xref: /aosp_15_r20/external/llvm-libc/src/pthread/pthread_mutex_init.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Linux implementation of the pthread_mutex_init function -----------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "pthread_mutex_init.h"
10 #include "pthread_mutexattr.h"
11 
12 #include "src/__support/common.h"
13 #include "src/__support/macros/config.h"
14 #include "src/__support/threads/mutex.h"
15 
16 #include <pthread.h>
17 
18 namespace LIBC_NAMESPACE_DECL {
19 
20 static_assert(sizeof(Mutex) <= sizeof(pthread_mutex_t),
21               "The public pthread_mutex_t type cannot accommodate the internal "
22               "mutex type.");
23 
24 LLVM_LIBC_FUNCTION(int, pthread_mutex_init,
25                    (pthread_mutex_t * m,
26                     const pthread_mutexattr_t *__restrict attr)) {
27   auto mutexattr = attr == nullptr ? DEFAULT_MUTEXATTR : *attr;
28   auto err =
29       Mutex::init(reinterpret_cast<Mutex *>(m), /*is_timed=*/true,
30                   get_mutexattr_type(mutexattr) & PTHREAD_MUTEX_RECURSIVE,
31                   get_mutexattr_robust(mutexattr) & PTHREAD_MUTEX_ROBUST,
32                   get_mutexattr_pshared(mutexattr) & PTHREAD_PROCESS_SHARED);
33   return err == MutexError::NONE ? 0 : EAGAIN;
34 }
35 
36 } // namespace LIBC_NAMESPACE_DECL
37