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// -*- mode: c++; c-basic-offset: 2; -*-
#include "common.hh"
#include <cstring>
#include "data.hh"
#include "package.hh"
size_t read_package(Package* pkg, uint8_t const* data, size_t max) {
if (max < 26) return 0;
size_t offset = 0;
pkg->id = read_u32(data + offset);
offset += 4;
pkg->timestamp.tv_sec = read_u64(data + offset);
offset += 8;
pkg->timestamp.tv_nsec = read_u32(data + offset);
offset += 4;
pkg->flags = read_u16(data + offset);
offset += 2;
pkg->source_port = read_u16(data + offset);
offset += 2;
pkg->target_port = read_u16(data + offset);
offset += 2;
auto len = read_u16(data + offset);
offset += 2;
if (offset + len + 2 > max) return 0;
pkg->source_host.assign(reinterpret_cast<char const*>(data) + offset, len);
offset += len;
len = read_u16(data + offset);
offset += 2;
if (offset + len > max) return 0;
pkg->target_host.assign(reinterpret_cast<char const*>(data) + offset, len);
offset += len;
return offset;
}
size_t write_package(Package const& pkg, uint8_t* data, size_t max) {
auto len = 26 + pkg.source_host.size() + pkg.target_host.size();
if (!data || max < len) {
return len;
}
write_u32(data, pkg.id);
write_u64(data + 4, pkg.timestamp.tv_sec);
write_u32(data + 12, pkg.timestamp.tv_nsec);
write_u16(data + 16, pkg.flags);
write_u16(data + 18, pkg.source_port);
write_u16(data + 20, pkg.target_port);
write_u16(data + 22, pkg.source_host.size());
memcpy(data + 24, pkg.source_host.data(), pkg.source_host.size());
write_u16(data + 24 + pkg.source_host.size(), pkg.target_host.size());
memcpy(data + 26 + pkg.source_host.size(),
pkg.target_host.data(), pkg.target_host.size());
return len;
}
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