ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/Compress-LZF/LZF.xs
Revision: 1.21
Committed: Wed Sep 27 15:52:47 2006 UTC (17 years, 7 months ago) by root
Branch: MAIN
CVS Tags: rel-1_7
Changes since 1.20: +10 -7 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 croak ("compressed data corrupted (size mismatch)", csize, skip, usize);
205 }
206 else
207 {
208 usize = csize - 1;
209 ret = NEWSV (0, usize | 1);
210 SvPOK_only (ret);
211
212 Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
213 }
214
215 SvCUR_set (ret, usize);
216
217 return ret;
218 }
219 else
220 return newSVpvn ("", 0);
221 }
222
223 static void
224 need_storable(void)
225 {
226 #if PATCHLEVEL < 6
227 char req[8192];
228 sprintf (req, "require %s;", SvPV_nolen (serializer_package));
229 perl_eval_pv (req, 1);
230 #else
231 load_module (PERL_LOADMOD_NOIMPORT, serializer_package, Nullsv);
232 #endif
233
234 storable_mstore = GvCV (gv_fetchpv (SvPV_nolen (serializer_mstore ), TRUE, SVt_PVCV));
235 storable_mretrieve = GvCV (gv_fetchpv (SvPV_nolen (serializer_mretrieve), TRUE, SVt_PVCV));
236 }
237
238 MODULE = Compress::LZF PACKAGE = Compress::LZF
239
240 BOOT:
241 serializer_package = newSVpv ("Storable", 0);
242 serializer_mstore = newSVpv ("Storable::net_mstore", 0);
243 serializer_mretrieve = newSVpv ("Storable::mretrieve", 0);
244
245 void
246 set_serializer(package, mstore, mretrieve)
247 SV * package
248 SV * mstore
249 SV * mretrieve
250 PROTOTYPE: $$$
251 PPCODE:
252 SvSetSV (serializer_package , package );
253 SvSetSV (serializer_mstore , mstore );
254 SvSetSV (serializer_mretrieve, mretrieve);
255 storable_mstore =
256 storable_mretrieve = 0;
257
258 void
259 compress(data)
260 SV * data
261 PROTOTYPE: $
262 PPCODE:
263 XPUSHs (sv_2mortal (compress_sv (data, 0, MAGIC_U)));
264
265 void
266 decompress(data)
267 SV * data
268 PROTOTYPE: $
269 PPCODE:
270 XPUSHs (sv_2mortal (decompress_sv (data, 0)));
271
272 void
273 sfreeze(sv)
274 SV * sv
275 ALIAS:
276 sfreeze_cr = 1
277 sfreeze_c = 2
278 PROTOTYPE: $
279 PPCODE:
280
281 SvGETMAGIC (sv);
282
283 if (!SvOK (sv))
284 XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
285 else if (SvROK (sv)
286 || (SvTYPE(sv) != SVt_IV
287 && SvTYPE(sv) != SVt_NV
288 && SvTYPE(sv) != SVt_PV
289 && SvTYPE(sv) != SVt_PVIV
290 && SvTYPE(sv) != SVt_PVNV
291 && SvTYPE(sv) != SVt_PVMG)) /* mstore */
292 {
293 int deref = !SvROK (sv);
294
295 if (!storable_mstore)
296 need_storable ();
297
298 if (deref)
299 sv = newRV_noinc (sv);
300
301 PUSHMARK (SP);
302 XPUSHs (sv);
303 PUTBACK;
304
305 if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
306 croak ("Storable::mstore didn't return a single scalar");
307
308 SPAGAIN;
309
310 sv = POPs;
311
312 if (SvPVX (sv)[0] == MAGIC_R)
313 {
314 if (deref)
315 SvPVX (sv)[0] = MAGIC_R_deref;
316 }
317 else
318 {
319 char pfx[2];
320
321 pfx[0] = MAGIC_undef;
322 pfx[1] = deref ? MAGIC_R_deref : MAGIC_R;
323
324 sv_insert (sv, 0, 0, pfx, 2);
325 }
326
327 if (ix) /* compress */
328 sv = sv_2mortal (compress_sv (sv, deref ? MAGIC_CR_deref : MAGIC_CR, -1));
329
330 XPUSHs (sv);
331 }
332 else if (SvPOKp (sv) && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
333 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, MAGIC_U))); /* need to prefix only */
334 else if (ix == 2) /* compress always */
335 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, -1)));
336 else if (SvNIOK (sv)) /* don't compress */
337 {
338 STRLEN len;
339 char *s = SvPV (sv, len);
340 XPUSHs (sv_2mortal (newSVpvn (s, len)));
341 }
342 else /* don't compress */
343 XPUSHs (sv_2mortal (newSVsv (sv)));
344
345 void
346 sthaw(sv)
347 SV * sv
348 PROTOTYPE: $
349 PPCODE:
350 {
351 STRLEN svlen;
352 int deref = 0;
353
354 SvGETMAGIC (sv);
355 if (SvPOK (sv) && IN_RANGE (SvPV (sv, svlen)[0], MAGIC_LO, MAGIC_HI))
356 {
357 redo:
358
359 switch (SvPVX (sv)[0])
360 {
361 case MAGIC_undef:
362 if (svlen <= 1)
363 XPUSHs (sv_2mortal (NEWSV (0, 0)));
364 else
365 {
366 if (SvPVX (sv)[1] == MAGIC_R_deref)
367 deref = 1;
368 else if (SvPVX (sv)[1] != MAGIC_R)
369 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
370
371 sv_chop (sv, SvPVX (sv) + 2);
372
373 if (!storable_mstore)
374 need_storable ();
375
376 PUSHMARK (SP);
377 XPUSHs (sv);
378 PUTBACK;
379
380 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
381 croak ("Storable::mstore didn't return a single scalar");
382
383 SPAGAIN;
384
385 if (deref)
386 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
387 else
388 SETs (sv_2mortal (newSVsv (TOPs)));
389 }
390 break;
391
392 case MAGIC_U:
393 XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
394 break;
395
396 case MAGIC_C:
397 XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
398 break;
399
400 case MAGIC_R_deref:
401 deref = 1;
402 SvPVX (sv)[0] = MAGIC_R;
403 goto handle_MAGIC_R;
404
405 case MAGIC_CR_deref:
406 deref = 1;
407 case MAGIC_CR:
408 sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
409 if (deref)
410 if (SvPVX (sv)[0] == MAGIC_R_deref)
411 SvPVX (sv)[0] = MAGIC_R;
412
413 goto redo;
414
415 case MAGIC_R:
416 handle_MAGIC_R:
417 if (!storable_mstore)
418 need_storable ();
419
420 PUSHMARK (SP);
421 XPUSHs (sv);
422 PUTBACK;
423
424 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
425 croak ("Storable::mstore didn't return a single scalar");
426
427 SPAGAIN;
428
429 if (deref)
430 {
431 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
432
433 if (SvPVX (sv)[0] == MAGIC_R)
434 SvPVX (sv)[0] = MAGIC_R_deref;
435 }
436 else
437 SETs (sv_2mortal (newSVsv (TOPs)));
438
439 break;
440
441 default:
442 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
443 }
444 }
445 else
446 XPUSHs (sv_2mortal (newSVsv (sv)));
447 }
448