[libc-commits] [PATCH] D111583: [libc] Add strncat and fix strcat

[Tue Ly via Phabricator via libc-commits]

lntue added inline comments.


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Comment at: libc/src/string/strncat.cpp:23
+  size_t destLength = internal::string_length(dest);
+  __llvm_libc::strncpy(dest + destLength, src, count);
+  dest[destLength + copyAmount] = '\0';
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I think you should use `copyAmount` here instead of `count`, since for strncpy it is specifically said that when srcLength < count, extra '\0' 's will be appended upto `count`.  On the other hand, strncat is only specified to be null-terminated.


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Comment at: libc/test/src/string/strncat_test.cpp:60
+
+  result = __llvm_libc::strncat(dest, abc, 3);
+  ASSERT_EQ(dest, result);
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Nit: Also add tests where count = srcLength + 1 and count > srcLength + 1.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D111583/new/

https://reviews.llvm.org/D111583