text: /**
   * \file memory_buffer_alloc.h
   *
   * \brief Buffer-based memory allocator
   */
  /*
   *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
   *  SPDX-License-Identifier: Apache-2.0
   *
   *  Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
   *
   *  Unless required by applicable law or agreed to in writing, software
   *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
   *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   *  See the License for the specific language governing permissions and
   *  limitations under the License.
   *
   *  This file is part of mbed TLS (https://tls.mbed.org)
   */
  #ifndef MBEDTLS_MEMORY_BUFFER_ALLOC_H
  #define MBEDTLS_MEMORY_BUFFER_ALLOC_H
  
  #if !defined(MBEDTLS_CONFIG_FILE)
  #include "config.h"
  #else
  #include MBEDTLS_CONFIG_FILE
  #endif
  
  #include <stddef.h>
  
  /**
   * \name SECTION: Module settings
   *
   * The configuration options you can set for this module are in this section.
   * Either change them in config.h or define them on the compiler command line.
   * \{
   */
  
  #if !defined(MBEDTLS_MEMORY_ALIGN_MULTIPLE)
  #define MBEDTLS_MEMORY_ALIGN_MULTIPLE       4 /**< Align on multiples of this value */
  #endif
  
  /* \} name SECTION: Module settings */
  
  #define MBEDTLS_MEMORY_VERIFY_NONE         0
  #define MBEDTLS_MEMORY_VERIFY_ALLOC        (1 << 0)
  #define MBEDTLS_MEMORY_VERIFY_FREE         (1 << 1)
  #define MBEDTLS_MEMORY_VERIFY_ALWAYS       (MBEDTLS_MEMORY_VERIFY_ALLOC | MBEDTLS_MEMORY_VERIFY_FREE)
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * \brief   Initialize use of stack-based memory allocator.
   *          The stack-based allocator does memory management inside the
   *          presented buffer and does not call calloc() and free().
   *          It sets the global mbedtls_calloc() and mbedtls_free() pointers
   *          to its own functions.
   *          (Provided mbedtls_calloc() and mbedtls_free() are thread-safe if
   *           MBEDTLS_THREADING_C is defined)
   *
   * \note    This code is not optimized and provides a straight-forward
   *          implementation of a stack-based memory allocator.
   *
   * \param buf   buffer to use as heap
   * \param len   size of the buffer
   */
  void mbedtls_memory_buffer_alloc_init( unsigned char *buf, size_t len );
  
  /**
   * \brief   Free the mutex for thread-safety and clear remaining memory
   */
  void mbedtls_memory_buffer_alloc_free( void );
  
  /**
   * \brief   Determine when the allocator should automatically verify the state
   *          of the entire chain of headers / meta-data.
   *          (Default: MBEDTLS_MEMORY_VERIFY_NONE)
   *
   * \param verify    One of MBEDTLS_MEMORY_VERIFY_NONE, MBEDTLS_MEMORY_VERIFY_ALLOC,
   *                  MBEDTLS_MEMORY_VERIFY_FREE or MBEDTLS_MEMORY_VERIFY_ALWAYS
   */
  void mbedtls_memory_buffer_set_verify( int verify );
  
  #if defined(MBEDTLS_MEMORY_DEBUG)
  /**
   * \brief   Print out the status of the allocated memory (primarily for use
   *          after a program should have de-allocated all memory)
   *          Prints out a list of 'still allocated' blocks and their stack
   *          trace if MBEDTLS_MEMORY_BACKTRACE is defined.
   */
  void mbedtls_memory_buffer_alloc_status( void );
  
  /**
   * \brief   Get the peak heap usage so far
   *
   * \param max_used      Peak number of bytes in use or committed. This
   *                      includes bytes in allocated blocks too small to split
   *                      into smaller blocks but larger than the requested size.
   * \param max_blocks    Peak number of blocks in use, including free and used
   */
  void mbedtls_memory_buffer_alloc_max_get( size_t *max_used, size_t *max_blocks );
  
  /**
   * \brief   Reset peak statistics
   */
  void mbedtls_memory_buffer_alloc_max_reset( void );
  
  /**
   * \brief   Get the current heap usage
   *
   * \param cur_used      Current number of bytes in use or committed. This
   *                      includes bytes in allocated blocks too small to split
   *                      into smaller blocks but larger than the requested size.
   * \param cur_blocks    Current number of blocks in use, including free and used
   */
  void mbedtls_memory_buffer_alloc_cur_get( size_t *cur_used, size_t *cur_blocks );
  #endif /* MBEDTLS_MEMORY_DEBUG */
  
  /**
   * \brief   Verifies that all headers in the memory buffer are correct
   *          and contain sane values. Helps debug buffer-overflow errors.
   *
   *          Prints out first failure if MBEDTLS_MEMORY_DEBUG is defined.
   *          Prints out full header information if MBEDTLS_MEMORY_DEBUG
   *          is defined. (Includes stack trace information for each block if
   *          MBEDTLS_MEMORY_BACKTRACE is defined as well).
   *
   * \return             0 if verified, 1 otherwise
   */
  int mbedtls_memory_buffer_alloc_verify( void );
  
  #if defined(MBEDTLS_SELF_TEST)
  /**
   * \brief          Checkup routine
   *
   * \return         0 if successful, or 1 if a test failed
   */
  int mbedtls_memory_buffer_alloc_self_test( int verbose );
  #endif
  
  #ifdef __cplusplus
  }
  #endif
  
  #endif /* memory_buffer_alloc.h */
  