# HG changeset patch
# User Mike Becker <universe@uap-core.de>
# Date 1748001624 -7200
# Node ID 343eac5ac8245e2abcc65adafe851926dc361978
# Parent  2cf66dee40b888e9cc114a02cf8b19be4eb686ab
add base allocator to mempool

otherwise, mempools could not be used as
new default allocators

diff -r 2cf66dee40b8 -r 343eac5ac824 docs/Writerside/topics/mempool.h.md
--- a/docs/Writerside/topics/mempool.h.md	Fri May 23 13:36:11 2025 +0200
+++ b/docs/Writerside/topics/mempool.h.md	Fri May 23 14:00:24 2025 +0200
@@ -125,9 +125,13 @@
 In contrast to transferring an entire pool, if `obj` has a reference to `source->allocator`, it must be updated to `dest->allocator` manually.
 It is also possible to transfer registered memory from one pool to another, this way.
 
-The functions returns zero when the transfer was successful and non-zero if a necessary memory allocation was not possible,
-the `source` and `dest` pointers point to the same pool, or the pools have different type (simple, advanced, pure).
-In case of an error, no memory is transferred and both pools are in a valid state.
+The functions return zero when the transfer was successful, and non-zero under one of the following error conditions:
+- a necessary memory allocation was not possible
+- the `source` and `dest` pointers point to the same pool
+- the pools have a different type (simple, advanced, pure)
+- the pools have different base allocators (i.e. `cxDefaultAllocator` changed between creation of the pools)
+
+In case of an error, no memory is transferred and both pools remain unchanged and are in a valid state.
 
 
 ## Example
diff -r 2cf66dee40b8 -r 343eac5ac824 src/cx/mempool.h
--- a/src/cx/mempool.h	Fri May 23 13:36:11 2025 +0200
+++ b/src/cx/mempool.h	Fri May 23 14:00:24 2025 +0200
@@ -98,6 +98,9 @@
  * Should be the first member of an actual memory pool implementation.
  */
 struct cx_mempool_s {
+    /** The used allocator, initialized with the cxDefaultAllocator. */
+    const CxAllocator * const base_allocator;
+
     /** The provided allocator. */
     const CxAllocator *allocator;
 
diff -r 2cf66dee40b8 -r 343eac5ac824 src/mempool.c
--- a/src/mempool.c	Fri May 23 13:36:11 2025 +0200
+++ b/src/mempool.c	Fri May 23 14:00:24 2025 +0200
@@ -45,7 +45,7 @@
         errno = EOVERFLOW;
         return 1;
     } // LCOV_EXCL_STOP
-    void **newdata = cxReallocDefault(pool->data, newmsize);
+    void **newdata = cxRealloc(pool->base_allocator, pool->data, newmsize);
     if (newdata == NULL) return 1;
     pool->data = newdata;
     pool->capacity = newcap;
@@ -66,7 +66,7 @@
         errno = EOVERFLOW;
         return 1;
     } // LCOV_EXCL_STOP
-    void *newdata = cxReallocDefault(pool->registered, newmsize);
+    void *newdata = cxRealloc(pool->base_allocator, pool->registered, newmsize);
     if (newdata == NULL) return 1;
     pool->registered = newdata;
     pool->registered_capacity = newcap;
@@ -84,7 +84,7 @@
     }
 
     struct cx_mempool_memory_s *mem =
-        cxMallocDefault(sizeof(struct cx_mempool_memory_s) + n);
+        cxMalloc(pool->base_allocator, sizeof(struct cx_mempool_memory_s) + n);
     if (mem == NULL) return NULL;
     mem->destructor = NULL;
     pool->data[pool->size] = mem;
@@ -130,7 +130,7 @@
             if (pool->destr2) {
                 pool->destr2(pool->destr2_data, mem->c);
             }
-            cxFreeDefault(mem);
+            cxFree(pool->base_allocator, mem);
             size_t last_index = pool->size - 1;
             if (i != last_index) {
                 pool->data[i] = pool->data[last_index];
@@ -161,7 +161,7 @@
     struct cx_mempool_memory_s *mem =
         (void *) (((char *) ptr) - overhead);
     struct cx_mempool_memory_s *newm =
-        cxReallocDefault(mem, n + overhead);
+        cxRealloc(pool->base_allocator, mem, n + overhead);
 
     if (newm == NULL) return NULL;
     if (mem != newm) {
@@ -192,7 +192,7 @@
         if (has_destr2) {
             pool->destr2(pool->destr2_data, mem->c);
         }
-        cxFreeDefault(mem);
+        cxFree(pool->base_allocator, mem);
     }
 }
 
@@ -214,7 +214,7 @@
     }
 
     struct cx_mempool_memory2_s *mem =
-        cxMallocDefault(sizeof(struct cx_mempool_memory2_s) + n);
+        cxMalloc(pool->base_allocator, sizeof(struct cx_mempool_memory2_s) + n);
     if (mem == NULL) return NULL;
     mem->destructor = NULL;
     mem->data = NULL;
@@ -261,7 +261,7 @@
             if (pool->destr2) {
                 pool->destr2(pool->destr2_data, mem->c);
             }
-            cxFreeDefault(mem);
+            cxFree(pool->base_allocator, mem);
             size_t last_index = pool->size - 1;
             if (i != last_index) {
                 pool->data[i] = pool->data[last_index];
@@ -292,7 +292,7 @@
     struct cx_mempool_memory2_s *mem =
         (void *) (((char *) ptr) - overhead);
     struct cx_mempool_memory2_s *newm =
-        cxReallocDefault(mem, n + overhead);
+        cxRealloc(pool->base_allocator, mem, n + overhead);
 
     if (newm == NULL) return NULL;
     if (mem != newm) {
@@ -323,7 +323,7 @@
         if (has_destr2) {
             pool->destr2(pool->destr2_data, mem->c);
         }
-        cxFreeDefault(mem);
+        cxFree(pool->base_allocator, mem);
     }
 }
 
@@ -345,7 +345,7 @@
         return NULL; // LCOV_EXCL_LINE
     }
 
-    void *mem = cxMallocDefault(n);
+    void *mem = cxMalloc(pool->base_allocator, n);
     if (mem == NULL) return NULL;
     pool->data[pool->size] = mem;
     pool->size++;
@@ -384,7 +384,7 @@
             if (pool->destr2) {
                 pool->destr2(pool->destr2_data, ptr);
             }
-            cxFreeDefault(ptr);
+            cxFree(pool->base_allocator, ptr);
             size_t last_index = pool->size - 1;
             if (i != last_index) {
                 pool->data[i] = pool->data[last_index];
@@ -410,7 +410,7 @@
         return NULL;
     }
     struct cx_mempool_s *pool = p;
-    void *newm = cxReallocDefault(ptr, n);
+    void *newm = cxRealloc(pool->base_allocator, ptr, n);
     if (newm == NULL) return NULL;
     if (ptr != newm) {
         for (size_t i = 0; i < pool->size; i++) {
@@ -437,7 +437,7 @@
         if (has_destr2) {
             pool->destr2(pool->destr2_data, mem);
         }
-        cxFreeDefault(mem);
+        cxFree(pool->base_allocator, mem);
     }
 }
 
@@ -471,10 +471,10 @@
         cx_mempool_free_all_pure(pool);
     }
     cx_mempool_free_foreign(pool);
-    cxFreeDefault(pool->data);
-    cxFreeDefault(pool->registered);
-    cxFreeDefault((void*) pool->allocator);
-    cxFreeDefault(pool);
+    cxFree(pool->base_allocator, pool->data);
+    cxFree(pool->base_allocator, pool->registered);
+    cxFree(pool->base_allocator, (void*) pool->allocator);
+    cxFree(pool->base_allocator, pool);
 }
 
 void cxMempoolSetDestructor(
@@ -569,6 +569,7 @@
     }  // LCOV_EXCL_STOP
 
     provided_allocator->data = pool;
+    *((const CxAllocator**)&pool->base_allocator) = cxDefaultAllocator;
     pool->allocator = provided_allocator;
     if (type == CX_MEMPOOL_TYPE_SIMPLE) {
         provided_allocator->cl = &cx_mempool_simple_allocator_class;
@@ -600,8 +601,8 @@
     pool->destr2_data = data;
 }
 
-static void cx_mempool_free_transferred_allocator(void *al) {
-    cxFreeDefault(al);
+static void cx_mempool_free_transferred_allocator(void *base_al, void *al) {
+    cxFree(base_al, al);
 }
 
 int cxMempoolTransfer(
@@ -611,6 +612,7 @@
     // safety checks
     if (source == dest) return 1;
     if (source->allocator->cl != dest->allocator->cl) return 1;
+    if (source->base_allocator->cl != dest->base_allocator->cl) return 1;
 
     // ensure enough capacity in the destination pool
     if (cx_mempool_ensure_capacity(dest, dest->size + source->size)) {
@@ -622,7 +624,8 @@
     }
 
     // allocate a replacement allocator for the source pool
-    CxAllocator *new_source_allocator = cxMallocDefault(sizeof(CxAllocator));
+    CxAllocator *new_source_allocator =
+        cxMalloc(source->base_allocator, sizeof(CxAllocator));
     if (new_source_allocator == NULL) { // LCOV_EXCL_START
         return 1;
     } // LCOV_EXCL_STOP
@@ -640,10 +643,11 @@
 
     // register the old allocator with the new pool
     // we have to remove const-ness for this, but that's okay here
+    // also register the base allocator, s.t. the pool knows how to free it
     CxAllocator *transferred_allocator = (CxAllocator*) source->allocator;
     transferred_allocator->data = dest;
-    cxMempoolRegister(dest, transferred_allocator,
-        cx_mempool_free_transferred_allocator);
+    cxMempoolRegister2(dest, transferred_allocator,
+        cx_mempool_free_transferred_allocator, (void*)source->base_allocator);
 
     // prepare the source pool for re-use
     source->allocator = new_source_allocator;
@@ -661,8 +665,10 @@
         CxMempool *dest,
         const void *obj
 ) {
-    // safety check
+    // safety checks
     if (source == dest) return 1;
+    if (source->allocator->cl != dest->allocator->cl) return 1;
+    if (source->base_allocator->cl != dest->base_allocator->cl) return 1;
 
     // search for the object
     for (size_t i = 0; i < source->size; i++) {