protocol.h #1

/*
 * protocol.h: Deal with the Perforce protocol.
 * $Header$
 */

#ifndef __PROTOCOL_H
#define __PROTOCOL_H

/*
 * PROTOCOL FORMAT
 *
 * The client and the server both speak mostly the same language.
 * Each sends to the other a series of packets with a number of
 * key/value pairs.  A packet contains a single check byte, followed
 * by a four-byte length, followed by the data.  The check byte is the
 * XOR of the length bytes; the length is little-endian, and specifies
 * the length of the data.  (Thus, the packet is (length+5) bytes
 * long.)
 *
 * A packet consists of an integral number of key/value pairs.  Each
 * pair consists of a null-terminated plain-text key.  The null is
 * followed by a four-byte little-endian length.  This word is
 * followed by data of exactly that many bytes, followed by another
 * null.
 */

#include "packet.h"
#include "pair.h"

/* Information we need to know to run the protocol. */
struct protocol_data
{
  /* Standard input and output of the client... */
  int client_in;
  int client_out;
  
  /* ...and of the server. */
  int server_in;
  int server_out;

  /* The authorized user's name. */
  const char *user;
};

/* Given a valid setup, speak the Perforce protocol to the client and
 * the server. */
void do_protocol(struct protocol_data *setup);

/* Convert packets to/from pairs. */
pair *packet_to_pair(const packet *data);
packet *pair_to_packet(const pair *pair);

/* Pull packets off the network, or push packets on.  The data packet
 * will include the entire packet, including the five-byte packet header. */
packet *read_packet(int fd);
int write_packet(int fd, const packet *data);

#endif /* __PROTOCOL_H */