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in utils.c see line 88 for modifications

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This commit is contained in:
Massimiliano Pinto
2013-06-12 15:15:09 +02:00
parent a70974d8a1 08549ad5ae
commit 2cf646d948
6 changed files with 330 additions and 164 deletions
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6
core/Makefile
View File

@ -16,7 +16,8 @@
CC=cc CC=cc
CFLAGS=-c -I/usr/include -I../include CFLAGS=-c -I/usr/include -I../include
SRCS= atomic.c buffer.c spinlock.c gateway.c gateway_mysql_protocol.c gw_utils.c utils.c SRCS= atomic.c buffer.c spinlock.c gateway.c gateway_mysql_protocol.c gw_utils.c \
utils.c dcb.c
OBJ=$(SRCS:.c=.o) OBJ=$(SRCS:.c=.o)
LIBS=-lssl LIBS=-lssl
@ -25,3 +26,6 @@ gateway: $(OBJ)
.c.o: .c.o:
$(CC) $(CFLAGS) $< -o $@ $(CC) $(CFLAGS) $< -o $@
clean:
rm -f $(OBJ) gateway

174
core/dcb.c Normal file
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@ -0,0 +1,174 @@
/*
* 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
*/
/*
* dcb.c - Descriptor Control Block generic functions
*
* Revision History
*
* Date Who Description
* 12/06/13 Mark Riddoch Initial implementation
*
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <dcb.h>
#include <spinlock.h>
static DCB *allDCBs = NULL; /* Diagnotics need a list of DCBs */
static SPINLOCK *dcbspin = NULL;
/*
* Allocate a new DCB.
*
* This routine performs the generic initialisation on the DCB before returning
* the newly allocated DCB.
*
* @return A newly allocated DCB or NULL if non could be allocated.
*/
DCB *
alloc_dcb()
{
DCB *rval;
if (dcbspin == NULL)
{
if ((dcbspin = malloc(sizeof(SPINLOCK))) == NULL)
return NULL;
spinlock_init(dcbspin);
}
if ((rval = malloc(sizeof(DCB))) == NULL)
{
return NULL;
}
spinlock_init(&rval->writeqlock);
rval->writeq = NULL;
rval->state = DCB_STATE_ALLOC;
memset(&rval->stats, 0, sizeof(DCBSTATS)); // Zero the statistics
spinlock_acquire(dcbspin);
if (allDCBs == NULL)
allDCBs = rval;
else
{
DCB *ptr = allDCBs;
while (ptr->next)
ptr = ptr->next;
ptr->next = rval;
}
spinlock_release(dcbspin);
return rval;
}
/*
* Free a DCB and remove it from the chain of all DCBs
*
* @param dcb THe DCB to free
*/
void
free_dcb(DCB *dcb)
{
dcb->state = DCB_STATE_FREED;
/* First remove this DCB from the chain */
spinlock_acquire(dcbspin);
if (allDCBs == dcb)
allDCBs = dcb->next;
else
{
DCB *ptr = allDCBs;
while (ptr && ptr->next != dcb)
ptr = ptr->next;
if (ptr)
ptr->next = dcb->next;
}
spinlock_release(dcbspin);
free(dcb);
}
/*
* Diagnostic to print a DCB
*
* @param dcb The DCB to print
*
*/
void
printDCB(DCB *dcb)
{
(void)printf("DCB: 0x%x\n", (void *)dcb);
(void)printf("\tDCB state: %s\n", gw_dcb_state2string(dcb->state));
(void)printf("\tQueued write data: %d\n", gwbuf_length(dcb->writeq));
(void)printf("\tStatistics:\n");
(void)printf("\t\tNo. of Reads: %d\n", dcb->stats.n_reads);
(void)printf("\t\tNo. of Writes: %d\n", dcb->stats.n_writes);
(void)printf("\t\tNo. of Accepts: %d\n", dcb->stats.n_accepts);
}
/*
* Diagnostic to print all DCB allocated in the system
*
*/
void printAllDCBs()
{
DCB *dcb;
if (dcbspin == NULL)
{
if ((dcbspin = malloc(sizeof(SPINLOCK))) == NULL)
return;
spinlock_init(dcbspin);
}
spinlock_acquire(dcbspin);
dcb = allDCBs;
while (dcb)
{
printDCB(dcb);
dcb = dcb->next;
}
spinlock_release(dcbspin);
}
/*
* Return a string representation of a DCB state.
*
* @param state The DCB state
* @return String representation of the state
*
*/
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";
case DCB_STATE_DISCONNECTED:
return "DCB socket closed";
default:
return "DCB (unknown)";
}
}

2
core/gateway.c
View File

@ -265,7 +265,7 @@ int main(int argc, char **argv) {
if (events[n].events & EPOLLOUT) { if (events[n].events & EPOLLOUT) {
if (dcb->state != DCB_STATE_LISTENING) { if (dcb->state != DCB_STATE_LISTENING) {
fprintf(stderr, "CALL the WRITE pointer\n"); fprintf(stderr, "CALL the WRITE pointer\n");
(dcb->func).write(dcb, epollfd); (dcb->func).write_ready(dcb, epollfd);
fprintf(stderr, ">>> CALLED the WRITE pointer\n"); fprintf(stderr, ">>> CALLED the WRITE pointer\n");
} }
} }

18
core/gw_utils.c
View File

@ -191,21 +191,3 @@ int do_read_buffer(DCB *dcb, uint8_t *buffer) {
return n; 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";
case DCB_STATE_DISCONNECTED:
return "DCB socket closed";
default:
return "DCB (unknown)";
}
}

258
core/utils.c
View File

@ -61,12 +61,10 @@ int gw_read_backend_event(DCB *dcb, int epfd) {
if ((client_protocol->state == MYSQL_WAITING_RESULT) || (client_protocol->state == MYSQL_IDLE)) { if ((client_protocol->state == MYSQL_WAITING_RESULT) || (client_protocol->state == MYSQL_IDLE)) {
struct epoll_event new_event; struct epoll_event new_event;
int w; int w;
int count_reads = 0;
int count_writes = 0;
uint8_t buffer[MAX_BUFFER_SIZE];
int b = -1; int b = -1;
int tot_b = -1; int tot_b = -1;
uint8_t *ptr_buffer; uint8_t *ptr_buffer;
GWBUF *buffer, *head;
if (ioctl(dcb->fd, FIONREAD, &b)) { if (ioctl(dcb->fd, FIONREAD, &b)) {
fprintf(stderr, "Backend Ioctl FIONREAD error %i, %s\n", errno , strerror(errno)); fprintf(stderr, "Backend Ioctl FIONREAD error %i, %s\n", errno , strerror(errno));
@ -74,91 +72,34 @@ int gw_read_backend_event(DCB *dcb, int epfd) {
fprintf(stderr, "Backend IOCTL FIONREAD bytes to read = %i\n", b); fprintf(stderr, "Backend IOCTL FIONREAD bytes to read = %i\n", b);
} }
// detect pending data in the buffer for client write /*
if (dcb->session->client->buff_bytes > 0) { * Read all the data that is available into a chain of buffers
*/
fprintf(stderr, "*********** Read backend says there are pending writes for %i bytes\n", dcb->session->client->buff_bytes); head = NULL;
// read data from socket, assume no error here (quick) and put it into the DCB second buffer while (b > 0)
GW_NOINTR_CALL(n = read(dcb->fd, buffer, b < MAX_BUFFER_SIZE ? b : MAX_BUFFER_SIZE); count_reads++); {
int bufsize = b < MAX_BUFFER_SIZE ? b : MAX_BUFFER_SIZE;
memcpy(&dcb->session->client->second_buff_bytes, &n, sizeof(int)); if ((buffer = gwbuf_alloc(bufsize)) == NULL)
fprintf(stderr, "#### second buff_bytes set to %i\n", dcb->session->client->second_buff_bytes); {
/* Bad news, we have run out of memory */
memcpy(dcb->session->client->second_buffer, buffer, n); return 0;
fprintf(stderr, "#### filled memory second buffer!\n"); }
dcb->session->client->second_buffer_ptr = dcb->session->client->second_buffer; GW_NOINTR_CALL(n = read(dcb->fd, GWBUF_DATA(buffer), bufsize); dcb->stats.n_reads++);
return 1;
}
// else, no pending data
tot_b = b;
// read all the data, without using multiple buffers, only one
while (b > 0) {
GW_NOINTR_CALL(n = read(dcb->fd, buffer, b < MAX_BUFFER_SIZE ? b : MAX_BUFFER_SIZE); count_reads++);
fprintf (stderr, "Read %i/%i bytes done, n. reads = %i, %i. Next could be write\n", n, b, count_reads, errno);
if (n < 0) { if (n < 0) {
if ((errno != EAGAIN) || (errno != EWOULDBLOCK)) // if eerno == EAGAIN || EWOULDBLOCK is missing
return 0;
else // do the rigth task, not just break
return 1; break;
} else {
b = b - n;
} }
head = gwbuf_append(head, buffer);
// how many bytes left
b = b - n;
} }
ptr_buffer = buffer;
if(n >2) dcb->session->client->func.write(dcb->session->client, head);
fprintf(stderr, ">>> The READ BUFFER last 2 byte [%i][%i]\n", buffer[n-2], buffer[n-1]);
// write all the data
// if write fails for EAGAIN or EWOULDBLOCK, copy the data into the dcb buffer
while (n >0) {
GW_NOINTR_CALL(w = write(dcb->session->client->fd, ptr_buffer, n); count_writes++);
fprintf (stderr, "Write Cycle %i, %i of %i bytes done, errno %i\n", count_writes, w, n, errno);
if (w > 2)
fprintf(stderr, "<<< writed BUFFER last 2 byte [%i][%i]\n", ptr_buffer[w-2], ptr_buffer[w-1]);
if (w < 0) {
if ((errno != EAGAIN) || (errno != EWOULDBLOCK)) {
break;
} else {
fprintf(stderr, "<<<< Write to client not completed for %i bytes!\n", n);
if (dcb->session->client) {
fprintf(stderr, "<<<< Try to set buff_bytes!\n");
memcpy(&dcb->session->client->buff_bytes, &n, sizeof(int));
fprintf(stderr, "<<<< buff_bytes set to %i\n", dcb->session->client->buff_bytes);
fprintf(stderr, "<<<< Try to fill memory buffer!\n");
memcpy(dcb->session->client->buffer, ptr_buffer, n);
dcb->session->client->buffer_ptr = dcb->session->client->buffer;
fprintf(stderr, "<<<< Buffer Write to client has %i bytes\n", dcb->session->client->buff_bytes);
if (n > 1) {
fprintf(stderr, "<<<< Buffer bytes last 2 [%i]\n", ptr_buffer[0]);
fprintf(stderr, "<<<< Buffer bytes last [%i]\n", ptr_buffer[1]);
}
} else {
fprintf(stderr, "<<< do data in memory for Buffer Write to client\n");
}
return 0;
}
} else {
n = n - w;
ptr_buffer = ptr_buffer + w;
fprintf(stderr, "<<< Write: pointer to buffer %i bytes shifted\n", w);
memset(&dcb->session->client->buff_bytes, '\0', sizeof(int));
}
}
return 1; return 1;
} }
#ifdef GW_DEBUG_READ_EVENT #ifdef GW_DEBUG_READ_EVENT
@ -168,6 +109,75 @@ int gw_read_backend_event(DCB *dcb, int epfd) {
return 1; return 1;
} }
/*
* Write function for client DCB
*
* @param dcb The DCB of the client
* @param queue Queue of buffers to write
*/
int
MySQLWrite(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);
}
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;
}
spinlock_release(&dcb->writeqlock);
if (queue && (saved_errno != EAGAIN || saved_errno != EWOULDBLOCK))
{
/* We had a real write failure that we must deal with */
return 0;
}
return 1;
}
////////////////////////////////////////// //////////////////////////////////////////
//backend write event triggered by EPOLLOUT //backend write event triggered by EPOLLOUT
////////////////////////////////////////// //////////////////////////////////////////
@ -322,7 +332,6 @@ int gw_handle_write_event(DCB *dcb, int epfd) {
MySQLProtocol *protocol = NULL; MySQLProtocol *protocol = NULL;
int n; int n;
struct epoll_event new_event; struct epoll_event new_event;
n = dcb->buff_bytes;
if (dcb == NULL) { if (dcb == NULL) {
@ -360,8 +369,7 @@ int gw_handle_write_event(DCB *dcb, int epfd) {
} }
if (dcb->session->backends) { if (dcb->session->backends) {
fprintf(stderr, "CLIENT WRITE READY State [%i], FIRST bytes left to write %i from back %i to client %i\n", dcb->state, dcb->buff_bytes, dcb->session->backends->fd, dcb->fd); fprintf(stderr, "CLIENT WRITE READY State [%i], FIRST bytes left to write %i from back %i to client %i\n", dcb->state, gwbuf_length(dcb->writeq), dcb->session->backends->fd, dcb->fd);
fprintf(stderr, "CLIENT WRITE READY, SECOND bytes left to write %i from back %i to client %i\n", dcb->second_buff_bytes, dcb->session->backends->fd, dcb->fd);
} }
//#ifdef GW_DEBUG_WRITE_EVENT //#ifdef GW_DEBUG_WRITE_EVENT
@ -392,50 +400,40 @@ int gw_handle_write_event(DCB *dcb, int epfd) {
if ((protocol->state == MYSQL_IDLE) || (protocol->state == MYSQL_WAITING_RESULT)) { if ((protocol->state == MYSQL_IDLE) || (protocol->state == MYSQL_WAITING_RESULT)) {
int w; int w;
int m; int m;
int saved_errno = 0;
if (dcb->buff_bytes > 0) { spinlock_acquire(&dcb->writeqlock);
fprintf(stderr, "<<< Writing unsent data for state [%i], bytes %i\n", protocol->state, dcb->buff_bytes); if (dcb->writeq)
{
int len;
if (dcb->buff_bytes > 2) /*
fprintf(stderr, "READ BUFFER last 2 byte [%i%i]\n", dcb->buffer[dcb->buff_bytes-2], dcb->buffer[dcb->buff_bytes-1]); * Loop over the buffer chain in the pendign writeq
* Send as much of the data in that chain as possible and
* leave any balance on the write queue.
*/
while (dcb->writeq != NULL)
{
len = GWBUF_LENGTH(dcb->writeq);
GW_NOINTR_CALL(w = write(dcb->fd, GWBUF_DATA(dcb->writeq), len););
saved_errno = errno;
if (w < 0)
{
break;
}
w = write(dcb->fd, dcb->buffer_ptr, dcb->buff_bytes); /*
* Pull the number of bytes we have written from
if (w < 0) { * queue with have.
if ((w != EAGAIN) || (w!= EWOULDBLOCK)) { */
return 1; dcb->writeq = gwbuf_consume(dcb->writeq, w);
} else if (w < len)
return 0; {
/* We didn't write all the data */
}
} }
fprintf(stderr, "<<<<< Written %i bytes, left %i\n", w, dcb->buff_bytes - w);
n = n-w;
memcpy(&dcb->buff_bytes, &n, sizeof(int));
dcb->buffer_ptr = dcb->buffer_ptr + w;
fprintf(stderr, "<<<<< Next time write %i bytes, buffer_ptr is %i bytes shifted\n", n, w);
} else {
fprintf(stderr, "<<<< Nothing to do with FIRST buffer left bytes\n");
} }
m = dcb->second_buff_bytes; spinlock_release(&dcb->writeqlock);
if (dcb->second_buff_bytes) {
fprintf(stderr, "<<<< Now use the SECOND buffer left %i bytes\n", m);
w = write(dcb->fd, dcb->second_buffer_ptr, dcb->second_buff_bytes);
if (w < 0) {
if ((w != EAGAIN) || (w!= EWOULDBLOCK)) {
return 1;
} else
return 0;
}
fprintf(stderr, "<<<<< second Written %i bytes, left %i\n", w, dcb->second_buff_bytes - w);
m = m-w;
memcpy(&dcb->second_buff_bytes, &m, sizeof(int));
dcb->second_buffer_ptr = dcb->second_buffer_ptr + w;
}
fprintf(stderr, "<<<< Nothing to do with SECOND buffer left bytes\n");
return 1; return 1;
} }
@ -541,7 +539,6 @@ void MySQLListener(int epfd, char *config_bind) {
int MySQLAccept(DCB *listener, int efd) { int MySQLAccept(DCB *listener, int efd) {
int accept_counter = 0;
fprintf(stderr, "MySQL Listener socket is: %i\n", listener->fd); fprintf(stderr, "MySQL Listener socket is: %i\n", listener->fd);
@ -574,9 +571,9 @@ int MySQLAccept(DCB *listener, int efd) {
} }
} }
accept_counter++; listener->stats.n_accepts++;
fprintf(stderr, "Processing %i connection fd %i for listener %i\n", accept_counter, c_sock, listener->fd); fprintf(stderr, "Processing %i connection fd %i for listener %i\n", listener->stats.n_accepts, c_sock, listener->fd);
// set nonblocking // set nonblocking
setsockopt(c_sock, SOL_SOCKET, SO_SNDBUF, &sendbuf, optlen); setsockopt(c_sock, SOL_SOCKET, SO_SNDBUF, &sendbuf, optlen);
@ -629,7 +626,7 @@ int MySQLAccept(DCB *listener, int efd) {
backend->state = DCB_STATE_POLLING; backend->state = DCB_STATE_POLLING;
backend->session = session; backend->session = session;
(backend->func).read = gw_read_backend_event; (backend->func).read = gw_read_backend_event;
(backend->func).write = gw_write_backend_event; (backend->func).write_ready = gw_write_backend_event;
(backend->func).error = handle_event_errors_backend; (backend->func).error = handle_event_errors_backend;
// assume here one backend only. // assume here one backend only.
@ -643,7 +640,8 @@ int MySQLAccept(DCB *listener, int efd) {
// assign function poiters to "func" field // assign function poiters to "func" field
(client->func).error = handle_event_errors; (client->func).error = handle_event_errors;
(client->func).read = gw_route_read_event; (client->func).read = gw_route_read_event;
(client->func).write = gw_handle_write_event; (client->func).write = MySQLWrite;
(client->func).write_ready = gw_handle_write_event;
// edge triggering flag added // edge triggering flag added
ee.events = EPOLLIN | EPOLLOUT | EPOLLET; ee.events = EPOLLIN | EPOLLOUT | EPOLLET;
@ -708,7 +706,7 @@ static char gw_randomchar() {
int gw_generate_random_str(char *output, int len) { int gw_generate_random_str(char *output, int len) {
int i; int i;
srand(time()); srand(time(0L));
for ( i = 0; i < len; ++i ) { for ( i = 0; i < len; ++i ) {
output[i] = gw_randomchar(); output[i] = gw_randomchar();

36
include/dcb.h
View File

@ -17,6 +17,8 @@
* *
* Copyright SkySQL Ab 2013 * Copyright SkySQL Ab 2013
*/ */
#include <spinlock.h>
#include <buffer.h>
struct session; struct session;
@ -32,7 +34,6 @@ struct session;
* entry points * entry points
* *
*/ */
*/
struct dcb; struct dcb;
@ -50,14 +51,19 @@ typedef struct gw_protocol {
* close Gateway close entry point for the socket * close Gateway close entry point for the socket
*/ */
int (*read)(struct dcb *, int); int (*read)(struct dcb *, int);
int (*write)(struct dcb *, int); int (*write)(struct dcb *, GWBUF *);
int (*write_ready)(struct dcb *); int (*write_ready)(struct dcb *, int);
int (*error)(struct dcb *, int); int (*error)(struct dcb *, int);
int (*hangup)(struct dcb *, int); int (*hangup)(struct dcb *, int);
int (*accept)(struct dcb *, int); int (*accept)(struct dcb *, int);
int (*close)(struct dcb *, int); int (*close)(struct dcb *, int);
} GWPROTOCOL; } GWPROTOCOL;
typedef struct dcbstats {
int n_reads; /* Number of reads on this descriptor */
int n_writes; /* Number of writes on this descriptor */
int n_accepts; /* Number of accepts on this descriptor */
} DCBSTATS;
/* /*
* Descriptor Control Block * Descriptor Control Block
*/ */
@ -68,16 +74,12 @@ typedef struct dcb {
struct session *session; /* The owning session */ struct session *session; /* The owning session */
GWPROTOCOL func; /* The functions for this descrioptor */ GWPROTOCOL func; /* The functions for this descrioptor */
/* queue buffer for write SPINLOCK writeqlock; /* Write Queue spinlock */
is now a two buffer implementation GWBUF *writeq; /* Write Data Queue */
Only used in client write
*/ DCBSTATS stats; /* DCB related statistics */
uint8_t buffer[MAX_BUFFER_SIZE]; /* network buffer */
int buff_bytes; /* bytes in buffer */ struct dcb *next; /* Next DCB in the chain of allocated DCB's */
uint8_t *buffer_ptr; /* buffer pointer */
uint8_t second_buffer[MAX_BUFFER_SIZE]; /* 2nd network buffer */
int second_buff_bytes; /* 2nd bytes in buffer */
uint8_t *second_buffer_ptr; /* 2nd buffer pointer */
} DCB; } DCB;
/* DCB states */ /* DCB states */
@ -87,10 +89,16 @@ typedef struct dcb {
#define DCB_STATE_PROCESSING 4 /* Processing an event */ #define DCB_STATE_PROCESSING 4 /* Processing an event */
#define DCB_STATE_LISTENING 5 /* The DCB is for a listening socket */ #define DCB_STATE_LISTENING 5 /* The DCB is for a listening socket */
#define DCB_STATE_DISCONNECTED 6 /* The socket is now closed */ #define DCB_STATE_DISCONNECTED 6 /* The socket is now closed */
#define DCB_STATE_FREED 7 /* Memory freed */ #define DCB_STATE_FREED 7 /* Memory freed */
/* A few useful macros */ /* A few useful macros */
#define DCB_SESSION(x) (x)->session #define DCB_SESSION(x) (x)->session
#define DCB_PROTOCOL(x, type) (type *)((x)->protocol) #define DCB_PROTOCOL(x, type) (type *)((x)->protocol)
extern DCB *alloc_dcb(); /* Allocate a DCB */
extern void free_dcb(DCB *); /* Free a DCB */
extern void printAllDCBs(); /* Debug to print all DCB in the system */
extern void printDCB(DCB *); /* Debug print routine */
extern const char *gw_dcb_state2string(int); /* DCB state to string */
#endif #endif