/*
* $Id$
*
* Copyright (C) 2005 iptelorg GmbH
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
/*
* tcp io wait common stuff used by tcp_main.c & tcp_read.c
* All the functions are inline because of speed reasons and because they are
* used only from 2 places.
* You also have to define:
* int handle_io(struct fd_map* fm, short events, int idx) (see below)
* (this could be trivially replaced by a callback pointer entry attached
* to the io_wait handler if more flexibility rather then performance
* is needed)
* fd_type - define to some enum of you choice and define also
* FD_TYPE_DEFINED (if you don't do it fd_type will be defined
* to int). 0 has a special not set/not init. meaning
* (a lot of sanity checks and the sigio_rt code are based on
* this assumption)
* local_malloc (defaults to pkg_malloc)
* local_free (defaults to pkg_free)
*
*/
/*
* History:
* --------
* 2005-06-13 created by andrei
* 2005-06-26 added kqueue (andrei)
* 2005-07-01 added /dev/poll (andrei)
* 2006-05-30 sigio 64 bit workarround enabled for kernels < 2.6.5 (andrei)
* 2007-11-22 when handle_io() is called in a loop check & stop if the fd was
* removed inside handle_io() (andrei)
* 2007-11-29 support for write (POLLOUT); added io_watch_chg() (andrei)
* 2008-02-04 POLLRDHUP & EPOLLRDHUP support (automatically enabled if POLLIN
* is set) (andrei)
*/
#ifndef _io_wait_h
#define _io_wait_h
#include <errno.h>
#include <string.h>
#ifdef HAVE_SIGIO_RT
#define __USE_GNU /* or else F_SETSIG won't be included */
#include <sys/types.h> /* recv */
#include <sys/socket.h> /* recv */
#include <signal.h> /* sigprocmask, sigwait a.s.o */
#endif
#define _GNU_SOURCE /* for POLLRDHUP on linux */
#include <sys/poll.h>
#include <fcntl.h>
#ifdef HAVE_EPOLL
#include <sys/epoll.h>
#endif
#ifdef HAVE_KQUEUE
#include <sys/types.h> /* needed on freebsd */
#include <sys/event.h>
#include <sys/time.h>
#endif
#ifdef HAVE_DEVPOLL
#include <sys/devpoll.h>
#endif
#ifdef HAVE_SELECT
/* needed on openbsd for select*/
#include <sys/time.h>
#include <sys/types.h>
#include <unistd.h>
/* needed according to POSIX for select*/
#include <sys/select.h>
#endif
#include "dprint.h"
#include "poll_types.h" /* poll_types*/
#ifdef HAVE_SIGIO_RT
#include "pt.h" /* mypid() */
#endif
#include "compiler_opt.h"
#ifdef HAVE_EPOLL
/* fix defines for EPOLL */
#if defined POLLRDHUP && ! defined EPOLLRDHUP
#define EPOLLRDHUP POLLRDHUP /* should work on all linuxes */
#endif /* POLLRDHUP && EPOLLRDHUP */
#endif /* HAVE_EPOLL */
extern int _os_ver; /* os version number, needed to select bugs workarrounds */
#if 0
enum fd_types; /* this should be defined from the including file,
see tcp_main.c for an example,
0 has a special meaning: not used/empty*/
#endif
#ifndef FD_TYPE_DEFINED
typedef int fd_type;
#define FD_TYPE_DEFINED
#endif
/* maps a fd to some other structure; used in almost all cases
* except epoll and maybe kqueue or /dev/poll */
struct fd_map{
int fd; /* fd no */
fd_type type; /* "data" type */
void* data; /* pointer to the corresponding structure */
short events; /* events we are interested int */
};
#ifdef HAVE_KQUEUE
#ifndef KQ_CHANGES_ARRAY_SIZE
#define KQ_CHANGES_ARRAY_SIZE 256
#ifdef __OS_netbsd
#define KEV_UDATA_CAST (intptr_t)
#else
#define KEV_UDATA_CAST
#endif
#endif
#endif
/* handler structure */
struct io_wait_handler{
enum poll_types poll_method;
int flags;
struct fd_map* fd_hash;
int fd_no; /* current index used in fd_array and the passed size for
ep_array & kq_array*/
int max_fd_no; /* maximum fd no, is also the size of fd_array,
fd_hash and ep_array*/
/* common stuff for POLL, SIGIO_RT and SELECT
* since poll support is always compiled => this will always be compiled */
struct pollfd* fd_array; /* used also by devpoll as devpoll array */
int crt_fd_array_idx; /* crt idx for which handle_io is called
(updated also by del -> internal optimization) */
/* end of common stuff */
#ifdef HAVE_EPOLL
int epfd; /* epoll ctrl fd */
struct epoll_event* ep_array;
#endif
#ifdef HAVE_SIGIO_RT
sigset_t sset; /* signal mask for sigio & sigrtmin */
int signo; /* real time signal used */
#endif
#ifdef HAVE_KQUEUE
int kq_fd;
struct kevent* kq_array; /* used for the eventlist*/
struct kevent* kq_changes; /* used for the changelist */
size_t kq_nchanges;
size_t kq_changes_size; /* size of the changes array */
#endif
#ifdef HAVE_DEVPOLL
int dpoll_fd;
#endif
#ifdef HAVE_SELECT
fd_set master_rset; /* read set */
fd_set master_wset; /* write set */
int max_fd_select; /* maximum select used fd */
#endif
};
typedef struct io_wait_handler io_wait_h;
/* get the corresponding fd_map structure pointer */
#define get_fd_map(h, fd) (&(h)->fd_hash[(fd)])
/* remove a fd_map structure from the hash; the pointer must be returned
* by get_fd_map or hash_fd_map*/
#define unhash_fd_map(pfm) \
do{ \
(pfm)->type=0 /*F_NONE */; \
(pfm)->fd=-1; \
}while(0)
/* add a fd_map structure to the fd hash */
static inline struct fd_map* hash_fd_map( io_wait_h* h,
int fd,
short events,
fd_type type,
void* data)
{
h->fd_hash[fd].fd=fd;
h->fd_hash[fd].events=events;
h->fd_hash[fd].type=type;
h->fd_hash[fd].data=data;
return &h->fd_hash[fd];
}
#ifdef HANDLE_IO_INLINE
/* generic handle io routine, this must be defined in the including file
* (faster then registering a callback pointer)
*
* params: fm - pointer to a fd hash entry
* events - combinations of POLLIN, POLLOUT, POLLERR & POLLHUP
* idx - index in the fd_array (or -1 if not known)
* return: -1 on error
* 0 on EAGAIN or when by some other way it is known that no more
* io events are queued on the fd (the receive buffer is empty).
* Usefull to detect when there are no more io events queued for
* sigio_rt, epoll_et, kqueue.
* >0 on successfull read from the fd (when there might be more io
* queued -- the receive buffer might still be non-empty)
*/
inline static int handle_io(struct fd_map* fm, short events, int idx);
#else
int handle_io(struct fd_map* fm, short events, int idx);
#endif
#ifdef HAVE_KQUEUE
/*
* kqueue specific function: register a change
* (adds a change to the kevent change array, and if full flushes it first)
*
* TODO: check if the event already exists in the change list or if it's
* complementary to an event in the list (e.g. EVFILT_WRITE, EV_DELETE
* and EVFILT_WRITE, EV_ADD for the same fd).
* returns: -1 on error, 0 on success
*/
static inline int kq_ev_change(io_wait_h* h, int fd, int filter, int flag,
void* data)
{
int n;
struct timespec tspec;
if (h->kq_nchanges>=h->kq_changes_size){
/* changes array full ! */
LOG(L_WARN, "WARNING: kq_ev_change: kqueue changes array full"
" trying to flush...\n");
tspec.tv_sec=0;
tspec.tv_nsec=0;
again:
n=kevent(h->kq_fd, h->kq_changes, h->kq_nchanges, 0, 0, &tspec);
if (n==-1){
if (errno==EINTR) goto again;
LOG(L_ERR, "ERROR: io_watch_add: kevent flush changes "
" failed: %s [%d]\n", strerror(errno), errno);
return -1;
}
h->kq_nchanges=0; /* changes array is empty */
}
EV_SET(&h->kq_changes[h->kq_nchanges], fd, filter, flag, 0, 0,
KEV_UDATA_CAST data);
h->kq_nchanges++;
return 0;
}
#endif
/* generic io_watch_add function
* Params:
* h - pointer to initialized io_wait handle
* fd - fd to watch
* events - bitmap with the fd events for which the fd should be watched
* (combination of POLLIN and POLLOUT)
* type - fd type (non 0 value, returned in the call to handle_io)
* data - pointer/private data returned in the handle_io call
* returns 0 on success, -1 on error
*
* WARNING: handle_io() can be called immediately (from io_watch_add()) so
* make sure that any dependent init. (e.g. data stuff) is made before
* calling io_watch_add
*
* this version should be faster than pointers to poll_method specific
* functions (it avoids functions calls, the overhead being only an extra
* switch())*/
inline static int io_watch_add( io_wait_h* h,
int fd,
short events,
fd_type type,
void* data)
{
/* helper macros */
#define fd_array_setup(ev) \
do{ \
h->fd_array[h->fd_no].fd=fd; \
h->fd_array[h->fd_no].events=(ev); /* useless for select */ \
h->fd_array[h->fd_no].revents=0; /* useless for select */ \
}while(0)
#define set_fd_flags(f) \
do{ \
flags=fcntl(fd, F_GETFL); \
if (flags==-1){ \
LOG(L_ERR, "ERROR: io_watch_add: fnctl: GETFL failed:" \
" %s [%d]\n", strerror(errno), errno); \
goto error; \
} \
if (fcntl(fd, F_SETFL, flags|(f))==-1){ \
LOG(L_ERR, "ERROR: io_watch_add: fnctl: SETFL" \
" failed: %s [%d]\n", strerror(errno), errno); \
goto error; \
} \
}while(0)
struct fd_map* e;
int flags;
#ifdef HAVE_EPOLL
struct epoll_event ep_event;
#endif
#ifdef HAVE_DEVPOLL
struct pollfd pfd;
#endif
#if defined(HAVE_SIGIO_RT) || defined (HAVE_EPOLL)
int n;
#endif
#if defined(HAVE_SIGIO_RT)
int idx;
int check_io;
struct pollfd pf;
check_io=0; /* set to 1 if we need to check for pre-existing queued
io/data on the fd */
idx=-1;
#endif
e=0;
/* sanity checks */
if (unlikely(fd==-1)){
LOG(L_CRIT, "BUG: io_watch_add: fd is -1!\n");
goto error;
}
if (unlikely((events&(POLLIN|POLLOUT))==0)){
LOG(L_CRIT, "BUG: io_watch_add: invalid events: 0x%0x\n", events);
goto error;
}
/* check if not too big */
if (unlikely(h->fd_no>=h->max_fd_no)){
LOG(L_CRIT, "ERROR: io_watch_add: maximum fd number exceeded:"
" %d/%d\n", h->fd_no, h->max_fd_no);
goto error;
}
DBG("DBG: io_watch_add(%p, %d, %d, %p), fd_no=%d\n",
h, fd, type, data, h->fd_no);
/* hash sanity check */
e=get_fd_map(h, fd);
if (unlikely(e && (e->type!=0 /*F_NONE*/))){
LOG(L_ERR, "ERROR: io_watch_add: trying to overwrite entry %d"
" watched for %x in the hash(%d, %d, %p) with (%d, %d, %p)\n",
fd, events, e->fd, e->type, e->data, fd, type, data);
e=0;
goto error;
}
if (unlikely((e=hash_fd_map(h, fd, events, type, data))==0)){
LOG(L_ERR, "ERROR: io_watch_add: failed to hash the fd %d\n", fd);
goto error;
}
switch(h->poll_method){ /* faster then pointer to functions */
case POLL_POLL:
#ifdef POLLRDHUP
/* listen to POLLRDHUP by default (if POLLIN) */
events|=((int)!(events & POLLIN) - 1) & POLLRDHUP;
#endif /* POLLRDHUP */
fd_array_setup(events);
set_fd_flags(O_NONBLOCK);
break;
#ifdef HAVE_SELECT
case POLL_SELECT:
fd_array_setup(events);
if (likely(events & POLLIN))
FD_SET(fd, &h->master_rset);
if (unlikely(events & POLLOUT))
FD_SET(fd, &h->master_wset);
if (h->max_fd_select<fd) h->max_fd_select=fd;
break;
#endif
#ifdef HAVE_SIGIO_RT
case POLL_SIGIO_RT:
fd_array_setup(events);
/* re-set O_ASYNC might be needed, if not done from
* io_watch_del (or if somebody wants to add a fd which has
* already O_ASYNC/F_SETSIG set on a duplicate)
*/
/* set async & signal */
if (fcntl(fd, F_SETOWN, my_pid())==-1){
LOG(L_ERR, "ERROR: io_watch_add: fnctl: SETOWN"
" failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
if (fcntl(fd, F_SETSIG, h->signo)==-1){
LOG(L_ERR, "ERROR: io_watch_add: fnctl: SETSIG"
" failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
/* set both non-blocking and async */
set_fd_flags(O_ASYNC| O_NONBLOCK);
#ifdef EXTRA_DEBUG
DBG("io_watch_add: sigio_rt on f %d, signal %d to pid %d\n",
fd, h->signo, my_pid());
#endif
/* empty socket receive buffer, if buffer is already full
* no more space to put packets
* => no more signals are ever generated
* also when moving fds, the freshly moved fd might have
* already some bytes queued, we want to get them now
* and not later -- andrei */
idx=h->fd_no;
check_io=1;
break;
#endif
#ifdef HAVE_EPOLL
case POLL_EPOLL_LT:
ep_event.events=
#ifdef POLLRDHUP
/* listen for EPOLLRDHUP too */
((EPOLLIN|EPOLLRDHUP) & ((int)!(events & POLLIN)-1) ) |
#else /* POLLRDHUP */
(EPOLLIN & ((int)!(events & POLLIN)-1) ) |
#endif /* POLLRDHUP */
(EPOLLOUT & ((int)!(events & POLLOUT)-1) );
ep_event.data.ptr=e;
again1:
n=epoll_ctl(h->epfd, EPOLL_CTL_ADD, fd, &ep_event);
if (unlikely(n==-1)){
if (errno==EAGAIN) goto again1;
LOG(L_ERR, "ERROR: io_watch_add: epoll_ctl failed: %s [%d]\n",
strerror(errno), errno);
goto error;
}
break;
case POLL_EPOLL_ET:
set_fd_flags(O_NONBLOCK);
ep_event.events=
#ifdef POLLRDHUP
/* listen for EPOLLRDHUP too */
((EPOLLIN|EPOLLRDHUP) & ((int)!(events & POLLIN)-1) ) |
#else /* POLLRDHUP */
(EPOLLIN & ((int)!(events & POLLIN)-1) ) |
#endif /* POLLRDHUP */
(EPOLLOUT & ((int)!(events & POLLOUT)-1) ) |
EPOLLET;
ep_event.data.ptr=e;
again2:
n=epoll_ctl(h->epfd, EPOLL_CTL_ADD, fd, &ep_event);
if (unlikely(n==-1)){
if (errno==EAGAIN) goto again2;
LOG(L_ERR, "ERROR: io_watch_add: epoll_ctl failed: %s [%d]\n",
strerror(errno), errno);
goto error;
}
break;
#endif
#ifdef HAVE_KQUEUE
case POLL_KQUEUE:
if (likely( events & POLLIN)){
if (unlikely(kq_ev_change(h, fd, EVFILT_READ, EV_ADD, e)==-1))
goto error;
}
if (unlikely( events & POLLOUT)){
if (unlikely(kq_ev_change(h, fd, EVFILT_WRITE, EV_ADD, e)==-1))
{
if (likely(events & POLLIN)){
kq_ev_change(h, fd, EVFILT_READ, EV_DELETE, 0);
}
}
goto error;
}
break;
#endif
#ifdef HAVE_DEVPOLL
case POLL_DEVPOLL:
pfd.fd=fd;
pfd.events=events;
pfd.revents=0;
again_devpoll:
if (write(h->dpoll_fd, &pfd, sizeof(pfd))==-1){
if (errno==EAGAIN) goto again_devpoll;
LOG(L_ERR, "ERROR: io_watch_add: /dev/poll write failed:"
"%s [%d]\n", strerror(errno), errno);
goto error;
}
break;
#endif
default:
LOG(L_CRIT, "BUG: io_watch_add: no support for poll method "
" %s (%d)\n", poll_method_str[h->poll_method],
h->poll_method);
goto error;
}
h->fd_no++; /* "activate" changes, for epoll/kqueue/devpoll it
has only informative value */
#if defined(HAVE_SIGIO_RT)
if (check_io){
/* handle possible pre-existing events */
pf.fd=fd;
pf.events=events;
check_io_again:
n=0;
while(e->type && ((n=poll(&pf, 1, 0))>0) &&
(handle_io(e, pf.revents, idx)>0) &&
(pf.revents & (e->events|POLLERR|POLLHUP)));
if (unlikely(e->type && (n==-1))){
if (errno==EINTR) goto check_io_again;
LOG(L_ERR, "ERROR: io_watch_add: check_io poll: %s [%d]\n",
strerror(errno), errno);
}
}
#endif
return 0;
error:
if (e) unhash_fd_map(e);
return -1;
#undef fd_array_setup
#undef set_fd_flags
}
#define IO_FD_CLOSING 16
/* parameters: h - handler
* fd - file descriptor
* index - index in the fd_array if known, -1 if not
* (if index==-1 fd_array will be searched for the
* corresponding fd* entry -- slower but unavoidable in
* some cases). index is not used (no fd_array) for epoll,
* /dev/poll and kqueue
* flags - optimization flags, e.g. IO_FD_CLOSING, the fd was
* or will shortly be closed, in some cases we can avoid
* extra remove operations (e.g.: epoll, kqueue, sigio)
* returns 0 if ok, -1 on error */
inline static int io_watch_del(io_wait_h* h, int fd, int idx, int flags)
{
#define fix_fd_array \
do{\
if (unlikely(idx==-1)){ \
/* fix idx if -1 and needed */ \
for (idx=0; (idx<h->fd_no) && \
(h->fd_array[idx].fd!=fd); idx++); \
} \
if (likely(idx<h->fd_no)){ \
memmove(&h->fd_array[idx], &h->fd_array[idx+1], \
(h->fd_no-(idx+1))*sizeof(*(h->fd_array))); \
if ((idx<=h->crt_fd_array_idx) && (h->crt_fd_array_idx>=0)) \
h->crt_fd_array_idx--; \
} \
}while(0)
struct fd_map* e;
int events;
#ifdef HAVE_EPOLL
int n;
struct epoll_event ep_event;
#endif
#ifdef HAVE_DEVPOLL
struct pollfd pfd;
#endif
#ifdef HAVE_SIGIO_RT
int fd_flags;
#endif
if (unlikely((fd<0) || (fd>=h->max_fd_no))){
LOG(L_CRIT, "BUG: io_watch_del: invalid fd %d, not in [0, %d) \n",
fd, h->fd_no);
goto error;
}
DBG("DBG: io_watch_del (%p, %d, %d, 0x%x) fd_no=%d called\n",
h, fd, idx, flags, h->fd_no);
e=get_fd_map(h, fd);
/* more sanity checks */
if (unlikely(e==0)){
LOG(L_CRIT, "BUG: io_watch_del: no corresponding hash entry for %d\n",
fd);
goto error;
}
if (unlikely(e->type==0 /*F_NONE*/)){
LOG(L_ERR, "ERROR: io_watch_del: trying to delete already erased"
" entry %d in the hash(%d, %d, %p) flags %x)\n",
fd, e->fd, e->type, e->data, flags);
goto error;
}
events=e->events;
unhash_fd_map(e);
switch(h->poll_method){
case POLL_POLL:
fix_fd_array;
break;
#ifdef HAVE_SELECT
case POLL_SELECT:
if (likely(events & POLLIN))
FD_CLR(fd, &h->master_rset);
if (unlikely(events & POLLOUT))
FD_CLR(fd, &h->master_wset);
if (unlikely(h->max_fd_select && (h->max_fd_select==fd)))
/* we don't know the prev. max, so we just decrement it */
h->max_fd_select--;
fix_fd_array;
break;
#endif
#ifdef HAVE_SIGIO_RT
case POLL_SIGIO_RT:
fix_fd_array;
/* the O_ASYNC flag must be reset all the time, the fd
* can be changed only if O_ASYNC is reset (if not and
* the fd is a duplicate, you will get signals from the dup. fd
* and not from the original, even if the dup. fd was closed
* and the signals re-set on the original) -- andrei
*/
/*if (!(flags & IO_FD_CLOSING)){*/
/* reset ASYNC */
fd_flags=fcntl(fd, F_GETFL);
if (unlikely(fd_flags==-1)){
LOG(L_ERR, "ERROR: io_watch_del: fnctl: GETFL failed:"
" %s [%d]\n", strerror(errno), errno);
goto error;
}
if (unlikely(fcntl(fd, F_SETFL, fd_flags&(~O_ASYNC))==-1)){
LOG(L_ERR, "ERROR: io_watch_del: fnctl: SETFL"
" failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
break;
#endif
#ifdef HAVE_EPOLL
case POLL_EPOLL_LT:
case POLL_EPOLL_ET:
/* epoll doesn't seem to automatically remove sockets,
* if the socket is a duplicate/moved and the original
* is still open. The fd is removed from the epoll set
* only when the original (and all the copies?) is/are
* closed. This is probably a bug in epoll. --andrei */
#ifdef EPOLL_NO_CLOSE_BUG
if (!(flags & IO_FD_CLOSING)){
#endif
again_epoll:
n=epoll_ctl(h->epfd, EPOLL_CTL_DEL, fd, &ep_event);
if (unlikely(n==-1)){
if (errno==EAGAIN) goto again_epoll;
LOG(L_ERR, "ERROR: io_watch_del: removing fd from epoll "
"list failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
#ifdef EPOLL_NO_CLOSE_BUG
}
#endif
break;
#endif
#ifdef HAVE_KQUEUE
case POLL_KQUEUE:
if (!(flags & IO_FD_CLOSING)){
if (likely(events & POLLIN)){
if (unlikely(kq_ev_change(h, fd, EVFILT_READ,
EV_DELETE, 0) ==-1)){
/* try to delete the write filter anyway */
if (events & POLLOUT){
kq_ev_change(h, fd, EVFILT_WRITE, EV_DELETE, 0);
}
goto error;
}
}
if (unlikely(events & POLLOUT)){
if (unlikely(kq_ev_change(h, fd, EVFILT_WRITE,
EV_DELETE, 0) ==-1))
goto error;
}
}
break;
#endif
#ifdef HAVE_DEVPOLL
case POLL_DEVPOLL:
/* for /dev/poll the closed fds _must_ be removed
(they are not removed automatically on close()) */
pfd.fd=fd;
pfd.events=POLLREMOVE;
pfd.revents=0;
again_devpoll:
if (write(h->dpoll_fd, &pfd, sizeof(pfd))==-1){
if (errno==EINTR) goto again_devpoll;
LOG(L_ERR, "ERROR: io_watch_del: removing fd from "
"/dev/poll failed: %s [%d]\n",
strerror(errno), errno);
goto error;
}
break;
#endif
default:
LOG(L_CRIT, "BUG: io_watch_del: no support for poll method "
" %s (%d)\n", poll_method_str[h->poll_method],
h->poll_method);
goto error;
}
h->fd_no--;
return 0;
error:
return -1;
#undef fix_fd_array
}
/* parameters: h - handler
* fd - file descriptor
* events - new events to watch for
* idx - index in the fd_array if known, -1 if not
* (if index==-1 fd_array will be searched for the
* corresponding fd* entry -- slower but unavoidable in
* some cases). index is not used (no fd_array) for epoll,
* /dev/poll and kqueue
* returns 0 if ok, -1 on error */
inline static int io_watch_chg(io_wait_h* h, int fd, short events, int idx )
{
#define fd_array_chg(ev) \
do{\
if (unlikely(idx==-1)){ \
/* fix idx if -1 and needed */ \
for (idx=0; (idx<h->fd_no) && \
(h->fd_array[idx].fd!=fd); idx++); \
} \
if (likely(idx<h->fd_no)){ \
h->fd_array[idx].events=(ev); \
} \
}while(0)
struct fd_map* e;
int add_events;
int del_events;
#ifdef HAVE_DEVPOLL
struct pollfd pfd;
#endif
#ifdef HAVE_EPOLL
int n;
struct epoll_event ep_event;
#endif
if (unlikely((fd<0) || (fd>=h->max_fd_no))){
LOG(L_CRIT, "BUG: io_watch_chg: invalid fd %d, not in [0, %d) \n",
fd, h->fd_no);
goto error;
}
if (unlikely((events&(POLLIN|POLLOUT))==0)){
LOG(L_CRIT, "BUG: io_watch_chg: invalid events: 0x%0x\n", events);
goto error;
}
DBG("DBG: io_watch_chg (%p, %d, 0x%x, 0x%x) fd_no=%d called\n",
h, fd, events, idx, h->fd_no);
e=get_fd_map(h, fd);
/* more sanity checks */
if (unlikely(e==0)){
LOG(L_CRIT, "BUG: io_watch_chg: no corresponding hash entry for %d\n",
fd);
goto error;
}
if (unlikely(e->type==0 /*F_NONE*/)){
LOG(L_ERR, "ERROR: io_watch_chg: trying to change an already erased"
" entry %d in the hash(%d, %d, %p) )\n",
fd, e->fd, e->type, e->data);
goto error;
}
add_events=events & ~e->events;
del_events=e->events & ~events;
e->events=events;
switch(h->poll_method){
case POLL_POLL:
#ifdef POLLRDHUP
/* listen to POLLRDHUP by default (if POLLIN) */
events|=((int)!(events & POLLIN) - 1) & POLLRDHUP;
#endif /* POLLRDHUP */
fd_array_chg(events);
break;
#ifdef HAVE_SELECT
case POLL_SELECT:
fd_array_chg(events);
if (unlikely(del_events & POLLIN))
FD_CLR(fd, &h->master_rset);
else if (unlikely(add_events & POLLIN))
FD_SET(fd, &h->master_rset);
if (likely(del_events & POLLOUT))
FD_CLR(fd, &h->master_wset);
else if (likely(add_events & POLLOUT))
FD_SET(fd, &h->master_wset);
break;
#endif
#ifdef HAVE_SIGIO_RT
case POLL_SIGIO_RT:
fd_array_chg(events);
/* no need for check_io, since SIGIO_RT listens by default for all
* the events */
break;
#endif
#ifdef HAVE_EPOLL
case POLL_EPOLL_LT:
ep_event.events=
#ifdef POLLRDHUP
/* listen for EPOLLRDHUP too */
((EPOLLIN|EPOLLRDHUP) & ((int)!(events & POLLIN)-1) ) |
#else /* POLLRDHUP */
(EPOLLIN & ((int)!(events & POLLIN)-1) ) |
#endif /* POLLRDHUP */
(EPOLLOUT & ((int)!(events & POLLOUT)-1) );
ep_event.data.ptr=e;
again_epoll_lt:
n=epoll_ctl(h->epfd, EPOLL_CTL_MOD, fd, &ep_event);
if (unlikely(n==-1)){
if (errno==EAGAIN) goto again_epoll_lt;
LOG(L_ERR, "ERROR: io_watch_chg: modifying epoll events"
" failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
break;
case POLL_EPOLL_ET:
ep_event.events=
#ifdef POLLRDHUP
/* listen for EPOLLRDHUP too */
((EPOLLIN|EPOLLRDHUP) & ((int)!(events & POLLIN)-1) ) |
#else /* POLLRDHUP */
(EPOLLIN & ((int)!(events & POLLIN)-1) ) |
#endif /* POLLRDHUP */
(EPOLLOUT & ((int)!(events & POLLOUT)-1) ) |
EPOLLET;
ep_event.data.ptr=e;
again_epoll_et:
n=epoll_ctl(h->epfd, EPOLL_CTL_MOD, fd, &ep_event);
if (unlikely(n==-1)){
if (errno==EAGAIN) goto again_epoll_et;
LOG(L_ERR, "ERROR: io_watch_chg: modifying epoll events"
" failed: %s [%d]\n", strerror(errno), errno);
goto error;
}
break;
#endif
#ifdef HAVE_KQUEUE
case POLL_KQUEUE:
if (unlikely(del_events & POLLIN)){
if (unlikely(kq_ev_change(h, fd, EVFILT_READ,
EV_DELETE, 0) ==-1))
goto error;
}else if (unlikely(add_events & POLLIN)){
if (unlikely(kq_ev_change(h, fd, EVFILT_READ, EV_ADD, e) ==-1))
goto error;
}
if (likely(del_events & POLLOUT)){
if (unlikely(kq_ev_change(h, fd, EVFILT_WRITE,
EV_DELETE, 0) ==-1))
goto error;
}else if (likely(add_events & POLLOUT)){
if (unlikely(kq_ev_change(h, fd, EVFILT_WRITE, EV_ADD, e)==-1))
goto error;
}
break;
#endif
#ifdef HAVE_DEVPOLL
case POLL_DEVPOLL:
/* for /dev/poll the closed fds _must_ be removed
(they are not removed automatically on close()) */
pfd.fd=fd;
pfd.events=POLLREMOVE;
pfd.revents=0;
again_devpoll1:
if (unlikely(write(h->dpoll_fd, &pfd, sizeof(pfd))==-1)){
if (errno==EINTR) goto again_devpoll1;
LOG(L_ERR, "ERROR: io_watch_chg: removing fd from "
"/dev/poll failed: %s [%d]\n",
strerror(errno), errno);
goto error;
}
again_devpoll2:
pfd.events=events;
pfd.revents=0;
if (unlikely(write(h->dpoll_fd, &pfd, sizeof(pfd))==-1)){
if (errno==EINTR) goto again_devpoll2;
LOG(L_ERR, "ERROR: io_watch_chg: re-adding fd to "
"/dev/poll failed: %s [%d]\n",
strerror(errno), errno);
goto error;
}
break;
#endif
default:
LOG(L_CRIT, "BUG: io_watch_chg: no support for poll method "
" %s (%d)\n", poll_method_str[h->poll_method],
h->poll_method);
goto error;
}
return 0;
error:
return -1;
#undef fix_fd_array
}
/* io_wait_loop_x style function
* wait for io using poll()
* params: h - io_wait handle
* t - timeout in s
* repeat - if !=0 handle_io will be called until it returns <=0
* returns: number of IO events handled on success (can be 0), -1 on error
*/
inline static int io_wait_loop_poll(io_wait_h* h, int t, int repeat)
{
int n, r;
int ret;
struct fd_map* fm;
again:
ret=n=poll(h->fd_array, h->fd_no, t*1000);
if (n==-1){
if (errno==EINTR) goto again; /* signal, ignore it */
else{
LOG(L_ERR, "ERROR:io_wait_loop_poll: poll: %s [%d]\n",
strerror(errno), errno);
goto error;
}
}
for (r=0; (r<h->fd_no) && n; r++){
fm=get_fd_map(h, h->fd_array[r].fd);
if (h->fd_array[r].revents & (fm->events|POLLERR|POLLHUP)){
n--;
/* sanity checks */
if (unlikely((h->fd_array[r].fd >= h->max_fd_no)||
(h->fd_array[r].fd < 0))){
LOG(L_CRIT, "BUG: io_wait_loop_poll: bad fd %d "
"(no in the 0 - %d range)\n",
h->fd_array[r].fd, h->max_fd_no);
/* try to continue anyway */
h->fd_array[r].events=0; /* clear the events */
continue;
}
h->crt_fd_array_idx=r;
/* repeat handle_io if repeat, fd still watched (not deleted
* inside handle_io), handle_io returns that there's still
* IO and the fd is still watched for the triggering event */
while(fm->type &&
(handle_io(fm, h->fd_array[r].revents, r) > 0) &&
repeat && ((fm->events|POLLERR|POLLHUP) &
h->fd_array[r].revents));
r=h->crt_fd_array_idx; /* can change due to io_watch_del(fd)
array shifting */
}
}
error:
return ret;
}
#ifdef HAVE_SELECT
/* wait for io using select */
inline static int io_wait_loop_select(io_wait_h* h, int t, int repeat)
{
fd_set sel_rset;
fd_set sel_wset;
int n, ret;
struct timeval timeout;
int r;
struct fd_map* fm;
int revents;
again:
sel_rset=h->master_rset;
sel_wset=h->master_wset;
timeout.tv_sec=t;
timeout.tv_usec=0;
ret=n=select(h->max_fd_select+1, &sel_rset, &sel_wset, 0, &timeout);
if (n<0){
if (errno==EINTR) goto again; /* just a signal */
LOG(L_ERR, "ERROR: io_wait_loop_select: select: %s [%d]\n",
strerror(errno), errno);
n=0;
/* continue */
}
/* use poll fd array */
for(r=0; (r<h->fd_no) && n; r++){
revents=0;
if (likely(FD_ISSET(h->fd_array[r].fd, &sel_rset)))
revents|=POLLIN;
if (unlikely(FD_ISSET(h->fd_array[r].fd, &sel_wset)))
revents|=POLLOUT;
if (unlikely(revents)){
h->crt_fd_array_idx=r;
fm=get_fd_map(h, h->fd_array[r].fd);
while(fm->type && (fm->events & revents) &&
(handle_io(fm, revents, r)>0) && repeat);
r=h->crt_fd_array_idx; /* can change due to io_watch_del(fd)
array shifting */
n--;
}
};
return ret;
}
#endif
#ifdef HAVE_EPOLL
inline static int io_wait_loop_epoll(io_wait_h* h, int t, int repeat)
{
int n, r;
struct fd_map* fm;
int revents;
again:
n=epoll_wait(h->epfd, h->ep_array, h->fd_no, t*1000);
if (unlikely(n==-1)){
if (errno==EINTR) goto again; /* signal, ignore it */
else{
LOG(L_ERR, "ERROR:io_wait_loop_epoll: "
"epoll_wait(%d, %p, %d, %d): %s [%d]\n",
h->epfd, h->ep_array, h->fd_no, t*1000,
strerror(errno), errno);
goto error;
}
}
#if 0
if (n>1){
for(r=0; r<n; r++){
LOG(L_ERR, "WARNING: ep_array[%d]= %x, %p\n",
r, h->ep_array[r].events, h->ep_array[r].data.ptr);
}
}
#endif
for (r=0; r<n; r++){
revents= (POLLIN & (!(h->ep_array[r].events & (EPOLLIN|EPOLLPRI))
-1)) |
(POLLOUT & (!(h->ep_array[r].events & EPOLLOUT)-1)) |
(POLLERR & (!(h->ep_array[r].events & EPOLLERR)-1)) |
(POLLHUP & (!(h->ep_array[r].events & EPOLLHUP)-1))
#ifdef POLLRDHUP
| (POLLRDHUP & (!(h->ep_array[r].events & EPOLLRDHUP)-1))
#endif
;
if (likely(revents)){
fm=(struct fd_map*)h->ep_array[r].data.ptr;
while(fm->type && ((fm->events|POLLERR|POLLHUP) & revents) &&
(handle_io(fm, revents, -1)>0) && repeat);
}else{
LOG(L_ERR, "ERROR:io_wait_loop_epoll: unexpected event %x"
" on %d/%d, data=%p\n", h->ep_array[r].events,
r+1, n, h->ep_array[r].data.ptr);
}
}
error:
return n;
}
#endif
#ifdef HAVE_KQUEUE
inline static int io_wait_loop_kqueue(io_wait_h* h, int t, int repeat)
{
int n, r;
struct timespec tspec;
struct fd_map* fm;
int revents;
tspec.tv_sec=t;
tspec.tv_nsec=0;
again:
n=kevent(h->kq_fd, h->kq_changes, h->kq_nchanges, h->kq_array,
h->fd_no, &tspec);
if (unlikely(n==-1)){
if (errno==EINTR) goto again; /* signal, ignore it */
else{
LOG(L_ERR, "ERROR: io_wait_loop_kqueue: kevent:"
" %s [%d]\n", strerror(errno), errno);
goto error;
}
}
h->kq_nchanges=0; /* reset changes array */
for (r=0; r<n; r++){
#ifdef EXTRA_DEBUG
DBG("DBG: kqueue: event %d/%d: fd=%d, udata=%lx, flags=0x%x\n",
r, n, h->kq_array[r].ident, (long)h->kq_array[r].udata,
h->kq_array[r].flags);
#endif
#if 0
if (unlikely(h->kq_array[r].flags & EV_ERROR)){
/* error in changes: we ignore it, it can be caused by
trying to remove an already closed fd: race between
adding something to the changes array, close() and
applying the changes */
LOG(L_INFO, "INFO: io_wait_loop_kqueue: kevent error on "
"fd %ld: %s [%ld]\n", h->kq_array[r].ident,
strerror(h->kq_array[r].data),
(long)h->kq_array[r].data);
}else{
#endif
fm=(struct fd_map*)h->kq_array[r].udata;
if (likely(h->kq_array[r].filter==EVFILT_READ)){
revents=POLLIN |
(((int)!(h->kq_array[r].flags & EV_EOF)-1)&POLLHUP);
while(fm->type && (fm->events & revents) &&
(handle_io(fm, revents, -1)>0) && repeat);
}else if (h->kq_array[r].filter==EVFILT_WRITE){
revents=POLLOUT |
(((int)!(h->kq_array[r].flags & EV_EOF)-1)&POLLHUP);
while(fm->type && (fm->events & revents) &&
(handle_io(fm, revents, -1)>0) && repeat);
}
/*} */
}
error:
return n;
}
#endif
#ifdef HAVE_SIGIO_RT
/* sigio rt version has no repeat (it doesn't make sense)*/
inline static int io_wait_loop_sigio_rt(io_wait_h* h, int t)
{
int n;
int ret;
struct timespec ts;
siginfo_t siginfo;
int sigio_band;
int sigio_fd;
struct fd_map* fm;
int revents;
#ifdef SIGINFO64_WORKARROUND
int* pi;
#endif
ret=1; /* 1 event per call normally */
ts.tv_sec=t;
ts.tv_nsec=0;
if (unlikely(!sigismember(&h->sset, h->signo) ||
!sigismember(&h->sset, SIGIO))) {
LOG(L_CRIT, "BUG: io_wait_loop_sigio_rt: the signal mask"
" is not properly set!\n");
goto error;
}
again:
n=sigtimedwait(&h->sset, &siginfo, &ts);
if (unlikely(n==-1)){
if (errno==EINTR) goto again; /* some other signal, ignore it */
else if (errno==EAGAIN){ /* timeout */
ret=0;
goto end;
}else{
LOG(L_ERR, "ERROR: io_wait_loop_sigio_rt: sigtimed_wait"
" %s [%d]\n", strerror(errno), errno);
goto error;
}
}
if (likely(n!=SIGIO)){
#ifdef SIGINFO64_WORKARROUND
/* on linux siginfo.si_band is defined as long in userspace
* and as int in kernel (< 2.6.5) => on 64 bits things will break!
* (si_band will include si_fd, and si_fd will contain
* garbage).
* see /usr/src/linux/include/asm-generic/siginfo.h and
* /usr/include/bits/siginfo.h
* On newer kernels this is fixed (si_band is long in the kernel too).
* -- andrei */
if ((_os_ver<0x020605) && (sizeof(siginfo.si_band)>sizeof(int))){
pi=(int*)(void*)&siginfo.si_band; /* avoid type punning warnings */
sigio_band=*pi;
sigio_fd=*(pi+1);
}else
#endif
{
sigio_band=siginfo.si_band;
sigio_fd=siginfo.si_fd;
}
if (unlikely(siginfo.si_code==SI_SIGIO)){
/* old style, we don't know the event (linux 2.2.?) */
LOG(L_WARN, "WARNING: io_wait_loop_sigio_rt: old style sigio"
" interface\n");
fm=get_fd_map(h, sigio_fd);
/* we can have queued signals generated by fds not watched
* any more, or by fds in transition, to a child => ignore them*/
if (fm->type)
handle_io(fm, POLLIN|POLLOUT, -1);
}else{
/* si_code contains the SIGPOLL reason: POLL_IN, POLL_OUT,
* POLL_MSG, POLL_ERR, POLL_PRI or POLL_HUP
* and si_band the translated poll event bitmap:
* POLLIN|POLLRDNORM (=POLL_IN),
* POLLOUT|POLLWRNORM|POLLWRBAND (=POLL_OUT),
* POLLIN|POLLRDNORM|POLLMSG (=POLL_MSG),
* POLLERR (=POLL_ERR),
* POLLPRI|POLLRDBAND (=POLL_PRI),
* POLLHUP|POLLERR (=POLL_HUP)
* [linux 2.6.22 fs/fcntl.c:447]
*/
#ifdef EXTRA_DEBUG
DBG("io_wait_loop_sigio_rt: siginfo: signal=%d (%d),"
" si_code=%d, si_band=0x%x,"
" si_fd=%d\n",
siginfo.si_signo, n, siginfo.si_code,
(unsigned)sigio_band,
sigio_fd);
#endif
/* on some errors (e.g. when receving TCP RST), sigio_band will
* be set to 0x08 (POLLERR) or 0x18 (POLLERR|POLLHUP - on stream
* unix socket close) , so better catch all events --andrei */
if (likely(sigio_band)){
fm=get_fd_map(h, sigio_fd);
revents=sigio_band;
/* fix revents==POLLPRI case */
revents |= (!(revents & POLLPRI)-1) & POLLIN;
/* we can have queued signals generated by fds not watched
* any more, or by fds in transition, to a child
* => ignore them */
if (fm->type && ((fm->events|POLLERR|POLLHUP) & revents))
handle_io(fm, revents, -1);
else
DBG("WARNING: io_wait_loop_sigio_rt: ignoring event"
" %x on fd %d, watching for %x, si_code=%x "
"(fm->type=%d, fm->fd=%d, fm->data=%p)\n",
sigio_band, sigio_fd, fm->events, siginfo.si_code,
fm->type, fm->fd, fm->data);
}else{
LOG(L_ERR, "ERROR: io_wait_loop_sigio_rt: unexpected event"
" on fd %d: %x\n", sigio_fd, sigio_band);
}
}
}else{
/* signal queue overflow
* TODO: increase signal queue size: 2.4x /proc/.., 2.6x -rlimits */
LOG(L_WARN, "WARNING: io_wait_loop_sigio_rt: signal queue overflowed"
"- falling back to poll\n");
/* clear real-time signal queue
* both SIG_IGN and SIG_DFL are needed , it doesn't work
* only with SIG_DFL */
if (signal(h->signo, SIG_IGN)==SIG_ERR){
LOG(L_CRIT, "BUG: do_poll: couldn't reset signal to IGN\n");
}
if (signal(h->signo, SIG_DFL)==SIG_ERR){
LOG(L_CRIT, "BUG: do_poll: couldn't reset signal to DFL\n");
}
/* falling back to normal poll */
ret=io_wait_loop_poll(h, -1, 1);
}
end:
return ret;
error:
return -1;
}
#endif
#ifdef HAVE_DEVPOLL
inline static int io_wait_loop_devpoll(io_wait_h* h, int t, int repeat)
{
int n, r;
int ret;
struct dvpoll dpoll;
struct fd_map* fm;
dpoll.dp_timeout=t*1000;
dpoll.dp_nfds=h->fd_no;
dpoll.dp_fds=h->fd_array;
again:
ret=n=ioctl(h->dpoll_fd, DP_POLL, &dpoll);
if (unlikely(n==-1)){
if (errno==EINTR) goto again; /* signal, ignore it */
else{
LOG(L_ERR, "ERROR:io_wait_loop_devpoll: ioctl: %s [%d]\n",
strerror(errno), errno);
goto error;
}
}
for (r=0; r< n; r++){
if (h->fd_array[r].revents & (POLLNVAL|POLLERR)){
LOG(L_ERR, "ERROR: io_wait_loop_devpoll: pollinval returned"
" for fd %d, revents=%x\n",
h->fd_array[r].fd, h->fd_array[r].revents);
}
/* POLLIN|POLLHUP just go through */
fm=get_fd_map(h, h->fd_array[r].fd);
while(fm->type && (fm->events & h->fd_array[r].revents) &&
(handle_io(fm, h->fd_array[r].revents, r) > 0) && repeat);
}
error:
return ret;
}
#endif
/* init */
/* initializes the static vars/arrays
* params: h - pointer to the io_wait_h that will be initialized
* max_fd - maximum allowed fd number
* poll_m - poll method (0 for automatic best fit)
*/
int init_io_wait(io_wait_h* h, int max_fd, enum poll_types poll_method);
/* destroys everything init_io_wait allocated */
void destroy_io_wait(io_wait_h* h);
#endif