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-rw-r--r--source3/lib/sendfile.c602
1 files changed, 602 insertions, 0 deletions
diff --git a/source3/lib/sendfile.c b/source3/lib/sendfile.c
new file mode 100644
index 0000000..69c89d2
--- /dev/null
+++ b/source3/lib/sendfile.c
@@ -0,0 +1,602 @@
+/*
+ Unix SMB/Netbios implementation.
+ Version 2.2.x / 3.0.x
+ sendfile implementations.
+ Copyright (C) Jeremy Allison 2002.
+
+ 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 3 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+ * This file handles the OS dependent sendfile implementations.
+ * The API is such that it returns -1 on error, else returns the
+ * number of bytes written.
+ */
+
+#include "includes.h"
+#include "system/filesys.h"
+
+#if defined(LINUX_SENDFILE_API)
+
+#include <sys/sendfile.h>
+
+#ifndef MSG_MORE
+#define MSG_MORE 0x8000
+#endif
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
+{
+ size_t total=0;
+ ssize_t ret = -1;
+ size_t hdr_len = 0;
+ int old_flags = 0;
+ bool socket_flags_changed = false;
+
+ /*
+ * Send the header first.
+ * Use MSG_MORE to cork the TCP output until sendfile is called.
+ */
+
+ if (header) {
+ hdr_len = header->length;
+ while (total < hdr_len) {
+ ret = sys_send(tofd, header->data + total,hdr_len - total, MSG_MORE);
+ if (ret == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ /*
+ * send() must complete before we can
+ * send any other outgoing data on the
+ * socket. Ensure socket is in blocking
+ * mode. For SMB2 by default the socket
+ * is in non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+ goto out;
+ }
+ total += ret;
+ }
+ }
+
+ total = count;
+ while (total) {
+ ssize_t nwritten;
+ do {
+ nwritten = sendfile(tofd, fromfd, &offset, total);
+ } while (nwritten == -1 && errno == EINTR);
+ if (nwritten == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ if (socket_flags_changed) {
+ /*
+ * We're already in blocking
+ * mode. This is an error.
+ */
+ ret = -1;
+ goto out;
+ }
+
+ /*
+ * Sendfile must complete before we can
+ * send any other outgoing data on the socket.
+ * Ensure socket is in blocking mode.
+ * For SMB2 by default the socket is in
+ * non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+
+ if (errno == ENOSYS || errno == EINVAL) {
+ /* Ok - we're in a world of pain here. We just sent
+ * the header, but the sendfile failed. We have to
+ * emulate the sendfile at an upper layer before we
+ * disable it's use. So we do something really ugly.
+ * We set the errno to a strange value so we can detect
+ * this at the upper level and take care of it without
+ * layer violation. JRA.
+ */
+ errno = EINTR; /* Normally we can never return this. */
+ }
+ ret = -1;
+ goto out;
+ }
+ if (nwritten == 0) {
+ /*
+ * EOF, return a short read
+ */
+ ret = hdr_len + (count - total);
+ goto out;
+ }
+ total -= nwritten;
+ }
+
+ ret = count + hdr_len;
+
+ out:
+
+ if (socket_flags_changed) {
+ int saved_errno = errno;
+ int err;
+
+ /* Restore the old state of the socket. */
+ err = fcntl(tofd, F_SETFL, old_flags);
+ if (err == -1) {
+ return -1;
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ }
+ }
+
+ return ret;
+}
+
+#elif defined(SOLARIS_SENDFILE_API)
+
+/*
+ * Solaris sendfile code written by Pierre Belanger <belanger@pobox.com>.
+ */
+
+#include <sys/sendfile.h>
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
+{
+ int sfvcnt;
+ size_t total, xferred;
+ struct sendfilevec vec[2];
+ ssize_t hdr_len = 0;
+ int old_flags = 0;
+ ssize_t ret = -1;
+ bool socket_flags_changed = false;
+
+ if (header) {
+ sfvcnt = 2;
+
+ vec[0].sfv_fd = SFV_FD_SELF;
+ vec[0].sfv_flag = 0;
+ vec[0].sfv_off = (off_t)header->data;
+ vec[0].sfv_len = hdr_len = header->length;
+
+ vec[1].sfv_fd = fromfd;
+ vec[1].sfv_flag = 0;
+ vec[1].sfv_off = offset;
+ vec[1].sfv_len = count;
+
+ } else {
+ sfvcnt = 1;
+
+ vec[0].sfv_fd = fromfd;
+ vec[0].sfv_flag = 0;
+ vec[0].sfv_off = offset;
+ vec[0].sfv_len = count;
+ }
+
+ total = count + hdr_len;
+
+ while (total) {
+ ssize_t nwritten;
+
+ /*
+ * Although not listed in the API error returns, this is almost certainly
+ * a slow system call and will be interrupted by a signal with EINTR. JRA.
+ */
+
+ xferred = 0;
+
+ nwritten = sendfilev(tofd, vec, sfvcnt, &xferred);
+ if (nwritten == -1 && errno == EINTR) {
+ if (xferred == 0)
+ continue; /* Nothing written yet. */
+ else
+ nwritten = xferred;
+ }
+
+ if (nwritten == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ /*
+ * Sendfile must complete before we can
+ * send any other outgoing data on the socket.
+ * Ensure socket is in blocking mode.
+ * For SMB2 by default the socket is in
+ * non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+ ret = -1;
+ goto out;
+ }
+ if (nwritten == 0) {
+ ret = -1;
+ goto out; /* I think we're at EOF here... */
+ }
+
+ /*
+ * If this was a short (signal interrupted) write we may need
+ * to subtract it from the header data, or null out the header
+ * data altogether if we wrote more than vec[0].sfv_len bytes.
+ * We move vec[1].* to vec[0].* and set sfvcnt to 1
+ */
+
+ if (sfvcnt == 2 && nwritten >= vec[0].sfv_len) {
+ vec[1].sfv_off += nwritten - vec[0].sfv_len;
+ vec[1].sfv_len -= nwritten - vec[0].sfv_len;
+
+ /* Move vec[1].* to vec[0].* and set sfvcnt to 1 */
+ vec[0] = vec[1];
+ sfvcnt = 1;
+ } else {
+ vec[0].sfv_off += nwritten;
+ vec[0].sfv_len -= nwritten;
+ }
+ total -= nwritten;
+ }
+ ret = count + hdr_len;
+
+ out:
+
+ if (socket_flags_changed) {
+ int saved_errno;
+ int err;
+
+ if (ret == -1) {
+ saved_errno = errno;
+ }
+ /* Restore the old state of the socket. */
+ err = fcntl(tofd, F_SETFL, old_flags);
+ if (err == -1) {
+ return -1;
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ }
+ }
+
+ return ret;
+}
+
+#elif defined(HPUX_SENDFILE_API)
+
+#include <sys/socket.h>
+#include <sys/uio.h>
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
+{
+ size_t total=0;
+ struct iovec hdtrl[2];
+ size_t hdr_len = 0;
+ int old_flags = 0;
+ ssize_t ret = -1;
+ bool socket_flags_changed = false;
+
+ if (header) {
+ /* Set up the header/trailer iovec. */
+ hdtrl[0].iov_base = (void *)header->data;
+ hdtrl[0].iov_len = hdr_len = header->length;
+ } else {
+ hdtrl[0].iov_base = NULL;
+ hdtrl[0].iov_len = hdr_len = 0;
+ }
+ hdtrl[1].iov_base = NULL;
+ hdtrl[1].iov_len = 0;
+
+ total = count;
+ while (total + hdtrl[0].iov_len) {
+ ssize_t nwritten;
+
+ /*
+ * HPUX guarantees that if any data was written before
+ * a signal interrupt then sendfile returns the number of
+ * bytes written (which may be less than requested) not -1.
+ * nwritten includes the header data sent.
+ */
+
+ do {
+ nwritten = sendfile(tofd, fromfd, offset, total, &hdtrl[0], 0);
+ } while (nwritten == -1 && errno == EINTR);
+ if (nwritten == -1) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ /*
+ * Sendfile must complete before we can
+ * send any other outgoing data on the socket.
+ * Ensure socket is in blocking mode.
+ * For SMB2 by default the socket is in
+ * non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+ ret = -1;
+ goto out;
+ }
+ if (nwritten == 0) {
+ ret = -1; /* I think we're at EOF here... */
+ goto out;
+ }
+
+ /*
+ * If this was a short (signal interrupted) write we may need
+ * to subtract it from the header data, or null out the header
+ * data altogether if we wrote more than hdtrl[0].iov_len bytes.
+ * We change nwritten to be the number of file bytes written.
+ */
+
+ if (hdtrl[0].iov_base && hdtrl[0].iov_len) {
+ if (nwritten >= hdtrl[0].iov_len) {
+ nwritten -= hdtrl[0].iov_len;
+ hdtrl[0].iov_base = NULL;
+ hdtrl[0].iov_len = 0;
+ } else {
+ /* iov_base is defined as a void *... */
+ hdtrl[0].iov_base = (void *)(((char *)hdtrl[0].iov_base) + nwritten);
+ hdtrl[0].iov_len -= nwritten;
+ nwritten = 0;
+ }
+ }
+ total -= nwritten;
+ offset += nwritten;
+ }
+ ret = count + hdr_len;
+
+ out:
+
+ if (socket_flags_changed) {
+ int saved_errno;
+ int err;
+
+ if (ret == -1) {
+ saved_errno = errno;
+ }
+ /* Restore the old state of the socket. */
+ err = fcntl(tofd, F_SETFL, old_flags);
+ if (err == -1) {
+ return -1;
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ }
+ }
+
+ return ret;
+}
+
+#elif defined(FREEBSD_SENDFILE_API) || defined(DARWIN_SENDFILE_API)
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <sys/uio.h>
+
+ssize_t sys_sendfile(int tofd, int fromfd,
+ const DATA_BLOB *header, off_t offset, size_t count)
+{
+ struct sf_hdtr sf_header = {0};
+ struct iovec io_header = {0};
+ int old_flags = 0;
+
+ off_t nwritten;
+ ssize_t ret = -1;
+ bool socket_flags_changed = false;
+
+ if (header) {
+ sf_header.headers = &io_header;
+ sf_header.hdr_cnt = 1;
+ io_header.iov_base = header->data;
+ io_header.iov_len = header->length;
+ sf_header.trailers = NULL;
+ sf_header.trl_cnt = 0;
+ }
+
+ while (count != 0) {
+
+ nwritten = count;
+#if defined(DARWIN_SENDFILE_API)
+ /* Darwin recycles nwritten as a value-result parameter, apart from that this
+ sendfile implementation is quite the same as the FreeBSD one */
+ ret = sendfile(fromfd, tofd, offset, &nwritten, &sf_header, 0);
+#else
+ ret = sendfile(fromfd, tofd, offset, count, &sf_header, &nwritten, 0);
+#endif
+ if (ret == -1 && errno != EINTR) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ /*
+ * Sendfile must complete before we can
+ * send any other outgoing data on the socket.
+ * Ensure socket is in blocking mode.
+ * For SMB2 by default the socket is in
+ * non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+ /* Send failed, we are toast. */
+ ret = -1;
+ goto out;
+ }
+
+ if (nwritten == 0) {
+ /* EOF of offset is after EOF. */
+ break;
+ }
+
+ if (sf_header.hdr_cnt) {
+ if (io_header.iov_len <= nwritten) {
+ /* Entire header was sent. */
+ sf_header.headers = NULL;
+ sf_header.hdr_cnt = 0;
+ nwritten -= io_header.iov_len;
+ } else {
+ /* Partial header was sent. */
+ io_header.iov_len -= nwritten;
+ io_header.iov_base =
+ ((uint8_t *)io_header.iov_base) + nwritten;
+ nwritten = 0;
+ }
+ }
+
+ offset += nwritten;
+ count -= nwritten;
+ }
+
+ ret = nwritten;
+
+ out:
+
+ if (socket_flags_changed) {
+ int saved_errno;
+ int err;
+
+ if (ret == -1) {
+ saved_errno = errno;
+ }
+ /* Restore the old state of the socket. */
+ err = fcntl(tofd, F_SETFL, old_flags);
+ if (err == -1) {
+ return -1;
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ }
+ }
+
+ return ret;
+}
+
+#elif defined(AIX_SENDFILE_API)
+
+/* BEGIN AIX SEND_FILE */
+
+/* Contributed by William Jojo <jojowil@hvcc.edu> */
+#include <sys/socket.h>
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
+{
+ struct sf_parms hdtrl;
+ int old_flags = 0;
+ ssize_t ret = -1;
+ bool socket_flags_changed = false;
+
+ /* Set up the header/trailer struct params. */
+ if (header) {
+ hdtrl.header_data = header->data;
+ hdtrl.header_length = header->length;
+ } else {
+ hdtrl.header_data = NULL;
+ hdtrl.header_length = 0;
+ }
+ hdtrl.trailer_data = NULL;
+ hdtrl.trailer_length = 0;
+
+ hdtrl.file_descriptor = fromfd;
+ hdtrl.file_offset = offset;
+ hdtrl.file_bytes = count;
+
+ while ( hdtrl.file_bytes + hdtrl.header_length ) {
+ /*
+ Return Value
+
+ There are three possible return values from send_file:
+
+ Value Description
+
+ -1 an error has occurred, errno contains the error code.
+
+ 0 the command has completed successfully.
+
+ 1 the command was completed partially, some data has been
+ transmitted but the command has to return for some reason,
+ for example, the command was interrupted by signals.
+ */
+ do {
+ ret = send_file(&tofd, &hdtrl, 0);
+ } while ((ret == 1) || (ret == -1 && errno == EINTR));
+ if ( ret == -1 ) {
+ if (errno == EAGAIN || errno == EWOULDBLOCK) {
+ /*
+ * Sendfile must complete before we can
+ * send any other outgoing data on the socket.
+ * Ensure socket is in blocking mode.
+ * For SMB2 by default the socket is in
+ * non-blocking mode.
+ */
+ old_flags = fcntl(tofd, F_GETFL, 0);
+ ret = set_blocking(tofd, true);
+ if (ret == -1) {
+ goto out;
+ }
+ socket_flags_changed = true;
+ continue;
+ }
+ goto out;
+ }
+ }
+
+ ret = count + header->length;
+
+ out:
+
+ if (socket_flags_changed) {
+ int saved_errno;
+ int err;
+
+ if (ret == -1) {
+ saved_errno = errno;
+ }
+ /* Restore the old state of the socket. */
+ err = fcntl(tofd, F_SETFL, old_flags);
+ if (err == -1) {
+ return -1;
+ }
+ if (ret == -1) {
+ errno = saved_errno;
+ }
+ }
+
+ return ret;
+}
+/* END AIX SEND_FILE */
+
+#else /* No sendfile implementation. Return error. */
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
+{
+ /* No sendfile syscall. */
+ errno = ENOSYS;
+ return -1;
+}
+#endif
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