common/mbedtls/threading.h

   1 /**
   2  * \file threading.h
   3  *
   4  * \brief Threading abstraction layer
   5  */
   6 /*
   7  *  Copyright The Mbed TLS Contributors
   8  *  SPDX-License-Identifier: Apache-2.0
   9  *
  10  *  Licensed under the Apache License, Version 2.0 (the "License"); you may
  11  *  not use this file except in compliance with the License.
  12  *  You may obtain a copy of the License at
  13  *
  14  *  http://www.apache.org/licenses/LICENSE-2.0
  15  *
  16  *  Unless required by applicable law or agreed to in writing, software
  17  *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
  18  *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  19  *  See the License for the specific language governing permissions and
  20  *  limitations under the License.
  21  */
  22 #ifndef MBEDTLS_THREADING_H
  23 #define MBEDTLS_THREADING_H
  24
  25 #if !defined(MBEDTLS_CONFIG_FILE)
  26 #include "mbedtls/config.h"
  27 #else
  28 #include MBEDTLS_CONFIG_FILE
  29 #endif
  30
  31 #include <stdlib.h>
  32
  33 #ifdef __cplusplus
  34 extern "C" {
  35 #endif
  36
  37 /* MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE is deprecated and should not be
  38  * used. */
  39 #define MBEDTLS_ERR_THREADING_FEATURE_UNAVAILABLE         -0x001A  /**< The selected feature is not available. */
  40
  41 #define MBEDTLS_ERR_THREADING_BAD_INPUT_DATA              -0x001C  /**< Bad input parameters to function. */
  42 #define MBEDTLS_ERR_THREADING_MUTEX_ERROR                 -0x001E  /**< Locking / unlocking / free failed with error code. */
  43
  44 #if defined(MBEDTLS_THREADING_PTHREAD)
  45 #include <pthread.h>
  46 typedef struct mbedtls_threading_mutex_t {
  47     pthread_mutex_t mutex;
  48     /* is_valid is 0 after a failed init or a free, and nonzero after a
  49      * successful init. This field is not considered part of the public
  50      * API of Mbed TLS and may change without notice. */
  51     char is_valid;
  52 } mbedtls_threading_mutex_t;
  53 #endif
  54
  55 #if defined(MBEDTLS_THREADING_ALT)
  56 /* You should define the mbedtls_threading_mutex_t type in your header */
  57 #include "threading_alt.h"
  58
  59 /**
  60  * \brief           Set your alternate threading implementation function
  61  *                  pointers and initialize global mutexes. If used, this
  62  *                  function must be called once in the main thread before any
  63  *                  other mbed TLS function is called, and
  64  *                  mbedtls_threading_free_alt() must be called once in the main
  65  *                  thread after all other mbed TLS functions.
  66  *
  67  * \note            mutex_init() and mutex_free() don't return a status code.
  68  *                  If mutex_init() fails, it should leave its argument (the
  69  *                  mutex) in a state such that mutex_lock() will fail when
  70  *                  called with this argument.
  71  *
  72  * \param mutex_init    the init function implementation
  73  * \param mutex_free    the free function implementation
  74  * \param mutex_lock    the lock function implementation
  75  * \param mutex_unlock  the unlock function implementation
  76  */
  77 void mbedtls_threading_set_alt(void (*mutex_init)(mbedtls_threading_mutex_t *),
  78                                void (*mutex_free)(mbedtls_threading_mutex_t *),
  79                                int (*mutex_lock)(mbedtls_threading_mutex_t *),
  80                                int (*mutex_unlock)(mbedtls_threading_mutex_t *));
  81
  82 /**
  83  * \brief               Free global mutexes.
  84  */
  85 void mbedtls_threading_free_alt(void);
  86 #endif /* MBEDTLS_THREADING_ALT */
  87
  88 #if defined(MBEDTLS_THREADING_C)
  89 /*
  90  * The function pointers for mutex_init, mutex_free, mutex_ and mutex_unlock
  91  *
  92  * All these functions are expected to work or the result will be undefined.
  93  */
  94 extern void (*mbedtls_mutex_init)(mbedtls_threading_mutex_t *mutex);
  95 extern void (*mbedtls_mutex_free)(mbedtls_threading_mutex_t *mutex);
  96 extern int (*mbedtls_mutex_lock)(mbedtls_threading_mutex_t *mutex);
  97 extern int (*mbedtls_mutex_unlock)(mbedtls_threading_mutex_t *mutex);
  98
  99 /*
 100  * Global mutexes
 101  */
 102 #if defined(MBEDTLS_FS_IO)
 103 extern mbedtls_threading_mutex_t mbedtls_threading_readdir_mutex;
 104 #endif
 105
 106 #if defined(MBEDTLS_HAVE_TIME_DATE) && !defined(MBEDTLS_PLATFORM_GMTIME_R_ALT)
 107 /* This mutex may or may not be used in the default definition of
 108  * mbedtls_platform_gmtime_r(), but in order to determine that,
 109  * we need to check POSIX features, hence modify _POSIX_C_SOURCE.
 110  * With the current approach, this declaration is orphaned, lacking
 111  * an accompanying definition, in case mbedtls_platform_gmtime_r()
 112  * doesn't need it, but that's not a problem. */
 113 extern mbedtls_threading_mutex_t mbedtls_threading_gmtime_mutex;
 114 #endif /* MBEDTLS_HAVE_TIME_DATE && !MBEDTLS_PLATFORM_GMTIME_R_ALT */
 115
 116 #endif /* MBEDTLS_THREADING_C */
 117
 118 #ifdef __cplusplus
 119 }
 120 #endif
 121
 122 #endif /* threading.h */