Annotation of sys/arch/mvmeppc/stand/libsa/rawfs.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: rawfs.c,v 1.2 2002/03/14 01:26:41 millert Exp $ */
! 2:
! 3: /*
! 4: * Copyright (c) 1995 Gordon W. Ross
! 5: * All rights reserved.
! 6: *
! 7: * Redistribution and use in source and binary forms, with or without
! 8: * modification, are permitted provided that the following conditions
! 9: * are met:
! 10: * 1. Redistributions of source code must retain the above copyright
! 11: * notice, this list of conditions and the following disclaimer.
! 12: * 2. Redistributions in binary form must reproduce the above copyright
! 13: * notice, this list of conditions and the following disclaimer in the
! 14: * documentation and/or other materials provided with the distribution.
! 15: * 3. The name of the author may not be used to endorse or promote products
! 16: * derived from this software without specific prior written permission.
! 17: * 4. All advertising materials mentioning features or use of this software
! 18: * must display the following acknowledgement:
! 19: * This product includes software developed by Gordon W. Ross
! 20: *
! 21: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
! 22: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
! 23: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
! 24: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
! 25: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
! 26: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
! 27: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
! 28: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
! 29: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
! 30: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
! 31: */
! 32:
! 33: /*
! 34: * Raw file system - for stream devices like tapes.
! 35: * No random access, only sequential read allowed.
! 36: * This exists only to allow upper level code to be
! 37: * shielded from the fact that the device must be
! 38: * read only with whole block position and size.
! 39: */
! 40:
! 41: #include <sys/param.h>
! 42: #include <stand.h>
! 43: #include <rawfs.h>
! 44:
! 45: #define RAWFS_BSIZE 512
! 46:
! 47: /*
! 48: * In-core open file.
! 49: */
! 50: struct cfile {
! 51: daddr_t fs_nextblk; /* block number to read next */
! 52: int fs_len; /* amount left in f_buf */
! 53: char * fs_ptr; /* read pointer into f_buf */
! 54: char fs_buf[RAWFS_BSIZE];
! 55: };
! 56:
! 57: static int
! 58: rawfs_get_block(struct open_file *);
! 59:
! 60: int rawfs_open(path, f)
! 61: char *path;
! 62: struct open_file *f;
! 63: {
! 64: struct cfile *fs;
! 65:
! 66: /*
! 67: * The actual PROM driver has already been opened.
! 68: * Just allocate the I/O buffer, etc.
! 69: */
! 70: fs = alloc(sizeof(struct cfile));
! 71: fs->fs_nextblk = 0;
! 72: fs->fs_len = 0;
! 73: fs->fs_ptr = fs->fs_buf;
! 74:
! 75: f->f_fsdata = fs;
! 76: return (0);
! 77: }
! 78:
! 79: int rawfs_close(f)
! 80: struct open_file *f;
! 81: {
! 82: struct cfile *fs;
! 83:
! 84: fs = (struct cfile *) f->f_fsdata;
! 85: f->f_fsdata = (void *)0;
! 86:
! 87: if (fs != (struct cfile *)0)
! 88: free(fs, sizeof(*fs));
! 89:
! 90: return (0);
! 91: }
! 92:
! 93: int rawfs_read(f, start, size, resid)
! 94: struct open_file *f;
! 95: void *start;
! 96: u_int size;
! 97: u_int *resid;
! 98: {
! 99: struct cfile *fs = (struct cfile *)f->f_fsdata;
! 100: char *addr = start;
! 101: int error = 0;
! 102: size_t csize;
! 103:
! 104: while (size != 0) {
! 105:
! 106: if (fs->fs_len == 0)
! 107: if ((error = rawfs_get_block(f)) != 0)
! 108: break;
! 109:
! 110: if (fs->fs_len <= 0)
! 111: break; /* EOF */
! 112:
! 113: csize = size;
! 114: if (csize > fs->fs_len)
! 115: csize = fs->fs_len;
! 116:
! 117: bcopy(fs->fs_ptr, addr, csize);
! 118: fs->fs_ptr += csize;
! 119: fs->fs_len -= csize;
! 120: addr += csize;
! 121: size -= csize;
! 122: }
! 123: if (resid)
! 124: *resid = size;
! 125: return (error);
! 126: }
! 127:
! 128: int rawfs_write(f, start, size, resid)
! 129: struct open_file *f;
! 130: void *start;
! 131: size_t size;
! 132: size_t *resid; /* out */
! 133: {
! 134: return (EROFS);
! 135: }
! 136:
! 137: off_t rawfs_seek(f, offset, where)
! 138: struct open_file *f;
! 139: off_t offset;
! 140: int where;
! 141: {
! 142: return (EFTYPE);
! 143: }
! 144:
! 145: int rawfs_stat(f, sb)
! 146: struct open_file *f;
! 147: struct stat *sb;
! 148: {
! 149: return (EFTYPE);
! 150: }
! 151:
! 152:
! 153: /*
! 154: * Read a block from the underlying stream device
! 155: * (In our case, a tape drive.)
! 156: */
! 157: static int
! 158: rawfs_get_block(f)
! 159: struct open_file *f;
! 160: {
! 161: struct cfile *fs;
! 162: int error, len;
! 163:
! 164: fs = (struct cfile *)f->f_fsdata;
! 165: fs->fs_ptr = fs->fs_buf;
! 166:
! 167: twiddle();
! 168: error = f->f_dev->dv_strategy(f->f_devdata, F_READ,
! 169: fs->fs_nextblk, RAWFS_BSIZE, fs->fs_buf, &len);
! 170:
! 171: if (!error) {
! 172: fs->fs_len = len;
! 173: fs->fs_nextblk += (RAWFS_BSIZE / DEV_BSIZE);
! 174: }
! 175:
! 176: return (error);
! 177: }
! 178:
CVSweb
![[BACK]](/icons/back.gif){kind=icon}
Return to rawfs.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / sys / arch / mvmeppc / stand / libsa