mirror of
				https://github.com/ossrs/srs.git
				synced 2025-03-09 15:49:59 +00:00 
			
		
		
		
	
		
			
				
	
	
		
			109 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			109 lines
		
	
	
	
		
			3.1 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
 | |
|  * Copyright 2001-2017 The OpenSSL Project Authors. All Rights Reserved.
 | |
|  *
 | |
|  * Licensed under the OpenSSL license (the "License").  You may not use
 | |
|  * this file except in compliance with the License.  You can obtain a copy
 | |
|  * in the file LICENSE in the source distribution or at
 | |
|  * https://www.openssl.org/source/license.html
 | |
|  */
 | |
| 
 | |
| #include "e_os.h"
 | |
| #include "eng_local.h"
 | |
| 
 | |
| /*
 | |
|  * Initialise a engine type for use (or up its functional reference count if
 | |
|  * it's already in use). This version is only used internally.
 | |
|  */
 | |
| int engine_unlocked_init(ENGINE *e)
 | |
| {
 | |
|     int to_return = 1;
 | |
| 
 | |
|     if ((e->funct_ref == 0) && e->init)
 | |
|         /*
 | |
|          * This is the first functional reference and the engine requires
 | |
|          * initialisation so we do it now.
 | |
|          */
 | |
|         to_return = e->init(e);
 | |
|     if (to_return) {
 | |
|         /*
 | |
|          * OK, we return a functional reference which is also a structural
 | |
|          * reference.
 | |
|          */
 | |
|         e->struct_ref++;
 | |
|         e->funct_ref++;
 | |
|         engine_ref_debug(e, 0, 1);
 | |
|         engine_ref_debug(e, 1, 1);
 | |
|     }
 | |
|     return to_return;
 | |
| }
 | |
| 
 | |
| /*
 | |
|  * Free a functional reference to a engine type. This version is only used
 | |
|  * internally.
 | |
|  */
 | |
| int engine_unlocked_finish(ENGINE *e, int unlock_for_handlers)
 | |
| {
 | |
|     int to_return = 1;
 | |
| 
 | |
|     /*
 | |
|      * Reduce the functional reference count here so if it's the terminating
 | |
|      * case, we can release the lock safely and call the finish() handler
 | |
|      * without risk of a race. We get a race if we leave the count until
 | |
|      * after and something else is calling "finish" at the same time -
 | |
|      * there's a chance that both threads will together take the count from 2
 | |
|      * to 0 without either calling finish().
 | |
|      */
 | |
|     e->funct_ref--;
 | |
|     engine_ref_debug(e, 1, -1);
 | |
|     if ((e->funct_ref == 0) && e->finish) {
 | |
|         if (unlock_for_handlers)
 | |
|             CRYPTO_THREAD_unlock(global_engine_lock);
 | |
|         to_return = e->finish(e);
 | |
|         if (unlock_for_handlers)
 | |
|             CRYPTO_THREAD_write_lock(global_engine_lock);
 | |
|         if (!to_return)
 | |
|             return 0;
 | |
|     }
 | |
|     REF_ASSERT_ISNT(e->funct_ref < 0);
 | |
|     /* Release the structural reference too */
 | |
|     if (!engine_free_util(e, 0)) {
 | |
|         ENGINEerr(ENGINE_F_ENGINE_UNLOCKED_FINISH, ENGINE_R_FINISH_FAILED);
 | |
|         return 0;
 | |
|     }
 | |
|     return to_return;
 | |
| }
 | |
| 
 | |
| /* The API (locked) version of "init" */
 | |
| int ENGINE_init(ENGINE *e)
 | |
| {
 | |
|     int ret;
 | |
|     if (e == NULL) {
 | |
|         ENGINEerr(ENGINE_F_ENGINE_INIT, ERR_R_PASSED_NULL_PARAMETER);
 | |
|         return 0;
 | |
|     }
 | |
|     if (!RUN_ONCE(&engine_lock_init, do_engine_lock_init)) {
 | |
|         ENGINEerr(ENGINE_F_ENGINE_INIT, ERR_R_MALLOC_FAILURE);
 | |
|         return 0;
 | |
|     }
 | |
|     CRYPTO_THREAD_write_lock(global_engine_lock);
 | |
|     ret = engine_unlocked_init(e);
 | |
|     CRYPTO_THREAD_unlock(global_engine_lock);
 | |
|     return ret;
 | |
| }
 | |
| 
 | |
| /* The API (locked) version of "finish" */
 | |
| int ENGINE_finish(ENGINE *e)
 | |
| {
 | |
|     int to_return = 1;
 | |
| 
 | |
|     if (e == NULL)
 | |
|         return 1;
 | |
|     CRYPTO_THREAD_write_lock(global_engine_lock);
 | |
|     to_return = engine_unlocked_finish(e, 1);
 | |
|     CRYPTO_THREAD_unlock(global_engine_lock);
 | |
|     if (!to_return) {
 | |
|         ENGINEerr(ENGINE_F_ENGINE_FINISH, ENGINE_R_FINISH_FAILED);
 | |
|         return 0;
 | |
|     }
 | |
|     return to_return;
 | |
| }
 |