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/cvs/Compress-LZF/LZF.xs
Revision: 1.25
Committed: Wed Jan 9 20:41:18 2008 UTC (16 years, 4 months ago) by root
Branch: MAIN
CVS Tags: rel-3_4, rel-3_11
Changes since 1.24: +15 -3 lines
Log Message:
*** empty log message ***

File Contents

# Content
1 #include "EXTERN.h"
2 #include "perl.h"
3 #include "XSUB.h"
4
5 #define LZF_STANDALONE 1
6 #define LZF_STATE_ARG 1
7
8 #include "lzf_c.c"
9 #include "lzf_d.c"
10
11 /* we re-use the storable header for our purposes */
12 #define MAGIC_LO 0
13 #define MAGIC_U 0 /* uncompressed data follows */
14 #define MAGIC_C 1 /* compressed data follows */
15 #define MAGIC_undef 2 /* the special value undef */
16 #define MAGIC_CR 3 /* storable (reference, freeze), compressed */
17 #define MAGIC_R 4 /* storable (reference, freeze) */
18 #define MAGIC_CR_deref 5 /* storable (NO reference, freeze), compressed */
19 #define MAGIC_R_deref 6 /* storable (NO reference, freeze) */
20 #define MAGIC_HI 7 /* room for one higher storable major */
21 /* for historical reasons, MAGIC_undef + MAGIC_R and MAGIC_undef + MAGIC_R_deref are used, too */
22
23 #define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))
24
25 static SV *serializer_package, *serializer_mstore, *serializer_mretrieve;
26 static CV *storable_mstore, *storable_mretrieve;
27
28 #if Size_t_size > 4
29 # define MAX_LENGTH ((Size_t)0x80000000L)
30 #else
31 # define MAX_LENGTH ((Size_t) 0x8000000L)
32 #endif
33
34 static SV *
35 compress_sv (SV *data, char cprepend, int uprepend)
36 {
37 LZF_STATE *state;
38 STRLEN usize, csize;
39 char *src = (char *)SvPVbyte (data, usize);
40
41 if (usize)
42 {
43 SV *ret = NEWSV (0, usize + 1);
44 unsigned char *dst;
45 int skip = 0;
46
47 SvPOK_only (ret);
48 dst = (unsigned char *)SvPVX (ret);
49
50 if (cprepend)
51 dst[skip++] = cprepend;
52
53 if (usize <= 0x7f)
54 {
55 dst[skip++] = usize;
56 }
57 else if (usize <= 0x7ff)
58 {
59 dst[skip++] = (( usize >> 6) | 0xc0);
60 dst[skip++] = (( usize & 0x3f) | 0x80);
61 }
62 else if (usize <= 0xffff)
63 {
64 dst[skip++] = (( usize >> 12) | 0xe0);
65 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
66 dst[skip++] = (( usize & 0x3f) | 0x80);
67 }
68 else if (usize <= 0x1fffff)
69 {
70 dst[skip++] = (( usize >> 18) | 0xf0);
71 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
72 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
73 dst[skip++] = (( usize & 0x3f) | 0x80);
74 }
75 else if (usize <= 0x3ffffff)
76 {
77 dst[skip++] = (( usize >> 24) | 0xf8);
78 dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
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 <= 0x7fffffff)
84 {
85 dst[skip++] = (( usize >> 30) | 0xfc);
86 dst[skip++] = (((usize >> 24) & 0x3f) | 0x80);
87 dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
88 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
89 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
90 dst[skip++] = (( usize & 0x3f) | 0x80);
91 }
92 else
93 croak ("compress can only compress up to %ld bytes", 0x7fffffffL);
94
95 New (0, state, 1, LZF_STATE);
96 if (!state)
97 croak ("Compress::LZF unable to allocate memory for compression state");
98
99 /* 11 bytes is the smallest compressible string */
100 csize = usize < 11 ? 0 :
101 lzf_compress (src, usize, dst + skip, usize - skip, *state);
102
103 Safefree (state);
104
105 if (csize)
106 {
107 SvCUR_set (ret, csize + skip);
108 }
109 else if (uprepend < 0)
110 {
111 SvREFCNT_dec (ret);
112 ret = SvREFCNT_inc (data);
113 }
114 else
115 {
116 *dst++ = uprepend;
117
118 Move ((void *)src, (void *)dst, usize, unsigned char);
119
120 SvCUR_set (ret, usize + 1);
121 }
122
123 return ret;
124 }
125 else
126 return newSVpv ("", 0);
127 }
128
129 static SV *
130 decompress_sv (SV *data, int skip)
131 {
132 STRLEN usize, csize;
133 unsigned char *src = (unsigned char *)SvPVbyte (data, csize) + skip;
134
135 if (csize)
136 {
137 void *dst;
138 SV *ret;
139
140 csize -= skip;
141
142 if (src[0])
143 {
144 if (!(src[0] & 0x80) && csize >= 1)
145 {
146 csize -= 1;
147 usize = *src++ & 0xff;
148 }
149 else if (!(src[0] & 0x20) && csize >= 2)
150 {
151 csize -= 2;
152 usize = *src++ & 0x1f;
153 usize = (usize << 6) | (*src++ & 0x3f);
154 }
155 else if (!(src[0] & 0x10) && csize >= 3)
156 {
157 csize -= 3;
158 usize = *src++ & 0x0f;
159 usize = (usize << 6) | (*src++ & 0x3f);
160 usize = (usize << 6) | (*src++ & 0x3f);
161 }
162 else if (!(src[0] & 0x08) && csize >= 4)
163 {
164 csize -= 4;
165 usize = *src++ & 0x07;
166 usize = (usize << 6) | (*src++ & 0x3f);
167 usize = (usize << 6) | (*src++ & 0x3f);
168 usize = (usize << 6) | (*src++ & 0x3f);
169 }
170 else if (!(src[0] & 0x04) && csize >= 5)
171 {
172 csize -= 5;
173 usize = *src++ & 0x03;
174 usize = (usize << 6) | (*src++ & 0x3f);
175 usize = (usize << 6) | (*src++ & 0x3f);
176 usize = (usize << 6) | (*src++ & 0x3f);
177 usize = (usize << 6) | (*src++ & 0x3f);
178 }
179 else if (!(src[0] & 0x02) && csize >= 6)
180 {
181 csize -= 6;
182 usize = *src++ & 0x01;
183 usize = (usize << 6) | (*src++ & 0x3f);
184 usize = (usize << 6) | (*src++ & 0x3f);
185 usize = (usize << 6) | (*src++ & 0x3f);
186 usize = (usize << 6) | (*src++ & 0x3f);
187 usize = (usize << 6) | (*src++ & 0x3f);
188 }
189 else
190 croak ("compressed data corrupted (invalid length)");
191
192 if (!usize)
193 croak ("compressed data corrupted (invalid length)");
194
195 ret = NEWSV (0, usize);
196 SvPOK_only (ret);
197 dst = SvPVX (ret);
198
199 if (lzf_decompress (src, csize, dst, usize) != usize)
200 {
201 SvREFCNT_dec (ret);
202 croak ("compressed data corrupted (size mismatch)", csize, skip, usize);
203 }
204 }
205 else
206 {
207 usize = csize - 1;
208 ret = NEWSV (0, usize | 1);
209 SvPOK_only (ret);
210
211 Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
212 }
213
214 SvCUR_set (ret, usize);
215
216 return ret;
217 }
218 else
219 return newSVpvn ("", 0);
220 }
221
222 static void
223 need_storable(void)
224 {
225 load_module (PERL_LOADMOD_NOIMPORT, serializer_package, Nullsv);
226
227 storable_mstore = GvCV (gv_fetchpv (SvPVbyte_nolen (serializer_mstore ), TRUE, SVt_PVCV));
228 storable_mretrieve = GvCV (gv_fetchpv (SvPVbyte_nolen (serializer_mretrieve), TRUE, SVt_PVCV));
229 }
230
231 MODULE = Compress::LZF PACKAGE = Compress::LZF
232
233 BOOT:
234 serializer_package = newSVpv ("Storable", 0);
235 serializer_mstore = newSVpv ("Storable::net_mstore", 0);
236 serializer_mretrieve = newSVpv ("Storable::mretrieve", 0);
237
238 void
239 set_serializer(package, mstore, mretrieve)
240 SV * package
241 SV * mstore
242 SV * mretrieve
243 PROTOTYPE: $$$
244 PPCODE:
245 SvSetSV (serializer_package , package );
246 SvSetSV (serializer_mstore , mstore );
247 SvSetSV (serializer_mretrieve, mretrieve);
248 storable_mstore =
249 storable_mretrieve = 0;
250
251 void
252 compress(data)
253 SV * data
254 PROTOTYPE: $
255 PPCODE:
256 XPUSHs (sv_2mortal (compress_sv (data, 0, MAGIC_U)));
257
258 void
259 decompress(data)
260 SV * data
261 PROTOTYPE: $
262 PPCODE:
263 XPUSHs (sv_2mortal (decompress_sv (data, 0)));
264
265 void
266 sfreeze(sv)
267 SV * sv
268 ALIAS:
269 sfreeze_cr = 1
270 sfreeze_c = 2
271 PROTOTYPE: $
272 PPCODE:
273
274 SvGETMAGIC (sv);
275
276 if (!SvOK (sv))
277 XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
278 else if (SvROK (sv)
279 || SvUTF8 (sv)
280 || (SvTYPE(sv) != SVt_IV
281 && SvTYPE(sv) != SVt_NV
282 && SvTYPE(sv) != SVt_PV
283 && SvTYPE(sv) != SVt_PVIV
284 && SvTYPE(sv) != SVt_PVNV
285 && SvTYPE(sv) != SVt_PVMG)) /* mstore */
286 {
287 int deref = !SvROK (sv);
288
289 if (!storable_mstore)
290 {
291 PUTBACK;
292 need_storable ();
293 SPAGAIN;
294 }
295
296 if (deref)
297 sv = newRV_noinc (sv);
298
299 PUSHMARK (SP);
300 XPUSHs (sv);
301 PUTBACK;
302
303 if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
304 croak ("Storable::mstore didn't return a single scalar");
305
306 SPAGAIN;
307
308 sv = POPs;
309
310 if (SvPVX (sv)[0] == MAGIC_R)
311 {
312 if (deref)
313 SvPVX (sv)[0] = MAGIC_R_deref;
314 }
315 else
316 {
317 char pfx[2];
318
319 pfx[0] = MAGIC_undef;
320 pfx[1] = deref ? MAGIC_R_deref : MAGIC_R;
321
322 sv_insert (sv, 0, 0, pfx, 2);
323 }
324
325 if (ix) /* compress */
326 sv = sv_2mortal (compress_sv (sv, deref ? MAGIC_CR_deref : MAGIC_CR, -1));
327
328 XPUSHs (sv);
329 }
330 else if (SvPOKp (sv) && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
331 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, MAGIC_U))); /* need to prefix only */
332 else if (ix == 2) /* compress always */
333 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, -1)));
334 else if (SvNIOK (sv)) /* don't compress */
335 {
336 STRLEN len;
337 char *s = SvPV (sv, len);
338 XPUSHs (sv_2mortal (newSVpvn (s, len)));
339 }
340 else /* don't compress */
341 XPUSHs (sv_2mortal (newSVsv (sv)));
342
343 void
344 sthaw(sv)
345 SV * sv
346 PROTOTYPE: $
347 PPCODE:
348 {
349 STRLEN svlen;
350 int deref = 0;
351
352 SvGETMAGIC (sv);
353 if (SvPOK (sv) && IN_RANGE (SvPVbyte (sv, svlen)[0], MAGIC_LO, MAGIC_HI))
354 {
355 redo:
356
357 switch (SvPVX (sv)[0])
358 {
359 case MAGIC_undef:
360 if (svlen <= 1)
361 XPUSHs (sv_2mortal (NEWSV (0, 0)));
362 else
363 {
364 if (SvPVX (sv)[1] == MAGIC_R_deref)
365 deref = 1;
366 else if (SvPVX (sv)[1] != MAGIC_R)
367 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
368
369 sv_chop (sv, SvPVX (sv) + 2);
370
371 if (!storable_mstore)
372 {
373 PUTBACK;
374 need_storable ();
375 SPAGAIN;
376 }
377
378 PUSHMARK (SP);
379 XPUSHs (sv);
380 PUTBACK;
381
382 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
383 croak ("Storable::mstore didn't return a single scalar");
384
385 SPAGAIN;
386
387 if (deref)
388 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
389 else
390 SETs (sv_2mortal (newSVsv (TOPs)));
391 }
392 break;
393
394 case MAGIC_U:
395 XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
396 break;
397
398 case MAGIC_C:
399 XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
400 break;
401
402 case MAGIC_R_deref:
403 deref = 1;
404 SvPVX (sv)[0] = MAGIC_R;
405 goto handle_MAGIC_R;
406
407 case MAGIC_CR_deref:
408 deref = 1;
409 case MAGIC_CR:
410 sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
411 if (deref)
412 if (SvPVX (sv)[0] == MAGIC_R_deref)
413 SvPVX (sv)[0] = MAGIC_R;
414
415 goto redo;
416
417 case MAGIC_R:
418 handle_MAGIC_R:
419 if (!storable_mstore)
420 {
421 PUTBACK;
422 need_storable ();
423 SPAGAIN;
424 }
425
426 PUSHMARK (SP);
427 XPUSHs (sv);
428 PUTBACK;
429
430 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
431 croak ("Storable::mstore didn't return a single scalar");
432
433 SPAGAIN;
434
435 if (deref)
436 {
437 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
438
439 if (SvPVX (sv)[0] == MAGIC_R)
440 SvPVX (sv)[0] = MAGIC_R_deref;
441 }
442 else
443 SETs (sv_2mortal (newSVsv (TOPs)));
444
445 break;
446
447 default:
448 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
449 }
450 }
451 else
452 XPUSHs (sv_2mortal (newSVsv (sv)));
453 }
454