xref: /aosp_15_r20/external/llvm-libc/src/stdio/generic/puts.cpp (revision 71db0c75aadcf003ffe3238005f61d7618a3fead)
1 //===-- Implementation of puts --------------------------------------------===//
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 "src/stdio/puts.h"
10 #include "src/__support/CPP/string_view.h"
11 #include "src/__support/File/file.h"
12 
13 #include "hdr/types/FILE.h"
14 #include "src/__support/macros/config.h"
15 #include "src/errno/libc_errno.h"
16 #include <stddef.h>
17 
18 namespace LIBC_NAMESPACE_DECL {
19 
20 namespace {
21 
22 // Simple helper to unlock the file once destroyed.
23 struct ScopedLock {
ScopedLockLIBC_NAMESPACE_DECL::__anon5123db2a0111::ScopedLock24   ScopedLock(LIBC_NAMESPACE::File *stream) : stream(stream) { stream->lock(); }
~ScopedLockLIBC_NAMESPACE_DECL::__anon5123db2a0111::ScopedLock25   ~ScopedLock() { stream->unlock(); }
26 
27 private:
28   LIBC_NAMESPACE::File *stream;
29 };
30 
31 } // namespace
32 
33 LLVM_LIBC_FUNCTION(int, puts, (const char *__restrict str)) {
34   cpp::string_view str_view(str);
35 
36   // We need to lock the stream to ensure the newline is always appended.
37   ScopedLock lock(LIBC_NAMESPACE::stdout);
38 
39   auto result = LIBC_NAMESPACE::stdout->write_unlocked(str, str_view.size());
40   if (result.has_error())
41     libc_errno = result.error;
42   size_t written = result.value;
43   if (str_view.size() != written) {
44     // The stream should be in an error state in this case.
45     return EOF;
46   }
47   result = LIBC_NAMESPACE::stdout->write_unlocked("\n", 1);
48   if (result.has_error())
49     libc_errno = result.error;
50   written = result.value;
51   if (1 != written) {
52     // The stream should be in an error state in this case.
53     return EOF;
54   }
55   return 0;
56 }
57 
58 } // namespace LIBC_NAMESPACE_DECL
59