rexy712/frnetlib
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

Performance improvements and fixes

Browse Source 
Greatly improvded fr::Packet>> performance.
Added buffer overflow protection to fr::Packet>>.
Added fr::Packet::reset_read_cursor to reset the packet data read position back to the beginning.
This commit is contained in:
Fred Nicolson 2017-01-22 12:11:17 +00:00
parent 64f35e2a92
commit f8aa22d223
1 changed files with 70 additions and 24 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

94
include/frnetlib/Packet.h
View File

@ -15,7 +15,11 @@ namespace fr
class Packet
{
public:
Packet() noexcept = default;
Packet() noexcept
: buffer_offset(0)
{
}
//Nasty constructor to allow things like Packet{1, 2, 3, "bob"}.
template <typename T, typename ...Args>
@ -25,14 +29,14 @@ namespace fr
}
template<typename T, typename ...Args>
void add(T const& part, Args &&...args)
inline void add(T const& part, Args &&...args)
{
*this << part;
add(std::forward<Args>(args)...);
}
template<typename T>
void add(T const part)
inline void add(T const part)
{
*this << part;
}
@ -102,8 +106,10 @@ namespace fr
*/
inline Packet &operator>>(bool &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
return *this;
}
@ -123,8 +129,10 @@ namespace fr
*/
inline Packet &operator>>(uint16_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohs(var);
return *this;
}
@ -134,8 +142,8 @@ namespace fr
*/
inline Packet &operator<<(uint32_t var)
{
buffer.resize(buffer.size() + sizeof(var));
var = htonl(var);
buffer.resize(buffer.size() + sizeof(var));
memcpy(&buffer[buffer.size() - sizeof(var)], &var, sizeof(var));
return *this;
}
@ -145,8 +153,10 @@ namespace fr
*/
inline Packet &operator>>(uint32_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohl(var);
return *this;
}
@ -167,8 +177,10 @@ namespace fr
*/
inline Packet &operator>>(uint64_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohll(var);
return *this;
}
@ -189,8 +201,10 @@ namespace fr
*/
inline Packet &operator>>(int16_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohs((uint16_t)var);
return *this;
}
@ -211,8 +225,10 @@ namespace fr
*/
inline Packet &operator>>(int32_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohl((uint32_t)var);
return *this;
}
@ -233,8 +249,10 @@ namespace fr
*/
inline Packet &operator>>(int64_t &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohll((uint64_t)var);
return *this;
}
@ -255,8 +273,10 @@ namespace fr
*/
inline Packet &operator>>(float &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);
var = ntohf(var);
return *this;
}
@ -277,8 +297,10 @@ namespace fr
*/
inline Packet &operator>>(double &var)
{
memcpy(&var, &buffer[0], sizeof(var));
buffer.erase(0, sizeof(var));
assert_data_remaining(sizeof(var));
memcpy(&var, &buffer[buffer_offset], sizeof(var));
buffer_offset += sizeof(var);;
var = ntohd(var);
return *this;
}
@ -311,8 +333,8 @@ namespace fr
uint32_t length = (uint32_t)var.length();
*this >> length;
var = buffer.substr(0, length);
buffer.erase(0, length);
var = buffer.substr(buffer_offset, length);
buffer_offset += sizeof(length);
return *this;
}
@ -333,10 +355,34 @@ namespace fr
inline void clear()
{
buffer.clear();
buffer_offset = 0;
}
/*!
* Resets the buffer read cursor back to the beginning
* of the packet.
*/
inline void reset_read_cursor()
{
buffer_offset = 0;
}
private:
/*!
* Checks that there's enough data in the buffer to extract
* a given number of bytes to prevent buffer overflows.
* Throws an exception if there is not enough space.
*
* @param required_space The number of bytes needed
*/
inline void assert_data_remaining(size_t required_space)
{
if(buffer_offset + required_space > buffer.size())
throw std::out_of_range("Not enough bytes remaining in packet to extract requested");
}
std::string buffer; //Packet data buffer
size_t buffer_offset; //Current read position
};
}