Update to NSPR 4.10.8

nspr/pr/src/io/prfdcach.c

 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
 /* This Source Code Form is subject to the terms of the Mozilla Public
  * License, v. 2.0. If a copy of the MPL was not distributed with this
  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
 
 #include "primpl.h"
 
 #include <string.h>
 
 /*****************************************************************************/
@@ skipping 13 matching lines @@
 ** preserved before they are recycled. The environment variables are
 ** NSPR_FD_CACHE_SIZE_LOW and NSPR_FD_CACHE_SIZE_HIGH. The former sets
 ** the number of descriptors NSPR will allocate before beginning to
 ** recycle. The latter is the maximum number permitted in the cache
 ** (exclusive of those in use) at a time.
 */
 typedef struct _PR_Fd_Cache
 {
     PRLock *ml;
     PRIntn count;
-    PRStack *stack;
     PRFileDesc *head, *tail;
     PRIntn limit_low, limit_high;
 } _PR_Fd_Cache;
 
 static _PR_Fd_Cache _pr_fd_cache;
-static PRFileDesc **stack2fd = &(((PRFileDesc*)NULL)->higher);
 
 
 /*
 ** Get a FileDescriptor from the cache if one exists. If not allocate
 ** a new one from the heap.
 */
 PRFileDesc *_PR_Getfd(void)
 {
     PRFileDesc *fd;
     /*
     ** $$$
     ** This may look a little wasteful. We'll see. Right now I want to
     ** be able to toggle between caching and not at runtime to measure
     ** the differences. If it isn't too annoying, I'll leave it in.
     ** $$$$
     **
     ** The test is against _pr_fd_cache.limit_high. If that's zero,
     ** we're not doing the extended cache but going for performance.
     */
     if (0 == _pr_fd_cache.limit_high)
     {
-        PRStackElem *pop;
-        PR_ASSERT(NULL != _pr_fd_cache.stack);
-        pop = PR_StackPop(_pr_fd_cache.stack);
-        if (NULL == pop) goto allocate;
-        fd = (PRFileDesc*)((PRPtrdiff)pop - (PRPtrdiff)stack2fd);
+        goto allocate;
     }
     else
     {
         do
         {
             if (NULL == _pr_fd_cache.head) goto allocate;  /* nothing there */
             if (_pr_fd_cache.count < _pr_fd_cache.limit_low) goto allocate;
 
             /* we "should" be able to extract an fd from the cache */
             PR_Lock(_pr_fd_cache.ml);  /* need the lock to do this safely */
@@ skipping 44 matching lines @@
 ** Return a file descriptor to the cache unless there are too many in
 ** there already. If put in cache, clear the fields first.
 */
 void _PR_Putfd(PRFileDesc *fd)
 {
     PR_ASSERT(PR_NSPR_IO_LAYER == fd->identity);
     fd->methods = &_pr_faulty_methods;
     fd->identity = PR_INVALID_IO_LAYER;
     fd->secret->state = _PR_FILEDESC_FREED;
 
-    if (0 == _pr_fd_cache.limit_high)
+    if (0 != _pr_fd_cache.limit_high)
     {
-        PR_StackPush(_pr_fd_cache.stack, (PRStackElem*)(&fd->higher));
-    }
-    else
-    {
-        if (_pr_fd_cache.count > _pr_fd_cache.limit_high)
-        {
-            PR_Free(fd->secret);
-            PR_Free(fd);
-        }
-        else
+        if (_pr_fd_cache.count < _pr_fd_cache.limit_high)
         {
             PR_Lock(_pr_fd_cache.ml);
             if (NULL == _pr_fd_cache.tail)
             {
                 PR_ASSERT(0 == _pr_fd_cache.count);
                 PR_ASSERT(NULL == _pr_fd_cache.head);
                 _pr_fd_cache.head = _pr_fd_cache.tail = fd;
             }
             else
             {
                 PR_ASSERT(NULL == _pr_fd_cache.tail->higher);
                 _pr_fd_cache.tail->higher = fd;
                 _pr_fd_cache.tail = fd;  /* new value */
             }
             fd->higher = NULL;  /* always so */
             _pr_fd_cache.count += 1;  /* count the new entry */
             PR_Unlock(_pr_fd_cache.ml);
+            return;
         }
     }
+
+    PR_Free(fd->secret);
+    PR_Free(fd);
 }  /* _PR_Putfd */
 
 PR_IMPLEMENT(PRStatus) PR_SetFDCacheSize(PRIntn low, PRIntn high)
 {
     /*
     ** This can be called at any time, may adjust the cache sizes,
     ** turn the caches off, or turn them on. It is not dependent
     ** on the compilation setting of DEBUG.
     */
     if (!_pr_initialized) _PR_ImplicitInitialization();
 
     if (low > high) low = high;  /* sanity check the params */
     
     PR_Lock(_pr_fd_cache.ml);
-    if (0 == high)  /* shutting down or staying down */
-    {
-        if (0 != _pr_fd_cache.limit_high)  /* shutting down */
-        {
-            _pr_fd_cache.limit_high = 0;  /* stop use */
-            /*
-            ** Hold the lock throughout - nobody's going to want it
-            ** other than another caller to this routine. Just don't
-            ** let that happen.
-            **
-            ** Put all the cached fds onto the new cache.
-            */
-            while (NULL != _pr_fd_cache.head)
-            {
-                PRFileDesc *fd = _pr_fd_cache.head;
-                _pr_fd_cache.head = fd->higher;
-                PR_StackPush(_pr_fd_cache.stack, (PRStackElem*)(&fd->higher));
-            }
-            _pr_fd_cache.limit_low = 0;
-            _pr_fd_cache.tail = NULL;
-            _pr_fd_cache.count = 0;
-        }
-    }
-    else  /* starting up or just adjusting parameters */
-    {
-        PRBool was_using_stack = (0 == _pr_fd_cache.limit_high);
-        _pr_fd_cache.limit_low = low;
-        _pr_fd_cache.limit_high = high;
-        if (was_using_stack)  /* was using stack - feed into cache */
-        {
-            PRStackElem *pop;
-            while (NULL != (pop = PR_StackPop(_pr_fd_cache.stack)))
-            {
-                PRFileDesc *fd = (PRFileDesc*)
-                    ((PRPtrdiff)pop - (PRPtrdiff)stack2fd);
-                if (NULL == _pr_fd_cache.tail) _pr_fd_cache.tail = fd;
-                fd->higher = _pr_fd_cache.head;
-                _pr_fd_cache.head = fd;
-                _pr_fd_cache.count += 1;
-            }
-        }
-    }
+    _pr_fd_cache.limit_high = high;
+    _pr_fd_cache.limit_low = low;
     PR_Unlock(_pr_fd_cache.ml);
     return PR_SUCCESS;
 }  /* PR_SetFDCacheSize */
 
 void _PR_InitFdCache(void)
 {
     /*
     ** The fd caching is enabled by default for DEBUG builds,
     ** disabled by default for OPT builds. That default can
     ** be overridden at runtime using environment variables
@@ skipping 23 matching lines @@
         _pr_fd_cache.limit_low = FD_SETSIZE;
 
     if (_pr_fd_cache.limit_high > FD_SETSIZE)
         _pr_fd_cache.limit_high = FD_SETSIZE;
 
     if (_pr_fd_cache.limit_high < _pr_fd_cache.limit_low)
         _pr_fd_cache.limit_high = _pr_fd_cache.limit_low;
 
     _pr_fd_cache.ml = PR_NewLock();
     PR_ASSERT(NULL != _pr_fd_cache.ml);
-    _pr_fd_cache.stack = PR_CreateStack("FD");
-    PR_ASSERT(NULL != _pr_fd_cache.stack);
 
 }  /* _PR_InitFdCache */
 
 void _PR_CleanupFdCache(void)
 {
     PRFileDesc *fd, *next;
     PRStackElem *pop;
 
     for (fd = _pr_fd_cache.head; fd != NULL; fd = next)
     {
         next = fd->higher;
         PR_DELETE(fd->secret);
         PR_DELETE(fd);
     }
     _pr_fd_cache.head = NULL;
     _pr_fd_cache.tail = NULL;
     _pr_fd_cache.count = 0;
     PR_DestroyLock(_pr_fd_cache.ml);
     _pr_fd_cache.ml = NULL;
-    while ((pop = PR_StackPop(_pr_fd_cache.stack)) != NULL)
-    {
-        fd = (PRFileDesc*)((PRPtrdiff)pop - (PRPtrdiff)stack2fd);
-        PR_DELETE(fd->secret);
-        PR_DELETE(fd);
-    }
-    PR_DestroyStack(_pr_fd_cache.stack);
-    _pr_fd_cache.stack = NULL;
 }  /* _PR_CleanupFdCache */
 
 /* prfdcach.c */