From 39c331cd09b9d954e4bf2d109262165963f49779 Mon Sep 17 00:00:00 2001
From: Imbus <>
Date: Mon, 8 Sep 2025 07:38:22 +0200
Subject: [PATCH] Remove tracking of free state in freelist header since being
 in the list means it is also free

---
 freelist/freelist.c | 10 +---------
 freelist/freelist.h |  1 -
 freelist/main.c     |  1 -
 3 files changed, 1 insertion(+), 11 deletions(-)

diff --git a/freelist/freelist.c b/freelist/freelist.c
index cba0b1f..9b47a8d 100644
--- a/freelist/freelist.c
+++ b/freelist/freelist.c
@@ -33,7 +33,6 @@ int fl_init(FreeList *fl, uintptr_t start, uintptr_t end, size_t itemsize) {
     FreeListBlock *block = (FreeListBlock *)start;
     for (size_t i = 0; i < fl_capacity(fl); i++) {
         block->next = (FreeListBlock *)((void *)block + size);
-        block->block_state = FL_FREE;
         block = block->next;
     }
 
@@ -45,11 +44,10 @@ int fl_init(FreeList *fl, uintptr_t start, uintptr_t end, size_t itemsize) {
 
 /* Allocate some memory from the FreeList */
 void *fl_alloc(FreeList *fl) {
-    if (!fl->free || fl->free->block_state != FL_FREE)
+    if (!fl->free)
         return NULL;
 
     FreeListBlock *m = fl->free;
-    m->block_state = FL_USED;
 
     fl->free = fl->free->next;
     fl->allocated++;
@@ -65,11 +63,6 @@ int fl_free(FreeList *fl, void *ptr) {
 
     FreeListBlock *block = (FreeListBlock *)((uintptr_t)ptr - sizeof(FreeListBlock));
 
-    if (block->block_state != FL_USED) {
-        return EXIT_FAILURE; /* Block must be used */
-    }
-
-    block->block_state = FL_FREE;
     block->next = fl->free;
     fl->free = block;
     fl->allocated--;
@@ -109,7 +102,6 @@ size_t fl_check(FreeList *fl) {
 
     while (cursor->next != NULL) {
         avail++;
-        assert(cursor->block_state == FL_FREE);
         cursor = cursor->next;
     }
 
diff --git a/freelist/freelist.h b/freelist/freelist.h
index 885b58a..de12d5d 100644
--- a/freelist/freelist.h
+++ b/freelist/freelist.h
@@ -10,7 +10,6 @@
 
 typedef struct FreeListBlock {
     struct FreeListBlock *next;
-    uint8_t               block_state;
 } FreeListBlock;
 
 typedef struct {
diff --git a/freelist/main.c b/freelist/main.c
index 9d18438..0841d2e 100644
--- a/freelist/main.c
+++ b/freelist/main.c
@@ -51,7 +51,6 @@ int main() {
     assert(fl_free(&fl, a) == EXIT_SUCCESS);
     assert(fl_free(&fl, b) == EXIT_SUCCESS);
     assert(fl_free(&fl, c) == EXIT_SUCCESS);
-    assert(fl_free(&fl, a) == EXIT_FAILURE); // Double free
 
     printf("Available: %zu of %zu\n", fl_available(&fl), fl_capacity(&fl));