uIRC/src/uirc.c

/*
 *  This file is part of uIRC. (https://git.redxen.eu/caskd/uIRC)
 *  Copyright (c) 2019, 2020 Alex-David Denes
 *
 *  uIRC is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  any later version.
 *
 *  uIRC is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with uIRC.  If not, see <https://www.gnu.org/licenses/>.
*/
#include "uirc.h"

const char* const uirc_ircmd[] = {
    [PASS] = "PASS",
    [NICK] = "NICK",
    [USER] = "USER",
    [SERVER] = "SERVER",
    [OPER] = "OPER",
    [SERVICE] = "SERVICE",
    [QUIT] = "QUIT",
    [SQUIT] = "SQUIT",
    [JOIN] = "JOIN",
    [PART] = "PART",
    [MODE] = "MODE",
    [TOPIC] = "TOPIC",
    [NAMES] = "NAMES",
    [LIST] = "LIST",
    [INVITE] = "INVITE",
    [KICK] = "KICK",
    [VERSION] = "VERSION",
    [STATS] = "STATS",
    [LINKS] = "LINKS",
    [TIME] = "TIME",
    [CONNECT] = "CONNECT",
    [TRACE] = "TRACE",
    [ADMIN] = "ADMIN",
    [INFO] = "INFO",
    [SERVLIST] = "SERVLIST",
    [SQUERY] = "SQUERY",
    [PRIVMSG] = "PRIVMSG",
    [NOTICE] = "NOTICE",
    [MOTD] = "MOTD",
    [LUSERS] = "LUSERS",
    [WHO] = "WHO",
    [WHOIS] = "WHOIS",
    [WHOWAS] = "WHOWAS",
    [KILL] = "KILL",
    [PING] = "PING",
    [PONG] = "PONG",
    [ERROR] = "ERROR",
    [AWAY] = "AWAY",
    [REHASH] = "REHASH",
    [DIE] = "DIE",
    [RESTART] = "RESTART",
    [SUMMON] = "SUMMON",
    [USERS] = "USERS",
    [WALLOPS] = "WALLOPS",
    [USERHOST] = "USERHOST",
    [ISON] = "ISON"};

struct tagmapping {
	const char* name;
	IRC_Tag* assg;
};
int uirc_tokenize_message(IRC_Message* irc_msg, char** line)
{
	if (*line == NULL || irc_msg == NULL)
		return ERR_UIRC_NULL_ARGS;
	int ret;
	char *progr = *line, *command;
	if (*progr == '@') {
		char* tags;
		if ((tags = strtok_r(progr, " ", &progr)) != NULL) {
			if ((ret = tok_tags(tags, irc_msg)) < 0)
				return ret;
		} else
			return ERR_UIRC_INVALID_FORMAT;
	}
	if (*progr == ':') {
		char* prefix;
		if ((prefix = strtok_r(progr, " ", &progr)) != NULL) {
			if ((ret = tok_prefix(prefix, &irc_msg->name)) < 0)
				return ret;
		} else
			return ERR_UIRC_INVALID_FORMAT;
	}

	if ((command = strtok_r(NULL, " ", &progr)) != NULL) {
		if (isalpha(*command)) {
			if (!(irc_msg->cmd = uirc_ircmd_stoi(command)))
				return ERR_UIRC_UNKNOWN_TOKEN;
		} else if (isdigit(*command)) {
			if ((irc_msg->cmd = atoi(command)) == 0)
				return ERR_UIRC_UNKNOWN_TOKEN;
		} else {
			return ERR_UIRC_UNKNOWN_TOKEN;
		}
	} else {
		return ERR_UIRC_INVALID_FORMAT;
	}

	int i;
	for (i = 0; *progr != ':' && i < 14; i++) {
		if ((irc_msg->args[i] = strtok_r(NULL, " ", &progr)) == NULL)
			return ERR_UIRC_INVALID_FORMAT;
	}
	irc_msg->args[i] = NULL;
	if (*progr == ':')
		++progr;
	irc_msg->trailing = progr;
	return 1;
}
unsigned int uirc_ircmd_stoi(char* str)
{
	if (str == NULL)
		return ERR_UIRC_NULL_ARGS;
	for (unsigned short i = PASS; i <= ISON; i++) {
		if ((uirc_ircmd[i] != NULL) && (strcmp(uirc_ircmd[i], str) == 0))
			return i;
	}
	return ERR_UIRC_UNKNOWN_TOKEN;
}
int uirc_assm_mesg(char* buf, IRC_Message* mesg)
{
	if (buf == NULL || mesg == NULL)
		return ERR_UIRC_BUFFER_ERR;
	char* pos = buf;
	int cnt, ret;

	if ((ret = assm_tags(&pos, mesg)) < 0)
		return ret;
	if (mesg->name.nick != NULL || mesg->name.host != NULL) {
		if ((ret = assm_prefix(&pos, &mesg->name)) < 0)
			return ret;
	}
	if ((uirc_ircmd[mesg->cmd] != NULL) && ((cnt = sprintf(pos, "%s", uirc_ircmd[mesg->cmd])) > 0))
		pos += cnt;
	else
		return ERR_UIRC_GENERIC;
	for (unsigned int i = 0; i < 14 && mesg->args[i] != NULL; i++) {
		if ((cnt = sprintf(pos, " %s", mesg->args[i])) > 0)
			pos += cnt;
		else
			return ERR_UIRC_BUFFER_ERR;
	}
	if (mesg->trailing != NULL) {
		if ((cnt = sprintf(pos, " :%s", mesg->trailing)) > 0)
			pos += cnt;
		else
			return ERR_UIRC_GENERIC;
	}
	if ((cnt = sprintf(pos, "\r\n")) != 2)
		return ERR_UIRC_BUFFER_ERR;
	return 1;
}
int assm_tags(char** pos, IRC_Message* mesg)
{
	if (*pos == NULL || mesg == NULL)
		return ERR_UIRC_NULL_ARGS;
	const char* origpos = *pos;
	char* cpos = *pos;
	int cnt;
	const struct tagmapping tags[] = {
	    {.name = "time", .assg = &mesg->tags.time},
	    {.name = "account", .assg = &mesg->tags.account},
	    {.name = "batch", .assg = &mesg->tags.batch},
	    {.name = "label", .assg = &mesg->tags.label},
	    {.name = "msgid", .assg = &mesg->tags.msgid},
	    {.name = "multiline-concat", .assg = &mesg->tags.multiline_concat},
	    {.name = "typing", .assg = &mesg->tags.typing},
	    {.name = "react", .assg = &mesg->tags.react},
	    {.name = "reply", .assg = &mesg->tags.reply}};
	for (unsigned int i = 0; i < sizeof(tags) / sizeof(struct tagmapping); i++) {
		if ((*tags[i].assg).present) {
			if (cpos == origpos) {
				if (sprintf(cpos++, "@") != 1)
					return ERR_UIRC_BUFFER_ERR;
			} else {
				if (sprintf(cpos++, ";") != 1)
					return ERR_UIRC_BUFFER_ERR;
			}
			if ((*tags[i].assg).clientbound) {
				if (sprintf(cpos++, "+") != 1)
					return ERR_UIRC_BUFFER_ERR;
			}
			if ((*tags[i].assg).value != NULL)
				cnt = sprintf(cpos, "%s=%s", tags[i].name, (*tags[i].assg).value);
			else
				cnt = sprintf(cpos, "%s", tags[i].name);
			if (cnt > 0)
				cpos += cnt;
			else
				return ERR_UIRC_BUFFER_ERR;
		}
	}
	if (*origpos == '@') {
		if (sprintf(cpos++, " ") != 1)
			return ERR_UIRC_BUFFER_ERR;
	}
	*pos = cpos;
	return 1;
}
int tok_tags(char* msg, IRC_Message* mesg)
{
	if (msg == NULL || mesg == NULL)
		return ERR_UIRC_NULL_ARGS;
	char *cval, *cpos = msg, *ctag = NULL;
	bool clientbound;
	const struct tagmapping tags[] = {
	    {.name = "time", .assg = &mesg->tags.time},
	    {.name = "account", .assg = &mesg->tags.account},
	    {.name = "batch", .assg = &mesg->tags.batch},
	    {.name = "label", .assg = &mesg->tags.label},
	    {.name = "msgid", .assg = &mesg->tags.msgid},
	    {.name = "multiline-concat", .assg = &mesg->tags.multiline_concat},
	    {.name = "typing", .assg = &mesg->tags.typing},
	    {.name = "react", .assg = &mesg->tags.react},
	    {.name = "reply", .assg = &mesg->tags.reply}};
	if (*cpos == '@')
		cpos++;
	while ((ctag = strtok_r(NULL, "; ", &cpos)) != NULL) {
		clientbound = false;
		if (*ctag == '+') {
			ctag++;
			clientbound = true;
		}
		if ((cval = strchr(ctag, '=')) != NULL)
			*(cval++) = '\0';
		for (unsigned int i = 0; i < sizeof(tags) / sizeof(struct tagmapping); i++) {
			if (!strcmp(ctag, tags[i].name)) {
				if (cval != NULL)
					(*tags[i].assg).value = cval;
				(*tags[i].assg).clientbound = clientbound;
				(*tags[i].assg).present = true;
			}
		}
	}
	return 1;
}
int assm_prefix(char** str, IRC_User* usr)
{
	if (*str == NULL || usr == NULL)
		return ERR_UIRC_NULL_ARGS;
	int cnt;
	char* pos = *str;
	*(pos++) = ':';
	if (usr->nick == NULL && usr->user == NULL && usr->host != NULL) {
		if ((cnt = sprintf(pos, "%s", usr->host)) > 0)
			pos += cnt;
		else
			return ERR_UIRC_BUFFER_ERR;
	} else if (usr->nick != NULL) {
		if ((cnt = sprintf(pos, "%s", usr->nick)) > 0)
			pos += cnt;
		else
			return ERR_UIRC_BUFFER_ERR;
		if (usr->user != NULL) {
			if ((cnt = sprintf(pos, "!%s", usr->user)) > 0)
				pos += cnt;
			else
				return ERR_UIRC_BUFFER_ERR;
		}
		if (usr->host != NULL) {
			if ((cnt = sprintf(pos, "@%s", usr->host)) > 0)
				pos += cnt;
			else
				return ERR_UIRC_BUFFER_ERR;
		}
	} else
		return ERR_UIRC_NULL_ARGS;
	*(pos++) = ' ';
	*str = pos;
	return 1;
}
int tok_prefix(char* prefix, IRC_User* user)
{
	char* pos = (*prefix == ':') ? prefix + 1 : prefix;
	if ((user->host = strchr(pos, '@')) != NULL)
		*((char*)user->host++) = '\0';
	if ((user->user = strchr(pos, '!')) != NULL) /* RFC2812 says this cannot be here without the host but RFC1459 says it can, we accept both options */
		*((char*)user->user++) = '\0';
	if (*(user->nick = pos) == '\0') /* NOTE: This may be the server instead of a nick according to RFC2812, it is left to the library user to decide how to interpret this based on the context. */
		return ERR_UIRC_INVALID_FORMAT;
	return 1;
}