diff options
Diffstat (limited to 'nscd')
-rw-r--r-- | nscd/nscd_helper.c | 72 |
1 files changed, 49 insertions, 23 deletions
diff --git a/nscd/nscd_helper.c b/nscd/nscd_helper.c index c99cb430aa..ed7c863aaf 100644 --- a/nscd/nscd_helper.c +++ b/nscd/nscd_helper.c @@ -26,6 +26,7 @@ #include <sys/poll.h> #include <sys/socket.h> #include <sys/stat.h> +#include <sys/time.h> #include <sys/uio.h> #include <sys/un.h> #include <not-cancel.h> @@ -135,6 +136,36 @@ __nscd_unmap (struct mapped_database *mapped) } +static int +wait_on_socket (int sock) +{ + struct pollfd fds[1]; + fds[0].fd = sock; + fds[0].events = POLLIN | POLLERR | POLLHUP; + int n = __poll (fds, 1, 5 * 1000); + if (n == -1 && __builtin_expect (errno == EINTR, 0)) + { + /* Handle the case where the poll() call is interrupted by a + signal. We cannot just use TEMP_FAILURE_RETRY since it might + lead to infinite loops. */ + struct timeval now; + (void) __gettimeofday (&now, NULL); + long int end = (now.tv_sec + 5) * 1000 + (now.tv_usec + 500) / 1000; + while (1) + { + long int timeout = end - (now.tv_sec * 1000 + + (now.tv_usec + 500) / 1000); + n = __poll (fds, 1, timeout); + if (n != -1 || errno != EINTR) + break; + (void) __gettimeofday (&now, NULL); + } + } + + return n; +} + + /* Try to get a file descriptor for the shared meory segment containing the database. */ static struct mapped_database * @@ -176,24 +207,27 @@ get_mapping (request_type type, const char *key, iov[0].iov_base = resdata; iov[0].iov_len = keylen; - char buf[CMSG_SPACE (sizeof (int))]; + union + { + struct cmsghdr hdr; + char bytes[CMSG_SPACE (sizeof (int))]; + } buf; struct msghdr msg = { .msg_iov = iov, .msg_iovlen = 1, - .msg_control = buf, .msg_controllen = sizeof (buf) }; + .msg_control = buf.bytes, + .msg_controllen = sizeof (buf) }; struct cmsghdr *cmsg = CMSG_FIRSTHDR (&msg); cmsg->cmsg_level = SOL_SOCKET; cmsg->cmsg_type = SCM_RIGHTS; cmsg->cmsg_len = CMSG_LEN (sizeof (int)); + /* This access is well-aligned since BUF is correctly aligned for an + int and CMSG_DATA preserves this alignment. */ *(int *) CMSG_DATA (cmsg) = -1; msg.msg_controllen = cmsg->cmsg_len; - struct pollfd fds[1]; - fds[0].fd = sock; - fds[0].events = POLLIN | POLLERR | POLLHUP; - if (__poll (fds, 1, 5 * 1000) <= 0) - /* Failure or timeout. */ + if (wait_on_socket (sock) <= 0) goto out_close2; #ifndef MSG_NOSIGNAL @@ -236,13 +270,11 @@ get_mapping (request_type type, const char *key, if (mapping != MAP_FAILED) { /* Allocate a record for the mapping. */ - struct mapped_database *newp; - - newp = malloc (sizeof (*newp)); + struct mapped_database *newp = malloc (sizeof (*newp)); if (newp == NULL) { /* Ugh, after all we went through the memory allocation failed. */ - __munmap (result, size); + __munmap (mapping, size); goto out_close; } @@ -372,19 +404,13 @@ __nscd_open_socket (const char *key, size_t keylen, request_type type, vec[1].iov_len = keylen; ssize_t nbytes = TEMP_FAILURE_RETRY (__writev (sock, vec, 2)); - if (nbytes == (ssize_t) (sizeof (request_header) + keylen)) - { + if (nbytes == (ssize_t) (sizeof (request_header) + keylen) /* Wait for data. */ - struct pollfd fds[1]; - fds[0].fd = sock; - fds[0].events = POLLIN | POLLERR | POLLHUP; - if (__poll (fds, 1, 5 * 1000) > 0) - { - nbytes = TEMP_FAILURE_RETRY (__read (sock, response, - responselen)); - if (nbytes == (ssize_t) responselen) - return sock; - } + && wait_on_socket (sock) > 0) + { + nbytes = TEMP_FAILURE_RETRY (__read (sock, response, responselen)); + if (nbytes == (ssize_t) responselen) + return sock; } close_not_cancel_no_status (sock); |