From ec633f3bd80b7566c96bd6bc656814d0bcaae000 Mon Sep 17 00:00:00 2001 From: rubidium Date: Tue, 2 Jan 2007 17:34:03 +0000 Subject: (svn r7751) -Codechange: move network_* to a new network map. Furthermore move the low level network functions to network/core, so they can be reused by the masterserver and website-serverlist-updater. --- network/core/packet.c | 216 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 216 insertions(+) create mode 100644 network/core/packet.c (limited to 'network/core/packet.c') diff --git a/network/core/packet.c b/network/core/packet.c new file mode 100644 index 000000000..957bd2ad6 --- /dev/null +++ b/network/core/packet.c @@ -0,0 +1,216 @@ +/* $Id$ */ + +#ifdef ENABLE_NETWORK + +#include "../../stdafx.h" +#include "../../macros.h" +#include "../../string.h" + +#include "os_abstraction.h" +#include "config.h" +#include "packet.h" + +/** + * @file packet.h Basic functions to create, fill and read packets. + */ + + +/* Do not want to include functions.h and all required headers */ +extern void NORETURN CDECL error(const char *str, ...); + + +/** + * Create a packet for sending + * @param type the of packet + * @return the newly created packet + */ +Packet *NetworkSend_Init(PacketType type) +{ + Packet *packet = malloc(sizeof(Packet)); + /* An error is inplace here, because it simply means we ran out of memory. */ + if (packet == NULL) error("Failed to allocate Packet"); + + /* Skip the size so we can write that in before sending the packet */ + packet->size = sizeof(packet->size); + packet->buffer[packet->size++] = type; + packet->pos = 0; + + return packet; +} + +/** + * Writes the packet size from the raw packet from packet->size + * @param packet the packet to write the size of + */ +void NetworkSend_FillPacketSize(Packet *packet) +{ + packet->buffer[0] = GB(packet->size, 0, 8); + packet->buffer[1] = GB(packet->size, 8, 8); +} + +/** + * The next couple of functions make sure we can send + * uint8, uint16, uint32 and uint64 endian-safe + * over the network. The least significant bytes are + * sent first. + * + * So 0x01234567 would be sent as 67 45 23 01. + */ + +void NetworkSend_uint8(Packet *packet, uint8 data) +{ + assert(packet->size < sizeof(packet->buffer) - sizeof(data)); + packet->buffer[packet->size++] = data; +} + +void NetworkSend_uint16(Packet *packet, uint16 data) +{ + assert(packet->size < sizeof(packet->buffer) - sizeof(data)); + packet->buffer[packet->size++] = GB(data, 0, 8); + packet->buffer[packet->size++] = GB(data, 8, 8); +} + +void NetworkSend_uint32(Packet *packet, uint32 data) +{ + assert(packet->size < sizeof(packet->buffer) - sizeof(data)); + packet->buffer[packet->size++] = GB(data, 0, 8); + packet->buffer[packet->size++] = GB(data, 8, 8); + packet->buffer[packet->size++] = GB(data, 16, 8); + packet->buffer[packet->size++] = GB(data, 24, 8); +} + +void NetworkSend_uint64(Packet *packet, uint64 data) +{ + assert(packet->size < sizeof(packet->buffer) - sizeof(data)); + packet->buffer[packet->size++] = GB(data, 0, 8); + packet->buffer[packet->size++] = GB(data, 8, 8); + packet->buffer[packet->size++] = GB(data, 16, 8); + packet->buffer[packet->size++] = GB(data, 24, 8); + packet->buffer[packet->size++] = GB(data, 32, 8); + packet->buffer[packet->size++] = GB(data, 40, 8); + packet->buffer[packet->size++] = GB(data, 48, 8); + packet->buffer[packet->size++] = GB(data, 56, 8); +} + +/** + * Sends a string over the network. It sends out + * the string + '\0'. No size-byte or something. + */ +void NetworkSend_string(Packet *packet, const char* data) +{ + assert(data != NULL); + assert(packet->size < sizeof(packet->buffer) - strlen(data) - 1); + while ((packet->buffer[packet->size++] = *data++) != '\0') {} +} + + +/** + * Receiving commands + * Again, the next couple of functions are endian-safe + * see the comment before NetworkSend_uint8 for more info. + */ + + +extern uint CloseConnection(NetworkClientState *cs); + +/** Is it safe to read from the packet, i.e. didn't we run over the buffer ? */ +static inline bool CanReadFromPacket(NetworkClientState *cs, Packet *packet, uint bytes_to_read) +{ + /* Don't allow reading from a closed socket */ + if (HasClientQuit(cs)) return false; + + /* Check if variable is within packet-size */ + if (packet->pos + bytes_to_read > packet->size) { + CloseConnection(cs); + return false; + } + + return true; +} + +/** + * Reads the packet size from the raw packet and stores it in the packet->size + * @param packet the packet to read the size of + */ +void NetworkRecv_ReadPacketSize(Packet *packet) +{ + packet->size = (uint16)packet->buffer[0]; + packet->size += (uint16)packet->buffer[1] << 8; +} + +uint8 NetworkRecv_uint8(NetworkClientState *cs, Packet *packet) +{ + uint8 n; + + if (!CanReadFromPacket(cs, packet, sizeof(n))) return 0; + + n = packet->buffer[packet->pos++]; + return n; +} + +uint16 NetworkRecv_uint16(NetworkClientState *cs, Packet *packet) +{ + uint16 n; + + if (!CanReadFromPacket(cs, packet, sizeof(n))) return 0; + + n = (uint16)packet->buffer[packet->pos++]; + n += (uint16)packet->buffer[packet->pos++] << 8; + return n; +} + +uint32 NetworkRecv_uint32(NetworkClientState *cs, Packet *packet) +{ + uint32 n; + + if (!CanReadFromPacket(cs, packet, sizeof(n))) return 0; + + n = (uint32)packet->buffer[packet->pos++]; + n += (uint32)packet->buffer[packet->pos++] << 8; + n += (uint32)packet->buffer[packet->pos++] << 16; + n += (uint32)packet->buffer[packet->pos++] << 24; + return n; +} + +uint64 NetworkRecv_uint64(NetworkClientState *cs, Packet *packet) +{ + uint64 n; + + if (!CanReadFromPacket(cs, packet, sizeof(n))) return 0; + + n = (uint64)packet->buffer[packet->pos++]; + n += (uint64)packet->buffer[packet->pos++] << 8; + n += (uint64)packet->buffer[packet->pos++] << 16; + n += (uint64)packet->buffer[packet->pos++] << 24; + n += (uint64)packet->buffer[packet->pos++] << 32; + n += (uint64)packet->buffer[packet->pos++] << 40; + n += (uint64)packet->buffer[packet->pos++] << 48; + n += (uint64)packet->buffer[packet->pos++] << 56; + return n; +} + +/** Reads a string till it finds a '\0' in the stream */ +void NetworkRecv_string(NetworkClientState *cs, Packet *p, char *buffer, size_t size) +{ + PacketSize pos; + char *bufp = buffer; + + /* Don't allow reading from a closed socket */ + if (HasClientQuit(cs)) return; + + pos = p->pos; + while (--size > 0 && pos < p->size && (*buffer++ = p->buffer[pos++]) != '\0') {} + + if (size == 0 || pos == p->size) { + *buffer = '\0'; + /* If size was sooner to zero then the string in the stream + * skip till the \0, so than packet can be read out correctly for the rest */ + while (pos < p->size && p->buffer[pos] != '\0') pos++; + pos++; + } + p->pos = pos; + + str_validate(bufp); +} + +#endif /* ENABLE_NETWORK */ -- cgit v1.2.3-54-g00ecf