19e9803bfSMichael Jones //===-- Implementation of strncat -----------------------------------------===//
29e9803bfSMichael Jones //
39e9803bfSMichael Jones // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
49e9803bfSMichael Jones // See https://llvm.org/LICENSE.txt for license information.
59e9803bfSMichael Jones // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
69e9803bfSMichael Jones //
79e9803bfSMichael Jones //===----------------------------------------------------------------------===//
89e9803bfSMichael Jones 
99e9803bfSMichael Jones #include "src/string/strncat.h"
109e9803bfSMichael Jones #include "src/string/string_utils.h"
119e9803bfSMichael Jones #include "src/string/strncpy.h"
129e9803bfSMichael Jones 
139e9803bfSMichael Jones #include "src/__support/common.h"
149e9803bfSMichael Jones 
159e9803bfSMichael Jones namespace __llvm_libc {
169e9803bfSMichael Jones 
179e9803bfSMichael Jones LLVM_LIBC_FUNCTION(char *, strncat,
189e9803bfSMichael Jones                    (char *__restrict dest, const char *__restrict src,
199e9803bfSMichael Jones                     size_t count)) {
20*1c92911eSMichael Jones   size_t src_length = internal::string_length(src);
21*1c92911eSMichael Jones   size_t copy_amount = src_length > count ? count : src_length;
22*1c92911eSMichael Jones   size_t dest_length = internal::string_length(dest);
23*1c92911eSMichael Jones   __llvm_libc::strncpy(dest + dest_length, src, copy_amount);
24*1c92911eSMichael Jones   dest[dest_length + copy_amount] = '\0';
259e9803bfSMichael Jones   return dest;
269e9803bfSMichael Jones }
279e9803bfSMichael Jones 
289e9803bfSMichael Jones } // namespace __llvm_libc
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