/* Copyright (C) 2000 MySQL AB & MySQL Finland AB & TCX DataKonsult AB
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Library General Public
License as published by the Free Software Foundation; either
version 2 of the License, or (at your option) any later version.
This library 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
Library General Public License for more details.
You should have received a copy of the GNU Library General Public
License along with this library; if not, write to the Free
Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
MA 02111-1301, USA */
/* Write and read of logical packets to/from socket
** Writes are cached into net_buffer_length big packets.
** Read packets are reallocated dynamicly when reading big packets.
** Each logical packet has the following pre-info:
** 3 byte length & 1 byte package-number.
*/
#include <my_global.h>
#include <violite.h>
#include <my_sys.h>
#include <m_string.h>
#include "mysql.h"
#include "mysqld_error.h"
#include <signal.h>
#include <errno.h>
#include <sys/types.h>
#ifndef _WIN32
#include <poll.h>
#endif
#define MAX_PACKET_LENGTH (256L*256L*256L-1)
/* net_buffer_length and max_allowed_packet are defined in mysql.h
See bug conc-57
*/
#undef net_buffer_length
#undef max_allowed_packet
ulong max_allowed_packet=1024L * 1024L * 1024L;
ulong net_read_timeout= NET_READ_TIMEOUT;
ulong net_write_timeout= NET_WRITE_TIMEOUT;
ulong net_buffer_length=8192; /* Default length. Enlarged if necessary */
#if !defined(_WIN32) && !defined(MSDOS)
#include <sys/socket.h>
#else
#undef MYSQL_SERVER /* Win32 can't handle interrupts */
#endif
#if !defined(MSDOS) && !defined(_WIN32) && !defined(HAVE_BROKEN_NETINET_INCLUDES) && !defined(__BEOS__)
#include <netinet/in_systm.h>
#include <netinet/in.h>
#include <netinet/ip.h>
#if !defined(alpha_linux_port)
#include <netinet/tcp.h>
#endif
#endif
#include "mysqld_error.h"
#ifdef MYSQL_SERVER
#include "my_pthread.h"
#include "thr_alarm.h"
void sql_print_error(const char *format,...);
#define RETRY_COUNT mysqld_net_retry_count
extern ulong mysqld_net_retry_count;
#else
#ifdef OS2 /* avoid name conflict */
#define thr_alarm_t thr_alarm_t_net
#define ALARM ALARM_net
#endif
typedef my_bool thr_alarm_t;
typedef my_bool ALARM;
#define thr_alarm_init(A) (*(A))=0
#define thr_alarm_in_use(A) (*(A))
#define thr_end_alarm(A)
#define thr_alarm(A,B,C) local_thr_alarm((A),(B),(C))
static inline int local_thr_alarm(my_bool *A,int B __attribute__((unused)),ALARM *C __attribute__((unused)))
{
*A=1;
return 0;
}
#define thr_got_alarm(A) 0
#define RETRY_COUNT 1
#endif
#ifdef MYSQL_SERVER
extern ulong bytes_sent, bytes_received;
extern pthread_mutex_t LOCK_bytes_sent , LOCK_bytes_received;
#else
#undef statistic_add
#define statistic_add(A,B,C)
#endif
/*
** Give error if a too big packet is found
** The server can change this with the -O switch, but because the client
** can't normally do this the client should have a bigger max-buffer.
*/
#define TEST_BLOCKING 8
static int net_write_buff(NET *net,const char *packet, size_t len);
/* Init with packet info */
int my_net_init(NET *net, Vio* vio)
{
if (!(net->buff=(uchar*) my_malloc(net_buffer_length,MYF(MY_WME | MY_ZEROFILL))))
return 1;
max_allowed_packet= net->max_packet_size= MAX(net_buffer_length, max_allowed_packet);
net->buff_end=net->buff+(net->max_packet=net_buffer_length);
net->vio = vio;
net->error=0; net->return_status=0;
net->read_timeout=(uint) net_read_timeout; /* Timeout for read */
net->compress_pkt_nr= net->pkt_nr= 0;
net->write_pos=net->read_pos = net->buff;
net->last_error[0]= net->sqlstate[0] =0;
net->compress=0; net->reading_or_writing=0;
net->where_b = net->remain_in_buf=0;
net->last_errno=0;
if (vio != 0) /* If real connection */
{
net->fd = vio_fd(vio); /* For perl DBI/DBD */
#if defined(MYSQL_SERVER) && !defined(__WIN32) && !defined(__EMX__) && !defined(OS2)
if (!(test_flags & TEST_BLOCKING))
vio_blocking(vio, FALSE, 0);
#endif
vio_fastsend(vio);
}
return 0;
}
void net_end(NET *net)
{
my_free(net->buff);
net->buff=0;
}
/* Realloc the packet buffer */
static my_bool net_realloc(NET *net, size_t length)
{
uchar *buff;
size_t pkt_length;
DBUG_ENTER("net_realloc");
DBUG_PRINT("info", ("length: %lu max_allowed_packet: %lu",
(ulong)length, max_allowed_packet));
if (length >= net->max_packet_size)
{
DBUG_PRINT("error",("Packet too large (%lu)", length));
net->error=1;
net->last_errno=ER_NET_PACKET_TOO_LARGE;
DBUG_RETURN(1);
}
pkt_length = (length+IO_SIZE-1) & ~(IO_SIZE-1);
/* reallocate buffer:
size= pkt_length + NET_HEADER_SIZE + COMP_HEADER_SIZE */
if (!(buff=(uchar*) my_realloc((char*) net->buff,
pkt_length + NET_HEADER_SIZE + COMP_HEADER_SIZE,
MYF(MY_WME))))
{
DBUG_PRINT("info", ("Out of memory"));
net->error=1;
DBUG_RETURN(1);
}
net->buff=net->write_pos=buff;
net->buff_end=buff+(net->max_packet=pkt_length);
DBUG_RETURN(0);
}
/* check if the socket is still alive */
static my_bool net_check_socket_status(my_socket sock)
{
#ifndef _WIN32
struct pollfd poll_fd;
#else
FD_SET sfds;
struct timeval tv= {0,0};
#endif
int res;
#ifndef _WIN32
memset(&poll_fd, 0, sizeof(struct pollfd));
poll_fd.events= POLLPRI | POLLIN;
poll_fd.fd= sock;
res= poll(&poll_fd, 1, 0);
if (res <= 0) /* timeout or error */
return FALSE;
if (!(poll_fd.revents & (POLLIN | POLLPRI)))
return FALSE;
return TRUE;
#else
/* We can't use the WSAPoll function, it's broken :-(
(see Windows 8 Bugs 309411 - WSAPoll does not report failed connections)
Instead we need to use select function:
If TIMEVAL is initialized to {0, 0}, select will return immediately;
this is used to poll the state of the selected sockets.
*/
FD_ZERO(&sfds);
FD_SET(sock, &sfds);
res= select(sock + 1, &sfds, NULL, NULL, &tv);
if (res > 0 && FD_ISSET(sock, &sfds))
return TRUE;
return FALSE;
#endif
}
/* Remove unwanted characters from connection */
void net_clear(NET *net)
{
DBUG_ENTER("net_clear");
/* see conc-71: we need to check the socket status first:
if the socket is dead we set net->error, so net_flush
will report an error */
while (net_check_socket_status(net->vio->sd))
{
/* vio_read returns size_t. so casting to long is required to check for -1 */
if ((long)vio_read(net->vio, (gptr)net->buff, (size_t) net->max_packet) <= 0)
{
net->error= 2;
DBUG_PRINT("info", ("socket disconnected"));
DBUG_VOID_RETURN;
}
}
net->compress_pkt_nr= net->pkt_nr=0; /* Ready for new command */
net->write_pos=net->buff;
DBUG_VOID_RETURN;
}
/* Flush write_buffer if not empty. */
int net_flush(NET *net)
{
int error=0;
DBUG_ENTER("net_flush");
if (net->buff != net->write_pos)
{
error=net_real_write(net,(char*) net->buff,
(size_t) (net->write_pos - net->buff));
net->write_pos=net->buff;
}
if (net->compress)
net->pkt_nr= net->compress_pkt_nr;
DBUG_RETURN(error);
}
/*****************************************************************************
** Write something to server/client buffer
*****************************************************************************/
/*
** Write a logical packet with packet header
** Format: Packet length (3 bytes), packet number(1 byte)
** When compression is used a 3 byte compression length is added
** NOTE: If compression is used the original package is destroyed!
*/
int
my_net_write(NET *net, const char *packet, size_t len)
{
uchar buff[NET_HEADER_SIZE];
while (len >= MAX_PACKET_LENGTH)
{
const ulong max_len= MAX_PACKET_LENGTH;
int3store(buff,max_len);
buff[3]= (uchar)net->pkt_nr++;
if (net_write_buff(net,(char*) buff,NET_HEADER_SIZE) ||
net_write_buff(net, packet, max_len))
return 1;
packet+= max_len;
len-= max_len;
}
/* write last remaining packet, size can be zero */
int3store(buff, len);
buff[3]= (uchar)net->pkt_nr++;
if (net_write_buff(net,(char*) buff,NET_HEADER_SIZE) ||
net_write_buff(net, packet, len))
return 1;
return 0;
}
int
net_write_command(NET *net, uchar command,
const char *packet, size_t len)
{
uchar buff[NET_HEADER_SIZE+1];
size_t buff_size= NET_HEADER_SIZE + 1;
size_t length= 1 + len; /* 1 extra byte for command */
int rc;
buff[NET_HEADER_SIZE]= 0;
buff[4]=command;
if (length >= MAX_PACKET_LENGTH)
{
len= MAX_PACKET_LENGTH - 1;
do
{
int3store(buff, MAX_PACKET_LENGTH);
buff[3]= (net->compress) ? 0 : (uchar) (net->pkt_nr++);
if (net_write_buff(net, (char *)buff, buff_size) ||
net_write_buff(net, packet, len))
return(1);
packet+= len;
length-= MAX_PACKET_LENGTH;
len= MAX_PACKET_LENGTH;
buff_size= NET_HEADER_SIZE; /* don't send command for further packets */
} while (length >= MAX_PACKET_LENGTH);
len= length;
}
int3store(buff,length);
buff[3]= (net->compress) ? 0 : (uchar) (net->pkt_nr++);
rc= test (net_write_buff(net,(char *)buff, buff_size) ||
net_write_buff(net,packet,len) ||
net_flush(net));
return rc;
}
static int
net_write_buff(NET *net,const char *packet, size_t len)
{
size_t left_length;
if (net->max_packet > MAX_PACKET_LENGTH &&
net->compress)
left_length= (size_t)(MAX_PACKET_LENGTH - (net->write_pos - net->buff));
else
left_length=(size_t) (net->buff_end - net->write_pos);
if (len > left_length)
{
if (net->write_pos != net->buff)
{
memcpy((char*) net->write_pos,packet,left_length);
if (net_real_write(net,(char*) net->buff,
(size_t)(net->write_pos - net->buff) + left_length))
return 1;
packet+=left_length;
len-=left_length;
net->write_pos= net->buff;
}
if (net->compress)
{
/* uncompressed length is stored in 3 bytes,so
packet can't be > 0xFFFFFF */
left_length= MAX_PACKET_LENGTH;
while (len > left_length)
{
if (net_real_write(net, packet, left_length))
return 1;
packet+= left_length;
len-= left_length;
}
}
if (len > net->max_packet)
return(test(net_real_write(net, packet, len)));
}
memcpy((char*) net->write_pos,packet,len);
net->write_pos+=len;
return 0;
}
/* Read and write using timeouts */
int
net_real_write(NET *net,const char *packet,size_t len)
{
size_t length;
char *pos,*end;
thr_alarm_t alarmed;
#if !defined(_WIN32) && !defined(__EMX__) && !defined(OS2)
ALARM alarm_buff;
#endif
uint retry_count=0;
my_bool net_blocking = vio_is_blocking(net->vio);
DBUG_ENTER("net_real_write");
if (net->error == 2)
DBUG_RETURN(-1); /* socket can't be used */
net->reading_or_writing=2;
#ifdef HAVE_COMPRESS
if (net->compress)
{
size_t complen;
uchar *b;
uint header_length=NET_HEADER_SIZE+COMP_HEADER_SIZE;
if (!(b=(uchar*) my_malloc(len + NET_HEADER_SIZE + COMP_HEADER_SIZE + 1,
MYF(MY_WME))))
{
net->last_errno=ER_OUT_OF_RESOURCES;
net->error=2;
net->reading_or_writing=0;
DBUG_RETURN(1);
}
memcpy(b+header_length,packet,len);
if (my_compress((unsigned char*) b+header_length,&len,&complen))
{
DBUG_PRINT("warning",
("Compression error; Continuing without compression"));
complen=0;
}
int3store(&b[NET_HEADER_SIZE],complen);
int3store(b,len);
b[3]=(uchar) (net->compress_pkt_nr++);
len+= header_length;
packet= (char*) b;
}
#endif /* HAVE_COMPRESS */
alarmed=0;
pos=(char*) packet; end=pos+len;
while (pos != end)
{
if ((long) (length=vio_write(net->vio,pos,(size_t) (end-pos))) <= 0)
{
my_bool interrupted = vio_should_retry(net->vio);
#if (!defined(_WIN32) && !defined(__EMX__) && !defined(OS2))
if ((interrupted || length==0) && !thr_alarm_in_use(&alarmed))
{
if (!thr_alarm(&alarmed,(uint) net_write_timeout,&alarm_buff))
{ /* Always true for client */
if (!vio_is_blocking(net->vio))
{
while (vio_blocking(net->vio, TRUE, 0) < 0)
{
if (vio_should_retry(net->vio) && retry_count++ < RETRY_COUNT)
continue;
#ifdef EXTRA_DEBUG
fprintf(stderr,
"%s: my_net_write: fcntl returned error %d, aborting thread\n",
my_progname,vio_errno(net->vio));
#endif /* EXTRA_DEBUG */
net->error=2; /* Close socket */
net->last_errno= (interrupted ?
ER_NET_WRITE_INTERRUPTED : ER_NET_ERROR_ON_WRITE);
goto end;
}
}
retry_count=0;
continue;
}
}
else
#endif /* (!defined(_WIN32) && !defined(__EMX__)) */
if (thr_alarm_in_use(&alarmed) && !thr_got_alarm(&alarmed) &&
interrupted)
{
if (retry_count++ < RETRY_COUNT)
continue;
#ifdef EXTRA_DEBUG
fprintf(stderr, "%s: write looped, aborting thread\n",
my_progname);
#endif /* EXTRA_DEBUG */
}
#if defined(THREAD_SAFE_CLIENT) && !defined(MYSQL_SERVER)
if (vio_errno(net->vio) == SOCKET_EINTR)
{
DBUG_PRINT("warning",("Interrupted write. Retrying..."));
continue;
}
#endif /* defined(THREAD_SAFE_CLIENT) && !defined(MYSQL_SERVER) */
net->error=2; /* Close socket */
net->last_errno= (interrupted ? ER_NET_WRITE_INTERRUPTED :
ER_NET_ERROR_ON_WRITE);
break;
}
pos+=length;
statistic_add(bytes_sent,length,&LOCK_bytes_sent);
}
#ifndef _WIN32
end:
#endif
#ifdef HAVE_COMPRESS
if (net->compress)
my_free((void *)packet);
#endif
if (thr_alarm_in_use(&alarmed))
{
thr_end_alarm(&alarmed);
vio_blocking(net->vio, net_blocking, 0);
}
net->reading_or_writing=0;
DBUG_RETURN(((int) (pos != end)));
}
/*****************************************************************************
** Read something from server/clinet
*****************************************************************************/
#ifdef MYSQL_SERVER
/*
Help function to clear the commuication buffer when we get a too
big packet
*/
static void my_net_skip_rest(NET *net, ulong remain, thr_alarm_t *alarmed,
ALARM *alarm_buff)
{
uint retry_count=0;
if (!thr_alarm_in_use(alarmed))
{
if (thr_alarm(alarmed,net->timeout,alarm_buff) ||
(!vio_is_blocking(net->vio) && vio_blocking(net->vio,TRUE, 0) < 0))
return; /* Can't setup, abort */
}
while (remain > 0)
{
ulong length;
if ((int) (length=vio_read(net->vio,(char*) net->buff,remain)) <= 0L)
{
my_bool interrupted = vio_should_retry(net->vio);
if (!thr_got_alarm(alarmed) && interrupted)
{ /* Probably in MIT threads */
if (retry_count++ < RETRY_COUNT)
continue;
}
return;
}
remain -=(ulong) length;
statistic_add(bytes_received,(ulong) length,&LOCK_bytes_received);
}
}
#endif /* MYSQL_SERVER */
static ulong
my_real_read(NET *net, size_t *complen)
{
uchar *pos;
size_t length;
uint i,retry_count=0;
ulong len=packet_error;
thr_alarm_t alarmed;
#if (!defined(_WIN32) && !defined(__EMX__) && !defined(OS2)) || defined(MYSQL_SERVER)
ALARM alarm_buff;
#endif
my_bool net_blocking=vio_is_blocking(net->vio);
size_t remain= (net->compress ? NET_HEADER_SIZE+COMP_HEADER_SIZE :
NET_HEADER_SIZE);
*complen = 0;
net->reading_or_writing=1;
thr_alarm_init(&alarmed);
#ifdef MYSQL_SERVER
if (net_blocking)
thr_alarm(&alarmed,net->timeout,&alarm_buff);
#endif /* MYSQL_SERVER */
pos = net->buff + net->where_b; /* net->packet -4 */
for (i=0 ; i < 2 ; i++)
{
while (remain > 0)
{
/* First read is done with non blocking mode */
if ((long) (length=vio_read(net->vio,(char*) pos,remain)) <= 0L)
{
my_bool interrupted = vio_should_retry(net->vio);
DBUG_PRINT("info",("vio_read returned %d, errno: %d",
length, vio_errno(net->vio)));
#if (!defined(_WIN32) && !defined(__EMX__) && !defined(OS2)) || defined(MYSQL_SERVER)
/*
We got an error that there was no data on the socket. We now set up
an alarm to not 'read forever', change the socket to non blocking
mode and try again
*/
if ((interrupted || length == 0) && !thr_alarm_in_use(&alarmed))
{
if (!thr_alarm(&alarmed,net->read_timeout,&alarm_buff)) /* Don't wait too long */
{
if (!vio_is_blocking(net->vio))
{
while (vio_blocking(net->vio,TRUE, 0) < 0)
{
if (vio_should_retry(net->vio) &&
retry_count++ < RETRY_COUNT)
continue;
DBUG_PRINT("error",
("fcntl returned error %d, aborting thread",
vio_errno(net->vio)));
#ifdef EXTRA_DEBUG
fprintf(stderr,
"%s: read: fcntl returned error %d, aborting thread\n",
my_progname,vio_errno(net->vio));
#endif /* EXTRA_DEBUG */
len= packet_error;
net->error=2; /* Close socket */
#ifdef MYSQL_SERVER
net->last_errno=ER_NET_FCNTL_ERROR;
#endif
goto end;
}
}
retry_count=0;
continue;
}
}
#endif /* (!defined(_WIN32) && !defined(__EMX__)) || defined(MYSQL_SERVER) */
if (thr_alarm_in_use(&alarmed) && !thr_got_alarm(&alarmed) &&
interrupted)
{ /* Probably in MIT threads */
if (retry_count++ < RETRY_COUNT)
continue;
#ifdef EXTRA_DEBUG
fprintf(stderr, "%s: read looped with error %d, aborting thread\n",
my_progname,vio_errno(net->vio));
#endif /* EXTRA_DEBUG */
}
#if defined(THREAD_SAFE_CLIENT) && !defined(MYSQL_SERVER)
if (vio_should_retry(net->vio))
{
DBUG_PRINT("warning",("Interrupted read. Retrying..."));
continue;
}
#endif
DBUG_PRINT("error",("Couldn't read packet: remain: %d errno: %d length: %d alarmed: %d", remain,vio_errno(net->vio),length,alarmed));
len= packet_error;
net->error=2; /* Close socket */
goto end;
}
remain -= (ulong) length;
pos+= (ulong) length;
statistic_add(bytes_received,(ulong) length,&LOCK_bytes_received);
}
if (i == 0)
{ /* First parts is packet length */
ulong helping;
if (net->buff[net->where_b + 3] != (uchar) net->pkt_nr)
{
if (net->buff[net->where_b] != (uchar) 255)
{
DBUG_PRINT("error",
("Packets out of order (Found: %d, expected %d)",
(int) net->buff[net->where_b + 3],
(uint) (uchar) net->pkt_nr));
#ifdef EXTRA_DEBUG
fprintf(stderr,"Packets out of order (Found: %d, expected %d)\n",
(int) net->buff[net->where_b + 3],
(uint) (uchar) net->pkt_nr);
#endif
}
len= packet_error;
#ifdef MYSQL_SERVER
net->last_errno=ER_NET_PACKETS_OUT_OF_ORDER;
#endif
goto end;
}
net->compress_pkt_nr= ++net->pkt_nr;
#ifdef HAVE_COMPRESS
if (net->compress)
{
/* complen is > 0 if package is really compressed */
*complen=uint3korr(&(net->buff[net->where_b + NET_HEADER_SIZE]));
}
#endif
len=uint3korr(net->buff+net->where_b);
if (!len)
goto end;
helping = max(len,(ulong)*complen) + net->where_b;
/* The necessary size of net->buff */
if (helping >= net->max_packet)
{
if (net_realloc(net,helping))
{
#ifdef MYSQL_SERVER
if (i == 1)
my_net_skip_rest(net, len, &alarmed, &alarm_buff);
#endif
len= packet_error; /* Return error */
goto end;
}
}
pos=net->buff + net->where_b;
remain = len;
}
}
end:
if (thr_alarm_in_use(&alarmed))
{
thr_end_alarm(&alarmed);
vio_blocking(net->vio, net_blocking, 0);
}
net->reading_or_writing=0;
return(len);
}
ulong my_net_read(NET *net)
{
size_t len,complen;
#ifdef HAVE_COMPRESS
if (!net->compress)
{
#endif
len = my_real_read (net,(size_t *)&complen);
if (len == MAX_PACKET_LENGTH)
{
/* multi packet read */
size_t length= 0;
ulong last_pos= net->where_b;
do
{
length+= len;
net->where_b+= (unsigned long)len;
len= my_real_read(net, &complen);
} while (len == MAX_PACKET_LENGTH);
net->where_b= last_pos;
if (len != packet_error)
len+= length;
}
net->read_pos = net->buff + net->where_b;
if (len != packet_error)
net->read_pos[len]=0; /* Safeguard for mysql_use_result */
return (ulong)len;
#ifdef HAVE_COMPRESS
}
else
{
/*
compressed protocol:
--------------------------------------
packet_lengt h 3
sequence_id 1
uncompressed_length 3
--------------------------------------
compressed data packet_length - 7
--------------------------------------
Another packet will follow if:
packet_length == MAX_PACKET_LENGTH
Last package will be identified by
- packet_length is zero (special case)
- packet_length < MAX_PACKET_LENGTH
*/
size_t packet_length,
buffer_length;
size_t current= 0, start= 0;
my_bool is_multi_packet= 0;
/* check if buffer is empty */
if (!net->remain_in_buf)
{
buffer_length= 0;
}
else
{
/* save position and restore \0 character */
buffer_length= net->buf_length;
current= net->buf_length - net->remain_in_buf;
start= current;
net->buff[net->buf_length - net->remain_in_buf]=net->save_char;
}
for (;;)
{
if (buffer_length - current >= 4)
{
uchar *pos= net->buff + current;
packet_length= uint3korr(pos);
/* check if we have last package (special case: zero length) */
if (!packet_length)
{
current+= 4; /* length + sequence_id,
no more data will follow */
break;
}
if (packet_length + 4 <= buffer_length - current)
{
if (!is_multi_packet)
{
current= current + packet_length + 4;
}
else
{
/* remove packet_header */
memmove(net->buff + current,
net->buff + current + 4,
buffer_length - current);
buffer_length-= 4;
current+= packet_length;
}
/* do we have last packet ? */
if (packet_length != MAX_PACKET_LENGTH)
{
is_multi_packet= 0;
break;
}
else
is_multi_packet= 1;
if (start)
{
memmove(net->buff, net->buff + start,
buffer_length - start);
/* decrease buflen*/
buffer_length-= start;
start= 0;
}
continue;
}
}
if (start)
{
memmove(net->buff, net->buff + start, buffer_length - start);
/* decrease buflen and current */
current -= start;
buffer_length-= start;
start= 0;
}
net->where_b=buffer_length;
if ((packet_length = my_real_read(net,(size_t *)&complen)) == packet_error)
return packet_error;
if (my_uncompress((unsigned char*) net->buff + net->where_b, &packet_length, &complen))
{
len= packet_error;
net->error=2; /* caller will close socket */
net->last_errno=ER_NET_UNCOMPRESS_ERROR;
break;
return packet_error;
}
buffer_length+= complen;
}
/* set values */
net->buf_length= buffer_length;
net->remain_in_buf= buffer_length - current;
net->read_pos= net->buff + start + 4;
len= current - start - 4;
if (is_multi_packet)
len-= 4;
net->save_char= net->read_pos[len]; /* Must be saved */
net->read_pos[len]=0; /* Safeguard for mysql_use_result */
}
#endif
return (ulong)len;
}