From cccb4e6d5e44b87e1a99c7db0f691a9b89213ea1 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Mon, 2 Dec 2024 02:39:03 +0200
Subject: [PATCH] LibC: Implement basename and dirname

---
 userspace/libraries/LibC/CMakeLists.txt |  1 +
 userspace/libraries/LibC/libgen.cpp     | 69 +++++++++++++++++++++++++
 2 files changed, 70 insertions(+)
 create mode 100644 userspace/libraries/LibC/libgen.cpp

diff --git a/userspace/libraries/LibC/CMakeLists.txt b/userspace/libraries/LibC/CMakeLists.txt
index f0bef2c6..7fc564fc 100644
--- a/userspace/libraries/LibC/CMakeLists.txt
+++ b/userspace/libraries/LibC/CMakeLists.txt
@@ -10,6 +10,7 @@ set(LIBC_SOURCES
 	ftw.cpp
 	grp.cpp
 	inttypes.cpp
+	libgen.cpp
 	locale.cpp
 	malloc.cpp
 	math.cpp
diff --git a/userspace/libraries/LibC/libgen.cpp b/userspace/libraries/LibC/libgen.cpp
new file mode 100644
index 00000000..83150e2d
--- /dev/null
+++ b/userspace/libraries/LibC/libgen.cpp
@@ -0,0 +1,69 @@
+#include <libgen.h>
+#include <limits.h>
+#include <string.h>
+
+char* basename(char* path)
+{
+	static char buffer[PATH_MAX];
+
+	constexpr auto prep_string =
+		[](const char* str) -> char*
+		{
+			strcpy(buffer, str);
+			return buffer;
+		};
+
+	if (path == nullptr || path[0] == '\0')
+		return prep_string(".");
+
+	char* endp = path + strlen(path);
+
+	while (endp > path && endp[-1] == '/')
+		endp--;
+	if (endp == path)
+		return prep_string("/");
+
+	char* startp = endp;
+	while (startp > path && startp[-1] != '/')
+		startp--;
+
+	memcpy(buffer, startp, endp - startp);
+	buffer[endp - startp] = '\0';
+	return buffer;
+}
+
+char* dirname(char* path)
+{
+	static char buffer[PATH_MAX];
+
+	constexpr auto prep_string =
+		[](const char* str) -> char*
+		{
+			strcpy(buffer, str);
+			return buffer;
+		};
+
+	if (path == nullptr || path[0] == '\0')
+		return prep_string(".");
+
+	char* endp = path + strlen(path);
+
+	while (endp > path && endp[-1] == '/')
+		endp--;
+	if (endp == path)
+		return prep_string("/");
+
+	while (endp > path && endp[-1] != '/')
+		endp--;
+	if (endp == path)
+		return prep_string(".");
+
+	while (endp > path && endp[-1] == '/')
+		endp--;
+	if (endp == path)
+		return prep_string("/");
+
+	memcpy(buffer, path, endp - path);
+	buffer[endp - path] = '\0';
+	return buffer;
+}