Bug Summary

File:jdk/src/java.desktop/share/native/libjavajpeg/jcmarker.c
Warning:line 161, column 9
Array access (via field 'quantval') results in a null pointer dereference

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name jcmarker.c -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -setup-static-analyzer -mrelocation-model pic -pic-level 2 -mthread-model posix -fno-delete-null-pointer-checks -mframe-pointer=all -relaxed-aliasing -fmath-errno -fno-rounding-math -masm-verbose -mconstructor-aliases -munwind-tables -target-cpu x86-64 -dwarf-column-info -fno-split-dwarf-inlining -debugger-tuning=gdb -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/modules_include/java.base/linux -I /home/daniel/Projects/java/jdk/src/java.base/share/native/libjava -I /home/daniel/Projects/java/jdk/src/java.base/unix/native/libjava -I /home/daniel/Projects/java/jdk/src/hotspot/share/include -I /home/daniel/Projects/java/jdk/src/hotspot/os/posix/include -D LIBC=gnu -D _GNU_SOURCE -D _REENTRANT -D _LARGEFILE64_SOURCE -D LINUX -D DEBUG -D _LITTLE_ENDIAN -D ARCH="amd64" -D amd64 -D _LP64=1 -I /home/daniel/Projects/java/jdk/src/java.desktop/share/native/libjavajpeg -I /home/daniel/Projects/java/jdk/build/linux-x86_64-server-fastdebug/support/headers/java.desktop -D _FORTIFY_SOURCE=2 -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O3 -Wno-unused-parameter -Wno-unused -Wno-clobbered -Wno-implicit-fallthrough -Wno-shift-negative-value -Wno-array-bounds -std=c99 -fdebug-compilation-dir /home/daniel/Projects/java/jdk/make -ferror-limit 19 -fmessage-length 0 -fvisibility hidden -stack-protector 1 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -faddrsig -o /home/daniel/Projects/java/scan/2021-12-21-193737-8510-1 -x c /home/daniel/Projects/java/jdk/src/java.desktop/share/native/libjavajpeg/jcmarker.c
1/*
2 * reserved comment block
3 * DO NOT REMOVE OR ALTER!
4 */
5/*
6 * jcmarker.c
7 *
8 * Copyright (C) 1991-1998, Thomas G. Lane.
9 * This file is part of the Independent JPEG Group's software.
10 * For conditions of distribution and use, see the accompanying README file.
11 *
12 * This file contains routines to write JPEG datastream markers.
13 */
14
15#define JPEG_INTERNALS
16#include "jinclude.h"
17#include "jpeglib.h"
18
19
20typedef enum { /* JPEG marker codes */
21 M_SOF0 = 0xc0,
22 M_SOF1 = 0xc1,
23 M_SOF2 = 0xc2,
24 M_SOF3 = 0xc3,
25
26 M_SOF5 = 0xc5,
27 M_SOF6 = 0xc6,
28 M_SOF7 = 0xc7,
29
30 M_JPG = 0xc8,
31 M_SOF9 = 0xc9,
32 M_SOF10 = 0xca,
33 M_SOF11 = 0xcb,
34
35 M_SOF13 = 0xcd,
36 M_SOF14 = 0xce,
37 M_SOF15 = 0xcf,
38
39 M_DHT = 0xc4,
40
41 M_DAC = 0xcc,
42
43 M_RST0 = 0xd0,
44 M_RST1 = 0xd1,
45 M_RST2 = 0xd2,
46 M_RST3 = 0xd3,
47 M_RST4 = 0xd4,
48 M_RST5 = 0xd5,
49 M_RST6 = 0xd6,
50 M_RST7 = 0xd7,
51
52 M_SOI = 0xd8,
53 M_EOI = 0xd9,
54 M_SOS = 0xda,
55 M_DQT = 0xdb,
56 M_DNL = 0xdc,
57 M_DRI = 0xdd,
58 M_DHP = 0xde,
59 M_EXP = 0xdf,
60
61 M_APP0 = 0xe0,
62 M_APP1 = 0xe1,
63 M_APP2 = 0xe2,
64 M_APP3 = 0xe3,
65 M_APP4 = 0xe4,
66 M_APP5 = 0xe5,
67 M_APP6 = 0xe6,
68 M_APP7 = 0xe7,
69 M_APP8 = 0xe8,
70 M_APP9 = 0xe9,
71 M_APP10 = 0xea,
72 M_APP11 = 0xeb,
73 M_APP12 = 0xec,
74 M_APP13 = 0xed,
75 M_APP14 = 0xee,
76 M_APP15 = 0xef,
77
78 M_JPG0 = 0xf0,
79 M_JPG13 = 0xfd,
80 M_COM = 0xfe,
81
82 M_TEM = 0x01,
83
84 M_ERROR = 0x100
85} JPEG_MARKER;
86
87
88/* Private state */
89
90typedef struct {
91 struct jpeg_marker_writer pub; /* public fields */
92
93 unsigned int last_restart_interval; /* last DRI value emitted; 0 after SOI */
94} my_marker_writer;
95
96typedef my_marker_writer * my_marker_ptr;
97
98
99/*
100 * Basic output routines.
101 *
102 * Note that we do not support suspension while writing a marker.
103 * Therefore, an application using suspension must ensure that there is
104 * enough buffer space for the initial markers (typ. 600-700 bytes) before
105 * calling jpeg_start_compress, and enough space to write the trailing EOI
106 * (a few bytes) before calling jpeg_finish_compress. Multipass compression
107 * modes are not supported at all with suspension, so those two are the only
108 * points where markers will be written.
109 */
110
111LOCAL(void)static void
112emit_byte (j_compress_ptr cinfo, int val)
113/* Emit a byte */
114{
115 struct jpeg_destination_mgr * dest = cinfo->dest;
116
117 *(dest->next_output_byte)++ = (JOCTET) val;
118 if (--dest->free_in_buffer == 0) {
119 if (! (*dest->empty_output_buffer) (cinfo))
120 ERREXIT(cinfo, JERR_CANT_SUSPEND)((cinfo)->err->msg_code = (JERR_CANT_SUSPEND), (*(cinfo
)->err->error_exit) ((j_common_ptr) (cinfo)));
121 }
122}
123
124
125LOCAL(void)static void
126emit_marker (j_compress_ptr cinfo, JPEG_MARKER mark)
127/* Emit a marker code */
128{
129 emit_byte(cinfo, 0xFF);
130 emit_byte(cinfo, (int) mark);
131}
132
133
134LOCAL(void)static void
135emit_2bytes (j_compress_ptr cinfo, int value)
136/* Emit a 2-byte integer; these are always MSB first in JPEG files */
137{
138 emit_byte(cinfo, (value >> 8) & 0xFF);
139 emit_byte(cinfo, value & 0xFF);
140}
141
142
143/*
144 * Routines to write specific marker types.
145 */
146
147LOCAL(int)static int
148emit_dqt (j_compress_ptr cinfo, int index)
149/* Emit a DQT marker */
150/* Returns the precision used (0 = 8bits, 1 = 16bits) for baseline checking */
151{
152 JQUANT_TBL * qtbl = cinfo->quant_tbl_ptrs[index];
5
←
'qtbl' initialized here
→
153 int prec;
154 int i;
155
156 if (qtbl == NULL((void*)0))
6
←
Assuming 'qtbl' is equal to NULL
→
7
←
Taking true branch
→
157 ERREXIT1(cinfo, JERR_NO_QUANT_TABLE, index)((cinfo)->err->msg_code = (JERR_NO_QUANT_TABLE), (cinfo
)->err->msg_parm.i[0] = (index), (*(cinfo)->err->
error_exit) ((j_common_ptr) (cinfo)));
158
159 prec = 0;
160 for (i = 0; i < DCTSIZE264; i++) {
8
←
Loop condition is true. Entering loop body
→
161 if (qtbl->quantval[i] > 255)
9
←
Array access (via field 'quantval') results in a null pointer dereference
162 prec = 1;
163 }
164
165 if (! qtbl->sent_table) {
166 emit_marker(cinfo, M_DQT);
167
168 emit_2bytes(cinfo, prec ? DCTSIZE264*2 + 1 + 2 : DCTSIZE264 + 1 + 2);
169
170 emit_byte(cinfo, index + (prec<<4));
171
172 for (i = 0; i < DCTSIZE264; i++) {
173 /* The table entries must be emitted in zigzag order. */
174 unsigned int qval = qtbl->quantval[jpeg_natural_orderjZAGTable[i]];
175 if (prec)
176 emit_byte(cinfo, (int) (qval >> 8));
177 emit_byte(cinfo, (int) (qval & 0xFF));
178 }
179
180 qtbl->sent_table = TRUE1;
181 }
182
183 return prec;
184}
185
186
187LOCAL(void)static void
188emit_dht (j_compress_ptr cinfo, int index, boolean is_ac)
189/* Emit a DHT marker */
190{
191 JHUFF_TBL * htbl;
192 int length, i;
193
194 if (is_ac) {
195 htbl = cinfo->ac_huff_tbl_ptrs[index];
196 index += 0x10; /* output index has AC bit set */
197 } else {
198 htbl = cinfo->dc_huff_tbl_ptrs[index];
199 }
200
201 if (htbl == NULL((void*)0))
202 ERREXIT1(cinfo, JERR_NO_HUFF_TABLE, index)((cinfo)->err->msg_code = (JERR_NO_HUFF_TABLE), (cinfo)
->err->msg_parm.i[0] = (index), (*(cinfo)->err->error_exit
) ((j_common_ptr) (cinfo)));
203
204 if (! htbl->sent_table) {
205 emit_marker(cinfo, M_DHT);
206
207 length = 0;
208 for (i = 1; i <= 16; i++)
209 length += htbl->bits[i];
210
211 emit_2bytes(cinfo, length + 2 + 1 + 16);
212 emit_byte(cinfo, index);
213
214 for (i = 1; i <= 16; i++)
215 emit_byte(cinfo, htbl->bits[i]);
216
217 for (i = 0; i < length; i++)
218 emit_byte(cinfo, htbl->huffval[i]);
219
220 htbl->sent_table = TRUE1;
221 }
222}
223
224
225LOCAL(void)static void
226emit_dac (j_compress_ptr cinfo)
227/* Emit a DAC marker */
228/* Since the useful info is so small, we want to emit all the tables in */
229/* one DAC marker. Therefore this routine does its own scan of the table. */
230{
231#ifdef C_ARITH_CODING_SUPPORTED
232 char dc_in_use[NUM_ARITH_TBLS16];
233 char ac_in_use[NUM_ARITH_TBLS16];
234 int length, i;
235 jpeg_component_info *compptr;
236
237 for (i = 0; i < NUM_ARITH_TBLS16; i++)
238 dc_in_use[i] = ac_in_use[i] = 0;
239
240 for (i = 0; i < cinfo->comps_in_scan; i++) {
241 compptr = cinfo->cur_comp_info[i];
242 dc_in_use[compptr->dc_tbl_no] = 1;
243 ac_in_use[compptr->ac_tbl_no] = 1;
244 }
245
246 length = 0;
247 for (i = 0; i < NUM_ARITH_TBLS16; i++)
248 length += dc_in_use[i] + ac_in_use[i];
249
250 emit_marker(cinfo, M_DAC);
251
252 emit_2bytes(cinfo, length*2 + 2);
253
254 for (i = 0; i < NUM_ARITH_TBLS16; i++) {
255 if (dc_in_use[i]) {
256 emit_byte(cinfo, i);
257 emit_byte(cinfo, cinfo->arith_dc_L[i] + (cinfo->arith_dc_U[i]<<4));
258 }
259 if (ac_in_use[i]) {
260 emit_byte(cinfo, i + 0x10);
261 emit_byte(cinfo, cinfo->arith_ac_K[i]);
262 }
263 }
264#endif /* C_ARITH_CODING_SUPPORTED */
265}
266
267
268LOCAL(void)static void
269emit_dri (j_compress_ptr cinfo)
270/* Emit a DRI marker */
271{
272 emit_marker(cinfo, M_DRI);
273
274 emit_2bytes(cinfo, 4); /* fixed length */
275
276 emit_2bytes(cinfo, (int) cinfo->restart_interval);
277}
278
279
280LOCAL(void)static void
281emit_sof (j_compress_ptr cinfo, JPEG_MARKER code)
282/* Emit a SOF marker */
283{
284 int ci;
285 jpeg_component_info *compptr;
286
287 emit_marker(cinfo, code);
288
289 emit_2bytes(cinfo, 3 * cinfo->num_components + 2 + 5 + 1); /* length */
290
291 /* Make sure image isn't bigger than SOF field can handle */
292 if ((long) cinfo->image_height > 65535L ||
293 (long) cinfo->image_width > 65535L)
294 ERREXIT1(cinfo, JERR_IMAGE_TOO_BIG, (unsigned int) 65535)((cinfo)->err->msg_code = (JERR_IMAGE_TOO_BIG), (cinfo)
->err->msg_parm.i[0] = ((unsigned int) 65535), (*(cinfo
)->err->error_exit) ((j_common_ptr) (cinfo)));
295
296 emit_byte(cinfo, cinfo->data_precision);
297 emit_2bytes(cinfo, (int) cinfo->image_height);
298 emit_2bytes(cinfo, (int) cinfo->image_width);
299
300 emit_byte(cinfo, cinfo->num_components);
301
302 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
303 ci++, compptr++) {
304 emit_byte(cinfo, compptr->component_id);
305 emit_byte(cinfo, (compptr->h_samp_factor << 4) + compptr->v_samp_factor);
306 emit_byte(cinfo, compptr->quant_tbl_no);
307 }
308}
309
310
311LOCAL(void)static void
312emit_sos (j_compress_ptr cinfo)
313/* Emit a SOS marker */
314{
315 int i, td, ta;
316 jpeg_component_info *compptr;
317
318 emit_marker(cinfo, M_SOS);
319
320 emit_2bytes(cinfo, 2 * cinfo->comps_in_scan + 2 + 1 + 3); /* length */
321
322 emit_byte(cinfo, cinfo->comps_in_scan);
323
324 for (i = 0; i < cinfo->comps_in_scan; i++) {
325 compptr = cinfo->cur_comp_info[i];
326 emit_byte(cinfo, compptr->component_id);
327 td = compptr->dc_tbl_no;
328 ta = compptr->ac_tbl_no;
329 if (cinfo->progressive_mode) {
330 /* Progressive mode: only DC or only AC tables are used in one scan;
331 * furthermore, Huffman coding of DC refinement uses no table at all.
332 * We emit 0 for unused field(s); this is recommended by the P&M text
333 * but does not seem to be specified in the standard.
334 */
335 if (cinfo->Ss == 0) {
336 ta = 0; /* DC scan */
337 if (cinfo->Ah != 0 && !cinfo->arith_code)
338 td = 0; /* no DC table either */
339 } else {
340 td = 0; /* AC scan */
341 }
342 }
343 emit_byte(cinfo, (td << 4) + ta);
344 }
345
346 emit_byte(cinfo, cinfo->Ss);
347 emit_byte(cinfo, cinfo->Se);
348 emit_byte(cinfo, (cinfo->Ah << 4) + cinfo->Al);
349}
350
351
352LOCAL(void)static void
353emit_jfif_app0 (j_compress_ptr cinfo)
354/* Emit a JFIF-compliant APP0 marker */
355{
356 /*
357 * Length of APP0 block (2 bytes)
358 * Block ID (4 bytes - ASCII "JFIF")
359 * Zero byte (1 byte to terminate the ID string)
360 * Version Major, Minor (2 bytes - major first)
361 * Units (1 byte - 0x00 = none, 0x01 = inch, 0x02 = cm)
362 * Xdpu (2 bytes - dots per unit horizontal)
363 * Ydpu (2 bytes - dots per unit vertical)
364 * Thumbnail X size (1 byte)
365 * Thumbnail Y size (1 byte)
366 */
367
368 emit_marker(cinfo, M_APP0);
369
370 emit_2bytes(cinfo, 2 + 4 + 1 + 2 + 1 + 2 + 2 + 1 + 1); /* length */
371
372 emit_byte(cinfo, 0x4A); /* Identifier: ASCII "JFIF" */
373 emit_byte(cinfo, 0x46);
374 emit_byte(cinfo, 0x49);
375 emit_byte(cinfo, 0x46);
376 emit_byte(cinfo, 0);
377 emit_byte(cinfo, cinfo->JFIF_major_version); /* Version fields */
378 emit_byte(cinfo, cinfo->JFIF_minor_version);
379 emit_byte(cinfo, cinfo->density_unit); /* Pixel size information */
380 emit_2bytes(cinfo, (int) cinfo->X_density);
381 emit_2bytes(cinfo, (int) cinfo->Y_density);
382 emit_byte(cinfo, 0); /* No thumbnail image */
383 emit_byte(cinfo, 0);
384}
385
386
387LOCAL(void)static void
388emit_adobe_app14 (j_compress_ptr cinfo)
389/* Emit an Adobe APP14 marker */
390{
391 /*
392 * Length of APP14 block (2 bytes)
393 * Block ID (5 bytes - ASCII "Adobe")
394 * Version Number (2 bytes - currently 100)
395 * Flags0 (2 bytes - currently 0)
396 * Flags1 (2 bytes - currently 0)
397 * Color transform (1 byte)
398 *
399 * Although Adobe TN 5116 mentions Version = 101, all the Adobe files
400 * now in circulation seem to use Version = 100, so that's what we write.
401 *
402 * We write the color transform byte as 1 if the JPEG color space is
403 * YCbCr, 2 if it's YCCK, 0 otherwise. Adobe's definition has to do with
404 * whether the encoder performed a transformation, which is pretty useless.
405 */
406
407 emit_marker(cinfo, M_APP14);
408
409 emit_2bytes(cinfo, 2 + 5 + 2 + 2 + 2 + 1); /* length */
410
411 emit_byte(cinfo, 0x41); /* Identifier: ASCII "Adobe" */
412 emit_byte(cinfo, 0x64);
413 emit_byte(cinfo, 0x6F);
414 emit_byte(cinfo, 0x62);
415 emit_byte(cinfo, 0x65);
416 emit_2bytes(cinfo, 100); /* Version */
417 emit_2bytes(cinfo, 0); /* Flags0 */
418 emit_2bytes(cinfo, 0); /* Flags1 */
419 switch (cinfo->jpeg_color_space) {
420 case JCS_YCbCr:
421 emit_byte(cinfo, 1); /* Color transform = 1 */
422 break;
423 case JCS_YCCK:
424 emit_byte(cinfo, 2); /* Color transform = 2 */
425 break;
426 default:
427 emit_byte(cinfo, 0); /* Color transform = 0 */
428 break;
429 }
430}
431
432
433/*
434 * These routines allow writing an arbitrary marker with parameters.
435 * The only intended use is to emit COM or APPn markers after calling
436 * write_file_header and before calling write_frame_header.
437 * Other uses are not guaranteed to produce desirable results.
438 * Counting the parameter bytes properly is the caller's responsibility.
439 */
440
441METHODDEF(void)static void
442write_marker_header (j_compress_ptr cinfo, int marker, unsigned int datalen)
443/* Emit an arbitrary marker header */
444{
445 if (datalen > (unsigned int) 65533) /* safety check */
446 ERREXIT(cinfo, JERR_BAD_LENGTH)((cinfo)->err->msg_code = (JERR_BAD_LENGTH), (*(cinfo)->
err->error_exit) ((j_common_ptr) (cinfo)));
447
448 emit_marker(cinfo, (JPEG_MARKER) marker);
449
450 emit_2bytes(cinfo, (int) (datalen + 2)); /* total length */
451}
452
453METHODDEF(void)static void
454write_marker_byte (j_compress_ptr cinfo, int val)
455/* Emit one byte of marker parameters following write_marker_header */
456{
457 emit_byte(cinfo, val);
458}
459
460
461/*
462 * Write datastream header.
463 * This consists of an SOI and optional APPn markers.
464 * We recommend use of the JFIF marker, but not the Adobe marker,
465 * when using YCbCr or grayscale data. The JFIF marker should NOT
466 * be used for any other JPEG colorspace. The Adobe marker is helpful
467 * to distinguish RGB, CMYK, and YCCK colorspaces.
468 * Note that an application can write additional header markers after
469 * jpeg_start_compress returns.
470 */
471
472METHODDEF(void)static void
473write_file_header (j_compress_ptr cinfo)
474{
475 my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
476
477 emit_marker(cinfo, M_SOI); /* first the SOI */
478
479 /* SOI is defined to reset restart interval to 0 */
480 marker->last_restart_interval = 0;
481
482 if (cinfo->write_JFIF_header) /* next an optional JFIF APP0 */
483 emit_jfif_app0(cinfo);
484 if (cinfo->write_Adobe_marker) /* next an optional Adobe APP14 */
485 emit_adobe_app14(cinfo);
486}
487
488
489/*
490 * Write frame header.
491 * This consists of DQT and SOFn markers.
492 * Note that we do not emit the SOF until we have emitted the DQT(s).
493 * This avoids compatibility problems with incorrect implementations that
494 * try to error-check the quant table numbers as soon as they see the SOF.
495 */
496
497METHODDEF(void)static void
498write_frame_header (j_compress_ptr cinfo)
499{
500 int ci, prec;
501 boolean is_baseline;
502 jpeg_component_info *compptr;
503
504 /* Emit DQT for each quantization table.
505 * Note that emit_dqt() suppresses any duplicate tables.
506 */
507 prec = 0;
508 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
509 ci++, compptr++) {
510 prec += emit_dqt(cinfo, compptr->quant_tbl_no);
511 }
512 /* now prec is nonzero iff there are any 16-bit quant tables. */
513
514 /* Check for a non-baseline specification.
515 * Note we assume that Huffman table numbers won't be changed later.
516 */
517 if (cinfo->arith_code || cinfo->progressive_mode ||
518 cinfo->data_precision != 8) {
519 is_baseline = FALSE0;
520 } else {
521 is_baseline = TRUE1;
522 for (ci = 0, compptr = cinfo->comp_info; ci < cinfo->num_components;
523 ci++, compptr++) {
524 if (compptr->dc_tbl_no > 1 || compptr->ac_tbl_no > 1)
525 is_baseline = FALSE0;
526 }
527 if (prec && is_baseline) {
528 is_baseline = FALSE0;
529 /* If it's baseline except for quantizer size, warn the user */
530 TRACEMS(cinfo, 0, JTRC_16BIT_TABLES)((cinfo)->err->msg_code = (JTRC_16BIT_TABLES), (*(cinfo
)->err->emit_message) ((j_common_ptr) (cinfo), (0)));
531 }
532 }
533
534 /* Emit the proper SOF marker */
535 if (cinfo->arith_code) {
536 emit_sof(cinfo, M_SOF9); /* SOF code for arithmetic coding */
537 } else {
538 if (cinfo->progressive_mode)
539 emit_sof(cinfo, M_SOF2); /* SOF code for progressive Huffman */
540 else if (is_baseline)
541 emit_sof(cinfo, M_SOF0); /* SOF code for baseline implementation */
542 else
543 emit_sof(cinfo, M_SOF1); /* SOF code for non-baseline Huffman file */
544 }
545}
546
547
548/*
549 * Write scan header.
550 * This consists of DHT or DAC markers, optional DRI, and SOS.
551 * Compressed data will be written following the SOS.
552 */
553
554METHODDEF(void)static void
555write_scan_header (j_compress_ptr cinfo)
556{
557 my_marker_ptr marker = (my_marker_ptr) cinfo->marker;
558 int i;
559 jpeg_component_info *compptr;
560
561 if (cinfo->arith_code) {
562 /* Emit arith conditioning info. We may have some duplication
563 * if the file has multiple scans, but it's so small it's hardly
564 * worth worrying about.
565 */
566 emit_dac(cinfo);
567 } else {
568 /* Emit Huffman tables.
569 * Note that emit_dht() suppresses any duplicate tables.
570 */
571 for (i = 0; i < cinfo->comps_in_scan; i++) {
572 compptr = cinfo->cur_comp_info[i];
573 if (cinfo->progressive_mode) {
574 /* Progressive mode: only DC or only AC tables are used in one scan */
575 if (cinfo->Ss == 0) {
576 if (cinfo->Ah == 0) /* DC needs no table for refinement scan */
577 emit_dht(cinfo, compptr->dc_tbl_no, FALSE0);
578 } else {
579 emit_dht(cinfo, compptr->ac_tbl_no, TRUE1);
580 }
581 } else {
582 /* Sequential mode: need both DC and AC tables */
583 emit_dht(cinfo, compptr->dc_tbl_no, FALSE0);
584 emit_dht(cinfo, compptr->ac_tbl_no, TRUE1);
585 }
586 }
587 }
588
589 /* Emit DRI if required --- note that DRI value could change for each scan.
590 * We avoid wasting space with unnecessary DRIs, however.
591 */
592 if (cinfo->restart_interval != marker->last_restart_interval) {
593 emit_dri(cinfo);
594 marker->last_restart_interval = cinfo->restart_interval;
595 }
596
597 emit_sos(cinfo);
598}
599
600
601/*
602 * Write datastream trailer.
603 */
604
605METHODDEF(void)static void
606write_file_trailer (j_compress_ptr cinfo)
607{
608 emit_marker(cinfo, M_EOI);
609}
610
611
612/*
613 * Write an abbreviated table-specification datastream.
614 * This consists of SOI, DQT and DHT tables, and EOI.
615 * Any table that is defined and not marked sent_table = TRUE will be
616 * emitted. Note that all tables will be marked sent_table = TRUE at exit.
617 */
618
619METHODDEF(void)static void
620write_tables_only (j_compress_ptr cinfo)
621{
622 int i;
623
624 emit_marker(cinfo, M_SOI);
625
626 /* Emit DQT for each quantization table.
627 * Only emit those tables that are actually associated with image components,
628 * if there are any image components, which will usually not be the case.
629 * Note that emit_dqt() suppresses any duplicate tables.
630 */
631 if (cinfo->num_components > 0) {
1
Assuming field 'num_components' is > 0
→
2
←
Taking true branch
→
632 int ci;
633 jpeg_component_info *compptr;
634 for (ci = 0, compptr = cinfo->comp_info; ci
2.1
'ci' is < field 'num_components'
 < cinfo->num_components;
3
←
Loop condition is true. Entering loop body
→
635 ci++, compptr++) {
636 (void) emit_dqt(cinfo, compptr->quant_tbl_no);
4
←
Calling 'emit_dqt'
→
637 }
638 } else {
639 for (i = 0; i < NUM_QUANT_TBLS4; i++) {
640 if (cinfo->quant_tbl_ptrs[i] != NULL((void*)0))
641 (void) emit_dqt(cinfo, i);
642 }
643 }
644
645 if (! cinfo->arith_code) {
646 for (i = 0; i < NUM_HUFF_TBLS4; i++) {
647 if (cinfo->dc_huff_tbl_ptrs[i] != NULL((void*)0))
648 emit_dht(cinfo, i, FALSE0);
649 if (cinfo->ac_huff_tbl_ptrs[i] != NULL((void*)0))
650 emit_dht(cinfo, i, TRUE1);
651 }
652 }
653
654 emit_marker(cinfo, M_EOI);
655}
656
657
658/*
659 * Initialize the marker writer module.
660 */
661
662GLOBAL(void)void
663jinit_marker_writerjIMWriter (j_compress_ptr cinfo)
664{
665 my_marker_ptr marker;
666
667 /* Create the subobject */
668 marker = (my_marker_ptr)
669 (*cinfo->mem->alloc_small) ((j_common_ptr) cinfo, JPOOL_IMAGE1,
670 SIZEOF(my_marker_writer)((size_t) sizeof(my_marker_writer)));
671 cinfo->marker = (struct jpeg_marker_writer *) marker;
672 /* Initialize method pointers */
673 marker->pub.write_file_header = write_file_header;
674 marker->pub.write_frame_header = write_frame_header;
675 marker->pub.write_scan_header = write_scan_header;
676 marker->pub.write_file_trailer = write_file_trailer;
677 marker->pub.write_tables_only = write_tables_only;
678 marker->pub.write_marker_header = write_marker_header;
679 marker->pub.write_marker_byte = write_marker_byte;
680 /* Initialize private state */
681 marker->last_restart_interval = 0;
682}