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network.c
460 lines (344 loc) · 11 KB
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network.c
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#include <string.h>
#include <assert.h>
#include <stdlib.h>
#include <SDL2/SDL_net.h>
#include "network.h"
#include "debug.h"
#include "core.h"
#define READ_INT(ptr) (*((int*)(ptr)))
#define WRITE_INT(ptr,i) do { *((int*)(ptr)) = i; } while(0)
void messageDump(Message *msg, char *file_name)
{
FILE *fd = fopen(file_name, "wb");
assert(fd);
fwrite(msg->data, msg->length, 1, fd);
fclose(fd);
verbose1("messageDump -> %s\n", file_name);
}
/**
creates MSG_PACKAGE_INFO - basic version:
MSG_PACKAGE_INFO|msg->length|file_size|piece_size|file_name|author_name
@return NULL on error
Message* on success, dynamicaly allocated
*/
Message *messageCreatePackage(PackageInfo *package)
{
int tmp;
assert(package != NULL);
assert(package->file_size > 0);
assert(package->piece_size > 0);
// calculate required space for data
int len = 0;
if (package->file_name) len += strlen(package->file_name) +1;
if (package->author_name) len += strlen(package->author_name) +1;
len += sizeof(int); // enum MessageType
len += sizeof(int); // total message length
len += sizeof(int); // package->piece_size
len += sizeof(int); // package->file_size
verbose1("messageCreatePackage::len = %d\n", len);
Message *msg = calloc(len + sizeof(Message), 1);
assert(msg != NULL);
// copy package to message
verbose1("messageCreatePackage::copying package to message\n");
msg->length = len;
int pos = 0;
tmp = MSG_PACKAGE_INFO;
memcpy(msg->data + pos, &tmp, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &len, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &package->file_size, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &package->piece_size, sizeof(int));
pos += sizeof(int);
tmp = strlen(package->file_name) +1;
memcpy(msg->data + pos, package->file_name, tmp);
pos += tmp;
tmp = strlen(package->author_name) +1;
memcpy(msg->data + pos, package->author_name, tmp);
pos += tmp;
verbose1("messageCreatePackage::pos = %d\n", pos);
// debug msg to file
messageDump(msg, "messageCreatePackage.txt");
return msg;
}
/**
requires MSG_PACKAGE_INFO - basic version:
MSG_PACKAGE_INFO|msg->length|file_size|piece_size|file_name|author_name
@return NULL on error
Message* on success, dynamicaly allocated
*/
PackageInfo *messageParsePackage(Message *msg)
{
assert(msg);
messageDump(msg, "messageParsePackage.txt");
// allocate package
PackageInfo *pkg = calloc(sizeof(PackageInfo), 1);
assert(pkg);
// read items from message
int pos = 0;
pos += 4; // skip MessageType
pos += 4; // skip message length
pkg->file_size = READ_INT(msg->data + pos);
verbose1("messageParsePackage::file_size = %d\n", pkg->file_size);
pos += 4;
pkg->piece_size = READ_INT(msg->data + pos);
verbose1("messageParsePackage::piece_size = %d\n", pkg->piece_size);
pos += 4;
int len;
len = strlen(msg->data + pos);
verbose1("messageParsePackage::file_name::len = %d\n", len);
pkg->file_name = calloc(len + 1, 1);
assert(pkg->file_name);
strcpy(pkg->file_name, msg->data + pos);
verbose1("messageParsePackage::file_name = %s\n", pkg->file_name);
pos += len + 1;
len = strlen(msg->data + pos);
verbose1("messageParsePackage::author_name::len = %d\n", len);
pkg->author_name = calloc(len + 1, 1);
assert(pkg->author_name);
strcpy(pkg->author_name, msg->data + pos);
verbose1("messageParsePackage::author_name = %s\n", pkg->author_name);
pos += len + 1;
assert(pos == msg->length);
return pkg;
}
/**
creates MSG_DATA_REQUEST - request for one piece:
MSG_DATA_REQUEST|count|piece_index1|...
@param piece_index Array of pieces' indices
@param count Number of indices in piece_index
@return NULL on error
Message* on success, dynamicaly allocated
*/
Message *messageCreateDataRequest(int count, int *piece_index)
{
assert(count > 0);
assert(piece_index);
// allocate space
int len = (2 + count) * sizeof(int);
Message *msg = calloc(len + sizeof(Message), 1);
assert(msg);
verbose1("messageCreateDataRequest::copying indices to message\n");
msg->length = len;
int pos = 0;
int tmp = MSG_DATA_REQUEST;
memcpy(msg->data + pos, &tmp, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &count, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, piece_index, count * sizeof(int));
pos += count * sizeof(int);
assert(pos == msg->length);
verbose1("messageCreateDataRequest::msg created\n");
messageDump(msg, "messageCreateDataRequest.txt");
return msg;
}
/**
requires MSG_DATA_REQUEST - request for one piece:
MSG_DATA_REQUEST|count|piece_index1|...
@param msg Message to parse
@param piece_index Array to store pieces' indices
@return count Number of indices in piece_index
*/
int messageParseDataRequest(Message *msg, int *piece_index)
{
assert(msg);
assert(piece_index);
int count = 0;
int pos = 0;
pos += 4; // skip MessageType
count = READ_INT(msg->data + pos);
verbose1("messageParseDataRequest::count = %d\n", count);
pos += 4;
for (int i = 0; i < count; ++i) {
piece_index[i] = READ_INT(msg->data + pos);
verbose1("messageParseDataRequest::piece = %d\n", piece_index[i]);
pos += 4;
}
assert(pos == msg->length);
return count;
}
/**
creates MSG_DATA_REPLY - reply for one piece:
MSG_DATA_REPLY|piece_index|data_length|data
@param piece_index
@param data_length
@param data Bytes to send
@return NULL on error
Message* on success, dynamicaly allocated
*/
Message *messageCreateDataReply(int piece_index, const char *data, int data_length)
{
assert(piece_index >= 0);
assert(data);
assert(data_length > 0);
// allocate space
int len = 3 * sizeof(int) + data_length;
Message *msg = calloc(len + sizeof(Message), 1);
assert(msg);
verbose1("messageCreateDataReply::piece_index = %d\n", piece_index);
verbose1("messageCreateDataReply::data_length = %d\n", data_length);
verbose1("messageCreateDataReply::copying items to msg\n");
msg->length = len;
int pos = 0;
int tmp = MSG_DATA_REPLY;
memcpy(msg->data + pos, &tmp, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &piece_index, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, &data_length, sizeof(int));
pos += sizeof(int);
memcpy(msg->data + pos, data, data_length);
pos += data_length;
verbose1("messageCreateDataReply::pos, msg->length = %d, %d\n", pos, msg->length);
assert(pos == msg->length);
verbose1("messageCreateDataReply::msg created\n");
messageDump(msg, "messageCreateDataReply.txt");
return msg;
}
/**
requires MSG_DATA_REPLY - reply for one piece:
MSG_DATA_REPLY|piece_index|data_length|data
@param msg Message to parse
@param buf Memory to store data
@return piece_index
*/
int messageParseDataReply(Message *msg, char *buf)
{
assert(msg);
assert(buf);
messageDump(msg, "messageParseDataReply.txt");
int piece_index = 0;
int data_length = 0;
int pos = 0;
pos += 4; // skip MessageType
piece_index = READ_INT(msg->data + pos);
verbose1("messageParseDataReply::piece_index = %d\n", piece_index);
pos += 4;
data_length = READ_INT(msg->data + pos);
verbose1("messageParseDataReply::data_length = %d\n", data_length);
pos += 4;
memcpy(buf, msg->data + pos, data_length);
pos += data_length;
assert(pos == msg->length);
return piece_index;
}
Message *networkReceiveMessage(TCPsocket sock)
{
int result;
int msg_type = 0;
Message *msg = NULL;
// receive MessageType
result = SDLNet_TCP_Recv(sock, &msg_type, sizeof(int));
if(result <= 0) {
puts("thaat");
error();
}
verbose1("networkReceiveMessage::msg_type = %x\n", msg_type);
assert(msg_type == MSG_PACKAGE_INFO
|| msg_type == MSG_DATA_REQUEST
|| msg_type == MSG_DATA_REPLY);
// package info message
if (msg_type == MSG_PACKAGE_INFO) {
verbose1("networkReceiveMessage::MSG_PACKAGE_INFO\n");
// receive total length
int msg_len = 0;
result = SDLNet_TCP_Recv(sock, &msg_len, sizeof(int));
if (result <= 0)
error();
verbose1("networkReceiveMessage::msg_len = %d\n", msg_len);
// receive the rest of message
msg = calloc(msg_len + sizeof(Message), 1);
assert(msg);
msg->length = msg_len;
//msg->data[0] = msg_type;
//msg->data[4] = msg_len;
WRITE_INT(msg->data + 0, msg_type);
WRITE_INT(msg->data + 4, msg_len);
result = SDLNet_TCP_Recv(sock, msg->data + 8, msg_len - 2*sizeof(int));
if (result <= 0)
error();
verbose1("networkReceiveMessage::package received\n");
} else if (msg_type == MSG_DATA_REQUEST) {
verbose1("networkReceiveMessage::MSG_DATA_REQUEST\n");
// receive count of following items
int count = 0;
int msg_len = 0;
result = SDLNet_TCP_Recv(sock, &count, sizeof(int));
verbose1("result = %d\n", result);
if (result <= 0)
error();
verbose1("networkReceiveMessage::count = %d\n", count);
// receive the rest of message
msg_len = (count+2) * sizeof(int);
msg = calloc(msg_len + sizeof(Message), 1);
assert(msg);
msg->length = msg_len;
verbose1("networkReceiveMessage::msg->length = %d\n", msg->length);
//msg->data[0] = msg_type;
//msg->data[4] = count;
WRITE_INT(msg->data + 0, msg_type);
WRITE_INT(msg->data + 4, count);
result = SDLNet_TCP_Recv(sock, msg->data + 8, count * sizeof(int));
if (result <= 0)
error();
verbose1("networkReceiveMessage::package received\n");
messageDump(msg, "networkReceiveMessage_MSG_DATA_REQUEST.txt");
} else if (msg_type == MSG_DATA_REPLY) {
verbose1("networkReceiveMessage::MSG_DATA_REPLY\n");
// receive piece_index
int piece_index = -1;
result = SDLNet_TCP_Recv(sock, &piece_index, sizeof(int));
verbose1("result = %d\n", result);
if (result <= 0) {
puts("_381_");
error();
}
verbose1("networkReceiveMessage::piece_index = %d\n", piece_index);
// receive length of data
int data_len = 0;
result = SDLNet_TCP_Recv(sock, &data_len, sizeof(int));
verbose1("result = %d\n", result);
if (result <= 0)
error();
verbose1("networkReceiveMessage::data_len = %d\n", data_len);
// alloc struct for data
int msg_len = 3 * sizeof(int) + data_len;
msg = calloc(msg_len + sizeof(Message), 1);
assert(msg);
msg->length = msg_len;
verbose1("networkReceiveMessage::msg->length = %d\n", msg->length);
//msg->data[0] = msg_type; // zly typ
//msg->data[4] = piece_index;
//msg->data[8] = data_len;
WRITE_INT(msg->data + 0, msg_type);
WRITE_INT(msg->data + 4, piece_index);
WRITE_INT(msg->data + 8, data_len);
// receive data
result = SDLNet_TCP_Recv(sock, msg->data + 12, data_len);
if (result <= 0)
error();
verbose1("networkReceiveMessage::package received\n");
messageDump(msg, "networkReceiveMessage_MSG_DATA_REPLY.txt");
}
return msg;
}
int networkSendMessage(TCPsocket sock, Message *msg)
{
return SDLNet_TCP_Send(sock, msg->data, msg->length);
}
/**
@param nbo_ip IP in network byte order
(can be obtained from SDL IPaddress)
@return char* dynamically allocated string, like "127.0.0.1"
*/
char *nboipToString(int nbo_ip)
{
char *s = calloc(16, 1); // max possible length
assert(s);
char ip[4];
memcpy(ip, &nbo_ip, sizeof(int));
sprintf(s, "%d.%d.%d.%d", ip[0], ip[1], ip[2], ip[3]);
return s;
}