Function strlcpy

source/util.cpp:423–443

void strlcpy(LPSTR aDst, LPCSTR aSrc, size_t aDstSize) // Non-inline because it benches slightly faster that way.
// Caller must ensure that aDstSize is greater than 0.
// Caller must ensure that the entire capacity of aDst is writable, EVEN WHEN it knows that aSrc is much shorter
// than the aDstSize.  This is because the call to strncpy (which is used for its superior performance) zero-fills
// any unused portion of aDst.
// Description:
// Same as strncpy() but guarantees null-termination of aDst upon return.
// No more than aDstSize - 1 characters will be copied from aSrc into aDst
// (leaving room for the zero terminator, which is always inserted).
// This function is defined in some Unices but is not standard.  But unlike
// other versions, this one uses void for return value for reduced code size
// (since it's called in so many places).
{
	// Disabled for performance and reduced code size:
	//if (!aDst || !aSrc || !aDstSize) return aDstSize;  // aDstSize must not be zero due to the below method.
	// It might be worthwhile to have a custom char-copying-loop here someday so that number of characters
	// actually copied (not including the zero terminator) can be returned to callers who want it.
	--aDstSize; // Convert from size to length (caller has ensured that aDstSize > 0).
	strncpy(aDst, aSrc, aDstSize); // NOTE: In spite of its zero-filling, strncpy() benchmarks considerably faster than a custom loop, probably because it uses 32-bit memory operations vs. 8-bit.
	aDst[aDstSize] = '\0';
}