170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * jdatasrc.c 370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Copyright (C) 1994-1996, Thomas G. Lane. 570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This file is part of the Independent JPEG Group's software. 670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * For conditions of distribution and use, see the accompanying README file. 770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This file contains decompression data source routines for the case of 970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * reading JPEG data from a file (or any stdio stream). While these routines 1070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * are sufficient for most applications, some will want to use a different 1170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * source manager. 1270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * IMPORTANT: we assume that fread() will correctly transcribe an array of 1370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * JOCTETs from 8-bit-wide elements on external storage. If char is wider 1470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * than 8 bits on your machine, you may need to do some tweaking. 1570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 1670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 1770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* this is not a core library module, so it doesn't define JPEG_INTERNALS */ 1870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#include "jinclude.h" 1970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#include "jpeglib.h" 2070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#include "jerror.h" 2170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* Expanded data source object for stdio input */ 2470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinetypedef struct { 2670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine struct jpeg_source_mgr pub; /* public fields */ 2770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 2870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine FILE * infile; /* source stream */ 2970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine JOCTET * buffer; /* start of buffer */ 3070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine boolean start_of_file; /* have we gotten any data yet? */ 3170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} my_source_mgr; 3270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 3370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinetypedef my_source_mgr * my_src_ptr; 3470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 3570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine#define INPUT_BUF_SIZE 4096 /* choose an efficiently fread'able size */ 3670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 3770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 3870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 3970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Initialize source --- called by jpeg_read_header 4070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * before any data is actually read. 4170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 4270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 4370a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineMETHODDEF(void) 4470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkineinit_source (j_decompress_ptr cinfo) 4570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 4670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine my_src_ptr src = (my_src_ptr) cinfo->src; 4770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 4870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* We reset the empty-input-file flag for each image, 4970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * but we don't clear the input buffer. 5070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This is correct behavior for reading a series of images from one source. 5170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 5270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->start_of_file = TRUE; 5370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 5470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 5570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 5670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 5770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Fill the input buffer --- called whenever buffer is emptied. 5870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 5970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * In typical applications, this should read fresh data into the buffer 6070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * (ignoring the current state of next_input_byte & bytes_in_buffer), 6170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * reset the pointer & count to the start of the buffer, and return TRUE 6270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * indicating that the buffer has been reloaded. It is not necessary to 6370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * fill the buffer entirely, only to obtain at least one more byte. 6470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 6570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * There is no such thing as an EOF return. If the end of the file has been 6670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * reached, the routine has a choice of ERREXIT() or inserting fake data into 6770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the buffer. In most cases, generating a warning message and inserting a 6870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * fake EOI marker is the best course of action --- this will allow the 6970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * decompressor to output however much of the image is there. However, 7070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the resulting error message is misleading if the real problem is an empty 7170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * input file, so we handle that case specially. 7270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 7370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * In applications that need to be able to suspend compression due to input 7470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * not being available yet, a FALSE return indicates that no more data can be 7570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * obtained right now, but more may be forthcoming later. In this situation, 7670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the decompressor will return to its caller (with an indication of the 7770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * number of scanlines it has read, if any). The application should resume 7870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * decompression after it has loaded more data into the input buffer. Note 7970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * that there are substantial restrictions on the use of suspension --- see 8070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the documentation. 8170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 8270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * When suspending, the decompressor will back up to a convenient restart point 8370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * (typically the start of the current MCU). next_input_byte & bytes_in_buffer 8470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * indicate where the restart point will be if the current call returns FALSE. 8570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Data beyond this point must be rescanned after resumption, so move it to 8670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * the front of the buffer rather than discarding it. 8770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 8870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 8970a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineMETHODDEF(boolean) 9070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinefill_input_buffer (j_decompress_ptr cinfo) 9170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 9270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine my_src_ptr src = (my_src_ptr) cinfo->src; 9370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine size_t nbytes; 9470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 9570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine nbytes = JFREAD(src->infile, src->buffer, INPUT_BUF_SIZE); 9670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 9770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (nbytes <= 0) { 9870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (src->start_of_file) /* Treat empty input file as fatal error */ 9970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine ERREXIT(cinfo, JERR_INPUT_EMPTY); 10070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine WARNMS(cinfo, JWRN_JPEG_EOF); 10170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Insert a fake EOI marker */ 10270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->buffer[0] = (JOCTET) 0xFF; 10370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->buffer[1] = (JOCTET) JPEG_EOI; 10470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine nbytes = 2; 10570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 10670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 10770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.next_input_byte = src->buffer; 10870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.bytes_in_buffer = nbytes; 10970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->start_of_file = FALSE; 11070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine return TRUE; 11270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 11370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 11570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 11670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Skip data --- used to skip over a potentially large amount of 11770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * uninteresting data (such as an APPn marker). 11870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 11970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Writers of suspendable-input applications must note that skip_input_data 12070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * is not granted the right to give a suspension return. If the skip extends 12170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * beyond the data currently in the buffer, the buffer can be marked empty so 12270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * that the next read will cause a fill_input_buffer call that can suspend. 12370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Arranging for additional bytes to be discarded before reloading the input 12470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * buffer is the application writer's problem. 12570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 12670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 12770a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineMETHODDEF(void) 12870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkineskip_input_data (j_decompress_ptr cinfo, long num_bytes) 12970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 13070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine my_src_ptr src = (my_src_ptr) cinfo->src; 13170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 13270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* Just a dumb implementation for now. Could use fseek() except 13370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * it doesn't work on pipes. Not clear that being smart is worth 13470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * any trouble anyway --- large skips are infrequent. 13570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 13670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (num_bytes > 0) { 13770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine while (num_bytes > (long) src->pub.bytes_in_buffer) { 13870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine num_bytes -= (long) src->pub.bytes_in_buffer; 13970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (void) fill_input_buffer(cinfo); 14070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* note we assume that fill_input_buffer will never return FALSE, 14170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * so suspension need not be handled. 14270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 14370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 14470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.next_input_byte += (size_t) num_bytes; 14570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.bytes_in_buffer -= (size_t) num_bytes; 14670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 14770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 14870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 14970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 15070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 15170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * An additional method that can be provided by data source modules is the 15270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * resync_to_restart method for error recovery in the presence of RST markers. 15370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * For the moment, this source module just uses the default resync method 15470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * provided by the JPEG library. That method assumes that no backtracking 15570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * is possible. 15670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 15770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 15870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 15970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 16070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Terminate source --- called by jpeg_finish_decompress 16170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * after all data has been read. Often a no-op. 16270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * 16370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * NB: *not* called by jpeg_abort or jpeg_destroy; surrounding 16470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * application must deal with any cleanup that should happen even 16570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * for error exit. 16670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 16770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 16870a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineMETHODDEF(void) 16970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkineterm_source (j_decompress_ptr cinfo) 17070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 17170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* no work necessary here */ 17270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 17370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 17470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 17570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine/* 17670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * Prepare for input from a stdio stream. 17770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * The caller must have already opened the stream, and is responsible 17870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * for closing it after finishing decompression. 17970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 18070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 18170a18cd874a22452aca9e39e22275ed4538ed20bVladimir ChtchetkineGLOBAL(void) 18270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkinejpeg_stdio_src (j_decompress_ptr cinfo, FILE * infile) 18370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine{ 18470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine my_src_ptr src; 18570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 18670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine /* The source object and input buffer are made permanent so that a series 18770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * of JPEG images can be read from the same file by calling jpeg_stdio_src 18870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * only before the first one. (If we discarded the buffer at the end of 18970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * one image, we'd likely lose the start of the next one.) 19070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * This makes it unsafe to use this manager and a different source 19170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine * manager serially with the same JPEG object. Caveat programmer. 19270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine */ 19370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine if (cinfo->src == NULL) { /* first time for this JPEG object? */ 19470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine cinfo->src = (struct jpeg_source_mgr *) 19570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, 19670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine SIZEOF(my_source_mgr)); 19770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src = (my_src_ptr) cinfo->src; 19870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->buffer = (JOCTET *) 19970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_PERMANENT, 20070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine INPUT_BUF_SIZE * SIZEOF(JOCTET)); 20170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine } 20270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine 20370a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src = (my_src_ptr) cinfo->src; 20470a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.init_source = init_source; 20570a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.fill_input_buffer = fill_input_buffer; 20670a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.skip_input_data = skip_input_data; 20770a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.resync_to_restart = jpeg_resync_to_restart; /* use default method */ 20870a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.term_source = term_source; 20970a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->infile = infile; 21070a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.bytes_in_buffer = 0; /* forces fill_input_buffer on first read */ 21170a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine src->pub.next_input_byte = NULL; /* until buffer loaded */ 21270a18cd874a22452aca9e39e22275ed4538ed20bVladimir Chtchetkine} 213