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