Interned strings unification for TS/NTS

Hereby, interned strings are supported in thread safe PHP. The patch
implements two types of interned strings

- interning per process, strings are not freed till process end
- interning per request, strings are freed at request end

There is no runtime interning.

With Opcache, all the permanent iterned strings are copied into SHM on
startup, additional copying into SHM might happen on demand.

2 files changed, 29 insertions, 4 deletions

diff --git a/TSRM/TSRM.c b/TSRM/TSRM.c
index 6669df6d43..2c7a40a2de 100644
--- a/TSRM/TSRM.c
+++ b/TSRM/TSRM.c
@@ -55,8 +55,9 @@ static int					resource_types_table_size;
 static MUTEX_T tsmm_mutex;	/* thread-safe memory manager mutex */
 
 /* New thread handlers */
-static tsrm_thread_begin_func_t tsrm_new_thread_begin_handler;
-static tsrm_thread_end_func_t tsrm_new_thread_end_handler;
+static tsrm_thread_begin_func_t tsrm_new_thread_begin_handler = NULL;
+static tsrm_thread_end_func_t tsrm_new_thread_end_handler = NULL;
+static tsrm_shutdown_func_t tsrm_shutdown_handler = NULL;
 
 /* Debug support */
 int tsrm_error(int level, const char *format, ...);
@@ -120,6 +121,8 @@ static int32 tls_key;
 # warning tsrm_set_interpreter_context is probably broken on this platform
 #endif
 
+TSRM_TLS uint8_t in_main_thread = 0;
+
 /* Startup TSRM (call once for the entire process) */
 TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debug_level, char *debug_filename)
 {
@@ -136,6 +139,9 @@ TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debu
 	tls_key = tls_allocate();
 #endif
 
+	/* ensure singleton */
+	in_main_thread = 1;
+
 	tsrm_error_file = stderr;
 	tsrm_error_set(debug_level, debug_filename);
 	tsrm_tls_table_size = expected_threads;
@@ -158,8 +164,6 @@ TSRM_API int tsrm_startup(int expected_threads, int expected_resources, int debu
 
 	tsmm_mutex = tsrm_mutex_alloc();
 
-	tsrm_new_thread_begin_handler = tsrm_new_thread_end_handler = NULL;
-
 	TSRM_ERROR((TSRM_ERROR_LEVEL_CORE, "Started up TSRM, %d expected threads, %d expected resources", expected_threads, expected_resources));
 	return 1;
 }
@@ -170,6 +174,11 @@ TSRM_API void tsrm_shutdown(void)
 {
 	int i;
 
+	if (!in_main_thread) {
+		/* ensure singleton */
+		return;
+	}
+
 	if (tsrm_tls_table) {
 		for (i=0; i<tsrm_tls_table_size; i++) {
 			tsrm_tls_entry *p = tsrm_tls_table[i], *next_p;
@@ -212,6 +221,12 @@ TSRM_API void tsrm_shutdown(void)
 #elif defined(TSRM_WIN32)
 	TlsFree(tls_key);
 #endif
+	if (tsrm_shutdown_handler) {
+		tsrm_shutdown_handler();
+	}
+	tsrm_new_thread_begin_handler = NULL;
+	tsrm_new_thread_end_handler = NULL;
+	tsrm_shutdown_handler = NULL;
 }
 
 
@@ -740,6 +755,14 @@ TSRM_API void *tsrm_set_new_thread_end_handler(tsrm_thread_end_func_t new_thread
 }
 
 
+TSRM_API void *tsrm_set_shutdown_handler(tsrm_shutdown_func_t shutdown_handler)
+{
+	void *retval = (void *) tsrm_shutdown_handler;
+
+	tsrm_shutdown_handler = shutdown_handler;
+	return retval;
+}
+
 
 /*
  * Debug support
diff --git a/TSRM/TSRM.h b/TSRM/TSRM.h
index f9bb241050..2ffcbfee76 100644
--- a/TSRM/TSRM.h
+++ b/TSRM/TSRM.h
@@ -128,6 +128,7 @@ TSRM_API void ts_free_id(ts_rsrc_id id);
 
 typedef void (*tsrm_thread_begin_func_t)(THREAD_T thread_id);
 typedef void (*tsrm_thread_end_func_t)(THREAD_T thread_id);
+typedef void (*tsrm_shutdown_func_t)(void);
 
 
 TSRM_API int tsrm_error(int level, const char *format, ...);
@@ -145,6 +146,7 @@ TSRM_API int tsrm_sigmask(int how, const sigset_t *set, sigset_t *oldset);
 
 TSRM_API void *tsrm_set_new_thread_begin_handler(tsrm_thread_begin_func_t new_thread_begin_handler);
 TSRM_API void *tsrm_set_new_thread_end_handler(tsrm_thread_end_func_t new_thread_end_handler);
+TSRM_API void *tsrm_set_shutdown_handler(tsrm_shutdown_func_t shutdown_handler);
 
 /* these 3 APIs should only be used by people that fully understand the threading model
  * used by PHP/Zend and the selected SAPI. */