| /* | 
 |  * Copyright (c) 1990-1997 Sam Leffler | 
 |  * Copyright (c) 1991-1997 Silicon Graphics, Inc. | 
 |  * | 
 |  * Permission to use, copy, modify, distribute, and sell this software and | 
 |  * its documentation for any purpose is hereby granted without fee, provided | 
 |  * that (i) the above copyright notices and this permission notice appear in | 
 |  * all copies of the software and related documentation, and (ii) the names of | 
 |  * Sam Leffler and Silicon Graphics may not be used in any advertising or | 
 |  * publicity relating to the software without the specific, prior written | 
 |  * permission of Sam Leffler and Silicon Graphics. | 
 |  * | 
 |  * THE SOFTWARE IS PROVIDED "AS-IS" AND WITHOUT WARRANTY OF ANY KIND, | 
 |  * EXPRESS, IMPLIED OR OTHERWISE, INCLUDING WITHOUT LIMITATION, ANY | 
 |  * WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE. | 
 |  * | 
 |  * IN NO EVENT SHALL SAM LEFFLER OR SILICON GRAPHICS BE LIABLE FOR | 
 |  * ANY SPECIAL, INCIDENTAL, INDIRECT OR CONSEQUENTIAL DAMAGES OF ANY KIND, | 
 |  * OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, | 
 |  * WHETHER OR NOT ADVISED OF THE POSSIBILITY OF DAMAGE, AND ON ANY THEORY OF | 
 |  * LIABILITY, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE | 
 |  * OF THIS SOFTWARE. | 
 |  */ | 
 |  | 
 | #include "tiffiop.h" | 
 | #ifdef CCITT_SUPPORT | 
 | /* | 
 |  * TIFF Library. | 
 |  * | 
 |  * CCITT Group 3 (T.4) and Group 4 (T.6) Compression Support. | 
 |  * | 
 |  * This file contains support for decoding and encoding TIFF | 
 |  * compression algorithms 2, 3, 4, and 32771. | 
 |  * | 
 |  * Decoder support is derived, with permission, from the code | 
 |  * in Frank Cringle's viewfax program; | 
 |  *      Copyright (C) 1990, 1995  Frank D. Cringle. | 
 |  */ | 
 | #include "tif_fax3.h" | 
 | #define G3CODES | 
 | #include "t4.h" | 
 | #include <stdio.h> | 
 |  | 
 | #ifndef EOF_REACHED_COUNT_THRESHOLD | 
 | /* Arbitrary threshold to avoid corrupted single-strip files with extremely | 
 |  * large imageheight to cause apparently endless looping, such as in | 
 |  * https://gitlab.com/libtiff/libtiff/-/issues/583 | 
 |  */ | 
 | #define EOF_REACHED_COUNT_THRESHOLD 8192 | 
 | #endif | 
 |  | 
 | /* | 
 |  * Compression+decompression state blocks are | 
 |  * derived from this ``base state'' block. | 
 |  */ | 
 | typedef struct | 
 | { | 
 |     int rw_mode;        /* O_RDONLY for decode, else encode */ | 
 |     int mode;           /* operating mode */ | 
 |     tmsize_t rowbytes;  /* bytes in a decoded scanline */ | 
 |     uint32_t rowpixels; /* pixels in a scanline */ | 
 |  | 
 |     uint16_t cleanfaxdata; /* CleanFaxData tag */ | 
 |     uint32_t badfaxrun;    /* BadFaxRun tag */ | 
 |     uint32_t badfaxlines;  /* BadFaxLines tag */ | 
 |     uint32_t groupoptions; /* Group 3/4 options tag */ | 
 |  | 
 |     TIFFVGetMethod vgetparent; /* super-class method */ | 
 |     TIFFVSetMethod vsetparent; /* super-class method */ | 
 |     TIFFPrintMethod printdir;  /* super-class method */ | 
 | } Fax3BaseState; | 
 | #define Fax3State(tif) ((Fax3BaseState *)(tif)->tif_data) | 
 |  | 
 | typedef enum | 
 | { | 
 |     G3_1D, | 
 |     G3_2D | 
 | } Ttag; | 
 | typedef struct | 
 | { | 
 |     Fax3BaseState b; | 
 |  | 
 |     /* Decoder state info */ | 
 |     const unsigned char *bitmap; /* bit reversal table */ | 
 |     uint32_t data;               /* current i/o byte/word */ | 
 |     int bit;                     /* current i/o bit in byte */ | 
 |     int EOLcnt;                  /* count of EOL codes recognized */ | 
 |     int eofReachedCount;         /* number of times decode has been called with | 
 |                                     EOF already reached */ | 
 |     TIFFFaxFillFunc fill;        /* fill routine */ | 
 |     uint32_t *runs;              /* b&w runs for current/previous row */ | 
 |     uint32_t nruns;              /* size of the refruns / curruns arrays */ | 
 |     uint32_t *refruns;           /* runs for reference line */ | 
 |     uint32_t *curruns;           /* runs for current line */ | 
 |  | 
 |     /* Encoder state info */ | 
 |     Ttag tag;               /* encoding state */ | 
 |     unsigned char *refline; /* reference line for 2d decoding */ | 
 |     int k;                  /* #rows left that can be 2d encoded */ | 
 |     int maxk;               /* max #rows that can be 2d encoded */ | 
 |  | 
 |     int line; | 
 | } Fax3CodecState; | 
 | #define DecoderState(tif) ((Fax3CodecState *)Fax3State(tif)) | 
 | #define EncoderState(tif) ((Fax3CodecState *)Fax3State(tif)) | 
 |  | 
 | #define is2DEncoding(sp) (sp->b.groupoptions & GROUP3OPT_2DENCODING) | 
 | #define isAligned(p, t) ((((size_t)(p)) & (sizeof(t) - 1)) == 0) | 
 |  | 
 | /* | 
 |  * Group 3 and Group 4 Decoding. | 
 |  */ | 
 |  | 
 | /* | 
 |  * These macros glue the TIFF library state to | 
 |  * the state expected by Frank's decoder. | 
 |  */ | 
 | #define DECLARE_STATE(tif, sp, mod)                                            \ | 
 |     static const char module[] = mod;                                          \ | 
 |     Fax3CodecState *sp = DecoderState(tif);                                    \ | 
 |     int a0;                                   /* reference element */          \ | 
 |     int lastx = sp->b.rowpixels;              /* last element in row */        \ | 
 |     uint32_t BitAcc;                          /* bit accumulator */            \ | 
 |     int BitsAvail;                            /* # valid bits in BitAcc */     \ | 
 |     int RunLength;                            /* length of current run */      \ | 
 |     unsigned char *cp;                        /* next byte of input data */    \ | 
 |     unsigned char *ep;                        /* end of input data */          \ | 
 |     uint32_t *pa;                             /* place to stuff next run */    \ | 
 |     uint32_t *thisrun;                        /* current row's run array */    \ | 
 |     int EOLcnt;                               /* # EOL codes recognized */     \ | 
 |     const unsigned char *bitmap = sp->bitmap; /* input data bit reverser */    \ | 
 |     const TIFFFaxTabEnt *TabEnt | 
 |  | 
 | #define DECLARE_STATE_2D(tif, sp, mod)                                         \ | 
 |     DECLARE_STATE(tif, sp, mod);                                               \ | 
 |     int b1; /* next change on prev line */                                     \ | 
 |     uint32_t                                                                   \ | 
 |         *pb /* next run in reference line */ /*                                \ | 
 |                                               * Load any state that may be     \ | 
 |                                               * changed during decoding.       \ | 
 |                                               */ | 
 | #define CACHE_STATE(tif, sp)                                                   \ | 
 |     do                                                                         \ | 
 |     {                                                                          \ | 
 |         BitAcc = sp->data;                                                     \ | 
 |         BitsAvail = sp->bit;                                                   \ | 
 |         EOLcnt = sp->EOLcnt;                                                   \ | 
 |         cp = (unsigned char *)tif->tif_rawcp;                                  \ | 
 |         ep = cp + tif->tif_rawcc;                                              \ | 
 |     } while (0) | 
 | /* | 
 |  * Save state possibly changed during decoding. | 
 |  */ | 
 | #define UNCACHE_STATE(tif, sp)                                                 \ | 
 |     do                                                                         \ | 
 |     {                                                                          \ | 
 |         sp->bit = BitsAvail;                                                   \ | 
 |         sp->data = BitAcc;                                                     \ | 
 |         sp->EOLcnt = EOLcnt;                                                   \ | 
 |         tif->tif_rawcc -= (tmsize_t)((uint8_t *)cp - tif->tif_rawcp);          \ | 
 |         tif->tif_rawcp = (uint8_t *)cp;                                        \ | 
 |     } while (0) | 
 |  | 
 | /* | 
 |  * Setup state for decoding a strip. | 
 |  */ | 
 | static int Fax3PreDecode(TIFF *tif, uint16_t s) | 
 | { | 
 |     Fax3CodecState *sp = DecoderState(tif); | 
 |  | 
 |     (void)s; | 
 |     assert(sp != NULL); | 
 |     sp->bit = 0; /* force initial read */ | 
 |     sp->data = 0; | 
 |     sp->EOLcnt = 0; /* force initial scan for EOL */ | 
 |     sp->eofReachedCount = 0; | 
 |     /* | 
 |      * Decoder assumes lsb-to-msb bit order.  Note that we select | 
 |      * this here rather than in Fax3SetupState so that viewers can | 
 |      * hold the image open, fiddle with the FillOrder tag value, | 
 |      * and then re-decode the image.  Otherwise they'd need to close | 
 |      * and open the image to get the state reset. | 
 |      */ | 
 |     sp->bitmap = | 
 |         TIFFGetBitRevTable(tif->tif_dir.td_fillorder != FILLORDER_LSB2MSB); | 
 |     sp->curruns = sp->runs; | 
 |     if (sp->refruns) | 
 |     { /* init reference line to white */ | 
 |         sp->refruns = sp->runs + sp->nruns; | 
 |         sp->refruns[0] = (uint32_t)sp->b.rowpixels; | 
 |         sp->refruns[1] = 0; | 
 |     } | 
 |     sp->line = 0; | 
 |     return (1); | 
 | } | 
 |  | 
 | /* | 
 |  * Routine for handling various errors/conditions. | 
 |  * Note how they are "glued into the decoder" by | 
 |  * overriding the definitions used by the decoder. | 
 |  */ | 
 |  | 
 | static void Fax3Unexpected(const char *module, TIFF *tif, uint32_t line, | 
 |                            uint32_t a0) | 
 | { | 
 |     TIFFErrorExtR(tif, module, | 
 |                   "Bad code word at line %" PRIu32 " of %s %" PRIu32 | 
 |                   " (x %" PRIu32 ")", | 
 |                   line, isTiled(tif) ? "tile" : "strip", | 
 |                   (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip), a0); | 
 | } | 
 | #define unexpected(table, a0) Fax3Unexpected(module, tif, sp->line, a0) | 
 |  | 
 | static void Fax3Extension(const char *module, TIFF *tif, uint32_t line, | 
 |                           uint32_t a0) | 
 | { | 
 |     TIFFErrorExtR(tif, module, | 
 |                   "Uncompressed data (not supported) at line %" PRIu32 | 
 |                   " of %s %" PRIu32 " (x %" PRIu32 ")", | 
 |                   line, isTiled(tif) ? "tile" : "strip", | 
 |                   (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip), a0); | 
 | } | 
 | #define extension(a0) Fax3Extension(module, tif, sp->line, a0) | 
 |  | 
 | static void Fax3BadLength(const char *module, TIFF *tif, uint32_t line, | 
 |                           uint32_t a0, uint32_t lastx) | 
 | { | 
 |     TIFFWarningExtR(tif, module, | 
 |                     "%s at line %" PRIu32 " of %s %" PRIu32 " (got %" PRIu32 | 
 |                     ", expected %" PRIu32 ")", | 
 |                     a0 < lastx ? "Premature EOL" : "Line length mismatch", line, | 
 |                     isTiled(tif) ? "tile" : "strip", | 
 |                     (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip), a0, | 
 |                     lastx); | 
 | } | 
 | #define badlength(a0, lastx) Fax3BadLength(module, tif, sp->line, a0, lastx) | 
 |  | 
 | static void Fax3PrematureEOF(const char *module, TIFF *tif, uint32_t line, | 
 |                              uint32_t a0) | 
 | { | 
 |     TIFFWarningExtR(tif, module, | 
 |                     "Premature EOF at line %" PRIu32 " of %s %" PRIu32 | 
 |                     " (x %" PRIu32 ")", | 
 |                     line, isTiled(tif) ? "tile" : "strip", | 
 |                     (isTiled(tif) ? tif->tif_curtile : tif->tif_curstrip), a0); | 
 | } | 
 | #define prematureEOF(a0)                                                       \ | 
 |     do                                                                         \ | 
 |     {                                                                          \ | 
 |         Fax3PrematureEOF(module, tif, sp->line, a0);                           \ | 
 |         ++sp->eofReachedCount;                                                 \ | 
 |     } while (0) | 
 |  | 
 | #define Nop | 
 |  | 
 | /** | 
 |  * Decode the requested amount of G3 1D-encoded data. | 
 |  * @param buf destination buffer | 
 |  * @param occ available bytes in destination buffer | 
 |  * @param s number of planes (ignored) | 
 |  * @returns 1 for success, -1 in case of error | 
 |  */ | 
 | static int Fax3Decode1D(TIFF *tif, uint8_t *buf, tmsize_t occ, uint16_t s) | 
 | { | 
 |     DECLARE_STATE(tif, sp, "Fax3Decode1D"); | 
 |     (void)s; | 
 |     if (occ % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be read"); | 
 |         return (-1); | 
 |     } | 
 |     if (sp->eofReachedCount >= EOF_REACHED_COUNT_THRESHOLD) | 
 |     { | 
 |         TIFFErrorExtR( | 
 |             tif, module, | 
 |             "End of file has already been reached %d times within that strip", | 
 |             sp->eofReachedCount); | 
 |         return (-1); | 
 |     } | 
 |     CACHE_STATE(tif, sp); | 
 |     thisrun = sp->curruns; | 
 |     while (occ > 0) | 
 |     { | 
 |         a0 = 0; | 
 |         RunLength = 0; | 
 |         pa = thisrun; | 
 | #ifdef FAX3_DEBUG | 
 |         printf("\nBitAcc=%08" PRIX32 ", BitsAvail = %d\n", BitAcc, BitsAvail); | 
 |         printf("-------------------- %" PRIu32 "\n", tif->tif_row); | 
 |         fflush(stdout); | 
 | #endif | 
 |         SYNC_EOL(EOF1D); | 
 |         EXPAND1D(EOF1Da); | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         buf += sp->b.rowbytes; | 
 |         occ -= sp->b.rowbytes; | 
 |         sp->line++; | 
 |         continue; | 
 |     EOF1D: /* premature EOF */ | 
 |         CLEANUP_RUNS(); | 
 |     EOF1Da: /* premature EOF */ | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         UNCACHE_STATE(tif, sp); | 
 |         return (-1); | 
 |     } | 
 |     UNCACHE_STATE(tif, sp); | 
 |     return (1); | 
 | } | 
 |  | 
 | #define SWAP(t, a, b)                                                          \ | 
 |     {                                                                          \ | 
 |         t x;                                                                   \ | 
 |         x = (a);                                                               \ | 
 |         (a) = (b);                                                             \ | 
 |         (b) = x;                                                               \ | 
 |     } | 
 | /* | 
 |  * Decode the requested amount of G3 2D-encoded data. | 
 |  */ | 
 | static int Fax3Decode2D(TIFF *tif, uint8_t *buf, tmsize_t occ, uint16_t s) | 
 | { | 
 |     DECLARE_STATE_2D(tif, sp, "Fax3Decode2D"); | 
 |     int is1D; /* current line is 1d/2d-encoded */ | 
 |     (void)s; | 
 |     if (occ % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be read"); | 
 |         return (-1); | 
 |     } | 
 |     if (sp->eofReachedCount >= EOF_REACHED_COUNT_THRESHOLD) | 
 |     { | 
 |         TIFFErrorExtR( | 
 |             tif, module, | 
 |             "End of file has already been reached %d times within that strip", | 
 |             sp->eofReachedCount); | 
 |         return (-1); | 
 |     } | 
 |     CACHE_STATE(tif, sp); | 
 |     while (occ > 0) | 
 |     { | 
 |         a0 = 0; | 
 |         RunLength = 0; | 
 |         pa = thisrun = sp->curruns; | 
 | #ifdef FAX3_DEBUG | 
 |         printf("\nBitAcc=%08" PRIX32 ", BitsAvail = %d EOLcnt = %d", BitAcc, | 
 |                BitsAvail, EOLcnt); | 
 | #endif | 
 |         SYNC_EOL(EOF2D); | 
 |         NeedBits8(1, EOF2D); | 
 |         is1D = GetBits(1); /* 1D/2D-encoding tag bit */ | 
 |         ClrBits(1); | 
 | #ifdef FAX3_DEBUG | 
 |         printf(" %s\n-------------------- %" PRIu32 "\n", is1D ? "1D" : "2D", | 
 |                tif->tif_row); | 
 |         fflush(stdout); | 
 | #endif | 
 |         pb = sp->refruns; | 
 |         b1 = *pb++; | 
 |         if (is1D) | 
 |             EXPAND1D(EOF2Da); | 
 |         else | 
 |             EXPAND2D(EOF2Da); | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         if (pa < thisrun + sp->nruns) | 
 |         { | 
 |             SETVALUE(0); /* imaginary change for reference */ | 
 |         } | 
 |         SWAP(uint32_t *, sp->curruns, sp->refruns); | 
 |         buf += sp->b.rowbytes; | 
 |         occ -= sp->b.rowbytes; | 
 |         sp->line++; | 
 |         continue; | 
 |     EOF2D: /* premature EOF */ | 
 |         CLEANUP_RUNS(); | 
 |     EOF2Da: /* premature EOF */ | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         UNCACHE_STATE(tif, sp); | 
 |         return (-1); | 
 |     } | 
 |     UNCACHE_STATE(tif, sp); | 
 |     return (1); | 
 | } | 
 | #undef SWAP | 
 |  | 
 | #define FILL(n, cp)                                                            \ | 
 |     for (int32_t ifill = 0; ifill < (n); ++ifill)                              \ | 
 |     {                                                                          \ | 
 |         (cp)[ifill] = 0xff;                                                    \ | 
 |     }                                                                          \ | 
 |     (cp) += (n); | 
 |  | 
 | #define ZERO(n, cp)                                                            \ | 
 |     for (int32_t izero = 0; izero < (n); ++izero)                              \ | 
 |     {                                                                          \ | 
 |         (cp)[izero] = 0;                                                       \ | 
 |     }                                                                          \ | 
 |     (cp) += (n); | 
 |  | 
 | /* | 
 |  * Bit-fill a row according to the white/black | 
 |  * runs generated during G3/G4 decoding. | 
 |  */ | 
 | void _TIFFFax3fillruns(unsigned char *buf, uint32_t *runs, uint32_t *erun, | 
 |                        uint32_t lastx) | 
 | { | 
 |     static const unsigned char _fillmasks[] = {0x00, 0x80, 0xc0, 0xe0, 0xf0, | 
 |                                                0xf8, 0xfc, 0xfe, 0xff}; | 
 |     unsigned char *cp; | 
 |     uint32_t x, bx, run; | 
 |     int32_t n, nw; | 
 |     int64_t *lp; | 
 |  | 
 |     if ((erun - runs) & 1) | 
 |         *erun++ = 0; | 
 |     x = 0; | 
 |     for (; runs < erun; runs += 2) | 
 |     { | 
 |         run = runs[0]; | 
 |         if (x + run > lastx || run > lastx) | 
 |             run = runs[0] = (uint32_t)(lastx - x); | 
 |         if (run) | 
 |         { | 
 |             cp = buf + (x >> 3); | 
 |             bx = x & 7; | 
 |             if (run > 8 - bx) | 
 |             { | 
 |                 if (bx) | 
 |                 { /* align to byte boundary */ | 
 |                     *cp++ &= 0xff << (8 - bx); | 
 |                     run -= 8 - bx; | 
 |                 } | 
 |                 if ((n = run >> 3) != 0) | 
 |                 { /* multiple bytes to fill */ | 
 |                     if ((n / sizeof(int64_t)) > 1) | 
 |                     { | 
 |                         /* | 
 |                          * Align to int64_tword boundary and fill. | 
 |                          */ | 
 |                         for (; n && !isAligned(cp, int64_t); n--) | 
 |                             *cp++ = 0x00; | 
 |                         lp = (int64_t *)cp; | 
 |                         nw = (int32_t)(n / sizeof(int64_t)); | 
 |                         n -= nw * sizeof(int64_t); | 
 |                         do | 
 |                         { | 
 |                             *lp++ = 0L; | 
 |                         } while (--nw); | 
 |                         cp = (unsigned char *)lp; | 
 |                     } | 
 |                     ZERO(n, cp); | 
 |                     run &= 7; | 
 |                 } | 
 |                 if (run) | 
 |                     cp[0] &= 0xff >> run; | 
 |             } | 
 |             else | 
 |                 cp[0] &= ~(_fillmasks[run] >> bx); | 
 |             x += runs[0]; | 
 |         } | 
 |         run = runs[1]; | 
 |         if (x + run > lastx || run > lastx) | 
 |             run = runs[1] = lastx - x; | 
 |         if (run) | 
 |         { | 
 |             cp = buf + (x >> 3); | 
 |             bx = x & 7; | 
 |             if (run > 8 - bx) | 
 |             { | 
 |                 if (bx) | 
 |                 { /* align to byte boundary */ | 
 |                     *cp++ |= 0xff >> bx; | 
 |                     run -= 8 - bx; | 
 |                 } | 
 |                 if ((n = run >> 3) != 0) | 
 |                 { /* multiple bytes to fill */ | 
 |                     if ((n / sizeof(int64_t)) > 1) | 
 |                     { | 
 |                         /* | 
 |                          * Align to int64_t boundary and fill. | 
 |                          */ | 
 |                         for (; n && !isAligned(cp, int64_t); n--) | 
 |                             *cp++ = 0xff; | 
 |                         lp = (int64_t *)cp; | 
 |                         nw = (int32_t)(n / sizeof(int64_t)); | 
 |                         n -= nw * sizeof(int64_t); | 
 |                         do | 
 |                         { | 
 |                             *lp++ = -1L; | 
 |                         } while (--nw); | 
 |                         cp = (unsigned char *)lp; | 
 |                     } | 
 |                     FILL(n, cp); | 
 |                     run &= 7; | 
 |                 } | 
 |                 /* Explicit 0xff masking to make icc -check=conversions happy */ | 
 |                 if (run) | 
 |                     cp[0] = (unsigned char)((cp[0] | (0xff00 >> run)) & 0xff); | 
 |             } | 
 |             else | 
 |                 cp[0] |= _fillmasks[run] >> bx; | 
 |             x += runs[1]; | 
 |         } | 
 |     } | 
 |     assert(x == lastx); | 
 | } | 
 | #undef ZERO | 
 | #undef FILL | 
 |  | 
 | static int Fax3FixupTags(TIFF *tif) | 
 | { | 
 |     (void)tif; | 
 |     return (1); | 
 | } | 
 |  | 
 | /* | 
 |  * Setup G3/G4-related compression/decompression state | 
 |  * before data is processed.  This routine is called once | 
 |  * per image -- it sets up different state based on whether | 
 |  * or not decoding or encoding is being done and whether | 
 |  * 1D- or 2D-encoded data is involved. | 
 |  */ | 
 | static int Fax3SetupState(TIFF *tif) | 
 | { | 
 |     static const char module[] = "Fax3SetupState"; | 
 |     TIFFDirectory *td = &tif->tif_dir; | 
 |     Fax3BaseState *sp = Fax3State(tif); | 
 |     int needsRefLine; | 
 |     Fax3CodecState *dsp = (Fax3CodecState *)Fax3State(tif); | 
 |     tmsize_t rowbytes; | 
 |     uint32_t rowpixels; | 
 |  | 
 |     if (td->td_bitspersample != 1) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, | 
 |                       "Bits/sample must be 1 for Group 3/4 encoding/decoding"); | 
 |         return (0); | 
 |     } | 
 |     /* | 
 |      * Calculate the scanline/tile widths. | 
 |      */ | 
 |     if (isTiled(tif)) | 
 |     { | 
 |         rowbytes = TIFFTileRowSize(tif); | 
 |         rowpixels = td->td_tilewidth; | 
 |     } | 
 |     else | 
 |     { | 
 |         rowbytes = TIFFScanlineSize(tif); | 
 |         rowpixels = td->td_imagewidth; | 
 |     } | 
 |     if ((int64_t)rowbytes < ((int64_t)rowpixels + 7) / 8) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, | 
 |                       "Inconsistent number of bytes per row : rowbytes=%" PRId64 | 
 |                       " rowpixels=%" PRIu32, | 
 |                       (int64_t)rowbytes, rowpixels); | 
 |         return (0); | 
 |     } | 
 |     sp->rowbytes = rowbytes; | 
 |     sp->rowpixels = rowpixels; | 
 |     /* | 
 |      * Allocate any additional space required for decoding/encoding. | 
 |      */ | 
 |     needsRefLine = ((sp->groupoptions & GROUP3OPT_2DENCODING) || | 
 |                     td->td_compression == COMPRESSION_CCITTFAX4); | 
 |  | 
 |     /* | 
 |       Assure that allocation computations do not overflow. | 
 |  | 
 |       TIFFroundup and TIFFSafeMultiply return zero on integer overflow | 
 |     */ | 
 |     if (dsp->runs != NULL) | 
 |     { | 
 |         _TIFFfreeExt(tif, dsp->runs); | 
 |         dsp->runs = (uint32_t *)NULL; | 
 |     } | 
 |     dsp->nruns = TIFFroundup_32(rowpixels + 1, 32); | 
 |     if (needsRefLine) | 
 |     { | 
 |         dsp->nruns = TIFFSafeMultiply(uint32_t, dsp->nruns, 2); | 
 |     } | 
 |     if ((dsp->nruns == 0) || (TIFFSafeMultiply(uint32_t, dsp->nruns, 2) == 0)) | 
 |     { | 
 |         TIFFErrorExtR(tif, tif->tif_name, | 
 |                       "Row pixels integer overflow (rowpixels %" PRIu32 ")", | 
 |                       rowpixels); | 
 |         return (0); | 
 |     } | 
 |     dsp->runs = (uint32_t *)_TIFFCheckMalloc( | 
 |         tif, TIFFSafeMultiply(uint32_t, dsp->nruns, 2), sizeof(uint32_t), | 
 |         "for Group 3/4 run arrays"); | 
 |     if (dsp->runs == NULL) | 
 |         return (0); | 
 |     memset(dsp->runs, 0, | 
 |            TIFFSafeMultiply(uint32_t, dsp->nruns, 2) * sizeof(uint32_t)); | 
 |     dsp->curruns = dsp->runs; | 
 |     if (needsRefLine) | 
 |         dsp->refruns = dsp->runs + dsp->nruns; | 
 |     else | 
 |         dsp->refruns = NULL; | 
 |     if (td->td_compression == COMPRESSION_CCITTFAX3 && is2DEncoding(dsp)) | 
 |     { /* NB: default is 1D routine */ | 
 |         tif->tif_decoderow = Fax3Decode2D; | 
 |         tif->tif_decodestrip = Fax3Decode2D; | 
 |         tif->tif_decodetile = Fax3Decode2D; | 
 |     } | 
 |  | 
 |     if (needsRefLine) | 
 |     { /* 2d encoding */ | 
 |         Fax3CodecState *esp = EncoderState(tif); | 
 |         /* | 
 |          * 2d encoding requires a scanline | 
 |          * buffer for the ``reference line''; the | 
 |          * scanline against which delta encoding | 
 |          * is referenced.  The reference line must | 
 |          * be initialized to be ``white'' (done elsewhere). | 
 |          */ | 
 |         if (esp->refline != NULL) | 
 |         { | 
 |             _TIFFfreeExt(tif, esp->refline); | 
 |         } | 
 |         esp->refline = (unsigned char *)_TIFFmallocExt(tif, rowbytes); | 
 |         if (esp->refline == NULL) | 
 |         { | 
 |             TIFFErrorExtR(tif, module, "No space for Group 3/4 reference line"); | 
 |             return (0); | 
 |         } | 
 |     } | 
 |     else /* 1d encoding */ | 
 |         EncoderState(tif)->refline = NULL; | 
 |  | 
 |     return (1); | 
 | } | 
 |  | 
 | /* | 
 |  * CCITT Group 3 FAX Encoding. | 
 |  */ | 
 |  | 
 | #define Fax3FlushBits(tif, sp)                                                 \ | 
 |     {                                                                          \ | 
 |         if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)                        \ | 
 |         {                                                                      \ | 
 |             if (!TIFFFlushData1(tif))                                          \ | 
 |                 return 0;                                                      \ | 
 |         }                                                                      \ | 
 |         *(tif)->tif_rawcp++ = (uint8_t)(sp)->data;                             \ | 
 |         (tif)->tif_rawcc++;                                                    \ | 
 |         (sp)->data = 0, (sp)->bit = 8;                                         \ | 
 |     } | 
 | #define _FlushBits(tif)                                                        \ | 
 |     {                                                                          \ | 
 |         if ((tif)->tif_rawcc >= (tif)->tif_rawdatasize)                        \ | 
 |         {                                                                      \ | 
 |             if (!TIFFFlushData1(tif))                                          \ | 
 |                 return 0;                                                      \ | 
 |         }                                                                      \ | 
 |         *(tif)->tif_rawcp++ = (uint8_t)data;                                   \ | 
 |         (tif)->tif_rawcc++;                                                    \ | 
 |         data = 0, bit = 8;                                                     \ | 
 |     } | 
 | static const int _msbmask[9] = {0x00, 0x01, 0x03, 0x07, 0x0f, | 
 |                                 0x1f, 0x3f, 0x7f, 0xff}; | 
 | #define _PutBits(tif, bits, length)                                            \ | 
 |     {                                                                          \ | 
 |         while (length > bit)                                                   \ | 
 |         {                                                                      \ | 
 |             data |= bits >> (length - bit);                                    \ | 
 |             length -= bit;                                                     \ | 
 |             _FlushBits(tif);                                                   \ | 
 |         }                                                                      \ | 
 |         assert(length < 9);                                                    \ | 
 |         data |= (bits & _msbmask[length]) << (bit - length);                   \ | 
 |         bit -= length;                                                         \ | 
 |         if (bit == 0)                                                          \ | 
 |             _FlushBits(tif);                                                   \ | 
 |     } | 
 |  | 
 | /* | 
 |  * Write a variable-length bit-value to | 
 |  * the output stream.  Values are | 
 |  * assumed to be at most 16 bits. | 
 |  */ | 
 | static int Fax3PutBits(TIFF *tif, unsigned int bits, unsigned int length) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     unsigned int bit = sp->bit; | 
 |     int data = sp->data; | 
 |  | 
 |     _PutBits(tif, bits, length); | 
 |  | 
 |     sp->data = data; | 
 |     sp->bit = bit; | 
 |     return 1; | 
 | } | 
 |  | 
 | /* | 
 |  * Write a code to the output stream. | 
 |  */ | 
 | #define putcode(tif, te) Fax3PutBits(tif, (te)->code, (te)->length) | 
 |  | 
 | #ifdef FAX3_DEBUG | 
 | #define DEBUG_COLOR(w) (tab == TIFFFaxWhiteCodes ? w "W" : w "B") | 
 | #define DEBUG_PRINT(what, len)                                                 \ | 
 |     {                                                                          \ | 
 |         int t;                                                                 \ | 
 |         printf("%08" PRIX32 "/%-2d: %s%5d\t", data, bit, DEBUG_COLOR(what),    \ | 
 |                len);                                                           \ | 
 |         for (t = length - 1; t >= 0; t--)                                      \ | 
 |             putchar(code & (1 << t) ? '1' : '0');                              \ | 
 |         putchar('\n');                                                         \ | 
 |     } | 
 | #endif | 
 |  | 
 | /* | 
 |  * Write the sequence of codes that describes | 
 |  * the specified span of zero's or one's.  The | 
 |  * appropriate table that holds the make-up and | 
 |  * terminating codes is supplied. | 
 |  */ | 
 | static int putspan(TIFF *tif, int32_t span, const tableentry *tab) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     unsigned int bit = sp->bit; | 
 |     int data = sp->data; | 
 |     unsigned int code, length; | 
 |  | 
 |     while (span >= 2624) | 
 |     { | 
 |         const tableentry *te = &tab[63 + (2560 >> 6)]; | 
 |         code = te->code; | 
 |         length = te->length; | 
 | #ifdef FAX3_DEBUG | 
 |         DEBUG_PRINT("MakeUp", te->runlen); | 
 | #endif | 
 |         _PutBits(tif, code, length); | 
 |         span -= te->runlen; | 
 |     } | 
 |     if (span >= 64) | 
 |     { | 
 |         const tableentry *te = &tab[63 + (span >> 6)]; | 
 |         assert(te->runlen == 64 * (span >> 6)); | 
 |         code = te->code; | 
 |         length = te->length; | 
 | #ifdef FAX3_DEBUG | 
 |         DEBUG_PRINT("MakeUp", te->runlen); | 
 | #endif | 
 |         _PutBits(tif, code, length); | 
 |         span -= te->runlen; | 
 |     } | 
 |     code = tab[span].code; | 
 |     length = tab[span].length; | 
 | #ifdef FAX3_DEBUG | 
 |     DEBUG_PRINT("  Term", tab[span].runlen); | 
 | #endif | 
 |     _PutBits(tif, code, length); | 
 |  | 
 |     sp->data = data; | 
 |     sp->bit = bit; | 
 |  | 
 |     return 1; | 
 | } | 
 |  | 
 | /* | 
 |  * Write an EOL code to the output stream.  The zero-fill | 
 |  * logic for byte-aligning encoded scanlines is handled | 
 |  * here.  We also handle writing the tag bit for the next | 
 |  * scanline when doing 2d encoding. | 
 |  */ | 
 | static int Fax3PutEOL(TIFF *tif) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     unsigned int bit = sp->bit; | 
 |     int data = sp->data; | 
 |     unsigned int code, length, tparm; | 
 |  | 
 |     if (sp->b.groupoptions & GROUP3OPT_FILLBITS) | 
 |     { | 
 |         /* | 
 |          * Force bit alignment so EOL will terminate on | 
 |          * a byte boundary.  That is, force the bit alignment | 
 |          * to 16-12 = 4 before putting out the EOL code. | 
 |          */ | 
 |         int align = 8 - 4; | 
 |         if (align != sp->bit) | 
 |         { | 
 |             if (align > sp->bit) | 
 |                 align = sp->bit + (8 - align); | 
 |             else | 
 |                 align = sp->bit - align; | 
 |             tparm = align; | 
 |             _PutBits(tif, 0, tparm); | 
 |         } | 
 |     } | 
 |     code = EOL; | 
 |     length = 12; | 
 |     if (is2DEncoding(sp)) | 
 |     { | 
 |         code = (code << 1) | (sp->tag == G3_1D); | 
 |         length++; | 
 |     } | 
 |     _PutBits(tif, code, length); | 
 |  | 
 |     sp->data = data; | 
 |     sp->bit = bit; | 
 |  | 
 |     return 1; | 
 | } | 
 |  | 
 | /* | 
 |  * Reset encoding state at the start of a strip. | 
 |  */ | 
 | static int Fax3PreEncode(TIFF *tif, uint16_t s) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |  | 
 |     (void)s; | 
 |     assert(sp != NULL); | 
 |     sp->bit = 8; | 
 |     sp->data = 0; | 
 |     sp->tag = G3_1D; | 
 |     /* | 
 |      * This is necessary for Group 4; otherwise it isn't | 
 |      * needed because the first scanline of each strip ends | 
 |      * up being copied into the refline. | 
 |      */ | 
 |     if (sp->refline) | 
 |         _TIFFmemset(sp->refline, 0x00, sp->b.rowbytes); | 
 |     if (is2DEncoding(sp)) | 
 |     { | 
 |         float res = tif->tif_dir.td_yresolution; | 
 |         /* | 
 |          * The CCITT spec says that when doing 2d encoding, you | 
 |          * should only do it on K consecutive scanlines, where K | 
 |          * depends on the resolution of the image being encoded | 
 |          * (2 for <= 200 lpi, 4 for > 200 lpi).  Since the directory | 
 |          * code initializes td_yresolution to 0, this code will | 
 |          * select a K of 2 unless the YResolution tag is set | 
 |          * appropriately.  (Note also that we fudge a little here | 
 |          * and use 150 lpi to avoid problems with units conversion.) | 
 |          */ | 
 |         if (tif->tif_dir.td_resolutionunit == RESUNIT_CENTIMETER) | 
 |             res *= 2.54f; /* convert to inches */ | 
 |         sp->maxk = (res > 150 ? 4 : 2); | 
 |         sp->k = sp->maxk - 1; | 
 |     } | 
 |     else | 
 |         sp->k = sp->maxk = 0; | 
 |     sp->line = 0; | 
 |     return (1); | 
 | } | 
 |  | 
 | static const unsigned char zeroruns[256] = { | 
 |     8, 7, 6, 6, 5, 5, 5, 5, 4, 4, 4, 4, 4, 4, 4, 4, /* 0x00 - 0x0f */ | 
 |     3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 0x10 - 0x1f */ | 
 |     2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 0x20 - 0x2f */ | 
 |     2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 0x30 - 0x3f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x40 - 0x4f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x50 - 0x5f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x60 - 0x6f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x70 - 0x7f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x80 - 0x8f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x90 - 0x9f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xa0 - 0xaf */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xb0 - 0xbf */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xc0 - 0xcf */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xd0 - 0xdf */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xe0 - 0xef */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0xf0 - 0xff */ | 
 | }; | 
 | static const unsigned char oneruns[256] = { | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x00 - 0x0f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x10 - 0x1f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x20 - 0x2f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x30 - 0x3f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x40 - 0x4f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x50 - 0x5f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x60 - 0x6f */ | 
 |     0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, /* 0x70 - 0x7f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x80 - 0x8f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0x90 - 0x9f */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0xa0 - 0xaf */ | 
 |     1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, /* 0xb0 - 0xbf */ | 
 |     2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 0xc0 - 0xcf */ | 
 |     2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, /* 0xd0 - 0xdf */ | 
 |     3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, /* 0xe0 - 0xef */ | 
 |     4, 4, 4, 4, 4, 4, 4, 4, 5, 5, 5, 5, 6, 6, 7, 8, /* 0xf0 - 0xff */ | 
 | }; | 
 |  | 
 | /* | 
 |  * Find a span of ones or zeros using the supplied | 
 |  * table.  The ``base'' of the bit string is supplied | 
 |  * along with the start+end bit indices. | 
 |  */ | 
 | static inline int32_t find0span(unsigned char *bp, int32_t bs, int32_t be) | 
 | { | 
 |     int32_t bits = be - bs; | 
 |     int32_t n, span; | 
 |  | 
 |     bp += bs >> 3; | 
 |     /* | 
 |      * Check partial byte on lhs. | 
 |      */ | 
 |     if (bits > 0 && (n = (bs & 7)) != 0) | 
 |     { | 
 |         span = zeroruns[(*bp << n) & 0xff]; | 
 |         if (span > 8 - n) /* table value too generous */ | 
 |             span = 8 - n; | 
 |         if (span > bits) /* constrain span to bit range */ | 
 |             span = bits; | 
 |         if (n + span < 8) /* doesn't extend to edge of byte */ | 
 |             return (span); | 
 |         bits -= span; | 
 |         bp++; | 
 |     } | 
 |     else | 
 |         span = 0; | 
 |     if (bits >= (int32_t)(2 * 8 * sizeof(int64_t))) | 
 |     { | 
 |         int64_t *lp; | 
 |         /* | 
 |          * Align to int64_t boundary and check int64_t words. | 
 |          */ | 
 |         while (!isAligned(bp, int64_t)) | 
 |         { | 
 |             if (*bp != 0x00) | 
 |                 return (span + zeroruns[*bp]); | 
 |             span += 8; | 
 |             bits -= 8; | 
 |             bp++; | 
 |         } | 
 |         lp = (int64_t *)bp; | 
 |         while ((bits >= (int32_t)(8 * sizeof(int64_t))) && (0 == *lp)) | 
 |         { | 
 |             span += 8 * sizeof(int64_t); | 
 |             bits -= 8 * sizeof(int64_t); | 
 |             lp++; | 
 |         } | 
 |         bp = (unsigned char *)lp; | 
 |     } | 
 |     /* | 
 |      * Scan full bytes for all 0's. | 
 |      */ | 
 |     while (bits >= 8) | 
 |     { | 
 |         if (*bp != 0x00) /* end of run */ | 
 |             return (span + zeroruns[*bp]); | 
 |         span += 8; | 
 |         bits -= 8; | 
 |         bp++; | 
 |     } | 
 |     /* | 
 |      * Check partial byte on rhs. | 
 |      */ | 
 |     if (bits > 0) | 
 |     { | 
 |         n = zeroruns[*bp]; | 
 |         span += (n > bits ? bits : n); | 
 |     } | 
 |     return (span); | 
 | } | 
 |  | 
 | static inline int32_t find1span(unsigned char *bp, int32_t bs, int32_t be) | 
 | { | 
 |     int32_t bits = be - bs; | 
 |     int32_t n, span; | 
 |  | 
 |     bp += bs >> 3; | 
 |     /* | 
 |      * Check partial byte on lhs. | 
 |      */ | 
 |     if (bits > 0 && (n = (bs & 7)) != 0) | 
 |     { | 
 |         span = oneruns[(*bp << n) & 0xff]; | 
 |         if (span > 8 - n) /* table value too generous */ | 
 |             span = 8 - n; | 
 |         if (span > bits) /* constrain span to bit range */ | 
 |             span = bits; | 
 |         if (n + span < 8) /* doesn't extend to edge of byte */ | 
 |             return (span); | 
 |         bits -= span; | 
 |         bp++; | 
 |     } | 
 |     else | 
 |         span = 0; | 
 |     if (bits >= (int32_t)(2 * 8 * sizeof(int64_t))) | 
 |     { | 
 |         int64_t *lp; | 
 |         /* | 
 |          * Align to int64_t boundary and check int64_t words. | 
 |          */ | 
 |         while (!isAligned(bp, int64_t)) | 
 |         { | 
 |             if (*bp != 0xff) | 
 |                 return (span + oneruns[*bp]); | 
 |             span += 8; | 
 |             bits -= 8; | 
 |             bp++; | 
 |         } | 
 |         lp = (int64_t *)bp; | 
 |         while ((bits >= (int32_t)(8 * sizeof(int64_t))) && | 
 |                (~((uint64_t)0) == (uint64_t)*lp)) | 
 |         { | 
 |             span += 8 * sizeof(int64_t); | 
 |             bits -= 8 * sizeof(int64_t); | 
 |             lp++; | 
 |         } | 
 |         bp = (unsigned char *)lp; | 
 |     } | 
 |     /* | 
 |      * Scan full bytes for all 1's. | 
 |      */ | 
 |     while (bits >= 8) | 
 |     { | 
 |         if (*bp != 0xff) /* end of run */ | 
 |             return (span + oneruns[*bp]); | 
 |         span += 8; | 
 |         bits -= 8; | 
 |         bp++; | 
 |     } | 
 |     /* | 
 |      * Check partial byte on rhs. | 
 |      */ | 
 |     if (bits > 0) | 
 |     { | 
 |         n = oneruns[*bp]; | 
 |         span += (n > bits ? bits : n); | 
 |     } | 
 |     return (span); | 
 | } | 
 |  | 
 | /* | 
 |  * Return the offset of the next bit in the range | 
 |  * [bs..be] that is different from the specified | 
 |  * color.  The end, be, is returned if no such bit | 
 |  * exists. | 
 |  */ | 
 | #define finddiff(_cp, _bs, _be, _color)                                        \ | 
 |     (_bs + (_color ? find1span(_cp, _bs, _be) : find0span(_cp, _bs, _be))) | 
 | /* | 
 |  * Like finddiff, but also check the starting bit | 
 |  * against the end in case start > end. | 
 |  */ | 
 | #define finddiff2(_cp, _bs, _be, _color)                                       \ | 
 |     (_bs < _be ? finddiff(_cp, _bs, _be, _color) : _be) | 
 |  | 
 | /* | 
 |  * 1d-encode a row of pixels.  The encoding is | 
 |  * a sequence of all-white or all-black spans | 
 |  * of pixels encoded with Huffman codes. | 
 |  */ | 
 | static int Fax3Encode1DRow(TIFF *tif, unsigned char *bp, uint32_t bits) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     int32_t span; | 
 |     uint32_t bs = 0; | 
 |  | 
 |     for (;;) | 
 |     { | 
 |         span = find0span(bp, bs, bits); /* white span */ | 
 |         if (!putspan(tif, span, TIFFFaxWhiteCodes)) | 
 |             return 0; | 
 |         bs += span; | 
 |         if (bs >= bits) | 
 |             break; | 
 |         span = find1span(bp, bs, bits); /* black span */ | 
 |         if (!putspan(tif, span, TIFFFaxBlackCodes)) | 
 |             return 0; | 
 |         bs += span; | 
 |         if (bs >= bits) | 
 |             break; | 
 |     } | 
 |     if (sp->b.mode & (FAXMODE_BYTEALIGN | FAXMODE_WORDALIGN)) | 
 |     { | 
 |         if (sp->bit != 8) /* byte-align */ | 
 |             Fax3FlushBits(tif, sp); | 
 |         if ((sp->b.mode & FAXMODE_WORDALIGN) && | 
 |             !isAligned(tif->tif_rawcp, uint16_t)) | 
 |             Fax3FlushBits(tif, sp); | 
 |     } | 
 |     return (1); | 
 | } | 
 |  | 
 | static const tableentry horizcode = {3, 0x1, 0}; /* 001 */ | 
 | static const tableentry passcode = {4, 0x1, 0};  /* 0001 */ | 
 | static const tableentry vcodes[7] = { | 
 |     {7, 0x03, 0}, /* 0000 011 */ | 
 |     {6, 0x03, 0}, /* 0000 11 */ | 
 |     {3, 0x03, 0}, /* 011 */ | 
 |     {1, 0x1, 0},  /* 1 */ | 
 |     {3, 0x2, 0},  /* 010 */ | 
 |     {6, 0x02, 0}, /* 0000 10 */ | 
 |     {7, 0x02, 0}  /* 0000 010 */ | 
 | }; | 
 |  | 
 | /* | 
 |  * 2d-encode a row of pixels.  Consult the CCITT | 
 |  * documentation for the algorithm. | 
 |  */ | 
 | static int Fax3Encode2DRow(TIFF *tif, unsigned char *bp, unsigned char *rp, | 
 |                            uint32_t bits) | 
 | { | 
 | #define PIXEL(buf, ix) ((((buf)[(ix) >> 3]) >> (7 - ((ix)&7))) & 1) | 
 |     uint32_t a0 = 0; | 
 |     uint32_t a1 = (PIXEL(bp, 0) != 0 ? 0 : finddiff(bp, 0, bits, 0)); | 
 |     uint32_t b1 = (PIXEL(rp, 0) != 0 ? 0 : finddiff(rp, 0, bits, 0)); | 
 |     uint32_t a2, b2; | 
 |  | 
 |     for (;;) | 
 |     { | 
 |         b2 = finddiff2(rp, b1, bits, PIXEL(rp, b1)); | 
 |         if (b2 >= a1) | 
 |         { | 
 |             /* Naive computation triggers | 
 |              * -fsanitize=undefined,unsigned-integer-overflow */ | 
 |             /* although it is correct unless the difference between both is < 31 | 
 |              * bit */ | 
 |             /* int32_t d = b1 - a1; */ | 
 |             int32_t d = (b1 >= a1 && b1 - a1 <= 3U)  ? (int32_t)(b1 - a1) | 
 |                         : (b1 < a1 && a1 - b1 <= 3U) ? -(int32_t)(a1 - b1) | 
 |                                                      : 0x7FFFFFFF; | 
 |             if (!(-3 <= d && d <= 3)) | 
 |             { /* horizontal mode */ | 
 |                 a2 = finddiff2(bp, a1, bits, PIXEL(bp, a1)); | 
 |                 if (!putcode(tif, &horizcode)) | 
 |                     return 0; | 
 |                 if (a0 + a1 == 0 || PIXEL(bp, a0) == 0) | 
 |                 { | 
 |                     if (!putspan(tif, a1 - a0, TIFFFaxWhiteCodes)) | 
 |                         return 0; | 
 |                     if (!putspan(tif, a2 - a1, TIFFFaxBlackCodes)) | 
 |                         return 0; | 
 |                 } | 
 |                 else | 
 |                 { | 
 |                     if (!putspan(tif, a1 - a0, TIFFFaxBlackCodes)) | 
 |                         return 0; | 
 |                     if (!putspan(tif, a2 - a1, TIFFFaxWhiteCodes)) | 
 |                         return 0; | 
 |                 } | 
 |                 a0 = a2; | 
 |             } | 
 |             else | 
 |             { /* vertical mode */ | 
 |                 if (!putcode(tif, &vcodes[d + 3])) | 
 |                     return 0; | 
 |                 a0 = a1; | 
 |             } | 
 |         } | 
 |         else | 
 |         { /* pass mode */ | 
 |             if (!putcode(tif, &passcode)) | 
 |                 return 0; | 
 |             a0 = b2; | 
 |         } | 
 |         if (a0 >= bits) | 
 |             break; | 
 |         a1 = finddiff(bp, a0, bits, PIXEL(bp, a0)); | 
 |         b1 = finddiff(rp, a0, bits, !PIXEL(bp, a0)); | 
 |         b1 = finddiff(rp, b1, bits, PIXEL(bp, a0)); | 
 |     } | 
 |     return (1); | 
 | #undef PIXEL | 
 | } | 
 |  | 
 | /* | 
 |  * Encode a buffer of pixels. | 
 |  */ | 
 | static int Fax3Encode(TIFF *tif, uint8_t *bp, tmsize_t cc, uint16_t s) | 
 | { | 
 |     static const char module[] = "Fax3Encode"; | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     (void)s; | 
 |     if (cc % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be written"); | 
 |         return (0); | 
 |     } | 
 |     while (cc > 0) | 
 |     { | 
 |         if ((sp->b.mode & FAXMODE_NOEOL) == 0) | 
 |         { | 
 |             if (!Fax3PutEOL(tif)) | 
 |                 return 0; | 
 |         } | 
 |         if (is2DEncoding(sp)) | 
 |         { | 
 |             if (sp->tag == G3_1D) | 
 |             { | 
 |                 if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels)) | 
 |                     return (0); | 
 |                 sp->tag = G3_2D; | 
 |             } | 
 |             else | 
 |             { | 
 |                 if (!Fax3Encode2DRow(tif, bp, sp->refline, sp->b.rowpixels)) | 
 |                     return (0); | 
 |                 sp->k--; | 
 |             } | 
 |             if (sp->k == 0) | 
 |             { | 
 |                 sp->tag = G3_1D; | 
 |                 sp->k = sp->maxk - 1; | 
 |             } | 
 |             else | 
 |                 _TIFFmemcpy(sp->refline, bp, sp->b.rowbytes); | 
 |         } | 
 |         else | 
 |         { | 
 |             if (!Fax3Encode1DRow(tif, bp, sp->b.rowpixels)) | 
 |                 return (0); | 
 |         } | 
 |         bp += sp->b.rowbytes; | 
 |         cc -= sp->b.rowbytes; | 
 |     } | 
 |     return (1); | 
 | } | 
 |  | 
 | static int Fax3PostEncode(TIFF *tif) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |  | 
 |     if (sp->bit != 8) | 
 |         Fax3FlushBits(tif, sp); | 
 |     return (1); | 
 | } | 
 |  | 
 | static int _Fax3Close(TIFF *tif) | 
 | { | 
 |     if ((Fax3State(tif)->mode & FAXMODE_NORTC) == 0 && tif->tif_rawcp) | 
 |     { | 
 |         Fax3CodecState *sp = EncoderState(tif); | 
 |         unsigned int code = EOL; | 
 |         unsigned int length = 12; | 
 |         int i; | 
 |  | 
 |         if (is2DEncoding(sp)) | 
 |         { | 
 |             code = (code << 1) | (sp->tag == G3_1D); | 
 |             length++; | 
 |         } | 
 |         for (i = 0; i < 6; i++) | 
 |             Fax3PutBits(tif, code, length); | 
 |         Fax3FlushBits(tif, sp); | 
 |     } | 
 |     return 1; | 
 | } | 
 |  | 
 | static void Fax3Close(TIFF *tif) { _Fax3Close(tif); } | 
 |  | 
 | static void Fax3Cleanup(TIFF *tif) | 
 | { | 
 |     Fax3CodecState *sp = DecoderState(tif); | 
 |  | 
 |     assert(sp != 0); | 
 |  | 
 |     tif->tif_tagmethods.vgetfield = sp->b.vgetparent; | 
 |     tif->tif_tagmethods.vsetfield = sp->b.vsetparent; | 
 |     tif->tif_tagmethods.printdir = sp->b.printdir; | 
 |  | 
 |     if (sp->runs) | 
 |         _TIFFfreeExt(tif, sp->runs); | 
 |     if (sp->refline) | 
 |         _TIFFfreeExt(tif, sp->refline); | 
 |  | 
 |     _TIFFfreeExt(tif, tif->tif_data); | 
 |     tif->tif_data = NULL; | 
 |  | 
 |     _TIFFSetDefaultCompressionState(tif); | 
 | } | 
 |  | 
 | #define FIELD_BADFAXLINES (FIELD_CODEC + 0) | 
 | #define FIELD_CLEANFAXDATA (FIELD_CODEC + 1) | 
 | #define FIELD_BADFAXRUN (FIELD_CODEC + 2) | 
 |  | 
 | #define FIELD_OPTIONS (FIELD_CODEC + 7) | 
 |  | 
 | static const TIFFField faxFields[] = { | 
 |     {TIFFTAG_FAXMODE, 0, 0, TIFF_ANY, 0, TIFF_SETGET_INT, TIFF_SETGET_UNDEFINED, | 
 |      FIELD_PSEUDO, FALSE, FALSE, "FaxMode", NULL}, | 
 |     {TIFFTAG_FAXFILLFUNC, 0, 0, TIFF_ANY, 0, TIFF_SETGET_OTHER, | 
 |      TIFF_SETGET_UNDEFINED, FIELD_PSEUDO, FALSE, FALSE, "FaxFillFunc", NULL}, | 
 |     {TIFFTAG_BADFAXLINES, 1, 1, TIFF_LONG, 0, TIFF_SETGET_UINT32, | 
 |      TIFF_SETGET_UINT32, FIELD_BADFAXLINES, TRUE, FALSE, "BadFaxLines", NULL}, | 
 |     {TIFFTAG_CLEANFAXDATA, 1, 1, TIFF_SHORT, 0, TIFF_SETGET_UINT16, | 
 |      TIFF_SETGET_UINT16, FIELD_CLEANFAXDATA, TRUE, FALSE, "CleanFaxData", NULL}, | 
 |     {TIFFTAG_CONSECUTIVEBADFAXLINES, 1, 1, TIFF_LONG, 0, TIFF_SETGET_UINT32, | 
 |      TIFF_SETGET_UINT32, FIELD_BADFAXRUN, TRUE, FALSE, "ConsecutiveBadFaxLines", | 
 |      NULL}}; | 
 | static const TIFFField fax3Fields[] = { | 
 |     {TIFFTAG_GROUP3OPTIONS, 1, 1, TIFF_LONG, 0, TIFF_SETGET_UINT32, | 
 |      TIFF_SETGET_UINT32, FIELD_OPTIONS, FALSE, FALSE, "Group3Options", NULL}, | 
 | }; | 
 | static const TIFFField fax4Fields[] = { | 
 |     {TIFFTAG_GROUP4OPTIONS, 1, 1, TIFF_LONG, 0, TIFF_SETGET_UINT32, | 
 |      TIFF_SETGET_UINT32, FIELD_OPTIONS, FALSE, FALSE, "Group4Options", NULL}, | 
 | }; | 
 |  | 
 | static int Fax3VSetField(TIFF *tif, uint32_t tag, va_list ap) | 
 | { | 
 |     Fax3BaseState *sp = Fax3State(tif); | 
 |     const TIFFField *fip; | 
 |  | 
 |     assert(sp != 0); | 
 |     assert(sp->vsetparent != 0); | 
 |  | 
 |     switch (tag) | 
 |     { | 
 |         case TIFFTAG_FAXMODE: | 
 |             sp->mode = (int)va_arg(ap, int); | 
 |             return 1; /* NB: pseudo tag */ | 
 |         case TIFFTAG_FAXFILLFUNC: | 
 |             DecoderState(tif)->fill = va_arg(ap, TIFFFaxFillFunc); | 
 |             return 1; /* NB: pseudo tag */ | 
 |         case TIFFTAG_GROUP3OPTIONS: | 
 |             /* XXX: avoid reading options if compression mismatches. */ | 
 |             if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX3) | 
 |                 sp->groupoptions = (uint32_t)va_arg(ap, uint32_t); | 
 |             break; | 
 |         case TIFFTAG_GROUP4OPTIONS: | 
 |             /* XXX: avoid reading options if compression mismatches. */ | 
 |             if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4) | 
 |                 sp->groupoptions = (uint32_t)va_arg(ap, uint32_t); | 
 |             break; | 
 |         case TIFFTAG_BADFAXLINES: | 
 |             sp->badfaxlines = (uint32_t)va_arg(ap, uint32_t); | 
 |             break; | 
 |         case TIFFTAG_CLEANFAXDATA: | 
 |             sp->cleanfaxdata = (uint16_t)va_arg(ap, uint16_vap); | 
 |             break; | 
 |         case TIFFTAG_CONSECUTIVEBADFAXLINES: | 
 |             sp->badfaxrun = (uint32_t)va_arg(ap, uint32_t); | 
 |             break; | 
 |         default: | 
 |             return (*sp->vsetparent)(tif, tag, ap); | 
 |     } | 
 |  | 
 |     if ((fip = TIFFFieldWithTag(tif, tag)) != NULL) | 
 |         TIFFSetFieldBit(tif, fip->field_bit); | 
 |     else | 
 |         return 0; | 
 |  | 
 |     tif->tif_flags |= TIFF_DIRTYDIRECT; | 
 |     return 1; | 
 | } | 
 |  | 
 | static int Fax3VGetField(TIFF *tif, uint32_t tag, va_list ap) | 
 | { | 
 |     Fax3BaseState *sp = Fax3State(tif); | 
 |  | 
 |     assert(sp != 0); | 
 |  | 
 |     switch (tag) | 
 |     { | 
 |         case TIFFTAG_FAXMODE: | 
 |             *va_arg(ap, int *) = sp->mode; | 
 |             break; | 
 |         case TIFFTAG_FAXFILLFUNC: | 
 |             *va_arg(ap, TIFFFaxFillFunc *) = DecoderState(tif)->fill; | 
 |             break; | 
 |         case TIFFTAG_GROUP3OPTIONS: | 
 |         case TIFFTAG_GROUP4OPTIONS: | 
 |             *va_arg(ap, uint32_t *) = sp->groupoptions; | 
 |             break; | 
 |         case TIFFTAG_BADFAXLINES: | 
 |             *va_arg(ap, uint32_t *) = sp->badfaxlines; | 
 |             break; | 
 |         case TIFFTAG_CLEANFAXDATA: | 
 |             *va_arg(ap, uint16_t *) = sp->cleanfaxdata; | 
 |             break; | 
 |         case TIFFTAG_CONSECUTIVEBADFAXLINES: | 
 |             *va_arg(ap, uint32_t *) = sp->badfaxrun; | 
 |             break; | 
 |         default: | 
 |             return (*sp->vgetparent)(tif, tag, ap); | 
 |     } | 
 |     return (1); | 
 | } | 
 |  | 
 | static void Fax3PrintDir(TIFF *tif, FILE *fd, long flags) | 
 | { | 
 |     Fax3BaseState *sp = Fax3State(tif); | 
 |  | 
 |     assert(sp != 0); | 
 |  | 
 |     (void)flags; | 
 |     if (TIFFFieldSet(tif, FIELD_OPTIONS)) | 
 |     { | 
 |         const char *sep = " "; | 
 |         if (tif->tif_dir.td_compression == COMPRESSION_CCITTFAX4) | 
 |         { | 
 |             fprintf(fd, "  Group 4 Options:"); | 
 |             if (sp->groupoptions & GROUP4OPT_UNCOMPRESSED) | 
 |                 fprintf(fd, "%suncompressed data", sep); | 
 |         } | 
 |         else | 
 |         { | 
 |  | 
 |             fprintf(fd, "  Group 3 Options:"); | 
 |             if (sp->groupoptions & GROUP3OPT_2DENCODING) | 
 |             { | 
 |                 fprintf(fd, "%s2-d encoding", sep); | 
 |                 sep = "+"; | 
 |             } | 
 |             if (sp->groupoptions & GROUP3OPT_FILLBITS) | 
 |             { | 
 |                 fprintf(fd, "%sEOL padding", sep); | 
 |                 sep = "+"; | 
 |             } | 
 |             if (sp->groupoptions & GROUP3OPT_UNCOMPRESSED) | 
 |                 fprintf(fd, "%suncompressed data", sep); | 
 |         } | 
 |         fprintf(fd, " (%" PRIu32 " = 0x%" PRIx32 ")\n", sp->groupoptions, | 
 |                 sp->groupoptions); | 
 |     } | 
 |     if (TIFFFieldSet(tif, FIELD_CLEANFAXDATA)) | 
 |     { | 
 |         fprintf(fd, "  Fax Data:"); | 
 |         switch (sp->cleanfaxdata) | 
 |         { | 
 |             case CLEANFAXDATA_CLEAN: | 
 |                 fprintf(fd, " clean"); | 
 |                 break; | 
 |             case CLEANFAXDATA_REGENERATED: | 
 |                 fprintf(fd, " receiver regenerated"); | 
 |                 break; | 
 |             case CLEANFAXDATA_UNCLEAN: | 
 |                 fprintf(fd, " uncorrected errors"); | 
 |                 break; | 
 |         } | 
 |         fprintf(fd, " (%" PRIu16 " = 0x%" PRIx16 ")\n", sp->cleanfaxdata, | 
 |                 sp->cleanfaxdata); | 
 |     } | 
 |     if (TIFFFieldSet(tif, FIELD_BADFAXLINES)) | 
 |         fprintf(fd, "  Bad Fax Lines: %" PRIu32 "\n", sp->badfaxlines); | 
 |     if (TIFFFieldSet(tif, FIELD_BADFAXRUN)) | 
 |         fprintf(fd, "  Consecutive Bad Fax Lines: %" PRIu32 "\n", | 
 |                 sp->badfaxrun); | 
 |     if (sp->printdir) | 
 |         (*sp->printdir)(tif, fd, flags); | 
 | } | 
 |  | 
 | static int InitCCITTFax3(TIFF *tif) | 
 | { | 
 |     static const char module[] = "InitCCITTFax3"; | 
 |     Fax3BaseState *sp; | 
 |  | 
 |     /* | 
 |      * Merge codec-specific tag information. | 
 |      */ | 
 |     if (!_TIFFMergeFields(tif, faxFields, TIFFArrayCount(faxFields))) | 
 |     { | 
 |         TIFFErrorExtR(tif, "InitCCITTFax3", | 
 |                       "Merging common CCITT Fax codec-specific tags failed"); | 
 |         return 0; | 
 |     } | 
 |  | 
 |     /* | 
 |      * Allocate state block so tag methods have storage to record values. | 
 |      */ | 
 |     tif->tif_data = (uint8_t *)_TIFFmallocExt(tif, sizeof(Fax3CodecState)); | 
 |  | 
 |     if (tif->tif_data == NULL) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "No space for state block"); | 
 |         return (0); | 
 |     } | 
 |     _TIFFmemset(tif->tif_data, 0, sizeof(Fax3CodecState)); | 
 |  | 
 |     sp = Fax3State(tif); | 
 |     sp->rw_mode = tif->tif_mode; | 
 |  | 
 |     /* | 
 |      * Override parent get/set field methods. | 
 |      */ | 
 |     sp->vgetparent = tif->tif_tagmethods.vgetfield; | 
 |     tif->tif_tagmethods.vgetfield = Fax3VGetField; /* hook for codec tags */ | 
 |     sp->vsetparent = tif->tif_tagmethods.vsetfield; | 
 |     tif->tif_tagmethods.vsetfield = Fax3VSetField; /* hook for codec tags */ | 
 |     sp->printdir = tif->tif_tagmethods.printdir; | 
 |     tif->tif_tagmethods.printdir = Fax3PrintDir; /* hook for codec tags */ | 
 |     sp->groupoptions = 0; | 
 |  | 
 |     if (sp->rw_mode == O_RDONLY) /* FIXME: improve for in place update */ | 
 |         tif->tif_flags |= TIFF_NOBITREV; /* decoder does bit reversal */ | 
 |     DecoderState(tif)->runs = NULL; | 
 |     TIFFSetField(tif, TIFFTAG_FAXFILLFUNC, _TIFFFax3fillruns); | 
 |     EncoderState(tif)->refline = NULL; | 
 |  | 
 |     /* | 
 |      * Install codec methods. | 
 |      */ | 
 |     tif->tif_fixuptags = Fax3FixupTags; | 
 |     tif->tif_setupdecode = Fax3SetupState; | 
 |     tif->tif_predecode = Fax3PreDecode; | 
 |     tif->tif_decoderow = Fax3Decode1D; | 
 |     tif->tif_decodestrip = Fax3Decode1D; | 
 |     tif->tif_decodetile = Fax3Decode1D; | 
 |     tif->tif_setupencode = Fax3SetupState; | 
 |     tif->tif_preencode = Fax3PreEncode; | 
 |     tif->tif_postencode = Fax3PostEncode; | 
 |     tif->tif_encoderow = Fax3Encode; | 
 |     tif->tif_encodestrip = Fax3Encode; | 
 |     tif->tif_encodetile = Fax3Encode; | 
 |     tif->tif_close = Fax3Close; | 
 |     tif->tif_cleanup = Fax3Cleanup; | 
 |  | 
 |     return (1); | 
 | } | 
 |  | 
 | int TIFFInitCCITTFax3(TIFF *tif, int scheme) | 
 | { | 
 |     (void)scheme; | 
 |     if (InitCCITTFax3(tif)) | 
 |     { | 
 |         /* | 
 |          * Merge codec-specific tag information. | 
 |          */ | 
 |         if (!_TIFFMergeFields(tif, fax3Fields, TIFFArrayCount(fax3Fields))) | 
 |         { | 
 |             TIFFErrorExtR(tif, "TIFFInitCCITTFax3", | 
 |                           "Merging CCITT Fax 3 codec-specific tags failed"); | 
 |             return 0; | 
 |         } | 
 |  | 
 |         /* | 
 |          * The default format is Class/F-style w/o RTC. | 
 |          */ | 
 |         return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_CLASSF); | 
 |     } | 
 |     else | 
 |         return 01; | 
 | } | 
 |  | 
 | /* | 
 |  * CCITT Group 4 (T.6) Facsimile-compatible | 
 |  * Compression Scheme Support. | 
 |  */ | 
 |  | 
 | #define SWAP(t, a, b)                                                          \ | 
 |     {                                                                          \ | 
 |         t x;                                                                   \ | 
 |         x = (a);                                                               \ | 
 |         (a) = (b);                                                             \ | 
 |         (b) = x;                                                               \ | 
 |     } | 
 | /* | 
 |  * Decode the requested amount of G4-encoded data. | 
 |  */ | 
 | static int Fax4Decode(TIFF *tif, uint8_t *buf, tmsize_t occ, uint16_t s) | 
 | { | 
 |     DECLARE_STATE_2D(tif, sp, "Fax4Decode"); | 
 |     (void)s; | 
 |     if (occ % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be read"); | 
 |         return (-1); | 
 |     } | 
 |     if (sp->eofReachedCount >= EOF_REACHED_COUNT_THRESHOLD) | 
 |     { | 
 |         TIFFErrorExtR( | 
 |             tif, module, | 
 |             "End of file has already been reached %d times within that strip", | 
 |             sp->eofReachedCount); | 
 |         return (-1); | 
 |     } | 
 |     CACHE_STATE(tif, sp); | 
 |     int start = sp->line; | 
 |     while (occ > 0) | 
 |     { | 
 |         a0 = 0; | 
 |         RunLength = 0; | 
 |         pa = thisrun = sp->curruns; | 
 |         pb = sp->refruns; | 
 |         b1 = *pb++; | 
 | #ifdef FAX3_DEBUG | 
 |         printf("\nBitAcc=%08" PRIX32 ", BitsAvail = %d\n", BitAcc, BitsAvail); | 
 |         printf("-------------------- %d\n", tif->tif_row); | 
 |         fflush(stdout); | 
 | #endif | 
 |         EXPAND2D(EOFG4); | 
 |         if (EOLcnt) | 
 |             goto EOFG4; | 
 |         if (((lastx + 7) >> 3) > (int)occ) /* check for buffer overrun */ | 
 |         { | 
 |             TIFFErrorExtR(tif, module, | 
 |                           "Buffer overrun detected : %" TIFF_SSIZE_FORMAT | 
 |                           " bytes available, %d bits needed", | 
 |                           occ, lastx); | 
 |             return -1; | 
 |         } | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         SETVALUE(0); /* imaginary change for reference */ | 
 |         SWAP(uint32_t *, sp->curruns, sp->refruns); | 
 |         buf += sp->b.rowbytes; | 
 |         occ -= sp->b.rowbytes; | 
 |         sp->line++; | 
 |         continue; | 
 |     EOFG4: | 
 |         NeedBits16(13, BADG4); | 
 |     BADG4: | 
 | #ifdef FAX3_DEBUG | 
 |         if (GetBits(13) != 0x1001) | 
 |             fputs("Bad EOFB\n", stderr); | 
 | #endif | 
 |         ClrBits(13); | 
 |         if (((lastx + 7) >> 3) > (int)occ) /* check for buffer overrun */ | 
 |         { | 
 |             TIFFErrorExtR(tif, module, | 
 |                           "Buffer overrun detected : %" TIFF_SSIZE_FORMAT | 
 |                           " bytes available, %d bits needed", | 
 |                           occ, lastx); | 
 |             return -1; | 
 |         } | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         UNCACHE_STATE(tif, sp); | 
 |         return (sp->line != start | 
 |                     ? 1 | 
 |                     : -1); /* don't error on badly-terminated strips */ | 
 |     } | 
 |     UNCACHE_STATE(tif, sp); | 
 |     return (1); | 
 | } | 
 | #undef SWAP | 
 |  | 
 | /* | 
 |  * Encode the requested amount of data. | 
 |  */ | 
 | static int Fax4Encode(TIFF *tif, uint8_t *bp, tmsize_t cc, uint16_t s) | 
 | { | 
 |     static const char module[] = "Fax4Encode"; | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |     (void)s; | 
 |     if (cc % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be written"); | 
 |         return (0); | 
 |     } | 
 |     while (cc > 0) | 
 |     { | 
 |         if (!Fax3Encode2DRow(tif, bp, sp->refline, sp->b.rowpixels)) | 
 |             return (0); | 
 |         _TIFFmemcpy(sp->refline, bp, sp->b.rowbytes); | 
 |         bp += sp->b.rowbytes; | 
 |         cc -= sp->b.rowbytes; | 
 |     } | 
 |     return (1); | 
 | } | 
 |  | 
 | static int Fax4PostEncode(TIFF *tif) | 
 | { | 
 |     Fax3CodecState *sp = EncoderState(tif); | 
 |  | 
 |     /* terminate strip w/ EOFB */ | 
 |     Fax3PutBits(tif, EOL, 12); | 
 |     Fax3PutBits(tif, EOL, 12); | 
 |     if (sp->bit != 8) | 
 |         Fax3FlushBits(tif, sp); | 
 |     return (1); | 
 | } | 
 |  | 
 | int TIFFInitCCITTFax4(TIFF *tif, int scheme) | 
 | { | 
 |     (void)scheme; | 
 |     if (InitCCITTFax3(tif)) | 
 |     { /* reuse G3 support */ | 
 |         /* | 
 |          * Merge codec-specific tag information. | 
 |          */ | 
 |         if (!_TIFFMergeFields(tif, fax4Fields, TIFFArrayCount(fax4Fields))) | 
 |         { | 
 |             TIFFErrorExtR(tif, "TIFFInitCCITTFax4", | 
 |                           "Merging CCITT Fax 4 codec-specific tags failed"); | 
 |             return 0; | 
 |         } | 
 |  | 
 |         tif->tif_decoderow = Fax4Decode; | 
 |         tif->tif_decodestrip = Fax4Decode; | 
 |         tif->tif_decodetile = Fax4Decode; | 
 |         tif->tif_encoderow = Fax4Encode; | 
 |         tif->tif_encodestrip = Fax4Encode; | 
 |         tif->tif_encodetile = Fax4Encode; | 
 |         tif->tif_postencode = Fax4PostEncode; | 
 |         /* | 
 |          * Suppress RTC at the end of each strip. | 
 |          */ | 
 |         return TIFFSetField(tif, TIFFTAG_FAXMODE, FAXMODE_NORTC); | 
 |     } | 
 |     else | 
 |         return (0); | 
 | } | 
 |  | 
 | /* | 
 |  * CCITT Group 3 1-D Modified Huffman RLE Compression Support. | 
 |  * (Compression algorithms 2 and 32771) | 
 |  */ | 
 |  | 
 | /* | 
 |  * Decode the requested amount of RLE-encoded data. | 
 |  */ | 
 | static int Fax3DecodeRLE(TIFF *tif, uint8_t *buf, tmsize_t occ, uint16_t s) | 
 | { | 
 |     DECLARE_STATE(tif, sp, "Fax3DecodeRLE"); | 
 |     int mode = sp->b.mode; | 
 |     (void)s; | 
 |     if (occ % sp->b.rowbytes) | 
 |     { | 
 |         TIFFErrorExtR(tif, module, "Fractional scanlines cannot be read"); | 
 |         return (-1); | 
 |     } | 
 |     CACHE_STATE(tif, sp); | 
 |     thisrun = sp->curruns; | 
 |     while (occ > 0) | 
 |     { | 
 |         a0 = 0; | 
 |         RunLength = 0; | 
 |         pa = thisrun; | 
 | #ifdef FAX3_DEBUG | 
 |         printf("\nBitAcc=%08" PRIX32 ", BitsAvail = %d\n", BitAcc, BitsAvail); | 
 |         printf("-------------------- %" PRIu32 "\n", tif->tif_row); | 
 |         fflush(stdout); | 
 | #endif | 
 |         EXPAND1D(EOFRLE); | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         /* | 
 |          * Cleanup at the end of the row. | 
 |          */ | 
 |         if (mode & FAXMODE_BYTEALIGN) | 
 |         { | 
 |             int n = BitsAvail - (BitsAvail & ~7); | 
 |             ClrBits(n); | 
 |         } | 
 |         else if (mode & FAXMODE_WORDALIGN) | 
 |         { | 
 |             int n = BitsAvail - (BitsAvail & ~15); | 
 |             ClrBits(n); | 
 |             if (BitsAvail == 0 && !isAligned(cp, uint16_t)) | 
 |                 cp++; | 
 |         } | 
 |         buf += sp->b.rowbytes; | 
 |         occ -= sp->b.rowbytes; | 
 |         sp->line++; | 
 |         continue; | 
 |     EOFRLE: /* premature EOF */ | 
 |         (*sp->fill)(buf, thisrun, pa, lastx); | 
 |         UNCACHE_STATE(tif, sp); | 
 |         return (-1); | 
 |     } | 
 |     UNCACHE_STATE(tif, sp); | 
 |     return (1); | 
 | } | 
 |  | 
 | int TIFFInitCCITTRLE(TIFF *tif, int scheme) | 
 | { | 
 |     (void)scheme; | 
 |     if (InitCCITTFax3(tif)) | 
 |     { /* reuse G3 support */ | 
 |         tif->tif_decoderow = Fax3DecodeRLE; | 
 |         tif->tif_decodestrip = Fax3DecodeRLE; | 
 |         tif->tif_decodetile = Fax3DecodeRLE; | 
 |         /* | 
 |          * Suppress RTC+EOLs when encoding and byte-align data. | 
 |          */ | 
 |         return TIFFSetField(tif, TIFFTAG_FAXMODE, | 
 |                             FAXMODE_NORTC | FAXMODE_NOEOL | FAXMODE_BYTEALIGN); | 
 |     } | 
 |     else | 
 |         return (0); | 
 | } | 
 |  | 
 | int TIFFInitCCITTRLEW(TIFF *tif, int scheme) | 
 | { | 
 |     (void)scheme; | 
 |     if (InitCCITTFax3(tif)) | 
 |     { /* reuse G3 support */ | 
 |         tif->tif_decoderow = Fax3DecodeRLE; | 
 |         tif->tif_decodestrip = Fax3DecodeRLE; | 
 |         tif->tif_decodetile = Fax3DecodeRLE; | 
 |         /* | 
 |          * Suppress RTC+EOLs when encoding and word-align data. | 
 |          */ | 
 |         return TIFFSetField(tif, TIFFTAG_FAXMODE, | 
 |                             FAXMODE_NORTC | FAXMODE_NOEOL | FAXMODE_WORDALIGN); | 
 |     } | 
 |     else | 
 |         return (0); | 
 | } | 
 | #endif /* CCITT_SUPPORT */ |