feat(MemoryManager): Implement M_std_tracked

Functions like M_std, but also tracks allocated and freed memory,
allowing all allocated memory to be destroyed.

3 files changed, 152 insertions, 1 deletions

diff --git a/MemoryManager.c b/MemoryManager.c
index 53f906e..dd3a7fc 100644
--- a/MemoryManager.c
+++ b/MemoryManager.c
@@ -3,6 +3,8 @@
 #include <stdlib.h>
 #include <string.h>
 
+/** M_std **/
+
 Result
 std_alloc(MemoryManager mm, void **ptr, usize size) {
     if (NULL == ptr)
@@ -46,6 +48,154 @@ M_std() {
     };
 }
 
+/** M_std_tracked **/
+
+struct MemoryTracking {
+    usize alloc;
+    void **ptrs;
+};
+
+static inline Result
+MemoryTracking_store(struct MemoryTracking *mt, void *ptr) {
+    if (NULL == mt || NULL == ptr)
+        return R_NullArgument;
+
+    if (NULL == mt->ptrs || 0 == mt->alloc)
+        return R_Uninitialized;
+
+    usize index = 0;
+    while (index < mt->alloc && NULL != mt->ptrs[index]) {
+        ++index;
+    }
+
+    if (index == mt->alloc) {
+        mt->ptrs = realloc(mt->ptrs, sizeof(void*) * (mt->alloc << 1));
+        memset(mt->ptrs + (sizeof(void*) * mt->alloc), 0, sizeof(void*) * mt->alloc);
+
+        if (NULL == mt->ptrs) {
+            mt->alloc = 0;
+            return R_OutOfMemory;
+        }
+
+        mt->alloc <<= 1;
+    }
+
+    mt->ptrs[index] = ptr;
+    return R_Ok;
+}
+
+static inline Result
+MemoryTracking_remove(struct MemoryTracking *mt, void *ptr) {
+    if (NULL == mt || NULL == ptr)
+        return R_NullArgument;
+
+    if (NULL == mt->ptrs || 0 == mt->alloc)
+        return R_Uninitialized;
+
+    usize index = 0;
+    while (index < mt->alloc && ptr != mt->ptrs[index]) {
+        ++index;
+    }
+
+    if (index == mt->alloc)
+        return R_NotFound;
+
+    mt->ptrs[index] = NULL;
+    return R_Ok;
+}
+
+Result
+stdt_alloc(MemoryManager mm, void **ptr, usize size) {
+    if (NULL == ptr)
+        return R_NullArgument;
+
+    if (NULL == mm.priv)
+        return R_Uninitialized;
+
+    *ptr = malloc(size);
+    if (NULL == *ptr)
+        return R_Err;
+
+    return MemoryTracking_store(mm.priv, *ptr);
+}
+
+Result
+stdt_realloc(MemoryManager mm, void **ptr, usize new_size) {
+    if (NULL == ptr)
+        return R_NullArgument;
+
+    if (NULL == mm.priv)
+        return R_Uninitialized;
+
+    void *ptr_orig = *ptr;
+    *ptr = realloc(*ptr, new_size);
+
+    if (NULL == *ptr)
+        return R_Err;
+
+    if (ptr_orig != *ptr) {
+        RETURN_NOTOK(MemoryTracking_remove(mm.priv, ptr_orig));
+        RETURN_NOTOK(MemoryTracking_store(mm.priv, *ptr));
+    }
+    return R_Ok;
+}
+
+Result
+stdt_free(MemoryManager mm, void **ptr) {
+    if (NULL == ptr)
+        return R_NullArgument;
+
+    if (NULL == mm.priv)
+        return R_Uninitialized;
+
+    RETURN_NOTOK(MemoryTracking_remove(mm.priv, *ptr));
+
+    free(*ptr);
+    *ptr = NULL;
+
+    return R_Ok;
+}
+
+Result
+stdt_destroy(MemoryManager *mm) {
+    if (NULL == mm)
+        return R_NullArgument;
+
+    if (NULL == mm->priv)
+        return R_Uninitialized;
+
+    struct MemoryTracking *mt = mm->priv;
+
+    for (usize i = 0; i < mt->alloc; ++i) {
+        if (NULL != mt->ptrs[i])
+            free(mt->ptrs[i]);
+    }
+
+    free(mt->ptrs);
+    free(mt);
+    mm->priv = NULL;
+
+    return R_Ok;
+}
+
+MemoryManager
+M_std_tracked() {
+    struct MemoryTracking *mt = malloc(sizeof(struct MemoryTracking));
+    mt->alloc = 8;
+    mt->ptrs = malloc(sizeof(void*) * mt->alloc);
+    memset(mt->ptrs, 0, sizeof(void*) * mt->alloc);
+
+    return (MemoryManager) {
+        .alloc = &stdt_alloc,
+        .realloc = &stdt_realloc,
+        .free = &stdt_free,
+        .destroy = &stdt_destroy,
+        .priv = mt,
+    };
+}
+
+/* Helper functions */
+
 char*
 M_strdup(MemoryManager mm, const char* str) {
     if (NULL == str)
diff --git a/MemoryManager.h b/MemoryManager.h
index 3f1461b..1025e69 100644
--- a/MemoryManager.h
+++ b/MemoryManager.h
@@ -12,6 +12,7 @@ typedef struct MemoryManager {
 } MemoryManager;
 
 MemoryManager M_std();
+MemoryManager M_std_tracked();
 
 /* Helper functions */
 
diff --git a/example.c b/example.c
index 3808acd..6dc3525 100644
--- a/example.c
+++ b/example.c
@@ -7,7 +7,7 @@
 
 int
 main() {
-    MemoryManager g = M_bump(KiB(2)),
+    MemoryManager g = M_std_tracked(),
                   t = M_bump(KiB(4));
 
     String *hexes = V_new(&g, sizeof(String), 8);