Fix TsHashTable related race conditions

Although TsHashTable and the according API are supposed to easily make
a HashTable thread-safe, they do not; for instance, there can be race
conditions between finding and updating entries.  We therefore avoid
the usage of TsHashTable in favor of a HashTable with our own mutex
management.

The patch has been provided by krakjoe@php.net; I only did some minor
fixes and tweaks.

diff --git a/ext/com_dotnet/com_com.c b/ext/com_dotnet/com_com.c
index fc8e84b3a144ad8fcf50cae1f1fcb59d508000f0..58a22a9c6224e6dcd8b604db829dff3fc18e2d63 100644 (file)
--- a/ext/com_dotnet/com_com.c
+++ b/ext/com_dotnet/com_com.c
@@ -267,7 +267,7 @@ PHP_FUNCTION(com_create_instance)
                        if (SUCCEEDED(ITypeLib_GetDocumentation(TL, -1, &name, NULL, NULL, NULL))) {
                                typelib_name = php_com_olestring_to_string(name, &typelib_name_len, obj->code_page);
 
-                               if (NULL != zend_ts_hash_str_add_ptr(&php_com_typelibraries, typelib_name, typelib_name_len, TL)) {
+                               if (NULL != php_com_cache_typelib(TL, typelib_name, typelib_name_len)) {
                                        php_com_import_typelib(TL, mode, obj->code_page);
 
                                        /* add a reference for the hash */

diff --git a/ext/com_dotnet/com_extension.c b/ext/com_dotnet/com_extension.c
index 94b6b65ee6ac857051ce1dcafbb92d431b873929..7ff0fd0ebd5713be37adc2b98b08d8dcc3ebc0d3 100644 (file)
--- a/ext/com_dotnet/com_extension.c
+++ b/ext/com_dotnet/com_extension.c
@@ -33,8 +33,6 @@
 ZEND_DECLARE_MODULE_GLOBALS(com_dotnet)
 static PHP_GINIT_FUNCTION(com_dotnet);
 
-TsHashTable php_com_typelibraries;
-
 zend_class_entry
        *php_com_variant_class_entry,
        *php_com_exception_class_entry,
@@ -330,8 +328,6 @@ PHP_MINIT_FUNCTION(com_dotnet)
        tmp->serialize = zend_class_serialize_deny;
        tmp->unserialize = zend_class_unserialize_deny;
 
-       zend_ts_hash_init(&php_com_typelibraries, 0, NULL, php_com_typelibrary_dtor, 1);
-
 #if HAVE_MSCOREE_H
        INIT_CLASS_ENTRY(ce, "dotnet", NULL);
        ce.create_object = php_com_object_new;
@@ -418,6 +414,9 @@ PHP_MINIT_FUNCTION(com_dotnet)
        COM_CONST(VT_UI8);
        COM_CONST(VT_I8);
 #endif
+
+       PHP_MINIT(com_typeinfo)(INIT_FUNC_ARGS_PASSTHRU);
+
        return SUCCESS;
 }
 /* }}} */
@@ -433,7 +432,8 @@ PHP_MSHUTDOWN_FUNCTION(com_dotnet)
        }
 #endif
 
-       zend_ts_hash_destroy(&php_com_typelibraries);
+       PHP_MSHUTDOWN(com_typeinfo)(INIT_FUNC_ARGS_PASSTHRU);
+
        return SUCCESS;
 }
 /* }}} */

diff --git a/ext/com_dotnet/com_typeinfo.c b/ext/com_dotnet/com_typeinfo.c
index d5afd57a89a8bf21c7367afc10ef634f4dfa72a6..44d0340af5065f3f749510f565a6088d4c494a4c 100644 (file)
--- a/ext/com_dotnet/com_typeinfo.c
+++ b/ext/com_dotnet/com_typeinfo.c
@@ -27,6 +27,33 @@
 #include "php_com_dotnet.h"
 #include "php_com_dotnet_internal.h"
 
+static HashTable php_com_typelibraries;
+
+#ifdef ZTS
+static MUTEX_T php_com_typelibraries_mutex;
+#endif
+
+PHP_MINIT_FUNCTION(com_typeinfo)
+{
+       zend_hash_init(&php_com_typelibraries, 0, NULL, php_com_typelibrary_dtor, 1);
+
+#ifdef ZTS
+       php_com_typelibraries_mutex = tsrm_mutex_alloc();
+#endif
+
+       return SUCCESS;
+}
+
+PHP_MSHUTDOWN_FUNCTION(com_typeinfo)
+{
+       zend_hash_destroy(&php_com_typelibraries);
+
+#ifdef ZTS
+       tsrm_mutex_free(php_com_typelibraries_mutex);
+#endif
+
+       return SUCCESS;
+}
 
 /* The search string can be either:
  * a) a file name
@@ -220,35 +247,58 @@ void php_com_typelibrary_dtor(zval *pDest)
        ITypeLib_Release(Lib);
 }
 
+ITypeLib *php_com_cache_typelib(ITypeLib* TL, char *cache_key, zend_long cache_key_len) {
+       ITypeLib* result;
+#ifdef ZTS
+       tsrm_mutex_lock(php_com_typelibraries_mutex);
+#endif
+
+       result = zend_hash_str_add_ptr(&php_com_typelibraries, cache_key, cache_key_len, TL);
+
+#ifdef ZTS
+       tsrm_mutex_unlock(php_com_typelibraries_mutex);
+#endif
+
+       return result;
+}
+
 PHP_COM_DOTNET_API ITypeLib *php_com_load_typelib_via_cache(char *search_string,
        int codepage, int *cached)
 {
        ITypeLib *TL;
        char *name_dup;
-       size_t l;
+       zend_string *key = zend_string_init(search_string, strlen(search_string), 1);
 
-       l = strlen(search_string);
+#ifdef ZTS
+       tsrm_mutex_lock(php_com_typelibraries_mutex);
+#endif
 
-       if ((TL = zend_ts_hash_str_find_ptr(&php_com_typelibraries, search_string, l)) != NULL) {
+       if ((TL = zend_hash_find_ptr(&php_com_typelibraries, key)) != NULL) {
                *cached = 1;
                /* add a reference for the caller */
                ITypeLib_AddRef(TL);
-               return TL;
+
+               goto php_com_load_typelib_via_cache_return;
        }
 
        *cached = 0;
-       name_dup = estrndup(search_string, l);
+       name_dup = estrndup(ZSTR_VAL(key), ZSTR_LEN(key));
        TL = php_com_load_typelib(name_dup, codepage);
        efree(name_dup);
 
        if (TL) {
-               if (NULL != zend_ts_hash_str_update_ptr(&php_com_typelibraries,
-                               search_string, l, TL)) {
+               if (NULL != zend_hash_add_ptr(&php_com_typelibraries, key, TL)) {
                        /* add a reference for the hash table */
                        ITypeLib_AddRef(TL);
                }
        }
 
+php_com_load_typelib_via_cache_return:
+#ifdef ZTS
+       tsrm_mutex_unlock(php_com_typelibraries_mutex);
+#endif
+       zend_string_release(key);
+
        return TL;
 }
 

diff --git a/ext/com_dotnet/php_com_dotnet_internal.h b/ext/com_dotnet/php_com_dotnet_internal.h
index e41b7ffdd1e7b94c9586de2a30047a6b6593625b..676d2f93300a30271f95727dc8736d50f231b2f6 100644 (file)
--- a/ext/com_dotnet/php_com_dotnet_internal.h
+++ b/ext/com_dotnet/php_com_dotnet_internal.h
@@ -27,8 +27,6 @@
 #include <dispex.h>
 #include "win32/winutil.h"
 
-#include "zend_ts_hash.h"
-
 typedef struct _php_com_dotnet_object {
        zend_object zo;
 
@@ -70,7 +68,6 @@ static inline int php_com_is_valid_object(zval *zv)
 } while(0)
 
 /* com_extension.c */
-TsHashTable php_com_typelibraries;
 zend_class_entry *php_com_variant_class_entry, *php_com_exception_class_entry, *php_com_saproxy_class_entry;
 
 /* com_handlers.c */
@@ -175,6 +172,9 @@ PHP_COM_DOTNET_API int php_com_import_typelib(ITypeLib *TL, int mode,
 void php_com_typelibrary_dtor(zval *pDest);
 ITypeInfo *php_com_locate_typeinfo(char *typelibname, php_com_dotnet_object *obj, char *dispname, int sink);
 int php_com_process_typeinfo(ITypeInfo *typeinfo, HashTable *id_to_name, int printdef, GUID *guid, int codepage);
+ITypeLib *php_com_cache_typelib(ITypeLib* TL, char *cache_key, zend_long cache_key_len);
+PHP_MINIT_FUNCTION(com_typeinfo);
+PHP_MSHUTDOWN_FUNCTION(com_typeinfo);
 
 /* com_iterator.c */
 zend_object_iterator *php_com_iter_get(zend_class_entry *ce, zval *object, int by_ref);