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gen/malloc.c /dev/null Libc-391
--- /dev/null
+++ Libc/Libc-391/gen/malloc.c
@@ -0,0 +1,788 @@
+/*
+ * Copyright (c) 1999 Apple Computer, Inc. All rights reserved.
+ *
+ * @APPLE_LICENSE_HEADER_START@
+ * 
+ * This file contains Original Code and/or Modifications of Original Code
+ * as defined in and that are subject to the Apple Public Source License
+ * Version 2.0 (the 'License'). You may not use this file except in
+ * compliance with the License. Please obtain a copy of the License at
+ * http://www.opensource.apple.com/apsl/ and read it before using this
+ * file.
+ * 
+ * The Original Code and all software distributed under the License are
+ * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
+ * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
+ * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
+ * Please see the License for the specific language governing rights and
+ * limitations under the License.
+ * 
+ * @APPLE_LICENSE_HEADER_END@
+ */
+ 
+#include <pthread_internals.h>
+
+#import <stdlib.h>
+#import <stdio.h>
+#import <string.h>
+#import <unistd.h>
+#import <objc/zone.h>
+#import <malloc/malloc.h>
+#import <fcntl.h>
+#import <crt_externs.h>
+#import <errno.h>
+#import <pthread_internals.h>
+
+#import "scalable_malloc.h"
+#import "stack_logging.h"
+
+#define USE_SLEEP_RATHER_THAN_ABORT	0
+
+#define INITIAL_ZONES	8  // After this number, we reallocate for new zones
+
+typedef void (malloc_logger_t)(unsigned type, unsigned arg1, unsigned arg2, unsigned arg3, unsigned result, unsigned num_hot_frames_to_skip);
+
+static pthread_lock_t _malloc_lock;
+static malloc_zone_t *initial_malloc_zones[INITIAL_ZONES] = {0};
+
+/* The following variables are exported for the benefit of performance tools */
+unsigned malloc_num_zones = 0;
+malloc_zone_t **malloc_zones = initial_malloc_zones;
+malloc_logger_t *malloc_logger = NULL;
+
+unsigned malloc_debug_flags = 0;
+
+unsigned malloc_check_start = 0; // 0 means don't check
+unsigned malloc_check_counter = 0;
+unsigned malloc_check_each = 1000;
+
+static int malloc_check_sleep = 100; // default 100 second sleep
+static int malloc_check_abort = 0; // default is to sleep, not abort
+
+static int malloc_free_abort = 0; // default is not to abort
+
+static int malloc_debug_file;
+
+#define MALLOC_LOCK()		LOCK(_malloc_lock)
+#define MALLOC_UNLOCK()		UNLOCK(_malloc_lock)
+
+#define MALLOC_LOG_TYPE_ALLOCATE	stack_logging_type_alloc
+#define MALLOC_LOG_TYPE_DEALLOCATE	stack_logging_type_dealloc
+#define MALLOC_LOG_TYPE_HAS_ZONE	stack_logging_flag_zone
+#define MALLOC_LOG_TYPE_CLEARED		stack_logging_flag_cleared
+
+/*********	Utilities	************/
+
+static inline malloc_zone_t * find_registered_zone(const void *, size_t *) __attribute__((always_inline));
+static inline malloc_zone_t *
+find_registered_zone(const void *ptr, size_t *returned_size) {
+    // locates the proper zone
+    // if zone found fills returnedSize; else returns NULL
+    // See comment in malloc_zone_register() about clients non locking to call this function
+    // Speed is critical for this function
+    unsigned	index = malloc_num_zones;
+    malloc_zone_t	**zones = malloc_zones;
+    while (index--) {
+        malloc_zone_t	*zone = *zones++;
+        size_t	size;
+        size = zone->size(zone, ptr);
+        if (size) {
+            if (returned_size) *returned_size = size;
+            return zone;
+        }
+    }
+    return NULL;
+}
+
+/*********	Creation and destruction	************/
+
+static void
+_malloc_initialize(void) {
+    // guaranteed to be called only once
+    (void)malloc_create_zone(0, 0);
+    malloc_set_zone_name(malloc_zones[0], "DefaultMallocZone");
+    LOCK_INIT(_malloc_lock);
+    // malloc_printf("%d registered zones\n", malloc_num_zones);
+    // malloc_printf("malloc_zones is at %p; malloc_num_zones is at %p\n", (unsigned)&malloc_zones, (unsigned)&malloc_num_zones);
+}
+
+static inline malloc_zone_t *inline_malloc_default_zone(void) __attribute__((always_inline));
+static inline malloc_zone_t *
+inline_malloc_default_zone(void) {
+    if (!malloc_num_zones) _malloc_initialize();
+    // malloc_printf("In inline_malloc_default_zone with %d %d\n", malloc_num_zones, malloc_has_debug_zone);
+    return malloc_zones[0];
+}
+
+malloc_zone_t *
+malloc_default_zone(void) {
+    return inline_malloc_default_zone();
+}
+
+static void
+set_flags_from_environment(void) {
+    const char *flag;
+    int fd;
+
+    flag = getenv("MallocLogFile");
+    if (flag) {
+	fd = open(flag, O_WRONLY|O_APPEND|O_CREAT, 0644);
+	if (fd >= 0) {
+	    malloc_debug_file = fd;
+	    fcntl(fd, F_SETFD, 0); // clear close-on-exec flag  XXX why?
+	} else {
+	    malloc_printf("Could not open %s, using stderr\n", flag);
+	}
+    }
+    if (getenv("MallocGuardEdges")) {
+	malloc_debug_flags = SCALABLE_MALLOC_ADD_GUARD_PAGES;
+	malloc_printf("protecting edges\n");
+	if (getenv("MallocDoNotProtectPrelude")) {
+	    malloc_debug_flags |= SCALABLE_MALLOC_DONT_PROTECT_PRELUDE;
+	    malloc_printf("... but not protecting prelude guard page\n");
+	}
+	if (getenv("MallocDoNotProtectPostlude")) {
+	    malloc_debug_flags |= SCALABLE_MALLOC_DONT_PROTECT_POSTLUDE;
+	    malloc_printf("... but not protecting postlude guard page\n");
+	}
+    }
+    flag = getenv("MallocStackLogging");
+    if (!flag) {
+	flag = getenv("MallocStackLoggingNoCompact");
+	stack_logging_dontcompact = 1;
+    }
+    if (flag) {
+	unsigned	val = strtoul(flag, NULL, 0);
+	if (val == 1) val = 0;
+	if (val == -1) val = 0;
+	malloc_logger = (val) ? (void *)val : stack_logging_log_stack;
+	stack_logging_enable_logging = 1;
+	if (malloc_logger == stack_logging_log_stack) {
+	    malloc_printf("recording stacks using standard recorder\n");
+	} else {
+	    malloc_printf("recording stacks using recorder %p\n", malloc_logger);
+	}
+	if (stack_logging_dontcompact) malloc_printf("stack logging compaction turned off; VM can increase rapidly\n");
+    }
+    if (getenv("MallocScribble")) {
+	malloc_debug_flags |= SCALABLE_MALLOC_DO_SCRIBBLE;
+	malloc_printf("enabling scribbling to detect mods to free blocks\n");
+    }
+    flag = getenv("MallocCheckHeapStart");
+    if (flag) {
+	malloc_check_start = strtoul(flag, NULL, 0);
+	if (malloc_check_start == 0) malloc_check_start = 1;
+	if (malloc_check_start == -1) malloc_check_start = 1;
+	flag = getenv("MallocCheckHeapEach");
+	if (flag) {
+	    malloc_check_each = strtoul(flag, NULL, 0);
+	    if (malloc_check_each == 0) malloc_check_each = 1;
+	    if (malloc_check_each == -1) malloc_check_each = 1;
+	}
+	malloc_printf("checks heap after %dth operation and each %d operations\n", malloc_check_start, malloc_check_each);
+	flag = getenv("MallocCheckHeapAbort");
+	if (flag)
+	    malloc_check_abort = strtol(flag, NULL, 0);
+	if (malloc_check_abort)
+	    malloc_printf("will abort on heap corruption\n");
+	else {
+	    flag = getenv("MallocCheckHeapSleep");
+	    if (flag)
+		malloc_check_sleep = strtol(flag, NULL, 0);
+	    if (malloc_check_sleep > 0)
+		malloc_printf("will sleep for %d seconds on heap corruption\n", malloc_check_sleep);
+	    else if (malloc_check_sleep < 0)
+		malloc_printf("will sleep once for %d seconds on heap corruption\n", -malloc_check_sleep);
+	    else
+		malloc_printf("no sleep on heap corruption\n");
+	}
+    }
+    flag = getenv("MallocBadFreeAbort");
+    if (flag)
+	malloc_free_abort = strtol(flag, NULL, 0);
+    if (getenv("MallocHelp")) {
+	malloc_printf(
+	    "environment variables that can be set for debug:\n"
+	    "- MallocLogFile <f> to create/append messages to file <f> instead of stderr\n"
+	    "- MallocGuardEdges to add 2 guard pages for each large block\n"
+	    "- MallocDoNotProtectPrelude to disable protection (when previous flag set)\n"
+	    "- MallocDoNotProtectPostlude to disable protection (when previous flag set)\n"
+	    "- MallocStackLogging to record all stacks.  Tools like leaks can then be applied\n"
+	    "- MallocStackLoggingNoCompact to record all stacks.  Needed for malloc_history\n"
+	    "- MallocScribble to detect writing on free blocks and missing initializers:\n"
+	    "  0x55 is written upon free and 0xaa is written on allocation\n"
+	    "- MallocCheckHeapStart <n> to start checking the heap after <n> operations\n"
+	    "- MallocCheckHeapEach <s> to repeat the checking of the heap after <s> operations\n"
+	    "- MallocCheckHeapSleep <t> to sleep <t> seconds on heap corruption\n"
+	    "- MallocCheckHeapAbort <b> to abort on heap corruption if <b> is non-zero\n"
+	    "- MallocBadFreeAbort <b> to abort on a bad free if <b> is non-zero\n"
+	    "- MallocHelp - this help!\n");
+    }
+}
+
+malloc_zone_t *
+malloc_create_zone(vm_size_t start_size, unsigned flags) {
+    malloc_zone_t	*zone;
+    if (!malloc_num_zones) {
+	char	**env = * _NSGetEnviron();
+	char	**p;
+	char	*c;
+	/* Given that all environment variables start with "Malloc" we optimize by scanning quickly first the environment, therefore avoiding repeated calls to getenv() */
+	malloc_debug_file = STDERR_FILENO;
+	for (p = env; (c = *p) != NULL; ++p) {
+	    if (!strncmp(c, "Malloc", 6)) {
+		set_flags_from_environment(); 
+		break;
+	    }
+	}
+
+    }
+    zone = create_scalable_zone(start_size, malloc_debug_flags);
+    malloc_zone_register(zone);
+    return zone;
+}
+
+void
+malloc_destroy_zone(malloc_zone_t *zone) {
+    malloc_zone_unregister(zone);
+    zone->destroy(zone);
+}
+
+/*********	Block creation and manipulation	************/
+
+static void
+internal_check(void) {
+    static vm_address_t	*frames = NULL;
+    static unsigned	num_frames;
+    if (malloc_zone_check(NULL)) {
+	malloc_printf("MallocCheckHeap: PASSED check at %dth operation\n", malloc_check_counter-1);
+	if (!frames) vm_allocate(mach_task_self(), (void *)&frames, vm_page_size, 1);
+	thread_stack_pcs(frames, vm_page_size/sizeof(vm_address_t) - 1, &num_frames);
+    } else {
+	malloc_printf("*** MallocCheckHeap: FAILED check at %dth operation\n", malloc_check_counter-1);
+	if (frames) {
+	    unsigned	index = 1;
+	    malloc_printf("Stack for last operation where the malloc check succeeded: ");
+	    while (index < num_frames) malloc_printf("%p ", frames[index++]);
+	    malloc_printf("\n(Use 'atos' for a symbolic stack)\n");
+	}
+	if (malloc_check_each > 1) {
+	    unsigned	recomm_each = (malloc_check_each > 10) ? malloc_check_each/10 : 1;
+	    unsigned	recomm_start = (malloc_check_counter > malloc_check_each+1) ? malloc_check_counter-1-malloc_check_each : 1;
+	    malloc_printf("*** Recommend using 'setenv MallocCheckHeapStart %d; setenv MallocCheckHeapEach %d' to narrow down failure\n", recomm_start, recomm_each);
+	}
+	if (malloc_check_abort)
+	    abort();
+	if (malloc_check_sleep > 0) {
+	    malloc_printf("*** Sleeping for %d seconds to leave time to attach\n",
+		malloc_check_sleep);
+	    sleep(malloc_check_sleep);
+	} else if (malloc_check_sleep < 0) {
+	    malloc_printf("*** Sleeping once for %d seconds to leave time to attach\n",
+		-malloc_check_sleep);
+	    sleep(-malloc_check_sleep);
+	    malloc_check_sleep = 0;
+	}
+    }
+    malloc_check_start += malloc_check_each;
+}
+
+void *
+malloc_zone_malloc(malloc_zone_t *zone, size_t size) {
+    void	*ptr;
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    ptr = zone->malloc(zone, size);
+    if (malloc_logger) malloc_logger(MALLOC_LOG_TYPE_ALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, size, 0, (unsigned)ptr, 0);
+    return ptr;
+}
+
+void *
+malloc_zone_calloc(malloc_zone_t *zone, size_t num_items, size_t size) {
+    void	*ptr;
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    ptr = zone->calloc(zone, num_items, size);
+    if (malloc_logger) malloc_logger(MALLOC_LOG_TYPE_ALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE | MALLOC_LOG_TYPE_CLEARED, (unsigned)zone, num_items * size, 0, (unsigned)ptr, 0);
+    return ptr;
+}
+
+void *
+malloc_zone_valloc(malloc_zone_t *zone, size_t size) {
+    void	*ptr;
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    ptr = zone->valloc(zone, size);
+    if (malloc_logger) malloc_logger(MALLOC_LOG_TYPE_ALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, size, 0, (unsigned)ptr, 0);
+    return ptr;
+}
+
+void *
+malloc_zone_realloc(malloc_zone_t *zone, void *ptr, size_t size) {
+    void	*new_ptr;
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    new_ptr = zone->realloc(zone, ptr, size);
+    if (malloc_logger) malloc_logger(MALLOC_LOG_TYPE_ALLOCATE | MALLOC_LOG_TYPE_DEALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, (unsigned)ptr, size, (unsigned)new_ptr, 0);
+    return new_ptr;
+}
+
+void
+malloc_zone_free(malloc_zone_t *zone, void *ptr) {
+    if (malloc_logger) malloc_logger(MALLOC_LOG_TYPE_DEALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, (unsigned)ptr, 0, 0, 0);
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    zone->free(zone, ptr);
+}
+
+malloc_zone_t *
+malloc_zone_from_ptr(const void *ptr) {
+    malloc_zone_t	*zone;
+    if (!ptr) return NULL;
+    zone = find_registered_zone(ptr, NULL);
+    return zone;
+}
+
+/*********	Functions for zone implementors	************/
+
+void
+malloc_zone_register(malloc_zone_t *zone) {
+    /* Note that given the sequencing it is always safe to first get the number of zones, then get malloc_zones without taking the lock, if all you need is to iterate through the list */
+    MALLOC_LOCK();
+    if (malloc_num_zones >= INITIAL_ZONES) {
+        malloc_zone_t		**zones = malloc_zones;
+        malloc_zone_t		*pzone = malloc_zones[0];
+        boolean_t		copy = malloc_num_zones == INITIAL_ZONES;
+        if (copy) zones = NULL; // to avoid realloc on something not allocated
+        MALLOC_UNLOCK();
+        zones = pzone->realloc(pzone, zones, (malloc_num_zones + 1) * sizeof(malloc_zone_t *)); // we leak initial_malloc_zones, not worth tracking it
+        MALLOC_LOCK();
+        if (copy) memcpy(zones, malloc_zones, malloc_num_zones * sizeof(malloc_zone_t *));
+        malloc_zones = zones;
+    }
+    malloc_zones[malloc_num_zones] = zone;
+    malloc_num_zones++; // note that we do this after setting malloc_num_zones, so enumerations without taking the lock are safe
+    MALLOC_UNLOCK();
+    // malloc_printf("Registered %p malloc_zones at address %p is %p [%d zones]\n", zone, &malloc_zones, malloc_zones, malloc_num_zones);
+}
+
+void
+malloc_zone_unregister(malloc_zone_t *z) {
+    unsigned	index;
+    MALLOC_LOCK();
+    index = malloc_num_zones;
+    while (index--) {
+        malloc_zone_t	*zone = malloc_zones[index];
+        if (zone == z) {
+            malloc_zones[index] = malloc_zones[--malloc_num_zones];
+            MALLOC_UNLOCK();
+            return;
+        }
+    }
+    MALLOC_UNLOCK();
+    malloc_printf("*** malloc_zone_unregister() failed for %p\n", z);
+}
+
+void
+malloc_set_zone_name(malloc_zone_t *z, const char *name) {
+    char	*newName;
+    if (z->zone_name) {
+        free((char *)z->zone_name);
+        z->zone_name = NULL;
+    }
+    newName = malloc_zone_malloc(z, strlen(name) + 1);
+    strcpy(newName, name);
+    z->zone_name = (const char *)newName;
+}
+
+const char *
+malloc_get_zone_name(malloc_zone_t *zone) {
+    return zone->zone_name;
+}
+
+/*
+ * XXX malloc_printf now uses _simple_{,v}dprintf.  It only deals with a
+ * subset of printf format specifiers, but it doesn't call malloc.
+ */
+void _simple_dprintf(int, const char *, ...);
+void _simple_vdprintf(int, const char *, va_list);
+
+void
+malloc_printf(const char *format, ...)
+{
+    va_list ap;
+
+    if (__is_threaded) {
+	/* XXX somewhat rude 'knowing' that pthread_t is a pointer */
+	_simple_dprintf(malloc_debug_file, "%s(%d,%p) malloc: ", getprogname(), getpid(), (void *)pthread_self());
+    } else {
+	_simple_dprintf(malloc_debug_file, "%s(%d) malloc: ", getprogname(), getpid());
+    }
+    va_start(ap, format);
+    _simple_vdprintf(malloc_debug_file, format, ap);
+    va_end(ap);
+}
+
+/*********	Generic ANSI callouts	************/
+
+void *
+malloc(size_t size) {
+    void	*retval;
+    retval = malloc_zone_malloc(inline_malloc_default_zone(), size);
+    if (retval == NULL) {
+	errno = ENOMEM;
+    }
+    return retval;
+}
+
+void *
+calloc(size_t num_items, size_t size) {
+    void	*retval;
+    retval = malloc_zone_calloc(inline_malloc_default_zone(), num_items, size);
+    if (retval == NULL) {
+	errno = ENOMEM;
+    }
+    return retval;
+}
+
+void
+free(void *ptr) {
+    malloc_zone_t	*zone;
+    if (!ptr) return;
+    zone = find_registered_zone(ptr, NULL);
+    if (zone) {
+        malloc_zone_free(zone, ptr);
+    } else {
+        malloc_printf("***  Deallocation of a pointer not malloced: %p; "
+	  "This could be a double free(), or free() called with the middle of an allocated block; "
+	  "Try setting environment variable MallocHelp to see tools to help debug\n", ptr);
+	if (malloc_free_abort)
+	    abort();
+    }
+}
+
+void *
+realloc(void *old_ptr, size_t new_size) {
+    void	*retval;
+    malloc_zone_t	*zone;
+    size_t	old_size = 0;
+    if (!old_ptr) {
+	retval = malloc_zone_malloc(inline_malloc_default_zone(), new_size);
+    } else {
+	zone = find_registered_zone(old_ptr, &old_size);
+	if (zone && (old_size >= new_size)) return old_ptr;
+	if (!zone) zone = inline_malloc_default_zone();
+	retval = malloc_zone_realloc(zone, old_ptr, new_size);
+    }
+    if (retval == NULL) {
+	errno = ENOMEM;
+    }
+    return retval;
+}
+
+void *
+valloc(size_t size) {
+    void	*retval;
+    malloc_zone_t	*zone = inline_malloc_default_zone();
+    retval = malloc_zone_valloc(zone, size);
+    if (retval == NULL) {
+	errno = ENOMEM;
+    }
+    return retval;
+}
+
+extern void
+vfree(void *ptr) {
+    free(ptr);
+}
+
+size_t
+malloc_size(const void *ptr) {
+    size_t	size = 0;
+    if (!ptr) return size;
+    (void)find_registered_zone(ptr, &size);
+    return size;
+}
+
+size_t
+malloc_good_size (size_t size) {
+    malloc_zone_t	*zone = inline_malloc_default_zone();
+    return zone->introspect->good_size(zone, size);
+}
+
+/*********	Batch methods	************/
+
+unsigned
+malloc_zone_batch_malloc(malloc_zone_t *zone, size_t size, void **results, unsigned num_requested) {
+    unsigned	(*batch_malloc)(malloc_zone_t *, size_t, void **, unsigned) = zone-> batch_malloc;
+    if (! batch_malloc) return 0;
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    unsigned	batched = batch_malloc(zone, size, results, num_requested);
+    if (malloc_logger) {
+	unsigned	index = 0;
+	while (index < batched) {
+	    malloc_logger(MALLOC_LOG_TYPE_ALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, size, 0, (unsigned)results[index], 0);
+	    index++;
+	}
+    }
+    return batched;
+}
+
+void
+malloc_zone_batch_free(malloc_zone_t *zone, void **to_be_freed, unsigned num) {
+    if (malloc_check_start && (malloc_check_counter++ >= malloc_check_start)) {
+	internal_check();
+    }
+    if (malloc_logger) {
+	unsigned	index = 0;
+	while (index < num) {
+	    malloc_logger(MALLOC_LOG_TYPE_DEALLOCATE | MALLOC_LOG_TYPE_HAS_ZONE, (unsigned)zone, (unsigned)to_be_freed[index], 0, 0, 0);
+	    index++;
+	}
+    }
+    void	(*batch_free)(malloc_zone_t *, void **, unsigned) = zone-> batch_free;
+    if (batch_free) {
+	batch_free(zone, to_be_freed, num);
+    } else {
+	void 	(*free_fun)(malloc_zone_t *, void *) = zone->free;
+	while (num--) {
+	    void	*ptr = *to_be_freed++;
+	    free_fun(zone, ptr);
+	}
+    }
+}
+
+/*********	Functions for performance tools	************/
+
+static kern_return_t
+_malloc_default_reader(task_t task, vm_address_t address, vm_size_t size, void **ptr) {
+    *ptr = (void *)address;
+    return 0;
+}
+
+kern_return_t
+malloc_get_all_zones(task_t task, memory_reader_t reader, vm_address_t **addresses, unsigned *count) {
+    // Note that the 2 following addresses are not correct if the address of the target is different from your own.  This notably occurs if the address of System.framework is slid (e.g. different than at B & I )
+    vm_address_t	remote_malloc_zones = (vm_address_t)&malloc_zones;
+    vm_address_t	remote_malloc_num_zones = (vm_address_t)&malloc_num_zones;
+    kern_return_t	err;
+    vm_address_t	zones_address;
+    vm_address_t	*zones_address_ref;
+    unsigned		num_zones;
+    unsigned		*num_zones_ref;
+    if (!reader) reader = _malloc_default_reader;
+    // printf("Read malloc_zones at address %p should be %p\n", &malloc_zones, malloc_zones);
+    err = reader(task, remote_malloc_zones, sizeof(void *), (void **)&zones_address_ref);
+    // printf("Read malloc_zones[%p]=%p\n", remote_malloc_zones, *zones_address_ref);
+    if (err) {
+        malloc_printf("*** malloc_get_all_zones: error reading zones_address at %p\n", (unsigned)remote_malloc_zones);
+        return err;
+    }
+    zones_address = *zones_address_ref;
+    // printf("Reading num_zones at address %p\n", remote_malloc_num_zones);
+    err = reader(task, remote_malloc_num_zones, sizeof(unsigned), (void **)&num_zones_ref);
+    if (err) {
+        malloc_printf("*** malloc_get_all_zones: error reading num_zones at %p\n", (unsigned)remote_malloc_num_zones);
+        return err;
+    }
+    num_zones = *num_zones_ref;
+    // printf("Read malloc_num_zones[%p]=%d\n", remote_malloc_num_zones, num_zones);
+    *count = num_zones;
+    // printf("malloc_get_all_zones succesfully found %d zones\n", num_zones);
+    err = reader(task, zones_address, sizeof(malloc_zone_t *) * num_zones, (void **)addresses);
+    if (err) {
+        malloc_printf("*** malloc_get_all_zones: error reading zones at %p\n", (unsigned)&zones_address);
+        return err;
+    }
+    // printf("malloc_get_all_zones succesfully read %d zones\n", num_zones);
+    return err;
+}
+
+/*********	Debug helpers	************/
+
+void
+malloc_zone_print_ptr_info(void *ptr) {
+    malloc_zone_t	*zone;
+    if (!ptr) return;
+    zone = find_registered_zone(ptr, NULL);
+    if (zone) {
+        printf("ptr %p in registered zone %p\n", ptr, zone);
+    } else {
+        printf("ptr %p not in heap\n", ptr);
+    }
+}
+
+boolean_t
+malloc_zone_check(malloc_zone_t *zone) {
+    boolean_t	ok = 1;
+    if (!zone) {
+        unsigned	index = 0;
+        while (index < malloc_num_zones) {
+            zone = malloc_zones[index++];
+            if (!zone->introspect->check(zone)) ok = 0;
+        }
+    } else {
+        ok = zone->introspect->check(zone);
+    }
+    return ok;
+}
+
+void
+malloc_zone_print(malloc_zone_t *zone, boolean_t verbose) {
+    if (!zone) {
+        unsigned	index = 0;
+        while (index < malloc_num_zones) {
+            zone = malloc_zones[index++];
+            zone->introspect->print(zone, verbose);
+        }
+    } else {
+        zone->introspect->print(zone, verbose);
+    }
+}
+
+void
+malloc_zone_statistics(malloc_zone_t *zone, malloc_statistics_t *stats) {
+    if (!zone) {
+	memset(stats, 0, sizeof(stats));
+        unsigned	index = 0;
+        while (index < malloc_num_zones) {
+            zone = malloc_zones[index++];
+	    malloc_statistics_t	this_stats;
+            zone->introspect->statistics(zone, &this_stats);
+	    stats->blocks_in_use += this_stats.blocks_in_use;
+	    stats->size_in_use += this_stats.size_in_use;
+	    stats->max_size_in_use += this_stats.max_size_in_use;
+	    stats->size_allocated += this_stats.size_allocated;
+        }
+    } else {
+	zone->introspect->statistics(zone, stats);
+    }
+}
+
+void
+malloc_zone_log(malloc_zone_t *zone, void *address) {
+    if (!zone) {
+        unsigned	index = 0;
+        while (index < malloc_num_zones) {
+            zone = malloc_zones[index++];
+            zone->introspect->log(zone, address);
+        }
+    } else {
+        zone->introspect->log(zone, address);
+    }
+}
+
+/*********	Misc other entry points	************/
+
+static void
+DefaultMallocError(int x) {
+    malloc_printf("*** error %d\n", x);
+#if USE_SLEEP_RATHER_THAN_ABORT
+    sleep(3600);
+#else
+    abort();
+#endif
+}
+
+void (*
+malloc_error(void (*func)(int)))(int) {
+    return DefaultMallocError;
+}
+
+void
+_malloc_fork_prepare() {
+    /* Prepare the malloc module for a fork by insuring that no thread is in a malloc critical section */
+    unsigned	index = 0;
+    MALLOC_LOCK();
+    while (index < malloc_num_zones) {
+        malloc_zone_t	*zone = malloc_zones[index++];
+        zone->introspect->force_lock(zone);
+    }
+}
+
+void
+_malloc_fork_parent() {
+    /* Called in the parent process after a fork() to resume normal operation. */
+    unsigned	index = 0;
+    MALLOC_UNLOCK();
+    while (index < malloc_num_zones) {
+        malloc_zone_t	*zone = malloc_zones[index++];
+        zone->introspect->force_unlock(zone);
+    }
+}
+
+void
+_malloc_fork_child() {
+    /* Called in the child process after a fork() to resume normal operation.  In the MTASK case we also have to change memory inheritance so that the child does not share memory with the parent. */
+    unsigned	index = 0;
+    MALLOC_UNLOCK();
+    while (index < malloc_num_zones) {
+        malloc_zone_t	*zone = malloc_zones[index++];
+        zone->introspect->force_unlock(zone);
+    }
+}
+
+/*
+ * A Glibc-like mstats() interface.
+ *
+ * Note that this interface really isn't very good, as it doesn't understand
+ * that we may have multiple allocators running at once.  We just massage
+ * the result from malloc_zone_statistics in any case.
+ */
+struct mstats
+mstats(void)
+{
+    malloc_statistics_t s;
+    struct mstats m;
+
+    malloc_zone_statistics(NULL, &s);
+    m.bytes_total = s.size_allocated;
+    m.chunks_used = s.blocks_in_use;
+    m.bytes_used = s.size_in_use;
+    m.chunks_free = 0;
+    m.bytes_free = m.bytes_total - m.bytes_used;	/* isn't this somewhat obvious? */
+
+    return(m);
+}
+
+/*****************	OBSOLETE ENTRY POINTS	********************/
+
+#if PHASE_OUT_OLD_MALLOC
+#error PHASE OUT THE FOLLOWING FUNCTIONS
+#else
+#warning PHASE OUT THE FOLLOWING FUNCTIONS
+#endif
+
+void
+set_malloc_singlethreaded(boolean_t single) {
+    static boolean_t warned = 0;
+    if (!warned) {
+#if PHASE_OUT_OLD_MALLOC
+        malloc_printf("*** OBSOLETE: set_malloc_singlethreaded(%d)\n", single);
+#endif
+        warned = 1;
+    }
+}
+
+void
+malloc_singlethreaded() {
+    static boolean_t warned = 0;
+    if (!warned) {
+        malloc_printf("*** OBSOLETE: malloc_singlethreaded()\n");
+        warned = 1;
+    }
+}
+
+int
+malloc_debug(int level) {
+    malloc_printf("*** OBSOLETE: malloc_debug()\n");
+    return 0;
+}