Fix distributed tracing on PHP 8

The curl extension API was upgraded from a resource to an object in php/php-src#5402.

Author: SammyK

Makefile

@@ -476,8 +476,11 @@ TEST_WEB_74 := \
 	test_opentracing_10
 
 TEST_INTEGRATIONS_80 := \
+	test_integrations_curl \
 	test_integrations_mysqli \
 	test_integrations_pdo \
+	test_integrations_guzzle5 \
+	test_integrations_guzzle6 \
 	test_integrations_predis1
 
 TEST_WEB_80 := \

bridge/php5.php renamed to bridge/curl_inject.php

@@ -60,8 +60,8 @@ function_exists('dd_trace_internal_fn') && \dd_trace_internal_fn('ddtrace_reload
 
 // Required classes and functions
 require __DIR__ . '/autoload.php';
-if (\PHP_MAJOR_VERSION === 5) {
-    require __DIR__ . '/php5.php';
+if (\PHP_MAJOR_VERSION === 8 || \PHP_MAJOR_VERSION === 5) {
+    require __DIR__ . '/curl_inject.php';
 }
 
 // Optional classes and functions

bridge/dd_init.php

@@ -162,7 +162,6 @@ if test "$PHP_DDTRACE" != "no"; then
       ext/php8/configuration_php_iface.c \
       ext/php8/ddtrace_string.c \
       ext/php8/dispatch.c \
-      ext/php8/distributed_tracing.c \
       ext/php8/dogstatsd_client.c \
       ext/php8/engine_api.c \
       ext/php8/engine_hooks.c \

config.m4

@@ -36,7 +36,6 @@
 #include "ddtrace.h"
 #include "ddtrace_string.h"
 #include "dispatch.h"
-#include "distributed_tracing.h"
 #include "dogstatsd_client.h"
 #include "engine_hooks.h"
 #include "excluded_modules.h"
@@ -420,10 +419,10 @@ static PHP_RINIT_FUNCTION(ddtrace) {
         dd_request_init_hook_rinit(TSRMLS_C);
     }
 
+    ddtrace_internal_handlers_rinit();
     ddtrace_engine_hooks_rinit(TSRMLS_C);
     ddtrace_bgs_log_rinit(PG(error_log));
     ddtrace_dispatch_init(TSRMLS_C);
-    ddtrace_distributed_tracing_rinit(TSRMLS_C);
     DDTRACE_G(disable_in_current_request) = 0;
 
     ddtrace_dogstatsd_client_rinit(TSRMLS_C);
@@ -458,7 +457,6 @@ static PHP_RSHUTDOWN_FUNCTION(ddtrace) {
     ddtrace_internal_handlers_rshutdown();
     ddtrace_dogstatsd_client_rshutdown(TSRMLS_C);
 
-    ddtrace_distributed_tracing_rshutdown(TSRMLS_C);
     ddtrace_dispatch_destroy(TSRMLS_C);
     ddtrace_free_span_id_stack(TSRMLS_C);
     ddtrace_free_span_stacks(TSRMLS_C);

ext/php8/ddtrace.c

@@ -15,14 +15,12 @@ extern zend_class_entry *ddtrace_ce_fatal_error;
 typedef struct ddtrace_span_ids_t ddtrace_span_ids_t;
 typedef struct ddtrace_span_fci ddtrace_span_fci;
 
-#if PHP_VERSION_ID >= 70000
 zval *ddtrace_spandata_property_name(zval *spandata);
 zval *ddtrace_spandata_property_resource(zval *spandata);
 zval *ddtrace_spandata_property_service(zval *spandata);
 zval *ddtrace_spandata_property_type(zval *spandata);
 zval *ddtrace_spandata_property_meta(zval *spandata);
 zval *ddtrace_spandata_property_metrics(zval *spandata);
-#endif
 
 BOOL_T ddtrace_tracer_is_limited(TSRMLS_D);
 
@@ -45,25 +43,6 @@ ZEND_BEGIN_MODULE_GLOBALS(ddtrace)
     char *dogstatsd_port;
     char *dogstatsd_buffer;
 
-    // PHP 7 uses ZEND_TLS for these
-#if PHP_VERSION_ID < 70000
-    // Distributed tracing & curl
-    HashTable *dt_http_saved_curl_headers;
-    zend_bool back_up_http_headers;
-
-    /* These ones are used for measuring the call stack depth so that we can
-     * emit a warning prior to encountering a stack overflow.
-     *
-     * A 16-bit call depth would allow us to count to 65,535, which is way more
-     * than necessary. An 8-bit depth would be inadequate (255).
-     */
-    bool should_warn_call_depth;
-    uint16_t call_depth;
-
-    // ext/curl's list entry resource type
-    int le_curl;
-#endif
-
     uint64_t trace_id;
     ddtrace_span_ids_t *span_ids_top;
     ddtrace_span_fci *open_spans_top;
@@ -92,13 +71,7 @@ ZEND_END_MODULE_GLOBALS(ddtrace)
  * defines these macros without the comma in the definition site, so that it
  * exists at the usage site.
  */
-#if PHP_VERSION_ID < 70000
-#define DDTRACE_ARG_INFO_SIZE(arg_info) ((zend_uint)(sizeof(arg_info) / sizeof(struct _zend_arg_info) - 1))
-#elif PHP_VERSION_ID < 80100
 #define DDTRACE_ARG_INFO_SIZE(arg_info) ((uint32_t)(sizeof(arg_info) / sizeof(struct _zend_internal_arg_info) - 1))
-#else
-#error Check if ZEND_FENTRY has changed in PHP 8.1 and if we need to update the macros
-#endif
 
 #define DDTRACE_FENTRY(zend_name, name, arg_info, flags) \
     { #zend_name, name, arg_info, DDTRACE_ARG_INFO_SIZE(arg_info), flags }
@@ -111,19 +84,4 @@ ZEND_END_MODULE_GLOBALS(ddtrace)
 #define DDTRACE_FALIAS(name, alias, arg_info) DDTRACE_RAW_FENTRY(#name, zif_##alias, arg_info, 0)
 #define DDTRACE_FE_END ZEND_FE_END
 
-/* Currently used on PHP 5. After a zend_execute_ex has called the previous hook
- * the execute_data cannot be trusted for some things, notably function_state.
- * So we use this struct to back up the data.
- */
-struct ddtrace_execute_data {
-    zval *This;
-    zend_class_entry *scope;
-    zend_function *fbc;
-    const zend_op *opline;
-    void **arguments;
-    zval *retval;
-    bool free_retval;
-};
-typedef struct ddtrace_execute_data ddtrace_execute_data;
-
 #endif  // DDTRACE_H

ext/php8/ddtrace.h

@@ -79,14 +79,19 @@ ZEND_RESULT_CODE ddtrace_call_method(zend_object *obj, zend_class_entry *ce, zen
 }
 
 ZEND_RESULT_CODE ddtrace_call_function(zend_function **fn_proxy, const char *name, size_t name_len, zval *retval,
-                                       int argc, zval argv[]) {
+                                       int argc, ...) {
     zend_fcall_info fci = {
         .size = sizeof(zend_fcall_info),
     };
     zend_fcall_info_cache fcc = {
         .function_handler = (fn_proxy && *fn_proxy) ? *fn_proxy : NULL,
     };
 
+    va_list argv;
+    va_start(argv, argc);
+    zend_fcall_info_argv(&fci, (uint32_t)argc, &argv);
+    va_end(argv);
+
     if (!fcc.function_handler) {
         // This avoids allocating a zend_string if fn_proxy is used
         zval fname = ddtrace_zval_stringl(name, name_len);
@@ -111,12 +116,10 @@ ZEND_RESULT_CODE ddtrace_call_function(zend_function **fn_proxy, const char *nam
     // ZVAL_COPY_VALUE(&fci.function_name, fcc.function_handler->common.function_name);
 
     fci.retval = retval;
-    fci.params = argv;
-#if PHP_VERSION_ID < 80000
-    fci.no_separation = 0;  // allow for by-ref args
-#endif
-    fci.param_count = argc;
     ZEND_RESULT_CODE result = zend_call_function(&fci, &fcc);
+    
+    zend_fcall_info_args_clear(&fci, 1);
+
     return result;
 }
 

ext/php8/distributed_tracing.c

@@ -50,7 +50,7 @@ inline zval ddtrace_zval_undef(void) {
 ZEND_RESULT_CODE ddtrace_call_method(zend_object *obj, zend_class_entry *ce, zend_function **fn_proxy,
                                      const char *fname, size_t fname_len, zval *retval, int argc, zval *argv);
 ZEND_RESULT_CODE ddtrace_call_function(zend_function **fn_proxy, const char *name, size_t name_len, zval *retval,
-                                       int argc, zval argv[]);
+                                       int argc, ...);
 
 void ddtrace_write_property(zval *obj, const char *prop, size_t prop_len, zval *value);
 bool ddtrace_property_exists(zval *object, zval *property);