| /* |
| * New osmocom async I/O API. |
| * |
| * (C) 2022-2024 by Harald Welte <laforge@osmocom.org> |
| * (C) 2022-2024 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de> |
| * Author: Daniel Willmann <dwillmann@sysmocom.de> |
| * |
| * All Rights Reserved. |
| * |
| * SPDX-License-Identifier: GPL-2.0+ |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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. |
| */ |
| |
| #include "../config.h" |
| #ifndef EMBEDDED |
| |
| #include <fcntl.h> |
| #include <stdio.h> |
| #include <stdlib.h> |
| #include <talloc.h> |
| #include <unistd.h> |
| #include <string.h> |
| #include <stdbool.h> |
| #include <errno.h> |
| |
| #include <osmocom/core/osmo_io.h> |
| #include <osmocom/core/linuxlist.h> |
| #include <osmocom/core/logging.h> |
| #include <osmocom/core/msgb.h> |
| #include <osmocom/core/socket.h> |
| #include <osmocom/core/talloc.h> |
| #include <osmocom/core/utils.h> |
| |
| #include "osmo_io_internal.h" |
| |
| /*! \addtogroup osmo_io |
| * @{ |
| * |
| * \file osmo_io.c */ |
| |
| /*! This environment variable can be set to manually set the backend used in osmo_io */ |
| #define OSMO_IO_BACKEND_ENV "LIBOSMO_IO_BACKEND" |
| |
| const struct value_string osmo_io_backend_names[] = { |
| { OSMO_IO_BACKEND_POLL, "poll" }, |
| { OSMO_IO_BACKEND_IO_URING, "io_uring" }, |
| { 0, NULL } |
| }; |
| |
| const struct value_string osmo_iofd_mode_names[] = { |
| { OSMO_IO_FD_MODE_READ_WRITE, "read/write" }, |
| { OSMO_IO_FD_MODE_RECVFROM_SENDTO, "recvfrom/sendto" }, |
| { OSMO_IO_FD_MODE_RECVMSG_SENDMSG, "recvmsg/sendmsg" }, |
| { 0, NULL } |
| }; |
| |
| static enum osmo_io_backend g_io_backend; |
| |
| /* Used by some tests, can't be static */ |
| struct iofd_backend_ops osmo_iofd_ops; |
| |
| #if defined(HAVE_URING) |
| void osmo_iofd_uring_init(void); |
| #endif |
| |
| /*! initialize osmo_io for the current thread */ |
| void osmo_iofd_init(void) |
| { |
| switch (g_io_backend) { |
| case OSMO_IO_BACKEND_POLL: |
| break; |
| #if defined(HAVE_URING) |
| case OSMO_IO_BACKEND_IO_URING: |
| osmo_iofd_uring_init(); |
| break; |
| #endif |
| default: |
| OSMO_ASSERT(0); |
| break; |
| } |
| } |
| |
| /* ensure main thread always has pre-initialized osmo_io |
| * priority 103: run after on_dso_load_select */ |
| static __attribute__((constructor(103))) void on_dso_load_osmo_io(void) |
| { |
| char *backend = getenv(OSMO_IO_BACKEND_ENV); |
| if (backend == NULL) |
| backend = OSMO_IO_BACKEND_DEFAULT; |
| |
| if (!strcmp("POLL", backend)) { |
| g_io_backend = OSMO_IO_BACKEND_POLL; |
| osmo_iofd_ops = iofd_poll_ops; |
| #if defined(HAVE_URING) |
| } else if (!strcmp("IO_URING", backend)) { |
| g_io_backend = OSMO_IO_BACKEND_IO_URING; |
| osmo_iofd_ops = iofd_uring_ops; |
| #endif |
| } else { |
| fprintf(stderr, "Invalid osmo_io backend requested: \"%s\"\nCheck the environment variable %s\n", backend, OSMO_IO_BACKEND_ENV); |
| exit(1); |
| } |
| |
| OSMO_ASSERT(osmo_iofd_ops.close); |
| OSMO_ASSERT(osmo_iofd_ops.register_fd); |
| OSMO_ASSERT(osmo_iofd_ops.unregister_fd); |
| OSMO_ASSERT(osmo_iofd_ops.write_enable); |
| OSMO_ASSERT(osmo_iofd_ops.write_disable); |
| OSMO_ASSERT(osmo_iofd_ops.read_enable); |
| OSMO_ASSERT(osmo_iofd_ops.read_disable); |
| OSMO_ASSERT(osmo_iofd_ops.notify_connected); |
| |
| osmo_iofd_init(); |
| } |
| |
| /*! Allocate the msghdr. |
| * \param[in] iofd the osmo_io file structure |
| * \param[in] action the action this msg(hdr) is for (read, write, ..) |
| * \param[in] msg the msg buffer to use. Will allocate a new one if NULL |
| * \param[in] cmsg_size size (in bytes) of iofd_msghdr.cmsg buffer. Can be 0 if cmsg is not used. |
| * \returns the newly allocated msghdr or NULL in case of error */ |
| struct iofd_msghdr *iofd_msghdr_alloc(struct osmo_io_fd *iofd, enum iofd_msg_action action, struct msgb *msg, |
| size_t cmsg_size) |
| { |
| bool free_msg = false; |
| struct iofd_msghdr *hdr; |
| |
| if (!msg) { |
| msg = iofd_msgb_alloc(iofd); |
| if (!msg) |
| return NULL; |
| free_msg = true; |
| } else { |
| talloc_steal(iofd, msg); |
| } |
| |
| hdr = talloc_zero_size(iofd, sizeof(struct iofd_msghdr) + cmsg_size); |
| if (!hdr) { |
| if (free_msg) |
| talloc_free(msg); |
| return NULL; |
| } |
| |
| hdr->action = action; |
| hdr->iofd = iofd; |
| hdr->msg = msg; |
| |
| return hdr; |
| } |
| |
| /*! Free the msghdr. |
| * \param[in] msghdr the msghdr to free |
| */ |
| void iofd_msghdr_free(struct iofd_msghdr *msghdr) |
| { |
| /* msghdr->msg is never owned by msghdr, it will either be freed in the send path or |
| * or passed on to the read callback which takes ownership. */ |
| talloc_free(msghdr); |
| } |
| |
| /*! convenience wrapper to call msgb_alloc with parameters from osmo_io_fd */ |
| struct msgb *iofd_msgb_alloc(struct osmo_io_fd *iofd) |
| { |
| uint16_t headroom = iofd->msgb_alloc.headroom; |
| |
| OSMO_ASSERT(iofd->msgb_alloc.size < 0xffff - headroom); |
| return msgb_alloc_headroom_c(iofd, iofd->msgb_alloc.size + headroom, headroom, "osmo_io_msgb"); |
| } |
| |
| /*! return the pending msgb in iofd or NULL if there is none*/ |
| struct msgb *iofd_msgb_pending(struct osmo_io_fd *iofd) |
| { |
| struct msgb *msg = NULL; |
| |
| msg = iofd->pending; |
| iofd->pending = NULL; |
| |
| return msg; |
| } |
| |
| /*! Return the pending msgb or allocate and return a new one */ |
| struct msgb *iofd_msgb_pending_or_alloc(struct osmo_io_fd *iofd) |
| { |
| struct msgb *msg = NULL; |
| |
| msg = iofd_msgb_pending(iofd); |
| if (!msg) |
| msg = iofd_msgb_alloc(iofd); |
| |
| return msg; |
| } |
| |
| /*! Enqueue a message to be sent. |
| * |
| * Enqueues the message at the back of the queue provided there is enough space. |
| * \param[in] iofd the file descriptor |
| * \param[in] msghdr the message to enqueue |
| * \returns 0 if the message was enqueued succcessfully, |
| * -ENOSPC if the queue already contains the maximum number of messages |
| */ |
| int iofd_txqueue_enqueue(struct osmo_io_fd *iofd, struct iofd_msghdr *msghdr) |
| { |
| if (iofd->tx_queue.current_length >= iofd->tx_queue.max_length) |
| return -ENOSPC; |
| |
| llist_add_tail(&msghdr->list, &iofd->tx_queue.msg_queue); |
| iofd->tx_queue.current_length++; |
| |
| if (iofd->tx_queue.current_length == 1 && !IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
| osmo_iofd_ops.write_enable(iofd); |
| |
| return 0; |
| } |
| |
| /*! Enqueue a message at the front. |
| * |
| * Used to enqueue a msgb from a partial send again. This function will always |
| * enqueue the message, even if the maximum number of messages is reached. |
| * \param[in] iofd the file descriptor |
| * \param[in] msghdr the message to enqueue |
| */ |
| void iofd_txqueue_enqueue_front(struct osmo_io_fd *iofd, struct iofd_msghdr *msghdr) |
| { |
| llist_add(&msghdr->list, &iofd->tx_queue.msg_queue); |
| iofd->tx_queue.current_length++; |
| |
| if (iofd->tx_queue.current_length == 1 && !IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
| osmo_iofd_ops.write_enable(iofd); |
| } |
| |
| /*! Dequeue a message from the front. |
| * |
| * \param[in] iofd the file descriptor |
| * \returns the msghdr from the front of the queue or NULL if the queue is empty |
| */ |
| struct iofd_msghdr *iofd_txqueue_dequeue(struct osmo_io_fd *iofd) |
| { |
| struct llist_head *lh; |
| |
| if (iofd->tx_queue.current_length == 0) |
| return NULL; |
| |
| lh = iofd->tx_queue.msg_queue.next; |
| |
| OSMO_ASSERT(lh); |
| iofd->tx_queue.current_length--; |
| llist_del(lh); |
| |
| if (iofd->tx_queue.current_length == 0) |
| osmo_iofd_ops.write_disable(iofd); |
| |
| return llist_entry(lh, struct iofd_msghdr, list); |
| } |
| |
| /*! Handle segmentation of the msg. If this function returns *_HANDLE_ONE or MORE then the data in msg will contain |
| * one complete message. |
| * If there are bytes left over, *pending_out will point to a msgb with the remaining data. |
| */ |
| static enum iofd_seg_act iofd_handle_segmentation(struct osmo_io_fd *iofd, struct msgb *msg, struct msgb **pending_out) |
| { |
| int extra_len, received_len, expected_len; |
| struct msgb *msg_pending; |
| |
| /* Save the start of message before segmentation_cb (which could change it) */ |
| uint8_t *data = msg->data; |
| |
| received_len = msgb_length(msg); |
| |
| if (iofd->io_ops.segmentation_cb2) { |
| expected_len = iofd->io_ops.segmentation_cb2(iofd, msg); |
| } else if (iofd->io_ops.segmentation_cb) { |
| expected_len = iofd->io_ops.segmentation_cb(msg); |
| } else { |
| *pending_out = NULL; |
| return IOFD_SEG_ACT_HANDLE_ONE; |
| } |
| |
| if (expected_len == -EAGAIN) { |
| goto defer; |
| } else if (expected_len < 0) { |
| /* Something is wrong, skip this msgb */ |
| LOGPIO(iofd, LOGL_ERROR, "segmentation_cb returned error (%d), skipping msg of size %d\n", |
| expected_len, received_len); |
| *pending_out = NULL; |
| msgb_free(msg); |
| return IOFD_SEG_ACT_DEFER; |
| } |
| |
| extra_len = received_len - expected_len; |
| /* No segmentation needed, return the whole msgb */ |
| if (extra_len == 0) { |
| *pending_out = NULL; |
| return IOFD_SEG_ACT_HANDLE_ONE; |
| /* segment is incomplete */ |
| } else if (extra_len < 0) { |
| goto defer; |
| } |
| |
| /* msgb contains more than one segment */ |
| /* Copy the trailing data over */ |
| msg_pending = iofd_msgb_alloc(iofd); |
| memcpy(msgb_data(msg_pending), data + expected_len, extra_len); |
| msgb_put(msg_pending, extra_len); |
| *pending_out = msg_pending; |
| |
| /* Trim the original msgb to size. Don't use msgb_trim because we need to reference |
| * msg->data from before it might have been modified by the segmentation_cb(). */ |
| msg->tail = data + expected_len; |
| msg->len = msg->tail - msg->data; |
| return IOFD_SEG_ACT_HANDLE_MORE; |
| |
| defer: |
| *pending_out = msg; |
| return IOFD_SEG_ACT_DEFER; |
| } |
| |
| /*! Restore message boundaries on read() and pass individual messages to the read callback |
| */ |
| void iofd_handle_segmented_read(struct osmo_io_fd *iofd, struct msgb *msg, int rc) |
| { |
| int res; |
| struct msgb *pending = NULL; |
| |
| OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_READ_WRITE); |
| |
| if (rc <= 0) { |
| iofd->io_ops.read_cb(iofd, rc, msg); |
| return; |
| } |
| |
| do { |
| res = iofd_handle_segmentation(iofd, msg, &pending); |
| if (res != IOFD_SEG_ACT_DEFER || rc < 0) |
| iofd->io_ops.read_cb(iofd, rc, msg); |
| if (res == IOFD_SEG_ACT_HANDLE_MORE) |
| msg = pending; |
| } while (res == IOFD_SEG_ACT_HANDLE_MORE); |
| |
| OSMO_ASSERT(iofd->pending == NULL); |
| iofd->pending = pending; |
| } |
| |
| /*! completion handler: Internal function called by osmo_io_backend after a given I/O operation has completed |
| * \param[in] iofd I/O file-descriptor on which I/O has completed |
| * \param[in] msg message buffer containing data related to completed I/O |
| * \param[in] rc result code with read size or error (-errno) |
| * \param[in] hdr serialized msghdr containing state of completed I/O */ |
| void iofd_handle_recv(struct osmo_io_fd *iofd, struct msgb *msg, int rc, struct iofd_msghdr *hdr) |
| { |
| talloc_steal(iofd->msgb_alloc.ctx, msg); |
| switch (iofd->mode) { |
| case OSMO_IO_FD_MODE_READ_WRITE: |
| iofd_handle_segmented_read(iofd, msg, rc); |
| break; |
| case OSMO_IO_FD_MODE_RECVFROM_SENDTO: |
| iofd->io_ops.recvfrom_cb(iofd, rc, msg, &hdr->osa); |
| break; |
| case OSMO_IO_FD_MODE_RECVMSG_SENDMSG: |
| iofd->io_ops.recvmsg_cb(iofd, rc, msg, &hdr->hdr); |
| break; |
| default: |
| OSMO_ASSERT(false); |
| break; |
| } |
| } |
| |
| /*! completion handler: Internal function called by osmo_io_backend after a given I/O operation has completed |
| * \param[in] iofd I/O file-descriptor on which I/O has completed |
| * \param[in] rc return value of the I/O operation |
| * \param[in] msghdr serialized msghdr containing state of completed I/O |
| */ |
| void iofd_handle_send_completion(struct osmo_io_fd *iofd, int rc, struct iofd_msghdr *msghdr) |
| { |
| struct msgb *msg = msghdr->msg; |
| |
| /* Incomplete write */ |
| if (rc > 0 && rc < msgb_length(msg)) { |
| /* Re-enqueue remaining data */ |
| msgb_pull(msg, rc); |
| msghdr->iov[0].iov_len = msgb_length(msg); |
| iofd_txqueue_enqueue_front(iofd, msghdr); |
| return; |
| } |
| |
| /* Reenqueue the complete msgb */ |
| if (rc == -EAGAIN) { |
| iofd_txqueue_enqueue_front(iofd, msghdr); |
| return; |
| } |
| |
| /* All other failure and success cases are handled here */ |
| switch (msghdr->action) { |
| case IOFD_ACT_WRITE: |
| if (iofd->io_ops.write_cb) |
| iofd->io_ops.write_cb(iofd, rc, msg); |
| break; |
| case IOFD_ACT_SENDTO: |
| if (iofd->io_ops.sendto_cb) |
| iofd->io_ops.sendto_cb(iofd, rc, msg, &msghdr->osa); |
| break; |
| case IOFD_ACT_SENDMSG: |
| if (iofd->io_ops.sendmsg_cb) |
| iofd->io_ops.sendmsg_cb(iofd, rc, msg); |
| break; |
| default: |
| OSMO_ASSERT(0); |
| } |
| |
| msgb_free(msghdr->msg); |
| iofd_msghdr_free(msghdr); |
| } |
| |
| /* Public functions */ |
| |
| /*! Write a message to a file descriptor / connected socket. |
| * The osmo_io_fd must be using OSMO_IO_FD_MODE_READ_WRITE. |
| * |
| * Appends the message to the internal transmit queue for eventual non-blocking |
| * write to the underlying socket/file descriptor. |
| * |
| * If the function returns success (0) it will take ownership of the msgb and |
| * internally call msgb_free() after the write request completes. |
| * In case of an error, the msgb needs to be freed by the caller. |
| * |
| * \param[in] iofd osmo_io_fd file descriptor to write data to |
| * \param[in] msg message buffer containing the data to write |
| * \returns 0 in case of success; a negative value in case of error |
| */ |
| int osmo_iofd_write_msgb(struct osmo_io_fd *iofd, struct msgb *msg) |
| { |
| int rc; |
| |
| if (OSMO_UNLIKELY(msgb_length(msg) == 0)) { |
| LOGPIO(iofd, LOGL_ERROR, "Length is 0, rejecting msgb.\n"); |
| return -EINVAL; |
| } |
| |
| OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_READ_WRITE); |
| |
| struct iofd_msghdr *msghdr = iofd_msghdr_alloc(iofd, IOFD_ACT_WRITE, msg, 0); |
| if (!msghdr) |
| return -ENOMEM; |
| |
| msghdr->flags = MSG_NOSIGNAL; |
| msghdr->iov[0].iov_base = msgb_data(msghdr->msg); |
| msghdr->iov[0].iov_len = msgb_length(msghdr->msg); |
| msghdr->hdr.msg_iov = &msghdr->iov[0]; |
| msghdr->hdr.msg_iovlen = 1; |
| |
| rc = iofd_txqueue_enqueue(iofd, msghdr); |
| if (rc < 0) { |
| iofd_msghdr_free(msghdr); |
| LOGPIO(iofd, LOGL_ERROR, "enqueueing message failed (%d). Rejecting msgb\n", rc); |
| return rc; |
| } |
| |
| return 0; |
| } |
| |
| /*! Send a message through an unconnected socket. |
| * The osmo_io_fd must be using OSMO_IO_FD_MODE_RECVFROM_SENDTO. |
| * |
| * Appends the message to the internal transmit queue for eventual non-blocking |
| * sendto on the underlying socket/file descriptor. |
| * |
| * If the function returns success (0), it will take ownership of the msgb and |
| * internally call msgb_free() after the sendto request completes. |
| * In case of an error the msgb needs to be freed by the caller. |
| * |
| * \param[in] iofd file descriptor to write to |
| * \param[in] msg message buffer to send |
| * \param[in] sendto_flags Flags to pass to the send call |
| * \param[in] dest destination address to send the message to |
| * \returns 0 in case of success; a negative value in case of error |
| */ |
| int osmo_iofd_sendto_msgb(struct osmo_io_fd *iofd, struct msgb *msg, int sendto_flags, const struct osmo_sockaddr *dest) |
| { |
| int rc; |
| |
| if (OSMO_UNLIKELY(msgb_length(msg) == 0)) { |
| LOGPIO(iofd, LOGL_ERROR, "Length is 0, rejecting msgb.\n"); |
| return -EINVAL; |
| } |
| |
| OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_RECVFROM_SENDTO); |
| |
| struct iofd_msghdr *msghdr = iofd_msghdr_alloc(iofd, IOFD_ACT_SENDTO, msg, 0); |
| if (!msghdr) |
| return -ENOMEM; |
| |
| if (dest) { |
| msghdr->osa = *dest; |
| msghdr->hdr.msg_name = &msghdr->osa.u.sa; |
| msghdr->hdr.msg_namelen = osmo_sockaddr_size(&msghdr->osa); |
| } |
| msghdr->flags = sendto_flags; |
| msghdr->iov[0].iov_base = msgb_data(msghdr->msg); |
| msghdr->iov[0].iov_len = msgb_length(msghdr->msg); |
| msghdr->hdr.msg_iov = &msghdr->iov[0]; |
| msghdr->hdr.msg_iovlen = 1; |
| |
| rc = iofd_txqueue_enqueue(iofd, msghdr); |
| if (rc < 0) { |
| iofd_msghdr_free(msghdr); |
| LOGPIO(iofd, LOGL_ERROR, "enqueueing message failed (%d). Rejecting msgb\n", rc); |
| return rc; |
| } |
| |
| return 0; |
| } |
| |
| /*! osmo_io equivalent of the sendmsg(2) socket API call. |
| * The osmo_io_fd must be using OSMO_IO_FD_MODE_RECVMSG_SENDMSG. |
| * |
| * Appends the message to the internal transmit queue for eventual non-blocking |
| * sendmsg on the underlying socket/file descriptor. |
| * |
| * If the function returns success (0), it will take ownership of the msgb and |
| * internally call msgb_free() after the sendmsg request completes. |
| * In case of an error the msgb needs to be freed by the caller. |
| * |
| * \param[in] iofd file descriptor to write to |
| * \param[in] msg message buffer to send; is used to fill msgh->iov[] |
| * \param[in] sendmsg_flags Flags to pass to the send call |
| * \param[in] msgh 'struct msghdr' for name/control/flags. iov must be empty! |
| * \returns 0 in case of success; a negative value in case of error |
| */ |
| int osmo_iofd_sendmsg_msgb(struct osmo_io_fd *iofd, struct msgb *msg, int sendmsg_flags, const struct msghdr *msgh) |
| { |
| int rc; |
| struct iofd_msghdr *msghdr; |
| |
| if (OSMO_UNLIKELY(msgb_length(msg) == 0)) { |
| LOGPIO(iofd, LOGL_ERROR, "Length is 0, rejecting msgb.\n"); |
| return -EINVAL; |
| } |
| |
| OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_RECVMSG_SENDMSG); |
| |
| if (OSMO_UNLIKELY(msgh->msg_namelen > sizeof(msghdr->osa))) { |
| LOGPIO(iofd, LOGL_ERROR, "osmo_iofd_sendmsg msg_namelen (%u) > supported %zu bytes\n", |
| msgh->msg_namelen, sizeof(msghdr->osa)); |
| return -EINVAL; |
| } |
| |
| if (OSMO_UNLIKELY(msgh->msg_iovlen)) { |
| LOGPIO(iofd, LOGL_ERROR, "osmo_iofd_sendmsg must have all in 'struct msgb', not in 'msg_iov'\n"); |
| return -EINVAL; |
| } |
| |
| msghdr = iofd_msghdr_alloc(iofd, IOFD_ACT_SENDMSG, msg, msgh->msg_controllen); |
| if (!msghdr) |
| return -ENOMEM; |
| |
| /* copy over optional address */ |
| if (msgh->msg_name) { |
| memcpy(&msghdr->osa, msgh->msg_name, msgh->msg_namelen); |
| msghdr->hdr.msg_name = &msghdr->osa.u.sa; |
| msghdr->hdr.msg_namelen = msgh->msg_namelen; |
| } |
| |
| /* build iov from msgb */ |
| msghdr->iov[0].iov_base = msgb_data(msghdr->msg); |
| msghdr->iov[0].iov_len = msgb_length(msghdr->msg); |
| msghdr->hdr.msg_iov = &msghdr->iov[0]; |
| msghdr->hdr.msg_iovlen = 1; |
| |
| /* copy over the cmsg from the msghdr */ |
| if (msgh->msg_control && msgh->msg_controllen) { |
| msghdr->hdr.msg_control = msghdr->cmsg; |
| msghdr->hdr.msg_controllen = msgh->msg_controllen; |
| memcpy(msghdr->cmsg, msgh->msg_control, msgh->msg_controllen); |
| } |
| |
| /* copy over msg_flags */ |
| msghdr->hdr.msg_flags = sendmsg_flags; |
| |
| rc = iofd_txqueue_enqueue(iofd, msghdr); |
| if (rc < 0) { |
| iofd_msghdr_free(msghdr); |
| LOGPIO(iofd, LOGL_ERROR, "enqueueing message failed (%d). Rejecting msgb\n", rc); |
| return rc; |
| } |
| |
| return 0; |
| } |
| |
| static int check_mode_callback_compat(enum osmo_io_fd_mode mode, const struct osmo_io_ops *ops) |
| { |
| switch (mode) { |
| case OSMO_IO_FD_MODE_READ_WRITE: |
| if (ops->recvfrom_cb || ops->sendto_cb) |
| return false; |
| if (ops->recvmsg_cb || ops->sendmsg_cb) |
| return false; |
| /* Forbid both segementation_cb set, something is wrong: */ |
| if (ops->segmentation_cb && ops->segmentation_cb2) |
| return false; |
| break; |
| case OSMO_IO_FD_MODE_RECVFROM_SENDTO: |
| if (ops->read_cb || ops->write_cb) |
| return false; |
| if (ops->recvmsg_cb || ops->sendmsg_cb) |
| return false; |
| break; |
| case OSMO_IO_FD_MODE_RECVMSG_SENDMSG: |
| if (ops->recvfrom_cb || ops->sendto_cb) |
| return false; |
| if (ops->read_cb || ops->write_cb) |
| return false; |
| break; |
| default: |
| break; |
| } |
| |
| return true; |
| } |
| |
| /*! Allocate and setup a new iofd. |
| * |
| * Use this to create a new osmo_io_fd, specifying the osmo_io_fd_mode and osmo_io_ops, as well as optionally |
| * the file-descriptor number and a human-readable name. This is the first function you call for any |
| * osmo_io_fd. |
| * |
| * The created osmo_io_fd is not yet registered, and hence can not be used for any I/O until a subsequent |
| * call to osmo_iofd_register(). |
| * |
| * The created osmo_io_fd is initialized with some default settings: |
| * * msgb allocations size: OSMO_IO_DEFAULT_MSGB_SIZE (1024) |
| * * msgb headroom: OSMO_IO_DEFAULT_MSGB_HEADROOM (128) |
| * * tx_queue depth: 32 |
| * |
| * Those values may be adjusted from their defaults by using osmo_iofd_set_alloc_info() and |
| * osmo_iofd_set_txqueue_max_length() on the osmo_io_fd. |
| * |
| * \param[in] ctx the parent context from which to allocate |
| * \param[in] fd the underlying system file descriptor. May be -1 if not known yet; must then be specified |
| * at subsequent osmo_iofd_register() time. |
| * \param[in] name the optional human-readable name of the iofd; may be NULL |
| * \param[in] mode the osmo_io_fd_mode of the iofd, whether it should use read()/write(), sendto()/recvfrom() |
| * semantics. |
| * \param[in] ioops structure specifying the read/write/send/recv callbacks. Will be copied to the iofd, so |
| * the caller does not have to keep it around after issuing the osmo_iofd_setup call. |
| * \param[in] data opaque user data pointer accessible by the ioops callbacks |
| * \returns The newly allocated osmo_io_fd struct or NULL on failure |
| */ |
| struct osmo_io_fd *osmo_iofd_setup(const void *ctx, int fd, const char *name, enum osmo_io_fd_mode mode, |
| const struct osmo_io_ops *ioops, void *data) |
| { |
| struct osmo_io_fd *iofd; |
| |
| /* reject unsupported/unknown modes */ |
| switch (mode) { |
| case OSMO_IO_FD_MODE_READ_WRITE: |
| case OSMO_IO_FD_MODE_RECVFROM_SENDTO: |
| case OSMO_IO_FD_MODE_RECVMSG_SENDMSG: |
| break; |
| default: |
| return NULL; |
| } |
| |
| if (ioops && !check_mode_callback_compat(mode, ioops)) { |
| LOGP(DLIO, LOGL_ERROR, "iofd(%s): rejecting call-backs incompatible with mode %s\n", |
| name ? name : "unknown", osmo_iofd_mode_name(mode)); |
| return NULL; |
| } |
| |
| iofd = talloc_zero(ctx, struct osmo_io_fd); |
| if (!iofd) |
| return NULL; |
| |
| iofd->fd = fd; |
| iofd->mode = mode; |
| IOFD_FLAG_SET(iofd, IOFD_FLAG_CLOSED); |
| |
| if (name) |
| iofd->name = talloc_strdup(iofd, name); |
| |
| if (ioops) |
| iofd->io_ops = *ioops; |
| |
| iofd->pending = NULL; |
| |
| iofd->data = data; |
| |
| iofd->msgb_alloc.ctx = ctx; |
| iofd->msgb_alloc.size = OSMO_IO_DEFAULT_MSGB_SIZE; |
| iofd->msgb_alloc.headroom = OSMO_IO_DEFAULT_MSGB_HEADROOM; |
| |
| iofd->tx_queue.max_length = 32; |
| INIT_LLIST_HEAD(&iofd->tx_queue.msg_queue); |
| |
| return iofd; |
| } |
| |
| /*! Set the size of the control message buffer allocated when submitting recvmsg. |
| * |
| * If your osmo_io_fd is in OSMO_IO_FD_MODE_RECVMSG_SENDMSG mode, this API function can be used to tell the |
| * osmo_io code how much memory should be allocated for the cmsg (control message) buffer when performing |
| * recvmsg(). */ |
| int osmo_iofd_set_cmsg_size(struct osmo_io_fd *iofd, size_t cmsg_size) |
| { |
| if (iofd->mode != OSMO_IO_FD_MODE_RECVMSG_SENDMSG) |
| return -EINVAL; |
| |
| iofd->cmsg_size = cmsg_size; |
| return 0; |
| } |
| |
| /*! Register the osmo_io_fd for active I/O. |
| * |
| * Calling this function will register a previously initialized osmo_io_fd for performing I/O. |
| * |
| * If the osmo_iofd has a read_cb/recvfrom_cb_recvmsg_cb set in its osmo_io_ops, read/receive will be |
| * automatically enabled and the respective call-back is called at any time data becomes available. |
| * |
| * If there is to-be-transmitted data in the transmit queue, write will be automatically enabled, allowing |
| * the transmit queue to be drained as soon as the fd/socket becomes writable. |
| * |
| * \param[in] iofd the iofd file descriptor |
| * \param[in] fd the system fd number that will be registered. If you did not yet specify the file descriptor |
| * number during osmo_fd_setup(), or if it has changed since then, you can state the [new] file descriptor |
| * number as argument. If you wish to proceed with the previously specified file descriptor number, pass -1. |
| * \returns zero on success, a negative value on error |
| */ |
| int osmo_iofd_register(struct osmo_io_fd *iofd, int fd) |
| { |
| int rc = 0; |
| |
| if (fd >= 0) |
| iofd->fd = fd; |
| else if (iofd->fd < 0) { |
| /* this might happen if both osmo_iofd_setup() and osmo_iofd_register() are called with -1 */ |
| LOGPIO(iofd, LOGL_ERROR, "Cannot register io_fd using invalid fd == %d\n", iofd->fd); |
| return -EBADF; |
| } |
| |
| rc = osmo_iofd_ops.register_fd(iofd); |
| if (rc) |
| return rc; |
| |
| IOFD_FLAG_UNSET(iofd, IOFD_FLAG_CLOSED); |
| if ((iofd->mode == OSMO_IO_FD_MODE_READ_WRITE && iofd->io_ops.read_cb) || |
| (iofd->mode == OSMO_IO_FD_MODE_RECVFROM_SENDTO && iofd->io_ops.recvfrom_cb) || |
| (iofd->mode == OSMO_IO_FD_MODE_RECVMSG_SENDMSG && iofd->io_ops.recvmsg_cb)) { |
| osmo_iofd_ops.read_enable(iofd); |
| } |
| |
| if (iofd->tx_queue.current_length > 0) |
| osmo_iofd_ops.write_enable(iofd); |
| |
| return rc; |
| } |
| |
| /*! Unregister the given osmo_io_fd from osmo_io. |
| * |
| * After an osmo_io_fd has been successfully unregistered, it can no longer perform any I/O via osmo_io. |
| * However, it can be subsequently re-registered using osmo_iofd_register(). |
| * |
| * \param[in] iofd the file descriptor |
| * \returns zero on success, a negative value on error |
| */ |
| int osmo_iofd_unregister(struct osmo_io_fd *iofd) |
| { |
| return osmo_iofd_ops.unregister_fd(iofd); |
| } |
| |
| /*! Retrieve the number of messages pending in the transmit queue. |
| * |
| * \param[in] iofd the file descriptor |
| */ |
| unsigned int osmo_iofd_txqueue_len(struct osmo_io_fd *iofd) |
| { |
| return iofd->tx_queue.current_length; |
| } |
| |
| /*! Clear the transmit queue of the given osmo_io_fd. |
| * |
| * This function frees all messages currently pending in the transmit queue |
| * \param[in] iofd the file descriptor |
| */ |
| void osmo_iofd_txqueue_clear(struct osmo_io_fd *iofd) |
| { |
| struct iofd_msghdr *hdr; |
| while ((hdr = iofd_txqueue_dequeue(iofd))) { |
| msgb_free(hdr->msg); |
| iofd_msghdr_free(hdr); |
| } |
| } |
| |
| /*! Free the given osmo_io_fd. |
| * |
| * The iofd will be automatically closed before via osmo_iofd_close() [which in turn will unregister |
| * it and clear any pending transmit queue items]. You must not reference the iofd |
| * after calling this function. However, it is safe to call this function from any of osmo_io |
| * call-backs; in this case, actual free will be internally delayed until that call-back completes. |
| * |
| * \param[in] iofd the file descriptor |
| */ |
| void osmo_iofd_free(struct osmo_io_fd *iofd) |
| { |
| if (!iofd) |
| return; |
| |
| osmo_iofd_close(iofd); |
| |
| if (!IOFD_FLAG_ISSET(iofd, IOFD_FLAG_IN_CALLBACK)) { |
| talloc_free(iofd); |
| } else { |
| /* Prevent our parent context from freeing us prematurely */ |
| talloc_steal(NULL, iofd); |
| IOFD_FLAG_SET(iofd, IOFD_FLAG_TO_FREE); |
| } |
| } |
| |
| /*! Close the given osmo_io_fd. |
| * |
| * This function closes the underlying fd, unregisters it from osmo_io and clears any messages in the tx |
| * queue. The iofd itself is not freed and can be assigned a new file descriptor with osmo_iofd_register() |
| * \param[in] iofd the file descriptor |
| * \returns 0 on success, a negative value otherwise |
| */ |
| int osmo_iofd_close(struct osmo_io_fd *iofd) |
| { |
| int rc = 0; |
| |
| if (IOFD_FLAG_ISSET(iofd, IOFD_FLAG_CLOSED)) |
| return rc; |
| |
| IOFD_FLAG_SET(iofd, IOFD_FLAG_CLOSED); |
| |
| /* Free pending msgs in tx queue */ |
| osmo_iofd_txqueue_clear(iofd); |
| msgb_free(iofd->pending); |
| |
| iofd->pending = NULL; |
| |
| rc = osmo_iofd_ops.close(iofd); |
| iofd->fd = -1; |
| return rc; |
| } |
| |
| /*! Set the size and headroom of the msgb allocated when receiving messages. |
| * \param[in] iofd the file descriptor |
| * \param[in] size the size of the msgb when receiving data |
| * \param[in] headroom the headroom of the msgb when receiving data |
| */ |
| void osmo_iofd_set_alloc_info(struct osmo_io_fd *iofd, unsigned int size, unsigned int headroom) |
| { |
| iofd->msgb_alloc.headroom = headroom; |
| iofd->msgb_alloc.size = size; |
| } |
| |
| /*! Set the maximum number of messages enqueued for sending. |
| * \param[in] iofd the file descriptor |
| * \param[in] size the maximum size of the transmit queue |
| */ |
| void osmo_iofd_set_txqueue_max_length(struct osmo_io_fd *iofd, unsigned int max_length) |
| { |
| iofd->tx_queue.max_length = max_length; |
| } |
| |
| /*! Retrieve the associated user-data from an osmo_io_fd. |
| * |
| * A call to this function will return the opaque user data pointer which was specified previously |
| * via osmo_iofd_setup() or via osmo_iofd_set_data(). |
| * |
| * \param[in] iofd the file descriptor |
| * \returns the data that was previously set with \ref osmo_iofd_setup() |
| */ |
| void *osmo_iofd_get_data(const struct osmo_io_fd *iofd) |
| { |
| return iofd->data; |
| } |
| |
| /*! Set the associated user-data from an osmo_io_fd. |
| * |
| * Calling this function will set/overwrite the opaque user data pointer, which can later be retrieved using |
| * osmo_iofd_get_data(). |
| * |
| * \param[in] iofd the file descriptor |
| * \param[in] data the data to set |
| */ |
| void osmo_iofd_set_data(struct osmo_io_fd *iofd, void *data) |
| { |
| iofd->data = data; |
| } |
| |
| /*! Retrieve the private number from an osmo_io_fd. |
| * Calling this function will retrieve the private user number previously set via osmo_iofd_set_priv_nr(). |
| * \param[in] iofd the file descriptor |
| * \returns the private number that was previously set with \ref osmo_iofd_set_priv_nr() |
| */ |
| unsigned int osmo_iofd_get_priv_nr(const struct osmo_io_fd *iofd) |
| { |
| return iofd->priv_nr; |
| } |
| |
| /*! Set the private number of an osmo_io_fd. |
| * The priv_nr passed in via this call can later be retrieved via osmo_iofd_get_priv_nr(). It provides |
| * a way how additional context can be stored in the osmo_io_fd beyond the opaque 'data' pointer. |
| * \param[in] iofd the file descriptor |
| * \param[in] priv_nr the private number to set |
| */ |
| void osmo_iofd_set_priv_nr(struct osmo_io_fd *iofd, unsigned int priv_nr) |
| { |
| iofd->priv_nr = priv_nr; |
| } |
| |
| /*! Retrieve the underlying file descriptor from an osmo_io_fd. |
| * \param[in] iofd the file descriptor |
| * \returns the underlying file descriptor number */ |
| int osmo_iofd_get_fd(const struct osmo_io_fd *iofd) |
| { |
| return iofd->fd; |
| } |
| |
| /*! Retrieve the human-readable name of the given osmo_io_fd. |
| * \param[in] iofd the file descriptor |
| * \returns the name of the iofd as given in \ref osmo_iofd_setup() */ |
| const char *osmo_iofd_get_name(const struct osmo_io_fd *iofd) |
| { |
| return iofd->name; |
| } |
| |
| /*! Set the human-readable name of the file descriptor. |
| * The given name will be used as context by all related logging and future calls to osmo_iofd_get_name(). |
| * \param[in] iofd the file descriptor |
| * \param[in] name the name to set on the file descriptor */ |
| void osmo_iofd_set_name(struct osmo_io_fd *iofd, const char *name) |
| { |
| osmo_talloc_replace_string(iofd, &iofd->name, name); |
| } |
| |
| /*! Set the osmo_io_ops calbacks for an osmo_io_fd. |
| * This function can be used to update/overwrite the call-back functions for the given osmo_io_fd; it |
| * replaces the currently-set call-back function pointers from a previous call to osmo_iofd_set_ioops() |
| * or the original osmo_iofd_setup(). |
| * \param[in] iofd Target iofd file descriptor |
| * \param[in] ioops osmo_io_ops structure to be copied to the osmo_io_fd. |
| * \returns 0 on success, negative on error */ |
| int osmo_iofd_set_ioops(struct osmo_io_fd *iofd, const struct osmo_io_ops *ioops) |
| { |
| if (!check_mode_callback_compat(iofd->mode, ioops)) { |
| LOGPIO(iofd, LOGL_ERROR, "rejecting call-backs incompatible with mode %s\n", |
| osmo_iofd_mode_name(iofd->mode)); |
| return -EINVAL; |
| } |
| |
| iofd->io_ops = *ioops; |
| |
| switch (iofd->mode) { |
| case OSMO_IO_FD_MODE_READ_WRITE: |
| if (iofd->io_ops.read_cb) |
| osmo_iofd_ops.read_enable(iofd); |
| else |
| osmo_iofd_ops.read_disable(iofd); |
| break; |
| case OSMO_IO_FD_MODE_RECVFROM_SENDTO: |
| if (iofd->io_ops.recvfrom_cb) |
| osmo_iofd_ops.read_enable(iofd); |
| else |
| osmo_iofd_ops.read_disable(iofd); |
| break; |
| case OSMO_IO_FD_MODE_RECVMSG_SENDMSG: |
| if (iofd->io_ops.recvmsg_cb) |
| osmo_iofd_ops.read_enable(iofd); |
| else |
| osmo_iofd_ops.read_disable(iofd); |
| break; |
| default: |
| OSMO_ASSERT(0); |
| } |
| |
| return 0; |
| } |
| |
| /*! Retrieve the osmo_io_ops for an iofd. |
| * \param[in] iofd Target iofd file descriptor |
| * \param[in] ioops caller-allocated osmo_io_ops structure to be filled */ |
| void osmo_iofd_get_ioops(struct osmo_io_fd *iofd, struct osmo_io_ops *ioops) |
| { |
| *ioops = iofd->io_ops; |
| } |
| |
| /*! Request notification of the user if/when a client socket is connected. |
| * Calling this function will request osmo_io to notify the user (via |
| * write call-back) once a non-blocking outbound connect() of the |
| * socket completes. |
| * |
| * This only works for connection oriented sockets in either |
| * OSMO_IO_FD_MODE_READ_WRITE or OSMO_IO_FD_MODE_RECVMSG_SENDMSG mode. |
| * |
| * \param[in] iofd the file descriptor */ |
| void osmo_iofd_notify_connected(struct osmo_io_fd *iofd) |
| { |
| OSMO_ASSERT(iofd->mode == OSMO_IO_FD_MODE_READ_WRITE || |
| iofd->mode == OSMO_IO_FD_MODE_RECVMSG_SENDMSG); |
| osmo_iofd_ops.notify_connected(iofd); |
| } |
| |
| /*! @} */ |
| |
| #endif /* ifndef(EMBEDDED) */ |