bzlib.c

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         if (k1 != s->k0) { s->k0 = k1; continue; };

         s->state_out_len = 3;
         BZ_GET_SMALL(k1); s->nblock_used++;
         if (s->nblock_used == s->save_nblock+1) continue;
         if (k1 != s->k0) { s->k0 = k1; continue; };

         BZ_GET_SMALL(k1); s->nblock_used++;
         s->state_out_len = ((Int32)k1) + 4;
         BZ_GET_SMALL(s->k0); s->nblock_used++;
      }

   }
}

/*---------------------------------------------------*/
int BZ_API(BZ2_bzDecompress) ( bz_stream *strm )
{
   DState* s;
   if (strm == NULL) return BZ_PARAM_ERROR;
   s = strm->state;
   if (s == NULL) return BZ_PARAM_ERROR;
   if (s->strm != strm) return BZ_PARAM_ERROR;

   while (True) {
      if (s->state == BZ_X_IDLE) return BZ_SEQUENCE_ERROR;
      if (s->state == BZ_X_OUTPUT) {
#ifndef BZ_DECOMPRESS_ONLY
         if (s->smallDecompress)
            unRLE_obuf_to_output_SMALL ( s ); else
            unRLE_obuf_to_output_FAST  ( s );
#else
	 unRLE_obuf_to_output_SMALL ( s );
#endif
         if (s->nblock_used == s->save_nblock+1 && s->state_out_len == 0) {
            BZ_FINALISE_CRC ( s->calculatedBlockCRC );
            if (s->verbosity >= 3)
               VPrintf2 ( " {0x%x, 0x%x}", s->storedBlockCRC,
                          s->calculatedBlockCRC );
            if (s->verbosity >= 2) VPrintf0 ( "]" );
            if (s->calculatedBlockCRC != s->storedBlockCRC)
               return BZ_DATA_ERROR;
            s->calculatedCombinedCRC
               = (s->calculatedCombinedCRC << 1) |
                    (s->calculatedCombinedCRC >> 31);
            s->calculatedCombinedCRC ^= s->calculatedBlockCRC;
            s->state = BZ_X_BLKHDR_1;
         } else {
            return BZ_OK;
         }
      }
      if (s->state >= BZ_X_MAGIC_1) {
         Int32 r = BZ2_decompress ( s );
         if (r == BZ_STREAM_END) {
            if (s->verbosity >= 3)
               VPrintf2 ( "\n    combined CRCs: stored = 0x%x, computed = 0x%x",
                          s->storedCombinedCRC, s->calculatedCombinedCRC );
            if (s->calculatedCombinedCRC != s->storedCombinedCRC)
               return BZ_DATA_ERROR;
            return r;
         }
         if (s->state != BZ_X_OUTPUT) return r;
      }
   }

   AssertH ( 0, 6001 );

   return 0;  /*NOTREACHED*/
}


/*---------------------------------------------------*/
int BZ_API(BZ2_bzDecompressEnd)  ( bz_stream *strm )
{
   DState* s;
   if (strm == NULL) return BZ_PARAM_ERROR;
   s = strm->state;
   if (s == NULL) return BZ_PARAM_ERROR;
   if (s->strm != strm) return BZ_PARAM_ERROR;

   if (s->tt   != NULL) BZFREE(s->tt);
   if (s->ll16 != NULL) BZFREE(s->ll16);
   if (s->ll4  != NULL) BZFREE(s->ll4);

   BZFREE(strm->state);
   strm->state = NULL;

   return BZ_OK;
}


#ifndef BZ_NO_STDIO
/*---------------------------------------------------*/
/*--- File I/O stuff                              ---*/
/*---------------------------------------------------*/

#define BZ_SETERR(eee)                    \
{                                         \
   if (bzerror != NULL) *bzerror = eee;   \
   if (bzf != NULL) bzf->lastErr = eee;   \
}

typedef
   struct {
      FILE*     handle;
      Char      buf[BZ_MAX_UNUSED];
      Int32     bufN;
      Bool      writing;
      bz_stream strm;
      Int32     lastErr;
      Bool      initialisedOk;
   }
   bzFile;


/*---------------------------------------------*/
static Bool myfeof ( FILE* f )
{
   Int32 c = fgetc ( f );
   if (c == EOF) return True;
   ungetc ( c, f );
   return False;
}


/*---------------------------------------------------*/
BZFILE* BZ_API(BZ2_bzWriteOpen)
                    ( int*  bzerror,
                      FILE* f,
                      int   blockSize100k,
                      int   verbosity,
                      int   workFactor )
{
   Int32   ret;
   bzFile* bzf = NULL;

   BZ_SETERR(BZ_OK);

   if (f == NULL ||
       (blockSize100k < 1 || blockSize100k > 9) ||
       (workFactor < 0 || workFactor > 250) ||
       (verbosity < 0 || verbosity > 4))
      { BZ_SETERR(BZ_PARAM_ERROR); return NULL; };

   if (ferror(f))
      { BZ_SETERR(BZ_IO_ERROR); return NULL; };

   bzf = malloc ( sizeof(bzFile) );
   if (bzf == NULL)
      { BZ_SETERR(BZ_MEM_ERROR); return NULL; };

   BZ_SETERR(BZ_OK);
   bzf->initialisedOk = False;
   bzf->bufN          = 0;
   bzf->handle        = f;
   bzf->writing       = True;
   bzf->strm.bzalloc  = NULL;
   bzf->strm.bzfree   = NULL;
   bzf->strm.opaque   = NULL;

   if (workFactor == 0) workFactor = 30;
   ret = BZ2_bzCompressInit ( &(bzf->strm), blockSize100k,
                              verbosity, workFactor );
   if (ret != BZ_OK)
      { BZ_SETERR(ret); free(bzf); return NULL; };

   bzf->strm.avail_in = 0;
   bzf->initialisedOk = True;
   return bzf;
}



/*---------------------------------------------------*/
void BZ_API(BZ2_bzWrite)
             ( int*    bzerror,
               BZFILE* b,
               void*   buf,
               int     len )
{
   Int32 n, n2, ret;
   bzFile* bzf = (bzFile*)b;

   BZ_SETERR(BZ_OK);
   if (bzf == NULL || buf == NULL || len < 0)
      { BZ_SETERR(BZ_PARAM_ERROR); return; };
   if (!(bzf->writing))
      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
   if (ferror(bzf->handle))
      { BZ_SETERR(BZ_IO_ERROR); return; };

   if (len == 0)
      { BZ_SETERR(BZ_OK); return; };

   bzf->strm.avail_in = len;
   bzf->strm.next_in  = buf;

   while (True) {
      bzf->strm.avail_out = BZ_MAX_UNUSED;
      bzf->strm.next_out = bzf->buf;
      ret = BZ2_bzCompress ( &(bzf->strm), BZ_RUN );
      if (ret != BZ_RUN_OK)
         { BZ_SETERR(ret); return; };

      if (bzf->strm.avail_out < BZ_MAX_UNUSED) {
         n = BZ_MAX_UNUSED - bzf->strm.avail_out;
         n2 = fwrite ( (void*)(bzf->buf), sizeof(UChar),
                       n, bzf->handle );
         if (n != n2 || ferror(bzf->handle))
            { BZ_SETERR(BZ_IO_ERROR); return; };
      }

      if (bzf->strm.avail_in == 0)
         { BZ_SETERR(BZ_OK); return; };
   }
}


/*---------------------------------------------------*/
void BZ_API(BZ2_bzWriteClose)
                  ( int*          bzerror,
                    BZFILE*       b,
                    int           abandon,
                    unsigned int* nbytes_in,
                    unsigned int* nbytes_out )
{
   BZ2_bzWriteClose64 ( bzerror, b, abandon,
                        nbytes_in, NULL, nbytes_out, NULL );
}


void BZ_API(BZ2_bzWriteClose64)
                  ( int*          bzerror,
                    BZFILE*       b,
                    int           abandon,
                    unsigned int* nbytes_in_lo32,
                    unsigned int* nbytes_in_hi32,
                    unsigned int* nbytes_out_lo32,
                    unsigned int* nbytes_out_hi32 )
{
   Int32   n, n2, ret;
   bzFile* bzf = (bzFile*)b;

   if (bzf == NULL)
      { BZ_SETERR(BZ_OK); return; };
   if (!(bzf->writing))
      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };
   if (ferror(bzf->handle))
      { BZ_SETERR(BZ_IO_ERROR); return; };

   if (nbytes_in_lo32 != NULL) *nbytes_in_lo32 = 0;
   if (nbytes_in_hi32 != NULL) *nbytes_in_hi32 = 0;
   if (nbytes_out_lo32 != NULL) *nbytes_out_lo32 = 0;
   if (nbytes_out_hi32 != NULL) *nbytes_out_hi32 = 0;

   if ((!abandon) && bzf->lastErr == BZ_OK) {
      while (True) {
         bzf->strm.avail_out = BZ_MAX_UNUSED;
         bzf->strm.next_out = bzf->buf;
         ret = BZ2_bzCompress ( &(bzf->strm), BZ_FINISH );
         if (ret != BZ_FINISH_OK && ret != BZ_STREAM_END)
            { BZ_SETERR(ret); return; };

         if (bzf->strm.avail_out < BZ_MAX_UNUSED) {
            n = BZ_MAX_UNUSED - bzf->strm.avail_out;
            n2 = fwrite ( (void*)(bzf->buf), sizeof(UChar),
                          n, bzf->handle );
            if (n != n2 || ferror(bzf->handle))
               { BZ_SETERR(BZ_IO_ERROR); return; };
         }

         if (ret == BZ_STREAM_END) break;
      }
   }

   if ( !abandon && !ferror ( bzf->handle ) ) {
      fflush ( bzf->handle );
      if (ferror(bzf->handle))
         { BZ_SETERR(BZ_IO_ERROR); return; };
   }

   if (nbytes_in_lo32 != NULL)
      *nbytes_in_lo32 = bzf->strm.total_in_lo32;
   if (nbytes_in_hi32 != NULL)
      *nbytes_in_hi32 = bzf->strm.total_in_hi32;
   if (nbytes_out_lo32 != NULL)
      *nbytes_out_lo32 = bzf->strm.total_out_lo32;
   if (nbytes_out_hi32 != NULL)
      *nbytes_out_hi32 = bzf->strm.total_out_hi32;

   BZ_SETERR(BZ_OK);
   BZ2_bzCompressEnd ( &(bzf->strm) );
   free ( bzf );
}


/*---------------------------------------------------*/
BZFILE* BZ_API(BZ2_bzReadOpen)
                   ( int*  bzerror,
                     FILE* f,
                     int   verbosity,
                     int   small,
                     void* unused,
                     int   nUnused )
{
   bzFile* bzf = NULL;
   int     ret;

   BZ_SETERR(BZ_OK);

   if (f == NULL ||
       (small != 0 && small != 1) ||
       (verbosity < 0 || verbosity > 4) ||
       (unused == NULL && nUnused != 0) ||
       (unused != NULL && (nUnused < 0 || nUnused > BZ_MAX_UNUSED)))
      { BZ_SETERR(BZ_PARAM_ERROR); return NULL; };

   if (ferror(f))
      { BZ_SETERR(BZ_IO_ERROR); return NULL; };

   bzf = malloc ( sizeof(bzFile) );
   if (bzf == NULL)
      { BZ_SETERR(BZ_MEM_ERROR); return NULL; };

   BZ_SETERR(BZ_OK);

   bzf->initialisedOk = False;
   bzf->handle        = f;
   bzf->bufN          = 0;
   bzf->writing       = False;
   bzf->strm.bzalloc  = NULL;
   bzf->strm.bzfree   = NULL;
   bzf->strm.opaque   = NULL;

   while (nUnused > 0) {
      bzf->buf[bzf->bufN] = *((UChar*)(unused)); bzf->bufN++;
      unused = ((void*)( 1 + ((UChar*)(unused))  ));
      nUnused--;
   }

   ret = BZ2_bzDecompressInit ( &(bzf->strm), verbosity, small );
   if (ret != BZ_OK)
      { BZ_SETERR(ret); free(bzf); return NULL; };

   bzf->strm.avail_in = bzf->bufN;
   bzf->strm.next_in  = bzf->buf;

   bzf->initialisedOk = True;
   return bzf;
}


/*---------------------------------------------------*/
void BZ_API(BZ2_bzReadClose) ( int *bzerror, BZFILE *b )
{
   bzFile* bzf = (bzFile*)b;

   BZ_SETERR(BZ_OK);
   if (bzf == NULL)
      { BZ_SETERR(BZ_OK); return; };

   if (bzf->writing)
      { BZ_SETERR(BZ_SEQUENCE_ERROR); return; };

   if (bzf->initialisedOk)
      (void)BZ2_bzDecompressEnd ( &(bzf->strm) );
   free ( bzf );
}


/*---------------------------------------------------*/
int BZ_API(BZ2_bzRead)
           ( int*    bzerror,
             BZFILE* b,
             void*   buf,
             int     len )
{
   Int32   n, ret;
   bzFile* bzf = (bzFile*)b;

   BZ_SETERR(BZ_OK);

   if (bzf == NULL || buf == NULL || len < 0)
      { BZ_SETERR(BZ_PARAM_ERROR); return 0; };

   if (bzf->writing)
      { BZ_SETERR(BZ_SEQUENCE_ERROR); return 0; };

   if (len == 0)
      { BZ_SETERR(BZ_OK); return 0; };

   bzf->strm.avail_out = len;
   bzf->strm.next_out = buf;

   while (True) {