3 files changed, 39 insertions, 24 deletions

diff --git a/arr.c b/arr.c
index 0491ef4..9d2220b 100644
--- a/arr.c
+++ b/arr.c
@@ -226,10 +226,19 @@ static void arrcstr_append_strn_(char **a, char const *s, size_t s_len) {
 	memcpy(*a + curr_len, s, s_len + 1);
 }
 
+static void arrcstr_shrink_(char **a, u32 new_len) {
+	ArrHeader *hdr = arr_hdr_(*a);
+	assert(hdr->cap > new_len);
+	hdr->len = new_len;
+	(*a)[new_len] = '\0';
+}
+
 // append to a C-string array
 #define arrcstr_append_str(a, s) arrcstr_append_strn_(&(a), (s), strlen(s))
 // take at most n bytes from s
 #define arrcstr_append_strn(a, s, n) arrcstr_append_strn_(&(a), (s), (n))
+// make the string smaller
+#define arrcstr_shrink(a, n) arrcstr_shrink_(&(a), (n))
 
 
 static void arr_test(void) {
diff --git a/base.h b/base.h
index f6b0452..9ecbda4 100644
--- a/base.h
+++ b/base.h
@@ -10,9 +10,12 @@
 #include <shlobj.h>
 #define PATH_SEPARATOR '\\'
 #define PATH_SEPARATOR_STR "\\"
+// on windows, let the user use forwards slashes as well as backslashes
+#define ALL_PATH_SEPARATORS "\\/"
 #else
 #define PATH_SEPARATOR '/'
 #define PATH_SEPARATOR_STR "/"
+#define ALL_PATH_SEPARATORS "/"
 #endif
 
 #include <stdbool.h>
diff --git a/ui.c b/ui.c
index 5d31d29..d682e83 100644
--- a/ui.c
+++ b/ui.c
@@ -42,30 +42,33 @@ static int qsort_file_entry_cmp(void const *av, void const *bv) {
 	return strcmp_case_insensitive(a->name, b->name);
 }
 
-// change directory of file selector.
-void file_selector_cd(Ted *ted, FileSelector *fs, char const *path) {
-	// @TODO: handle .. properly
-	if (path[0] == PATH_SEPARATOR
-#if _WIN32
-	// check for, e.g. C:\ at start of path
-		|| (strlen(path) >= 3 && path[1] == ':' && path[2] == '\\')
-#endif
-	) {
-		// this is an absolute path. discard our previous cwd.
-		arr_clear(fs->cwd);
+// cd to the directory `name`. `name` cannot include any path separators.
+static void file_selector_cd(FileSelector *fs, char const *name) {
+	if (*name == '\0' || streq(name, ".")) {
+		// no name, or .
+		return;
 	}
-	size_t path_len = strlen(path);
-	if (!path_len) return;
 
-	if (path_len > 1 && path[path_len - 1] == PATH_SEPARATOR)
-		--path_len;
-	
-	// add path separator to end
-	arrcstr_append_str(fs->cwd, PATH_SEPARATOR_STR);
-	arrcstr_append_strn(fs->cwd, path, path_len);
-
-	// clear search term
-	buffer_clear(&ted->line_buffer);
+	if (streq(name, "..")) {
+		// ..
+		char *last_sep = strrchr(fs->cwd, PATH_SEPARATOR);
+		if (last_sep) {
+			if (last_sep == fs->cwd // this is the starting "/" of a path
+			#if _WIN32
+				|| (last_sep == fs->cwd + 2 && fs->cwd[1] == ':') // this is the \ of C:\  .
+			#endif
+				) {
+				arrcstr_shrink(fs->cwd, (u32)(last_sep + 1 - fs->cwd)); // include the last separator
+			} else {
+				arrcstr_shrink(fs->cwd, (u32)(last_sep - fs->cwd));
+			}
+		}
+	} else {
+		// add path separator to end
+		arrcstr_append_str(fs->cwd, PATH_SEPARATOR_STR);
+		// add name itself
+		arrcstr_append_str(fs->cwd, name);
+	}
 }
 
 // returns the name of the selected file, or NULL
@@ -99,7 +102,7 @@ static char *file_selector_update(Ted *ted, FileSelector *fs) {
 						if (path) return str_dup(path);
 						break;
 					case FS_DIRECTORY:
-						file_selector_cd(ted, fs, name);
+						file_selector_cd(fs, name);
 						break;
 					default: break;
 					}
@@ -115,7 +118,7 @@ static char *file_selector_update(Ted *ted, FileSelector *fs) {
 				if (path) return str_dup(path);
 				break;
 			case FS_DIRECTORY:
-				file_selector_cd(ted, fs, name);
+				file_selector_cd(fs, name);
 				break;
 			default: break;
 			}