diff options
| -rw-r--r-- | libbutl/fdstream.cxx | 25 |
1 files changed, 22 insertions, 3 deletions
diff --git a/libbutl/fdstream.cxx b/libbutl/fdstream.cxx index 955b75d..72439ae 100644 --- a/libbutl/fdstream.cxx +++ b/libbutl/fdstream.cxx @@ -306,7 +306,14 @@ namespace butl size_t an (epptr () - pptr ()); // Amount of free space in the buffer. if (n <= an) { - memcpy (pptr (), s, n); + assert (s != nullptr || n == 0); + + // Note that the memcpy() function behavior is undefined if either of + // pointers is NULL, even if the bytes count is zero. + // + if (s != nullptr) + memcpy (pptr (), s, n); + advance (n); return n; } @@ -361,7 +368,13 @@ namespace butl an = 0; else { - memcpy (pptr (), s, an); + assert (s != nullptr || an == 0); + + // The source can not be NULL (see above for details). + // + if (s != nullptr) + memcpy (pptr (), s, an); + advance (an); } @@ -398,7 +411,13 @@ namespace butl // if (n <= static_cast<size_t> (epptr () - pbase ())) { - memcpy (pbase (), s, n); + assert (s != nullptr || n == 0); + + // The source can not be NULL (see above for details). + // + if (s != nullptr) + memcpy (pbase (), s, n); + advance (n); return sn; } |