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/cvs/Compress-LZF/LZF.xs
Revision: 1.22
Committed: Wed Sep 27 19:01:48 2006 UTC (17 years, 7 months ago) by root
Branch: MAIN
Changes since 1.21: +4 -1 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) && csize >= 1)
149 {
150 csize -= 1;
151 usize = *src++ & 0xff;
152 }
153 else if (!(src[0] & 0x20) && csize >= 2)
154 {
155 csize -= 2;
156 usize = *src++ & 0x1f;
157 usize = (usize << 6) | (*src++ & 0x3f);
158 }
159 else if (!(src[0] & 0x10) && csize >= 3)
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) && csize >= 4)
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) && csize >= 5)
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) && csize >= 6)
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 if (!usize)
197 croak ("compressed data corrupted (invalid length)");
198
199 ret = NEWSV (0, usize);
200 SvPOK_only (ret);
201 dst = SvPVX (ret);
202
203 if (lzf_decompress (src, csize, dst, usize) != usize)
204 {
205 SvREFCNT_dec (ret);
206 croak ("compressed data corrupted (size mismatch)", csize, skip, usize);
207 }
208 }
209 else
210 {
211 usize = csize - 1;
212 ret = NEWSV (0, usize | 1);
213 SvPOK_only (ret);
214
215 Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
216 }
217
218 SvCUR_set (ret, usize);
219
220 return ret;
221 }
222 else
223 return newSVpvn ("", 0);
224 }
225
226 static void
227 need_storable(void)
228 {
229 #if PATCHLEVEL < 6
230 char req[8192];
231 sprintf (req, "require %s;", SvPV_nolen (serializer_package));
232 perl_eval_pv (req, 1);
233 #else
234 load_module (PERL_LOADMOD_NOIMPORT, serializer_package, Nullsv);
235 #endif
236
237 storable_mstore = GvCV (gv_fetchpv (SvPV_nolen (serializer_mstore ), TRUE, SVt_PVCV));
238 storable_mretrieve = GvCV (gv_fetchpv (SvPV_nolen (serializer_mretrieve), TRUE, SVt_PVCV));
239 }
240
241 MODULE = Compress::LZF PACKAGE = Compress::LZF
242
243 BOOT:
244 serializer_package = newSVpv ("Storable", 0);
245 serializer_mstore = newSVpv ("Storable::net_mstore", 0);
246 serializer_mretrieve = newSVpv ("Storable::mretrieve", 0);
247
248 void
249 set_serializer(package, mstore, mretrieve)
250 SV * package
251 SV * mstore
252 SV * mretrieve
253 PROTOTYPE: $$$
254 PPCODE:
255 SvSetSV (serializer_package , package );
256 SvSetSV (serializer_mstore , mstore );
257 SvSetSV (serializer_mretrieve, mretrieve);
258 storable_mstore =
259 storable_mretrieve = 0;
260
261 void
262 compress(data)
263 SV * data
264 PROTOTYPE: $
265 PPCODE:
266 XPUSHs (sv_2mortal (compress_sv (data, 0, MAGIC_U)));
267
268 void
269 decompress(data)
270 SV * data
271 PROTOTYPE: $
272 PPCODE:
273 XPUSHs (sv_2mortal (decompress_sv (data, 0)));
274
275 void
276 sfreeze(sv)
277 SV * sv
278 ALIAS:
279 sfreeze_cr = 1
280 sfreeze_c = 2
281 PROTOTYPE: $
282 PPCODE:
283
284 SvGETMAGIC (sv);
285
286 if (!SvOK (sv))
287 XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
288 else if (SvROK (sv)
289 || (SvTYPE(sv) != SVt_IV
290 && SvTYPE(sv) != SVt_NV
291 && SvTYPE(sv) != SVt_PV
292 && SvTYPE(sv) != SVt_PVIV
293 && SvTYPE(sv) != SVt_PVNV
294 && SvTYPE(sv) != SVt_PVMG)) /* mstore */
295 {
296 int deref = !SvROK (sv);
297
298 if (!storable_mstore)
299 need_storable ();
300
301 if (deref)
302 sv = newRV_noinc (sv);
303
304 PUSHMARK (SP);
305 XPUSHs (sv);
306 PUTBACK;
307
308 if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
309 croak ("Storable::mstore didn't return a single scalar");
310
311 SPAGAIN;
312
313 sv = POPs;
314
315 if (SvPVX (sv)[0] == MAGIC_R)
316 {
317 if (deref)
318 SvPVX (sv)[0] = MAGIC_R_deref;
319 }
320 else
321 {
322 char pfx[2];
323
324 pfx[0] = MAGIC_undef;
325 pfx[1] = deref ? MAGIC_R_deref : MAGIC_R;
326
327 sv_insert (sv, 0, 0, pfx, 2);
328 }
329
330 if (ix) /* compress */
331 sv = sv_2mortal (compress_sv (sv, deref ? MAGIC_CR_deref : MAGIC_CR, -1));
332
333 XPUSHs (sv);
334 }
335 else if (SvPOKp (sv) && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
336 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, MAGIC_U))); /* need to prefix only */
337 else if (ix == 2) /* compress always */
338 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, -1)));
339 else if (SvNIOK (sv)) /* don't compress */
340 {
341 STRLEN len;
342 char *s = SvPV (sv, len);
343 XPUSHs (sv_2mortal (newSVpvn (s, len)));
344 }
345 else /* don't compress */
346 XPUSHs (sv_2mortal (newSVsv (sv)));
347
348 void
349 sthaw(sv)
350 SV * sv
351 PROTOTYPE: $
352 PPCODE:
353 {
354 STRLEN svlen;
355 int deref = 0;
356
357 SvGETMAGIC (sv);
358 if (SvPOK (sv) && IN_RANGE (SvPV (sv, svlen)[0], MAGIC_LO, MAGIC_HI))
359 {
360 redo:
361
362 switch (SvPVX (sv)[0])
363 {
364 case MAGIC_undef:
365 if (svlen <= 1)
366 XPUSHs (sv_2mortal (NEWSV (0, 0)));
367 else
368 {
369 if (SvPVX (sv)[1] == MAGIC_R_deref)
370 deref = 1;
371 else if (SvPVX (sv)[1] != MAGIC_R)
372 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
373
374 sv_chop (sv, SvPVX (sv) + 2);
375
376 if (!storable_mstore)
377 need_storable ();
378
379 PUSHMARK (SP);
380 XPUSHs (sv);
381 PUTBACK;
382
383 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
384 croak ("Storable::mstore didn't return a single scalar");
385
386 SPAGAIN;
387
388 if (deref)
389 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
390 else
391 SETs (sv_2mortal (newSVsv (TOPs)));
392 }
393 break;
394
395 case MAGIC_U:
396 XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
397 break;
398
399 case MAGIC_C:
400 XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
401 break;
402
403 case MAGIC_R_deref:
404 deref = 1;
405 SvPVX (sv)[0] = MAGIC_R;
406 goto handle_MAGIC_R;
407
408 case MAGIC_CR_deref:
409 deref = 1;
410 case MAGIC_CR:
411 sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
412 if (deref)
413 if (SvPVX (sv)[0] == MAGIC_R_deref)
414 SvPVX (sv)[0] = MAGIC_R;
415
416 goto redo;
417
418 case MAGIC_R:
419 handle_MAGIC_R:
420 if (!storable_mstore)
421 need_storable ();
422
423 PUSHMARK (SP);
424 XPUSHs (sv);
425 PUTBACK;
426
427 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
428 croak ("Storable::mstore didn't return a single scalar");
429
430 SPAGAIN;
431
432 if (deref)
433 {
434 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
435
436 if (SvPVX (sv)[0] == MAGIC_R)
437 SvPVX (sv)[0] = MAGIC_R_deref;
438 }
439 else
440 SETs (sv_2mortal (newSVsv (TOPs)));
441
442 break;
443
444 default:
445 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
446 }
447 }
448 else
449 XPUSHs (sv_2mortal (newSVsv (sv)));
450 }
451