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/cvs/Compress-LZF/LZF.xs
Revision: 1.20
Committed: Fri Jul 7 15:47:10 2006 UTC (17 years, 10 months ago) by root
Branch: MAIN
Changes since 1.19: +82 -16 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #include "EXTERN.h"
2 #include "perl.h"
3 #include "XSUB.h"
4
5 /* try to be compatible with older perls */
6 /* SvPV_nolen() macro first defined in 5.005_55 */
7 /* this is slow, not threadsafe, but works */
8 #include "patchlevel.h"
9 #if (PATCHLEVEL == 4) || ((PATCHLEVEL == 5) && (SUBVERSION < 55))
10 static STRLEN nolen_na;
11 # define SvPV_nolen(sv) SvPV ((sv), nolen_na)
12 #endif
13 #if PATCHLEVEL < 6
14 # define call_sv perl_call_sv
15 #endif
16
17 #include "lzf_c.c"
18 #include "lzf_d.c"
19
20 /* we re-use the storable header for our purposes */
21 #define MAGIC_LO 0
22 #define MAGIC_U 0 /* uncompressed data follows */
23 #define MAGIC_C 1 /* compressed data follows */
24 #define MAGIC_undef 2 /* the special value undef */
25 #define MAGIC_CR 3 /* storable (reference, freeze), compressed */
26 #define MAGIC_R 4 /* storable (reference, freeze) */
27 #define MAGIC_CR_deref 5 /* storable (NO reference, freeze), compressed */
28 #define MAGIC_R_deref 6 /* storable (NO reference, freeze) */
29 #define MAGIC_HI 7 /* room for one higher storable major */
30 /* for historical reasons, MAGIC_undef + MAGIC_R and MAGIC_undef + MAGIC_R_deref are used, too */
31
32 #define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))
33
34 static SV *serializer_package, *serializer_mstore, *serializer_mretrieve;
35 static CV *storable_mstore, *storable_mretrieve;
36
37 #if Size_t_size > 4
38 # define MAX_LENGTH ((Size_t)0x80000000L)
39 #else
40 # define MAX_LENGTH ((Size_t) 0x8000000L)
41 #endif
42
43 static SV *
44 compress_sv (SV *data, char cprepend, int uprepend)
45 {
46 STRLEN usize, csize;
47 char *src = (char *)SvPV (data, usize);
48
49 if (usize)
50 {
51 SV *ret = NEWSV (0, usize + 1);
52 unsigned char *dst;
53 int skip = 0;
54
55 SvPOK_only (ret);
56 dst = (unsigned char *)SvPVX (ret);
57
58 if (cprepend)
59 dst[skip++] = cprepend;
60
61 if (usize <= 0x7f)
62 {
63 dst[skip++] = usize;
64 }
65 else if (usize <= 0x7ff)
66 {
67 dst[skip++] = (( usize >> 6) | 0xc0);
68 dst[skip++] = (( usize & 0x3f) | 0x80);
69 }
70 else if (usize <= 0xffff)
71 {
72 dst[skip++] = (( usize >> 12) | 0xe0);
73 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
74 dst[skip++] = (( usize & 0x3f) | 0x80);
75 }
76 else if (usize <= 0x1fffff)
77 {
78 dst[skip++] = (( usize >> 18) | 0xf0);
79 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
80 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
81 dst[skip++] = (( usize & 0x3f) | 0x80);
82 }
83 else if (usize <= 0x3ffffff)
84 {
85 dst[skip++] = (( usize >> 24) | 0xf8);
86 dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
87 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
88 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
89 dst[skip++] = (( usize & 0x3f) | 0x80);
90 }
91 else if (usize <= 0x7fffffff)
92 {
93 dst[skip++] = (( usize >> 30) | 0xfc);
94 dst[skip++] = (((usize >> 24) & 0x3f) | 0x80);
95 dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
96 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
97 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
98 dst[skip++] = (( usize & 0x3f) | 0x80);
99 }
100 else
101 croak ("compress can only compress up to %ld bytes", 0x7fffffffL);
102
103 /* 11 bytes is the smallest compressible string */
104 csize = usize < 11 ? 0 :
105 lzf_compress (src, usize,
106 dst + skip,
107 usize - skip);
108
109 if (csize)
110 {
111 SvCUR_set (ret, csize + skip);
112 }
113 else if (uprepend < 0)
114 {
115 SvREFCNT_dec (ret);
116 ret = SvREFCNT_inc (data);
117 }
118 else
119 {
120 *dst++ = uprepend;
121
122 Move ((void *)src, (void *)dst, usize, unsigned char);
123
124 SvCUR_set (ret, usize + 1);
125 }
126
127 return ret;
128 }
129 else
130 return newSVpv ("", 0);
131 }
132
133 static SV *
134 decompress_sv (SV *data, int skip)
135 {
136 STRLEN usize, csize;
137 unsigned char *src = (unsigned char *)SvPV (data, csize) + skip;
138
139 if (csize)
140 {
141 void *dst;
142 SV *ret;
143
144 csize -= skip;
145
146 if (src[0])
147 {
148 if (!(src[0] & 0x80))
149 {
150 csize -= 1;
151 usize = *src++ & 0xff;
152 }
153 else if (!(src[0] & 0x20))
154 {
155 csize -= 2;
156 usize = *src++ & 0x1f;
157 usize = (usize << 6) | (*src++ & 0x3f);
158 }
159 else if (!(src[0] & 0x10))
160 {
161 csize -= 3;
162 usize = *src++ & 0x0f;
163 usize = (usize << 6) | (*src++ & 0x3f);
164 usize = (usize << 6) | (*src++ & 0x3f);
165 }
166 else if (!(src[0] & 0x08))
167 {
168 csize -= 4;
169 usize = *src++ & 0x07;
170 usize = (usize << 6) | (*src++ & 0x3f);
171 usize = (usize << 6) | (*src++ & 0x3f);
172 usize = (usize << 6) | (*src++ & 0x3f);
173 }
174 else if (!(src[0] & 0x04))
175 {
176 csize -= 5;
177 usize = *src++ & 0x03;
178 usize = (usize << 6) | (*src++ & 0x3f);
179 usize = (usize << 6) | (*src++ & 0x3f);
180 usize = (usize << 6) | (*src++ & 0x3f);
181 usize = (usize << 6) | (*src++ & 0x3f);
182 }
183 else if (!(src[0] & 0x02))
184 {
185 csize -= 6;
186 usize = *src++ & 0x01;
187 usize = (usize << 6) | (*src++ & 0x3f);
188 usize = (usize << 6) | (*src++ & 0x3f);
189 usize = (usize << 6) | (*src++ & 0x3f);
190 usize = (usize << 6) | (*src++ & 0x3f);
191 usize = (usize << 6) | (*src++ & 0x3f);
192 }
193 else
194 croak ("compressed data corrupted (invalid length)");
195
196 ret = NEWSV (0, usize);
197 SvPOK_only (ret);
198 dst = SvPVX (ret);
199
200 if (lzf_decompress (src, csize, dst, usize) != usize)
201 croak ("compressed data corrupted (size mismatch)", csize, skip, usize);
202 }
203 else
204 {
205 usize = csize - 1;
206 ret = NEWSV (0, usize);
207 SvPOK_only (ret);
208
209 Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
210 }
211
212 SvCUR_set (ret, usize);
213
214 return ret;
215 }
216 else
217 return newSVpvn ("", 0);
218 }
219
220 static void
221 need_storable(void)
222 {
223 #if PATCHLEVEL < 6
224 char req[8192];
225 sprintf (req, "require %s;", SvPV_nolen (serializer_package));
226 perl_eval_pv (req, 1);
227 #else
228 load_module (PERL_LOADMOD_NOIMPORT, serializer_package, Nullsv);
229 #endif
230
231 storable_mstore = GvCV (gv_fetchpv (SvPV_nolen (serializer_mstore ), TRUE, SVt_PVCV));
232 storable_mretrieve = GvCV (gv_fetchpv (SvPV_nolen (serializer_mretrieve), TRUE, SVt_PVCV));
233 }
234
235 MODULE = Compress::LZF PACKAGE = Compress::LZF
236
237 BOOT:
238 serializer_package = newSVpv ("Storable", 0);
239 serializer_mstore = newSVpv ("Storable::net_mstore", 0);
240 serializer_mretrieve = newSVpv ("Storable::mretrieve", 0);
241
242 void
243 set_serializer(package, mstore, mretrieve)
244 SV * package
245 SV * mstore
246 SV * mretrieve
247 PROTOTYPE: $$$
248 PPCODE:
249 SvSetSV (serializer_package , package );
250 SvSetSV (serializer_mstore , mstore );
251 SvSetSV (serializer_mretrieve, mretrieve);
252 storable_mstore =
253 storable_mretrieve = 0;
254
255 void
256 compress(data)
257 SV * data
258 PROTOTYPE: $
259 PPCODE:
260 XPUSHs (sv_2mortal (compress_sv (data, 0, MAGIC_U)));
261
262 void
263 decompress(data)
264 SV * data
265 PROTOTYPE: $
266 PPCODE:
267 XPUSHs (sv_2mortal (decompress_sv (data, 0)));
268
269 void
270 sfreeze(sv)
271 SV * sv
272 ALIAS:
273 sfreeze_cr = 1
274 sfreeze_c = 2
275 PROTOTYPE: $
276 PPCODE:
277
278 SvGETMAGIC (sv);
279
280 if (!SvOK (sv))
281 XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
282 else if (SvROK (sv)
283 || (SvTYPE(sv) != SVt_IV
284 && SvTYPE(sv) != SVt_NV
285 && SvTYPE(sv) != SVt_PV
286 && SvTYPE(sv) != SVt_PVIV
287 && SvTYPE(sv) != SVt_PVNV
288 && SvTYPE(sv) != SVt_PVMG)) /* mstore */
289 {
290 int deref = !SvROK (sv);
291
292 if (!storable_mstore)
293 need_storable ();
294
295 if (deref)
296 sv = newRV_noinc (sv);
297
298 PUSHMARK (SP);
299 XPUSHs (sv);
300 PUTBACK;
301
302 if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
303 croak ("Storable::mstore didn't return a single scalar");
304
305 SPAGAIN;
306
307 sv = POPs;
308
309 if (SvPVX (sv)[0] == MAGIC_R)
310 {
311 if (deref)
312 SvPVX (sv)[0] = MAGIC_R_deref;
313 }
314 else
315 {
316 char pfx[2];
317
318 pfx[0] = MAGIC_undef;
319 pfx[1] = deref ? MAGIC_R_deref : MAGIC_R;
320
321 sv_insert (sv, 0, 0, pfx, 2);
322 }
323
324 if (ix) /* compress */
325 sv = sv_2mortal (compress_sv (sv, deref ? MAGIC_CR_deref : MAGIC_CR, -1));
326
327 XPUSHs (sv);
328 }
329 else if (SvPOKp (sv) && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
330 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, MAGIC_U))); /* need to prefix only */
331 else if (ix == 2) /* compress always */
332 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, -1)));
333 else if (SvNIOK (sv)) /* don't compress */
334 {
335 STRLEN len;
336 char *s = SvPV (sv, len);
337 XPUSHs (sv_2mortal (newSVpvn (s, len)));
338 }
339 else /* don't compress */
340 XPUSHs (sv_2mortal (newSVsv (sv)));
341
342 void
343 sthaw(sv)
344 SV * sv
345 PROTOTYPE: $
346 PPCODE:
347 {
348 STRLEN svlen;
349 int deref = 0;
350
351 SvGETMAGIC (sv);
352 if (SvPOK (sv) && IN_RANGE (SvPV (sv, svlen)[0], MAGIC_LO, MAGIC_HI))
353 {
354 redo:
355
356 switch (SvPVX (sv)[0])
357 {
358 case MAGIC_undef:
359 if (svlen <= 1)
360 XPUSHs (sv_2mortal (NEWSV (0, 0)));
361 else
362 {
363 if (SvPVX (sv)[1] == MAGIC_R_deref)
364 deref = 1;
365 else if (SvPVX (sv)[1] != MAGIC_R)
366 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
367
368 sv_chop (sv, SvPVX (sv) + 2);
369
370 if (!storable_mstore)
371 need_storable ();
372
373 PUSHMARK (SP);
374 XPUSHs (sv);
375 PUTBACK;
376
377 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
378 croak ("Storable::mstore didn't return a single scalar");
379
380 SPAGAIN;
381
382 if (deref)
383 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
384 else
385 SETs (sv_2mortal (newSVsv (TOPs)));
386 }
387 break;
388
389 case MAGIC_U:
390 XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
391 break;
392
393 case MAGIC_C:
394 XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
395 break;
396
397 case MAGIC_R_deref:
398 deref = 1;
399 SvPVX (sv)[0] = MAGIC_R;
400 goto handle_MAGIC_R;
401
402 case MAGIC_CR_deref:
403 deref = 1;
404 case MAGIC_CR:
405 sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
406 if (deref)
407 if (SvPVX (sv)[0] == MAGIC_R_deref)
408 SvPVX (sv)[0] = MAGIC_R;
409
410 goto redo;
411
412 case MAGIC_R:
413 handle_MAGIC_R:
414 if (!storable_mstore)
415 need_storable ();
416
417 PUSHMARK (SP);
418 XPUSHs (sv);
419 PUTBACK;
420
421 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
422 croak ("Storable::mstore didn't return a single scalar");
423
424 SPAGAIN;
425
426 if (deref)
427 {
428 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
429
430 if (SvPVX (sv)[0] == MAGIC_R)
431 SvPVX (sv)[0] = MAGIC_R_deref;
432 }
433 else
434 SETs (sv_2mortal (newSVsv (TOPs)));
435
436 break;
437
438 default:
439 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
440 }
441 }
442 else
443 XPUSHs (sv_2mortal (newSVsv (sv)));
444 }
445