Port: Add Solaris support to socket compat

[lttng-tools.git] / src / common / compat / compat-epoll.c

diff --git a/src/common/compat/compat-epoll.c b/src/common/compat/compat-epoll.c
index 1380ce85527a74dae304b2777de5a72c489b6b5c..5d6153b64d075b5da4dc9881680be992e6018b6f 100644 (file)
--- a/src/common/compat/compat-epoll.c
+++ b/src/common/compat/compat-epoll.c
@@ -16,6 +16,7 @@
  */
 
 #define _GNU_SOURCE
+#define _LGPL_SOURCE
 #include <assert.h>
 #include <fcntl.h>
 #include <limits.h>
@@ -51,6 +52,11 @@ static int resize_poll_event(struct lttng_poll_event *events,
                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;
 
@@ -71,12 +77,17 @@ int compat_epoll_create(struct lttng_poll_event *events, int size, int flags)
                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");
@@ -119,6 +130,11 @@ int compat_epoll_add(struct lttng_poll_event *events, int fd, uint32_t req_event
                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;
 
@@ -155,7 +171,7 @@ int compat_epoll_del(struct lttng_poll_event *events, int fd)
 {
        int ret;
 
-       if (events == NULL || fd < 0) {
+       if (events == NULL || fd < 0 || events->nb_fd == 0) {
                goto error;
        }
 
@@ -194,6 +210,12 @@ int compat_epoll_wait(struct lttng_poll_event *events, int timeout)
                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
@@ -201,23 +223,8 @@ int compat_epoll_wait(struct lttng_poll_event *events, int timeout)
         * 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. */
@@ -247,17 +254,16 @@ error:
 /*
  * Setup poll set maximum size.
  */
-void compat_epoll_set_max_size(void)
+int compat_epoll_set_max_size(void)
 {
-       int ret, fd;
-       size_t size_ret;
+       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;
        }
 
        size_ret = lttng_read(fd, buf, sizeof(buf));
@@ -267,21 +273,20 @@ void compat_epoll_set_max_size(void)
         */
        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;
 }