From 12d2039f683a0c00722dd76116b5e2df87a20f2a Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Sun, 22 Jan 2023 11:27:37 +0100
Subject: [PATCH] CString: Add strnlen() and strndup()

---
 luna/include/luna/CString.h |  4 ++++
 luna/src/CString.cpp        | 24 ++++++++++++++++++++++--
 2 files changed, 26 insertions(+), 2 deletions(-)

diff --git a/luna/include/luna/CString.h b/luna/include/luna/CString.h
index 68bc930f..db7991d9 100644
--- a/luna/include/luna/CString.h
+++ b/luna/include/luna/CString.h
@@ -7,12 +7,16 @@ extern "C"
     void* memset(void* buf, int c, usize n);
     int memcmp(const void* a, const void* b, usize n);
     void* memmove(void* dest, const void* src, usize n);
+
     usize strlen(const char* str);
+    usize strnlen(const char* str, usize max);
+
     int strcmp(const char* a, const char* b);
 
     usize wcslen(const wchar_t* str);
 
     char* strdup(const char* str);
+    char* strndup(const char* str, usize max);
 
     // Copies len bytes from src into dest and adds a null terminator.
     // FIXME: Replace this invented function with strlcpy().
diff --git a/luna/src/CString.cpp b/luna/src/CString.cpp
index 1fbb41d2..b853c471 100644
--- a/luna/src/CString.cpp
+++ b/luna/src/CString.cpp
@@ -46,6 +46,14 @@ extern "C"
         return (usize)(i - str);
     }
 
+    usize strnlen(const char* str, usize max)
+    {
+        const char* i = str;
+        for (; max, *i; ++i, --max)
+            ;
+        return (usize)(i - str);
+    }
+
     int strcmp(const char* a, const char* b)
     {
         while (*a && (*a == *b))
@@ -68,10 +76,22 @@ extern "C"
     {
         const usize len = strlen(str);
 
-        char* dest = (char*)malloc_impl(len + 1).value_or(nullptr);
+        char* dest = (char*)calloc_impl(len + 1, 1).value_or(nullptr);
         if (!dest) return nullptr;
 
-        memcpy(dest, str, len + 1);
+        memcpy(dest, str, len);
+
+        return dest;
+    }
+
+    char* strndup(const char* str, usize max)
+    {
+        const usize len = strnlen(str, max);
+
+        char* dest = (char*)calloc_impl(len + 1, 1).value_or(nullptr);
+        if (!dest) return nullptr;
+
+        memcpy(dest, str, len);
 
         return dest;
     }