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#include "mctypes.h"
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
varint to_varint(unsigned int x)
{
varint n = NULL;
unsigned int size = 0;
while (1) {
n = reallocarray(n, size, sizeof(u_int8_t));
if(n == NULL){
exit(1);
}
n[size] = x & 0x7F;
x >>= 7;
if (x == 0)
return n;
n[size] |= 0x80;
size++;
}
return n;
}
int from_varint(const varint x)
{
unsigned int offset = 0;
unsigned int res = 0;
do {
if (offset == 5)
exit(EXIT_FAILURE);
res |= (x[offset] & 0x7F) << offset * 7;
offset++;
} while ((x[offset-1] & 0x80) != 0);
return (int) res;
}
size_t size_varint(const varint x)
{
size_t v_size;
for (v_size = 1; (x[v_size - 1] & 0x80) != 0; v_size++);
return v_size;
}
size_t serialize_handshake(handshake hs, void **buf)
{
size_t size = 0;
size_t varint_s;
// *buf = malloc(size);
varint_s = size_varint(hs.protocol_version);
*buf = realloc(*buf, size + varint_s);
memmove(*buf + size, hs.protocol_version, varint_s);
size += varint_s;
varint_s = size_varint(hs.server_address.length);
*buf = realloc(*buf, size + varint_s);
memcpy(*buf + size, hs.server_address.length, varint_s);
size += varint_s;
*buf = realloc(*buf, size + from_varint(hs.server_address.length));
memcpy(*buf + size, hs.server_address.content,
from_varint(hs.server_address.length));
size += from_varint(hs.server_address.length);
*buf = realloc(*buf, size + sizeof(unsigned short));
memcpy(*buf + size, &hs.server_port, sizeof(unsigned short));
size += sizeof(unsigned short);
varint_s = size_varint(hs.next_state);
*buf = realloc(*buf, size + varint_s);
memcpy(*buf + size, hs.next_state, varint_s);
size += varint_s;
return size;
}
size_t serialize_packet(const packet p, void **buf)
{
size_t v_size = size_varint(p.length);
size_t p_size = from_varint(p.length) + v_size; // total size of packet
size_t size = 0;
*buf = malloc(p_size);
memcpy(*buf, p.length, v_size);
size += v_size;
for (v_size = 1; (p.id[v_size - 1] & 0x80) != 0; v_size++);
memcpy(*buf + size, p.id, v_size);
size += v_size;
memcpy(*buf + size, p.data, from_varint(p.length) - v_size);
return p_size;
}
varint deserialize_varint(void **raw)
{
varint v = NULL;
// void *f = *raw;
unsigned short i = 0;
do {
v = reallocarray(v, i+1, sizeof(u_int8_t));
if(v == NULL){
exit(1);
}
memcpy(v+i, *raw, sizeof(u_int8_t));
(*raw)++;
i++;
} while ((v[i-1] & 0x80) != 0);
// free(f);
return v;
}
string deserialize_string(void **raw)
{
string s;
// void *f = *raw;
s.length = deserialize_varint(raw);
s.content = malloc(from_varint(s.length));
memcpy(s.content, *raw, from_varint(s.length));
return s;
};
void free_packet(packet p)
{
free(p.length);
free(p.id);
free(p.data);
}
void free_handshake(handshake h)
{
free(h.protocol_version);
free(h.server_address.length);
free(h.next_state);
}
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