Function xdr_debug_memory

src/remote/protocol.cpp:160–251

#ifdef DEBUG_XDR_MEMORY
void xdr_debug_memory(RemoteXdr* xdrs,
					  enum xdr_op xop,
					  const void* xdrvar, const void* address, ULONG length)
{
/**************************************
 *
 *	x d r _ d e b u g _ m e m o r y
 *
 **************************************
 *
 * Functional description
 *	Track memory allocation patterns of RemoteXdr aggregate
 *	types (i.e. xdr_cstring, xdr_string, etc.) to
 *	validate that memory is not leaked by overwriting
 *	RemoteXdr aggregate pointers and that freeing a packet
 *	with REMOTE_free_packet() does not miss anything.
 *
 *	All memory allocations due to marshalling RemoteXdr
 *	variables are recorded in a debug memory alloca-
 *	tion table stored at the front of a packet.
 *
 *	Once a packet is being tracked it is an assertion
 *	error if a memory allocation can not be recorded
 *	due to space limitations or if a previous memory
 *	allocation being freed cannot be found. At most
 *	P_MALLOC_SIZE entries can be stored in the memory
 *	allocation table. A rough estimate of the number
 *	of RemoteXdr aggregates that can hang off a packet can
 *	be obtained by examining the subpackets defined
 *	in <remote/protocol.h>: A guestimate of 36 at this
 *	time includes 10 strings used to decode an xdr
 *	status vector.
 *
 **************************************/
	rem_port* port = xdrs->x_public;
	fb_assert(port != 0);
	fb_assert(port->port_header.blk_type == type_port);

	// Compare the RemoteXdr variable address with the lower and upper bounds
	// of each packet to determine which packet contains it. Record or
	// delete an entry in that packet's memory allocation table.

	rem_vec* vector = port->port_packet_vector;
	if (!vector)	// Not tracking port's protocol
		return;

	ULONG i;
	for (i = 0; i < vector->vec_count; i++)
	{
		PACKET* packet = (PACKET*) vector->vec_object[i];
		if (packet)
		{
			fb_assert(packet->p_operation > op_void && packet->p_operation < op_max);

			if ((SCHAR*) xdrvar >= (SCHAR*) packet &&
				(SCHAR*) xdrvar < (SCHAR*) packet + sizeof(PACKET))
			{
				ULONG j;