From 097ab82529f56ccf99b492adce94a3acb50af83a Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Thu, 5 Dec 2024 08:30:06 +0200
Subject: [PATCH] userspace: Implement `basename` utility

---
 userspace/programs/CMakeLists.txt          |  1 +
 userspace/programs/basename/CMakeLists.txt |  8 ++++++
 userspace/programs/basename/main.cpp       | 30 ++++++++++++++++++++++
 3 files changed, 39 insertions(+)
 create mode 100644 userspace/programs/basename/CMakeLists.txt
 create mode 100644 userspace/programs/basename/main.cpp

diff --git a/userspace/programs/CMakeLists.txt b/userspace/programs/CMakeLists.txt
index dabff242..ec6ce9ce 100644
--- a/userspace/programs/CMakeLists.txt
+++ b/userspace/programs/CMakeLists.txt
@@ -1,5 +1,6 @@
 set(USERSPACE_PROGRAMS
 	bananfetch
+	basename
 	cat
 	cat-mmap
 	chmod
diff --git a/userspace/programs/basename/CMakeLists.txt b/userspace/programs/basename/CMakeLists.txt
new file mode 100644
index 00000000..0db75c99
--- /dev/null
+++ b/userspace/programs/basename/CMakeLists.txt
@@ -0,0 +1,8 @@
+set(SOURCES
+	main.cpp
+)
+
+add_executable(basename ${SOURCES})
+banan_link_library(basename libc)
+
+install(TARGETS basename OPTIONAL)
diff --git a/userspace/programs/basename/main.cpp b/userspace/programs/basename/main.cpp
new file mode 100644
index 00000000..7f116e27
--- /dev/null
+++ b/userspace/programs/basename/main.cpp
@@ -0,0 +1,30 @@
+#include <libgen.h>
+#include <stdio.h>
+#include <string.h>
+
+int usage(const char* argv0, int ret)
+{
+	FILE* fout = ret ? stderr : stdout;
+	fprintf(fout, "usage: %s STRING [SUFFIX]\n", argv0);
+	return ret;
+}
+
+int main(int argc, const char* argv[])
+{
+	if (argc != 2 && argc != 3)
+		return usage(argv[0], 1);
+
+	const char* result = basename(const_cast<char*>(argv[1]));
+	int result_len = strlen(result);
+
+	if (argc == 3)
+	{
+		int suffix_len = strlen(argv[2]);
+		if (result_len >= suffix_len && strcmp(result - suffix_len, argv[2]) == 0)
+			result_len -= suffix_len;
+	}
+
+	printf("%.*s\n", result_len, result);
+
+	return 0;
+}