projects / unix-history / blame
| Commit | Line | Data |
|---|---|---|
| f70ab843 RH |
1 | /* |
| 2 | * Copyright (c) 1982 Regents of the University of California | |
| 3 | */ | |
| 4 | #ifndef lint | |
| 5 | static char sccsid[] = "@(#)asio.c 4.4 %G%"; | |
| 6 | #endif not lint | |
| 7 | ||
| 8ad3c13d | 8 | #include <stdio.h> |
| 8ad3c13d BJ |
9 | #include "as.h" |
| 10 | /* | |
| 11 | * Block I/O routines for logical I/O concurrently in | |
| 12 | * more than one place in the same file. | |
| 13 | */ | |
| 14 | int biofd; /* file descriptor for block I/O file */ | |
| 15 | off_t boffset; /* physical position in logical file */ | |
| 16 | BFILE *biobufs; /* the block I/O buffers */ | |
| 17 | ||
| 18 | #define error(severity, message) \ | |
| 19 | {yyerror(message); if (severity) delexit();} | |
| 20 | ||
| 21 | Flushfield(n) | |
| 22 | register int n; | |
| 23 | { | |
| 24 | while (n>0) { | |
| 25 | outb(bitfield); | |
| 26 | bitfield >>= 8; | |
| 27 | n -= 8; | |
| 28 | } | |
| 29 | bitoff=0; | |
| 30 | bitfield=0; | |
| 31 | } | |
| 32 | ||
| 8ad3c13d | 33 | /* |
| bef6dadc | 34 | * Block I/O Routines |
| 8ad3c13d | 35 | */ |
| 8ad3c13d BJ |
36 | bopen(bp, off) |
| 37 | struct biobuf *bp; | |
| 38 | off_t off; | |
| 39 | { | |
| 40 | ||
| 41 | bp->b_ptr = bp->b_buf; | |
| 42 | bp->b_nleft = BUFSIZ - off % BUFSIZ; | |
| 43 | bp->b_off = off; | |
| 44 | bp->b_link = biobufs; | |
| 45 | biobufs = bp; | |
| 46 | } | |
| 47 | ||
| 48 | int bwrerror; | |
| 49 | ||
| 50 | bwrite(p, cnt, bp) | |
| 51 | register char *p; | |
| 52 | register int cnt; | |
| 53 | register struct biobuf *bp; | |
| 54 | { | |
| 55 | register int put; | |
| 56 | register char *to; | |
| 57 | ||
| 58 | top: | |
| 59 | if (cnt == 0) | |
| 60 | return; | |
| 61 | if (bp->b_nleft) { | |
| 62 | put = bp->b_nleft; | |
| 63 | if (put > cnt) | |
| 64 | put = cnt; | |
| 65 | bp->b_nleft -= put; | |
| 66 | to = bp->b_ptr; | |
| f70ab843 RH |
67 | #ifdef lint |
| 68 | *to = *to; | |
| 69 | #endif lint | |
| 8ad3c13d BJ |
70 | asm("movc3 r8,(r11),(r7)"); |
| 71 | bp->b_ptr += put; | |
| 72 | p += put; | |
| 73 | cnt -= put; | |
| 74 | goto top; | |
| 75 | } | |
| 76 | if (cnt >= BUFSIZ) { | |
| 77 | if (bp->b_ptr != bp->b_buf) | |
| 78 | bflush1(bp); | |
| 79 | put = cnt - cnt % BUFSIZ; | |
| 80 | if (boffset != bp->b_off) | |
| f70ab843 | 81 | (void)lseek(biofd, (long)bp->b_off, 0); |
| 8ad3c13d BJ |
82 | if (write(biofd, p, put) != put) { |
| 83 | bwrerror = 1; | |
| 84 | error(1, "Output write error"); | |
| 85 | } | |
| 86 | bp->b_off += put; | |
| 87 | boffset = bp->b_off; | |
| 88 | p += put; | |
| 89 | cnt -= put; | |
| 90 | goto top; | |
| 91 | } | |
| 92 | bflush1(bp); | |
| 93 | goto top; | |
| 94 | } | |
| 95 | ||
| 96 | bflush() | |
| 97 | { | |
| 98 | register struct biobuf *bp; | |
| 99 | ||
| 100 | if (bwrerror) | |
| 101 | return; | |
| 102 | for (bp = biobufs; bp; bp = bp->b_link) | |
| 103 | bflush1(bp); | |
| 104 | } | |
| 105 | ||
| 106 | bflush1(bp) | |
| 107 | register struct biobuf *bp; | |
| 108 | { | |
| 109 | register int cnt = bp->b_ptr - bp->b_buf; | |
| 110 | ||
| 111 | if (cnt == 0) | |
| 112 | return; | |
| 113 | if (boffset != bp->b_off) | |
| f70ab843 | 114 | (void)lseek(biofd, (long)bp->b_off, 0); |
| 8ad3c13d BJ |
115 | if (write(biofd, bp->b_buf, cnt) != cnt) { |
| 116 | bwrerror = 1; | |
| 117 | error(1, "Output write error"); | |
| 118 | } | |
| 119 | bp->b_off += cnt; | |
| 120 | boffset = bp->b_off; | |
| 121 | bp->b_ptr = bp->b_buf; | |
| 122 | bp->b_nleft = BUFSIZ; | |
| 123 | } | |
| 124 | ||
| 125 | bflushc(bp, c) | |
| 126 | register struct biobuf *bp; | |
| 127 | char c; | |
| 128 | { | |
| 8ad3c13d BJ |
129 | bflush1(bp); |
| 130 | bputc(c, bp); | |
| 131 | } |