*/
#define _GNU_SOURCE
+#define _LGPL_SOURCE
#include <assert.h>
#include <fcntl.h>
#include <limits.h>
PERROR("realloc epoll add");
goto error;
}
+ if (new_size > events->alloc_size) {
+ /* Zero newly allocated memory */
+ memset(ptr + events->alloc_size, 0,
+ (new_size - events->alloc_size) * sizeof(*ptr));
+ }
events->events = ptr;
events->alloc_size = new_size;
goto error;
}
+ if (!poll_max_size) {
+ ERR("poll_max_size not initialized yet");
+ goto error;
+ }
+
/* Don't bust the limit here */
- if (size > poll_max_size && poll_max_size != 0) {
+ if (size > poll_max_size) {
size = poll_max_size;
}
- ret = epoll_create1(flags);
+ ret = compat_glibc_epoll_create(size, flags);
if (ret < 0) {
/* At this point, every error is fatal */
PERROR("epoll_create1");
goto error;
}
+ /*
+ * Zero struct epoll_event to ensure all representations of its
+ * union are zeroed.
+ */
+ memset(&ev, 0, sizeof(ev));
ev.events = req_events;
ev.data.fd = fd;
{
int ret;
- if (events == NULL || fd < 0) {
+ if (events == NULL || fd < 0 || events->nb_fd == 0) {
goto error;
}
ERR("Wrong arguments in compat_epoll_wait");
goto error;
}
+ assert(events->nb_fd >= 0);
+
+ if (events->nb_fd == 0) {
+ errno = EINVAL;
+ return -1;
+ }
/*
* Resize if needed before waiting. We could either expand the array or
* ensured that the events argument of the epoll_wait call will be large
* enough to hold every possible returned events.
*/
- if (events->nb_fd > events->alloc_size) {
- /* Expand if the nb_fd is higher than the actual size. */
- new_size = max_t(uint32_t,
- 1U << utils_get_count_order_u32(events->nb_fd),
- events->alloc_size << 1UL);
- } else if ((events->nb_fd << 1UL) <= events->alloc_size &&
- events->nb_fd >= events->init_size) {
- /* Shrink if nb_fd multiplied by two is <= than the actual size. */
- new_size = max_t(uint32_t,
- utils_get_count_order_u32(events->nb_fd) >> 1U,
- events->alloc_size >> 1U);
- } else {
- /* Indicate that we don't want to resize. */
- new_size = 0;
- }
-
- if (new_size) {
+ new_size = 1U << utils_get_count_order_u32(events->nb_fd);
+ if (new_size != events->alloc_size && new_size >= events->init_size) {
ret = resize_poll_event(events, new_size);
if (ret < 0) {
/* ENOMEM problem at this point. */
/*
* Setup poll set maximum size.
*/
-void compat_epoll_set_max_size(void)
+int compat_epoll_set_max_size(void)
{
- int ret, fd;
+ int ret, fd, retval = 0;
+ ssize_t size_ret;
char buf[64];
- poll_max_size = DEFAULT_POLL_SIZE;
-
fd = open(COMPAT_EPOLL_PROC_PATH, O_RDONLY);
if (fd < 0) {
- return;
+ retval = -1;
+ goto end;
}
- ret = read(fd, buf, sizeof(buf));
- if (ret < 0) {
+ size_ret = lttng_read(fd, buf, sizeof(buf));
+ /*
+ * Allow reading a file smaller than buf, but keep space for
+ * final \0.
+ */
+ if (size_ret < 0 || size_ret >= sizeof(buf)) {
PERROR("read set max size");
- goto error;
+ retval = -1;
+ goto end_read;
}
-
+ buf[size_ret] = '\0';
poll_max_size = atoi(buf);
- if (poll_max_size == 0) {
- /* Extra precaution */
- poll_max_size = DEFAULT_POLL_SIZE;
- }
-
- DBG("epoll set max size is %d", poll_max_size);
-
-error:
+end_read:
ret = close(fd);
if (ret) {
PERROR("close");
}
+end:
+ if (!poll_max_size) {
+ poll_max_size = DEFAULT_POLL_SIZE;
+ }
+ DBG("epoll set max size is %d", poll_max_size);
+ return retval;
}