	if (git_buf_joinpath(path, "/etc", filename) < GIT_SUCCESS)
+		return git_buf_lasterror(path);
+
+	if (git_futils_exists(path->ptr) == GIT_SUCCESS)
+		return GIT_SUCCESS;
+
+	git_buf_clear(path);
+
+#ifdef GIT_WIN32
+	return win32_find_system_file(path, filename);
+#else
+	return GIT_ENOTFOUND;
+#endif
+}
+