xref: /llvm-project/libc/src/string/strncat.cpp (revision 5ff3ff33ff930e4ec49da7910612d8a41eb068cb)
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"
10*5ff3ff33SPetr Hosek #include "src/__support/macros/config.h"
119e9803bfSMichael Jones #include "src/string/string_utils.h"
129e9803bfSMichael Jones #include "src/string/strncpy.h"
139e9803bfSMichael Jones 
149e9803bfSMichael Jones #include "src/__support/common.h"
159e9803bfSMichael Jones 
16*5ff3ff33SPetr Hosek namespace LIBC_NAMESPACE_DECL {
179e9803bfSMichael Jones 
189e9803bfSMichael Jones LLVM_LIBC_FUNCTION(char *, strncat,
199e9803bfSMichael Jones                    (char *__restrict dest, const char *__restrict src,
209e9803bfSMichael Jones                     size_t count)) {
211c92911eSMichael Jones   size_t src_length = internal::string_length(src);
221c92911eSMichael Jones   size_t copy_amount = src_length > count ? count : src_length;
231c92911eSMichael Jones   size_t dest_length = internal::string_length(dest);
24b6bc9d72SGuillaume Chatelet   LIBC_NAMESPACE::strncpy(dest + dest_length, src, copy_amount);
251c92911eSMichael Jones   dest[dest_length + copy_amount] = '\0';
269e9803bfSMichael Jones   return dest;
279e9803bfSMichael Jones }
289e9803bfSMichael Jones 
29*5ff3ff33SPetr Hosek } // namespace LIBC_NAMESPACE_DECL
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