/*
- * Copyright (C) 2011 - David Goulet <david.goulet@polymtl.ca>
+ * Copyright (C) 2011 David Goulet <david.goulet@polymtl.ca>
*
- * This program is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License, version 2 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: GPL-2.0-only
*
- * This program 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 General Public License for
- * more details.
- *
- * You should have received a copy of the GNU General Public License along
- * with this program; if not, write to the Free Software Foundation, Inc.,
- * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
#ifndef _LTT_POLL_H
#include <common/common.h>
-/*
- * Maximum number of fd we can monitor.
- *
- * For epoll(7), /proc/sys/fs/epoll/max_user_watches (since Linux 2.6.28) will
- * be used for the maximum size of the poll set. If this interface is not
- * available, according to the manpage, the max_user_watches value is 1/25 (4%)
- * of the available low memory divided by the registration cost in bytes which
- * is 90 bytes on a 32-bit kernel and 160 bytes on a 64-bit kernel.
- *
- * For poll(2), the max fds must not exceed RLIMIT_NOFILE given by
- * getrlimit(2).
- */
-extern unsigned int poll_max_size;
-
/*
* Used by lttng_poll_clean to free the events structure in a lttng_poll_event.
*/
#ifdef HAVE_EPOLL
#include <sys/epoll.h>
#include <stdio.h>
+#include <features.h>
+#include <common/compat/fcntl.h>
/* See man epoll(7) for this define path */
#define COMPAT_EPOLL_PROC_PATH "/proc/sys/fs/epoll/max_user_watches"
LPOLLNVAL = EPOLLHUP,
LPOLLRDHUP = EPOLLRDHUP,
/* Close on exec feature of epoll */
+#if defined(HAVE_EPOLL_CREATE1) && defined(EPOLL_CLOEXEC)
LTTNG_CLOEXEC = EPOLL_CLOEXEC,
+#else
+ /*
+ * EPOLL_CLOEXEC was added in glibc 2.8 (usually used in conjunction with
+ * epoll_create1(..)), but since neither EPOLL_CLOEXEC exists nor
+ * epoll_create1(..), we set it to FD_CLOEXEC so that we can pass it
+ * directly to fcntl(..) instead.
+ */
+ LTTNG_CLOEXEC = FD_CLOEXEC,
+#endif
};
struct compat_epoll_event {
#define LTTNG_POLL_GET_PREV_FD(e, i, nb_fd) \
__lttng_epoll_get_prev_fd(LTTNG_REF(e), i, nb_fd)
-/*
- * Create the epoll set. No memory allocation is done here.
- */
+/* Create the epoll set. */
extern int compat_epoll_create(struct lttng_poll_event *events,
int size, int flags);
#define lttng_poll_create(events, size, flags) \
compat_epoll_create(events, size, flags)
+#if defined(HAVE_EPOLL_CREATE1) && defined(EPOLL_CLOEXEC)
+static inline int compat_glibc_epoll_create(int size __attribute__((unused)),
+ int flags)
+{
+ return epoll_create1(flags);
+}
+#else
+static inline int compat_glibc_epoll_create(int size, int flags)
+{
+ /*
+ * epoll_create1 was added in glibc 2.9, but unfortunatly reverting to
+ * epoll_create(..) also means that we lose the possibility to
+ * directly set the EPOLL_CLOEXEC, so try and do it anyway but through
+ * fcntl(..).
+ */
+ int efd = epoll_create(size);
+ assert(fcntl(efd, F_SETFD, flags) != -1);
+ return efd;
+}
+#endif
+
/*
* Wait on epoll set with the number of fd registered to the lttng_poll_event
* data structure (events).
*/
-extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout);
+extern int compat_epoll_wait(struct lttng_poll_event *events, int timeout,
+ bool interruptible);
#define lttng_poll_wait(events, timeout) \
- compat_epoll_wait(events, timeout)
+ compat_epoll_wait(events, timeout, false)
+#define lttng_poll_wait_interruptible(events, timeout) \
+ compat_epoll_wait(events, timeout, true)
/*
* Add a fd to the epoll set and resize the epoll_event structure if needed.
#define lttng_poll_del(events, fd) \
compat_epoll_del(events, fd)
+/*
+ * Modify an fd's events in the epoll set.
+ */
+extern int compat_epoll_mod(struct lttng_poll_event *events,
+ int fd, uint32_t req_events);
+#define lttng_poll_mod(events, fd, req_events) \
+ compat_epoll_mod(events, fd, req_events)
+
/*
* Set up the poll set limits variable poll_max_size
*/
-extern void compat_epoll_set_max_size(void);
+extern int compat_epoll_set_max_size(void);
#define lttng_poll_set_max_size() \
compat_epoll_set_max_size()
}
}
+/*
+ * Initialize an already allocated poll event data structure. For epoll(), the
+ * epfd is set to -1 to indicate that it's not usable.
+ */
+static inline void lttng_poll_init(struct lttng_poll_event *events)
+{
+ memset(events, 0, sizeof(struct lttng_poll_event));
+ /* Set fd to -1 so if clean before created, we don't close 0. */
+ events->epfd = -1;
+}
+
/*
* Clean the events structure of a lttng_poll_event. It's the caller
* responsability to free the lttng_poll_event memory.
if (events->epfd >= 0) {
ret = close(events->epfd);
if (ret) {
- perror("close");
+ PERROR("close");
}
}
#if __linux__
LPOLLMSG = POLLMSG,
LPOLLRDHUP = POLLRDHUP,
-#elif (defined(__FreeBSD__) || defined(__CYGWIN__))
+#elif (defined(__FreeBSD__) || defined(__CYGWIN__) || defined(__sun__) || defined(__APPLE__))
LPOLLMSG = 0,
LPOLLRDHUP = 0,
#else
* execution before a poll wait is done.
*/
struct compat_poll_event_array current;
- /* Indicate if wait.events needs to be realloc. */
- int need_realloc:1;
+
/* Indicate if wait.events need to be updated from current. */
int need_update:1;
};
/*
* For the following calls, consider 'e' to be a lttng_poll_event pointer and i
* being the index of the events array.
+ * LTTNG_POLL_GETNB is always used after lttng_poll_wait, thus we can use the
+ * current list for test compatibility purposes.
*/
#define LTTNG_POLL_GETFD(e, i) LTTNG_REF(e)->wait.events[i].fd
#define LTTNG_POLL_GETEV(e, i) LTTNG_REF(e)->wait.events[i].revents
-#define LTTNG_POLL_GETNB(e) LTTNG_REF(e)->wait.nb_fd
+#define LTTNG_POLL_GETNB(e) LTTNG_REF(e)->current.nb_fd
#define LTTNG_POLL_GETSZ(e) LTTNG_REF(e)->wait.events_size
#define LTTNG_POLL_GET_PREV_FD(e, i, nb_fd) \
__lttng_poll_get_prev_fd(LTTNG_REF(e), i, nb_fd)
* Wait on poll(2) event with nb_fd registered to the lttng_poll_event data
* structure.
*/
-extern int compat_poll_wait(struct lttng_poll_event *events, int timeout);
+extern int compat_poll_wait(struct lttng_poll_event *events, int timeout,
+ bool interruptible);
#define lttng_poll_wait(events, timeout) \
- compat_poll_wait(events, timeout)
+ compat_poll_wait(events, timeout, false)
+#define lttng_poll_wait_interruptible(events, timeout) \
+ compat_poll_wait(events, timeout, true)
/*
* Add the fd to the pollfd structure. Resize if needed.
#define lttng_poll_del(events, fd) \
compat_poll_del(events, fd)
+/*
+ * Modify an fd's events in the poll set.
+ */
+extern int compat_poll_mod(struct lttng_poll_event *events,
+ int fd, uint32_t req_events);
+#define lttng_poll_mod(events, fd, req_events) \
+ compat_poll_mod(events, fd, req_events)
+
/*
* Set up the poll set limits variable poll_max_size
*/
-extern void compat_poll_set_max_size(void);
+extern int compat_poll_set_max_size(void);
#define lttng_poll_set_max_size() \
compat_poll_set_max_size()
static inline void lttng_poll_reset(struct lttng_poll_event *events)
{}
+/*
+ * Initialize an already allocated poll event data structure.
+ */
+static inline void lttng_poll_init(struct lttng_poll_event *events)
+{
+ memset(events, 0, sizeof(struct lttng_poll_event));
+}
+
/*
* Clean the events structure of a lttng_poll_event. It's the caller
* responsability to free the lttng_poll_event memory.