From 49ce94a6ab917b10b7829d92d68418a097380fc7 Mon Sep 17 00:00:00 2001
From: Daniel Ledda <dan.j.ledda@gmail.com>
Date: Wed, 25 Feb 2026 08:36:40 +0100
Subject: [PATCH] os file IO fixes linux

---
 os.h       |  4 ++--
 os_linux.c | 20 +++++++++++---------
 2 files changed, 13 insertions(+), 11 deletions(-)

diff --git a/os.h b/os.h
index dddee81..bfec7a2 100644
--- a/os.h
+++ b/os.h
@@ -11,8 +11,8 @@ void os_free(void *ptr, uint64 freeSize);
 
 // ### File IO ###
 string os_readEntireFile(Arena *arena, string filename);
-bool os_writeEntireFile(Arena *arena, string filename, const byte *contents, uint64 contentsLength);
-bool os_fileAppend(Arena *arena, string filename, const byte *contents, uint64 contentsLength);
+bool os_writeEntireFile(string filename, const byte *contents, uint64 contentsLength);
+bool os_fileAppend(string filename, const byte *contents, uint64 contentsLength);
 
 // ### Standard IO ###
 void os_print(StdStream target, const char *fmt, va_list argList);
diff --git a/os_linux.c b/os_linux.c
index 3ca4020..c292c7d 100644
--- a/os_linux.c
+++ b/os_linux.c
@@ -46,7 +46,7 @@ string os_readEntireFile(Arena *arena, string filename) {
         close(input);
         if (bytesRead == -1) {
             arenaPopTo(arena, readBuffer.str);
-            return s("");
+            readBuffer = s("");
         }
     } else {
         readBuffer = s("");
@@ -56,35 +56,37 @@ string os_readEntireFile(Arena *arena, string filename) {
     return readBuffer;
 }
 
-bool os_writeEntireFile(Arena *arena, string filename, const byte *contents, uint64 contentsLength) {
-    Scratch temp = scratchStart(&arena, 1);
+bool os_writeEntireFile(string filename, const byte *contents, uint64 contentsLength) {
+    Scratch temp = scratchStart(NULL, 0);
 
     bool result = false;
-    int output = open(cstring(temp.arena, filename), O_WRONLY);
+    struct stat st;
+    stat((char *)filename.str, &st);
+    int output = open(cstring(temp.arena, filename), O_WRONLY | O_CREAT, S_IRUSR | S_IWUSR);
     if (output) {
         int64 bytesWritten = write(output, contents, contentsLength);
         if (bytesWritten != -1) {
             result = true;
         }
-        close(output);
     }
+    close(output);
 
     scratchEnd(temp);
     return result;
 }
 
-bool os_fileAppend(Arena *arena, string filename, const byte *contents, uint64 contentsLength) {
-    Scratch temp = scratchStart(&arena, 1);
+bool os_fileAppend(string filename, const byte *contents, uint64 contentsLength) {
+    Scratch temp = scratchStart(NULL, 0);
 
     bool result = false;
-    int output = open(cstring(temp.arena, filename), O_APPEND);
+    int output = open(cstring(temp.arena, filename), O_WRONLY | O_APPEND);
     if (output) {
         int bytesWritten = write(output, contents, contentsLength);
         if (bytesWritten != -1) {
             result = true;
         }
-        close(output);
     }
+    close(output);
 
     scratchEnd(temp);
     return result;