asterisk/main/io.c

469 lines
10 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Copyright (C) 1999 - 2005, Digium, Inc.
*
* Mark Spencer <markster@digium.com>
*
* See http://www.asterisk.org for more information about
* the Asterisk project. Please do not directly contact
* any of the maintainers of this project for assistance;
* the project provides a web site, mailing lists and IRC
* channels for your use.
*
* This program is free software, distributed under the terms of
* the GNU General Public License Version 2. See the LICENSE file
* at the top of the source tree.
*/
/*! \file
*
* \brief I/O Management (Derived from Cheops-NG)
*
* \author Mark Spencer <markster@digium.com>
*/
/*** MODULEINFO
<support_level>core</support_level>
***/
#include "asterisk.h"
#include <termios.h>
#include <sys/ioctl.h>
#include "asterisk/io.h"
#include "asterisk/utils.h"
#ifdef HAVE_SYSTEMD
#include <systemd/sd-daemon.h>
#ifndef SD_LISTEN_FDS_START
#define SD_LISTEN_FDS_START 3
#endif
#endif
#ifdef DEBUG_IO
#define DEBUG DEBUG_M
#else
#define DEBUG(a)
#endif
/*! \brief
* Kept for each file descriptor
*/
struct io_rec {
ast_io_cb callback; /*!< What is to be called */
void *data; /*!< Data to be passed */
int *id; /*!< ID number */
};
/* These two arrays are keyed with
the same index. it's too bad that
pollfd doesn't have a callback field
or something like that. They grow as
needed, by GROW_SHRINK_SIZE structures
at once */
#define GROW_SHRINK_SIZE 512
/*! \brief Global IO variables are now in a struct in order to be
made threadsafe */
struct io_context {
struct pollfd *fds; /*!< Poll structure */
struct io_rec *ior; /*!< Associated I/O records */
unsigned int fdcnt; /*!< First available fd */
unsigned int maxfdcnt; /*!< Maximum available fd */
int current_ioc; /*!< Currently used io callback */
int needshrink; /*!< Whether something has been deleted */
};
/*! \brief Create an I/O context */
struct io_context *io_context_create(void)
{
struct io_context *tmp = NULL;
if (!(tmp = ast_malloc(sizeof(*tmp))))
return NULL;
tmp->needshrink = 0;
tmp->fdcnt = 0;
tmp->maxfdcnt = GROW_SHRINK_SIZE/2;
tmp->current_ioc = -1;
if (!(tmp->fds = ast_calloc(1, (GROW_SHRINK_SIZE / 2) * sizeof(*tmp->fds)))) {
ast_free(tmp);
tmp = NULL;
} else {
if (!(tmp->ior = ast_calloc(1, (GROW_SHRINK_SIZE / 2) * sizeof(*tmp->ior)))) {
ast_free(tmp->fds);
ast_free(tmp);
tmp = NULL;
}
}
return tmp;
}
void io_context_destroy(struct io_context *ioc)
{
/* Free associated memory with an I/O context */
if (ioc->fds)
ast_free(ioc->fds);
if (ioc->ior)
ast_free(ioc->ior);
ast_free(ioc);
}
/*! \brief
* Grow the size of our arrays.
* \retval 0 on success
* \retval -1 on failure
*/
static int io_grow(struct io_context *ioc)
{
void *tmp;
DEBUG(ast_debug(1, "io_grow()\n"));
ioc->maxfdcnt += GROW_SHRINK_SIZE;
if ((tmp = ast_realloc(ioc->ior, (ioc->maxfdcnt + 1) * sizeof(*ioc->ior)))) {
ioc->ior = tmp;
if ((tmp = ast_realloc(ioc->fds, (ioc->maxfdcnt + 1) * sizeof(*ioc->fds)))) {
ioc->fds = tmp;
} else {
/*
* Failed to allocate enough memory for the pollfd. Not
* really any need to shrink back the iorec's as we'll
* probably want to grow them again soon when more memory
* is available, and then they'll already be the right size
*/
ioc->maxfdcnt -= GROW_SHRINK_SIZE;
return -1;
}
} else {
/*
* Memory allocation failure. We return to the old size, and
* return a failure
*/
ioc->maxfdcnt -= GROW_SHRINK_SIZE;
return -1;
}
return 0;
}
/*! \brief
* Add a new I/O entry for this file descriptor
* with the given event mask, to call callback with
* data as an argument.
*/
int *ast_io_add(struct io_context *ioc, int fd, ast_io_cb callback, short events, void *data)
{
int *ret;
DEBUG(ast_debug(1, "ast_io_add()\n"));
if (ioc->fdcnt >= ioc->maxfdcnt) {
/*
* We don't have enough space for this entry. We need to
* reallocate maxfdcnt poll fd's and io_rec's, or back out now.
*/
if (io_grow(ioc))
return NULL;
}
/*
* At this point, we've got sufficiently large arrays going
* and we can make an entry for it in the pollfd and io_r
* structures.
*/
ioc->fds[ioc->fdcnt].fd = fd;
ioc->fds[ioc->fdcnt].events = events;
ioc->fds[ioc->fdcnt].revents = 0;
ioc->ior[ioc->fdcnt].callback = callback;
ioc->ior[ioc->fdcnt].data = data;
if (!(ioc->ior[ioc->fdcnt].id = ast_malloc(sizeof(*ioc->ior[ioc->fdcnt].id)))) {
/* Bonk if we couldn't allocate an int */
return NULL;
}
*(ioc->ior[ioc->fdcnt].id) = ioc->fdcnt;
ret = ioc->ior[ioc->fdcnt].id;
ioc->fdcnt++;
return ret;
}
int *ast_io_change(struct io_context *ioc, int *id, int fd, ast_io_cb callback, short events, void *data)
{
/* If this id exceeds our file descriptor count it doesn't exist here */
if (*id > ioc->fdcnt)
return NULL;
if (fd > -1)
ioc->fds[*id].fd = fd;
if (callback)
ioc->ior[*id].callback = callback;
if (events)
ioc->fds[*id].events = events;
if (data)
ioc->ior[*id].data = data;
return id;
}
static int io_shrink(struct io_context *ioc)
{
int getfrom, putto = 0;
/*
* Bring the fields from the very last entry to cover over
* the entry we are removing, then decrease the size of the
* arrays by one.
*/
for (getfrom = 0; getfrom < ioc->fdcnt; getfrom++) {
if (ioc->ior[getfrom].id) {
/* In use, save it */
if (getfrom != putto) {
ioc->fds[putto] = ioc->fds[getfrom];
ioc->ior[putto] = ioc->ior[getfrom];
*(ioc->ior[putto].id) = putto;
}
putto++;
}
}
ioc->fdcnt = putto;
ioc->needshrink = 0;
/* FIXME: We should free some memory if we have lots of unused
io structs */
return 0;
}
int ast_io_remove(struct io_context *ioc, int *_id)
{
int x;
if (!_id) {
ast_log(LOG_WARNING, "Asked to remove NULL?\n");
return -1;
}
for (x = 0; x < ioc->fdcnt; x++) {
if (ioc->ior[x].id == _id) {
/* Free the int immediately and set to NULL so we know it's unused now */
ast_free(ioc->ior[x].id);
ioc->ior[x].id = NULL;
ioc->fds[x].events = 0;
ioc->fds[x].revents = 0;
ioc->needshrink = 1;
if (ioc->current_ioc == -1)
io_shrink(ioc);
return 0;
}
}
ast_log(LOG_NOTICE, "Unable to remove unknown id %p\n", _id);
return -1;
}
/*! \brief
* Make the poll call, and call
* the callbacks for anything that needs
* to be handled
*/
int ast_io_wait(struct io_context *ioc, int howlong)
{
int res, x, origcnt;
DEBUG(ast_debug(1, "ast_io_wait()\n"));
if ((res = ast_poll(ioc->fds, ioc->fdcnt, howlong)) <= 0) {
return res;
}
/* At least one event tripped */
origcnt = ioc->fdcnt;
for (x = 0; x < origcnt; x++) {
/* Yes, it is possible for an entry to be deleted and still have an
event waiting if it occurs after the original calling id */
if (ioc->fds[x].revents && ioc->ior[x].id) {
/* There's an event waiting */
ioc->current_ioc = *ioc->ior[x].id;
if (ioc->ior[x].callback) {
if (!ioc->ior[x].callback(ioc->ior[x].id, ioc->fds[x].fd, ioc->fds[x].revents, ioc->ior[x].data)) {
/* Time to delete them since they returned a 0 */
ast_io_remove(ioc, ioc->ior[x].id);
}
}
ioc->current_ioc = -1;
}
}
if (ioc->needshrink)
io_shrink(ioc);
return res;
}
void ast_io_dump(struct io_context *ioc)
{
/*
* Print some debugging information via
* the logger interface
*/
int x;
ast_debug(1, "Asterisk IO Dump: %u entries, %u max entries\n", ioc->fdcnt, ioc->maxfdcnt);
ast_debug(1, "================================================\n");
ast_debug(1, "| ID FD Callback Data Events |\n");
ast_debug(1, "+------+------+-----------+-----------+--------+\n");
for (x = 0; x < ioc->fdcnt; x++) {
ast_debug(1, "| %.4d | %.4d | %p | %p | %.6x |\n",
*ioc->ior[x].id,
ioc->fds[x].fd,
ioc->ior[x].callback,
ioc->ior[x].data,
(unsigned)ioc->fds[x].events);
}
ast_debug(1, "================================================\n");
}
/* Unrelated I/O functions */
int ast_hide_password(int fd)
{
struct termios tios;
int res;
int old;
if (!isatty(fd))
return -1;
res = tcgetattr(fd, &tios);
if (res < 0)
return -1;
old = tios.c_lflag & (ECHO | ECHONL);
tios.c_lflag &= ~ECHO;
tios.c_lflag |= ECHONL;
res = tcsetattr(fd, TCSAFLUSH, &tios);
if (res < 0)
return -1;
return old;
}
int ast_restore_tty(int fd, int oldstate)
{
int res;
struct termios tios;
if (oldstate < 0)
return 0;
res = tcgetattr(fd, &tios);
if (res < 0)
return -1;
tios.c_lflag &= ~(ECHO | ECHONL);
tios.c_lflag |= oldstate;
res = tcsetattr(fd, TCSAFLUSH, &tios);
if (res < 0)
return -1;
return 0;
}
int ast_get_termcols(int fd)
{
struct winsize win;
int cols = 0;
if (!isatty(fd))
return -1;
if ( ioctl(fd, TIOCGWINSZ, &win) != -1 ) {
if ( !cols && win.ws_col > 0 )
cols = (int) win.ws_col;
} else {
/* assume 80 characters if the ioctl fails for some reason */
cols = 80;
}
return cols;
}
int ast_sd_notify(const char *state) {
#ifdef HAVE_SYSTEMD
return sd_notify(0, state);
#else
return 0;
#endif
}
#ifdef HAVE_SYSTEMD
/*!
* \internal \brief Check the type and sockaddr of a file descriptor.
* \param fd File Descriptor to check.
* \param type SOCK_STREAM or SOCK_DGRAM
* \param addr The socket address to match.
* \retval 0 if matching
* \retval -1 if not matching
*/
static int ast_sd_is_socket_sockaddr(int fd, int type, const struct ast_sockaddr* addr)
{
int canretry = 1;
struct ast_sockaddr fd_addr;
struct sockaddr ss;
socklen_t ss_len;
if (sd_is_socket(fd, AF_UNSPEC, type, 1) <= 0) {
return -1;
}
doretry:
if (getsockname(fd, &ss, &ss_len) != 0) {
return -1;
}
if (ss.sa_family == AF_UNSPEC && canretry) {
/* An unknown bug can cause silent failure from
* the first call to getsockname. */
canretry = 0;
goto doretry;
}
ast_sockaddr_copy_sockaddr(&fd_addr, &ss, ss_len);
return ast_sockaddr_cmp(addr, &fd_addr);
}
#endif
int ast_sd_get_fd(int type, const struct ast_sockaddr *addr)
{
#ifdef HAVE_SYSTEMD
int count = sd_listen_fds(0);
int idx;
for (idx = 0; idx < count; idx++) {
if (!ast_sd_is_socket_sockaddr(idx + SD_LISTEN_FDS_START, type, addr)) {
return idx + SD_LISTEN_FDS_START;
}
}
#endif
return -1;
}
int ast_sd_get_fd_un(int type, const char *path)
{
#ifdef HAVE_SYSTEMD
int count = sd_listen_fds(0);
int idx;
for (idx = 0; idx < count; idx++) {
if (sd_is_socket_unix(idx + SD_LISTEN_FDS_START, type, 1, path, 0) > 0) {
return idx + SD_LISTEN_FDS_START;
}
}
#endif
return -1;
}