Sweden-Number/server/request.c

213 lines
5.2 KiB
C

/*
* Server-side request handling
*
* Copyright (C) 1998 Alexandre Julliard
*/
#include "config.h"
#include <assert.h>
#include <errno.h>
#include <fcntl.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <sys/time.h>
#include <sys/types.h>
#ifdef HAVE_SYS_SOCKET_H
# include <sys/socket.h>
#endif
#include <sys/uio.h>
#include <unistd.h>
#include "winerror.h"
#include "winnt.h"
#include "winbase.h"
#include "wincon.h"
#include "thread.h"
#include "server.h"
#define WANT_REQUEST_HANDLERS
#include "request.h"
/* Some versions of glibc don't define this */
#ifndef SCM_RIGHTS
#define SCM_RIGHTS 1
#endif
struct thread *current = NULL; /* thread handling the current request */
/* socket communication static structures */
static struct iovec myiovec;
static struct msghdr msghdr = { NULL, 0, &myiovec, 1, };
#ifndef HAVE_MSGHDR_ACCRIGHTS
struct cmsg_fd
{
int len; /* sizeof structure */
int level; /* SOL_SOCKET */
int type; /* SCM_RIGHTS */
int fd; /* fd to pass */
};
static struct cmsg_fd cmsg = { sizeof(cmsg), SOL_SOCKET, SCM_RIGHTS, -1 };
#endif /* HAVE_MSGHDR_ACCRIGHTS */
/* complain about a protocol error and terminate the client connection */
void fatal_protocol_error( struct thread *thread, const char *err, ... )
{
va_list args;
va_start( args, err );
fprintf( stderr, "Protocol error:%p: ", thread );
vfprintf( stderr, err, args );
va_end( args );
kill_thread( thread, PROTOCOL_ERROR );
}
/* call a request handler */
static void call_req_handler( struct thread *thread, enum request req, int fd )
{
current = thread;
clear_error();
if (debug_level) trace_request( req, fd );
if (req < REQ_NB_REQUESTS)
{
req_handlers[req].handler( current->buffer, fd );
if (current && !current->wait) send_reply( current );
current = NULL;
return;
}
fatal_protocol_error( current, "bad request %d\n", req );
}
/* set the fd to pass to the thread */
void set_reply_fd( struct thread *thread, int pass_fd )
{
assert( thread->pass_fd == -1 );
thread->pass_fd = pass_fd;
}
/* send a reply to a thread */
void send_reply( struct thread *thread )
{
assert( !thread->wait );
if (debug_level) trace_reply( thread );
if (!write_request( thread )) set_select_events( &thread->obj, POLLOUT );
}
/* read a message from a client that has something to say */
void read_request( struct thread *thread )
{
int ret;
enum request req;
#ifdef HAVE_MSGHDR_ACCRIGHTS
msghdr.msg_accrightslen = sizeof(int);
msghdr.msg_accrights = (void *)&thread->pass_fd;
#else /* HAVE_MSGHDR_ACCRIGHTS */
msghdr.msg_control = &cmsg;
msghdr.msg_controllen = sizeof(cmsg);
cmsg.fd = -1;
#endif /* HAVE_MSGHDR_ACCRIGHTS */
assert( thread->pass_fd == -1 );
myiovec.iov_base = (void *)&req;
myiovec.iov_len = sizeof(req);
ret = recvmsg( thread->obj.fd, &msghdr, 0 );
#ifndef HAVE_MSGHDR_ACCRIGHTS
thread->pass_fd = cmsg.fd;
#endif
if (ret == sizeof(req))
{
int pass_fd = thread->pass_fd;
thread->pass_fd = -1;
call_req_handler( thread, req, pass_fd );
if (pass_fd != -1) close( pass_fd );
return;
}
if (ret == -1)
{
perror("recvmsg");
kill_thread( thread, BROKEN_PIPE );
return;
}
if (!ret) /* closed pipe */
{
kill_thread( thread, BROKEN_PIPE );
return;
}
fatal_protocol_error( thread, "partial message received %d/%d\n", ret, sizeof(req) );
}
/* send a message to a client that is ready to receive something */
int write_request( struct thread *thread )
{
int ret;
if (thread->pass_fd == -1)
{
ret = write( thread->obj.fd, &thread->error, sizeof(thread->error) );
if (ret == sizeof(thread->error)) goto ok;
}
else /* we have an fd to send */
{
#ifdef HAVE_MSGHDR_ACCRIGHTS
msghdr.msg_accrightslen = sizeof(int);
msghdr.msg_accrights = (void *)&thread->pass_fd;
#else /* HAVE_MSGHDR_ACCRIGHTS */
msghdr.msg_control = &cmsg;
msghdr.msg_controllen = sizeof(cmsg);
cmsg.fd = thread->pass_fd;
#endif /* HAVE_MSGHDR_ACCRIGHTS */
myiovec.iov_base = (void *)&thread->error;
myiovec.iov_len = sizeof(thread->error);
ret = sendmsg( thread->obj.fd, &msghdr, 0 );
close( thread->pass_fd );
thread->pass_fd = -1;
if (ret == sizeof(thread->error)) goto ok;
}
if (ret == -1)
{
if (errno == EWOULDBLOCK) return 0; /* not a fatal error */
if (errno != EPIPE) perror("sendmsg");
}
else fprintf( stderr, "Partial message sent %d/%d\n", ret, sizeof(thread->error) );
kill_thread( thread, BROKEN_PIPE );
return -1;
ok:
set_select_events( &thread->obj, POLLIN );
return 1;
}
/* set the debug level */
DECL_HANDLER(set_debug)
{
debug_level = req->level;
/* Make sure last_req is initialized */
current->last_req = REQ_SET_DEBUG;
}
/* debugger support operations */
DECL_HANDLER(debugger)
{
switch ( req->op )
{
case DEBUGGER_FREEZE_ALL:
suspend_all_threads();
break;
case DEBUGGER_UNFREEZE_ALL:
resume_all_threads();
break;
}
}