1 //===-- Internal implementation header of vfscanf ---------------*- C++ -*-===//
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 #ifndef LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H
10 #define LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H
11
12 #include "src/__support/File/file.h"
13 #include "src/__support/arg_list.h"
14 #include "src/__support/macros/config.h"
15 #include "src/__support/macros/properties/architectures.h"
16 #include "src/stdio/scanf_core/reader.h"
17 #include "src/stdio/scanf_core/scanf_main.h"
18
19 #if defined(LIBC_TARGET_ARCH_IS_GPU)
20 #include "src/stdio/ferror.h"
21 #include "src/stdio/getc.h"
22 #include "src/stdio/ungetc.h"
23 #endif
24
25 #include "hdr/types/FILE.h"
26 #include <stddef.h>
27
28 namespace LIBC_NAMESPACE_DECL {
29
30 namespace internal {
31
32 #if defined(LIBC_TARGET_ARCH_IS_GPU)
33 // The GPU build provides FILE access through the host operating system's
34 // library. So here we simply use the public entrypoints like in the SYSTEM_FILE
35 // interface. Entrypoints should normally not call others, this is an exception.
36 // FIXME: We do not acquire any locks here, so this is not thread safe.
flockfile(::FILE *)37 LIBC_INLINE void flockfile(::FILE *) { return; }
38
funlockfile(::FILE *)39 LIBC_INLINE void funlockfile(::FILE *) { return; }
40
getc(void * f)41 LIBC_INLINE int getc(void *f) {
42 return LIBC_NAMESPACE::getc(reinterpret_cast<::FILE *>(f));
43 }
44
ungetc(int c,void * f)45 LIBC_INLINE void ungetc(int c, void *f) {
46 LIBC_NAMESPACE::ungetc(c, reinterpret_cast<::FILE *>(f));
47 }
48
ferror_unlocked(::FILE * f)49 LIBC_INLINE int ferror_unlocked(::FILE *f) { return LIBC_NAMESPACE::ferror(f); }
50
51 #elif !defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)
52
53 LIBC_INLINE void flockfile(FILE *f) {
54 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->lock();
55 }
56
57 LIBC_INLINE void funlockfile(FILE *f) {
58 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->unlock();
59 }
60
61 LIBC_INLINE int getc(void *f) {
62 unsigned char c;
63 auto result =
64 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->read_unlocked(&c, 1);
65 size_t r = result.value;
66 if (result.has_error() || r != 1)
67 return '\0';
68
69 return c;
70 }
71
72 LIBC_INLINE void ungetc(int c, void *f) {
73 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->ungetc_unlocked(c);
74 }
75
76 LIBC_INLINE int ferror_unlocked(FILE *f) {
77 return reinterpret_cast<LIBC_NAMESPACE::File *>(f)->error_unlocked();
78 }
79
80 #else // defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)
81
82 // Since ungetc_unlocked isn't always available, we don't acquire the lock for
83 // system files.
84 LIBC_INLINE void flockfile(::FILE *) { return; }
85
86 LIBC_INLINE void funlockfile(::FILE *) { return; }
87
88 LIBC_INLINE int getc(void *f) { return ::getc(reinterpret_cast<::FILE *>(f)); }
89
90 LIBC_INLINE void ungetc(int c, void *f) {
91 ::ungetc(c, reinterpret_cast<::FILE *>(f));
92 }
93
94 LIBC_INLINE int ferror_unlocked(::FILE *f) { return ::ferror(f); }
95
96 #endif // LIBC_COPT_STDIO_USE_SYSTEM_FILE
97
98 } // namespace internal
99
100 namespace scanf_core {
101
vfscanf_internal(::FILE * __restrict stream,const char * __restrict format,internal::ArgList & args)102 LIBC_INLINE int vfscanf_internal(::FILE *__restrict stream,
103 const char *__restrict format,
104 internal::ArgList &args) {
105 internal::flockfile(stream);
106 scanf_core::Reader reader(stream, &internal::getc, internal::ungetc);
107 int retval = scanf_core::scanf_main(&reader, format, args);
108 if (retval == 0 && internal::ferror_unlocked(stream))
109 retval = EOF;
110 internal::funlockfile(stream);
111
112 return retval;
113 }
114 } // namespace scanf_core
115 } // namespace LIBC_NAMESPACE_DECL
116
117 #endif // LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H
118