libc/src/stdio/printf_core/vfprintf_internal.h

   1 //===-- Internal implementation header of vfprintf --------------*- 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_PRINTF_CORE_VFPRINTF_INTERNAL_H
  10 #define LLVM_LIBC_SRC_STDIO_PRINTF_CORE_VFPRINTF_INTERNAL_H
  11
  12 #include "src/__support/File/file.h"
  13 #include "src/__support/arg_list.h"
  14 #include "src/__support/macros/attributes.h" // For LIBC_INLINE
  15 #include "src/__support/macros/config.h"
  16 #include "src/stdio/printf_core/core_structs.h"
  17 #include "src/stdio/printf_core/printf_main.h"
  18 #include "src/stdio/printf_core/writer.h"
  19
  20 #include "hdr/types/FILE.h"
  21
  22 namespace LIBC_NAMESPACE_DECL {
  23
  24 namespace internal {
  25 #ifndef LIBC_COPT_STDIO_USE_SYSTEM_FILE
  26 LIBC_INLINE int ferror_unlocked(FILE *f) {
  27   return reinterpret_cast<LIBC_NAMESPACE::File *>(f)->error_unlocked();
  28 }
  29
  30 LIBC_INLINE void flockfile(FILE *f) {
  31   reinterpret_cast<LIBC_NAMESPACE::File *>(f)->lock();
  32 }
  33
  34 LIBC_INLINE void funlockfile(FILE *f) {
  35   reinterpret_cast<LIBC_NAMESPACE::File *>(f)->unlock();
  36 }
  37
  38 LIBC_INLINE size_t fwrite_unlocked(const void *ptr, size_t size, size_t nmemb,
  39                                    FILE *f) {
  40   return reinterpret_cast<LIBC_NAMESPACE::File *>(f)->write_unlocked(
  41       ptr, size * nmemb);
  42 }
  43 #else  // defined(LIBC_COPT_STDIO_USE_SYSTEM_FILE)
  44 LIBC_INLINE int ferror_unlocked(::FILE *f) { return ::ferror_unlocked(f); }
  45
  46 LIBC_INLINE void flockfile(::FILE *f) { ::flockfile(f); }
  47
  48 LIBC_INLINE void funlockfile(::FILE *f) { ::funlockfile(f); }
  49
  50 LIBC_INLINE size_t fwrite_unlocked(const void *ptr, size_t size, size_t nmemb,
  51                                    ::FILE *f) {
  52   return ::fwrite_unlocked(ptr, size, nmemb, f);
  53 }
  54 #endif // LIBC_COPT_STDIO_USE_SYSTEM_FILE
  55 } // namespace internal
  56
  57 namespace printf_core {
  58
  59 LIBC_INLINE int file_write_hook(cpp::string_view new_str, void *fp) {
  60   ::FILE *target_file = reinterpret_cast<::FILE *>(fp);
  61   // Write new_str to the target file. The logic preventing a zero-length write
  62   // is in the writer, so we don't check here.
  63   size_t written = internal::fwrite_unlocked(new_str.data(), sizeof(char),
  64                                              new_str.size(), target_file);
  65   if (written != new_str.size() || internal::ferror_unlocked(target_file))
  66     return FILE_WRITE_ERROR;
  67   return WRITE_OK;
  68 }
  69
  70 LIBC_INLINE int vfprintf_internal(::FILE *__restrict stream,
  71                                   const char *__restrict format,
  72                                   internal::ArgList &args) {
  73   constexpr size_t BUFF_SIZE = 1024;
  74   char buffer[BUFF_SIZE];
  75   printf_core::WriteBuffer wb(buffer, BUFF_SIZE, &file_write_hook,
  76                               reinterpret_cast<void *>(stream));
  77   Writer writer(&wb);
  78   internal::flockfile(stream);
  79   int retval = printf_main(&writer, format, args);
  80   int flushval = wb.overflow_write("");
  81   if (flushval != WRITE_OK)
  82     retval = flushval;
  83   internal::funlockfile(stream);
  84   return retval;
  85 }
  86
  87 } // namespace printf_core
  88 } // namespace LIBC_NAMESPACE_DECL
  89
  90 #endif // LLVM_LIBC_SRC_STDIO_PRINTF_CORE_VFPRINTF_INTERNAL_H