From 8c0a57f0c2368e0bb2021c064140f7f932b9706d Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sun, 16 Oct 2022 14:36:25 +0200
Subject: [PATCH] Kernel: Copy strrchr, dirname and basename over from libc

---
 kernel/include/std/libgen.h |  4 ++++
 kernel/include/std/string.h |  3 ++-
 kernel/src/std/libgen.cpp   | 47 +++++++++++++++++++++++++++++++++++++
 kernel/src/std/string.cpp   |  8 +++++++
 4 files changed, 61 insertions(+), 1 deletion(-)
 create mode 100644 kernel/include/std/libgen.h
 create mode 100644 kernel/src/std/libgen.cpp

diff --git a/kernel/include/std/libgen.h b/kernel/include/std/libgen.h
new file mode 100644
index 00000000..d9a7ec48
--- /dev/null
+++ b/kernel/include/std/libgen.h
@@ -0,0 +1,4 @@
+#pragma once
+
+char* basename(char* path);
+char* dirname(char* path);
\ No newline at end of file
diff --git a/kernel/include/std/string.h b/kernel/include/std/string.h
index ac1a2459..6a2543b3 100644
--- a/kernel/include/std/string.h
+++ b/kernel/include/std/string.h
@@ -19,4 +19,5 @@ void* memset(void* dest, int c, size_t n);
 int memcmp(const void* a, const void* b, size_t n);
 void* memmove(void* dest, void* src, size_t n);
 
-char* strdup(const char* src);
\ No newline at end of file
+char* strdup(const char* src);
+char* strrchr(const char* str, int c);
\ No newline at end of file
diff --git a/kernel/src/std/libgen.cpp b/kernel/src/std/libgen.cpp
new file mode 100644
index 00000000..908aee15
--- /dev/null
+++ b/kernel/src/std/libgen.cpp
@@ -0,0 +1,47 @@
+#include "std/libgen.h"
+#include "std/string.h"
+
+static char dot[] = ".";
+
+char* basename(char* path)
+{
+    // If path is NULL, or the string's length is 0, return .
+    if (!path) return dot;
+    size_t len = strlen(path);
+    if (!len) return dot;
+
+    // Strip trailing slashes.
+    char* it = path + len - 1;
+    while (*it == '/' && it != path) { it--; }
+    *(it + 1) = 0;
+    if (it == path) return path;
+
+    // Return path from the first character if there are no more slashes, or from the first character after the last
+    // slash.
+    char* beg = strrchr(path, '/');
+    if (!beg) return path;
+    return beg + 1;
+}
+
+char* dirname(char* path)
+{
+    // If path is NULL, or the string's length is 0, return .
+    if (!path) return dot;
+    size_t len = strlen(path);
+    if (!len) return dot;
+
+    // Strip trailing slashes.
+    char* it = path + len - 1;
+    while (*it == '/' && it != path) { it--; }
+    *(char*)(it + 1) = 0;
+    if (it == path) return path;
+
+    // Search for the last slash. If there is none, return .
+    // Otherwise, we end the string there and return.
+    char* end = strrchr(path, '/');
+    if (!end) return dot;
+    if (end != path) *end = 0;
+    else
+        *(end + 1) = 0;
+    return path;
+}
\ No newline at end of file
diff --git a/kernel/src/std/string.cpp b/kernel/src/std/string.cpp
index ef5481fd..79fe1d76 100644
--- a/kernel/src/std/string.cpp
+++ b/kernel/src/std/string.cpp
@@ -148,4 +148,12 @@ char* strdup(const char* src)
     char* duplicated = (char*)kmalloc(length + 1);
     memcpy(duplicated, src, length + 1);
     return duplicated;
+}
+
+char* strrchr(const char* str, int c)
+{
+    const char* s = str + strlen(str);
+    while (s != str && *s != (char)c) s--;
+    if (*s == (char)c) return const_cast<char*>(s);
+    return NULL;
 }
\ No newline at end of file