free ring buffer

1 files changed, 4 insertions, 3 deletions

diff --git a/libical/src/libical/icalmemory.c b/libical/src/libical/icalmemory.c
index 058ef37..18d7ef9 100644
--- a/libical/src/libical/icalmemory.c
+++ b/libical/src/libical/icalmemory.c
@@ -1,313 +1,314 @@
 /* -*- Mode: C -*-
   ======================================================================
   FILE: icalmemory.c
   CREATOR: eric 30 June 1999
   
   $Id$
   $Locker$
     
  The contents of this file are subject to the Mozilla Public License
  Version 1.0 (the "License"); you may not use this file except in
  compliance with the License. You may obtain a copy of the License at
  http://www.mozilla.org/MPL/
  
  Software distributed under the License is distributed on an "AS IS"
  basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
  the License for the specific language governing rights and
  limitations under the License.
  
 
  This program is free software; you can redistribute it and/or modify
  it under the terms of either: 
 
     The LGPL as published by the Free Software Foundation, version
     2.1, available at: http://www.fsf.org/copyleft/lesser.html
 
   Or:
 
     The Mozilla Public License Version 1.0. You may obtain a copy of
     the License at http://www.mozilla.org/MPL/
 
  The Original Code is icalmemory.h
 
  ======================================================================*/
 
 /**
  * @file icalmemory.c
  * @brief Common memory management routines.
  *
  * libical often passes strings back to the caller. To make these
  * interfaces simple, I did not want the caller to have to pass in a
  * memory buffer, but having libical pass out newly allocated memory
  * makes it difficult to de-allocate the memory.
  * 
  * The ring buffer in this scheme makes it possible for libical to pass
  * out references to memory which the caller does not own, and be able
  * to de-allocate the memory later. The ring allows libical to have
  * several buffers active simultaneously, which is handy when creating
  * string representations of components. 
  */
 
 #define ICALMEMORY_C
 
 #ifdef HAVE_CONFIG_H
 #include "config.h"
 #endif
 
 #ifdef DMALLOC
 #include "dmalloc.h"
 #endif
 
 #include "icalmemory.h"
 #include "icalerror.h"
 
 #include <stdio.h> /* for printf (debugging) */
 #include <stdlib.h> /* for malloc, realloc */
 #include <string.h> /* for memset(), strdup */
 
 #ifdef WIN32
 #include <windows.h>
 #endif
 
-#define BUFFER_RING_SIZE 2500
-#define MIN_BUFFER_SIZE 200
+#define BUFFER_RING_SIZE 50
+#define MIN_BUFFER_SIZE 64
 
 
 /* HACK. Not threadsafe */
 
 typedef struct {
         int pos;
         void *ring[BUFFER_RING_SIZE];
 } buffer_ring;
 
 void icalmemory_free_tmp_buffer (void* buf);
 void icalmemory_free_ring_byval(buffer_ring *br);
 
 static buffer_ring* global_buffer_ring = 0;
 
 #ifdef HAVE_PTHREAD
 #include <pthread.h>
 
 static pthread_key_t  ring_key;
 static pthread_once_t ring_key_once = PTHREAD_ONCE_INIT;
 
 static void ring_destroy(void * buf) {
     if (buf) icalmemory_free_ring_byval((buffer_ring *) buf);
     pthread_setspecific(ring_key, NULL);
 }
 
 static void ring_key_alloc(void) {  
     pthread_key_create(&ring_key, ring_destroy);
 }
 #endif
 
 
 static buffer_ring * buffer_ring_new(void) {
         buffer_ring *br;
         int i;
 
         br = (buffer_ring *)malloc(sizeof(buffer_ring));
 
         for(i=0; i<BUFFER_RING_SIZE; i++){
             br->ring[i]  = 0;
         }
         br->pos = 0;
         return(br);
 }
 
 
 #ifdef HAVE_PTHREAD
 static buffer_ring* get_buffer_ring_pthread(void) {
     buffer_ring *br;
 
     pthread_once(&ring_key_once, ring_key_alloc);
 
     br = pthread_getspecific(ring_key);
 
     if (!br) {
         br = buffer_ring_new();
         pthread_setspecific(ring_key, br);
     }
     return(br);
 }
 #endif
 
 /* get buffer ring via a single global for a non-threaded program */
 static buffer_ring* get_buffer_ring_global(void) {
     if (global_buffer_ring == 0) {
         global_buffer_ring = buffer_ring_new();
     }
     return(global_buffer_ring);
 }
 
 static buffer_ring *get_buffer_ring(void) {
 #ifdef HAVE_PTHREAD
         return(get_buffer_ring_pthread());
 #else
         return get_buffer_ring_global();
 #endif
 }
 
 
 /** Add an existing buffer to the buffer ring */
 void  icalmemory_add_tmp_buffer(void* buf)
 {
     buffer_ring *br = get_buffer_ring();
 
 
     /* Wrap around the ring */
     if(++(br->pos) == BUFFER_RING_SIZE){
         br->pos = 0;
     }
 
     /* Free buffers as their slots are overwritten */
     if ( br->ring[br->pos] != 0){
         free( br->ring[br->pos]);
     }
 
     /* Assign the buffer to a slot */
     br->ring[br->pos] = buf; 
 }
 
 
 /**
  * Create a new temporary buffer on the ring. Libical owns these and
  * will deallocate them. 
  */
 
 void*
 icalmemory_tmp_buffer (size_t size)
 {
     char *buf;
 
     if (size < MIN_BUFFER_SIZE){
         size = MIN_BUFFER_SIZE;
     }
     
     buf = (void*)malloc(size);
 
     if( buf == 0){
         icalerror_set_errno(ICAL_NEWFAILED_ERROR);
         return 0;
     }
 
     memset(buf,0,size); 
 
     icalmemory_add_tmp_buffer(buf);
 
     return buf;
 }
 
 /** get rid of this buffer ring */
 void icalmemory_free_ring_byval(buffer_ring *br) {
    int i;
    for(i=0; i<BUFFER_RING_SIZE; i++){
     if ( br->ring[i] != 0){
        free( br->ring[i]);
     }
     }
    free(br);
 }
 
 void icalmemory_free_ring()
 {
    buffer_ring *br;
    br = get_buffer_ring();
-
    icalmemory_free_ring_byval(br);
+   if ( global_buffer_ring == br )
+       global_buffer_ring = 0; 
 }
 
 
 
 /** Like strdup, but the buffer is on the ring. */
 char*
 icalmemory_tmp_copy(const char* str)
 {
     char* b = icalmemory_tmp_buffer(strlen(str)+1);
 
     strcpy(b,str);
 
     return b;
 }
     
 
 char* icalmemory_strdup(const char *s)
 {
     return strdup(s);
 }
 
 void
 icalmemory_free_tmp_buffer (void* buf)
 {
    if(buf == 0)
    {
        return;
    }
 
    free(buf);
 }
 
 
 /*
  * These buffer routines create memory the old fashioned way -- so the
  * caller will have to deallocate the new memory 
  */
 
 void* icalmemory_new_buffer(size_t size)
 {
     void *b = malloc(size);
 
     if( b == 0){
         icalerror_set_errno(ICAL_NEWFAILED_ERROR);
         return 0;
     }
 
     memset(b,0,size); 
 
     return b;
 }
 
 void* icalmemory_resize_buffer(void* buf, size_t size)
 {
     void *b = realloc(buf, size);
 
     if( b == 0){
         icalerror_set_errno(ICAL_NEWFAILED_ERROR);
         return 0;
     }
 
    return b;
 }
 
 void icalmemory_free_buffer(void* buf)
 {
     free(buf);
 }
 
 void 
 icalmemory_append_string(char** buf, char** pos, size_t* buf_size, 
                               const char* string)
 {
     char *new_buf;
     char *new_pos;
 
     size_t data_length, final_length, string_length;
 
 #ifndef ICAL_NO_INTERNAL_DEBUG
     icalerror_check_arg_rv( (buf!=0),"buf");
     icalerror_check_arg_rv( (*buf!=0),"*buf");
     icalerror_check_arg_rv( (pos!=0),"pos");
     icalerror_check_arg_rv( (*pos!=0),"*pos");
     icalerror_check_arg_rv( (buf_size!=0),"buf_size");
     icalerror_check_arg_rv( (*buf_size!=0),"*buf_size");
     icalerror_check_arg_rv( (string!=0),"string");
 #endif 
 
     string_length = strlen(string);
     data_length = (size_t)*pos - (size_t)*buf;    
     final_length = data_length + string_length; 
 
     if ( final_length >= (size_t) *buf_size) {
 
         
         *buf_size  = (*buf_size) * 2  + final_length;