unify handler overwrite into function

Author: ZNeumann

agent/php_observer.c

@@ -126,6 +126,36 @@ static zend_observer_fcall_handlers nr_php_fcall_register_handlers(
                      nr_php_observer_fcall_end;
   return handlers;
 }
+
+bool nr_php_observer_is_registered(zend_function* func) {
+  zend_observer_fcall_begin_handler *begin_handler;
+  if (func == NULL) {
+    return false;
+  }
+  begin_handler = (zend_observer_fcall_begin_handler *)&ZEND_OP_ARRAY_EXTENSION((&(func)->common), zend_observer_fcall_op_array_extension);
+  // begin_handler will be NULL if the observer hasn't been installed yet.
+  // *begin_Handler will be NULL if the function has not yet been called.
+  return (begin_handler && *begin_handler);
+}
+
+void nr_php_observer_overwrite_handlers(zend_function* func, nruserfn_t* wraprec) {
+  if (nr_php_observer_is_registered(func)) {
+    if (zend_observer_remove_begin_handler(func, NRINI(tt_detail) ?
+                                                  nr_php_observer_fcall_begin :
+                                                  nr_php_observer_empty_fcall_begin)) {
+      zend_observer_add_begin_handler(func, wraprec->special_instrumentation_before ?
+                                                 (zend_observer_fcall_begin_handler)wraprec->special_instrumentation_before :
+                                                 nr_php_observer_fcall_begin);
+    }
+    if (zend_observer_remove_end_handler(func, NRINI(tt_detail) ?
+                                                nr_php_observer_fcall_end :
+                                                nr_php_observer_empty_fcall_end)) {
+      zend_observer_add_end_handler(func, wraprec->special_instrumentation ?
+                                               (zend_observer_fcall_end_handler)wraprec->special_instrumentation :
+                                               nr_php_observer_fcall_end);
+    }
+  }
+}
 #endif
 
 

agent/php_observer.h

@@ -17,6 +17,7 @@
 #if ZEND_MODULE_API_NO >= ZEND_8_0_X_API_NO /* PHP8+ */
 
 #include "Zend/zend_observer.h"
+#include "php_user_instrument.h"
 
 /*
  * Purpose: There are a few various places, aside from the php_execute_* family
@@ -77,6 +78,9 @@ void nr_php_observer_fcall_end(zend_execute_data* execute_data,
 
 
 #if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
+bool nr_php_observer_is_registered(zend_function* func);
+void nr_php_observer_overwrite_handlers(zend_function* func, nruserfn_t* wraprec);
+
 void nr_php_observer_empty_fcall_begin(zend_execute_data* execute_data);
 void nr_php_observer_fcall_begin_instrumented(zend_execute_data* execute_data);
 

agent/php_user_instrument.c

@@ -452,7 +452,6 @@ nruserfn_t* nr_php_add_custom_tracer_named(const char* namestr,
   nruserfn_t* p;
 #if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
   zend_function* orig_func;
-  zend_observer_fcall_begin_handler *begin_handler;
 #endif
 
   wraprec = nr_php_user_wraprec_create_named(namestr, namestrlen);
@@ -494,28 +493,7 @@ nruserfn_t* nr_php_add_custom_tracer_named(const char* namestr,
    * module shutdown */
   nr_php_add_custom_tracer_common(wraprec);
 #if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-  if (orig_func) {
-    // Before messing with our handlers, we must ensure that the observer fields of the function are initialized
-    begin_handler = (zend_observer_fcall_begin_handler *)&ZEND_OP_ARRAY_EXTENSION((&(orig_func)->common), zend_observer_fcall_op_array_extension);
-    // begin_handler will be NULL if the observer hasn't been installed yet.
-    // *begin_Handler will be NULL if the function has not yet been called.
-    if (begin_handler && *begin_handler) {
-      if (zend_observer_remove_begin_handler(orig_func, NRINI(tt_detail) ?
-                                                  nr_php_observer_fcall_begin :
-                                                  nr_php_observer_empty_fcall_begin)) {
-        zend_observer_add_begin_handler(orig_func, wraprec->special_instrumentation_before ?
-                                                 (zend_observer_fcall_begin_handler)wraprec->special_instrumentation_before :
-                                                 nr_php_observer_fcall_begin_instrumented);
-      }
-      if (zend_observer_remove_end_handler(orig_func, NRINI(tt_detail) ?
-                                                nr_php_observer_fcall_end :
-                                                nr_php_observer_empty_fcall_end)) {
-        zend_observer_add_end_handler(orig_func, wraprec->special_instrumentation ?
-                                               (zend_observer_fcall_end_handler)wraprec->special_instrumentation :
-                                               nr_php_observer_fcall_end);
-      }
-    }
-  }
+  nr_php_observer_overwrite_handlers(orig_func, wraprec);
 #endif
 
   return wraprec; /* return the new wraprec */

agent/php_wrapper.c

@@ -83,10 +83,7 @@ nruserfn_t* nr_php_wrap_callable_before_after(
     zend_function* callable,
     nrspecialfn_t before_callback,
     nrspecialfn_t after_callback) {
-  char* name = NULL;
-#if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-  zend_observer_fcall_begin_handler *begin_handler;
-#endif
+    char* name = NULL;
 
   /* creates a transient wraprec */
   nruserfn_t* wraprec = nr_php_add_custom_tracer_callable(callable TSRMLS_CC);
@@ -104,33 +101,7 @@ nruserfn_t* nr_php_wrap_callable_before_after(
     nr_free(name);
   }
 #if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-      if (callable) {
-        // Before messing with our handlers, we must ensure that the observer fields of the function are initialized
-        begin_handler = (zend_observer_fcall_begin_handler *)&ZEND_OP_ARRAY_EXTENSION((&(callable)->common), zend_observer_fcall_op_array_extension);
-        // begin_handler will be NULL if the observer hasn't been installed yet.
-        // *begin_Handler will be NULL if the function has not yet been called.
-        if (begin_handler && *begin_handler) {
-    name = nr_php_function_debug_name(callable);
-          php_printf("AHHHHHHH %s\n", name);
-    nr_free(name);
-          // It is okay to attempt to remove a handler that doesn't exist
-          // TODO this could remove nr_php_observer_fcall_begin/end and then re-add it :)
-          if (zend_observer_remove_begin_handler(callable, NRINI(tt_detail) ?
-                                                        nr_php_observer_fcall_begin :
-                                                        nr_php_observer_empty_fcall_begin)) {
-            zend_observer_add_begin_handler(callable, wraprec->special_instrumentation_before ?
-                                                       (zend_observer_fcall_begin_handler)wraprec->special_instrumentation_before :
-                                                       nr_php_observer_fcall_begin);
-          }
-          if (zend_observer_remove_end_handler(callable, NRINI(tt_detail) ?
-                                                      nr_php_observer_fcall_end :
-                                                      nr_php_observer_empty_fcall_end)) {
-            zend_observer_add_end_handler(callable, wraprec->special_instrumentation ?
-                                                     (zend_observer_fcall_end_handler)wraprec->special_instrumentation :
-                                                     nr_php_observer_fcall_end);
-          }
-        }
-      }
+  nr_php_observer_overwrite_handlers(callable, wraprec);
 #endif
 
   return wraprec;
@@ -172,9 +143,6 @@ nruserfn_t* nr_php_wrap_callable(zend_function* callable,
                                  nrspecialfn_t callback TSRMLS_DC) {
   /* creates a transient wraprec */
   nruserfn_t* wraprec = nr_php_add_custom_tracer_callable(callable TSRMLS_CC);
-#if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-  zend_observer_fcall_begin_handler *begin_handler;
-#endif
 
   if (wraprec && callback) {
     if ((NULL != wraprec->special_instrumentation)
@@ -186,30 +154,7 @@ nruserfn_t* nr_php_wrap_callable(zend_function* callable,
     } else {
       wraprec->special_instrumentation = callback;
 #if ZEND_MODULE_API_NO >= ZEND_8_2_X_API_NO
-      if (callable) {
-        // Before messing with our handlers, we must ensure that the observer fields of the function are initialized
-        begin_handler = (zend_observer_fcall_begin_handler *)&ZEND_OP_ARRAY_EXTENSION((&(callable)->common), zend_observer_fcall_op_array_extension);
-        // begin_handler will be NULL if the observer hasn't been installed yet.
-        // *begin_Handler will be NULL if the function has not yet been called.
-        if (begin_handler && *begin_handler) {
-          // It is okay to attempt to remove a handler that doesn't exist
-          // TODO this could remove nr_php_observer_fcall_begin/end and then re-add it :)
-          if (zend_observer_remove_begin_handler(callable, NRINI(tt_detail) ?
-                                                        nr_php_observer_fcall_begin :
-                                                        nr_php_observer_empty_fcall_begin)) {
-            zend_observer_add_begin_handler(callable, wraprec->special_instrumentation_before ?
-                                                       (zend_observer_fcall_begin_handler)wraprec->special_instrumentation_before :
-                                                       nr_php_observer_fcall_begin);
-          }
-          if (zend_observer_remove_end_handler(callable, NRINI(tt_detail) ?
-                                                      nr_php_observer_fcall_end :
-                                                      nr_php_observer_empty_fcall_end)) {
-            zend_observer_add_end_handler(callable, wraprec->special_instrumentation ?
-                                                     (zend_observer_fcall_end_handler)wraprec->special_instrumentation :
-                                                     nr_php_observer_fcall_end);
-          }
-        }
-      }
+      nr_php_observer_overwrite_handlers(callable, wraprec);
 #endif
     }
   }