diff options
| -rw-r--r-- | libdiskfs/node-rdwr.c | 65 |
1 files changed, 65 insertions, 0 deletions
diff --git a/libdiskfs/node-rdwr.c b/libdiskfs/node-rdwr.c new file mode 100644 index 00000000..4ee9a213 --- /dev/null +++ b/libdiskfs/node-rdwr.c @@ -0,0 +1,65 @@ +/* + Copyright (C) 1994 Free Software Foundation + + 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, 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. */ + +#include "priv.h" + +/* Reading and writing of files. this is called by other filesystem + routines and handles extension of files and reads of more than is + left automatically. NP is the node to be read or written. DATA + will be written or filled. OFF identifies where in thi fel the I/O + is to take place (-1 is not allowed). AMT is the size of DATA and + tells how much to copy. DIR is 1 for writing and 0 for reading. + CRED is the user doing the access (only used to validate attempted + file extension). */ +error_t +diskfs_noderdwr (struct inode *ip, + char *data, + off_t off, + int amt, + int dir, + struct protid *cred) +{ + error_t err; + + if (err = ioserver_get_conch (&ip->i_conch)) + return err; + + if (!(err = catch_exception ())) + { + if (dir) + while (off + amt > ip->i_allocsize) + if (err = file_extend (ip, off + amt, cred)) + return err; + + if (off + amt > ip->di->di_size) + { + assert (dir); /* reads can't go past EOF internally */ + if (dir) + { + ip->di->di_size = off + amt; + ip->di->di_ctime = wallclock->seconds; + } + } + end_catch_exception (); + } + if (err) + return err; + + err = io_rdwr (ip, data, off, amt, dir); + + return err; +} |