diff options
Diffstat (limited to 'plugins/AdvaImg/src/LibJPEG/jdmarker.c')
| -rw-r--r-- | plugins/AdvaImg/src/LibJPEG/jdmarker.c | 2911 |
1 files changed, 1505 insertions, 1406 deletions
diff --git a/plugins/AdvaImg/src/LibJPEG/jdmarker.c b/plugins/AdvaImg/src/LibJPEG/jdmarker.c index f2a9cc4295..47ebee9576 100644 --- a/plugins/AdvaImg/src/LibJPEG/jdmarker.c +++ b/plugins/AdvaImg/src/LibJPEG/jdmarker.c @@ -1,1406 +1,1505 @@ -/* - * jdmarker.c - * - * Copyright (C) 1991-1998, Thomas G. Lane. - * Modified 2009 by Guido Vollbeding. - * This file is part of the Independent JPEG Group's software. - * For conditions of distribution and use, see the accompanying README file. - * - * This file contains routines to decode JPEG datastream markers. - * Most of the complexity arises from our desire to support input - * suspension: if not all of the data for a marker is available, - * we must exit back to the application. On resumption, we reprocess - * the marker. - */ - -#define JPEG_INTERNALS -#include "jinclude.h" -#include "jpeglib.h" - - -typedef enum { /* JPEG marker codes */ - M_SOF0 = 0xc0, - M_SOF1 = 0xc1, - M_SOF2 = 0xc2, - M_SOF3 = 0xc3, - - M_SOF5 = 0xc5, - M_SOF6 = 0xc6, - M_SOF7 = 0xc7, - - M_JPG = 0xc8, - M_SOF9 = 0xc9, - M_SOF10 = 0xca, - M_SOF11 = 0xcb, - - M_SOF13 = 0xcd, - M_SOF14 = 0xce, - M_SOF15 = 0xcf, - - M_DHT = 0xc4, - - M_DAC = 0xcc, - - M_RST0 = 0xd0, - M_RST1 = 0xd1, - M_RST2 = 0xd2, - M_RST3 = 0xd3, - M_RST4 = 0xd4, - M_RST5 = 0xd5, - M_RST6 = 0xd6, - M_RST7 = 0xd7, - - M_SOI = 0xd8, - M_EOI = 0xd9, - M_SOS = 0xda, - M_DQT = 0xdb, - M_DNL = 0xdc, - M_DRI = 0xdd, - M_DHP = 0xde, - M_EXP = 0xdf, - - M_APP0 = 0xe0, - M_APP1 = 0xe1, - M_APP2 = 0xe2, - M_APP3 = 0xe3, - M_APP4 = 0xe4, - M_APP5 = 0xe5, - M_APP6 = 0xe6, - M_APP7 = 0xe7, - M_APP8 = 0xe8, - M_APP9 = 0xe9, - M_APP10 = 0xea, - M_APP11 = 0xeb, - M_APP12 = 0xec, - M_APP13 = 0xed, - M_APP14 = 0xee, - M_APP15 = 0xef, - - M_JPG0 = 0xf0, - M_JPG13 = 0xfd, - M_COM = 0xfe, - - M_TEM = 0x01, - - M_ERROR = 0x100 -} JPEG_MARKER; - - -/* Private state */ - -typedef struct { - struct jpeg_marker_reader pub; /* public fields */ - - /* Application-overridable marker processing methods */ - jpeg_marker_parser_method process_COM; - jpeg_marker_parser_method process_APPn[16]; - - /* Limit on marker data length to save for each marker type */ - unsigned int length_limit_COM; - unsigned int length_limit_APPn[16]; - - /* Status of COM/APPn marker saving */ - jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */ - unsigned int bytes_read; /* data bytes read so far in marker */ - /* Note: cur_marker is not linked into marker_list until it's all read. */ -} my_marker_reader; - -typedef my_marker_reader * my_marker_ptr; - - -/* - * Macros for fetching data from the data source module. - * - * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect - * the current restart point; we update them only when we have reached a - * suitable place to restart if a suspension occurs. - */ - -/* Declare and initialize local copies of input pointer/count */ -#define INPUT_VARS(cinfo) \ - struct jpeg_source_mgr * datasrc = (cinfo)->src; \ - const JOCTET * next_input_byte = datasrc->next_input_byte; \ - size_t bytes_in_buffer = datasrc->bytes_in_buffer - -/* Unload the local copies --- do this only at a restart boundary */ -#define INPUT_SYNC(cinfo) \ - ( datasrc->next_input_byte = next_input_byte, \ - datasrc->bytes_in_buffer = bytes_in_buffer ) - -/* Reload the local copies --- used only in MAKE_BYTE_AVAIL */ -#define INPUT_RELOAD(cinfo) \ - ( next_input_byte = datasrc->next_input_byte, \ - bytes_in_buffer = datasrc->bytes_in_buffer ) - -/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available. - * Note we do *not* do INPUT_SYNC before calling fill_input_buffer, - * but we must reload the local copies after a successful fill. - */ -#define MAKE_BYTE_AVAIL(cinfo,action) \ - if (bytes_in_buffer == 0) { \ - if (! (*datasrc->fill_input_buffer) (cinfo)) \ - { action; } \ - INPUT_RELOAD(cinfo); \ - } - -/* Read a byte into variable V. - * If must suspend, take the specified action (typically "return FALSE"). - */ -#define INPUT_BYTE(cinfo,V,action) \ - MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ - bytes_in_buffer--; \ - V = GETJOCTET(*next_input_byte++); ) - -/* As above, but read two bytes interpreted as an unsigned 16-bit integer. - * V should be declared unsigned int or perhaps INT32. - */ -#define INPUT_2BYTES(cinfo,V,action) \ - MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \ - bytes_in_buffer--; \ - V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \ - MAKE_BYTE_AVAIL(cinfo,action); \ - bytes_in_buffer--; \ - V += GETJOCTET(*next_input_byte++); ) - - -/* - * Routines to process JPEG markers. - * - * Entry condition: JPEG marker itself has been read and its code saved - * in cinfo->unread_marker; input restart point is just after the marker. - * - * Exit: if return TRUE, have read and processed any parameters, and have - * updated the restart point to point after the parameters. - * If return FALSE, was forced to suspend before reaching end of - * marker parameters; restart point has not been moved. Same routine - * will be called again after application supplies more input data. - * - * This approach to suspension assumes that all of a marker's parameters - * can fit into a single input bufferload. This should hold for "normal" - * markers. Some COM/APPn markers might have large parameter segments - * that might not fit. If we are simply dropping such a marker, we use - * skip_input_data to get past it, and thereby put the problem on the - * source manager's shoulders. If we are saving the marker's contents - * into memory, we use a slightly different convention: when forced to - * suspend, the marker processor updates the restart point to the end of - * what it's consumed (ie, the end of the buffer) before returning FALSE. - * On resumption, cinfo->unread_marker still contains the marker code, - * but the data source will point to the next chunk of marker data. - * The marker processor must retain internal state to deal with this. - * - * Note that we don't bother to avoid duplicate trace messages if a - * suspension occurs within marker parameters. Other side effects - * require more care. - */ - - -LOCAL(boolean) -get_soi (j_decompress_ptr cinfo) -/* Process an SOI marker */ -{ - int i; - - TRACEMS(cinfo, 1, JTRC_SOI); - - if (cinfo->marker->saw_SOI) - ERREXIT(cinfo, JERR_SOI_DUPLICATE); - - /* Reset all parameters that are defined to be reset by SOI */ - - for (i = 0; i < NUM_ARITH_TBLS; i++) { - cinfo->arith_dc_L[i] = 0; - cinfo->arith_dc_U[i] = 1; - cinfo->arith_ac_K[i] = 5; - } - cinfo->restart_interval = 0; - - /* Set initial assumptions for colorspace etc */ - - cinfo->jpeg_color_space = JCS_UNKNOWN; - cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */ - - cinfo->saw_JFIF_marker = FALSE; - cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */ - cinfo->JFIF_minor_version = 1; - cinfo->density_unit = 0; - cinfo->X_density = 1; - cinfo->Y_density = 1; - cinfo->saw_Adobe_marker = FALSE; - cinfo->Adobe_transform = 0; - - cinfo->marker->saw_SOI = TRUE; - - return TRUE; -} - - -LOCAL(boolean) -get_sof (j_decompress_ptr cinfo, boolean is_baseline, boolean is_prog, - boolean is_arith) -/* Process a SOFn marker */ -{ - INT32 length; - int c, ci; - jpeg_component_info * compptr; - INPUT_VARS(cinfo); - - cinfo->is_baseline = is_baseline; - cinfo->progressive_mode = is_prog; - cinfo->arith_code = is_arith; - - INPUT_2BYTES(cinfo, length, return FALSE); - - INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE); - INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE); - INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE); - INPUT_BYTE(cinfo, cinfo->num_components, return FALSE); - - length -= 8; - - TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker, - (int) cinfo->image_width, (int) cinfo->image_height, - cinfo->num_components); - - if (cinfo->marker->saw_SOF) - ERREXIT(cinfo, JERR_SOF_DUPLICATE); - - /* We don't support files in which the image height is initially specified */ - /* as 0 and is later redefined by DNL. As long as we have to check that, */ - /* might as well have a general sanity check. */ - if (cinfo->image_height <= 0 || cinfo->image_width <= 0 - || cinfo->num_components <= 0) - ERREXIT(cinfo, JERR_EMPTY_IMAGE); - - if (length != (cinfo->num_components * 3)) - ERREXIT(cinfo, JERR_BAD_LENGTH); - - if (cinfo->comp_info == NULL) /* do only once, even if suspend */ - cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small) - ((j_common_ptr) cinfo, JPOOL_IMAGE, - cinfo->num_components * SIZEOF(jpeg_component_info)); - - for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; - ci++, compptr++) { - compptr->component_index = ci; - INPUT_BYTE(cinfo, compptr->component_id, return FALSE); - INPUT_BYTE(cinfo, c, return FALSE); - compptr->h_samp_factor = (c >> 4) & 15; - compptr->v_samp_factor = (c ) & 15; - INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE); - - TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT, - compptr->component_id, compptr->h_samp_factor, - compptr->v_samp_factor, compptr->quant_tbl_no); - } - - cinfo->marker->saw_SOF = TRUE; - - INPUT_SYNC(cinfo); - return TRUE; -} - - -LOCAL(boolean) -get_sos (j_decompress_ptr cinfo) -/* Process a SOS marker */ -{ - INT32 length; - int i, ci, n, c, cc; - jpeg_component_info * compptr; - INPUT_VARS(cinfo); - - if (! cinfo->marker->saw_SOF) - ERREXIT(cinfo, JERR_SOS_NO_SOF); - - INPUT_2BYTES(cinfo, length, return FALSE); - - INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */ - - TRACEMS1(cinfo, 1, JTRC_SOS, n); - - if (length != (n * 2 + 6) || n > MAX_COMPS_IN_SCAN || - (n == 0 && !cinfo->progressive_mode)) - /* pseudo SOS marker only allowed in progressive mode */ - ERREXIT(cinfo, JERR_BAD_LENGTH); - - cinfo->comps_in_scan = n; - - /* Collect the component-spec parameters */ - - for (i = 0; i < n; i++) { - INPUT_BYTE(cinfo, cc, return FALSE); - INPUT_BYTE(cinfo, c, return FALSE); - - for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components; - ci++, compptr++) { - if (cc == compptr->component_id) - goto id_found; - } - - ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, cc); - - id_found: - - cinfo->cur_comp_info[i] = compptr; - compptr->dc_tbl_no = (c >> 4) & 15; - compptr->ac_tbl_no = (c ) & 15; - - TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, cc, - compptr->dc_tbl_no, compptr->ac_tbl_no); - } - - /* Collect the additional scan parameters Ss, Se, Ah/Al. */ - INPUT_BYTE(cinfo, c, return FALSE); - cinfo->Ss = c; - INPUT_BYTE(cinfo, c, return FALSE); - cinfo->Se = c; - INPUT_BYTE(cinfo, c, return FALSE); - cinfo->Ah = (c >> 4) & 15; - cinfo->Al = (c ) & 15; - - TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se, - cinfo->Ah, cinfo->Al); - - /* Prepare to scan data & restart markers */ - cinfo->marker->next_restart_num = 0; - - /* Count another (non-pseudo) SOS marker */ - if (n) cinfo->input_scan_number++; - - INPUT_SYNC(cinfo); - return TRUE; -} - - -#ifdef D_ARITH_CODING_SUPPORTED - -LOCAL(boolean) -get_dac (j_decompress_ptr cinfo) -/* Process a DAC marker */ -{ - INT32 length; - int index, val; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - - while (length > 0) { - INPUT_BYTE(cinfo, index, return FALSE); - INPUT_BYTE(cinfo, val, return FALSE); - - length -= 2; - - TRACEMS2(cinfo, 1, JTRC_DAC, index, val); - - if (index < 0 || index >= (2*NUM_ARITH_TBLS)) - ERREXIT1(cinfo, JERR_DAC_INDEX, index); - - if (index >= NUM_ARITH_TBLS) { /* define AC table */ - cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val; - } else { /* define DC table */ - cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F); - cinfo->arith_dc_U[index] = (UINT8) (val >> 4); - if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index]) - ERREXIT1(cinfo, JERR_DAC_VALUE, val); - } - } - - if (length != 0) - ERREXIT(cinfo, JERR_BAD_LENGTH); - - INPUT_SYNC(cinfo); - return TRUE; -} - -#else /* ! D_ARITH_CODING_SUPPORTED */ - -#define get_dac(cinfo) skip_variable(cinfo) - -#endif /* D_ARITH_CODING_SUPPORTED */ - - -LOCAL(boolean) -get_dht (j_decompress_ptr cinfo) -/* Process a DHT marker */ -{ - INT32 length; - UINT8 bits[17]; - UINT8 huffval[256]; - int i, index, count; - JHUFF_TBL **htblptr; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - - while (length > 16) { - INPUT_BYTE(cinfo, index, return FALSE); - - TRACEMS1(cinfo, 1, JTRC_DHT, index); - - bits[0] = 0; - count = 0; - for (i = 1; i <= 16; i++) { - INPUT_BYTE(cinfo, bits[i], return FALSE); - count += bits[i]; - } - - length -= 1 + 16; - - TRACEMS8(cinfo, 2, JTRC_HUFFBITS, - bits[1], bits[2], bits[3], bits[4], - bits[5], bits[6], bits[7], bits[8]); - TRACEMS8(cinfo, 2, JTRC_HUFFBITS, - bits[9], bits[10], bits[11], bits[12], - bits[13], bits[14], bits[15], bits[16]); - - /* Here we just do minimal validation of the counts to avoid walking - * off the end of our table space. jdhuff.c will check more carefully. - */ - if (count > 256 || ((INT32) count) > length) - ERREXIT(cinfo, JERR_BAD_HUFF_TABLE); - - for (i = 0; i < count; i++) - INPUT_BYTE(cinfo, huffval[i], return FALSE); - - length -= count; - - if (index & 0x10) { /* AC table definition */ - index -= 0x10; - htblptr = &cinfo->ac_huff_tbl_ptrs[index]; - } else { /* DC table definition */ - htblptr = &cinfo->dc_huff_tbl_ptrs[index]; - } - - if (index < 0 || index >= NUM_HUFF_TBLS) - ERREXIT1(cinfo, JERR_DHT_INDEX, index); - - if (*htblptr == NULL) - *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo); - - MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits)); - MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval)); - } - - if (length != 0) - ERREXIT(cinfo, JERR_BAD_LENGTH); - - INPUT_SYNC(cinfo); - return TRUE; -} - - -LOCAL(boolean) -get_dqt (j_decompress_ptr cinfo) -/* Process a DQT marker */ -{ - INT32 length, count, i; - int n, prec; - unsigned int tmp; - JQUANT_TBL *quant_ptr; - const int *natural_order; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - - while (length > 0) { - length--; - INPUT_BYTE(cinfo, n, return FALSE); - prec = n >> 4; - n &= 0x0F; - - TRACEMS2(cinfo, 1, JTRC_DQT, n, prec); - - if (n >= NUM_QUANT_TBLS) - ERREXIT1(cinfo, JERR_DQT_INDEX, n); - - if (cinfo->quant_tbl_ptrs[n] == NULL) - cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo); - quant_ptr = cinfo->quant_tbl_ptrs[n]; - - if (prec) { - if (length < DCTSIZE2 * 2) { - /* Initialize full table for safety. */ - for (i = 0; i < DCTSIZE2; i++) { - quant_ptr->quantval[i] = 1; - } - count = length >> 1; - } else - count = DCTSIZE2; - } else { - if (length < DCTSIZE2) { - /* Initialize full table for safety. */ - for (i = 0; i < DCTSIZE2; i++) { - quant_ptr->quantval[i] = 1; - } - count = length; - } else - count = DCTSIZE2; - } - - switch (count) { - case (2*2): natural_order = jpeg_natural_order2; break; - case (3*3): natural_order = jpeg_natural_order3; break; - case (4*4): natural_order = jpeg_natural_order4; break; - case (5*5): natural_order = jpeg_natural_order5; break; - case (6*6): natural_order = jpeg_natural_order6; break; - case (7*7): natural_order = jpeg_natural_order7; break; - default: natural_order = jpeg_natural_order; break; - } - - for (i = 0; i < count; i++) { - if (prec) - INPUT_2BYTES(cinfo, tmp, return FALSE); - else - INPUT_BYTE(cinfo, tmp, return FALSE); - /* We convert the zigzag-order table to natural array order. */ - quant_ptr->quantval[natural_order[i]] = (UINT16) tmp; - } - - if (cinfo->err->trace_level >= 2) { - for (i = 0; i < DCTSIZE2; i += 8) { - TRACEMS8(cinfo, 2, JTRC_QUANTVALS, - quant_ptr->quantval[i], quant_ptr->quantval[i+1], - quant_ptr->quantval[i+2], quant_ptr->quantval[i+3], - quant_ptr->quantval[i+4], quant_ptr->quantval[i+5], - quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]); - } - } - - length -= count; - if (prec) length -= count; - } - - if (length != 0) - ERREXIT(cinfo, JERR_BAD_LENGTH); - - INPUT_SYNC(cinfo); - return TRUE; -} - - -LOCAL(boolean) -get_dri (j_decompress_ptr cinfo) -/* Process a DRI marker */ -{ - INT32 length; - unsigned int tmp; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - - if (length != 4) - ERREXIT(cinfo, JERR_BAD_LENGTH); - - INPUT_2BYTES(cinfo, tmp, return FALSE); - - TRACEMS1(cinfo, 1, JTRC_DRI, tmp); - - cinfo->restart_interval = tmp; - - INPUT_SYNC(cinfo); - return TRUE; -} - - -/* - * Routines for processing APPn and COM markers. - * These are either saved in memory or discarded, per application request. - * APP0 and APP14 are specially checked to see if they are - * JFIF and Adobe markers, respectively. - */ - -#define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */ -#define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */ -#define APPN_DATA_LEN 14 /* Must be the largest of the above!! */ - - -LOCAL(void) -examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data, - unsigned int datalen, INT32 remaining) -/* Examine first few bytes from an APP0. - * Take appropriate action if it is a JFIF marker. - * datalen is # of bytes at data[], remaining is length of rest of marker data. - */ -{ - INT32 totallen = (INT32) datalen + remaining; - - if (datalen >= APP0_DATA_LEN && - GETJOCTET(data[0]) == 0x4A && - GETJOCTET(data[1]) == 0x46 && - GETJOCTET(data[2]) == 0x49 && - GETJOCTET(data[3]) == 0x46 && - GETJOCTET(data[4]) == 0) { - /* Found JFIF APP0 marker: save info */ - cinfo->saw_JFIF_marker = TRUE; - cinfo->JFIF_major_version = GETJOCTET(data[5]); - cinfo->JFIF_minor_version = GETJOCTET(data[6]); - cinfo->density_unit = GETJOCTET(data[7]); - cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]); - cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]); - /* Check version. - * Major version must be 1, anything else signals an incompatible change. - * (We used to treat this as an error, but now it's a nonfatal warning, - * because some bozo at Hijaak couldn't read the spec.) - * Minor version should be 0..2, but process anyway if newer. - */ - if (cinfo->JFIF_major_version != 1) - WARNMS2(cinfo, JWRN_JFIF_MAJOR, - cinfo->JFIF_major_version, cinfo->JFIF_minor_version); - /* Generate trace messages */ - TRACEMS5(cinfo, 1, JTRC_JFIF, - cinfo->JFIF_major_version, cinfo->JFIF_minor_version, - cinfo->X_density, cinfo->Y_density, cinfo->density_unit); - /* Validate thumbnail dimensions and issue appropriate messages */ - if (GETJOCTET(data[12]) | GETJOCTET(data[13])) - TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL, - GETJOCTET(data[12]), GETJOCTET(data[13])); - totallen -= APP0_DATA_LEN; - if (totallen != - ((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3)) - TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen); - } else if (datalen >= 6 && - GETJOCTET(data[0]) == 0x4A && - GETJOCTET(data[1]) == 0x46 && - GETJOCTET(data[2]) == 0x58 && - GETJOCTET(data[3]) == 0x58 && - GETJOCTET(data[4]) == 0) { - /* Found JFIF "JFXX" extension APP0 marker */ - /* The library doesn't actually do anything with these, - * but we try to produce a helpful trace message. - */ - switch (GETJOCTET(data[5])) { - case 0x10: - TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen); - break; - case 0x11: - TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen); - break; - case 0x13: - TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen); - break; - default: - TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION, - GETJOCTET(data[5]), (int) totallen); - break; - } - } else { - /* Start of APP0 does not match "JFIF" or "JFXX", or too short */ - TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen); - } -} - - -LOCAL(void) -examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data, - unsigned int datalen, INT32 remaining) -/* Examine first few bytes from an APP14. - * Take appropriate action if it is an Adobe marker. - * datalen is # of bytes at data[], remaining is length of rest of marker data. - */ -{ - unsigned int version, flags0, flags1, transform; - - if (datalen >= APP14_DATA_LEN && - GETJOCTET(data[0]) == 0x41 && - GETJOCTET(data[1]) == 0x64 && - GETJOCTET(data[2]) == 0x6F && - GETJOCTET(data[3]) == 0x62 && - GETJOCTET(data[4]) == 0x65) { - /* Found Adobe APP14 marker */ - version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]); - flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]); - flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]); - transform = GETJOCTET(data[11]); - TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform); - cinfo->saw_Adobe_marker = TRUE; - cinfo->Adobe_transform = (UINT8) transform; - } else { - /* Start of APP14 does not match "Adobe", or too short */ - TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining)); - } -} - - -METHODDEF(boolean) -get_interesting_appn (j_decompress_ptr cinfo) -/* Process an APP0 or APP14 marker without saving it */ -{ - INT32 length; - JOCTET b[APPN_DATA_LEN]; - unsigned int i, numtoread; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - - /* get the interesting part of the marker data */ - if (length >= APPN_DATA_LEN) - numtoread = APPN_DATA_LEN; - else if (length > 0) - numtoread = (unsigned int) length; - else - numtoread = 0; - for (i = 0; i < numtoread; i++) - INPUT_BYTE(cinfo, b[i], return FALSE); - length -= numtoread; - - /* process it */ - switch (cinfo->unread_marker) { - case M_APP0: - examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length); - break; - case M_APP14: - examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length); - break; - default: - /* can't get here unless jpeg_save_markers chooses wrong processor */ - ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); - break; - } - - /* skip any remaining data -- could be lots */ - INPUT_SYNC(cinfo); - if (length > 0) - (*cinfo->src->skip_input_data) (cinfo, (long) length); - - return TRUE; -} - - -#ifdef SAVE_MARKERS_SUPPORTED - -METHODDEF(boolean) -save_marker (j_decompress_ptr cinfo) -/* Save an APPn or COM marker into the marker list */ -{ - my_marker_ptr marker = (my_marker_ptr) cinfo->marker; - jpeg_saved_marker_ptr cur_marker = marker->cur_marker; - unsigned int bytes_read, data_length; - JOCTET FAR * data; - INT32 length = 0; - INPUT_VARS(cinfo); - - if (cur_marker == NULL) { - /* begin reading a marker */ - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - if (length >= 0) { /* watch out for bogus length word */ - /* figure out how much we want to save */ - unsigned int limit; - if (cinfo->unread_marker == (int) M_COM) - limit = marker->length_limit_COM; - else - limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0]; - if ((unsigned int) length < limit) - limit = (unsigned int) length; - /* allocate and initialize the marker item */ - cur_marker = (jpeg_saved_marker_ptr) - (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE, - SIZEOF(struct jpeg_marker_struct) + limit); - cur_marker->next = NULL; - cur_marker->marker = (UINT8) cinfo->unread_marker; - cur_marker->original_length = (unsigned int) length; - cur_marker->data_length = limit; - /* data area is just beyond the jpeg_marker_struct */ - data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1); - marker->cur_marker = cur_marker; - marker->bytes_read = 0; - bytes_read = 0; - data_length = limit; - } else { - /* deal with bogus length word */ - bytes_read = data_length = 0; - data = NULL; - } - } else { - /* resume reading a marker */ - bytes_read = marker->bytes_read; - data_length = cur_marker->data_length; - data = cur_marker->data + bytes_read; - } - - while (bytes_read < data_length) { - INPUT_SYNC(cinfo); /* move the restart point to here */ - marker->bytes_read = bytes_read; - /* If there's not at least one byte in buffer, suspend */ - MAKE_BYTE_AVAIL(cinfo, return FALSE); - /* Copy bytes with reasonable rapidity */ - while (bytes_read < data_length && bytes_in_buffer > 0) { - *data++ = *next_input_byte++; - bytes_in_buffer--; - bytes_read++; - } - } - - /* Done reading what we want to read */ - if (cur_marker != NULL) { /* will be NULL if bogus length word */ - /* Add new marker to end of list */ - if (cinfo->marker_list == NULL) { - cinfo->marker_list = cur_marker; - } else { - jpeg_saved_marker_ptr prev = cinfo->marker_list; - while (prev->next != NULL) - prev = prev->next; - prev->next = cur_marker; - } - /* Reset pointer & calc remaining data length */ - data = cur_marker->data; - length = cur_marker->original_length - data_length; - } - /* Reset to initial state for next marker */ - marker->cur_marker = NULL; - - /* Process the marker if interesting; else just make a generic trace msg */ - switch (cinfo->unread_marker) { - case M_APP0: - examine_app0(cinfo, data, data_length, length); - break; - case M_APP14: - examine_app14(cinfo, data, data_length, length); - break; - default: - TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, - (int) (data_length + length)); - break; - } - - /* skip any remaining data -- could be lots */ - INPUT_SYNC(cinfo); /* do before skip_input_data */ - if (length > 0) - (*cinfo->src->skip_input_data) (cinfo, (long) length); - - return TRUE; -} - -#endif /* SAVE_MARKERS_SUPPORTED */ - - -METHODDEF(boolean) -skip_variable (j_decompress_ptr cinfo) -/* Skip over an unknown or uninteresting variable-length marker */ -{ - INT32 length; - INPUT_VARS(cinfo); - - INPUT_2BYTES(cinfo, length, return FALSE); - length -= 2; - - TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length); - - INPUT_SYNC(cinfo); /* do before skip_input_data */ - if (length > 0) - (*cinfo->src->skip_input_data) (cinfo, (long) length); - - return TRUE; -} - - -/* - * Find the next JPEG marker, save it in cinfo->unread_marker. - * Returns FALSE if had to suspend before reaching a marker; - * in that case cinfo->unread_marker is unchanged. - * - * Note that the result might not be a valid marker code, - * but it will never be 0 or FF. - */ - -LOCAL(boolean) -next_marker (j_decompress_ptr cinfo) -{ - int c; - INPUT_VARS(cinfo); - - for (;;) { - INPUT_BYTE(cinfo, c, return FALSE); - /* Skip any non-FF bytes. - * This may look a bit inefficient, but it will not occur in a valid file. - * We sync after each discarded byte so that a suspending data source - * can discard the byte from its buffer. - */ - while (c != 0xFF) { - cinfo->marker->discarded_bytes++; - INPUT_SYNC(cinfo); - INPUT_BYTE(cinfo, c, return FALSE); - } - /* This loop swallows any duplicate FF bytes. Extra FFs are legal as - * pad bytes, so don't count them in discarded_bytes. We assume there - * will not be so many consecutive FF bytes as to overflow a suspending - * data source's input buffer. - */ - do { - INPUT_BYTE(cinfo, c, return FALSE); - } while (c == 0xFF); - if (c != 0) - break; /* found a valid marker, exit loop */ - /* Reach here if we found a stuffed-zero data sequence (FF/00). - * Discard it and loop back to try again. - */ - cinfo->marker->discarded_bytes += 2; - INPUT_SYNC(cinfo); - } - - if (cinfo->marker->discarded_bytes != 0) { - WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c); - cinfo->marker->discarded_bytes = 0; - } - - cinfo->unread_marker = c; - - INPUT_SYNC(cinfo); - return TRUE; -} - - -LOCAL(boolean) -first_marker (j_decompress_ptr cinfo) -/* Like next_marker, but used to obtain the initial SOI marker. */ -/* For this marker, we do not allow preceding garbage or fill; otherwise, - * we might well scan an entire input file before realizing it ain't JPEG. - * If an application wants to process non-JFIF files, it must seek to the - * SOI before calling the JPEG library. - */ -{ - int c, c2; - INPUT_VARS(cinfo); - - INPUT_BYTE(cinfo, c, return FALSE); - INPUT_BYTE(cinfo, c2, return FALSE); - if (c != 0xFF || c2 != (int) M_SOI) - ERREXIT2(cinfo, JERR_NO_SOI, c, c2); - - cinfo->unread_marker = c2; - - INPUT_SYNC(cinfo); - return TRUE; -} - - -/* - * Read markers until SOS or EOI. - * - * Returns same codes as are defined for jpeg_consume_input: - * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI. - * - * Note: This function may return a pseudo SOS marker (with zero - * component number) for treat by input controller's consume_input. - * consume_input itself should filter out (skip) the pseudo marker - * after processing for the caller. - */ - -METHODDEF(int) -read_markers (j_decompress_ptr cinfo) -{ - /* Outer loop repeats once for each marker. */ - for (;;) { - /* Collect the marker proper, unless we already did. */ - /* NB: first_marker() enforces the requirement that SOI appear first. */ - if (cinfo->unread_marker == 0) { - if (! cinfo->marker->saw_SOI) { - if (! first_marker(cinfo)) - return JPEG_SUSPENDED; - } else { - if (! next_marker(cinfo)) - return JPEG_SUSPENDED; - } - } - /* At this point cinfo->unread_marker contains the marker code and the - * input point is just past the marker proper, but before any parameters. - * A suspension will cause us to return with this state still true. - */ - switch (cinfo->unread_marker) { - case M_SOI: - if (! get_soi(cinfo)) - return JPEG_SUSPENDED; - break; - - case M_SOF0: /* Baseline */ - if (! get_sof(cinfo, TRUE, FALSE, FALSE)) - return JPEG_SUSPENDED; - break; - - case M_SOF1: /* Extended sequential, Huffman */ - if (! get_sof(cinfo, FALSE, FALSE, FALSE)) - return JPEG_SUSPENDED; - break; - - case M_SOF2: /* Progressive, Huffman */ - if (! get_sof(cinfo, FALSE, TRUE, FALSE)) - return JPEG_SUSPENDED; - break; - - case M_SOF9: /* Extended sequential, arithmetic */ - if (! get_sof(cinfo, FALSE, FALSE, TRUE)) - return JPEG_SUSPENDED; - break; - - case M_SOF10: /* Progressive, arithmetic */ - if (! get_sof(cinfo, FALSE, TRUE, TRUE)) - return JPEG_SUSPENDED; - break; - - /* Currently unsupported SOFn types */ - case M_SOF3: /* Lossless, Huffman */ - case M_SOF5: /* Differential sequential, Huffman */ - case M_SOF6: /* Differential progressive, Huffman */ - case M_SOF7: /* Differential lossless, Huffman */ - case M_JPG: /* Reserved for JPEG extensions */ - case M_SOF11: /* Lossless, arithmetic */ - case M_SOF13: /* Differential sequential, arithmetic */ - case M_SOF14: /* Differential progressive, arithmetic */ - case M_SOF15: /* Differential lossless, arithmetic */ - ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker); - break; - - case M_SOS: - if (! get_sos(cinfo)) - return JPEG_SUSPENDED; - cinfo->unread_marker = 0; /* processed the marker */ - return JPEG_REACHED_SOS; - - case M_EOI: - TRACEMS(cinfo, 1, JTRC_EOI); - cinfo->unread_marker = 0; /* processed the marker */ - return JPEG_REACHED_EOI; - - case M_DAC: - if (! get_dac(cinfo)) - return JPEG_SUSPENDED; - break; - - case M_DHT: - if (! get_dht(cinfo)) - return JPEG_SUSPENDED; - break; - - case M_DQT: - if (! get_dqt(cinfo)) - return JPEG_SUSPENDED; - break; - - case M_DRI: - if (! get_dri(cinfo)) - return JPEG_SUSPENDED; - break; - - case M_APP0: - case M_APP1: - case M_APP2: - case M_APP3: - case M_APP4: - case M_APP5: - case M_APP6: - case M_APP7: - case M_APP8: - case M_APP9: - case M_APP10: - case M_APP11: - case M_APP12: - case M_APP13: - case M_APP14: - case M_APP15: - if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[ - cinfo->unread_marker - (int) M_APP0]) (cinfo)) - return JPEG_SUSPENDED; - break; - - case M_COM: - if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo)) - return JPEG_SUSPENDED; - break; - - case M_RST0: /* these are all parameterless */ - case M_RST1: - case M_RST2: - case M_RST3: - case M_RST4: - case M_RST5: - case M_RST6: - case M_RST7: - case M_TEM: - TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker); - break; - - case M_DNL: /* Ignore DNL ... perhaps the wrong thing */ - if (! skip_variable(cinfo)) - return JPEG_SUSPENDED; - break; - - default: /* must be DHP, EXP, JPGn, or RESn */ - /* For now, we treat the reserved markers as fatal errors since they are - * likely to be used to signal incompatible JPEG Part 3 extensions. - * Once the JPEG 3 version-number marker is well defined, this code - * ought to change! - */ - ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker); - break; - } - /* Successfully processed marker, so reset state variable */ - cinfo->unread_marker = 0; - } /* end loop */ -} - - -/* - * Read a restart marker, which is expected to appear next in the datastream; - * if the marker is not there, take appropriate recovery action. - * Returns FALSE if suspension is required. - * - * This is called by the entropy decoder after it has read an appropriate - * number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder - * has already read a marker from the data source. Under normal conditions - * cinfo->unread_marker will be reset to 0 before returning; if not reset, - * it holds a marker which the decoder will be unable to read past. - */ - -METHODDEF(boolean) -read_restart_marker (j_decompress_ptr cinfo) -{ - /* Obtain a marker unless we already did. */ - /* Note that next_marker will complain if it skips any data. */ - if (cinfo->unread_marker == 0) { - if (! next_marker(cinfo)) - return FALSE; - } - - if (cinfo->unread_marker == - ((int) M_RST0 + cinfo->marker->next_restart_num)) { - /* Normal case --- swallow the marker and let entropy decoder continue */ - TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num); - cinfo->unread_marker = 0; - } else { - /* Uh-oh, the restart markers have been messed up. */ - /* Let the data source manager determine how to resync. */ - if (! (*cinfo->src->resync_to_restart) (cinfo, - cinfo->marker->next_restart_num)) - return FALSE; - } - - /* Update next-restart state */ - cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7; - - return TRUE; -} - - -/* - * This is the default resync_to_restart method for data source managers - * to use if they don't have any better approach. Some data source managers - * may be able to back up, or may have additional knowledge about the data - * which permits a more intelligent recovery strategy; such managers would - * presumably supply their own resync method. - * - * read_restart_marker calls resync_to_restart if it finds a marker other than - * the restart marker it was expecting. (This code is *not* used unless - * a nonzero restart interval has been declared.) cinfo->unread_marker is - * the marker code actually found (might be anything, except 0 or FF). - * The desired restart marker number (0..7) is passed as a parameter. - * This routine is supposed to apply whatever error recovery strategy seems - * appropriate in order to position the input stream to the next data segment. - * Note that cinfo->unread_marker is treated as a marker appearing before - * the current data-source input point; usually it should be reset to zero - * before returning. - * Returns FALSE if suspension is required. - * - * This implementation is substantially constrained by wanting to treat the - * input as a data stream; this means we can't back up. Therefore, we have - * only the following actions to work with: - * 1. Simply discard the marker and let the entropy decoder resume at next - * byte of file. - * 2. Read forward until we find another marker, discarding intervening - * data. (In theory we could look ahead within the current bufferload, - * without having to discard data if we don't find the desired marker. - * This idea is not implemented here, in part because it makes behavior - * dependent on buffer size and chance buffer-boundary positions.) - * 3. Leave the marker unread (by failing to zero cinfo->unread_marker). - * This will cause the entropy decoder to process an empty data segment, - * inserting dummy zeroes, and then we will reprocess the marker. - * - * #2 is appropriate if we think the desired marker lies ahead, while #3 is - * appropriate if the found marker is a future restart marker (indicating - * that we have missed the desired restart marker, probably because it got - * corrupted). - * We apply #2 or #3 if the found marker is a restart marker no more than - * two counts behind or ahead of the expected one. We also apply #2 if the - * found marker is not a legal JPEG marker code (it's certainly bogus data). - * If the found marker is a restart marker more than 2 counts away, we do #1 - * (too much risk that the marker is erroneous; with luck we will be able to - * resync at some future point). - * For any valid non-restart JPEG marker, we apply #3. This keeps us from - * overrunning the end of a scan. An implementation limited to single-scan - * files might find it better to apply #2 for markers other than EOI, since - * any other marker would have to be bogus data in that case. - */ - -GLOBAL(boolean) -jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired) -{ - int marker = cinfo->unread_marker; - int action = 1; - - /* Always put up a warning. */ - WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired); - - /* Outer loop handles repeated decision after scanning forward. */ - for (;;) { - if (marker < (int) M_SOF0) - action = 2; /* invalid marker */ - else if (marker < (int) M_RST0 || marker > (int) M_RST7) - action = 3; /* valid non-restart marker */ - else { - if (marker == ((int) M_RST0 + ((desired+1) & 7)) || - marker == ((int) M_RST0 + ((desired+2) & 7))) - action = 3; /* one of the next two expected restarts */ - else if (marker == ((int) M_RST0 + ((desired-1) & 7)) || - marker == ((int) M_RST0 + ((desired-2) & 7))) - action = 2; /* a prior restart, so advance */ - else - action = 1; /* desired restart or too far away */ - } - TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action); - switch (action) { - case 1: - /* Discard marker and let entropy decoder resume processing. */ - cinfo->unread_marker = 0; - return TRUE; - case 2: - /* Scan to the next marker, and repeat the decision loop. */ - if (! next_marker(cinfo)) - return FALSE; - marker = cinfo->unread_marker; - break; - case 3: - /* Return without advancing past this marker. */ - /* Entropy decoder will be forced to process an empty segment. */ - return TRUE; - } - } /* end loop */ -} - - -/* - * Reset marker processing state to begin a fresh datastream. - */ - -METHODDEF(void) -reset_marker_reader (j_decompress_ptr cinfo) -{ - my_marker_ptr marker = (my_marker_ptr) cinfo->marker; - - cinfo->comp_info = NULL; /* until allocated by get_sof */ - cinfo->input_scan_number = 0; /* no SOS seen yet */ - cinfo->unread_marker = 0; /* no pending marker */ - marker->pub.saw_SOI = FALSE; /* set internal state too */ - marker->pub.saw_SOF = FALSE; - marker->pub.discarded_bytes = 0; - marker->cur_marker = NULL; -} - - -/* - * Initialize the marker reader module. - * This is called only once, when the decompression object is created. - */ - -GLOBAL(void) -jinit_marker_reader (j_decompress_ptr cinfo) -{ - my_marker_ptr marker; - int i; - - /* Create subobject in permanent pool */ - marker = (my_marker_ptr) - (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, - SIZEOF(my_marker_reader)); - cinfo->marker = (struct jpeg_marker_reader *) marker; - /* Initialize public method pointers */ - marker->pub.reset_marker_reader = reset_marker_reader; - marker->pub.read_markers = read_markers; - marker->pub.read_restart_marker = read_restart_marker; - /* Initialize COM/APPn processing. - * By default, we examine and then discard APP0 and APP14, - * but simply discard COM and all other APPn. - */ - marker->process_COM = skip_variable; - marker->length_limit_COM = 0; - for (i = 0; i < 16; i++) { - marker->process_APPn[i] = skip_variable; - marker->length_limit_APPn[i] = 0; - } - marker->process_APPn[0] = get_interesting_appn; - marker->process_APPn[14] = get_interesting_appn; - /* Reset marker processing state */ - reset_marker_reader(cinfo); -} - - -/* - * Control saving of COM and APPn markers into marker_list. - */ - -#ifdef SAVE_MARKERS_SUPPORTED - -GLOBAL(void) -jpeg_save_markers (j_decompress_ptr cinfo, int marker_code, - unsigned int length_limit) -{ - my_marker_ptr marker = (my_marker_ptr) cinfo->marker; - long maxlength; - jpeg_marker_parser_method processor; - - /* Length limit mustn't be larger than what we can allocate - * (should only be a concern in a 16-bit environment). - */ - maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct); - if (((long) length_limit) > maxlength) - length_limit = (unsigned int) maxlength; - - /* Choose processor routine to use. - * APP0/APP14 have special requirements. - */ - if (length_limit) { - processor = save_marker; - /* If saving APP0/APP14, save at least enough for our internal use. */ - if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN) - length_limit = APP0_DATA_LEN; - else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN) - length_limit = APP14_DATA_LEN; - } else { - processor = skip_variable; - /* If discarding APP0/APP14, use our regular on-the-fly processor. */ - if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14) - processor = get_interesting_appn; - } - - if (marker_code == (int) M_COM) { - marker->process_COM = processor; - marker->length_limit_COM = length_limit; - } else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) { - marker->process_APPn[marker_code - (int) M_APP0] = processor; - marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit; - } else - ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); -} - -#endif /* SAVE_MARKERS_SUPPORTED */ - - -/* - * Install a special processing method for COM or APPn markers. - */ - -GLOBAL(void) -jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code, - jpeg_marker_parser_method routine) -{ - my_marker_ptr marker = (my_marker_ptr) cinfo->marker; - - if (marker_code == (int) M_COM) - marker->process_COM = routine; - else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) - marker->process_APPn[marker_code - (int) M_APP0] = routine; - else - ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code); -} +/*
+ * jdmarker.c
+ *
+ * Copyright (C) 1991-1998, Thomas G. Lane.
+ * Modified 2009-2012 by Guido Vollbeding.
+ * This file is part of the Independent JPEG Group's software.
+ * For conditions of distribution and use, see the accompanying README file.
+ *
+ * This file contains routines to decode JPEG datastream markers.
+ * Most of the complexity arises from our desire to support input
+ * suspension: if not all of the data for a marker is available,
+ * we must exit back to the application. On resumption, we reprocess
+ * the marker.
+ */
+
+#define JPEG_INTERNALS
+#include "jinclude.h"
+#include "jpeglib.h"
+
+
+typedef enum { /* JPEG marker codes */
+ M_SOF0 = 0xc0,
+ M_SOF1 = 0xc1,
+ M_SOF2 = 0xc2,
+ M_SOF3 = 0xc3,
+
+ M_SOF5 = 0xc5,
+ M_SOF6 = 0xc6,
+ M_SOF7 = 0xc7,
+
+ M_JPG = 0xc8,
+ M_SOF9 = 0xc9,
+ M_SOF10 = 0xca,
+ M_SOF11 = 0xcb,
+
+ M_SOF13 = 0xcd,
+ M_SOF14 = 0xce,
+ M_SOF15 = 0xcf,
+
+ M_DHT = 0xc4,
+
+ M_DAC = 0xcc,
+
+ M_RST0 = 0xd0,
+ M_RST1 = 0xd1,
+ M_RST2 = 0xd2,
+ M_RST3 = 0xd3,
+ M_RST4 = 0xd4,
+ M_RST5 = 0xd5,
+ M_RST6 = 0xd6,
+ M_RST7 = 0xd7,
+
+ M_SOI = 0xd8,
+ M_EOI = 0xd9,
+ M_SOS = 0xda,
+ M_DQT = 0xdb,
+ M_DNL = 0xdc,
+ M_DRI = 0xdd,
+ M_DHP = 0xde,
+ M_EXP = 0xdf,
+
+ M_APP0 = 0xe0,
+ M_APP1 = 0xe1,
+ M_APP2 = 0xe2,
+ M_APP3 = 0xe3,
+ M_APP4 = 0xe4,
+ M_APP5 = 0xe5,
+ M_APP6 = 0xe6,
+ M_APP7 = 0xe7,
+ M_APP8 = 0xe8,
+ M_APP9 = 0xe9,
+ M_APP10 = 0xea,
+ M_APP11 = 0xeb,
+ M_APP12 = 0xec,
+ M_APP13 = 0xed,
+ M_APP14 = 0xee,
+ M_APP15 = 0xef,
+
+ M_JPG0 = 0xf0,
+ M_JPG8 = 0xf8,
+ M_JPG13 = 0xfd,
+ M_COM = 0xfe,
+
+ M_TEM = 0x01,
+
+ M_ERROR = 0x100
+} JPEG_MARKER;
+
+
+/* Private state */
+
+typedef struct {
+ struct jpeg_marker_reader pub; /* public fields */
+
+ /* Application-overridable marker processing methods */
+ jpeg_marker_parser_method process_COM;
+ jpeg_marker_parser_method process_APPn[16];
+
+ /* Limit on marker data length to save for each marker type */
+ unsigned int length_limit_COM;
+ unsigned int length_limit_APPn[16];
+
+ /* Status of COM/APPn marker saving */
+ jpeg_saved_marker_ptr cur_marker; /* NULL if not processing a marker */
+ unsigned int bytes_read; /* data bytes read so far in marker */
+ /* Note: cur_marker is not linked into marker_list until it's all read. */
+} my_marker_reader;
+
+typedef my_marker_reader * my_marker_ptr;
+
+
+/*
+ * Macros for fetching data from the data source module.
+ *
+ * At all times, cinfo->src->next_input_byte and ->bytes_in_buffer reflect
+ * the current restart point; we update them only when we have reached a
+ * suitable place to restart if a suspension occurs.
+ */
+
+/* Declare and initialize local copies of input pointer/count */
+#define INPUT_VARS(cinfo) \
+ struct jpeg_source_mgr * datasrc = (cinfo)->src; \
+ const JOCTET * next_input_byte = datasrc->next_input_byte; \
+ size_t bytes_in_buffer = datasrc->bytes_in_buffer
+
+/* Unload the local copies --- do this only at a restart boundary */
+#define INPUT_SYNC(cinfo) \
+ ( datasrc->next_input_byte = next_input_byte, \
+ datasrc->bytes_in_buffer = bytes_in_buffer )
+
+/* Reload the local copies --- used only in MAKE_BYTE_AVAIL */
+#define INPUT_RELOAD(cinfo) \
+ ( next_input_byte = datasrc->next_input_byte, \
+ bytes_in_buffer = datasrc->bytes_in_buffer )
+
+/* Internal macro for INPUT_BYTE and INPUT_2BYTES: make a byte available.
+ * Note we do *not* do INPUT_SYNC before calling fill_input_buffer,
+ * but we must reload the local copies after a successful fill.
+ */
+#define MAKE_BYTE_AVAIL(cinfo,action) \
+ if (bytes_in_buffer == 0) { \
+ if (! (*datasrc->fill_input_buffer) (cinfo)) \
+ { action; } \
+ INPUT_RELOAD(cinfo); \
+ }
+
+/* Read a byte into variable V.
+ * If must suspend, take the specified action (typically "return FALSE").
+ */
+#define INPUT_BYTE(cinfo,V,action) \
+ MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
+ bytes_in_buffer--; \
+ V = GETJOCTET(*next_input_byte++); )
+
+/* As above, but read two bytes interpreted as an unsigned 16-bit integer.
+ * V should be declared unsigned int or perhaps INT32.
+ */
+#define INPUT_2BYTES(cinfo,V,action) \
+ MAKESTMT( MAKE_BYTE_AVAIL(cinfo,action); \
+ bytes_in_buffer--; \
+ V = ((unsigned int) GETJOCTET(*next_input_byte++)) << 8; \
+ MAKE_BYTE_AVAIL(cinfo,action); \
+ bytes_in_buffer--; \
+ V += GETJOCTET(*next_input_byte++); )
+
+
+/*
+ * Routines to process JPEG markers.
+ *
+ * Entry condition: JPEG marker itself has been read and its code saved
+ * in cinfo->unread_marker; input restart point is just after the marker.
+ *
+ * Exit: if return TRUE, have read and processed any parameters, and have
+ * updated the restart point to point after the parameters.
+ * If return FALSE, was forced to suspend before reaching end of
+ * marker parameters; restart point has not been moved. Same routine
+ * will be called again after application supplies more input data.
+ *
+ * This approach to suspension assumes that all of a marker's parameters
+ * can fit into a single input bufferload. This should hold for "normal"
+ * markers. Some COM/APPn markers might have large parameter segments
+ * that might not fit. If we are simply dropping such a marker, we use
+ * skip_input_data to get past it, and thereby put the problem on the
+ * source manager's shoulders. If we are saving the marker's contents
+ * into memory, we use a slightly different convention: when forced to
+ * suspend, the marker processor updates the restart point to the end of
+ * what it's consumed (ie, the end of the buffer) before returning FALSE.
+ * On resumption, cinfo->unread_marker still contains the marker code,
+ * but the data source will point to the next chunk of marker data.
+ * The marker processor must retain internal state to deal with this.
+ *
+ * Note that we don't bother to avoid duplicate trace messages if a
+ * suspension occurs within marker parameters. Other side effects
+ * require more care.
+ */
+
+
+LOCAL(boolean)
+get_soi (j_decompress_ptr cinfo)
+/* Process an SOI marker */
+{
+ int i;
+
+ TRACEMS(cinfo, 1, JTRC_SOI);
+
+ if (cinfo->marker->saw_SOI)
+ ERREXIT(cinfo, JERR_SOI_DUPLICATE);
+
+ /* Reset all parameters that are defined to be reset by SOI */
+
+ for (i = 0; i < NUM_ARITH_TBLS; i++) {
+ cinfo->arith_dc_L[i] = 0;
+ cinfo->arith_dc_U[i] = 1;
+ cinfo->arith_ac_K[i] = 5;
+ }
+ cinfo->restart_interval = 0;
+
+ /* Set initial assumptions for colorspace etc */
+
+ cinfo->jpeg_color_space = JCS_UNKNOWN;
+ cinfo->color_transform = JCT_NONE;
+ cinfo->CCIR601_sampling = FALSE; /* Assume non-CCIR sampling??? */
+
+ cinfo->saw_JFIF_marker = FALSE;
+ cinfo->JFIF_major_version = 1; /* set default JFIF APP0 values */
+ cinfo->JFIF_minor_version = 1;
+ cinfo->density_unit = 0;
+ cinfo->X_density = 1;
+ cinfo->Y_density = 1;
+ cinfo->saw_Adobe_marker = FALSE;
+ cinfo->Adobe_transform = 0;
+
+ cinfo->marker->saw_SOI = TRUE;
+
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+get_sof (j_decompress_ptr cinfo, boolean is_baseline, boolean is_prog,
+ boolean is_arith)
+/* Process a SOFn marker */
+{
+ INT32 length;
+ int c, ci, i;
+ jpeg_component_info * compptr;
+ INPUT_VARS(cinfo);
+
+ cinfo->is_baseline = is_baseline;
+ cinfo->progressive_mode = is_prog;
+ cinfo->arith_code = is_arith;
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+
+ INPUT_BYTE(cinfo, cinfo->data_precision, return FALSE);
+ INPUT_2BYTES(cinfo, cinfo->image_height, return FALSE);
+ INPUT_2BYTES(cinfo, cinfo->image_width, return FALSE);
+ INPUT_BYTE(cinfo, cinfo->num_components, return FALSE);
+
+ length -= 8;
+
+ TRACEMS4(cinfo, 1, JTRC_SOF, cinfo->unread_marker,
+ (int) cinfo->image_width, (int) cinfo->image_height,
+ cinfo->num_components);
+
+ if (cinfo->marker->saw_SOF)
+ ERREXIT(cinfo, JERR_SOF_DUPLICATE);
+
+ /* We don't support files in which the image height is initially specified */
+ /* as 0 and is later redefined by DNL. As long as we have to check that, */
+ /* might as well have a general sanity check. */
+ if (cinfo->image_height <= 0 || cinfo->image_width <= 0
+ || cinfo->num_components <= 0)
+ ERREXIT(cinfo, JERR_EMPTY_IMAGE);
+
+ if (length != (cinfo->num_components * 3))
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ if (cinfo->comp_info == NULL) /* do only once, even if suspend */
+ cinfo->comp_info = (jpeg_component_info *) (*cinfo->mem->alloc_small)
+ ((j_common_ptr) cinfo, JPOOL_IMAGE,
+ cinfo->num_components * SIZEOF(jpeg_component_info));
+
+ for (ci = 0; ci < cinfo->num_components; ci++) {
+ INPUT_BYTE(cinfo, c, return FALSE);
+ /* Check to see whether component id has already been seen */
+ /* (in violation of the spec, but unfortunately seen in some */
+ /* files). If so, create "fake" component id equal to the */
+ /* max id seen so far + 1. */
+ for (i = 0, compptr = cinfo->comp_info; i < ci; i++, compptr++) {
+ if (c == compptr->component_id) {
+ compptr = cinfo->comp_info;
+ c = compptr->component_id;
+ compptr++;
+ for (i = 1; i < ci; i++, compptr++) {
+ if (compptr->component_id > c) c = compptr->component_id;
+ }
+ c++;
+ break;
+ }
+ }
+ compptr->component_id = c;
+ compptr->component_index = ci;
+ INPUT_BYTE(cinfo, c, return FALSE);
+ compptr->h_samp_factor = (c >> 4) & 15;
+ compptr->v_samp_factor = (c ) & 15;
+ INPUT_BYTE(cinfo, compptr->quant_tbl_no, return FALSE);
+
+ TRACEMS4(cinfo, 1, JTRC_SOF_COMPONENT,
+ compptr->component_id, compptr->h_samp_factor,
+ compptr->v_samp_factor, compptr->quant_tbl_no);
+ }
+
+ cinfo->marker->saw_SOF = TRUE;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+get_sos (j_decompress_ptr cinfo)
+/* Process a SOS marker */
+{
+ INT32 length;
+ int c, ci, i, n;
+ jpeg_component_info * compptr;
+ INPUT_VARS(cinfo);
+
+ if (! cinfo->marker->saw_SOF)
+ ERREXITS(cinfo, JERR_SOF_BEFORE, "SOS");
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+
+ INPUT_BYTE(cinfo, n, return FALSE); /* Number of components */
+
+ TRACEMS1(cinfo, 1, JTRC_SOS, n);
+
+ if (length != (n * 2 + 6) || n > MAX_COMPS_IN_SCAN ||
+ (n == 0 && !cinfo->progressive_mode))
+ /* pseudo SOS marker only allowed in progressive mode */
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ cinfo->comps_in_scan = n;
+
+ /* Collect the component-spec parameters */
+
+ for (i = 0; i < n; i++) {
+ INPUT_BYTE(cinfo, c, return FALSE);
+
+ /* Detect the case where component id's are not unique, and, if so, */
+ /* create a fake component id using the same logic as in get_sof. */
+ for (ci = 0; ci < i; ci++) {
+ if (c == cinfo->cur_comp_info[ci]->component_id) {
+ c = cinfo->cur_comp_info[0]->component_id;
+ for (ci = 1; ci < i; ci++) {
+ compptr = cinfo->cur_comp_info[ci];
+ if (compptr->component_id > c) c = compptr->component_id;
+ }
+ c++;
+ break;
+ }
+ }
+
+ for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
+ ci++, compptr++) {
+ if (c == compptr->component_id)
+ goto id_found;
+ }
+
+ ERREXIT1(cinfo, JERR_BAD_COMPONENT_ID, c);
+
+ id_found:
+
+ cinfo->cur_comp_info[i] = compptr;
+ INPUT_BYTE(cinfo, c, return FALSE);
+ compptr->dc_tbl_no = (c >> 4) & 15;
+ compptr->ac_tbl_no = (c ) & 15;
+
+ TRACEMS3(cinfo, 1, JTRC_SOS_COMPONENT, compptr->component_id,
+ compptr->dc_tbl_no, compptr->ac_tbl_no);
+ }
+
+ /* Collect the additional scan parameters Ss, Se, Ah/Al. */
+ INPUT_BYTE(cinfo, c, return FALSE);
+ cinfo->Ss = c;
+ INPUT_BYTE(cinfo, c, return FALSE);
+ cinfo->Se = c;
+ INPUT_BYTE(cinfo, c, return FALSE);
+ cinfo->Ah = (c >> 4) & 15;
+ cinfo->Al = (c ) & 15;
+
+ TRACEMS4(cinfo, 1, JTRC_SOS_PARAMS, cinfo->Ss, cinfo->Se,
+ cinfo->Ah, cinfo->Al);
+
+ /* Prepare to scan data & restart markers */
+ cinfo->marker->next_restart_num = 0;
+
+ /* Count another (non-pseudo) SOS marker */
+ if (n) cinfo->input_scan_number++;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+#ifdef D_ARITH_CODING_SUPPORTED
+
+LOCAL(boolean)
+get_dac (j_decompress_ptr cinfo)
+/* Process a DAC marker */
+{
+ INT32 length;
+ int index, val;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+
+ while (length > 0) {
+ INPUT_BYTE(cinfo, index, return FALSE);
+ INPUT_BYTE(cinfo, val, return FALSE);
+
+ length -= 2;
+
+ TRACEMS2(cinfo, 1, JTRC_DAC, index, val);
+
+ if (index < 0 || index >= (2*NUM_ARITH_TBLS))
+ ERREXIT1(cinfo, JERR_DAC_INDEX, index);
+
+ if (index >= NUM_ARITH_TBLS) { /* define AC table */
+ cinfo->arith_ac_K[index-NUM_ARITH_TBLS] = (UINT8) val;
+ } else { /* define DC table */
+ cinfo->arith_dc_L[index] = (UINT8) (val & 0x0F);
+ cinfo->arith_dc_U[index] = (UINT8) (val >> 4);
+ if (cinfo->arith_dc_L[index] > cinfo->arith_dc_U[index])
+ ERREXIT1(cinfo, JERR_DAC_VALUE, val);
+ }
+ }
+
+ if (length != 0)
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+#else /* ! D_ARITH_CODING_SUPPORTED */
+
+#define get_dac(cinfo) skip_variable(cinfo)
+
+#endif /* D_ARITH_CODING_SUPPORTED */
+
+
+LOCAL(boolean)
+get_dht (j_decompress_ptr cinfo)
+/* Process a DHT marker */
+{
+ INT32 length;
+ UINT8 bits[17];
+ UINT8 huffval[256];
+ int i, index, count;
+ JHUFF_TBL **htblptr;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+
+ while (length > 16) {
+ INPUT_BYTE(cinfo, index, return FALSE);
+
+ TRACEMS1(cinfo, 1, JTRC_DHT, index);
+
+ bits[0] = 0;
+ count = 0;
+ for (i = 1; i <= 16; i++) {
+ INPUT_BYTE(cinfo, bits[i], return FALSE);
+ count += bits[i];
+ }
+
+ length -= 1 + 16;
+
+ TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
+ bits[1], bits[2], bits[3], bits[4],
+ bits[5], bits[6], bits[7], bits[8]);
+ TRACEMS8(cinfo, 2, JTRC_HUFFBITS,
+ bits[9], bits[10], bits[11], bits[12],
+ bits[13], bits[14], bits[15], bits[16]);
+
+ /* Here we just do minimal validation of the counts to avoid walking
+ * off the end of our table space. jdhuff.c will check more carefully.
+ */
+ if (count > 256 || ((INT32) count) > length)
+ ERREXIT(cinfo, JERR_BAD_HUFF_TABLE);
+
+ for (i = 0; i < count; i++)
+ INPUT_BYTE(cinfo, huffval[i], return FALSE);
+
+ length -= count;
+
+ if (index & 0x10) { /* AC table definition */
+ index -= 0x10;
+ htblptr = &cinfo->ac_huff_tbl_ptrs[index];
+ } else { /* DC table definition */
+ htblptr = &cinfo->dc_huff_tbl_ptrs[index];
+ }
+
+ if (index < 0 || index >= NUM_HUFF_TBLS)
+ ERREXIT1(cinfo, JERR_DHT_INDEX, index);
+
+ if (*htblptr == NULL)
+ *htblptr = jpeg_alloc_huff_table((j_common_ptr) cinfo);
+
+ MEMCOPY((*htblptr)->bits, bits, SIZEOF((*htblptr)->bits));
+ MEMCOPY((*htblptr)->huffval, huffval, SIZEOF((*htblptr)->huffval));
+ }
+
+ if (length != 0)
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+get_dqt (j_decompress_ptr cinfo)
+/* Process a DQT marker */
+{
+ INT32 length, count, i;
+ int n, prec;
+ unsigned int tmp;
+ JQUANT_TBL *quant_ptr;
+ const int *natural_order;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+
+ while (length > 0) {
+ length--;
+ INPUT_BYTE(cinfo, n, return FALSE);
+ prec = n >> 4;
+ n &= 0x0F;
+
+ TRACEMS2(cinfo, 1, JTRC_DQT, n, prec);
+
+ if (n >= NUM_QUANT_TBLS)
+ ERREXIT1(cinfo, JERR_DQT_INDEX, n);
+
+ if (cinfo->quant_tbl_ptrs[n] == NULL)
+ cinfo->quant_tbl_ptrs[n] = jpeg_alloc_quant_table((j_common_ptr) cinfo);
+ quant_ptr = cinfo->quant_tbl_ptrs[n];
+
+ if (prec) {
+ if (length < DCTSIZE2 * 2) {
+ /* Initialize full table for safety. */
+ for (i = 0; i < DCTSIZE2; i++) {
+ quant_ptr->quantval[i] = 1;
+ }
+ count = length >> 1;
+ } else
+ count = DCTSIZE2;
+ } else {
+ if (length < DCTSIZE2) {
+ /* Initialize full table for safety. */
+ for (i = 0; i < DCTSIZE2; i++) {
+ quant_ptr->quantval[i] = 1;
+ }
+ count = length;
+ } else
+ count = DCTSIZE2;
+ }
+
+ switch (count) {
+ case (2*2): natural_order = jpeg_natural_order2; break;
+ case (3*3): natural_order = jpeg_natural_order3; break;
+ case (4*4): natural_order = jpeg_natural_order4; break;
+ case (5*5): natural_order = jpeg_natural_order5; break;
+ case (6*6): natural_order = jpeg_natural_order6; break;
+ case (7*7): natural_order = jpeg_natural_order7; break;
+ default: natural_order = jpeg_natural_order; break;
+ }
+
+ for (i = 0; i < count; i++) {
+ if (prec)
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ else
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ /* We convert the zigzag-order table to natural array order. */
+ quant_ptr->quantval[natural_order[i]] = (UINT16) tmp;
+ }
+
+ if (cinfo->err->trace_level >= 2) {
+ for (i = 0; i < DCTSIZE2; i += 8) {
+ TRACEMS8(cinfo, 2, JTRC_QUANTVALS,
+ quant_ptr->quantval[i], quant_ptr->quantval[i+1],
+ quant_ptr->quantval[i+2], quant_ptr->quantval[i+3],
+ quant_ptr->quantval[i+4], quant_ptr->quantval[i+5],
+ quant_ptr->quantval[i+6], quant_ptr->quantval[i+7]);
+ }
+ }
+
+ length -= count;
+ if (prec) length -= count;
+ }
+
+ if (length != 0)
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+get_dri (j_decompress_ptr cinfo)
+/* Process a DRI marker */
+{
+ INT32 length;
+ unsigned int tmp;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+
+ if (length != 4)
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+
+ TRACEMS1(cinfo, 1, JTRC_DRI, tmp);
+
+ cinfo->restart_interval = tmp;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+get_lse (j_decompress_ptr cinfo)
+/* Process an LSE marker */
+{
+ INT32 length;
+ unsigned int tmp;
+ int cid;
+ INPUT_VARS(cinfo);
+
+ if (! cinfo->marker->saw_SOF)
+ ERREXITS(cinfo, JERR_SOF_BEFORE, "LSE");
+
+ if (cinfo->num_components < 3) goto bad;
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+
+ if (length != 24)
+ ERREXIT(cinfo, JERR_BAD_LENGTH);
+
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ if (tmp != 0x0D) /* ID inverse transform specification */
+ ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != MAXJSAMPLE) goto bad; /* MAXTRANS */
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ if (tmp != 3) goto bad; /* Nt=3 */
+ INPUT_BYTE(cinfo, cid, return FALSE);
+ if (cid != cinfo->comp_info[1].component_id) goto bad;
+ INPUT_BYTE(cinfo, cid, return FALSE);
+ if (cid != cinfo->comp_info[0].component_id) goto bad;
+ INPUT_BYTE(cinfo, cid, return FALSE);
+ if (cid != cinfo->comp_info[2].component_id) goto bad;
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ if (tmp != 0x80) goto bad; /* F1: CENTER1=1, NORM1=0 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 0) goto bad; /* A(1,1)=0 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 0) goto bad; /* A(1,2)=0 */
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ if (tmp != 0) goto bad; /* F2: CENTER2=0, NORM2=0 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 1) goto bad; /* A(2,1)=1 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 0) goto bad; /* A(2,2)=0 */
+ INPUT_BYTE(cinfo, tmp, return FALSE);
+ if (tmp != 0) goto bad; /* F3: CENTER3=0, NORM3=0 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 1) goto bad; /* A(3,1)=1 */
+ INPUT_2BYTES(cinfo, tmp, return FALSE);
+ if (tmp != 0) { /* A(3,2)=0 */
+ bad:
+ ERREXIT(cinfo, JERR_CONVERSION_NOTIMPL);
+ }
+
+ /* OK, valid transform that we can handle. */
+ cinfo->color_transform = JCT_SUBTRACT_GREEN;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+/*
+ * Routines for processing APPn and COM markers.
+ * These are either saved in memory or discarded, per application request.
+ * APP0 and APP14 are specially checked to see if they are
+ * JFIF and Adobe markers, respectively.
+ */
+
+#define APP0_DATA_LEN 14 /* Length of interesting data in APP0 */
+#define APP14_DATA_LEN 12 /* Length of interesting data in APP14 */
+#define APPN_DATA_LEN 14 /* Must be the largest of the above!! */
+
+
+LOCAL(void)
+examine_app0 (j_decompress_ptr cinfo, JOCTET FAR * data,
+ unsigned int datalen, INT32 remaining)
+/* Examine first few bytes from an APP0.
+ * Take appropriate action if it is a JFIF marker.
+ * datalen is # of bytes at data[], remaining is length of rest of marker data.
+ */
+{
+ INT32 totallen = (INT32) datalen + remaining;
+
+ if (datalen >= APP0_DATA_LEN &&
+ GETJOCTET(data[0]) == 0x4A &&
+ GETJOCTET(data[1]) == 0x46 &&
+ GETJOCTET(data[2]) == 0x49 &&
+ GETJOCTET(data[3]) == 0x46 &&
+ GETJOCTET(data[4]) == 0) {
+ /* Found JFIF APP0 marker: save info */
+ cinfo->saw_JFIF_marker = TRUE;
+ cinfo->JFIF_major_version = GETJOCTET(data[5]);
+ cinfo->JFIF_minor_version = GETJOCTET(data[6]);
+ cinfo->density_unit = GETJOCTET(data[7]);
+ cinfo->X_density = (GETJOCTET(data[8]) << 8) + GETJOCTET(data[9]);
+ cinfo->Y_density = (GETJOCTET(data[10]) << 8) + GETJOCTET(data[11]);
+ /* Check version.
+ * Major version must be 1, anything else signals an incompatible change.
+ * (We used to treat this as an error, but now it's a nonfatal warning,
+ * because some bozo at Hijaak couldn't read the spec.)
+ * Minor version should be 0..2, but process anyway if newer.
+ */
+ if (cinfo->JFIF_major_version != 1)
+ WARNMS2(cinfo, JWRN_JFIF_MAJOR,
+ cinfo->JFIF_major_version, cinfo->JFIF_minor_version);
+ /* Generate trace messages */
+ TRACEMS5(cinfo, 1, JTRC_JFIF,
+ cinfo->JFIF_major_version, cinfo->JFIF_minor_version,
+ cinfo->X_density, cinfo->Y_density, cinfo->density_unit);
+ /* Validate thumbnail dimensions and issue appropriate messages */
+ if (GETJOCTET(data[12]) | GETJOCTET(data[13]))
+ TRACEMS2(cinfo, 1, JTRC_JFIF_THUMBNAIL,
+ GETJOCTET(data[12]), GETJOCTET(data[13]));
+ totallen -= APP0_DATA_LEN;
+ if (totallen !=
+ ((INT32)GETJOCTET(data[12]) * (INT32)GETJOCTET(data[13]) * (INT32) 3))
+ TRACEMS1(cinfo, 1, JTRC_JFIF_BADTHUMBNAILSIZE, (int) totallen);
+ } else if (datalen >= 6 &&
+ GETJOCTET(data[0]) == 0x4A &&
+ GETJOCTET(data[1]) == 0x46 &&
+ GETJOCTET(data[2]) == 0x58 &&
+ GETJOCTET(data[3]) == 0x58 &&
+ GETJOCTET(data[4]) == 0) {
+ /* Found JFIF "JFXX" extension APP0 marker */
+ /* The library doesn't actually do anything with these,
+ * but we try to produce a helpful trace message.
+ */
+ switch (GETJOCTET(data[5])) {
+ case 0x10:
+ TRACEMS1(cinfo, 1, JTRC_THUMB_JPEG, (int) totallen);
+ break;
+ case 0x11:
+ TRACEMS1(cinfo, 1, JTRC_THUMB_PALETTE, (int) totallen);
+ break;
+ case 0x13:
+ TRACEMS1(cinfo, 1, JTRC_THUMB_RGB, (int) totallen);
+ break;
+ default:
+ TRACEMS2(cinfo, 1, JTRC_JFIF_EXTENSION,
+ GETJOCTET(data[5]), (int) totallen);
+ break;
+ }
+ } else {
+ /* Start of APP0 does not match "JFIF" or "JFXX", or too short */
+ TRACEMS1(cinfo, 1, JTRC_APP0, (int) totallen);
+ }
+}
+
+
+LOCAL(void)
+examine_app14 (j_decompress_ptr cinfo, JOCTET FAR * data,
+ unsigned int datalen, INT32 remaining)
+/* Examine first few bytes from an APP14.
+ * Take appropriate action if it is an Adobe marker.
+ * datalen is # of bytes at data[], remaining is length of rest of marker data.
+ */
+{
+ unsigned int version, flags0, flags1, transform;
+
+ if (datalen >= APP14_DATA_LEN &&
+ GETJOCTET(data[0]) == 0x41 &&
+ GETJOCTET(data[1]) == 0x64 &&
+ GETJOCTET(data[2]) == 0x6F &&
+ GETJOCTET(data[3]) == 0x62 &&
+ GETJOCTET(data[4]) == 0x65) {
+ /* Found Adobe APP14 marker */
+ version = (GETJOCTET(data[5]) << 8) + GETJOCTET(data[6]);
+ flags0 = (GETJOCTET(data[7]) << 8) + GETJOCTET(data[8]);
+ flags1 = (GETJOCTET(data[9]) << 8) + GETJOCTET(data[10]);
+ transform = GETJOCTET(data[11]);
+ TRACEMS4(cinfo, 1, JTRC_ADOBE, version, flags0, flags1, transform);
+ cinfo->saw_Adobe_marker = TRUE;
+ cinfo->Adobe_transform = (UINT8) transform;
+ } else {
+ /* Start of APP14 does not match "Adobe", or too short */
+ TRACEMS1(cinfo, 1, JTRC_APP14, (int) (datalen + remaining));
+ }
+}
+
+
+METHODDEF(boolean)
+get_interesting_appn (j_decompress_ptr cinfo)
+/* Process an APP0 or APP14 marker without saving it */
+{
+ INT32 length;
+ JOCTET b[APPN_DATA_LEN];
+ unsigned int i, numtoread;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+
+ /* get the interesting part of the marker data */
+ if (length >= APPN_DATA_LEN)
+ numtoread = APPN_DATA_LEN;
+ else if (length > 0)
+ numtoread = (unsigned int) length;
+ else
+ numtoread = 0;
+ for (i = 0; i < numtoread; i++)
+ INPUT_BYTE(cinfo, b[i], return FALSE);
+ length -= numtoread;
+
+ /* process it */
+ switch (cinfo->unread_marker) {
+ case M_APP0:
+ examine_app0(cinfo, (JOCTET FAR *) b, numtoread, length);
+ break;
+ case M_APP14:
+ examine_app14(cinfo, (JOCTET FAR *) b, numtoread, length);
+ break;
+ default:
+ /* can't get here unless jpeg_save_markers chooses wrong processor */
+ ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
+ break;
+ }
+
+ /* skip any remaining data -- could be lots */
+ INPUT_SYNC(cinfo);
+ if (length > 0)
+ (*cinfo->src->skip_input_data) (cinfo, (long) length);
+
+ return TRUE;
+}
+
+
+#ifdef SAVE_MARKERS_SUPPORTED
+
+METHODDEF(boolean)
+save_marker (j_decompress_ptr cinfo)
+/* Save an APPn or COM marker into the marker list */
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+ jpeg_saved_marker_ptr cur_marker = marker->cur_marker;
+ unsigned int bytes_read, data_length;
+ JOCTET FAR * data;
+ INT32 length = 0;
+ INPUT_VARS(cinfo);
+
+ if (cur_marker == NULL) {
+ /* begin reading a marker */
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+ if (length >= 0) { /* watch out for bogus length word */
+ /* figure out how much we want to save */
+ unsigned int limit;
+ if (cinfo->unread_marker == (int) M_COM)
+ limit = marker->length_limit_COM;
+ else
+ limit = marker->length_limit_APPn[cinfo->unread_marker - (int) M_APP0];
+ if ((unsigned int) length < limit)
+ limit = (unsigned int) length;
+ /* allocate and initialize the marker item */
+ cur_marker = (jpeg_saved_marker_ptr)
+ (*cinfo->mem->alloc_large) ((j_common_ptr) cinfo, JPOOL_IMAGE,
+ SIZEOF(struct jpeg_marker_struct) + limit);
+ cur_marker->next = NULL;
+ cur_marker->marker = (UINT8) cinfo->unread_marker;
+ cur_marker->original_length = (unsigned int) length;
+ cur_marker->data_length = limit;
+ /* data area is just beyond the jpeg_marker_struct */
+ data = cur_marker->data = (JOCTET FAR *) (cur_marker + 1);
+ marker->cur_marker = cur_marker;
+ marker->bytes_read = 0;
+ bytes_read = 0;
+ data_length = limit;
+ } else {
+ /* deal with bogus length word */
+ bytes_read = data_length = 0;
+ data = NULL;
+ }
+ } else {
+ /* resume reading a marker */
+ bytes_read = marker->bytes_read;
+ data_length = cur_marker->data_length;
+ data = cur_marker->data + bytes_read;
+ }
+
+ while (bytes_read < data_length) {
+ INPUT_SYNC(cinfo); /* move the restart point to here */
+ marker->bytes_read = bytes_read;
+ /* If there's not at least one byte in buffer, suspend */
+ MAKE_BYTE_AVAIL(cinfo, return FALSE);
+ /* Copy bytes with reasonable rapidity */
+ while (bytes_read < data_length && bytes_in_buffer > 0) {
+ *data++ = *next_input_byte++;
+ bytes_in_buffer--;
+ bytes_read++;
+ }
+ }
+
+ /* Done reading what we want to read */
+ if (cur_marker != NULL) { /* will be NULL if bogus length word */
+ /* Add new marker to end of list */
+ if (cinfo->marker_list == NULL) {
+ cinfo->marker_list = cur_marker;
+ } else {
+ jpeg_saved_marker_ptr prev = cinfo->marker_list;
+ while (prev->next != NULL)
+ prev = prev->next;
+ prev->next = cur_marker;
+ }
+ /* Reset pointer & calc remaining data length */
+ data = cur_marker->data;
+ length = cur_marker->original_length - data_length;
+ }
+ /* Reset to initial state for next marker */
+ marker->cur_marker = NULL;
+
+ /* Process the marker if interesting; else just make a generic trace msg */
+ switch (cinfo->unread_marker) {
+ case M_APP0:
+ examine_app0(cinfo, data, data_length, length);
+ break;
+ case M_APP14:
+ examine_app14(cinfo, data, data_length, length);
+ break;
+ default:
+ TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker,
+ (int) (data_length + length));
+ break;
+ }
+
+ /* skip any remaining data -- could be lots */
+ INPUT_SYNC(cinfo); /* do before skip_input_data */
+ if (length > 0)
+ (*cinfo->src->skip_input_data) (cinfo, (long) length);
+
+ return TRUE;
+}
+
+#endif /* SAVE_MARKERS_SUPPORTED */
+
+
+METHODDEF(boolean)
+skip_variable (j_decompress_ptr cinfo)
+/* Skip over an unknown or uninteresting variable-length marker */
+{
+ INT32 length;
+ INPUT_VARS(cinfo);
+
+ INPUT_2BYTES(cinfo, length, return FALSE);
+ length -= 2;
+
+ TRACEMS2(cinfo, 1, JTRC_MISC_MARKER, cinfo->unread_marker, (int) length);
+
+ INPUT_SYNC(cinfo); /* do before skip_input_data */
+ if (length > 0)
+ (*cinfo->src->skip_input_data) (cinfo, (long) length);
+
+ return TRUE;
+}
+
+
+/*
+ * Find the next JPEG marker, save it in cinfo->unread_marker.
+ * Returns FALSE if had to suspend before reaching a marker;
+ * in that case cinfo->unread_marker is unchanged.
+ *
+ * Note that the result might not be a valid marker code,
+ * but it will never be 0 or FF.
+ */
+
+LOCAL(boolean)
+next_marker (j_decompress_ptr cinfo)
+{
+ int c;
+ INPUT_VARS(cinfo);
+
+ for (;;) {
+ INPUT_BYTE(cinfo, c, return FALSE);
+ /* Skip any non-FF bytes.
+ * This may look a bit inefficient, but it will not occur in a valid file.
+ * We sync after each discarded byte so that a suspending data source
+ * can discard the byte from its buffer.
+ */
+ while (c != 0xFF) {
+ cinfo->marker->discarded_bytes++;
+ INPUT_SYNC(cinfo);
+ INPUT_BYTE(cinfo, c, return FALSE);
+ }
+ /* This loop swallows any duplicate FF bytes. Extra FFs are legal as
+ * pad bytes, so don't count them in discarded_bytes. We assume there
+ * will not be so many consecutive FF bytes as to overflow a suspending
+ * data source's input buffer.
+ */
+ do {
+ INPUT_BYTE(cinfo, c, return FALSE);
+ } while (c == 0xFF);
+ if (c != 0)
+ break; /* found a valid marker, exit loop */
+ /* Reach here if we found a stuffed-zero data sequence (FF/00).
+ * Discard it and loop back to try again.
+ */
+ cinfo->marker->discarded_bytes += 2;
+ INPUT_SYNC(cinfo);
+ }
+
+ if (cinfo->marker->discarded_bytes != 0) {
+ WARNMS2(cinfo, JWRN_EXTRANEOUS_DATA, cinfo->marker->discarded_bytes, c);
+ cinfo->marker->discarded_bytes = 0;
+ }
+
+ cinfo->unread_marker = c;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+LOCAL(boolean)
+first_marker (j_decompress_ptr cinfo)
+/* Like next_marker, but used to obtain the initial SOI marker. */
+/* For this marker, we do not allow preceding garbage or fill; otherwise,
+ * we might well scan an entire input file before realizing it ain't JPEG.
+ * If an application wants to process non-JFIF files, it must seek to the
+ * SOI before calling the JPEG library.
+ */
+{
+ int c, c2;
+ INPUT_VARS(cinfo);
+
+ INPUT_BYTE(cinfo, c, return FALSE);
+ INPUT_BYTE(cinfo, c2, return FALSE);
+ if (c != 0xFF || c2 != (int) M_SOI)
+ ERREXIT2(cinfo, JERR_NO_SOI, c, c2);
+
+ cinfo->unread_marker = c2;
+
+ INPUT_SYNC(cinfo);
+ return TRUE;
+}
+
+
+/*
+ * Read markers until SOS or EOI.
+ *
+ * Returns same codes as are defined for jpeg_consume_input:
+ * JPEG_SUSPENDED, JPEG_REACHED_SOS, or JPEG_REACHED_EOI.
+ *
+ * Note: This function may return a pseudo SOS marker (with zero
+ * component number) for treat by input controller's consume_input.
+ * consume_input itself should filter out (skip) the pseudo marker
+ * after processing for the caller.
+ */
+
+METHODDEF(int)
+read_markers (j_decompress_ptr cinfo)
+{
+ /* Outer loop repeats once for each marker. */
+ for (;;) {
+ /* Collect the marker proper, unless we already did. */
+ /* NB: first_marker() enforces the requirement that SOI appear first. */
+ if (cinfo->unread_marker == 0) {
+ if (! cinfo->marker->saw_SOI) {
+ if (! first_marker(cinfo))
+ return JPEG_SUSPENDED;
+ } else {
+ if (! next_marker(cinfo))
+ return JPEG_SUSPENDED;
+ }
+ }
+ /* At this point cinfo->unread_marker contains the marker code and the
+ * input point is just past the marker proper, but before any parameters.
+ * A suspension will cause us to return with this state still true.
+ */
+ switch (cinfo->unread_marker) {
+ case M_SOI:
+ if (! get_soi(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_SOF0: /* Baseline */
+ if (! get_sof(cinfo, TRUE, FALSE, FALSE))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_SOF1: /* Extended sequential, Huffman */
+ if (! get_sof(cinfo, FALSE, FALSE, FALSE))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_SOF2: /* Progressive, Huffman */
+ if (! get_sof(cinfo, FALSE, TRUE, FALSE))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_SOF9: /* Extended sequential, arithmetic */
+ if (! get_sof(cinfo, FALSE, FALSE, TRUE))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_SOF10: /* Progressive, arithmetic */
+ if (! get_sof(cinfo, FALSE, TRUE, TRUE))
+ return JPEG_SUSPENDED;
+ break;
+
+ /* Currently unsupported SOFn types */
+ case M_SOF3: /* Lossless, Huffman */
+ case M_SOF5: /* Differential sequential, Huffman */
+ case M_SOF6: /* Differential progressive, Huffman */
+ case M_SOF7: /* Differential lossless, Huffman */
+ case M_JPG: /* Reserved for JPEG extensions */
+ case M_SOF11: /* Lossless, arithmetic */
+ case M_SOF13: /* Differential sequential, arithmetic */
+ case M_SOF14: /* Differential progressive, arithmetic */
+ case M_SOF15: /* Differential lossless, arithmetic */
+ ERREXIT1(cinfo, JERR_SOF_UNSUPPORTED, cinfo->unread_marker);
+ break;
+
+ case M_SOS:
+ if (! get_sos(cinfo))
+ return JPEG_SUSPENDED;
+ cinfo->unread_marker = 0; /* processed the marker */
+ return JPEG_REACHED_SOS;
+
+ case M_EOI:
+ TRACEMS(cinfo, 1, JTRC_EOI);
+ cinfo->unread_marker = 0; /* processed the marker */
+ return JPEG_REACHED_EOI;
+
+ case M_DAC:
+ if (! get_dac(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_DHT:
+ if (! get_dht(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_DQT:
+ if (! get_dqt(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_DRI:
+ if (! get_dri(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_JPG8:
+ if (! get_lse(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_APP0:
+ case M_APP1:
+ case M_APP2:
+ case M_APP3:
+ case M_APP4:
+ case M_APP5:
+ case M_APP6:
+ case M_APP7:
+ case M_APP8:
+ case M_APP9:
+ case M_APP10:
+ case M_APP11:
+ case M_APP12:
+ case M_APP13:
+ case M_APP14:
+ case M_APP15:
+ if (! (*((my_marker_ptr) cinfo->marker)->process_APPn[
+ cinfo->unread_marker - (int) M_APP0]) (cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_COM:
+ if (! (*((my_marker_ptr) cinfo->marker)->process_COM) (cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ case M_RST0: /* these are all parameterless */
+ case M_RST1:
+ case M_RST2:
+ case M_RST3:
+ case M_RST4:
+ case M_RST5:
+ case M_RST6:
+ case M_RST7:
+ case M_TEM:
+ TRACEMS1(cinfo, 1, JTRC_PARMLESS_MARKER, cinfo->unread_marker);
+ break;
+
+ case M_DNL: /* Ignore DNL ... perhaps the wrong thing */
+ if (! skip_variable(cinfo))
+ return JPEG_SUSPENDED;
+ break;
+
+ default: /* must be DHP, EXP, JPGn, or RESn */
+ /* For now, we treat the reserved markers as fatal errors since they are
+ * likely to be used to signal incompatible JPEG Part 3 extensions.
+ * Once the JPEG 3 version-number marker is well defined, this code
+ * ought to change!
+ */
+ ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, cinfo->unread_marker);
+ break;
+ }
+ /* Successfully processed marker, so reset state variable */
+ cinfo->unread_marker = 0;
+ } /* end loop */
+}
+
+
+/*
+ * Read a restart marker, which is expected to appear next in the datastream;
+ * if the marker is not there, take appropriate recovery action.
+ * Returns FALSE if suspension is required.
+ *
+ * This is called by the entropy decoder after it has read an appropriate
+ * number of MCUs. cinfo->unread_marker may be nonzero if the entropy decoder
+ * has already read a marker from the data source. Under normal conditions
+ * cinfo->unread_marker will be reset to 0 before returning; if not reset,
+ * it holds a marker which the decoder will be unable to read past.
+ */
+
+METHODDEF(boolean)
+read_restart_marker (j_decompress_ptr cinfo)
+{
+ /* Obtain a marker unless we already did. */
+ /* Note that next_marker will complain if it skips any data. */
+ if (cinfo->unread_marker == 0) {
+ if (! next_marker(cinfo))
+ return FALSE;
+ }
+
+ if (cinfo->unread_marker ==
+ ((int) M_RST0 + cinfo->marker->next_restart_num)) {
+ /* Normal case --- swallow the marker and let entropy decoder continue */
+ TRACEMS1(cinfo, 3, JTRC_RST, cinfo->marker->next_restart_num);
+ cinfo->unread_marker = 0;
+ } else {
+ /* Uh-oh, the restart markers have been messed up. */
+ /* Let the data source manager determine how to resync. */
+ if (! (*cinfo->src->resync_to_restart) (cinfo,
+ cinfo->marker->next_restart_num))
+ return FALSE;
+ }
+
+ /* Update next-restart state */
+ cinfo->marker->next_restart_num = (cinfo->marker->next_restart_num + 1) & 7;
+
+ return TRUE;
+}
+
+
+/*
+ * This is the default resync_to_restart method for data source managers
+ * to use if they don't have any better approach. Some data source managers
+ * may be able to back up, or may have additional knowledge about the data
+ * which permits a more intelligent recovery strategy; such managers would
+ * presumably supply their own resync method.
+ *
+ * read_restart_marker calls resync_to_restart if it finds a marker other than
+ * the restart marker it was expecting. (This code is *not* used unless
+ * a nonzero restart interval has been declared.) cinfo->unread_marker is
+ * the marker code actually found (might be anything, except 0 or FF).
+ * The desired restart marker number (0..7) is passed as a parameter.
+ * This routine is supposed to apply whatever error recovery strategy seems
+ * appropriate in order to position the input stream to the next data segment.
+ * Note that cinfo->unread_marker is treated as a marker appearing before
+ * the current data-source input point; usually it should be reset to zero
+ * before returning.
+ * Returns FALSE if suspension is required.
+ *
+ * This implementation is substantially constrained by wanting to treat the
+ * input as a data stream; this means we can't back up. Therefore, we have
+ * only the following actions to work with:
+ * 1. Simply discard the marker and let the entropy decoder resume at next
+ * byte of file.
+ * 2. Read forward until we find another marker, discarding intervening
+ * data. (In theory we could look ahead within the current bufferload,
+ * without having to discard data if we don't find the desired marker.
+ * This idea is not implemented here, in part because it makes behavior
+ * dependent on buffer size and chance buffer-boundary positions.)
+ * 3. Leave the marker unread (by failing to zero cinfo->unread_marker).
+ * This will cause the entropy decoder to process an empty data segment,
+ * inserting dummy zeroes, and then we will reprocess the marker.
+ *
+ * #2 is appropriate if we think the desired marker lies ahead, while #3 is
+ * appropriate if the found marker is a future restart marker (indicating
+ * that we have missed the desired restart marker, probably because it got
+ * corrupted).
+ * We apply #2 or #3 if the found marker is a restart marker no more than
+ * two counts behind or ahead of the expected one. We also apply #2 if the
+ * found marker is not a legal JPEG marker code (it's certainly bogus data).
+ * If the found marker is a restart marker more than 2 counts away, we do #1
+ * (too much risk that the marker is erroneous; with luck we will be able to
+ * resync at some future point).
+ * For any valid non-restart JPEG marker, we apply #3. This keeps us from
+ * overrunning the end of a scan. An implementation limited to single-scan
+ * files might find it better to apply #2 for markers other than EOI, since
+ * any other marker would have to be bogus data in that case.
+ */
+
+GLOBAL(boolean)
+jpeg_resync_to_restart (j_decompress_ptr cinfo, int desired)
+{
+ int marker = cinfo->unread_marker;
+ int action = 1;
+
+ /* Always put up a warning. */
+ WARNMS2(cinfo, JWRN_MUST_RESYNC, marker, desired);
+
+ /* Outer loop handles repeated decision after scanning forward. */
+ for (;;) {
+ if (marker < (int) M_SOF0)
+ action = 2; /* invalid marker */
+ else if (marker < (int) M_RST0 || marker > (int) M_RST7)
+ action = 3; /* valid non-restart marker */
+ else {
+ if (marker == ((int) M_RST0 + ((desired+1) & 7)) ||
+ marker == ((int) M_RST0 + ((desired+2) & 7)))
+ action = 3; /* one of the next two expected restarts */
+ else if (marker == ((int) M_RST0 + ((desired-1) & 7)) ||
+ marker == ((int) M_RST0 + ((desired-2) & 7)))
+ action = 2; /* a prior restart, so advance */
+ else
+ action = 1; /* desired restart or too far away */
+ }
+ TRACEMS2(cinfo, 4, JTRC_RECOVERY_ACTION, marker, action);
+ switch (action) {
+ case 1:
+ /* Discard marker and let entropy decoder resume processing. */
+ cinfo->unread_marker = 0;
+ return TRUE;
+ case 2:
+ /* Scan to the next marker, and repeat the decision loop. */
+ if (! next_marker(cinfo))
+ return FALSE;
+ marker = cinfo->unread_marker;
+ break;
+ case 3:
+ /* Return without advancing past this marker. */
+ /* Entropy decoder will be forced to process an empty segment. */
+ return TRUE;
+ }
+ } /* end loop */
+}
+
+
+/*
+ * Reset marker processing state to begin a fresh datastream.
+ */
+
+METHODDEF(void)
+reset_marker_reader (j_decompress_ptr cinfo)
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+
+ cinfo->comp_info = NULL; /* until allocated by get_sof */
+ cinfo->input_scan_number = 0; /* no SOS seen yet */
+ cinfo->unread_marker = 0; /* no pending marker */
+ marker->pub.saw_SOI = FALSE; /* set internal state too */
+ marker->pub.saw_SOF = FALSE;
+ marker->pub.discarded_bytes = 0;
+ marker->cur_marker = NULL;
+}
+
+
+/*
+ * Initialize the marker reader module.
+ * This is called only once, when the decompression object is created.
+ */
+
+GLOBAL(void)
+jinit_marker_reader (j_decompress_ptr cinfo)
+{
+ my_marker_ptr marker;
+ int i;
+
+ /* Create subobject in permanent pool */
+ marker = (my_marker_ptr)
+ (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT,
+ SIZEOF(my_marker_reader));
+ cinfo->marker = &marker->pub;
+ /* Initialize public method pointers */
+ marker->pub.reset_marker_reader = reset_marker_reader;
+ marker->pub.read_markers = read_markers;
+ marker->pub.read_restart_marker = read_restart_marker;
+ /* Initialize COM/APPn processing.
+ * By default, we examine and then discard APP0 and APP14,
+ * but simply discard COM and all other APPn.
+ */
+ marker->process_COM = skip_variable;
+ marker->length_limit_COM = 0;
+ for (i = 0; i < 16; i++) {
+ marker->process_APPn[i] = skip_variable;
+ marker->length_limit_APPn[i] = 0;
+ }
+ marker->process_APPn[0] = get_interesting_appn;
+ marker->process_APPn[14] = get_interesting_appn;
+ /* Reset marker processing state */
+ reset_marker_reader(cinfo);
+}
+
+
+/*
+ * Control saving of COM and APPn markers into marker_list.
+ */
+
+#ifdef SAVE_MARKERS_SUPPORTED
+
+GLOBAL(void)
+jpeg_save_markers (j_decompress_ptr cinfo, int marker_code,
+ unsigned int length_limit)
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+ long maxlength;
+ jpeg_marker_parser_method processor;
+
+ /* Length limit mustn't be larger than what we can allocate
+ * (should only be a concern in a 16-bit environment).
+ */
+ maxlength = cinfo->mem->max_alloc_chunk - SIZEOF(struct jpeg_marker_struct);
+ if (((long) length_limit) > maxlength)
+ length_limit = (unsigned int) maxlength;
+
+ /* Choose processor routine to use.
+ * APP0/APP14 have special requirements.
+ */
+ if (length_limit) {
+ processor = save_marker;
+ /* If saving APP0/APP14, save at least enough for our internal use. */
+ if (marker_code == (int) M_APP0 && length_limit < APP0_DATA_LEN)
+ length_limit = APP0_DATA_LEN;
+ else if (marker_code == (int) M_APP14 && length_limit < APP14_DATA_LEN)
+ length_limit = APP14_DATA_LEN;
+ } else {
+ processor = skip_variable;
+ /* If discarding APP0/APP14, use our regular on-the-fly processor. */
+ if (marker_code == (int) M_APP0 || marker_code == (int) M_APP14)
+ processor = get_interesting_appn;
+ }
+
+ if (marker_code == (int) M_COM) {
+ marker->process_COM = processor;
+ marker->length_limit_COM = length_limit;
+ } else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15) {
+ marker->process_APPn[marker_code - (int) M_APP0] = processor;
+ marker->length_limit_APPn[marker_code - (int) M_APP0] = length_limit;
+ } else
+ ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code);
+}
+
+#endif /* SAVE_MARKERS_SUPPORTED */
+
+
+/*
+ * Install a special processing method for COM or APPn markers.
+ */
+
+GLOBAL(void)
+jpeg_set_marker_processor (j_decompress_ptr cinfo, int marker_code,
+ jpeg_marker_parser_method routine)
+{
+ my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
+
+ if (marker_code == (int) M_COM)
+ marker->process_COM = routine;
+ else if (marker_code >= (int) M_APP0 && marker_code <= (int) M_APP15)
+ marker->process_APPn[marker_code - (int) M_APP0] = routine;
+ else
+ ERREXIT1(cinfo, JERR_UNKNOWN_MARKER, marker_code);
+}
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