source: buchla-68k/libcio/write.c

Last change on this file was 8973acd, checked in by Thomas Lopatic <thomas@…>, 7 years ago

No more warnings in libcio.
  • Property mode set to 100644
File size: 5.1 KB
Line 
1/*
2 ============================================================================
3 write.c -- write() and friends
4 Version 17 -- 1987-10-27 -- D.N. Lynx Crowe
5 ============================================================================
6*/
7
8#define DEBUGIT 0
9
10#include "ram.h"
11
12/* write routine dispatch table */
13
14static int16_t (*wr_tab[])(io_arg arg, void *buff, int16_t len) = {
15
16 _badfio, /* 0 - invalid entry */
17 _filewr, /* 1 - disk file */
18 _conwr /* 2 - console device */
19};
20
21/*
22 ============================================================================
23 _putsec(fp, buf, len) -- write 'len' bytes from 'buf' on file 'fp'
24 ============================================================================
25*/
26
27int16_t _putsec(struct fcb *fp, void *buf, int16_t len)
28{
29#if DEBUGIT
30 if (fsdebug)
31 printf("_putsec($%08lX, $%08lx, %d): initial curlsn=%ld\n",
32 fp, buf, len, fp->curlsn);
33#endif
34
35 if ((errno = ReadRN(fp, Wrkbuf)) EQ 1) { /* try to read sector */
36
37#if DEBUGIT
38 if (fsdebug)
39 printf("_putsec(): ReadRN saw EOF at curlsn=%ld, asects=%ld\n",
40 fp->curlsn, fp->asects);
41#endif
42
43 errno = 0; /* we're at EOF */
44 memset(Wrkbuf, 0x1A, BPSEC); /* pad end of sector */
45
46 } else if (errno)
47 return(FAILURE);
48
49 memcpy(Wrkbuf + fp->offset, buf, len); /* move in the new data */
50
51 if ((errno = WriteRN(fp, Wrkbuf)) NE 0) { /* write the sector */
52
53#if DEBUGIT
54 if (fsdebug)
55 printf("_putsec(): WriteRN() FAILED (%d) - curlsn=%ld\n",
56 errno, fp->curlsn);
57#endif
58
59 return(FAILURE);
60 }
61
62 if ((fp->offset = (fp->offset + len) & (BPSEC - 1)) EQ 0) {
63
64 ++fp->curlsn; /* update file position */
65
66 if (_seek(fp) < 0) {
67
68#if DEBUGIT
69 if (fsdebug)
70 printf("_putsec(): _seek() failed - curlsn=%ld, asects=%ld\n",
71 fp->curlsn, fp->asects);
72#endif
73
74 return(FAILURE);
75 }
76 }
77
78#if DEBUGIT
79 if (fsdebug)
80 printf("_putsec(): final curlsn=%ld, offset=%d, len=%d\n",
81 fp->curlsn, fp->offset, len);
82#endif
83
84 return(SUCCESS);
85}
86
87/*
88 ============================================================================
89 _filewr(fp, buffer, len) -- write 'len' bytes on file 'fp'
90 from 'buffer'.
91 ============================================================================
92*/
93
94int16_t _filewr(io_arg arg, void *buffer, int16_t len)
95{
96 struct fcb *fp;
97 int8_t *buffer8;
98 register int16_t j, k, l;
99 int16_t clustr;
100 register int32_t cpos;
101
102 fp = (struct fcb *)arg;
103 buffer8 = buffer;
104
105 cpos = fp->offset + ((int32_t)fp->curlsn << FILESHFT); /* get position */
106
107 if (fp->de.bclust EQ 0) { /* see if we need to allocate */
108
109#if DEBUGIT
110 if (fsdebug)
111 if (cpos)
112 printf("_filewr(): ERROR - bclust EQ 0 and curpos (%ld) NE 0\n",
113 cpos);
114#endif
115
116 if (0 EQ (clustr = _newcls())) { /* allocate a cluster */
117
118 errno = EIO;
119 return(len);
120 }
121
122 fp->de.bclust = micon16((uint16_t)clustr); /* update FCB */
123 _ptcl12(_thefat, clustr, 0x0FF8); /* update FAT */
124 _fatmod = TRUE;
125 fp->curdsn = _cl2lsn(_thebpb, clustr); /* set curdsn */
126 fp->curcls = clustr;
127 fp->clsec = 0;
128 fp->asects = _thebpb->clsiz;
129#if DEBUGIT
130 if (fsdebug) {
131
132 printf("_filewr(): allocated initial cluster=%d, asects=%ld\n",
133 clustr, fp->asects);
134 SnapFCB(fp);
135 }
136#endif
137 }
138
139 l = 0; /* zero the length-written counter */
140
141#if DEBUGIT
142 if (fsdebug)
143 printf("_filewr(): init pos=%ld, len=%u, curcls=%u, offset=%u\n",
144 cpos, len, fp->curcls, fp->offset);
145#endif
146
147 if (fp->offset) { /* see if we have a partial sector to fill */
148
149 if ((l = (BPSEC - fp->offset)) > len)
150 l = len;
151
152 if (_putsec(fp, buffer8, l)) /* fill up the sector */
153 return(-1);
154 }
155
156 if ((k = (len - l) / BPSEC)) { /* write out any full sectors */
157
158 if ((j = blkwr(fp, buffer8 + l, k)) NE 0) {
159
160 l += (k - j) * BPSEC; /* update amount written */
161
162 if ((cpos + l) > fp->curlen) /* udpate file length */
163 fp->de.flen = micon32((uint32_t)(fp->curlen = cpos + l));
164
165#if DEBUGIT
166 if (fsdebug)
167 printf("_filewr(): ERROR - curlen=%ld, curlsn=%ld, curdsn=%ld\n",
168 fp->curlen, fp->curlsn, fp->curdsn);
169#endif
170
171 return(l);
172 }
173
174 l += k * BPSEC; /* update amount written */
175 }
176
177 if (l < len) { /* write out partial sector at end */
178
179 if (_putsec(fp, buffer8 + l, len - l)) {
180
181 if ((cpos + l) > fp->curlen) /* update file length */
182 fp->de.flen = micon32((uint32_t)(fp->curlen = cpos + l));
183
184#if DEBUGIT
185 if (fsdebug)
186 printf("_filewr(): ERROR - curlen=%ld, curlsn=%ld, curdsn=%ld\n",
187 fp->curlen, fp->curlsn, fp->curdsn);
188#endif
189
190 return(l);
191 }
192 }
193
194 if ((cpos + len) > fp->curlen) /* update file length */
195 fp->de.flen = micon32((uint32_t)(fp->curlen = cpos + len));
196
197#if DEBUGIT
198 if (fsdebug)
199 printf("_filewr(): final curlen=%ld, flen=$%08lX, curlsn=%ld, curdsn=%ld\n",
200 fp->curlen, fp->de.flen, fp->curlsn, fp->curdsn);
201#endif
202
203 return(len);
204}
205
206/*
207 ============================================================================
208 write(fd, buff, len) -- write 'len' bytes from 'buff' on file 'fd'
209 ============================================================================
210*/
211
212int16_t write(int16_t fd, void *buff, int16_t len)
213{
214 register struct channel *chp;
215
216 if ((fd < 0) OR (fd > MAXCHAN)) {
217
218 errno = EBADF;
219 return(-1);
220 }
221
222 chp = &chantab[fd];
223
224 return((*wr_tab[chp->c_write])(chp->c_arg, buff, len));
225}
226
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