Compress-LZF/LZF.xs

#include "EXTERN.h"
#include "perl.h"
#include "XSUB.h"

/* try to be compatible with older perls */
/* SvPV_nolen() macro first defined in 5.005_55 */
/* this is slow, not threadsafe, but works */
#include "patchlevel.h"
#if (PATCHLEVEL == 4) || ((PATCHLEVEL == 5) && (SUBVERSION < 55))
static STRLEN nolen_na;
# define SvPV_nolen(sv) SvPV ((sv), nolen_na)
#endif
#if PATCHLEVEL < 6
# define call_sv perl_call_sv
#endif

#include "lzf_c.c"
#include "lzf_d.c"

/* we re-use the storable header for our purposes */
#define MAGIC_LO        0
#define MAGIC_U         0 /* uncompressed data follows */
#define MAGIC_C         1 /* compressed data follows */
#define MAGIC_R         4 /* storable (reference, freeze) */
#define MAGIC_CR        3 /* storable (reference, freeze), compressed */
#define MAGIC_HI        7 /* room for one higher storable major */

#define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))

static CV *storable_mstore, *storable_mretrieve;

static SV *
compress_sv (SV *data, char cprepend, char uprepend)
{
  STRLEN usize, csize;
  char *src = (char *)SvPV (data, usize);

  if (usize)
    {
      SV *ret = NEWSV (0, usize + 1);
      unsigned char *dst;
      int skip = 0;

      SvPOK_only (ret);
      dst = (unsigned char *)SvPVX (ret);

      if (cprepend)
        dst[skip++] = cprepend;

      if (usize < 0x80)
        {
          dst[skip++] = usize;
        }
      else if (usize < 0x800) 
        {
          dst[skip++] = (( usize >>  6)         | 0xc0);
          dst[skip++] = (( usize        & 0x3f) | 0x80);
        }
      else if (usize < 0x10000) 
        {
          dst[skip++] = (( usize >> 12)         | 0xe0);
          dst[skip++] = (((usize >>  6) & 0x3f) | 0x80);
          dst[skip++] = (( usize        & 0x3f) | 0x80);
        }
      else if (usize < 0x200000) 
        {
          dst[skip++] = (( usize >> 18)         | 0xf0);
          dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
          dst[skip++] = (((usize >>  6) & 0x3f) | 0x80);
          dst[skip++] = (( usize        & 0x3f) | 0x80);
        }
      else if (usize < 0x4000000) 
        {
          dst[skip++] = (( usize >> 24)         | 0xf8);
          dst[skip++] = (((usize >> 18) & 0x3f) | 0x80);
          dst[skip++] = (((usize >> 12) & 0x3f) | 0x80);
          dst[skip++] = (((usize >>  6) & 0x3f) | 0x80);
          dst[skip++] = (( usize        & 0x3f) | 0x80);
        }
      else
        croak ("compress can only compress up to %ld bytes", 0x4000000-1);

      /* 11 bytes is the smallest compressible string */
      csize = usize < 11 ? 0 :
              lzf_compress (src, usize,
                                  dst + skip,
                                  usize - skip);

      if (csize)
        {
          SvCUR_set (ret, csize + skip);
        }
      else if (!uprepend)
        {
          SvREFCNT_dec (ret);
          ret = SvREFCNT_inc (data);
        }
      else
        {
          *dst++ = 0;

          Move ((void *)src, (void *)dst, usize, unsigned char);

          SvCUR_set (ret, usize + 1);
        }

      return ret;
    }
  else
    return newSVpv ("", 0);
}

static SV *
decompress_sv (SV *data, int skip)
{
  STRLEN usize, csize;
  unsigned char *src = (unsigned char *)SvPV (data, csize) + skip;

  if (csize)
    {
      void *dst;
      SV *ret;

      csize -= skip;

      if (src[0])
        {
          if (!(src[0] & 0x80))
            {
              csize -= 1;
              usize =                 *src++ & 0xff;
            }
          else if (!(src[0] & 0x20))
            {
              csize -= 2;
              usize =                 *src++ & 0x1f;
              usize = (usize << 6) | (*src++ & 0x3f);
            }
          else if (!(src[0] & 0x10))
            {
              csize -= 3;
              usize =                 *src++ & 0x0f;
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
            }
          else if (!(src[0] & 0x08))
            {
              csize -= 4;
              usize =                 *src++ & 0x07;
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
            }
          else if (!(src[0] & 0x04))
            {
              csize -= 5;
              usize =                 *src++ & 0x03;
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
              usize = (usize << 6) | (*src++ & 0x3f);
            }
          else
            croak ("compressed data corrupted");
                    
          ret = NEWSV (0, usize);
          SvPOK_only (ret);
          dst = SvPVX (ret);

          if (lzf_decompress (src, csize, dst, usize) != usize)
            croak ("compressed data corrupted", csize, skip, usize);
        }
      else
        {
          usize = csize - 1;
          ret = NEWSV (0, usize);
          SvPOK_only (ret);

          Move ((void *)(src + 1), (void *)SvPVX (ret), usize, unsigned char);
      }

      SvCUR_set (ret, usize);

      return ret;
    }
  else
    return newSVpvn ("", 0);
}

static void
need_storable(void)
{
#if PATCHLEVEL < 6
  perl_eval_pv ("require Storable;", 1);
#else
  load_module (PERL_LOADMOD_NOIMPORT, newSVpv ("Storable", 0), Nullsv);
#endif

  storable_mstore    = GvCV (gv_fetchpv ("Storable::mstore"   , TRUE, SVt_PVCV));
  storable_mretrieve = GvCV (gv_fetchpv ("Storable::mretrieve", TRUE, SVt_PVCV));
}

MODULE = Compress::LZF   PACKAGE = Compress::LZF

void
compress(data)
        SV *    data
        PROTOTYPE: $
        PPCODE:
        XPUSHs (sv_2mortal (compress_sv (data, 0, 1)));

void
decompress(data)
        SV *    data
        PROTOTYPE: $
        PPCODE:
        XPUSHs (sv_2mortal (decompress_sv (data, 0)));

void
sfreeze(sv)
        SV *    sv
        ALIAS:
        sfreeze_cr = 1
        sfreeze_c  = 2
        PROTOTYPE: $
        PPCODE:

        if (SvROK (sv)) /* mstore */
          {
            if (!storable_mstore)
              need_storable ();

            PUSHMARK (SP);
            XPUSHs (sv);
            PUTBACK;

            if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
              croak ("Storable::mstore didn't return a single scalar");

            SPAGAIN;

            sv = POPs;

            if (SvPVX (sv)[0] != MAGIC_R)
              croak ("Storable format changed, need newer version of Compress::LZF");

            if (ix) /* compress */
              XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_CR, 0)));
            else
              XPUSHs (sv);
          }
        else if (IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
          XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 1))); /* need to prefix only */
        else if (ix == 2) /* compress always */
          XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 0)));
        else /* don't compress */
          XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));

void
sthaw(sv)
        SV *    sv
        PROTOTYPE: $
        PPCODE:
        char hdr = SvPVX (sv)[0];

        if (IN_RANGE (hdr, MAGIC_LO, MAGIC_HI))
          {
            switch (SvPVX (sv)[0])
              {
                case MAGIC_U:
                  XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
                  break;

                case MAGIC_C:
                  XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
                  break;

                case MAGIC_CR:
                  sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
                case MAGIC_R:
                  if (!storable_mstore)
                    need_storable ();

                  PUSHMARK (SP);
                  XPUSHs (sv);
                  PUTBACK;

                  if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
                    croak ("Storable::mstore didn't return a single scalar");

                  SPAGAIN;

                  /*XPUSHs (POPs);*/

                  break; 

                default:
                  croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
              }
          }
        else
          XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));
Revision:	1.2
Committed:	Thu Sep 27 19:24:55 2001 UTC (22 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.1:	+7 -0 lines
Log Message:	* empty log message *
#	User	Rev	Content
1	root	1.1	#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	root	1.2	#if PATCHLEVEL < 6
14			# define call_sv perl_call_sv
15			#endif
16	root	1.1
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_R 4 /* storable (reference, freeze) */
25			#define MAGIC_CR 3 /* storable (reference, freeze), compressed */
26			#define MAGIC_HI 7 /* room for one higher storable major */
27
28			#define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))
29
30			static CV storable_mstore, storable_mretrieve;
31
32			static SV *
33			compress_sv (SV *data, char cprepend, char uprepend)
34			{
35			STRLEN usize, csize;
36			char src = (char )SvPV (data, usize);
37
38			if (usize)
39			{
40			SV *ret = NEWSV (0, usize + 1);
41			unsigned char *dst;
42			int skip = 0;
43
44			SvPOK_only (ret);
45			dst = (unsigned char *)SvPVX (ret);
46
47			if (cprepend)
48			dst[skip++] = cprepend;
49
50			if (usize < 0x80)
51			{
52			dst[skip++] = usize;
53			}
54			else if (usize < 0x800)
55			{
56			dst[skip++] = (( usize >> 6) \| 0xc0);
57			dst[skip++] = (( usize & 0x3f) \| 0x80);
58			}
59			else if (usize < 0x10000)
60			{
61			dst[skip++] = (( usize >> 12) \| 0xe0);
62			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
63			dst[skip++] = (( usize & 0x3f) \| 0x80);
64			}
65			else if (usize < 0x200000)
66			{
67			dst[skip++] = (( usize >> 18) \| 0xf0);
68			dst[skip++] = (((usize >> 12) & 0x3f) \| 0x80);
69			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
70			dst[skip++] = (( usize & 0x3f) \| 0x80);
71			}
72			else if (usize < 0x4000000)
73			{
74			dst[skip++] = (( usize >> 24) \| 0xf8);
75			dst[skip++] = (((usize >> 18) & 0x3f) \| 0x80);
76			dst[skip++] = (((usize >> 12) & 0x3f) \| 0x80);
77			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
78			dst[skip++] = (( usize & 0x3f) \| 0x80);
79			}
80			else
81			croak ("compress can only compress up to %ld bytes", 0x4000000-1);
82
83			/* 11 bytes is the smallest compressible string */
84			csize = usize < 11 ? 0 :
85			lzf_compress (src, usize,
86			dst + skip,
87			usize - skip);
88
89			if (csize)
90			{
91			SvCUR_set (ret, csize + skip);
92			}
93			else if (!uprepend)
94			{
95			SvREFCNT_dec (ret);
96			ret = SvREFCNT_inc (data);
97			}
98			else
99			{
100			*dst++ = 0;
101
102			Move ((void )src, (void )dst, usize, unsigned char);
103
104			SvCUR_set (ret, usize + 1);
105			}
106
107			return ret;
108			}
109			else
110			return newSVpv ("", 0);
111			}
112
113			static SV *
114			decompress_sv (SV *data, int skip)
115			{
116			STRLEN usize, csize;
117			unsigned char src = (unsigned char )SvPV (data, csize) + skip;
118
119			if (csize)
120			{
121			void *dst;
122			SV *ret;
123
124			csize -= skip;
125
126			if (src[0])
127			{
128			if (!(src[0] & 0x80))
129			{
130			csize -= 1;
131			usize = *src++ & 0xff;
132			}
133			else if (!(src[0] & 0x20))
134			{
135			csize -= 2;
136			usize = *src++ & 0x1f;
137			usize = (usize << 6) \| (*src++ & 0x3f);
138			}
139			else if (!(src[0] & 0x10))
140			{
141			csize -= 3;
142			usize = *src++ & 0x0f;
143			usize = (usize << 6) \| (*src++ & 0x3f);
144			usize = (usize << 6) \| (*src++ & 0x3f);
145			}
146			else if (!(src[0] & 0x08))
147			{
148			csize -= 4;
149			usize = *src++ & 0x07;
150			usize = (usize << 6) \| (*src++ & 0x3f);
151			usize = (usize << 6) \| (*src++ & 0x3f);
152			usize = (usize << 6) \| (*src++ & 0x3f);
153			}
154			else if (!(src[0] & 0x04))
155			{
156			csize -= 5;
157			usize = *src++ & 0x03;
158			usize = (usize << 6) \| (*src++ & 0x3f);
159			usize = (usize << 6) \| (*src++ & 0x3f);
160			usize = (usize << 6) \| (*src++ & 0x3f);
161			usize = (usize << 6) \| (*src++ & 0x3f);
162			}
163			else
164			croak ("compressed data corrupted");
165
166			ret = NEWSV (0, usize);
167			SvPOK_only (ret);
168			dst = SvPVX (ret);
169
170			if (lzf_decompress (src, csize, dst, usize) != usize)
171			croak ("compressed data corrupted", csize, skip, usize);
172			}
173			else
174			{
175			usize = csize - 1;
176			ret = NEWSV (0, usize);
177			SvPOK_only (ret);
178
179			Move ((void )(src + 1), (void )SvPVX (ret), usize, unsigned char);
180			}
181
182			SvCUR_set (ret, usize);
183
184			return ret;
185			}
186			else
187			return newSVpvn ("", 0);
188			}
189
190			static void
191			need_storable(void)
192			{
193	root	1.2	#if PATCHLEVEL < 6
194			perl_eval_pv ("require Storable;", 1);
195			#else
196	root	1.1	load_module (PERL_LOADMOD_NOIMPORT, newSVpv ("Storable", 0), Nullsv);
197	root	1.2	#endif
198	root	1.1
199			storable_mstore = GvCV (gv_fetchpv ("Storable::mstore" , TRUE, SVt_PVCV));
200			storable_mretrieve = GvCV (gv_fetchpv ("Storable::mretrieve", TRUE, SVt_PVCV));
201			}
202
203			MODULE = Compress::LZF PACKAGE = Compress::LZF
204
205			void
206			compress(data)
207			SV * data
208			PROTOTYPE: $
209			PPCODE:
210			XPUSHs (sv_2mortal (compress_sv (data, 0, 1)));
211
212			void
213			decompress(data)
214			SV * data
215			PROTOTYPE: $
216			PPCODE:
217			XPUSHs (sv_2mortal (decompress_sv (data, 0)));
218
219			void
220			sfreeze(sv)
221			SV * sv
222			ALIAS:
223			sfreeze_cr = 1
224			sfreeze_c = 2
225			PROTOTYPE: $
226			PPCODE:
227
228			if (SvROK (sv)) /* mstore */
229			{
230			if (!storable_mstore)
231			need_storable ();
232
233			PUSHMARK (SP);
234			XPUSHs (sv);
235			PUTBACK;
236
237			if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
238			croak ("Storable::mstore didn't return a single scalar");
239
240			SPAGAIN;
241
242			sv = POPs;
243
244			if (SvPVX (sv)[0] != MAGIC_R)
245			croak ("Storable format changed, need newer version of Compress::LZF");
246
247			if (ix) /* compress */
248			XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_CR, 0)));
249			else
250			XPUSHs (sv);
251			}
252			else if (IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
253			XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 1))); /* need to prefix only */
254			else if (ix == 2) /* compress always */
255			XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 0)));
256			else /* don't compress */
257			XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));
258
259			void
260			sthaw(sv)
261			SV * sv
262			PROTOTYPE: $
263			PPCODE:
264			char hdr = SvPVX (sv)[0];
265
266			if (IN_RANGE (hdr, MAGIC_LO, MAGIC_HI))
267			{
268			switch (SvPVX (sv)[0])
269			{
270			case MAGIC_U:
271			XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
272			break;
273
274			case MAGIC_C:
275			XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
276			break;
277
278			case MAGIC_CR:
279			sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
280			case MAGIC_R:
281			if (!storable_mstore)
282			need_storable ();
283
284			PUSHMARK (SP);
285			XPUSHs (sv);
286			PUTBACK;
287
288			if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
289			croak ("Storable::mstore didn't return a single scalar");
290
291			SPAGAIN;
292
293			/XPUSHs (POPs);/
294
295			break;
296
297			default:
298			croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
299			}
300			}
301			else
302			XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));