buffer.c

Go to the documentation of this file.

/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */
 
#include <string.h>
 
#include "MEM_guardedalloc.h"
 
#include "BLI_buffer.h"
#include "BLI_utildefines.h"
 
#include "BLI_strict_flags.h"
 
static void *buffer_alloc(BLI_Buffer *buffer, const size_t len)
{
  return MEM_mallocN(buffer->elem_size * len, "BLI_Buffer.data");
}
 
static void *buffer_realloc(BLI_Buffer *buffer, const size_t len)
{
  return MEM_reallocN_id(buffer->data, buffer->elem_size * len, "BLI_Buffer.data");
}
 
void BLI_buffer_resize(BLI_Buffer *buffer, const size_t new_count)
{
  if (UNLIKELY(new_count > buffer->alloc_count)) {
    if (buffer->flag & BLI_BUFFER_USE_STATIC) {
      void *orig = buffer->data;
 
      buffer->data = buffer_alloc(buffer, new_count);
      memcpy(buffer->data, orig, buffer->elem_size * buffer->count);
      buffer->alloc_count = new_count;
      buffer->flag &= ~BLI_BUFFER_USE_STATIC;
    }
    else {
      if (buffer->alloc_count && (new_count < buffer->alloc_count * 2)) {
        buffer->alloc_count *= 2;
      }
      else {
        buffer->alloc_count = new_count;
      }
 
      buffer->data = buffer_realloc(buffer, buffer->alloc_count);
    }
  }
 
  buffer->count = new_count;
}
 
void BLI_buffer_reinit(BLI_Buffer *buffer, const size_t new_count)
{
  if (UNLIKELY(new_count > buffer->alloc_count)) {
    if ((buffer->flag & BLI_BUFFER_USE_STATIC) == 0) {
      if (buffer->data) {
        MEM_freeN(buffer->data);
      }
    }
 
    if (buffer->alloc_count && (new_count < buffer->alloc_count * 2)) {
      buffer->alloc_count *= 2;
    }
    else {
      buffer->alloc_count = new_count;
    }
 
    buffer->flag &= ~BLI_BUFFER_USE_STATIC;
    buffer->data = buffer_alloc(buffer, buffer->alloc_count);
  }
 
  buffer->count = new_count;
}
 
/* Callers use BLI_buffer_append_array. */
void _bli_buffer_append_array(BLI_Buffer *buffer, void *new_data, size_t count)
{
  size_t size = buffer->count;
  BLI_buffer_resize(buffer, size + count);
 
  uint8_t *bytes = (uint8_t *)buffer->data;
  memcpy(bytes + size * buffer->elem_size, new_data, count * buffer->elem_size);
}
 
/* callers use BLI_buffer_free */
void _bli_buffer_free(BLI_Buffer *buffer)
{
  if ((buffer->flag & BLI_BUFFER_USE_STATIC) == 0) {
    if (buffer->data) {
      MEM_freeN(buffer->data);
    }
  }
  memset(buffer, 0, sizeof(*buffer));
}