llvm-project

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//===-- Implementation of strfroml ------------------------------*- C++ -*-===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#include "src/stdlib/strfroml.h"
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#include "src/stdlib/str_from_util.h"
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namespace LIBC_NAMESPACE {
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LLVM_LIBC_FUNCTION(int, strfroml,
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                   (char *__restrict s, size_t n, const char *__restrict format,
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                    long double fp)) {
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  LIBC_ASSERT(s != nullptr);
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  printf_core::FormatSection section =
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      internal::parse_format_string(format, fp);
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  // To ensure that the conversion function actually uses long double,
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  // the length modifier has to be set to LenghtModifier::L
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  section.length_modifier = printf_core::LengthModifier::L;
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  printf_core::WriteBuffer wb(s, (n > 0 ? n - 1 : 0));
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  printf_core::Writer writer(&wb);
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  int result = 0;
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  if (section.has_conv)
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    result = internal::strfromfloat_convert<long double>(&writer, section);
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  else
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    result = writer.write(section.raw_string);
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  if (result < 0)
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    return result;
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  if (n > 0)
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    wb.buff[wb.buff_cur] = '\0';
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  return writer.get_chars_written();
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}
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} // namespace LIBC_NAMESPACE
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