Proposing ZendMM Observer API

Zend/zend_alloc.h

@@ -268,9 +268,10 @@ ZEND_API zend_mm_heap *zend_mm_get_heap(void);
 
 ZEND_API size_t zend_mm_gc(zend_mm_heap *heap);
 
-#define ZEND_MM_CUSTOM_HEAP_NONE  0
-#define ZEND_MM_CUSTOM_HEAP_STD   1
-#define ZEND_MM_CUSTOM_HEAP_DEBUG 2
+#define ZEND_MM_CUSTOM_HEAP_NONE     0
+#define ZEND_MM_CUSTOM_HEAP_STD      1
+#define ZEND_MM_CUSTOM_HEAP_DEBUG    2
+#define ZEND_MM_CUSTOM_HEAP_OBSERVED 4
 
 ZEND_API bool zend_mm_is_custom_heap(zend_mm_heap *new_heap);
 ZEND_API void zend_mm_set_custom_handlers(zend_mm_heap *heap,
@@ -294,6 +295,19 @@ ZEND_API void zend_mm_get_custom_handlers_ex(zend_mm_heap *heap,
                                           size_t (**_gc)(void),
                                           void   (**_shutdown)(bool, bool));
 
+typedef struct _zend_mm_observer zend_mm_observer;
+
+ZEND_API bool zend_mm_is_observed(zend_mm_heap *heap);
+ZEND_API zend_mm_observer* zend_mm_observer_register(
+	zend_mm_heap *heap,
+	void (*malloc)(size_t len, void *ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+	void (*free)(void *ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+	void (*realloc)(void *old_ptr, size_t len, void *new_ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC),
+	void (*gc)(size_t len),
+	void (*shutdown)(bool full, bool silent)
+);
+ZEND_API bool zend_mm_observer_unregister(zend_mm_heap *heap, zend_mm_observer *observer);
+
 typedef struct _zend_mm_storage zend_mm_storage;
 
 typedef	void* (*zend_mm_chunk_alloc_t)(zend_mm_storage *storage, size_t size, size_t alignment);

ext/zend_test/config.m4

@@ -11,6 +11,7 @@ if test "$PHP_ZEND_TEST" != "no"; then
       observer.c
       test.c
       zend_mm_custom_handlers.c
+      zend_mm_observer.c
     ]),
     [$ext_shared],,
     [-DZEND_ENABLE_STATIC_TSRMLS_CACHE=1])

ext/zend_test/config.w32

@@ -3,5 +3,6 @@
 ARG_ENABLE("zend-test", "enable zend_test extension", "no");
 
 if (PHP_ZEND_TEST != "no") {
-	EXTENSION("zend_test", "test.c observer.c fiber.c iterators.c object_handlers.c zend_mm_custom_handlers.c", PHP_ZEND_TEST_SHARED, "/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1");
+	EXTENSION("zend_test", "test.c observer.c fiber.c iterators.c object_handlers.c zend_mm_custom_handlers.c zend_mm_observer.c", PHP_ZEND_TEST_SHARED, "/DZEND_ENABLE_STATIC_TSRMLS_CACHE=1");
+	ADD_FLAG("CFLAGS_ZEND_TEST", "/D PHP_ZEND_TEST_EXPORTS ");
 }

ext/zend_test/php_test.h

@@ -14,6 +14,7 @@
 #define PHP_TEST_H
 
 #include "fiber.h"
+#include "Zend/zend_alloc.h"
 
 extern zend_module_entry zend_test_module_entry;
 #define phpext_zend_test_ptr &zend_test_module_entry
@@ -71,6 +72,8 @@ ZEND_BEGIN_MODULE_GLOBALS(zend_test)
 	// this is our heap that we install our custom handlers on and inject into
 	// ZendMM
 	zend_mm_heap* observed_heap;
+	int zend_mm_observer_enabled;
+	zend_mm_observer *observer;
 ZEND_END_MODULE_GLOBALS(zend_test)
 
 extern ZEND_DECLARE_MODULE_GLOBALS(zend_test)

ext/zend_test/test.c

@@ -23,6 +23,7 @@
 #include "ext/standard/info.h"
 #include "php_test.h"
 #include "observer.h"
+#include "zend_mm_observer.h"
 #include "fiber.h"
 #include "iterators.h"
 #include "object_handlers.h"
@@ -1602,6 +1603,7 @@ PHP_MINIT_FUNCTION(zend_test)
 
 	zend_test_observer_init(INIT_FUNC_ARGS_PASSTHRU);
 	zend_test_mm_custom_handlers_minit(INIT_FUNC_ARGS_PASSTHRU);
+	zend_test_mm_observer_minit(INIT_FUNC_ARGS_PASSTHRU);
 	zend_test_fiber_init();
 	zend_test_iterators_init();
 	zend_test_object_handlers_init();
@@ -1632,6 +1634,7 @@ PHP_RINIT_FUNCTION(zend_test)
 	zend_hash_init(ZT_G(global_weakmap), 8, NULL, ZVAL_PTR_DTOR, 0);
 	ZT_G(observer_nesting_depth) = 0;
 	zend_test_mm_custom_handlers_rinit();
+	zend_test_mm_observer_rinit();
 	return SUCCESS;
 }
 
@@ -1647,6 +1650,7 @@ PHP_RSHUTDOWN_FUNCTION(zend_test)
 	}
 
 	zend_test_mm_custom_handlers_rshutdown();
+	zend_test_mm_observer_rshutdown();
 	return SUCCESS;
 }
 

ext/zend_test/tests/zend_mm_observer_free_01.phpt

@@ -0,0 +1,16 @@
+--TEST--
+ZendMM Observer: Observe free
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.zend_mm_observer.enabled=0
+opcache.enable=0
+--FILE--
+<?php
+$string = str_repeat("ZendMM Observer", 100);
+ini_set('zend_test.zend_mm_observer.enabled', 'true');
+unset($string);
+ini_set('zend_test.zend_mm_observer.enabled', 'false');
+?>
+--EXPECTREGEX--
+.*freed \S+ of size \d+.*

ext/zend_test/tests/zend_mm_observer_gc_01.phpt

@@ -0,0 +1,15 @@
+--TEST--
+ZendMM Observer: Observe garbage collection
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.zend_mm_observer.enabled=0
+opcache.enable=0
+--FILE--
+<?php
+ini_set('zend_test.zend_mm_observer.enabled', 'true');
+gc_mem_caches();
+ini_set('zend_test.zend_mm_observer.enabled', 'false');
+?>
+--EXPECTREGEX--
+.*garbage collection ended with \d+ bytes collected.*

ext/zend_test/tests/zend_mm_observer_lifecycle_01.phpt

@@ -0,0 +1,13 @@
+--TEST--
+ZendMM Observer: Observe lifecycle (RINIT -> RSHUTDOWN)
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.zend_mm_observer.enabled=1
+opcache.enable=0
+--FILE--
+<?php
+echo "done";
+?>
+--EXPECTREGEX--
+.*ZendMM Observer enabled.*

ext/zend_test/tests/zend_mm_observer_malloc_01.phpt

@@ -0,0 +1,15 @@
+--TEST--
+ZendMM Observer: Observe malloc
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.zend_mm_observer.enabled=0
+opcache.enable=0
+--FILE--
+<?php
+ini_set('zend_test.zend_mm_observer.enabled', 'true');
+$string = str_repeat("ZendMM Observer", 100);
+ini_set('zend_test.zend_mm_observer.enabled', 'false');
+?>
+--EXPECTREGEX--
+.*malloc \S+ of size \d+ \(block: \d+\).*

ext/zend_test/tests/zend_mm_observer_realloc_01.phpt

@@ -0,0 +1,26 @@
+--TEST--
+ZendMM Observer: Observe realloc
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.zend_mm_observer.enabled=0
+opcache.enable=0
+--FILE--
+<?php
+$a = [];
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+$a[] = 'ZendMM Observer';
+ini_set('zend_test.zend_mm_observer.enabled', 'true');
+$a[] = 'ZendMM Observer';
+ini_set('zend_test.zend_mm_observer.enabled', 'false');
+?>
+--EXPECTREGEX--
+.*ZendMM Observer enabled.*
+.*realloc \S+ of size \d+ \(block: \d+, former \S+\).*
+.*ZendMM Observer disabled.*

ext/zend_test/tests/zend_mm_observer_shutdown_01.phpt

@@ -0,0 +1,14 @@
+--TEST--
+ZendMM Observer: Observe shutdown
+--EXTENSIONS--
+zend_test
+--ENV--
+ZEND_TEST_MM_OBSERVER_SHUTDOWN_TEST=1
+--INI--
+zend_test.zend_mm_observer.enabled=1
+--FILE--
+<?php
+echo "done.";
+?>
+--EXPECTREGEX--
+.*shutdown in progress: full\(\d\), silent\(\d\).*

ext/zend_test/zend_mm_observer.c

@@ -0,0 +1,143 @@
+/*
+  +----------------------------------------------------------------------+
+  | Copyright (c) The PHP Group                                          |
+  +----------------------------------------------------------------------+
+  | This source file is subject to version 3.01 of the PHP license,      |
+  | that is bundled with this package in the file LICENSE, and is        |
+  | available through the world-wide-web at the following url:           |
+  | https://www.php.net/license/3_01.txt                                 |
+  | If you did not receive a copy of the PHP license and are unable to   |
+  | obtain it through the world-wide-web, please send a note to          |
+  | license@php.net so we can mail you a copy immediately.               |
+  +----------------------------------------------------------------------+
+  | Author: Florian Engelhardt <florian@engelhardt.tc>                   |
+  +----------------------------------------------------------------------+
+*/
+
+#include "php.h"
+#include "php_test.h"
+#include "Zend/zend_alloc.h"
+#include "ext/standard/info.h"
+#include "ext/standard/php_var.h"
+#include "zend_mm_observer.h"
+
+static void zend_mm_test_observer_malloc(size_t len, void *ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+{
+	size_t block_len = 0;
+	if (is_zend_ptr(ptr)) {
+		block_len = zend_mm_block_size(zend_mm_get_heap(), ptr);
+	}
+	printf("malloc %p of size %zu (block: %zu)\n", ptr, len, block_len);
+	fflush(stdout);
+}
+
+static void zend_mm_test_observer_free(void *ptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+{
+	size_t block_len = 0;
+	if (is_zend_ptr(ptr)) {
+		block_len = zend_mm_block_size(zend_mm_get_heap(), ptr);
+	}
+	printf("freed %p of size %zu\n", ptr, block_len);
+	fflush(stdout);
+}
+
+static void zend_mm_test_observer_realloc(void *ptr, size_t len, void *newptr ZEND_FILE_LINE_DC ZEND_FILE_LINE_ORIG_DC)
+{
+	size_t block_len = 0;
+	if (is_zend_ptr(ptr)) {
+		block_len = zend_mm_block_size(zend_mm_get_heap(), ptr);
+	}
+	printf("realloc %p of size %zu (block: %zu, former %p)\n", newptr, len, block_len, ptr);
+	fflush(stdout);
+}
+
+static void zend_mm_test_observer_gc(size_t len)
+{
+	printf("garbage collection ended with %zu bytes collected\n", len);
+	fflush(stdout);
+}
+
+static void zend_mm_test_observer_shutdown(bool full, bool silent)
+{
+	printf("shutdown in progress: full(%d), silent(%d)\n", full, silent);
+	fflush(stdout);
+}
+
+static PHP_INI_MH(OnUpdateZendTestMMObserverEnabled)
+{
+	if (new_value == NULL) {
+		return FAILURE;
+	}
+
+	int int_value = zend_ini_parse_bool(new_value);
+
+	/* Only toggle observer during runtime (ini_set during active request).
+	 * RINIT/RSHUTDOWN handle initialization and cleanup. */
+	if (stage == PHP_INI_STAGE_RUNTIME) {
+		if (int_value == 1) {
+			if (ZT_G(observer) == NULL) {
+				ZT_G(observer) = zend_mm_observer_register(
+					zend_mm_get_heap(),
+					zend_mm_test_observer_malloc,
+					zend_mm_test_observer_free,
+					zend_mm_test_observer_realloc,
+					zend_mm_test_observer_gc,
+					zend_mm_test_observer_shutdown
+				);
+				printf("ZendMM Observer enabled\n");
+				fflush(stdout);
+			}
+		} else {
+			if (ZT_G(observer) != NULL) {
+				zend_mm_observer_unregister(zend_mm_get_heap(), ZT_G(observer));
+				ZT_G(observer) = NULL;
+				printf("ZendMM Observer disabled\n");
+				fflush(stdout);
+			}
+		}
+	}
+	return OnUpdateBool(entry, new_value, mh_arg1, mh_arg2, mh_arg3, stage);
+}
+
+PHP_INI_BEGIN()
+	STD_PHP_INI_BOOLEAN("zend_test.zend_mm_observer.enabled", "0", PHP_INI_ALL, OnUpdateZendTestMMObserverEnabled, zend_mm_observer_enabled, zend_zend_test_globals, zend_test_globals)
+PHP_INI_END()
+
+void zend_test_mm_observer_minit(INIT_FUNC_ARGS)
+{
+	if (type != MODULE_TEMPORARY) {
+		REGISTER_INI_ENTRIES();
+	} else {
+		(void)ini_entries;
+	}
+}
+
+void zend_test_mm_observer_rinit(void)
+{
+	if (ZT_G(zend_mm_observer_enabled)) {
+		ZT_G(observer) = zend_mm_observer_register(
+			zend_mm_get_heap(),
+			zend_mm_test_observer_malloc,
+			zend_mm_test_observer_free,
+			zend_mm_test_observer_realloc,
+			zend_mm_test_observer_gc,
+			zend_mm_test_observer_shutdown
+		);
+		printf("ZendMM Observer enabled\n");
+		fflush(stdout);
+	}
+}
+
+void zend_test_mm_observer_rshutdown(void)
+{
+	char *env = getenv("ZEND_TEST_MM_OBSERVER_SHUTDOWN_TEST");
+	if (env != NULL) {
+		return;
+	}
+	if (ZT_G(observer)) {
+		zend_mm_observer_unregister(zend_mm_get_heap(), ZT_G(observer));
+		printf("ZendMM Observer disabled\n");
+		fflush(stdout);
+	}
+	ZT_G(observer) = NULL;
+}

ext/zend_test/zend_mm_observer.h

@@ -0,0 +1,24 @@
+/*
+  +----------------------------------------------------------------------+
+  | Copyright (c) The PHP Group                                          |
+  +----------------------------------------------------------------------+
+  | This source file is subject to version 3.01 of the PHP license,      |
+  | that is bundled with this package in the file LICENSE, and is        |
+  | available through the world-wide-web at the following url:           |
+  | https://www.php.net/license/3_01.txt                                 |
+  | If you did not receive a copy of the PHP license and are unable to   |
+  | obtain it through the world-wide-web, please send a note to          |
+  | license@php.net so we can mail you a copy immediately.               |
+  +----------------------------------------------------------------------+
+  | Author: Florian Engelhardt <florian@engelhardt.tc>                   |
+  +----------------------------------------------------------------------+
+*/
+
+#ifndef ZEND_TEST_MM_OBSERVER_H
+#define ZEND_TEST_MM_OBSERVER_H
+
+void zend_test_mm_observer_minit(INIT_FUNC_ARGS);
+void zend_test_mm_observer_rinit(void);
+void zend_test_mm_observer_rshutdown(void);
+
+#endif