MaxScale/gw_utils.c

/*
This file is distributed as part of the SkySQL Gateway. It 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,
version 2.

This program 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
this program; if not, write to the Free Software Foundation, Inc., 51
Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.

Copyright SkySQL Ab

*/

/*
03-06-2013
gateway utils
Massimiliano Pinto
*/

#include "gw.h"
#include "dcb.h"

///
// set ip address in sockect struct
///
void setipaddress(struct in_addr *a, char *p) {
	struct hostent *h = gethostbyname(p);
	if (h == NULL) {
		if ((a->s_addr = inet_addr(p)) == -1) {
			error("unknown or invalid address [%s]\n", p);
		}
	} else {
		memcpy(a, h->h_addr, h->h_length);
	}
}

int gw_daemonize(void) {
	pid_t pid;

	pid = fork();

	if (pid < 0) {
		fprintf(stderr, "fork() error %s\n", strerror(errno));
		exit(1);
	}

	if (pid != 0) {
		// exit from main
		exit(0);
	}

	if (setsid() < 0) {
		fprintf(stderr, "setsid() error %s\n", strerror(errno));
		exit(1);
	}
}

//////////////////////////////////////
// Generic read from filedescriptor
//////////////////////////////////////
int do_read_fd(int fd) {
	char buf[MAX_BUFFER_SIZE]="";
	int n;

	n = read(fd, buf, MAX_BUFFER_SIZE);

	if (n == 0) {
		fprintf(stderr, "Generic Socket EOF\n");
		return -1;
	}

	if (n < 0) {
		fprintf(stderr, "Read error: %i [%s]\n", errno, strerror(errno));
		if ((errno != EAGAIN) || (errno != EWOULDBLOCK))
			return -1;
		else
			return 0;
	}

#ifdef DEBUG_GATEWAY_READ
	fprintf(stderr, "socket %i, do_read %i bytes\n", fd, n);
#endif

	return n;
}

int do_read_dcb10(DCB *dcb) {
	char buf[MAX_BUFFER_SIZE]="";
	int n;
	n = read(dcb->fd, buf, 10);

	if (n == 0) {
		fprintf(stderr, "Read DCB Socket EOF\n");
		return -1;
	}

	if (n < 0) {
		fprintf(stderr, "ReadDcb error: %i [%s]\n", errno, strerror(errno));
		if ((errno != EAGAIN) || (errno != EWOULDBLOCK))
			return -1;
		else
			return 0;
	}

#ifdef GW_READ_DEBUG
	fprintf(stderr, "socket %i, do_read % i bytes, [%s]\n", dcb->fd, n, buf+5);
#endif

	return n;
}

int do_read_dcb(DCB *dcb) {
	char buf[MAX_BUFFER_SIZE]="";
	int n;
	n = read(dcb->fd, buf, MAX_BUFFER_SIZE);

	if (n == 0) {
		fprintf(stderr, "Read DCB Socket EOF\n");
		return -1;
	}

	if (n < 0) {
		fprintf(stderr, "ReadDcb error: %i [%s]\n", errno, strerror(errno));
		if ((errno != EAGAIN) || (errno != EWOULDBLOCK))
			return -1;
		else
			return 0;
	}

#ifdef GW_READ_DEBUG
	fprintf(stderr, "socket %i, do_read % i bytes, [%s]\n", dcb->fd, n, buf+5);
#endif

	return n;
}


int do_read_buffer10(DCB *dcb, uint8_t *buffer) {
	int n;
	n = read(dcb->fd, buffer, 10);

	if (n == 0 & (errno==EOF)) {
		fprintf(stderr, "ReadBuffer Socket EOF\n");
		return -1;
	}

	if (n < 0) {
		fprintf(stderr, "ReadBuffer error: %i [%s]\n", errno, strerror(errno));
		if ((errno != EAGAIN) || (errno != EWOULDBLOCK))
			return -1;
		else
			return 0;
	}

#ifdef GW_READ_DEBUG
	fprintf(stderr, "socket %i, do_read % i bytes\n", dcb->fd, n);
#endif

	return n;
}

int do_read_buffer(DCB *dcb, uint8_t *buffer) {
	int n;
	n = read(dcb->fd, buffer, MAX_BUFFER_SIZE);

	if (n == 0 & (errno==EOF)) {
		fprintf(stderr, "ReadBuffer Socket EOF\n");
		return -1;
	}

	if (n < 0) {
		fprintf(stderr, "ReadBuffer error: %i [%s]\n", errno, strerror(errno));
		if ((errno != EAGAIN) || (errno != EWOULDBLOCK))
			return -1;
		else
			return 0;
	}

#ifdef GW_READ_DEBUG
	fprintf(stderr, "socket %i, do_read % i bytes\n", dcb->fd, n);
#endif

	return n;
}

const char *gw_dcb_state2string (int state) {
	switch(state) {
		case DCB_STATE_ALLOC:
			return "DCB Allocated";
		case DCB_STATE_IDLE:
			return "DCB not yet in polling";
		case DCB_STATE_POLLING:
			return "DCB in the EPOLL";
		case DCB_STATE_PROCESSING:
			return "DCB processing event";
		case DCB_STATE_LISTENING:
			return "DCB for listening socket";
		default:
			return "DCB (unknown)";
	}
}