sigemptyset(&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGINT, &act, NULL);
- sched.select_function = i9e_select;
+ sched.poll_function = i9e_poll;
sched.default_timeout = 1000;
ret = i9e_open(&ici, &sched);
* This is needed also in audiod_command.c (for the tasks command), so it can
* not be made static.
*/
-struct sched sched = {.max_fileno = 0};
+struct sched sched = {.timeout = 0};
/* The task for obtaining para_server's status (para_client stat). */
struct status_task {
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGINT, &act, NULL);
- sched.select_function = i9e_select;
+ sched.poll_function = i9e_poll;
ret = i9e_open(&ici, &sched);
if (ret < 0)
#include <sys/types.h>
#include <dirent.h>
#include <sys/mman.h>
-#include <poll.h>
#include "para.h"
#include "error.h"
return !stat(fn, &statbuf);
}
-/**
- * Paraslash's wrapper for select(2).
- *
- * It calls select(2) (with no exceptfds) and starts over if select() was
- * interrupted by a signal.
- *
- * \param n The highest-numbered descriptor in any of the two sets, plus 1.
- * \param readfds fds that should be checked for readability.
- * \param writefds fds that should be checked for writablility.
- * \param timeout Upper bound in milliseconds.
- *
- * \return The return value of the underlying select() call on success, the
- * negative system error code on errors.
- *
- * All arguments are passed verbatim to select(2).
- * \sa select(2) select_tut(2).
- */
-int para_select(int n, fd_set *readfds, fd_set *writefds, int timeout)
-{
- int ret;
- struct timeval tv;
-
- ms2tv(timeout, &tv);
- do
- ret = select(n, readfds, writefds, NULL, &tv);
- while (ret < 0 && errno == EINTR);
- if (ret < 0)
- return -ERRNO_TO_PARA_ERROR(errno);
- return ret;
-}
-
/**
* Set a file descriptor to blocking mode.
*
return -ERRNO_TO_PARA_ERROR(err);
}
-static int xpoll(struct pollfd *fds, nfds_t nfds, int timeout)
+/**
+ * Simple wrapper for poll(2).
+ *
+ * It calls poll(2) and starts over if the call was interrupted by a signal.
+ *
+ * \param fds See poll(2).
+ * \param nfds See poll(2).
+ * \param timeout See poll(2).
+ *
+ * \return The return value of the underlying poll() call on success, the
+ * negative paraslash error code on errors.
+ *
+ * All arguments are passed verbatim to poll(2).
+ */
+int xpoll(struct pollfd *fds, nfds_t nfds, int timeout)
{
int ret;
int write_all(int fd, const char *buf, size_t len);
__printf_2_3 int write_va_buffer(int fd, const char *fmt, ...);
bool file_exists(const char *);
-int para_select(int n, fd_set *readfds, fd_set *writefds, int timeout);
+int xpoll(struct pollfd *fds, nfds_t nfds, int timeout);
__must_check int mark_fd_nonblocking(int fd);
__must_check int mark_fd_blocking(int fd);
int para_mmap(size_t length, int prot, int flags, int fd, void *map);
}
/**
- * Wrapper for select(2) which does not restart on interrupts.
+ * Wrapper for poll(2) which handles EINTR and returns paraslash error codes.
*
- * \param n \sa \ref para_select().
- * \param readfds \sa \ref para_select().
- * \param writefds \sa \ref para_select().
- * \param timeout \sa \ref para_select().
+ * \param fds See poll(2).
+ * \param nfds See poll(2).
+ * \param timeout See poll(2).
*
- * \return \sa \ref para_select().
+ * \return See poll(2).
*
- * The only difference between this function and \ref para_select() is that
- * \ref i9e_select() returns zero if the select call returned \p EINTR.
+ * The only difference between this function and \ref xpoll() is that \ref
+ * i9e_poll() returns zero if the system call was interrupted while xpoll()
+ * restarts the system call in this case.
*/
-int i9e_select(int n, fd_set *readfds, fd_set *writefds, int timeout)
+int i9e_poll(struct pollfd *fds, nfds_t nfds, int timeout)
{
- struct timeval tv;
- int ret;
-
- ms2tv(timeout, &tv);
- ret = select(n, readfds, writefds, NULL, &tv);
-
+ int ret = poll(fds, nfds, timeout);
if (ret < 0) {
if (errno == EINTR)
ret = 0;
void i9e_close(void);
void i9e_signal_dispatch(int sig_num);
__printf_2_3 void i9e_log(int ll, const char* fmt,...);
-int i9e_select(int n, fd_set *readfds, fd_set *writefds, int timeout);
+int i9e_poll(struct pollfd *fds, nfds_t nfds, int timeout);
int i9e_extract_completions(const char *word, char **string_list,
char ***result);
char **i9e_complete_commands(const char *word, struct i9e_completer *completers);
#include <stdbool.h>
#include <inttypes.h>
#include <sys/uio.h>
+#include <poll.h>
+
#include "gcc-compat.h"
/** used in various contexts */
char *stat_item_values[NUM_STAT_ITEMS] = {NULL};
-static struct sched sched = {.max_fileno = 0};
+static struct sched sched;
static struct play_task play_task, *pt = &play_task;
#define AFH_RECV_CMD (lls_cmd(LSG_RECV_CMD_CMD_AFH, recv_cmd_suite))
sigemptyset(&act.sa_mask);
act.sa_flags = 0;
sigaction(SIGWINCH, &act, NULL);
- sched.select_function = i9e_select;
+ sched.poll_function = i9e_poll;
ici.bound_keyseqs = get_mapped_keyseqs();
pt->btrn = ici.producer = btr_new_node(&(struct btr_node_description)
*
* \param s Pointer to the scheduler struct.
*
- * This function updates the global \a now pointer, calls all registered
+ * This function updates the global now pointer, calls all registered
* pre_monitor hooks which may set the timeout and add any file descriptors to
- * the fd sets of \a s. Next, it calls para_select() and makes the result
+ * the pollfd array. Next, it calls the poll function and makes the result
* available to the registered tasks by calling their post_monitor hook.
*
* \return Zero if no more tasks are left in the task list, negative if the
- * select function returned an error.
+ * poll function returned an error.
*
* \sa \ref now.
*/
int ret;
unsigned num_running_tasks;
- if (!s->select_function)
- s->select_function = para_select;
+ if (!s->poll_function)
+ s->poll_function = xpoll;
again:
- FD_ZERO(&s->rfds);
- FD_ZERO(&s->wfds);
+ s->num_pfds = 0;
+ if (s->pidx)
+ memset(s->pidx, 0xff, s->pidx_array_len * sizeof(unsigned));
s->timeout = s->default_timeout;
- s->max_fileno = -1;
clock_get_realtime(&now_struct);
sched_pre_monitor(s);
- ret = s->select_function(s->max_fileno + 1, &s->rfds, &s->wfds,
- s->timeout);
+ ret = s->poll_function(s->pfd, s->num_pfds, s->timeout);
if (ret < 0)
return ret;
- if (ret == 0) {
- /*
- * APUE: Be careful not to check the descriptor sets on return
- * unless the return value is greater than zero. The return
- * state of the descriptor sets is implementation dependent if
- * either a signal is caught or the timer expires.
- */
- FD_ZERO(&s->rfds);
- FD_ZERO(&s->wfds);
- }
clock_get_realtime(&now_struct);
num_running_tasks = sched_post_monitor(s);
if (num_running_tasks == 0)
t->name);
unlink_and_free_task(t);
}
+ free(s->pfd);
+ free(s->pidx);
}
/**
}
/**
- * Set the select timeout to the minimal possible value.
+ * Set the I/O timeout to the minimal possible value.
*
* \param s Pointer to the scheduler struct.
*
- * This causes the next select() call to return immediately.
+ * This causes the next poll() call to return immediately.
*/
void sched_min_delay(struct sched *s)
{
}
/**
- * Impose an upper bound for the timeout of the next select() call.
+ * Impose an upper bound for the I/O timeout.
*
* \param to Maximal allowed timeout.
* \param s Pointer to the scheduler struct.
*
- * If the current scheduler timeout is already smaller than \a to, this
- * function does nothing. Otherwise the timeout for the next select() call is
- * set to the given value.
+ * If the current I/O timeout is already smaller than to, this function does
+ * nothing. Otherwise the timeout is set to the given value.
*
* \sa \ref sched_request_timeout_ms().
*/
}
/**
- * Force the next select() call to return before the given amount of milliseconds.
+ * Bound the I/O timeout to at most the given amount of milliseconds.
*
* \param ms The maximal allowed timeout in milliseconds.
* \param s Pointer to the scheduler struct.
*
- * Like sched_request_timeout() this imposes an upper bound on the timeout
- * value for the next select() call.
+ * Like \ref sched_request_timeout() this imposes an upper bound on the I/O
+ * timeout.
*/
void sched_request_timeout_ms(long unsigned ms, struct sched *s)
{
}
/**
- * Force the next select() call to return before the given future time.
+ * Bound the I/O timeout by an absolute time in the future.
*
- * \param barrier Absolute time before select() should return.
+ * \param barrier Defines the upper bound for the timeout.
* \param s Pointer to the scheduler struct.
*
- * \return If \a barrier is in the past, this function does nothing and returns
- * zero. Otherwise it returns one.
+ * \return If the barrier is in the past, this function does nothing and
+ * returns zero. Otherwise it returns one.
*
* \sa \ref sched_request_barrier_or_min_delay().
*/
}
/**
- * Force the next select() call to return before the given time.
+ * Bound the I/O timeout or request a minimal delay.
*
- * \param barrier Absolute time before select() should return.
+ * \param barrier Absolute time as in \ref sched_request_barrier().
* \param s Pointer to the scheduler struct.
*
- * \return If \a barrier is in the past, this function requests a minimal
+ * \return If the barrier is in the past, this function requests a minimal
* timeout and returns zero. Otherwise it returns one.
*
* \sa \ref sched_min_delay(), \ref sched_request_barrier().
return 1;
}
-static void sched_fd_set(int fd, fd_set *fds, int *max_fileno)
+static void add_pollfd(int fd, struct sched *s, short events)
{
- assert(fd >= 0 && fd < FD_SETSIZE);
+ assert(fd >= 0);
#if 0
{
int flags = fcntl(fd, F_GETFL);
}
}
#endif
- FD_SET(fd, fds);
- *max_fileno = PARA_MAX(*max_fileno, fd);
+ if (s->pidx_array_len > fd) { /* is fd already registered? */
+ if (s->pidx[fd] < s->pfd_array_len) { /* yes, it is */
+ assert(s->pfd[s->pidx[fd]].fd == fd);
+ s->pfd[s->pidx[fd]].events |= events;
+ return;
+ }
+ } else { /* need to extend the index array */
+ unsigned old_len = s->pidx_array_len;
+ while (s->pidx_array_len <= fd)
+ s->pidx_array_len = s->pidx_array_len * 2 + 1;
+ PARA_INFO_LOG("pidx array len: %u\n", s->pidx_array_len);
+ s->pidx = para_realloc(s->pidx,
+ s->pidx_array_len * sizeof(unsigned));
+ memset(s->pidx + old_len, 0xff,
+ (s->pidx_array_len - old_len) * sizeof(unsigned));
+ }
+ /*
+ * The given fd is not part of the pfd array yet. Initialize pidx[fd]
+ * to point at the next unused slot of this array and initialize the
+ * slot.
+ */
+ s->pidx[fd] = s->num_pfds;
+ if (s->pfd_array_len <= s->num_pfds) {
+ unsigned old_len = s->pfd_array_len;
+ s->pfd_array_len = old_len * 2 + 1;
+ PARA_INFO_LOG("pfd array len: %u\n", s->pfd_array_len);
+ s->pfd = para_realloc(s->pfd,
+ s->pfd_array_len * sizeof(struct pollfd));
+ memset(s->pfd + old_len, 0,
+ (s->pfd_array_len - old_len) * sizeof(struct pollfd));
+ }
+ s->pfd[s->num_pfds].fd = fd;
+ s->pfd[s->num_pfds].events = events;
+ s->pfd[s->num_pfds].revents = 0;
+ s->num_pfds++;
}
/**
*/
void sched_monitor_readfd(int fd, struct sched *s)
{
- sched_fd_set(fd, &s->rfds, &s->max_fileno);
+ add_pollfd(fd, s, POLLIN);
}
/**
*/
void sched_monitor_writefd(int fd, struct sched *s)
{
- sched_fd_set(fd, &s->wfds, &s->max_fileno);
+ add_pollfd(fd, s, POLLOUT);
+}
+
+static int get_revents(int fd, const struct sched *s)
+{
+ if (fd < 0)
+ return 0;
+ if (fd >= s->pidx_array_len)
+ return 0;
+ if (s->pidx[fd] >= s->num_pfds)
+ return 0;
+ if (s->pfd[s->pidx[fd]].fd != fd)
+ return 0;
+ assert((s->pfd[s->pidx[fd]].revents & POLLNVAL) == 0);
+ return s->pfd[s->pidx[fd]].revents;
+}
+
+/**
+ * Check whether there is data to read on the given fd.
+ *
+ * To be called from the ->post_monitor() method of a task.
+ *
+ * \param fd Should have been monitored with \ref sched_monitor_readfd().
+ * \param s The scheduler instance.
+ *
+ * \return True if the file descriptor is ready for reading, false otherwise.
+ * If fd is negative, or has not been monitored in the current iteration of the
+ * scheduler's main loop, the function also returns false.
+ *
+ * \sa \ref sched_write_ok().
+ */
+bool sched_read_ok(int fd, const struct sched *s)
+{
+ return get_revents(fd, s) & (POLLIN | POLLERR | POLLHUP);
+}
+
+/**
+ * Check whether writing is possible (i.e., does not block).
+ *
+ * \param fd Should have been monitored with \ref sched_monitor_writefd().
+ * \param s The scheduler instance.
+ *
+ * \return True if the file descriptor is ready for writing, false otherwise.
+ * The comment in \ref sched_read_ok() about invalid file descriptors applies
+ * to this function as well.
+ */
+bool sched_write_ok(int fd, const struct sched *s)
+{
+ return get_revents(fd, s) & (POLLOUT | POLLERR | POLLHUP);
}
* Designed with KISS in mind. It maintains a list of task structures which is
* extended when a new task is registered. Each task may define a pre_monitor
* function which is called from the scheduler main loop before it calls
- * select(). Similarly, each task must define a post_monitor function which is
- * called after the select call.
+ * poll(2). Similarly, each task must define a post_monitor function which is
+ * called after poll(2) returns.
*
* \sa select(2), poll(2).
*/
struct sched {
/** Initial value (in milliseconds) before any pre_monitor call. */
int default_timeout;
- /** The timeout (also in milliseconds) for the next select call. */
+ /** The timeout (also in milliseconds) for the next iteration. */
int timeout;
- /** fds that should be watched for readability. */
- fd_set rfds;
- /** fds that should be watched for writability. */
- fd_set wfds;
- /** Highest numbered file descriptor in any of the above fd sets. */
- int max_fileno;
- /** If non-NULL, use this function instead of para_select. */
- int (*select_function)(int, fd_set *, fd_set *, int timeout);
+ /** Passed to poll(2). */
+ struct pollfd *pfd;
+ /** Number of elements in the above array, passed to poll(2). */
+ unsigned pfd_array_len;
+ /** Number of fds registered for montitoring so far. */
+ unsigned num_pfds;
+ /** Maps fds to indices of the pfd array. */
+ unsigned *pidx;
+ /** Mumber of elements in the above pidx array. */
+ unsigned pidx_array_len;
+ /** If non-NULL, use this function instead of \ref xpoll(). */
+ int (*poll_function)(struct pollfd *fds, nfds_t nfds, int timeout);
/** Tasks which have been registered to the scheduler. */
struct list_head task_list;
};
int sched_request_barrier_or_min_delay(struct timeval *barrier, struct sched *s);
void sched_monitor_readfd(int fd, struct sched *s);
void sched_monitor_writefd(int fd, struct sched *s);
-
-static inline bool sched_read_ok(int fd, const struct sched *s)
-{
- return FD_ISSET(fd, &s->rfds);
-}
-
-static inline bool sched_write_ok(int fd, const struct sched *s)
-{
- return FD_ISSET(fd, &s->wfds);
-}
+bool sched_read_ok(int fd, const struct sched *s);
+bool sched_write_ok(int fd, const struct sched *s);
* schedule() to return as there are no more runnable tasks.
*
* Note that semaphores are not inherited across a fork(), so we don't
- * hold the lock at this point. Since server_select() drops the lock
- * prior to calling para_select(), we need to acquire it here.
+ * hold the lock at this point. Since server_poll() drops the lock
+ * prior to calling poll(), we need to acquire it here.
*/
mutex_lock(mmd_mutex);
return -E_CHILD_CONTEXT;
killpg(0, SIGUSR1);
}
-static int server_select(int max_fileno, fd_set *readfds, fd_set *writefds,
- int timeout)
+static int server_poll(struct pollfd *fds, nfds_t nfds, int timeout)
{
int ret;
status_refresh();
mutex_unlock(mmd_mutex);
- ret = para_select(max_fileno + 1, readfds, writefds, timeout);
+ ret = xpoll(fds, nfds, timeout);
mutex_lock(mmd_mutex);
return ret;
}
*sct = &server_command_task_struct;
sched.default_timeout = 1000;
- sched.select_function = server_select;
+ sched.poll_function = server_poll;
server_init(argc, argv, sct);
mutex_lock(mmd_mutex);
ret = schedule(&sched);
/*
- * We hold the mmd lock: it was re-acquired in server_select()
- * after the select call.
+ * We hold the mmd lock: it was re-acquired in server_poll()
+ * after the poll(2) call.
*/
mutex_unlock(mmd_mutex);
sched_shutdown(&sched);
#include <math.h>
#include <regex.h>
-#include <sys/select.h>
#include "para.h"
#include "error.h"
projects / paraslash.git / commitdiff