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_undef     2 /* the special value undef */
#define MAGIC_CR        3 /* storable (reference, freeze), compressed */
#define MAGIC_R         4 /* storable (reference, freeze) */
#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 (!SvOK (sv))
          XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
        else if (SvTYPE(sv) != SVt_IV
            && SvTYPE(sv) != SVt_NV
            && SvTYPE(sv) != SVt_PV) /* 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 (sv && 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:

        if (IN_RANGE (SvPV_nolen (sv)[0], MAGIC_LO, MAGIC_HI))
          {
            switch (SvPVX (sv)[0])
              {
                case MAGIC_undef:
                  XPUSHs (sv_2mortal (NEWSV (0, 0)));
                  break;

                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); /* this is a nop, hope the compiler also knows this */

                  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:	1.4
Committed:	Thu Sep 27 20:05:38 2001 UTC (22 years, 7 months ago) by root
Branch:	MAIN
Changes since 1.3:	+12 -6 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	root	1.4	#define MAGIC_undef 2 /* the special value undef */
25			#define MAGIC_CR 3 /* storable (reference, freeze), compressed */
26	root	1.1	#define MAGIC_R 4 /* storable (reference, freeze) */
27			#define MAGIC_HI 7 /* room for one higher storable major */
28
29			#define IN_RANGE(v,l,h) ((unsigned int)((unsigned)(v) - (unsigned)(l)) <= (unsigned)(h) - (unsigned)(l))
30
31			static CV storable_mstore, storable_mretrieve;
32
33			static SV *
34			compress_sv (SV *data, char cprepend, char uprepend)
35			{
36			STRLEN usize, csize;
37			char src = (char )SvPV (data, usize);
38
39			if (usize)
40			{
41			SV *ret = NEWSV (0, usize + 1);
42			unsigned char *dst;
43			int skip = 0;
44
45			SvPOK_only (ret);
46			dst = (unsigned char *)SvPVX (ret);
47
48			if (cprepend)
49			dst[skip++] = cprepend;
50
51			if (usize < 0x80)
52			{
53			dst[skip++] = usize;
54			}
55			else if (usize < 0x800)
56			{
57			dst[skip++] = (( usize >> 6) \| 0xc0);
58			dst[skip++] = (( usize & 0x3f) \| 0x80);
59			}
60			else if (usize < 0x10000)
61			{
62			dst[skip++] = (( usize >> 12) \| 0xe0);
63			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
64			dst[skip++] = (( usize & 0x3f) \| 0x80);
65			}
66			else if (usize < 0x200000)
67			{
68			dst[skip++] = (( usize >> 18) \| 0xf0);
69			dst[skip++] = (((usize >> 12) & 0x3f) \| 0x80);
70			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
71			dst[skip++] = (( usize & 0x3f) \| 0x80);
72			}
73			else if (usize < 0x4000000)
74			{
75			dst[skip++] = (( usize >> 24) \| 0xf8);
76			dst[skip++] = (((usize >> 18) & 0x3f) \| 0x80);
77			dst[skip++] = (((usize >> 12) & 0x3f) \| 0x80);
78			dst[skip++] = (((usize >> 6) & 0x3f) \| 0x80);
79			dst[skip++] = (( usize & 0x3f) \| 0x80);
80			}
81			else
82			croak ("compress can only compress up to %ld bytes", 0x4000000-1);
83
84			/* 11 bytes is the smallest compressible string */
85			csize = usize < 11 ? 0 :
86			lzf_compress (src, usize,
87			dst + skip,
88			usize - skip);
89
90			if (csize)
91			{
92			SvCUR_set (ret, csize + skip);
93			}
94			else if (!uprepend)
95			{
96			SvREFCNT_dec (ret);
97			ret = SvREFCNT_inc (data);
98			}
99			else
100			{
101			*dst++ = 0;
102
103			Move ((void )src, (void )dst, usize, unsigned char);
104
105			SvCUR_set (ret, usize + 1);
106			}
107
108			return ret;
109			}
110			else
111			return newSVpv ("", 0);
112			}
113
114			static SV *
115			decompress_sv (SV *data, int skip)
116			{
117			STRLEN usize, csize;
118			unsigned char src = (unsigned char )SvPV (data, csize) + skip;
119
120			if (csize)
121			{
122			void *dst;
123			SV *ret;
124
125			csize -= skip;
126
127			if (src[0])
128			{
129			if (!(src[0] & 0x80))
130			{
131			csize -= 1;
132			usize = *src++ & 0xff;
133			}
134			else if (!(src[0] & 0x20))
135			{
136			csize -= 2;
137			usize = *src++ & 0x1f;
138			usize = (usize << 6) \| (*src++ & 0x3f);
139			}
140			else if (!(src[0] & 0x10))
141			{
142			csize -= 3;
143			usize = *src++ & 0x0f;
144			usize = (usize << 6) \| (*src++ & 0x3f);
145			usize = (usize << 6) \| (*src++ & 0x3f);
146			}
147			else if (!(src[0] & 0x08))
148			{
149			csize -= 4;
150			usize = *src++ & 0x07;
151			usize = (usize << 6) \| (*src++ & 0x3f);
152			usize = (usize << 6) \| (*src++ & 0x3f);
153			usize = (usize << 6) \| (*src++ & 0x3f);
154			}
155			else if (!(src[0] & 0x04))
156			{
157			csize -= 5;
158			usize = *src++ & 0x03;
159			usize = (usize << 6) \| (*src++ & 0x3f);
160			usize = (usize << 6) \| (*src++ & 0x3f);
161			usize = (usize << 6) \| (*src++ & 0x3f);
162			usize = (usize << 6) \| (*src++ & 0x3f);
163			}
164			else
165			croak ("compressed data corrupted");
166
167			ret = NEWSV (0, usize);
168			SvPOK_only (ret);
169			dst = SvPVX (ret);
170
171			if (lzf_decompress (src, csize, dst, usize) != usize)
172			croak ("compressed data corrupted", csize, skip, usize);
173			}
174			else
175			{
176			usize = csize - 1;
177			ret = NEWSV (0, usize);
178			SvPOK_only (ret);
179
180			Move ((void )(src + 1), (void )SvPVX (ret), usize, unsigned char);
181			}
182
183			SvCUR_set (ret, usize);
184
185			return ret;
186			}
187			else
188			return newSVpvn ("", 0);
189			}
190
191			static void
192			need_storable(void)
193			{
194	root	1.2	#if PATCHLEVEL < 6
195			perl_eval_pv ("require Storable;", 1);
196			#else
197	root	1.1	load_module (PERL_LOADMOD_NOIMPORT, newSVpv ("Storable", 0), Nullsv);
198	root	1.2	#endif
199	root	1.1
200			storable_mstore = GvCV (gv_fetchpv ("Storable::mstore" , TRUE, SVt_PVCV));
201			storable_mretrieve = GvCV (gv_fetchpv ("Storable::mretrieve", TRUE, SVt_PVCV));
202			}
203
204			MODULE = Compress::LZF PACKAGE = Compress::LZF
205
206			void
207			compress(data)
208			SV * data
209			PROTOTYPE: $
210			PPCODE:
211			XPUSHs (sv_2mortal (compress_sv (data, 0, 1)));
212
213			void
214			decompress(data)
215			SV * data
216			PROTOTYPE: $
217			PPCODE:
218			XPUSHs (sv_2mortal (decompress_sv (data, 0)));
219
220			void
221			sfreeze(sv)
222			SV * sv
223			ALIAS:
224			sfreeze_cr = 1
225			sfreeze_c = 2
226			PROTOTYPE: $
227			PPCODE:
228
229	root	1.4	if (!SvOK (sv))
230			XPUSHs (sv_2mortal (newSVpvn ("\02", 1))); /* 02 == MAGIC_undef */
231			else if (SvTYPE(sv) != SVt_IV
232	root	1.3	&& SvTYPE(sv) != SVt_NV
233			&& SvTYPE(sv) != SVt_PV) /* mstore */
234	root	1.1	{
235			if (!storable_mstore)
236			need_storable ();
237
238			PUSHMARK (SP);
239			XPUSHs (sv);
240			PUTBACK;
241
242			if (1 != call_sv ((SV *)storable_mstore, G_SCALAR))
243			croak ("Storable::mstore didn't return a single scalar");
244
245			SPAGAIN;
246
247			sv = POPs;
248
249			if (SvPVX (sv)[0] != MAGIC_R)
250			croak ("Storable format changed, need newer version of Compress::LZF");
251
252			if (ix) /* compress */
253			XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_CR, 0)));
254			else
255			XPUSHs (sv);
256			}
257	root	1.4	else if (sv && IN_RANGE (SvPVX (sv)[0], MAGIC_LO, MAGIC_HI))
258	root	1.1	XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 1))); /* need to prefix only */
259			else if (ix == 2) /* compress always */
260			XPUSHs (sv_2mortal (compress_sv (sv, MAGIC_C, 0)));
261			else /* don't compress */
262			XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));
263
264			void
265			sthaw(sv)
266			SV * sv
267			PROTOTYPE: $
268			PPCODE:
269
270	root	1.4	if (IN_RANGE (SvPV_nolen (sv)[0], MAGIC_LO, MAGIC_HI))
271	root	1.1	{
272			switch (SvPVX (sv)[0])
273			{
274	root	1.4	case MAGIC_undef:
275			XPUSHs (sv_2mortal (NEWSV (0, 0)));
276			break;
277
278	root	1.1	case MAGIC_U:
279			XPUSHs (sv_2mortal (decompress_sv (sv, 0)));
280			break;
281
282			case MAGIC_C:
283			XPUSHs (sv_2mortal (decompress_sv (sv, 1)));
284			break;
285
286			case MAGIC_CR:
287			sv = sv_2mortal (decompress_sv (sv, 1)); /* mortal could be optimized */
288			case MAGIC_R:
289			if (!storable_mstore)
290			need_storable ();
291
292			PUSHMARK (SP);
293			XPUSHs (sv);
294			PUTBACK;
295
296			if (1 != call_sv ((SV *)storable_mretrieve, G_SCALAR))
297			croak ("Storable::mstore didn't return a single scalar");
298
299			SPAGAIN;
300
301	root	1.4	XPUSHs (POPs); /* this is a nop, hope the compiler also knows this */
302	root	1.1
303			break;
304
305			default:
306			croak ("Compress::LZF::sthaw(): invalid data, maybe you need a newer version of Compress::LZF?");
307			}
308			}
309			else
310			XPUSHs (sv_2mortal (SvREFCNT_inc (sv)));