lib/util: Standardize use of st_[acm]time ns
[samba.git] / source3 / lib / sendfile.c
index 6e093c31ffb999da94cc8b376a2e01b875eac5b3..d3effaf30aa4537d24741c59db3dbc4afefd9839 100644 (file)
@@ -6,7 +6,7 @@
 
  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
+ 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
@@ -14,8 +14,7 @@
  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.
+ along with this program; if not, see <http://www.gnu.org/licenses/>.
 */
 
 /*
@@ -25,6 +24,7 @@
  */
 
 #include "includes.h"
+#include "system/filesys.h"
 
 #if defined(LINUX_SENDFILE_API)
 
 #define MSG_MORE 0x8000
 #endif
 
-ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count)
+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;
-       ssize_t hdr_len = 0;
+       ssize_t ret = -1;
+       size_t hdr_len = 0;
+       int old_flags = 0;
+       bool socket_flags_changed = false;
 
        /*
         * Send the header first.
@@ -47,10 +49,27 @@ ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T of
 
        if (header) {
                hdr_len = header->length;
-               while (total < hd_len) {
+               while (total < hdr_len) {
                        ret = sys_send(tofd, header->data + total,hdr_len - total, MSG_MORE);
-                       if (ret == -1)
-                               return -1;
+                       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;
                }
        }
@@ -59,25 +78,210 @@ ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T of
        while (total) {
                ssize_t nwritten;
                do {
-#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(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... */
+               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;
        }
-       return count + hdr_len;
+
+       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(SOLARIS_SENDFILE_API)
 
-ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T offset, size_t count)
+/*
+ * 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)
@@ -85,22 +289,25 @@ ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T of
 #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)
+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 = header->data;
+               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_base = 0;
+       hdtrl[1].iov_len = 0;
 
        total = count;
        while (total + hdtrl[0].iov_len) {
@@ -114,16 +321,32 @@ ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T of
                 */
 
                do {
-#if defined(HAVE_EXPLICIT_LARGEFILE_SUPPORT) && defined(HAVE_OFF64_T) && defined(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 (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
@@ -138,91 +361,242 @@ ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, SMB_OFF_T of
                                hdtrl[0].iov_base = NULL;
                                hdtrl[0].iov_len = 0;
                        } else {
-                               nwritten = 0;
-                               hdtrl[0].iov_base += nwritten;
+                               /* 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;
        }
-       return count + hdr_len;
+       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)
+#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, SMB_OFF_T offset, size_t count)
+ssize_t sys_sendfile(int tofd, int fromfd,
+           const DATA_BLOB *header, off_t offset, size_t count)
 {
-       size_t total=0;
-       struct sf_hdtr hdr;
-       struct iovec hdtrl;
-       size_t hdr_len = 0;
+       struct sf_hdtr  sf_header = {0};
+       struct iovec    io_header = {0};
+       int old_flags = 0;
 
-       hdr->headers = &hdtrl;
-       hdr->hdr_cnt = 1;
-       hdr->trailers = NULL;
-       hdr->trl_cnt = 0;
+       off_t   nwritten;
+       ssize_t ret = -1;
+       bool socket_flags_changed = false;
 
-       /* 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;
+               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;
        }
 
-       total = count;
-       while (total + hdtrl.iov_len) {
-               SMB_OFF_T nwritten;
-               int ret;
+       while (count != 0) {
 
-               /*
-                * FreeBSD sendfile returns 0 on success, -1 on error.
-                * Remember, the tofd and fromfd are reversed..... :-).
-                * nwritten includes the header data sent.
-                */
+               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;
+               }
 
-               do {
-                       ret = sendfile(fromfd, tofd, offset, total, &hdr, &nwritten, 0);
-               } while (ret == -1 && errno == EINTR);
-               if (ret == -1)
+               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)
 
-               if (nwritten == 0)
-                       return -1; /* I think we're at EOF here... */
+/* 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 ) {
                /*
-                * 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.
-                */
+                Return Value
 
-               if (hdtrl[0].iov_base && hdtrl.iov_len) {
-                       if (nwritten >= hdtrl.iov_len) {
-                               nwritten -= hdtrl.iov_len;
-                               hdtrl.iov_base = NULL;
-                               hdtrl.iov_len = 0;
-                       } else {
-                               nwritten = 0;
-                               hdtrl.iov_base += nwritten;
-                               hdtrl.iov_len -= nwritten;
+                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;
                }
-               total -= nwritten;
-               offset += nwritten;
        }
-       return count + hdr_len;
+
+       return ret;
 }
+/* END AIX SEND_FILE */
 
 #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)
+ssize_t sys_sendfile(int tofd, int fromfd, const DATA_BLOB *header, off_t offset, size_t count)
 {
        /* No sendfile syscall. */
        errno = ENOSYS;