llvm-project

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//===-- Implementation of strncpy -----------------------------------------===//
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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/string/strncpy.h"
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#include "src/__support/common.h"
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#include <stddef.h> // For size_t.
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namespace LIBC_NAMESPACE {
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LLVM_LIBC_FUNCTION(char *, strncpy,
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                   (char *__restrict dest, const char *__restrict src,
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                    size_t n)) {
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  size_t i = 0;
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  // Copy up until \0 is found.
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  for (; i < n && src[i] != '\0'; ++i)
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    dest[i] = src[i];
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  // When n>strlen(src), n-strlen(src) \0 are appended.
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  for (; i < n; ++i)
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    dest[i] = '\0';
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  return dest;
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}
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} // namespace LIBC_NAMESPACE
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