libc/src/stdlib/strfromd.cpp

   1 //===-- Implementation of strfromd ------------------------------*- 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 #include "src/stdlib/strfromd.h"
  10 #include "src/__support/macros/config.h"
  11 #include "src/stdlib/str_from_util.h"
  12
  13 namespace LIBC_NAMESPACE_DECL {
  14
  15 LLVM_LIBC_FUNCTION(int, strfromd,
  16                    (char *__restrict s, size_t n, const char *__restrict format,
  17                     double fp)) {
  18   LIBC_ASSERT(s != nullptr);
  19
  20   printf_core::FormatSection section =
  21       internal::parse_format_string(format, fp);
  22   printf_core::WriteBuffer wb(s, (n > 0 ? n - 1 : 0));
  23   printf_core::Writer writer(&wb);
  24
  25   int result = 0;
  26   if (section.has_conv)
  27     result = internal::strfromfloat_convert<double>(&writer, section);
  28   else
  29     result = writer.write(section.raw_string);
  30
  31   if (result < 0)
  32     return result;
  33
  34   if (n > 0)
  35     wb.buff[wb.buff_cur] = '\0';
  36
  37   return writer.get_chars_written();
  38 }
  39
  40 } // namespace LIBC_NAMESPACE_DECL