leo hendrickson / Mbed OS S

simple-mbed-cloud-client/mbed-cloud-client/update-client-hub/modules/atomic-queue/source/critical-posix.c@0:25fa8795676b, 2021-04-18 (annotated)

Committer:
leothedragon
Date:
Sun Apr 18 15:20:23 2021 +0000
Revision:
0:25fa8795676b
DS

Who changed what in which revision?

UserRevisionLine numberNew contents of line
leothedragon 0:25fa8795676b 1 // ----------------------------------------------------------------------------
leothedragon 0:25fa8795676b 2 // Copyright 2015-2017 ARM Ltd.
leothedragon 0:25fa8795676b 3 //
leothedragon 0:25fa8795676b 4 // SPDX-License-Identifier: Apache-2.0
leothedragon 0:25fa8795676b 5 //
leothedragon 0:25fa8795676b 6 // Licensed under the Apache License, Version 2.0 (the "License");
leothedragon 0:25fa8795676b 7 // you may not use this file except in compliance with the License.
leothedragon 0:25fa8795676b 8 // You may obtain a copy of the License at
leothedragon 0:25fa8795676b 9 //
leothedragon 0:25fa8795676b 10 // http://www.apache.org/licenses/LICENSE-2.0
leothedragon 0:25fa8795676b 11 //
leothedragon 0:25fa8795676b 12 // Unless required by applicable law or agreed to in writing, software
leothedragon 0:25fa8795676b 13 // distributed under the License is distributed on an "AS IS" BASIS,
leothedragon 0:25fa8795676b 14 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
leothedragon 0:25fa8795676b 15 // See the License for the specific language governing permissions and
leothedragon 0:25fa8795676b 16 // limitations under the License.
leothedragon 0:25fa8795676b 17 // ----------------------------------------------------------------------------
leothedragon 0:25fa8795676b 18
leothedragon 0:25fa8795676b 19 #if defined(TARGET_LIKE_POSIX) && !defined(ATOMIC_QUEUE_USE_PAL)
leothedragon 0:25fa8795676b 20
leothedragon 0:25fa8795676b 21 // It's probably a better idea to define _POSIX_SOURCE in the target description
leothedragon 0:25fa8795676b 22 #ifndef _XOPEN_SOURCE
leothedragon 0:25fa8795676b 23 #define _XOPEN_SOURCE 600
leothedragon 0:25fa8795676b 24 #endif
leothedragon 0:25fa8795676b 25
leothedragon 0:25fa8795676b 26 #include <stdint.h>
leothedragon 0:25fa8795676b 27 #include <assert.h>
leothedragon 0:25fa8795676b 28 #include <unistd.h>
leothedragon 0:25fa8795676b 29 #include <signal.h>
leothedragon 0:25fa8795676b 30 #include <pthread.h>
leothedragon 0:25fa8795676b 31
leothedragon 0:25fa8795676b 32 // Module include
leothedragon 0:25fa8795676b 33 #include "aq_critical.h"
leothedragon 0:25fa8795676b 34
leothedragon 0:25fa8795676b 35 static pthread_mutex_t *get_mutex()
leothedragon 0:25fa8795676b 36 {
leothedragon 0:25fa8795676b 37 static int initialized = 0;
leothedragon 0:25fa8795676b 38 static pthread_mutex_t Mutex;
leothedragon 0:25fa8795676b 39 if (!initialized) {
leothedragon 0:25fa8795676b 40 pthread_mutexattr_t Attr;
leothedragon 0:25fa8795676b 41 pthread_mutexattr_init(&Attr);
leothedragon 0:25fa8795676b 42 pthread_mutexattr_settype(&Attr, PTHREAD_MUTEX_RECURSIVE);
leothedragon 0:25fa8795676b 43 pthread_mutex_init(&Mutex, &Attr);
leothedragon 0:25fa8795676b 44 initialized = 1;
leothedragon 0:25fa8795676b 45 }
leothedragon 0:25fa8795676b 46 return &Mutex;
leothedragon 0:25fa8795676b 47 }
leothedragon 0:25fa8795676b 48
leothedragon 0:25fa8795676b 49 static volatile unsigned irq_nesting_depth = 0;
leothedragon 0:25fa8795676b 50 static sigset_t old_sig_set;
leothedragon 0:25fa8795676b 51
leothedragon 0:25fa8795676b 52 void aq_critical_section_enter()
leothedragon 0:25fa8795676b 53 {
leothedragon 0:25fa8795676b 54 pthread_mutex_lock(get_mutex());
leothedragon 0:25fa8795676b 55 if (++irq_nesting_depth == 1) {
leothedragon 0:25fa8795676b 56 int rc;
leothedragon 0:25fa8795676b 57 sigset_t full_set;
leothedragon 0:25fa8795676b 58 rc = sigfillset(&full_set);
leothedragon 0:25fa8795676b 59 assert(rc == 0);
leothedragon 0:25fa8795676b 60 rc = sigprocmask(SIG_BLOCK, &full_set, &old_sig_set);
leothedragon 0:25fa8795676b 61 assert(rc == 0);
leothedragon 0:25fa8795676b 62 }
leothedragon 0:25fa8795676b 63 }
leothedragon 0:25fa8795676b 64
leothedragon 0:25fa8795676b 65 void aq_critical_section_exit(void)
leothedragon 0:25fa8795676b 66 {
leothedragon 0:25fa8795676b 67 assert(irq_nesting_depth > 0);
leothedragon 0:25fa8795676b 68 if (--irq_nesting_depth == 0) {
leothedragon 0:25fa8795676b 69 int rc = sigprocmask(SIG_SETMASK, &old_sig_set, NULL);
leothedragon 0:25fa8795676b 70 assert(rc == 0);
leothedragon 0:25fa8795676b 71 }
leothedragon 0:25fa8795676b 72 pthread_mutex_unlock(get_mutex());
leothedragon 0:25fa8795676b 73 }
leothedragon 0:25fa8795676b 74 #endif // defined(TARGET_LIKE_POSIX)