#include <math.h>
#include "../mc/mc_protocol.h"
-//#define MM_LEGACY_VERBOSE 1 /* define this to see which version of malloc gets used */
-
-/* The mmalloc() package can use a single implicit malloc descriptor
- for mmalloc/mrealloc/mfree operations which do not supply an explicit
- descriptor. This allows mmalloc() to provide
- backwards compatibility with the non-mmap'd version. */
-xbt_mheap_t __mmalloc_default_mdp = NULL;
+/* ***** Whether to use `mmalloc` of the undrlying malloc ***** */
static int __malloc_use_mmalloc;
return __malloc_use_mmalloc;
}
-static xbt_mheap_t __mmalloc_current_heap = NULL; /* The heap we are currently using. */
+/* ***** Current heap ***** */
+
+/* The mmalloc() package can use a single implicit malloc descriptor
+ for mmalloc/mrealloc/mfree operations which do not supply an explicit
+ descriptor. This allows mmalloc() to provide
+ backwards compatibility with the non-mmap'd version. */
+xbt_mheap_t __mmalloc_default_mdp = NULL;
+
+/* The heap we are currently using. */
+static xbt_mheap_t __mmalloc_current_heap = NULL;
xbt_mheap_t mmalloc_get_current_heap(void)
{
#ifdef MMALLOC_WANT_OVERRIDE_LEGACY
+/* ***** Temporary allocator
+ *
+ * This is used before we have found the real malloc implementation with dlsym.
+ */
+
+#define BUFFER_SIZE 32
+static size_t fake_alloc_index;
+static uint64_t buffer[BUFFER_SIZE];
+
/* Fake implementations, they are used to fool dlsym:
* dlsym used calloc and falls back to some other mechanism
* if this fails.
*/
-static void* mm_fake_calloc(size_t nmemb, size_t size) { return NULL; }
-static void* mm_fake_malloc(size_t n) { return NULL; }
-static void* mm_fake_realloc(void *p, size_t s) { return NULL; }
+static void* mm_fake_malloc(size_t n)
+{
+ // How many uint64_t do w need?
+ size_t count = n / sizeof(uint64_t);
+ if (n % sizeof(uint64_t))
+ count++;
+ // Check that we have enough availabel memory:
+ if (fake_alloc_index + count >= BUFFER_SIZE)
+ exit(127);
+ // Allocate it:
+ uint64_t* res = buffer + fake_alloc_index;
+ fake_alloc_index += count;
+ return res;
+}
+
+static void* mm_fake_calloc(size_t nmemb, size_t size)
+{
+ // This is fresh .bss data, we don't need to clear it:
+ size_t n = nmemb * size;
+ return mm_fake_malloc(n);
+}
+
+static void* mm_fake_realloc(void *p, size_t s)
+{
+ return mm_fake_malloc(s);
+}
+
+static void mm_fake_free(void *p)
+{
+}
/* Function signatures for the main malloc functions: */
typedef void* (*mm_malloc_t)(size_t size);
typedef void* (*mm_realloc_t)(void *ptr, size_t size);
/* Function pointers to the real/next implementations: */
-static mm_malloc_t mm_real_malloc = mm_fake_malloc;
+static mm_malloc_t mm_real_malloc;
static mm_free_t mm_real_free;
-static mm_calloc_t mm_real_calloc = mm_fake_calloc;
-static mm_realloc_t mm_real_realloc = mm_fake_realloc;
+static mm_calloc_t mm_real_calloc;
+static mm_realloc_t mm_real_realloc;
-#define GET_HEAP() __mmalloc_current_heap
+static int mm_initializing;
+static int mm_initialized;
/** Constructor functions used to initialize the malloc implementation
*/
static void __attribute__((constructor(101))) mm_legacy_constructor()
{
+ if (mm_initialized)
+ return;
+ mm_initializing = 1;
__malloc_use_mmalloc = getenv(MC_ENV_VARIABLE) ? 1 : 0;
if (__malloc_use_mmalloc) {
__mmalloc_current_heap = mmalloc_preinit();
} else {
- mm_real_realloc = (mm_realloc_t) dlsym(RTLD_NEXT, "realloc");
- mm_real_malloc = (mm_malloc_t) dlsym(RTLD_NEXT, "malloc");
- mm_real_free = (mm_free_t) dlsym(RTLD_NEXT, "free");
- mm_real_calloc = (mm_calloc_t) dlsym(RTLD_NEXT, "calloc");
+ mm_real_realloc = dlsym(RTLD_NEXT, "realloc");
+ mm_real_malloc = dlsym(RTLD_NEXT, "malloc");
+ mm_real_free = dlsym(RTLD_NEXT, "free");
+ mm_real_calloc = dlsym(RTLD_NEXT, "calloc");
}
+ mm_initializing = 0;
+ mm_initialized = 1;
}
+/* ***** malloc/free implementation
+ *
+ * They call either the underlying/native/RTLD_NEXT implementation (non MC mode)
+ * or the mm implementation (MC mode).
+ *
+ * If we are initializing the malloc subsystem, we call the fake/dummy `malloc`
+ * implementation. This is necessary because `dlsym` calls `malloc` and friends.
+ */
+
+#define GET_HEAP() __mmalloc_current_heap
+
void* malloc_no_memset(size_t n)
{
+ if (!mm_initialized) {
+ if (mm_initializing)
+ return mm_fake_malloc(n);
+ mm_legacy_constructor();
+ }
+
if (!__malloc_use_mmalloc) {
return mm_real_malloc(n);
}
void *malloc(size_t n)
{
+ if (!mm_initialized) {
+ if (mm_initializing)
+ return mm_fake_malloc(n);
+ mm_legacy_constructor();
+ }
+
if (!__malloc_use_mmalloc) {
return mm_real_malloc(n);
}
void *calloc(size_t nmemb, size_t size)
{
+ if (!mm_initialized) {
+ if (mm_initializing)
+ return mm_fake_calloc(nmemb, size);
+ mm_legacy_constructor();
+ }
+
if (!__malloc_use_mmalloc) {
return mm_real_calloc(nmemb, size);
}
void *realloc(void *p, size_t s)
{
+ if (!mm_initialized) {
+ if (mm_initializing)
+ return mm_fake_realloc(p, s);
+ mm_legacy_constructor();
+ }
+
if (!__malloc_use_mmalloc) {
return mm_real_realloc(p, s);
}
void free(void *p)
{
+ if (!mm_initialized) {
+ if (mm_initializing)
+ return mm_fake_free(p);
+ mm_legacy_constructor();
+ }
+
if (!__malloc_use_mmalloc) {
mm_real_free(p);
return;
