333 lines
9.4 KiB
C
333 lines
9.4 KiB
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 2013
|
|
*/
|
|
|
|
#include "mysql_client_server_protocol.h"
|
|
|
|
/*
|
|
* MySQL Protocol module for handling the protocol between the gateway
|
|
* and the backend MySQL database.
|
|
*
|
|
* Revision History
|
|
* Date Who Description
|
|
* 14/06/2013 Mark Riddoch Initial version
|
|
* 17/06/2013 Massimiliano Pinto Added Gateway To Backends routines
|
|
*/
|
|
|
|
static char *version_str = "V1.0.0";
|
|
|
|
int gw_create_backend_connection(DCB *client_dcb, SERVER *server, SESSION *in_session);
|
|
int gw_read_backend_event(DCB* dcb);
|
|
int gw_write_backend_event(DCB *dcb);
|
|
int gw_MySQLWrite_backend(DCB *dcb, GWBUF *queue);
|
|
int gw_error_backend_event(DCB *dcb);
|
|
static int gw_backend_close(DCB *dcb);
|
|
|
|
static GWPROTOCOL MyObject = {
|
|
gw_read_backend_event, /* Read - EPOLLIN handler */
|
|
gw_MySQLWrite_backend, /* Write - data from gateway */
|
|
gw_write_backend_event, /* WriteReady - EPOLLOUT handler */
|
|
gw_error_backend_event, /* Error - EPOLLERR handler */
|
|
NULL, /* HangUp - EPOLLHUP handler */
|
|
NULL, /* Accept */
|
|
gw_create_backend_connection, /* Connect */
|
|
gw_backend_close, /* Close */
|
|
NULL /* Listen */
|
|
};
|
|
|
|
/*
|
|
* Implementation of the mandatory version entry point
|
|
*
|
|
* @return version string of the module
|
|
*/
|
|
char *
|
|
version()
|
|
{
|
|
return version_str;
|
|
}
|
|
|
|
/*
|
|
* The module initialisation routine, called when the module
|
|
* is first loaded.
|
|
*/
|
|
void
|
|
ModuleInit()
|
|
{
|
|
fprintf(stderr, "Initial MySQL Client Protcol module.\n");
|
|
}
|
|
|
|
/*
|
|
* The module entry point routine. It is this routine that
|
|
* must populate the structure that is referred to as the
|
|
* "module object", this is a structure with the set of
|
|
* external entry points for this module.
|
|
*
|
|
* @return The module object
|
|
*/
|
|
GWPROTOCOL *
|
|
GetModuleObject()
|
|
{
|
|
return &MyObject;
|
|
}
|
|
|
|
|
|
//////////////////////////////////////////
|
|
//backend read event triggered by EPOLLIN
|
|
//////////////////////////////////////////
|
|
int gw_read_backend_event(DCB *dcb) {
|
|
int n;
|
|
MySQLProtocol *client_protocol = NULL;
|
|
|
|
if (dcb)
|
|
if(dcb->session)
|
|
client_protocol = SESSION_PROTOCOL(dcb->session, MySQLProtocol);
|
|
|
|
#ifdef GW_DEBUG_READ_EVENT
|
|
fprintf(stderr, "Backend ready! Read from Backend %i, write to client %i, client state %i\n", dcb->fd, dcb->session->client->fd, client_protocol->state);
|
|
#endif
|
|
|
|
if ((client_protocol->state == MYSQL_WAITING_RESULT) || (client_protocol->state == MYSQL_IDLE)) {
|
|
int w;
|
|
int b = -1;
|
|
int tot_b = -1;
|
|
uint8_t *ptr_buffer;
|
|
GWBUF *buffer, *head;
|
|
|
|
if (ioctl(dcb->fd, FIONREAD, &b)) {
|
|
fprintf(stderr, "Backend Ioctl FIONREAD error %i, %s\n", errno , strerror(errno));
|
|
} else {
|
|
//fprintf(stderr, "Backend IOCTL FIONREAD bytes to read = %i\n", b);
|
|
}
|
|
|
|
/*
|
|
* Read all the data that is available into a chain of buffers
|
|
*/
|
|
head = NULL;
|
|
while (b > 0)
|
|
{
|
|
int bufsize = b < MAX_BUFFER_SIZE ? b : MAX_BUFFER_SIZE;
|
|
if ((buffer = gwbuf_alloc(bufsize)) == NULL)
|
|
{
|
|
/* Bad news, we have run out of memory */
|
|
return 0;
|
|
}
|
|
GW_NOINTR_CALL(n = read(dcb->fd, GWBUF_DATA(buffer), bufsize); dcb->stats.n_reads++);
|
|
if (n < 0)
|
|
{
|
|
// if eerno == EAGAIN || EWOULDBLOCK is missing
|
|
// do the right task, not just break
|
|
break;
|
|
}
|
|
|
|
head = gwbuf_append(head, buffer);
|
|
|
|
// how many bytes left
|
|
b -= n;
|
|
}
|
|
|
|
// write the gwbuffer to client
|
|
dcb->session->client->func.write(dcb->session->client, head);
|
|
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
//////////////////////////////////////////
|
|
//backend write event triggered by EPOLLOUT
|
|
//////////////////////////////////////////
|
|
int gw_write_backend_event(DCB *dcb) {
|
|
//fprintf(stderr, ">>> gw_write_backend_event for %i\n", dcb->fd);
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Write function for backend DCB
|
|
*
|
|
* @param dcb The DCB of the client
|
|
* @param queue Queue of buffers to write
|
|
*/
|
|
int
|
|
gw_MySQLWrite_backend(DCB *dcb, GWBUF *queue)
|
|
{
|
|
int w, saved_errno = 0;
|
|
|
|
spinlock_acquire(&dcb->writeqlock);
|
|
if (dcb->writeq)
|
|
{
|
|
/*
|
|
* We have some queued data, so add our data to
|
|
* the write queue and return.
|
|
* The assumption is that there will be an EPOLLOUT
|
|
* event to drain what is already queued. We are protected
|
|
* by the spinlock, which will also be acquired by the
|
|
* the routine that drains the queue data, so we should
|
|
* not have a race condition on the event.
|
|
*/
|
|
dcb->writeq = gwbuf_append(dcb->writeq, queue);
|
|
dcb->stats.n_buffered++;
|
|
}
|
|
else
|
|
{
|
|
int len;
|
|
|
|
/*
|
|
* Loop over the buffer chain that has been passed to us
|
|
* from the reading side.
|
|
* Send as much of the data in that chain as possible and
|
|
* add any balance to the write queue.
|
|
*/
|
|
while (queue != NULL)
|
|
{
|
|
len = GWBUF_LENGTH(queue);
|
|
GW_NOINTR_CALL(w = write(dcb->fd, GWBUF_DATA(queue), len); dcb->stats.n_writes++);
|
|
saved_errno = errno;
|
|
if (w < 0)
|
|
{
|
|
break;
|
|
}
|
|
|
|
/*
|
|
* Pull the number of bytes we have written from
|
|
* queue with have.
|
|
*/
|
|
queue = gwbuf_consume(queue, w);
|
|
if (w < len)
|
|
{
|
|
/* We didn't write all the data */
|
|
}
|
|
}
|
|
/* Buffer the balance of any data */
|
|
dcb->writeq = queue;
|
|
if (queue)
|
|
{
|
|
dcb->stats.n_buffered++;
|
|
}
|
|
}
|
|
spinlock_release(&dcb->writeqlock);
|
|
|
|
if (queue && (saved_errno != EAGAIN || saved_errno != EWOULDBLOCK))
|
|
{
|
|
/* We had a real write failure that we must deal with */
|
|
return 1;
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
int gw_error_backend_event(DCB *dcb) {
|
|
MySQLProtocol *protocol = DCB_PROTOCOL(dcb, MySQLProtocol);
|
|
|
|
fprintf(stderr, "#### Handle Backend error function for %i\n", dcb->fd);
|
|
|
|
#ifdef GW_EVENT_DEBUG
|
|
if (event != -1) {
|
|
fprintf(stderr, ">>>>>> Backend DCB state %i, Protocol State %i: event %i, %i\n", dcb->state, dcb->proto_state, event & EPOLLERR, event & EPOLLHUP);
|
|
if(event & EPOLLHUP)
|
|
fprintf(stderr, "EPOLLHUP\n");
|
|
|
|
if(event & EPOLLERR)
|
|
fprintf(stderr, "EPOLLERR\n");
|
|
|
|
if(event & EPOLLPRI)
|
|
fprintf(stderr, "EPOLLPRI\n");
|
|
}
|
|
#endif
|
|
|
|
if (dcb->state != DCB_STATE_LISTENING) {
|
|
if (poll_remove_dcb(dcb) == -1) {
|
|
fprintf(stderr, "Backend poll_remove_dcb: from events check failed to delete %i, [%i]:[%s]\n", dcb->fd, errno, strerror(errno));
|
|
}
|
|
|
|
#ifdef GW_EVENT_DEBUG
|
|
fprintf(stderr, "Backend closing fd [%i]=%i, from events check\n", dcb->fd, protocol->fd);
|
|
#endif
|
|
if (dcb->fd) {
|
|
dcb->state = DCB_STATE_DISCONNECTED;
|
|
fprintf(stderr, "Freeing backend MySQL conn %p, %p\n", dcb->protocol, &dcb->protocol);
|
|
gw_mysql_close((MySQLProtocol **)&dcb->protocol);
|
|
fprintf(stderr, "Freeing backend MySQL conn %p, %p\n", dcb->protocol, &dcb->protocol);
|
|
}
|
|
}
|
|
}
|
|
|
|
/*
|
|
* Create a new MySQL backend connection.
|
|
*
|
|
* This routine performs the MySQL connection to the backend and fills the session->backends of the callier dcb
|
|
* with the new allocatetd dcb and adds the new socket to the poll set
|
|
*
|
|
* - backend dcb allocation
|
|
* - MySQL session data fetch
|
|
* - backend connection using data in MySQL session
|
|
*
|
|
* @param client_dcb The client DCB struct
|
|
* @return 0 on Success or 1 on Failure.
|
|
*/
|
|
|
|
int gw_create_backend_connection(DCB *backend, SERVER *server, SESSION *session) {
|
|
MySQLProtocol *ptr_proto = NULL;
|
|
MYSQL_session *s_data = NULL;
|
|
|
|
fprintf(stderr, "HERE, the server to connect is [%s]:[%i]\n", server->name, server->port);
|
|
|
|
backend->protocol = (MySQLProtocol *) calloc(1, sizeof(MySQLProtocol));
|
|
|
|
ptr_proto = (MySQLProtocol *)backend->protocol;
|
|
s_data = (MYSQL_session *)session->client->data;
|
|
|
|
|
|
fprintf(stderr, "HERE before connect, s_data is [%p]\n", s_data);
|
|
|
|
fprintf(stderr, "HERE before connect, username is [%s]\n", s_data->user);
|
|
|
|
// this is blocking until auth done
|
|
if (gw_mysql_connect(server->name, server->port, s_data->db, s_data->user, s_data->client_sha1, backend->protocol) == 0) {
|
|
memcpy(&backend->fd, &ptr_proto->fd, sizeof(backend->fd));
|
|
|
|
setnonblocking(backend->fd);
|
|
fprintf(stderr, "Connected to backend mysql server. fd is %i\n", backend->fd);
|
|
} else {
|
|
fprintf(stderr, "<<<< NOT Connected to backend mysql server!!!\n");
|
|
backend->fd = -1;
|
|
}
|
|
|
|
// if connected, it will be addeed to the epoll from the caller of connect()
|
|
|
|
if (backend->fd <= 0) {
|
|
perror("ERROR: epoll_ctl: backend sock");
|
|
return 1;
|
|
} else {
|
|
fprintf(stderr, "--> Backend conn added, bk_fd [%i], scramble [%s], is session with client_fd [%i]\n", backend->fd, ptr_proto->scramble, session->client->fd);
|
|
backend->state = DCB_STATE_POLLING;
|
|
//(backend->func).read = gw_read_backend_event;
|
|
//(backend->func).write = gw_MySQLWrite_backend;
|
|
//(backend->func).write_ready = gw_write_backend_event;
|
|
//(backend->func).error = gw_error_backend_event;
|
|
|
|
return backend->fd;
|
|
}
|
|
return -1;
|
|
}
|
|
|
|
static int
|
|
gw_backend_close(DCB *dcb)
|
|
{
|
|
dcb_close(dcb);
|
|
}
|