diff options
Diffstat (limited to 'erts/emulator/sys/unix/sys_uds.c')
-rw-r--r-- | erts/emulator/sys/unix/sys_uds.c | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/erts/emulator/sys/unix/sys_uds.c b/erts/emulator/sys/unix/sys_uds.c new file mode 100644 index 0000000000..015d0346a1 --- /dev/null +++ b/erts/emulator/sys/unix/sys_uds.c @@ -0,0 +1,155 @@ +/* + * %CopyrightBegin% + * + * Copyright Ericsson AB 2002-2009. All Rights Reserved. + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + * %CopyrightEnd% + */ + +#include "sys_uds.h" + +int +sys_uds_readv(int fd, struct iovec *iov, size_t iov_len, + int *fds, int fd_count, int flags) { + struct msghdr msg; + struct cmsghdr *cmsg = NULL; + char ancillary_buff[256] = {0}; + int res, i = 0; + + /* setup a place to fill in message contents */ + memset(&msg, 0, sizeof(struct msghdr)); + msg.msg_iov = iov; + msg.msg_iovlen = iov_len; + + /* provide space for the ancillary data */ + msg.msg_control = ancillary_buff; + msg.msg_controllen = sizeof(ancillary_buff); + + if((res = recvmsg(fd, &msg, flags)) < 0) { +#if defined(__APPLE__) && defined(__MACH__) && !defined(__DARWIN__) + /* When some OS X versions run out of fd's + they give EMSGSIZE instead of EMFILE. + We remap this as we want the correct + error to appear for the user */ + if (errno == EMSGSIZE) + errno = EMFILE; +#endif + return res; + } + + if((msg.msg_flags & MSG_CTRUNC) == MSG_CTRUNC) + { + /* We assume that we have given enough space for any header + that are sent to us. So the only remaining reason to get + this flag set is if the caller has run out of file descriptors. + */ + errno = EMFILE; + return -1; + } + + for (cmsg = CMSG_FIRSTHDR(&msg); cmsg; cmsg = CMSG_NXTHDR(&msg, cmsg) ) { + if ((cmsg->cmsg_level == SOL_SOCKET) && + (cmsg->cmsg_type == SCM_RIGHTS)) { + int *cmsg_data = (int *)CMSG_DATA(cmsg); + while ((char*)cmsg_data < (char*)cmsg + cmsg->cmsg_len) { + if (i < fd_count) { + fds[i++] = *cmsg_data++; + } else { + /* for some strange reason, we have received more FD's + than we wanted... close them if we are not running + debug. */ + if(i >= fd_count) abort(); + close(*cmsg_data++); + } + } + } + } + + return res; +} + +int +sys_uds_read(int fd, char *buff, size_t len, + int *fds, int fd_count, int flags) { + struct iovec iov; + iov.iov_base = buff; + iov.iov_len = len; + return sys_uds_readv(fd, &iov, 1, fds, fd_count, flags); +} + + +int +sys_uds_writev(int fd, struct iovec *iov, size_t iov_len, + int *fds, int fd_count, int flags) { + + struct msghdr msg; + struct cmsghdr *cmsg = NULL; + int res, i; + + /* initialize socket message */ + memset(&msg, 0, sizeof(struct msghdr)); + + /* We flatten the iov if it is too long */ + if (iov_len > MAXIOV) { + int size = 0; + char *buff; + for (i = 0; i < iov_len; i++) + size += iov[i].iov_len; + buff = malloc(size); + + for (i = 0; i < iov_len; i++) { + memcpy(buff, iov[i].iov_base, iov[i].iov_len); + buff += iov[i].iov_len; + } + + iov[0].iov_base = buff - size; + iov[0].iov_len = size; + msg.msg_iov = iov; + msg.msg_iovlen = 1; + } else { + msg.msg_iov = iov; + msg.msg_iovlen = iov_len; + } + + /* initialize the ancillary data */ + msg.msg_control = calloc(1, CMSG_SPACE(sizeof(int) * fd_count)); + msg.msg_controllen = CMSG_SPACE(sizeof(int) * fd_count); + + /* copy the fd array into the ancillary data */ + cmsg = CMSG_FIRSTHDR(&msg); + if(!cmsg) abort(); + cmsg->cmsg_level = SOL_SOCKET; + cmsg->cmsg_type = SCM_RIGHTS; + cmsg->cmsg_len = CMSG_LEN(sizeof(int) * fd_count); + memcpy(CMSG_DATA(cmsg), fds, sizeof(int) * fd_count); + + res = sendmsg(fd, &msg, flags); + + if (iov_len > MAXIOV) + free(iov[0].iov_base); + + free(msg.msg_control); + + return res; +} + +int +sys_uds_write(int fd, char *buff, size_t len, + int *fds, int fd_count, int flags) { + struct iovec iov; + iov.iov_base = buff; + iov.iov_len = len; + return sys_uds_writev(fd, &iov, 1, fds, fd_count, flags); +} |