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/cvs/Compress-LZF/LZF.xs
Revision: 1.18
Committed: Tue Aug 3 15:04:05 2004 UTC (19 years, 9 months ago) by pcg
Branch: MAIN
Changes since 1.17: +3 -0 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 #define HLOG 15
18 #define ULTRA_FAST 0
19
20 #include "lzf_c.c"
21 #include "lzf_d.c"
22
23 /* we re-use the storable header for our purposes */
24 #define MAGIC_LO 0
25 #define MAGIC_U 0 /* uncompressed data follows */
26 #define MAGIC_C 1 /* compressed data follows */
27 #define MAGIC_undef 2 /* the special value undef */
28 #define MAGIC_CR 3 /* storable (reference, freeze), compressed */
29 #define MAGIC_R 4 /* storable (reference, freeze) */
30 #define MAGIC_CR_deref 5 /* storable (NO reference, freeze), compressed */
31 #define MAGIC_R_deref 6 /* storable (NO reference, freeze) */
32 #define MAGIC_HI 7 /* room for one higher storable major */
33
34 #define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))
35
36 static SV *serializer_package, *serializer_mstore, *serializer_mretrieve;
37 static CV *storable_mstore, *storable_mretrieve;
38
39 static SV *
40 compress_sv (SV *data, char cprepend, int uprepend)
41 {
42 STRLEN usize, csize;
43 char *src = (char *)SvPV (data, usize);
44
45 if (usize)
46 {
47 SV *ret = NEWSV (0, usize + 1);
48 unsigned char *dst;
49 int skip = 0;
50
51 SvPOK_only (ret);
52 dst = (unsigned char *)SvPVX (ret);
53
54 if (cprepend)
55 dst[skip++] = cprepend;
56
57 if (usize < 0x80)
58 {
59 dst[skip++] = usize;
60 }
61 else if (usize < 0x800)
62 {
63 dst[skip++] = (( usize >> 6) | 0xc0);
64 dst[skip++] = (( usize & 0x3f) | 0x80);
65 }
66 else if (usize < 0x10000)
67 {
68 dst[skip++] = (( usize >> 12) | 0xe0);
69 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
70 dst[skip++] = (( usize & 0x3f) | 0x80);
71 }
72 else if (usize < 0x200000)
73 {
74 dst[skip++] = (( usize >> 18) | 0xf0);
75 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
76 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
77 dst[skip++] = (( usize & 0x3f) | 0x80);
78 }
79 else if (usize < 0x4000000)
80 {
81 dst[skip++] = (( usize >> 24) | 0xf8);
82 dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
83 dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
84 dst[skip++] = (((usize >> 6) & 0x3f) | 0x80);
85 dst[skip++] = (( usize & 0x3f) | 0x80);
86 }
87 else
88 croak ("compress can only compress up to %ld bytes", 0x4000000-1);
89
90 /* 11 bytes is the smallest compressible string */
91 csize = usize < 11 ? 0 :
92 lzf_compress (src, usize,
93 dst + skip,
94 usize - skip);
95
96 if (csize)
97 {
98 SvCUR_set (ret, csize + skip);
99 }
100 else if (uprepend < 0)
101 {
102 SvREFCNT_dec (ret);
103 ret = SvREFCNT_inc (data);
104 }
105 else
106 {
107 *dst++ = uprepend;
108
109 Move ((void *)src, (void *)dst, usize, unsigned char);
110
111 SvCUR_set (ret, usize + 1);
112 }
113
114 return ret;
115 }
116 else
117 return newSVpv ("", 0);
118 }
119
120 static SV *
121 decompress_sv (SV *data, int skip)
122 {
123 STRLEN usize, csize;
124 unsigned char *src = (unsigned char *)SvPV (data, csize) + skip;
125
126 if (csize)
127 {
128 void *dst;
129 SV *ret;
130
131 csize -= skip;
132
133 if (src[0])
134 {
135 if (!(src[0] & 0x80))
136 {
137 csize -= 1;
138 usize = *src++ & 0xff;
139 }
140 else if (!(src[0] & 0x20))
141 {
142 csize -= 2;
143 usize = *src++ & 0x1f;
144 usize = (usize << 6) | (*src++ & 0x3f);
145 }
146 else if (!(src[0] & 0x10))
147 {
148 csize -= 3;
149 usize = *src++ & 0x0f;
150 usize = (usize << 6) | (*src++ & 0x3f);
151 usize = (usize << 6) | (*src++ & 0x3f);
152 }
153 else if (!(src[0] & 0x08))
154 {
155 csize -= 4;
156 usize = *src++ & 0x07;
157 usize = (usize << 6) | (*src++ & 0x3f);
158 usize = (usize << 6) | (*src++ & 0x3f);
159 usize = (usize << 6) | (*src++ & 0x3f);
160 }
161 else if (!(src[0] & 0x04))
162 {
163 csize -= 5;
164 usize = *src++ & 0x03;
165 usize = (usize << 6) | (*src++ & 0x3f);
166 usize = (usize << 6) | (*src++ & 0x3f);
167 usize = (usize << 6) | (*src++ & 0x3f);
168 usize = (usize << 6) | (*src++ & 0x3f);
169 }
170 else
171 croak ("compressed data corrupted (invalid length)");
172
173 ret = NEWSV (0, usize);
174 SvPOK_only (ret);
175 dst = SvPVX (ret);
176
177 if (lzf_decompress (src, csize, dst, usize) != usize)
178 croak ("compressed data corrupted (size mismatch)", csize, skip, usize);
179 }
180 else
181 {
182 usize = csize - 1;
183 ret = NEWSV (0, usize);
184 SvPOK_only (ret);
185
186 Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
187 }
188
189 SvCUR_set (ret, usize);
190
191 return ret;
192 }
193 else
194 return newSVpvn ("", 0);
195 }
196
197 static void
198 need_storable(void)
199 {
200 #if PATCHLEVEL < 6
201 char req[8192];
202 sprintf (req, "require %s;", SvPV_nolen (serializer_package));
203 perl_eval_pv (req, 1);
204 #else
205 load_module (PERL_LOADMOD_NOIMPORT, serializer_package, Nullsv);
206 #endif
207
208 storable_mstore = GvCV (gv_fetchpv (SvPV_nolen (serializer_mstore ), TRUE, SVt_PVCV));
209 storable_mretrieve = GvCV (gv_fetchpv (SvPV_nolen (serializer_mretrieve), TRUE, SVt_PVCV));
210 }
211
212 MODULE = Compress::LZF PACKAGE = Compress::LZF
213
214 BOOT:
215 serializer_package = newSVpv ("Storable", 0);
216 serializer_mstore = newSVpv ("Storable::mstore", 0);
217 serializer_mretrieve = newSVpv ("Storable::mretrieve", 0);
218
219 void
220 set_serializer(package, mstore, mretrieve)
221 SV * package
222 SV * mstore
223 SV * mretrieve
224 PROTOTYPE: $$$
225 PPCODE:
226 SvSetSV (serializer_package , package );
227 SvSetSV (serializer_mstore , mstore );
228 SvSetSV (serializer_mretrieve, mretrieve);
229 storable_mstore =
230 storable_mretrieve = 0;
231
232 void
233 compress(data)
234 SV * data
235 PROTOTYPE: $
236 PPCODE:
237 XPUSHs (sv_2mortal (compress_sv (data, 0, MAGIC_U)));
238
239 void
240 decompress(data)
241 SV * data
242 PROTOTYPE: $
243 PPCODE:
244 XPUSHs (sv_2mortal (decompress_sv (data, 0)));
245
246 void
247 sfreeze(sv)
248 SV * sv
249 ALIAS:
250 sfreeze_cr = 1
251 sfreeze_c = 2
252 PROTOTYPE: $
253 PPCODE:
254
255 SvGETMAGIC (sv);
256
257 if (!SvOK (sv))
258 XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
259 else if (SvROK (sv)
260 || (SvTYPE(sv) != SVt_IV
261 && SvTYPE(sv) != SVt_NV
262 && SvTYPE(sv) != SVt_PV
263 && SvTYPE(sv) != SVt_PVIV
264 && SvTYPE(sv) != SVt_PVNV
265 && SvTYPE(sv) != SVt_PVMG)) /* mstore */
266 {
267 int deref = !SvROK (sv);
268
269 if (!storable_mstore)
270 need_storable ();
271
272 if (deref)
273 sv = newRV_noinc (sv);
274
275 PUSHMARK (SP);
276 XPUSHs (sv);
277 PUTBACK;
278
279 if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
280 croak ("Storable::mstore didn't return a single scalar");
281
282 SPAGAIN;
283
284 sv = POPs;
285
286 if (SvPVX (sv)[0] != MAGIC_R)
287 croak ("Storable format changed, need newer version of Compress::LZF");
288
289 if (deref)
290 SvPVX (sv)[0] = MAGIC_R_deref;
291
292 if (ix) /* compress */
293 sv = sv_2mortal (compress_sv (sv, deref ? MAGIC_CR_deref : MAGIC_CR, -1));
294
295 XPUSHs (sv);
296 }
297 else if (SvPOKp (sv) && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
298 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, MAGIC_U))); /* need to prefix only */
299 else if (ix == 2) /* compress always */
300 XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, -1)));
301 else if (SvNIOK (sv)) /* don't compress */
302 {
303 STRLEN len;
304 char *s = SvPV (sv, len);
305 XPUSHs (sv_2mortal (newSVpvn (s, len)));
306 }
307 else /* don't compress */
308 XPUSHs (sv_2mortal (newSVsv (sv)));
309
310 void
311 sthaw(sv)
312 SV * sv
313 PROTOTYPE: $
314 PPCODE:
315
316 int deref = 0;
317
318 SvGETMAGIC (sv);
319 if (SvPOK (sv) && IN_RANGE (SvPV_nolen (sv)[0], MAGIC_LO, MAGIC_HI))
320 {
321 switch (SvPVX (sv)[0])
322 {
323 case MAGIC_undef:
324 XPUSHs (sv_2mortal (NEWSV (0, 0)));
325 break;
326
327 case MAGIC_U:
328 XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
329 break;
330
331 case MAGIC_C:
332 XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
333 break;
334
335 case MAGIC_R_deref:
336 deref = 1;
337 SvPVX (sv)[0] = MAGIC_R;
338 goto handle_MAGIC_R;
339
340 case MAGIC_CR_deref:
341 deref = 1;
342 case MAGIC_CR:
343 sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
344 if (deref)
345 if (SvPVX (sv)[0] == MAGIC_R_deref)
346 SvPVX (sv)[0] = MAGIC_R;
347 else
348 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
349
350 case MAGIC_R:
351 handle_MAGIC_R:
352 if (!storable_mstore)
353 need_storable ();
354
355 PUSHMARK (SP);
356 XPUSHs (sv);
357 PUTBACK;
358
359 if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
360 croak ("Storable::mstore didn't return a single scalar");
361
362 SPAGAIN;
363
364 if (deref)
365 {
366 SETs (sv_2mortal (SvREFCNT_inc (SvRV (TOPs))));
367
368 if (SvPVX (sv)[0] == MAGIC_R)
369 SvPVX (sv)[0] = MAGIC_R_deref;
370 }
371 else
372 SETs (sv_2mortal (newSVsv (TOPs)));
373
374 break;
375
376 default:
377 croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
378 }
379 }
380 else
381 XPUSHs (sv_2mortal (newSVsv (sv)));
382