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-rw-r--r--source4/lib/sendfile.c382
1 files changed, 382 insertions, 0 deletions
diff --git a/source4/lib/sendfile.c b/source4/lib/sendfile.c
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+/*
+ 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 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.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software
+ Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/*
+ * 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"
+
+#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, SMB_OFF_T offset, size_t count)
+{
+ size_t total=0;
+ ssize_t ret;
+ size_t hdr_len = 0;
+
+ /*
+ * 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)
+ return -1;
+ total += ret;
+ }
+ }
+
+ total = count;
+ while (total) {
+ ssize_t nwritten;
+ do {
+#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(HAVE_SENDFILE64)
+ nwritten = sendfile64(tofd, fromfd, &offset, total);
+#else
+ nwritten = sendfile(tofd, fromfd, &offset, total);
+#endif
+ } while (nwritten == -1 && errno == EINTR);
+ if (nwritten == -1)
+ return -1;
+ if (nwritten == 0)
+ return -1; /* I think we're at EOF here... */
+ total -= nwritten;
+ }
+ return count + hdr_len;
+}
+
+#elif defined(LINUX_BROKEN_SENDFILE_API)
+
+/*
+ * We must use explicit 32 bit types here. This code path means Linux
+ * won't do proper 64-bit sendfile. JRA.
+ */
+
+extern int32 sendfile (int out_fd, int in_fd, int32 *offset, uint32 count);
+
+
+#ifndef MSG_MORE
+#define MSG_MORE 0x8000
+#endif
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count)
+{
+ size_t total=0;
+ ssize_t ret;
+ ssize_t hdr_len = 0;
+ uint32 small_total = 0;
+ int32 small_offset;
+
+ /*
+ * Fix for broken Linux 2.4 systems with no working sendfile64().
+ * If the offset+count > 2 GB then pretend we don't have the
+ * system call sendfile at all. The upper layer catches this
+ * and uses a normal read. JRA.
+ */
+
+ if ((sizeof(SMB_OFF_T) >= 8) && (offset + count > (SMB_OFF_T)0x7FFFFFFF)) {
+ errno = ENOSYS;
+ return -1;
+ }
+
+ /*
+ * 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)
+ return -1;
+ total += ret;
+ }
+ }
+
+ small_total = (uint32)count;
+ small_offset = (int32)offset;
+
+ while (small_total) {
+ int32 nwritten;
+ do {
+ nwritten = sendfile(tofd, fromfd, &small_offset, small_total);
+ } while (nwritten == -1 && errno == EINTR);
+ if (nwritten == -1)
+ return -1;
+ if (nwritten == 0)
+ return -1; /* I think we're at EOF here... */
+ small_total -= nwritten;
+ }
+ return count + hdr_len;
+}
+
+
+#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, SMB_OFF_T offset, size_t count)
+{
+ int sfvcnt;
+ size_t total, xferred;
+ struct sendfilevec vec[2];
+ ssize_t hdr_len = 0;
+
+ if (header) {
+ sfvcnt = 2;
+
+ vec[0].sfv_fd = SFV_FD_SELF;
+ vec[0].sfv_flag = 0;
+ vec[0].sfv_off = 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;
+
+#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(HAVE_SENDFILEV64)
+ nwritten = sendfilev64(tofd, vec, sfvcnt, &xferred);
+#else
+ nwritten = sendfilev(tofd, vec, sfvcnt, &xferred);
+#endif
+ if (nwritten == -1 && errno == EINTR) {
+ if (xferred == 0)
+ continue; /* Nothing written yet. */
+ else
+ nwritten = xferred;
+ }
+
+ if (nwritten == -1)
+ return -1;
+ if (nwritten == 0)
+ return -1; /* 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;
+ }
+ return count + hdr_len;
+}
+
+#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, SMB_OFF_T offset, size_t count)
+{
+ size_t total=0;
+ struct iovec hdtrl[2];
+ size_t hdr_len = 0;
+
+ if (header) {
+ /* Set up the header/trailer iovec. */
+ hdtrl[0].iov_base = 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_base = 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 {
+#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(HAVE_SENDFILE64)
+ nwritten = sendfile64(tofd, fromfd, offset, total, &hdtrl[0], 0);
+#else
+ nwritten = sendfile(tofd, fromfd, offset, total, &hdtrl[0], 0);
+#endif
+ } while (nwritten == -1 && errno == EINTR);
+ if (nwritten == -1)
+ return -1;
+ if (nwritten == 0)
+ return -1; /* 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 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 = ((char *)hdtrl[0].iov_base) + nwritten;
+ hdtrl[0].iov_len -= nwritten;
+ nwritten = 0;
+ }
+ }
+ total -= nwritten;
+ offset += nwritten;
+ }
+ return count + hdr_len;
+}
+
+#elif defined(FREEBSD_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, SMB_OFF_T offset, size_t count)
+{
+ size_t total=0;
+ struct sf_hdtr hdr;
+ struct iovec hdtrl;
+ size_t hdr_len = 0;
+
+ hdr.headers = &hdtrl;
+ hdr.hdr_cnt = 1;
+ hdr.trailers = NULL;
+ hdr.trl_cnt = 0;
+
+ /* Set up the header iovec. */
+ if (header) {
+ hdtrl.iov_base = header->data;
+ hdtrl.iov_len = hdr_len = header->length;
+ } else {
+ hdtrl.iov_base = NULL;
+ hdtrl.iov_len = 0;
+ }
+
+ total = count;
+ while (total + hdtrl.iov_len) {
+ SMB_OFF_T nwritten;
+ int ret;
+
+ /*
+ * FreeBSD sendfile returns 0 on success, -1 on error.
+ * Remember, the tofd and fromfd are reversed..... :-).
+ * nwritten includes the header data sent.
+ */
+
+ do {
+ ret = sendfile(fromfd, tofd, offset, total, &hdr, &nwritten, 0);
+ } while (ret == -1 && errno == EINTR);
+ if (ret == -1)
+ return -1;
+
+ if (nwritten == 0)
+ return -1; /* 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 hdtrl.iov_len bytes.
+ * We change nwritten to be the number of file bytes written.
+ */
+
+ if (hdtrl.iov_base && hdtrl.iov_len) {
+ if (nwritten >= hdtrl.iov_len) {
+ nwritten -= hdtrl.iov_len;
+ hdtrl.iov_base = NULL;
+ hdtrl.iov_len = 0;
+ } else {
+ hdtrl.iov_base += nwritten;
+ hdtrl.iov_len -= nwritten;
+ nwritten = 0;
+ }
+ }
+ total -= nwritten;
+ offset += nwritten;
+ }
+ return count + hdr_len;
+}
+
+#else /* No sendfile implementation. Return error. */
+
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count)
+{
+ /* No sendfile syscall. */
+ errno = ENOSYS;
+ return -1;
+}
+#endif