| /* |
| * The copyright in this software is being made available under the 2-clauses |
| * BSD License, included below. This software may be subject to other third |
| * party and contributor rights, including patent rights, and no such rights |
| * are granted under this license. |
| * |
| * Copyright (c) 2002-2014, Universite catholique de Louvain (UCL), Belgium |
| * Copyright (c) 2002-2014, Professor Benoit Macq |
| * Copyright (c) 2001-2003, David Janssens |
| * Copyright (c) 2002-2003, Yannick Verschueren |
| * Copyright (c) 2003-2007, Francois-Olivier Devaux |
| * Copyright (c) 2003-2014, Antonin Descampe |
| * Copyright (c) 2005, Herve Drolon, FreeImage Team |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS `AS IS' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE |
| * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE |
| * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE |
| * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| * POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "opj_includes.h" |
| |
| /** @defgroup BIO BIO - Individual bit input-output stream */ |
| /*@{*/ |
| |
| /** @name Local static functions */ |
| /*@{*/ |
| |
| /** |
| Read a bit |
| @param bio BIO handle |
| @return Returns the read bit |
| */ |
| static OPJ_UINT32 opj_bio_getbit(opj_bio_t *bio); |
| /** |
| Write a byte |
| @param bio BIO handle |
| @return Returns OPJ_TRUE if successful, returns OPJ_FALSE otherwise |
| */ |
| static OPJ_BOOL opj_bio_byteout(opj_bio_t *bio); |
| /** |
| Read a byte |
| @param bio BIO handle |
| @return Returns OPJ_TRUE if successful, returns OPJ_FALSE otherwise |
| */ |
| static OPJ_BOOL opj_bio_bytein(opj_bio_t *bio); |
| |
| /*@}*/ |
| |
| /*@}*/ |
| |
| /* |
| ========================================================== |
| local functions |
| ========================================================== |
| */ |
| |
| static OPJ_BOOL opj_bio_byteout(opj_bio_t *bio) |
| { |
| bio->buf = (bio->buf << 8) & 0xffff; |
| bio->ct = bio->buf == 0xff00 ? 7 : 8; |
| if ((OPJ_SIZE_T)bio->bp >= (OPJ_SIZE_T)bio->end) { |
| return OPJ_FALSE; |
| } |
| *bio->bp++ = (OPJ_BYTE)(bio->buf >> 8); |
| return OPJ_TRUE; |
| } |
| |
| static OPJ_BOOL opj_bio_bytein(opj_bio_t *bio) |
| { |
| bio->buf = (bio->buf << 8) & 0xffff; |
| bio->ct = bio->buf == 0xff00 ? 7 : 8; |
| if ((OPJ_SIZE_T)bio->bp >= (OPJ_SIZE_T)bio->end) { |
| return OPJ_FALSE; |
| } |
| bio->buf |= *bio->bp++; |
| return OPJ_TRUE; |
| } |
| |
| static OPJ_UINT32 opj_bio_getbit(opj_bio_t *bio) |
| { |
| if (bio->ct == 0) { |
| opj_bio_bytein( |
| bio); /* MSD: why not check the return value of this function ? */ |
| } |
| bio->ct--; |
| return (bio->buf >> bio->ct) & 1; |
| } |
| |
| /* |
| ========================================================== |
| Bit Input/Output interface |
| ========================================================== |
| */ |
| |
| opj_bio_t* opj_bio_create(void) |
| { |
| opj_bio_t *bio = (opj_bio_t*)opj_malloc(sizeof(opj_bio_t)); |
| return bio; |
| } |
| |
| void opj_bio_destroy(opj_bio_t *bio) |
| { |
| if (bio) { |
| opj_free(bio); |
| } |
| } |
| |
| ptrdiff_t opj_bio_numbytes(opj_bio_t *bio) |
| { |
| return (bio->bp - bio->start); |
| } |
| |
| void opj_bio_init_enc(opj_bio_t *bio, OPJ_BYTE *bp, OPJ_UINT32 len) |
| { |
| bio->start = bp; |
| bio->end = bp + len; |
| bio->bp = bp; |
| bio->buf = 0; |
| bio->ct = 8; |
| } |
| |
| void opj_bio_init_dec(opj_bio_t *bio, OPJ_BYTE *bp, OPJ_UINT32 len) |
| { |
| bio->start = bp; |
| bio->end = bp + len; |
| bio->bp = bp; |
| bio->buf = 0; |
| bio->ct = 0; |
| } |
| |
| void opj_bio_putbit(opj_bio_t *bio, OPJ_UINT32 b) |
| { |
| if (bio->ct == 0) { |
| opj_bio_byteout( |
| bio); /* MSD: why not check the return value of this function ? */ |
| } |
| bio->ct--; |
| bio->buf |= b << bio->ct; |
| } |
| |
| void opj_bio_write(opj_bio_t *bio, OPJ_UINT32 v, OPJ_UINT32 n) |
| { |
| OPJ_INT32 i; |
| |
| assert((n > 0U) && (n <= 32U)); |
| for (i = (OPJ_INT32)n - 1; i >= 0; i--) { |
| opj_bio_putbit(bio, (v >> i) & 1); |
| } |
| } |
| |
| OPJ_UINT32 opj_bio_read(opj_bio_t *bio, OPJ_UINT32 n) |
| { |
| OPJ_INT32 i; |
| OPJ_UINT32 v; |
| |
| assert((n > 0U) /* && (n <= 32U)*/); |
| #ifdef OPJ_UBSAN_BUILD |
| /* This assert fails for some corrupted images which are gracefully rejected */ |
| /* Add this assert only for ubsan build. */ |
| /* This is the condition for overflow not to occur below which is needed because of OPJ_NOSANITIZE */ |
| assert(n <= 32U); |
| #endif |
| v = 0U; |
| for (i = (OPJ_INT32)n - 1; i >= 0; i--) { |
| v |= opj_bio_getbit(bio) << |
| i; /* can't overflow, opj_bio_getbit returns 0 or 1 */ |
| } |
| return v; |
| } |
| |
| OPJ_BOOL opj_bio_flush(opj_bio_t *bio) |
| { |
| if (! opj_bio_byteout(bio)) { |
| return OPJ_FALSE; |
| } |
| if (bio->ct == 7) { |
| if (! opj_bio_byteout(bio)) { |
| return OPJ_FALSE; |
| } |
| } |
| return OPJ_TRUE; |
| } |
| |
| OPJ_BOOL opj_bio_inalign(opj_bio_t *bio) |
| { |
| if ((bio->buf & 0xff) == 0xff) { |
| if (! opj_bio_bytein(bio)) { |
| return OPJ_FALSE; |
| } |
| } |
| bio->ct = 0; |
| return OPJ_TRUE; |
| } |