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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H10#define LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H11 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#endif24 25#include "hdr/types/FILE.h"26#include <stddef.h>27 28namespace LIBC_NAMESPACE_DECL {29 30namespace internal {31 32#if defined(LIBC_TARGET_ARCH_IS_GPU)33// The GPU build provides FILE access through the host operating system's34// library. So here we simply use the public entrypoints like in the SYSTEM_FILE35// 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.37LIBC_INLINE void flockfile(::FILE *) { return; }38 39LIBC_INLINE void funlockfile(::FILE *) { return; }40 41LIBC_INLINE int ferror_unlocked(::FILE *f) { return LIBC_NAMESPACE::ferror(f); }42 43LIBC_INLINE int getc(::FILE *f) { return LIBC_NAMESPACE::getc(f); }44 45LIBC_INLINE void ungetc(int c, ::FILE *f) { LIBC_NAMESPACE::ungetc(c, f); }46 47#elif !defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)48 49LIBC_INLINE void flockfile(FILE *f) {50 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->lock();51}52 53LIBC_INLINE void funlockfile(FILE *f) {54 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->unlock();55}56 57LIBC_INLINE int ferror_unlocked(FILE *f) {58 return reinterpret_cast<LIBC_NAMESPACE::File *>(f)->error_unlocked();59}60 61LIBC_INLINE int getc(FILE *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 72LIBC_INLINE void ungetc(int c, FILE *f) {73 reinterpret_cast<LIBC_NAMESPACE::File *>(f)->ungetc_unlocked(c);74}75 76#else // defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)77 78// Since ungetc_unlocked isn't always available, we don't acquire the lock for79// system files.80LIBC_INLINE void flockfile(::FILE *) { return; }81 82LIBC_INLINE void funlockfile(::FILE *) { return; }83 84LIBC_INLINE int ferror_unlocked(::FILE *f) { return ::ferror(f); }85 86LIBC_INLINE int getc(::FILE *f) { return ::getc(f); }87 88LIBC_INLINE void ungetc(int c, ::FILE *f) { ::ungetc(c, f); }89 90#endif // LIBC_COPT_STDIO_USE_SYSTEM_FILE91 92} // namespace internal93 94namespace scanf_core {95 96class StreamReader : public Reader<StreamReader> {97 ::FILE *stream;98 99public:100 LIBC_INLINE StreamReader(::FILE *stream) : stream(stream) {}101 102 LIBC_INLINE char getc() {103 return static_cast<char>(internal::getc(static_cast<FILE *>(stream)));104 }105 LIBC_INLINE void ungetc(int c) {106 internal::ungetc(c, static_cast<FILE *>(stream));107 }108};109 110LIBC_INLINE int vfscanf_internal(::FILE *__restrict stream,111 const char *__restrict format,112 internal::ArgList &args) {113 internal::flockfile(stream);114 scanf_core::StreamReader reader(stream);115 int retval = scanf_core::scanf_main(&reader, format, args);116 if (retval == 0 && internal::ferror_unlocked(stream))117 retval = EOF;118 internal::funlockfile(stream);119 120 return retval;121}122} // namespace scanf_core123} // namespace LIBC_NAMESPACE_DECL124 125#endif // LLVM_LIBC_SRC_STDIO_SCANF_CORE_VFSCANF_INTERNAL_H126