/*************************************************************************
* (C) 2010 AITNET ltd - Sofia/Bulgaria - <misho@aitbg.com>
*  by Michael Pounov <misho@openbsd-bg.org>
*
* $Author: misho $
* $Id: cli.c,v 1.1 2010/06/18 01:48:06 misho Exp $
*
*************************************************************************/
#include "global.h"


/*
 * rpc_cli_openClient() Connect to RPC Server
 * @ProgID = ProgramID for RPC session request
 * @ProcID = ProcessID for RPC session request
 * @family = Family socket type, AF_INET or AF_INET6
 * @csHost = Host name or IP address for bind server
 * @Port = Port for bind server, if Port == 0 default port is selected
 * return: NULL == error or !=NULL connection to RPC server established
 */
rpc_cli_t *
rpc_cli_openClient(u_int ProgID, u_int ProcID, u_short family, const char *csHost, u_short Port)
{
	rpc_cli_t *cli = NULL;
	struct hostent *host = NULL;
	struct sockaddr_in sin;
	struct sockaddr_in6 sin6;

	if (!csHost || (family != AF_INET && family != AF_INET6)) {
		rpc_SetErr(EINVAL, "Error:: Invalid parameters can`t connect to RPC server ...\n");
		return NULL;
	}
	if (!Port)
		Port = RPC_DEFPORT;
	if (csHost) {
		host = gethostbyname2(csHost, family);
		if (!host) {
			rpc_SetErr(h_errno, "Error:: %s\n", hstrerror(h_errno));
			return NULL;
		}
	}
	switch (family) {
		case AF_INET:
			memset(&sin, 0, sizeof sin);
			sin.sin_len = sizeof sin;
			sin.sin_family = family;
			sin.sin_port = htons(Port);
			if (csHost)
				memcpy(&sin.sin_addr, host->h_addr, host->h_length);
			break;
		case AF_INET6:
			memset(&sin6, 0, sizeof sin6);
			sin6.sin6_len = sizeof sin6;
			sin6.sin6_family = family;
			sin6.sin6_port = htons(Port);
			if (csHost)
				memcpy(&sin6.sin6_addr, host->h_addr, host->h_length);
			break;
		default:
			rpc_SetErr(EINVAL, "Error:: Invalid parameters can`t connect to RPC server ...\n");
			return NULL;
	}

	cli = malloc(sizeof(rpc_cli_t));
	if (!cli) {
		LOGERR;
		return NULL;
	} else
		memset(cli, 0, sizeof(rpc_cli_t));
	cli->cli_parent = malloc(sizeof(rpc_sess_t));
	if (!cli->cli_parent) {
		LOGERR;
		free(cli);
		return NULL;
	} else {
		((rpc_sess_t*) cli->cli_parent)->sess_version = RPC_VERSION;
		((rpc_sess_t*) cli->cli_parent)->sess_program = ProgID;
		((rpc_sess_t*) cli->cli_parent)->sess_process = ProcID;
	}

	if (family == AF_INET)
		memcpy(&cli->cli_sa, &sin, sizeof cli->cli_sa);
	else
		memcpy(&cli->cli_sa, &sin6, sizeof cli->cli_sa);
	cli->cli_sock = socket(family, SOCK_STREAM, 0);
	if (cli->cli_sock == -1) {
		LOGERR;
		free(cli->cli_parent);
		free(cli);
		return NULL;
	}
	if (connect(cli->cli_sock, &cli->cli_sa, sizeof cli->cli_sa) == -1) {
		LOGERR;
		free(cli->cli_parent);
		free(cli);
		return NULL;
	}

	return cli;
}

/*
 * rpc_cli_closeClient() Close connection to RPC server and free resources
 * @cli = RPC Client session
 * return: none
 */
void
rpc_cli_closeClient(rpc_cli_t * __restrict cli)
{
	if (!cli) {
		rpc_SetErr(EINVAL, "Error:: Can`t close connection because parameter is null!\n");
		return;
	}

	shutdown(cli->cli_sock, SHUT_RDWR);
	close(cli->cli_sock);

	if (cli->cli_parent)
		free(cli->cli_parent);
	free(cli);
	cli = NULL;
}


/*
 * rpc_cli_execCall() Execute RPC call
 * @cli = RPC Client session
 * @csModule = Module name, if NULL self binary
 * @csFunc = Function name for execute
 * @in_argc = IN count of arguments
 * @in_vals = IN RPC call array of rpc values
 * @out_argc = OUT returned count of arguments
 * @out_vals = OUT returned array of rpc values, must be free after use (see rpc_cli_freeVals())
 * return: -1 error or != -1 ok result
 */
int
rpc_cli_execCall(rpc_cli_t *cli, const char *csModule, const char *csFunc, int in_argc, 
		rpc_val_t * __restrict in_vals, int *out_argc, rpc_val_t ** __restrict out_vals)
{
	fd_set fds;
	u_char buf[BUFSIZ], str[MAXPATHLEN + UCHAR_MAX + 1], *data;
	struct tagRPCCall *rpc = (struct tagRPCCall*) buf;
	struct tagRPCRet *rrpc;
	int ret = 0, Limit = 0;
	register int i;
	rpc_val_t *v;
	struct timeval tv = { DEF_CLI_TIMEOUT, 0 };

	FD_ZERO(&fds);
	memset(buf, 0, BUFSIZ);
	memset(str, 0, MAXPATHLEN + UCHAR_MAX + 1);
	if (!cli || !csFunc || (in_argc && !in_vals)) {
		rpc_SetErr(EINVAL, "Error:: Can`t execute call because parameter is null or invalid!\n");
		return -1;
	}
	if (csModule)
		strlcpy((char*) str, csModule, MAXPATHLEN + UCHAR_MAX + 1);
	strlcat((char*) str, "__", MAXPATHLEN + UCHAR_MAX + 1);
	strlcat((char*) str, csFunc, MAXPATHLEN + UCHAR_MAX + 1);

	memcpy(&rpc->call_session, cli->cli_parent, sizeof rpc->call_session);
	rpc->call_argc = in_argc;
	rpc->call_tag = crcFletcher16((u_short*) str, (MAXPATHLEN + UCHAR_MAX + 1) / 2);
	rpc->call_hash = hash_fnv((char*) str, MAXPATHLEN + UCHAR_MAX + 1);
	Limit = sizeof(struct tagRPCCall);
	if (in_argc) {
		v = (rpc_val_t*) (buf + sizeof(struct tagRPCCall));
		memcpy(v, in_vals, in_argc * sizeof(rpc_val_t));
		Limit += in_argc * sizeof(rpc_val_t);
		data = (u_char*) v + in_argc * sizeof(rpc_val_t);
		for (i = 0; i < in_argc; i++) {
			switch (in_vals[i].val_type) {
				case buffer:
					if (Limit + in_vals[i].val_len > BUFSIZ) {
						ret = -7;
						break;
					}

					memcpy(data, in_vals[i].val.buffer, in_vals[i].val_len);
					v[i].val.buffer = (uint8_t*) ((void*) data - (void*) v);
					data += in_vals[i].val_len;
					Limit += in_vals[i].val_len;
					break;
				case string:
					if (Limit + in_vals[i].val_len + 1 > BUFSIZ) {
						ret = -7;
						break;
					}

					memcpy(data, in_vals[i].val.string, in_vals[i].val_len);
					v[i].val.string = (int8_t*) ((void*) data - (void*) v);
					data += in_vals[i].val_len;
					Limit += in_vals[i].val_len;
					break;
				case array:
					if (Limit + in_vals[i].val_len > BUFSIZ) {
						ret = -7;
						break;
					}

					memcpy(data, in_vals[i].val.array, in_vals[i].val_len);
					v[i].val.array = (int8_t**) ((void*) data - (void*) v);
					data += in_vals[i].val_len;
					Limit += in_vals[i].val_len;
					break;
				default:
					break;
			}
		}
		if (ret < 0) {
			rpc_SetErr(EMSGSIZE, "Error:: in prepare RPC packet (-7) ...\n");
			return ret;
		}
	}
	if ((ret = send(cli->cli_sock, buf, Limit, 0)) == -1) {
		LOGERR;
		return -1;
	}
	if (ret != Limit) {
		rpc_SetErr(EBADMSG, "Error:: in send RPC request, should be send %d bytes, really is %d\n", 
				Limit, ret);
		return -9;
	}

	FD_SET(cli->cli_sock, &fds);
	if ((ret = select(cli->cli_sock + 1, &fds, NULL, NULL, &tv)) < 1) {
		if (ret) {
			LOGERR;
		} else
			rpc_SetErr(ETIMEDOUT, "Error:: timeout, no return from RPC server?\n");
		return -1;
	}
	memset(buf, 0, BUFSIZ);
	if ((ret = recv(cli->cli_sock, buf, BUFSIZ, 0)) == -1) {
		LOGERR;
		return -3;
	}
	if (!ret)	// receive EOF
		return 0;
	if (ret < sizeof(struct tagRPCCall)) {
		rpc_SetErr(EMSGSIZE, "Error:: too short RPC packet ...\n");
		return -4;
	} else
		rrpc = (struct tagRPCRet*) buf;
	// check RPC packet session info
	if (memcmp(&rrpc->ret_session, cli->cli_parent, sizeof rrpc->ret_session)) {
		rpc_SetErr(EINVAL, "Error:: get invalid RPC session ...\n");
		return -5;
	}
	if (rrpc->ret_retcode < 0 && rrpc->ret_errno) {
		rpc_SetErr(rrpc->ret_errno, "Error::Server side: %s\n", strerror(rrpc->ret_errno));
		return -6;
	}
	// RPC is OK! Go decapsulate variables ...
	if (rrpc->ret_argc) {
		*out_argc = rrpc->ret_argc;
		*out_vals = calloc(rrpc->ret_argc, sizeof(rpc_val_t));
		if (!*out_vals) {
			LOGERR;
			*out_argc = 0;
			return -1;
		} else
			Limit = rrpc->ret_argc * sizeof(rpc_val_t);
		memcpy(*out_vals, buf + sizeof(struct tagRPCRet), Limit);
		// RPC received variables types OK!
		data = (u_char*) buf + sizeof(struct tagRPCRet) + Limit;
		for (i = 0; i < rrpc->ret_argc; i++)
			switch ((*out_vals)[i].val_type) {
				case buffer:
					(*out_vals)[i].val.buffer = malloc((*out_vals)[i].val_len);
					if (!(*out_vals)[i].val.buffer) {
						rpc_SetErr(errno, "Error:: in prepare RPC reply ...\n");
						free(*out_vals);
						*out_vals = NULL;
						*out_argc = 0;
						return -1;
					} else
						memcpy((*out_vals)[i].val.buffer, data, (*out_vals)[i].val_len);
				       	data += (*out_vals)[i].val_len;
					break;
				case string:
					(*out_vals)[i].val.string = (int8_t*) strdup((char*) data);
					if (!(*out_vals)[i].val.string) {
						rpc_SetErr(errno, "Error:: in prepare RPC reply ...\n");
						free(*out_vals);
						*out_vals = NULL;
						*out_argc = 0;
						return -1;
					}
				       	data += (*out_vals)[i].val_len + 1;
					break;
				case array:
					(*out_vals)[i].val.array = malloc((*out_vals)[i].val_len);
					if (!(*out_vals)[i].val.array) {
						rpc_SetErr(errno, "Error:: in prepare RPC reply ...\n");
						free(*out_vals);
						*out_vals = NULL;
						*out_argc = 0;
						return -1;
					} else
						memcpy((*out_vals)[i].val.array, data, (*out_vals)[i].val_len);
				       	data += (*out_vals)[i].val_len;
					break;
				default:
					break;
			}
	} else {
		*out_argc = 0;
		*out_vals = NULL;
	}

	return rrpc->ret_retcode;
}

/*
 * rpc_cli_freeVals() Free rpc_val_t array returned from RPC call
 * @args = Number of arguments in array
 * @vals = Value elements
 * return: none
 */
inline void
rpc_cli_freeVals(int args, rpc_val_t *vals)
{
	register int i;

	if (!vals)
		return;

	for (i = 0; i < args; i++)
		RPC_FREE_VAL(&vals[i]);

	free(vals);
	vals = NULL;
}