source/libcli/clireadwrite.c

   1 /*
   2    Unix SMB/CIFS implementation.
   3    client file read/write routines
   4    Copyright (C) Andrew Tridgell 1994-1998
   5    Copyright (C) James Myers 2003
   6
   7    This program is free software; you can redistribute it and/or modify
   8    it under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 2 of the License, or
  10    (at your option) any later version.
  11
  12    This program is distributed in the hope that it will be useful,
  13    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15    GNU General Public License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with this program; if not, write to the Free Software
  19    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  20 */
  21
  22 #include "includes.h"
  23
  24 /****************************************************************************
  25   Read size bytes at offset offset using SMBreadX.
  26 ****************************************************************************/
  27 ssize_t smbcli_read(struct smbcli_tree *tree, int fnum, char *buf, off_t offset,
  28                  size_t size)
  29 {
  30         union smb_read parms;
  31         int readsize;
  32         ssize_t total = 0;
  33
  34         if (size == 0) {
  35                 return 0;
  36         }
  37
  38         parms.readx.level = RAW_READ_READX;
  39         parms.readx.in.fnum = fnum;
  40
  41         /*
  42          * Set readsize to the maximum size we can handle in one readX,
  43          * rounded down to a multiple of 1024.
  44          */
  45         readsize = (tree->session->transport->negotiate.max_xmit - (MIN_SMB_SIZE+32));
  46         if (readsize > 0xFFFF) readsize = 0xFFFF;
  47
  48         while (total < size) {
  49                 NTSTATUS status;
  50
  51                 readsize = MIN(readsize, size-total);
  52
  53                 parms.readx.in.offset    = offset;
  54                 parms.readx.in.mincnt    = readsize;
  55                 parms.readx.in.maxcnt    = readsize;
  56                 parms.readx.in.remaining = size - total;
  57                 parms.readx.out.data     = buf + total;
  58
  59                 status = smb_raw_read(tree, &parms);
  60
  61                 if (!NT_STATUS_IS_OK(status)) {
  62                         return -1;
  63                 }
  64
  65                 total += parms.readx.out.nread;
  66                 offset += parms.readx.out.nread;
  67
  68                 /* If the server returned less than we asked for we're at EOF */
  69                 if (parms.readx.out.nread < readsize)
  70                         break;
  71         }
  72
  73         return total;
  74 }
  75
  76
  77 /****************************************************************************
  78   write to a file
  79   write_mode: 0x0001 disallow write cacheing
  80               0x0002 return bytes remaining
  81               0x0004 use raw named pipe protocol
  82               0x0008 start of message mode named pipe protocol
  83 ****************************************************************************/
  84 ssize_t smbcli_write(struct smbcli_tree *tree,
  85                      int fnum, uint16_t write_mode,
  86                      const uint8_t *buf, off_t offset, size_t size)
  87 {
  88         union smb_write parms;
  89         int block = (tree->session->transport->negotiate.max_xmit - (MIN_SMB_SIZE+32));
  90         ssize_t total = 0;
  91
  92         if (size == 0) {
  93                 return 0;
  94         }
  95
  96         if (block > 0xFFFF) block = 0xFFFF;
  97
  98
  99         parms.writex.level = RAW_WRITE_WRITEX;
 100         parms.writex.in.fnum = fnum;
 101         parms.writex.in.wmode = write_mode;
 102         parms.writex.in.remaining = 0;
 103
 104         while (total < size) {
 105                 NTSTATUS status;
 106
 107                 block = MIN(block, size - total);
 108
 109                 parms.writex.in.offset = offset;
 110                 parms.writex.in.count = block;
 111                 parms.writex.in.data = buf;
 112
 113                 status = smb_raw_write(tree, &parms);
 114
 115                 if (!NT_STATUS_IS_OK(status)) {
 116                         return -1;
 117                 }
 118
 119                 offset += parms.writex.out.nwritten;
 120                 total += parms.writex.out.nwritten;
 121                 buf += parms.writex.out.nwritten;
 122         }
 123
 124         return total;
 125 }
 126
 127 /****************************************************************************
 128   write to a file using a SMBwrite and not bypassing 0 byte writes
 129 ****************************************************************************/
 130 ssize_t smbcli_smbwrite(struct smbcli_tree *tree,
 131                      int fnum, char *buf, off_t offset, size_t size1)
 132 {
 133         union smb_write parms;
 134         ssize_t total = 0;
 135
 136         parms.write.level = RAW_WRITE_WRITE;
 137         parms.write.in.remaining = 0;
 138
 139         do {
 140                 size_t size = MIN(size1, tree->session->transport->negotiate.max_xmit - 48);
 141                 if (size > 0xFFFF) size = 0xFFFF;
 142
 143                 parms.write.in.fnum = fnum;
 144                 parms.write.in.offset = offset;
 145                 parms.write.in.count = size;
 146                 parms.write.in.data = buf + total;
 147
 148                 if (NT_STATUS_IS_ERR(smb_raw_write(tree, &parms)))
 149                         return -1;
 150
 151                 size = parms.write.out.nwritten;
 152                 if (size == 0)
 153                         break;
 154
 155                 size1 -= size;
 156                 total += size;
 157                 offset += size;
 158         } while (size1);
 159
 160         return total;
 161 }