3 * Handle ArcFS format archives
5 * Author: Andrew Brooks, arb@comp.lancs.ac.uk
7 * $Header: arcfs.c 1.5 95/08/01 $
9 * Revision 1.5 95/08/01 xx:xx:xx BB
10 * Fixes for Borland C/C++
11 * Removed use of floating point routines.
13 * Revision 1.4 95/01/06 11:58:45 arb
16 * Revision 1.3 94/12/12 17:25:25 arb
17 * Fixes for writesize.
19 * Revision 1.2 94/10/26 15:06:35 arb
20 * Fixed date and time conversion.
22 * Revision 1.1 94/02/28 21:41:23 arb
23 * Fixed header, fixed include ordering, fixed directory check,
24 * added seek to start of compressed data, fixed maxbits, ...
25 * ie. got the thing working at last!
27 * Revision 1.0 93/08/20 12:40:15 arb
37 #include <sys/types.h>
40 #if defined(RISCOS) || defined(__MSDOS__)
43 #endif /* RISCOS || __MSDOS__ */
55 * Public flag to indicate whether the current archive is ArcFS format
61 * Public number of compression bits, used in compress.c
63 int arcfs_maxbits
= 0;
67 * Public size of file being extracted, used in io.c, crc.c
74 * ArcFS header list element
78 struct arcfs_header_s
*next
;
86 typedef struct arcfs_header_s
*arcfs_header
;
94 #define AFS_STORE 0x82
96 #define AFS_CRUNCH 0x88
97 #define AFS_COMPRESS 0xFF
103 static int arcfs_initialised
= 0;
104 static arcfs_header header_list
= NULL
;
105 static arcfs_header header_ptr
= NULL
;
109 * Convert RISC OS time to UNIX time.
110 * RISC OS time is five bytes of centiseconds since 1900.
111 * UNIX time is seconds since 1970.
112 * MSB of RISC OS time is LSB of `load' plus `exec'.
115 /* BB added extra prototype for Borland C/C++ */
118 rotm(Word load
, Word exec
)
123 high
= (load
& 0xff) - 0x33l
;
124 low
= exec
- 0x6e996a00l
;
125 /* BB changed constant in next line to long */
126 /* cast to Word, then time_t as date stamps will all be 32 bits and time_t
127 * might be 64 bits */
128 t
= (time_t)(Word
)(high
* 42949673L + low
/ 100L);
129 return (localtime(&t
));
134 * Convert RISC OS time to SPARK time
137 /* BB added extra prototype for Borland C/C++ */
140 arcfs_fixtime(Header
*hdr
)
142 /* BB next line commented out, variable ti never used */
146 /* Convert to UNIX time first (as it is easy) */
147 tim
= rotm(hdr
->load
, hdr
->exec
);
149 /* Convert UNIX time to SPARK time */
150 hdr
->date
= (tim
->tm_year
- 80) << 9;
151 hdr
->date
|= (tim
->tm_mon
+ 1) << 5;
152 hdr
->date
|= (tim
->tm_mday
);
153 hdr
->time
= (tim
->tm_hour
) << 11;
154 hdr
->time
|= (tim
->tm_min
) << 5;
155 hdr
->time
|= (tim
->tm_sec
);
163 arcfs_read_header(FILE *ifp
)
165 static Header null_header
;
166 static Word data_start
;
167 Word header_length
= 0;
171 Byte info_byte
, name
[12];
172 Word length
, load
, exec
, attr
, complen
, info_word
;
173 arcfs_header header_prev
= NULL
;
176 /* Return next header from list */
177 if (arcfs_initialised
)
179 /* If end of list return an empty header structure to indicate EOF */
180 if (header_ptr
== NULL
)
181 return (&null_header
);
183 /* Return next header in list */
184 header
= header_ptr
->header
;
185 /* Seek to start of compressed data */
186 if ((!header_ptr
->is_dir
)
187 && (fseek(ifp
, (long) header_ptr
->seek
, SEEK_SET
)))
189 printf("Cannot seek compressed data in this file\n");
190 return (&null_header
);
192 /* Set up number of compression bits */
193 arcfs_maxbits
= header_ptr
->maxbits
;
194 /*if (header_ptr->is_dir) header = &null_header; */
195 header_ptr
= header_ptr
->next
;
199 /* Header list not constructed yet, so read all headers from file */
200 arcfs_initialised
= 1;
201 memset((char *) &null_header
, '\0', sizeof(null_header
));
202 null_header
.comptype
= 0;
203 header_length
= read_word(ifp
);
204 data_start
= read_word(ifp
);
205 if ((version
= read_word(ifp
)) > 40)
207 /* BB removed floating point routines from next line
208 This saves linking the floating point routines under DOS
209 which yields quite a reduction in executable size.
210 And it removes the need to have the FPE present under RISC OS. */
211 /* printf("Archive created by a newer version of ArcFS (%.2f)\n",((float)version)/100); */
212 printf("Archive created by a newer version of ArcFS (%d.%02d)\n",
213 version
/ 100, version
% 100);
214 return (&null_header
);
216 read_word(ifp
); /* read/write version */
217 if ((version
= read_word(ifp
)) > 0)
219 printf("Archive format %d not understood\n", version
);
220 return (&null_header
);
222 for (i
= 0; i
< 17; i
++)
223 read_word(ifp
); /* reserved */
225 /* Read list of headers */
226 for (i
= 0; i
< header_length
/ 36; i
++)
228 /* Create list item */
229 header
= (Header
*) malloc(sizeof(Header
));
230 header_ptr
= (arcfs_header
) malloc(sizeof(struct arcfs_header_s
));
231 if ((header
== NULL
) || (header_ptr
== NULL
))
233 printf("Out of memory\n");
234 return (&null_header
);
237 /* Read ArcFS file header */
238 info_byte
= read_byte(ifp
);
239 for (j
= 0; j
< 11; j
++)
241 name
[j
] = read_byte(ifp
);
242 if (name
[j
] == PATHSEP
)
244 if (name
[j
] < ' ' || name
[j
] > '~')
248 length
= read_word(ifp
);
249 load
= read_word(ifp
);
250 exec
= read_word(ifp
);
251 attr
= read_word(ifp
);
252 complen
= read_word(ifp
);
253 info_word
= read_word(ifp
);
255 /* Examine, and create nspark header */
256 if (info_byte
== AFS_DELETED
)
262 /* BB changed next line for Borland C/C++ 4 */
263 /* header_ptr->is_dir = (info_word >> 31); */
265 header_ptr
->is_dir
= (Halfword
) (info_word
>> 31);
267 header_ptr
->is_dir
= (info_word
>> 31);
269 header_ptr
->info_byte
= info_byte
;
270 header_ptr
->info_word
= info_word
;
271 /* BB changed next line for Borland C/C++ 4 */
272 /* header_ptr->maxbits = (attr & 0xff00) >> 8; */
274 header_ptr
->maxbits
= (Halfword
) (attr
& 0xff00) >> 8;
276 header_ptr
->maxbits
= (attr
& 0xff00) >> 8;
278 /* BB changed constant in next line to long. */
279 header_ptr
->seek
= (info_word
& 0x7fffffffL
) + data_start
;
280 header
->comptype
= info_byte
;
281 strcpy(header
->name
, (char *) name
);
282 header
->complen
= complen
;
285 header
->crc
= (Halfword
) (attr
>> 16);
286 header
->origlen
= length
;
289 header
->attr
= attr
& 0xff;
291 arcfs_fixtime(header
);
293 if (info_byte
== AFS_ENDDIR
)
295 /* Just return comptype == 0 */
296 *header
= null_header
;
297 header_ptr
->is_dir
= 0;
298 header_ptr
->seek
= 0;
301 /* If it is an ArcFS directory then convert to a Spark directory */
302 if (header_ptr
->is_dir
)
304 /* Make sure filetype is DDC */
305 header
->comptype
= CT_NOTCOMP2
;
306 /* BB changed constant in next line to long. */
307 header
->load
= 0xfffddcffL
;
310 /* Add list item to list */
311 /* Doing it here ensures that deleted items are not added */
312 header_ptr
->header
= header
;
313 if (header_list
== NULL
)
314 header_list
= header_ptr
;
316 header_prev
->next
= header_ptr
;
317 header_prev
= header_ptr
;
319 print_header(header
);
323 /* Return first element */
324 header_ptr
= header_list
;
325 header
= header_ptr
->header
;
326 /* Seek to start of data for first element */
327 if ((!header_ptr
->is_dir
)
328 && (fseek(ifp
, (long) header_ptr
->seek
, SEEK_SET
)))
330 printf("Cannot seek compressed data in this file\n");
331 return (&null_header
);
333 /* Set up number of compression bits */
334 arcfs_maxbits
= header_ptr
->maxbits
;
335 /*if (header_ptr->is_dir) header = &null_header; */
336 header_ptr
= header_ptr
->next
;