Add an API to observe functions and classes being linked

bwoebi · bwoebi · commit bf427b732aba · 2022-08-23T15:22:22.000+02:00
To observe when the functions and classes start being officially available to the user

Signed-off-by: Bob Weinand &lt;bobwei9@hotmail.com&gt;
diff --git a/Zend/zend_API.c b/Zend/zend_API.c
@@ -31,6 +31,7 @@
 #include "zend_inheritance.h"
 #include "zend_ini.h"
 #include "zend_enum.h"
+#include "zend_observer.h"
 
 #include <stdarg.h>
 
@@ -3263,6 +3264,7 @@ ZEND_API zend_result zend_register_class_alias_ex(const char *name, size_t name_
 		if (!(ce->ce_flags & ZEND_ACC_IMMUTABLE)) {
 			ce->refcount++;
 		}
+		zend_observer_class_linked_notify(ce, lcname);
 		return SUCCESS;
 	}
 	return FAILURE;
diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
@@ -1093,6 +1093,7 @@ ZEND_API zend_result do_bind_function(zend_function *func, zval *lcname) /* {{{
 	if (func->common.function_name) {
 		zend_string_addref(func->common.function_name);
 	}
+	zend_observer_function_declared_notify(&func->op_array, Z_STR_P(lcname));
 	return SUCCESS;
 }
 /* }}} */
@@ -1116,12 +1117,14 @@ ZEND_API zend_class_entry *zend_bind_class_in_slot(
 	}
 
 	if (ce->ce_flags & ZEND_ACC_LINKED) {
+		zend_observer_class_linked_notify(ce, Z_STR_P(lcname));
 		return ce;
 	}
 
 	ce = zend_do_link_class(ce, lc_parent_name, Z_STR_P(lcname));
 	if (ce) {
 		ZEND_ASSERT(!EG(exception));
+		zend_observer_class_linked_notify(ce, Z_STR_P(lcname));
 		return ce;
 	}
 
@@ -7245,6 +7248,7 @@ static void zend_begin_func_decl(znode *result, zend_op_array *op_array, zend_as
 		if (UNEXPECTED(zend_hash_add_ptr(CG(function_table), lcname, op_array) == NULL)) {
 			do_bind_function_error(lcname, op_array, 1);
 		}
+		zend_observer_function_declared_notify(op_array, lcname);
 		zend_string_release_ex(lcname, 0);
 		return;
 	}
@@ -7877,6 +7881,7 @@ static void zend_compile_class_decl(znode *result, zend_ast *ast, bool toplevel)
 				zend_string_release(lcname);
 				zend_build_properties_info_table(ce);
 				ce->ce_flags |= ZEND_ACC_LINKED;
+				zend_observer_class_linked_notify(ce, lcname);
 				return;
 			}
 		} else if (!extends_ast) {
diff --git a/Zend/zend_compile.h b/Zend/zend_compile.h
@@ -1181,6 +1181,9 @@ END_EXTERN_C()
 /* this flag is set when compiler invoked during preloading in separate process */
 #define ZEND_COMPILE_PRELOAD_IN_CHILD           (1<<17)
 
+/* ignore observer notifications, e.g. to manually notify afterwards in a post-processing step after compilation */
+#define ZEND_COMPILE_IGNORE_OBSERVER			(1<<18)
+
 /* The default value for CG(compiler_options) */
 #define ZEND_COMPILE_DEFAULT					ZEND_COMPILE_HANDLE_OP_ARRAY
 
diff --git a/Zend/zend_inheritance.c b/Zend/zend_inheritance.c
@@ -29,6 +29,7 @@
 #include "zend_enum.h"
 #include "zend_attributes.h"
 #include "zend_constants.h"
+#include "zend_observer.h"
 
 ZEND_API zend_class_entry* (*zend_inheritance_cache_get)(zend_class_entry *ce, zend_class_entry *parent, zend_class_entry **traits_and_interfaces) = NULL;
 ZEND_API zend_class_entry* (*zend_inheritance_cache_add)(zend_class_entry *ce, zend_class_entry *proto, zend_class_entry *parent, zend_class_entry **traits_and_interfaces, HashTable *dependencies) = NULL;
@@ -3134,18 +3135,24 @@ static zend_always_inline bool register_early_bound_ce(zval *delayed_early_bindi
 		if (EXPECTED(!(ce->ce_flags & ZEND_ACC_PRELOADED))) {
 			if (zend_hash_set_bucket_key(EG(class_table), (Bucket *)delayed_early_binding, lcname) != NULL) {
 				Z_CE_P(delayed_early_binding) = ce;
+				zend_observer_class_linked_notify(ce, lcname);
 				return true;
 			}
 		} else {
 			/* If preloading is used, don't replace the existing bucket, add a new one. */
 			if (zend_hash_add_ptr(EG(class_table), lcname, ce) != NULL) {
+				zend_observer_class_linked_notify(ce, lcname);
 				return true;
 			}
 		}
 		zend_error_noreturn(E_COMPILE_ERROR, "Cannot declare %s %s, because the name is already in use", zend_get_object_type(ce), ZSTR_VAL(ce->name));
 		return false;
 	}
-	return zend_hash_add_ptr(CG(class_table), lcname, ce) != NULL;
+	if (zend_hash_add_ptr(CG(class_table), lcname, ce) != NULL) {
+		zend_observer_class_linked_notify(ce, lcname);
+		return true;
+	}
+	return false;
 }
 
 ZEND_API zend_class_entry *zend_try_early_bind(zend_class_entry *ce, zend_class_entry *parent_ce, zend_string *lcname, zval *delayed_early_binding) /* {{{ */
diff --git a/Zend/zend_observer.c b/Zend/zend_observer.c
@@ -32,12 +32,17 @@
 	(ZEND_MAP_PTR(function->common.run_time_cache) && !(function->common.fn_flags & ZEND_ACC_CALL_VIA_TRAMPOLINE))
 
 zend_llist zend_observers_fcall_list;
+zend_llist zend_observer_function_declared_callbacks;
+zend_llist zend_observer_class_linked_callbacks;
 zend_llist zend_observer_error_callbacks;
 zend_llist zend_observer_fiber_init;
 zend_llist zend_observer_fiber_switch;
 zend_llist zend_observer_fiber_destroy;
 
 int zend_observer_fcall_op_array_extension;
+bool zend_observer_errors_observed;
+bool zend_observer_function_declared_observed;
+bool zend_observer_class_linked_observed;
 
 ZEND_TLS zend_execute_data *current_observed_frame;
 
@@ -51,6 +56,8 @@ ZEND_API void zend_observer_fcall_register(zend_observer_fcall_init init)
 ZEND_API void zend_observer_startup(void)
 {
 	zend_llist_init(&zend_observers_fcall_list, sizeof(zend_observer_fcall_init), NULL, 1);
+	zend_llist_init(&zend_observer_function_declared_callbacks, sizeof(zend_observer_function_declared_cb), NULL, 1);
+	zend_llist_init(&zend_observer_class_linked_callbacks, sizeof(zend_observer_class_linked_cb), NULL, 1);
 	zend_llist_init(&zend_observer_error_callbacks, sizeof(zend_observer_error_cb), NULL, 1);
 	zend_llist_init(&zend_observer_fiber_init, sizeof(zend_observer_fiber_init_handler), NULL, 1);
 	zend_llist_init(&zend_observer_fiber_switch, sizeof(zend_observer_fiber_switch_handler), NULL, 1);
@@ -100,6 +107,8 @@ ZEND_API void zend_observer_activate(void)
 ZEND_API void zend_observer_shutdown(void)
 {
 	zend_llist_destroy(&zend_observers_fcall_list);
+	zend_llist_destroy(&zend_observer_function_declared_callbacks);
+	zend_llist_destroy(&zend_observer_class_linked_callbacks);
 	zend_llist_destroy(&zend_observer_error_callbacks);
 	zend_llist_destroy(&zend_observer_fiber_init);
 	zend_llist_destroy(&zend_observer_fiber_switch);
@@ -286,8 +295,45 @@ ZEND_API void zend_observer_fcall_end_all(void)
 	EG(current_execute_data) = original_execute_data;
 }
 
+ZEND_API void zend_observer_function_declared_register(zend_observer_function_declared_cb cb)
+{
+	zend_observer_function_declared_observed = true;
+	zend_llist_add_element(&zend_observer_function_declared_callbacks, &cb);
+}
+
+ZEND_API void ZEND_FASTCALL zend_observer_function_declared_notify(zend_op_array *op_array, zend_string *name)
+{
+	if (CG(compiler_options) & ZEND_COMPILE_IGNORE_OBSERVER) {
+		return;
+	}
+
+	for (zend_llist_element *element = zend_observer_function_declared_callbacks.head; element; element = element->next) {
+		zend_observer_function_declared_cb callback = *(zend_observer_function_declared_cb *) (element->data);
+		callback(op_array, name);
+	}
+}
+
+ZEND_API void zend_observer_class_linked_register(zend_observer_class_linked_cb cb)
+{
+	zend_observer_class_linked_observed = true;
+	zend_llist_add_element(&zend_observer_class_linked_callbacks, &cb);
+}
+
+ZEND_API void ZEND_FASTCALL zend_observer_class_linked_notify(zend_class_entry *ce, zend_string *name)
+{
+	if (CG(compiler_options) & ZEND_COMPILE_IGNORE_OBSERVER) {
+		return;
+	}
+
+	for (zend_llist_element *element = zend_observer_class_linked_callbacks.head; element; element = element->next) {
+		zend_observer_class_linked_cb callback = *(zend_observer_class_linked_cb *) (element->data);
+		callback(ce, name);
+	}
+}
+
 ZEND_API void zend_observer_error_register(zend_observer_error_cb cb)
 {
+	zend_observer_errors_observed = true;
 	zend_llist_add_element(&zend_observer_error_callbacks, &cb);
 }
 
diff --git a/Zend/zend_observer.h b/Zend/zend_observer.h
@@ -27,6 +27,9 @@
 BEGIN_EXTERN_C()
 
 extern ZEND_API int zend_observer_fcall_op_array_extension;
+extern ZEND_API bool zend_observer_errors_observed;
+extern ZEND_API bool zend_observer_function_declared_observed;
+extern ZEND_API bool zend_observer_class_linked_observed;
 
 #define ZEND_OBSERVER_ENABLED (zend_observer_fcall_op_array_extension != -1)
 
@@ -80,6 +83,14 @@ ZEND_API void ZEND_FASTCALL zend_observer_fcall_end(
 
 ZEND_API void zend_observer_fcall_end_all(void);
 
+typedef void (*zend_observer_function_declared_cb)(zend_op_array *op_array, zend_string *name);
+typedef void (*zend_observer_class_linked_cb)(zend_class_entry *ce, zend_string *name);
+
+ZEND_API void zend_observer_function_declared_register(zend_observer_function_declared_cb cb);
+ZEND_API void ZEND_FASTCALL zend_observer_function_declared_notify(zend_op_array *op_array, zend_string *name);
+ZEND_API void zend_observer_class_linked_register(zend_observer_class_linked_cb cb);
+ZEND_API void ZEND_FASTCALL zend_observer_class_linked_notify(zend_class_entry *ce, zend_string *name);
+
 typedef void (*zend_observer_error_cb)(int type, zend_string *error_filename, uint32_t error_lineno, zend_string *message);
 
 ZEND_API void zend_observer_error_register(zend_observer_error_cb callback);
diff --git a/ext/opcache/ZendAccelerator.c b/ext/opcache/ZendAccelerator.c
@@ -1806,6 +1806,7 @@ static zend_persistent_script *opcache_compile_file(zend_file_handle *file_handl
 		CG(compiler_options) |= ZEND_COMPILE_DELAYED_BINDING;
 		CG(compiler_options) |= ZEND_COMPILE_NO_CONSTANT_SUBSTITUTION;
 		CG(compiler_options) |= ZEND_COMPILE_IGNORE_OTHER_FILES;
+		CG(compiler_options) |= ZEND_COMPILE_IGNORE_OBSERVER;
 		if (ZCG(accel_directives).file_cache) {
 			CG(compiler_options) |= ZEND_COMPILE_WITH_FILE_CACHE;
 		}
diff --git a/ext/opcache/zend_accelerator_util_funcs.c b/ext/opcache/zend_accelerator_util_funcs.c
@@ -25,6 +25,7 @@
 #include "zend_accelerator_util_funcs.h"
 #include "zend_persist.h"
 #include "zend_shared_alloc.h"
+#include "zend_observer.h"
 
 typedef int (*id_function_t)(void *, void *);
 typedef void (*unique_copy_ctor_func_t)(void *pElement);
@@ -145,6 +146,8 @@ static void zend_accel_function_hash_copy(HashTable *target, HashTable *source)
 	Bucket *p, *end;
 	zval *t;
 
+	bool call_observers = zend_observer_function_declared_observed;
+
 	zend_hash_extend(target, target->nNumUsed + source->nNumUsed, 0);
 	p = source->arData;
 	end = p + source->nNumUsed;
@@ -156,6 +159,9 @@ static void zend_accel_function_hash_copy(HashTable *target, HashTable *source)
 			goto failure;
 		}
 		_zend_hash_append_ptr_ex(target, p->key, Z_PTR(p->val), 1);
+		if (UNEXPECTED(call_observers) && *ZSTR_VAL(p->key)) { // if not rtd key
+			zend_observer_function_declared_notify(Z_PTR(p->val), p->key);
+		}
 	}
 	target->nInternalPointer = 0;
 	return;
@@ -182,6 +188,8 @@ static void zend_accel_class_hash_copy(HashTable *target, HashTable *source)
 	Bucket *p, *end;
 	zval *t;
 
+	bool call_observers = zend_observer_class_linked_observed;
+
 	zend_hash_extend(target, target->nNumUsed + source->nNumUsed, 0);
 	p = source->arData;
 	end = p + source->nNumUsed;
@@ -221,6 +229,9 @@ static void zend_accel_class_hash_copy(HashTable *target, HashTable *source)
 			 && ZSTR_HAS_CE_CACHE(ce->name)
 			 && ZSTR_VAL(p->key)[0]) {
 				ZSTR_SET_CE_CACHE_EX(ce->name, ce, 0);
+				if (UNEXPECTED(call_observers)) {
+					zend_observer_class_linked_notify(ce, p->key);
+				}
 			}
 		}
 	}
diff --git a/ext/zend_test/observer.c b/ext/zend_test/observer.c
@@ -256,6 +256,18 @@ static void fiber_suspend_observer(zend_fiber_context *from, zend_fiber_context
 	}
 }
 
+void declared_function_observer(zend_op_array *op_array, zend_string *name) {
+	if (ZT_G(observer_observe_declaring)) {
+		php_printf("%*s<!-- declared function '%s' -->\n", 2 * ZT_G(observer_nesting_depth), "", ZSTR_VAL(name));
+	}
+}
+
+void declared_class_observer(zend_class_entry *ce, zend_string *name) {
+	if (ZT_G(observer_observe_declaring)) {
+		php_printf("%*s<!-- declared class '%s' -->\n", 2 * ZT_G(observer_nesting_depth), "", ZSTR_VAL(name));
+	}
+}
+
 static ZEND_INI_MH(zend_test_observer_OnUpdateCommaList)
 {
 	zend_array **p = (zend_array **) ZEND_INI_GET_ADDR();
@@ -301,6 +313,7 @@ PHP_INI_BEGIN()
 	STD_PHP_INI_BOOLEAN("zend_test.observer.observe_all", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_observe_all, zend_zend_test_globals, zend_test_globals)
 	STD_PHP_INI_BOOLEAN("zend_test.observer.observe_includes", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_observe_includes, zend_zend_test_globals, zend_test_globals)
 	STD_PHP_INI_BOOLEAN("zend_test.observer.observe_functions", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_observe_functions, zend_zend_test_globals, zend_test_globals)
+	STD_PHP_INI_BOOLEAN("zend_test.observer.observe_declaring", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_observe_declaring, zend_zend_test_globals, zend_test_globals)
 	STD_PHP_INI_ENTRY("zend_test.observer.observe_function_names", "", PHP_INI_ALL, zend_test_observer_OnUpdateCommaList, observer_observe_function_names, zend_zend_test_globals, zend_test_globals)
 	STD_PHP_INI_BOOLEAN("zend_test.observer.show_return_type", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_show_return_type, zend_zend_test_globals, zend_test_globals)
 	STD_PHP_INI_BOOLEAN("zend_test.observer.show_return_value", "0", PHP_INI_SYSTEM, OnUpdateBool, observer_show_return_value, zend_zend_test_globals, zend_test_globals)
@@ -334,6 +347,9 @@ void zend_test_observer_init(INIT_FUNC_ARGS)
 		zend_observer_fiber_switch_register(fiber_enter_observer);
 		zend_observer_fiber_switch_register(fiber_suspend_observer);
 		zend_observer_fiber_destroy_register(fiber_destroy_observer);
+
+		zend_observer_function_declared_register(declared_function_observer);
+		zend_observer_class_linked_register(declared_class_observer);
 	}
 }
 
diff --git a/ext/zend_test/php_test.h b/ext/zend_test/php_test.h
@@ -38,6 +38,7 @@ ZEND_BEGIN_MODULE_GLOBALS(zend_test)
 	int observer_observe_all;
 	int observer_observe_includes;
 	int observer_observe_functions;
+	int observer_observe_declaring;
 	zend_array *observer_observe_function_names;
 	int observer_show_return_type;
 	int observer_show_return_value;
diff --git a/ext/zend_test/tests/observer_declarations_01.phpt b/ext/zend_test/tests/observer_declarations_01.phpt
@@ -0,0 +1,54 @@
+--TEST--
+Observer: Observe function and class declarations
+--EXTENSIONS--
+zend_test
+--INI--
+zend_test.observer.enabled=1
+zend_test.observer.observe_all=1
+zend_test.observer.observe_declaring=1
+--FILE--
+<?php
+function foo()
+{
+    echo "foo\n";
+}
+
+class A {
+}
+
+class B extends A {
+}
+
+if (time() > 0) {
+    function nested()
+    {
+    }
+
+    class C
+    {
+    }
+
+    class D extends A
+    {
+    }
+}
+
+foo();
+?>
+--EXPECTF--
+<!-- declared function 'foo' -->
+<!-- declared class 'a' -->
+<!-- declared class 'b' -->
+<!-- init '%s' -->
+<file '%s'>
+  <!-- init time() -->
+  <time>
+  </time>
+  <!-- declared function 'nested' -->
+  <!-- declared class 'c' -->
+  <!-- declared class 'd' -->
+  <!-- init foo() -->
+  <foo>
+foo
+  </foo>
+</file '%s'>

Original file line number	Diff line number	Diff line change
`@@ -31,6 +31,7 @@`
`31`	`31`	`#include "zend_inheritance.h"`
`32`	`32`	`#include "zend_ini.h"`
`33`	`33`	`#include "zend_enum.h"`
	`34`	`+#include "zend_observer.h"`
`34`	`35`
`35`	`36`	`#include <stdarg.h>`
`36`	`37`
`@@ -3263,6 +3264,7 @@ ZEND_API zend_result zend_register_class_alias_ex(const char *name, size_t name_`
`3263`	`3264`	`if (!(ce->ce_flags & ZEND_ACC_IMMUTABLE)) {`
`3264`	`3265`	`ce->refcount++;`
`3265`	`3266`	`}`
	`3267`	`+ zend_observer_class_linked_notify(ce, lcname);`
`3266`	`3268`	`return SUCCESS;`
`3267`	`3269`	`}`
`3268`	`3270`	`return FAILURE;`
Original file line number	Diff line number	Diff line change
`@@ -1093,6 +1093,7 @@ ZEND_API zend_result do_bind_function(zend_function func, zval lcname) /* {{{`
`1093`	`1093`	`if (func->common.function_name) {`
`1094`	`1094`	`zend_string_addref(func->common.function_name);`
`1095`	`1095`	`}`
	`1096`	`+ zend_observer_function_declared_notify(&func->op_array, Z_STR_P(lcname));`
`1096`	`1097`	`return SUCCESS;`
`1097`	`1098`	`}`
`1098`	`1099`	`/* }}} */`
`@@ -1116,12 +1117,14 @@ ZEND_API zend_class_entry *zend_bind_class_in_slot(`
`1116`	`1117`	`}`
`1117`	`1118`
`1118`	`1119`	`if (ce->ce_flags & ZEND_ACC_LINKED) {`
	`1120`	`+ zend_observer_class_linked_notify(ce, Z_STR_P(lcname));`
`1119`	`1121`	`return ce;`
`1120`	`1122`	`}`
`1121`	`1123`
`1122`	`1124`	`ce = zend_do_link_class(ce, lc_parent_name, Z_STR_P(lcname));`
`1123`	`1125`	`if (ce) {`
`1124`	`1126`	`ZEND_ASSERT(!EG(exception));`
	`1127`	`+ zend_observer_class_linked_notify(ce, Z_STR_P(lcname));`
`1125`	`1128`	`return ce;`
`1126`	`1129`	`}`
`1127`	`1130`
`@@ -7245,6 +7248,7 @@ static void zend_begin_func_decl(znode result, zend_op_array op_array, zend_as`
`7245`	`7248`	`if (UNEXPECTED(zend_hash_add_ptr(CG(function_table), lcname, op_array) == NULL)) {`
`7246`	`7249`	`do_bind_function_error(lcname, op_array, 1);`
`7247`	`7250`	`}`
	`7251`	`+ zend_observer_function_declared_notify(op_array, lcname);`
`7248`	`7252`	`zend_string_release_ex(lcname, 0);`
`7249`	`7253`	`return;`
`7250`	`7254`	`}`
`@@ -7877,6 +7881,7 @@ static void zend_compile_class_decl(znode result, zend_ast ast, bool toplevel)`
`7877`	`7881`	`zend_string_release(lcname);`
`7878`	`7882`	`zend_build_properties_info_table(ce);`
`7879`	`7883`	`ce->ce_flags \|= ZEND_ACC_LINKED;`
	`7884`	`+ zend_observer_class_linked_notify(ce, lcname);`
`7880`	`7885`	`return;`
`7881`	`7886`	`}`
`7882`	`7887`	`} else if (!extends_ast) {`
Original file line number	Diff line number	Diff line change
`@@ -1806,6 +1806,7 @@ static zend_persistent_script opcache_compile_file(zend_file_handle file_handl`
`1806`	`1806`	`CG(compiler_options) \|= ZEND_COMPILE_DELAYED_BINDING;`
`1807`	`1807`	`CG(compiler_options) \|= ZEND_COMPILE_NO_CONSTANT_SUBSTITUTION;`
`1808`	`1808`	`CG(compiler_options) \|= ZEND_COMPILE_IGNORE_OTHER_FILES;`
	`1809`	`+ CG(compiler_options) \|= ZEND_COMPILE_IGNORE_OBSERVER;`
`1809`	`1810`	`if (ZCG(accel_directives).file_cache) {`
`1810`	`1811`	`CG(compiler_options) \|= ZEND_COMPILE_WITH_FILE_CACHE;`
`1811`	`1812`	`}`