Split SafeUDPpacket and SafeUDPpacketV.

SafeUDPpacketV is much more complex due to the UDP packet splitting machinery.

include/SafeUDPpacketV.h

@@ -0,0 +1,60 @@
+#pragma once
+
+#include "SafeUDPpacket.h"
+
+class SafeUDPpacketV
+{
+	std::vector<SafeUDPpacket> m_packetV;
+	public:
+		SafeUDPpacketV (const void*, const int, const int mtu = 1450);
+		SafeUDPpacketV (int howmany, int size)
+		{
+			UDPpacket** p;
+			m_packetV.reserve (howmany);
+			if (NULL == (p = SDLNet_AllocPacketV (howmany, size)))
+			{
+				throw "SDLNet_AllocPacketV: " + std::string (SDLNet_GetError ());
+			}
+			else
+			{
+				for (; (p != NULL) && (*p != NULL); p++)
+				{
+					m_packetV.push_back (SafeUDPpacket (*p));
+				}
+				SDL_assert ((m_packetV.size () > 0) && (howmany == (int)m_packetV.size ()));
+				/*
+				 * SDLNet_FreePacketV just calls SDLNet_FreePacket on each packet.
+				 * The "packetV" itself is just something allocated on the heap.
+				 * We don't need this any longer.
+				 */
+				SDL_free (p);
+			}
+		}
+		int Send (UDPsocket sock)
+		{
+			size_t size;
+			int numsent;
+			UDPpacket** pV;
+			size = m_packetV.size ();
+			if (NULL != (pV = (UDPpacket**)SDL_malloc (sizeof (UDPpacket*) * size)))
+			{
+				for (size_t i = 0; i < size; i++)
+					pV[i] = m_packetV[i].get ();
+				numsent = SDLNet_UDP_SendV (sock, pV, size);
+				SDL_free (pV);
+			}
+			return numsent;
+		}
+
+		size_t size (void) const              { return m_packetV.size (); }
+		const SafeUDPpacket& get (size_t idx) { return m_packetV.at (idx); }
+
+		void channel (int channel)       { for (auto& p : m_packetV) { p.channel (channel); } }
+		void len (int len)               { for (auto& p : m_packetV) { p.len (len); } }
+		void maxlen (int maxlen)         { for (auto& p : m_packetV) { p.maxlen (maxlen); } }
+		void status (int status)         { for (auto& p : m_packetV) { p.status (status); } }
+		void address (IPaddress address) { for (auto& p : m_packetV) { p.address (address); } }
+
+		std::string toString (void);
+};
+

src/SafeUDPpacketV.cpp

@@ -0,0 +1,80 @@
+#include "SafeUDPpacketV.h"
+
+SafeUDPpacketV::SafeUDPpacketV (const void* buf, const int size, const int mtu)
+{
+	int howmany, i, len, numsent;
+	const uint8_t* bufPtr;
+	const uint8_t* bufPtrEnd;
+
+	SDL_assert (NULL != buf);
+
+	SDL_assert (mtu > 0);
+	howmany = (int) ceil ((double) size / (double) mtu);
+
+	i = 0;
+	numsent = 0;
+	bufPtr = (const uint8_t*) buf;
+	bufPtrEnd = bufPtr + size;
+	while ((i < howmany) && (bufPtr < bufPtrEnd) && (numsent < size))
+	{
+		SafeUDPpacket p (mtu);
+
+		len = size - numsent;
+		if (len > mtu)
+			len = mtu;
+		/* Use SDLNet_UDP_Send to send an empty packet instead... it's probably simpler than all this machinery. */
+		if (len < 1)
+			break;
+
+		/* Clear the entire data ... TODO */
+		p.len (mtu);
+		p.clear ();
+
+		/* Set the actual length */
+		p.len (len);
+		p.maxlen (size);
+
+		/* only memcpy in the relevant bits */
+		p.slurp (bufPtr, len);
+
+		m_packetV.push_back (std::move (p));
+
+		/* Advance */
+		bufPtr += len;
+		numsent += len;
+		i++;
+	}
+
+	SDL_assert (howmany == (int)m_packetV.size ());
+}
+
+
+std::string
+SafeUDPpacketV::toString (void)
+{
+	int howmany, maxlen, mtu, numrecv;
+	char* bufPtr;
+	char* bufPtrEnd;
+	std::string buf;
+
+	howmany = m_packetV.size ();
+	SDL_assert (howmany > 0);
+
+	maxlen = m_packetV[0].maxlen ();
+	SDL_assert (maxlen > 0);
+	buf.reserve (maxlen);
+	bufPtr = &buf[0];
+	bufPtrEnd = bufPtr + maxlen;
+
+	for (numrecv = 0; (numrecv < howmany) && (bufPtr < bufPtrEnd); numrecv++)
+	{
+		mtu = m_packetV[numrecv].len ();
+		SDL_assert (mtu > 0);
+		memcpy (bufPtr, m_packetV[numrecv].data (), mtu);
+		bufPtr += mtu;
+	}
+
+	SDL_assert (numrecv == howmany);
+
+	return buf;
+}