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pngwutil.c.gcov
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pngwutil.c.gcov
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-: 0:Source:pngwutil.c
-: 0:Programs:15
-: 1:
-: 2:/* pngwutil.c - utilities to write a PNG file
-: 3: *
-: 4: * Last changed in libpng 1.6.32 [August 24, 2017]
-: 5: * Copyright (c) 1998-2002,2004,2006-2017 Glenn Randers-Pehrson
-: 6: * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger)
-: 7: * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.)
-: 8: *
-: 9: * This code is released under the libpng license.
-: 10: * For conditions of distribution and use, see the disclaimer
-: 11: * and license in png.h
-: 12: */
-: 13:
-: 14:#include "pngpriv.h"
-: 15:
-: 16:#ifdef PNG_WRITE_SUPPORTED
-: 17:
-: 18:#ifdef PNG_WRITE_INT_FUNCTIONS_SUPPORTED
-: 19:/* Place a 32-bit number into a buffer in PNG byte order. We work
-: 20: * with unsigned numbers for convenience, although one supported
-: 21: * ancillary chunk uses signed (two's complement) numbers.
-: 22: */
-: 23:void PNGAPI
306: 24:png_save_uint_32(png_bytep buf, png_uint_32 i)
-: 25:{
306: 26: buf[0] = (png_byte)((i >> 24) & 0xffU);
306: 27: buf[1] = (png_byte)((i >> 16) & 0xffU);
306: 28: buf[2] = (png_byte)((i >> 8) & 0xffU);
306: 29: buf[3] = (png_byte)( i & 0xffU);
306: 30:}
-: 31:
-: 32:/* Place a 16-bit number into a buffer in PNG byte order.
-: 33: * The parameter is declared unsigned int, not png_uint_16,
-: 34: * just to avoid potential problems on pre-ANSI C compilers.
-: 35: */
-: 36:void PNGAPI
9: 37:png_save_uint_16(png_bytep buf, unsigned int i)
-: 38:{
9: 39: buf[0] = (png_byte)((i >> 8) & 0xffU);
9: 40: buf[1] = (png_byte)( i & 0xffU);
9: 41:}
-: 42:#endif
-: 43:
-: 44:/* Simple function to write the signature. If we have already written
-: 45: * the magic bytes of the signature, or more likely, the PNG stream is
-: 46: * being embedded into another stream and doesn't need its own signature,
-: 47: * we should call png_set_sig_bytes() to tell libpng how many of the
-: 48: * bytes have already been written.
-: 49: */
-: 50:void PNGAPI
3: 51:png_write_sig(png_structrp png_ptr)
-: 52:{
3: 53: png_byte png_signature[8] = {137, 80, 78, 71, 13, 10, 26, 10};
-: 54:
-: 55:#ifdef PNG_IO_STATE_SUPPORTED
-: 56: /* Inform the I/O callback that the signature is being written */
3: 57: png_ptr->io_state = PNG_IO_WRITING | PNG_IO_SIGNATURE;
-: 58:#endif
-: 59:
-: 60: /* Write the rest of the 8 byte signature */
3: 61: png_write_data(png_ptr, &png_signature[png_ptr->sig_bytes],
3: 62: (png_size_t)(8 - png_ptr->sig_bytes));
-: 63:
3: 64: if (png_ptr->sig_bytes < 3)
3: 65: png_ptr->mode |= PNG_HAVE_PNG_SIGNATURE;
3: 66:}
-: 67:
-: 68:/* Write the start of a PNG chunk. The type is the chunk type.
-: 69: * The total_length is the sum of the lengths of all the data you will be
-: 70: * passing in png_write_chunk_data().
-: 71: */
-: 72:static void
87: 73:png_write_chunk_header(png_structrp png_ptr, png_uint_32 chunk_name,
-: 74: png_uint_32 length)
-: 75:{
-: 76: png_byte buf[8];
-: 77:
-: 78:#if defined(PNG_DEBUG) && (PNG_DEBUG > 0)
-: 79: PNG_CSTRING_FROM_CHUNK(buf, chunk_name);
-: 80: png_debug2(0, "Writing %s chunk, length = %lu", buf, (unsigned long)length);
-: 81:#endif
-: 82:
87: 83: if (png_ptr == NULL)
#####: 84: return;
-: 85:
-: 86:#ifdef PNG_IO_STATE_SUPPORTED
-: 87: /* Inform the I/O callback that the chunk header is being written.
-: 88: * PNG_IO_CHUNK_HDR requires a single I/O call.
-: 89: */
87: 90: png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_HDR;
-: 91:#endif
-: 92:
-: 93: /* Write the length and the chunk name */
87: 94: png_save_uint_32(buf, length);
87: 95: png_save_uint_32(buf + 4, chunk_name);
87: 96: png_write_data(png_ptr, buf, 8);
-: 97:
-: 98: /* Put the chunk name into png_ptr->chunk_name */
87: 99: png_ptr->chunk_name = chunk_name;
-: 100:
-: 101: /* Reset the crc and run it over the chunk name */
87: 102: png_reset_crc(png_ptr);
-: 103:
87: 104: png_calculate_crc(png_ptr, buf + 4, 4);
-: 105:
-: 106:#ifdef PNG_IO_STATE_SUPPORTED
-: 107: /* Inform the I/O callback that chunk data will (possibly) be written.
-: 108: * PNG_IO_CHUNK_DATA does NOT require a specific number of I/O calls.
-: 109: */
87: 110: png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_DATA;
-: 111:#endif
-: 112:}
-: 113:
-: 114:void PNGAPI
#####: 115:png_write_chunk_start(png_structrp png_ptr, png_const_bytep chunk_string,
-: 116: png_uint_32 length)
-: 117:{
#####: 118: png_write_chunk_header(png_ptr, PNG_CHUNK_FROM_STRING(chunk_string), length);
#####: 119:}
-: 120:
-: 121:/* Write the data of a PNG chunk started with png_write_chunk_header().
-: 122: * Note that multiple calls to this function are allowed, and that the
-: 123: * sum of the lengths from these calls *must* add up to the total_length
-: 124: * given to png_write_chunk_header().
-: 125: */
-: 126:void PNGAPI
120: 127:png_write_chunk_data(png_structrp png_ptr, png_const_bytep data,
-: 128: png_size_t length)
-: 129:{
-: 130: /* Write the data, and run the CRC over it */
120: 131: if (png_ptr == NULL)
#####: 132: return;
-: 133:
120: 134: if (data != NULL && length > 0)
-: 135: {
117: 136: png_write_data(png_ptr, data, length);
-: 137:
-: 138: /* Update the CRC after writing the data,
-: 139: * in case the user I/O routine alters it.
-: 140: */
117: 141: png_calculate_crc(png_ptr, data, length);
-: 142: }
-: 143:}
-: 144:
-: 145:/* Finish a chunk started with png_write_chunk_header(). */
-: 146:void PNGAPI
87: 147:png_write_chunk_end(png_structrp png_ptr)
-: 148:{
-: 149: png_byte buf[4];
-: 150:
87: 151: if (png_ptr == NULL) return;
-: 152:
-: 153:#ifdef PNG_IO_STATE_SUPPORTED
-: 154: /* Inform the I/O callback that the chunk CRC is being written.
-: 155: * PNG_IO_CHUNK_CRC requires a single I/O function call.
-: 156: */
87: 157: png_ptr->io_state = PNG_IO_WRITING | PNG_IO_CHUNK_CRC;
-: 158:#endif
-: 159:
-: 160: /* Write the crc in a single operation */
87: 161: png_save_uint_32(buf, png_ptr->crc);
-: 162:
87: 163: png_write_data(png_ptr, buf, (png_size_t)4);
-: 164:}
-: 165:
-: 166:/* Write a PNG chunk all at once. The type is an array of ASCII characters
-: 167: * representing the chunk name. The array must be at least 4 bytes in
-: 168: * length, and does not need to be null terminated. To be safe, pass the
-: 169: * pre-defined chunk names here, and if you need a new one, define it
-: 170: * where the others are defined. The length is the length of the data.
-: 171: * All the data must be present. If that is not possible, use the
-: 172: * png_write_chunk_start(), png_write_chunk_data(), and png_write_chunk_end()
-: 173: * functions instead.
-: 174: */
-: 175:static void
54: 176:png_write_complete_chunk(png_structrp png_ptr, png_uint_32 chunk_name,
-: 177: png_const_bytep data, png_size_t length)
-: 178:{
54: 179: if (png_ptr == NULL)
#####: 180: return;
-: 181:
-: 182: /* On 64-bit architectures 'length' may not fit in a png_uint_32. */
54: 183: if (length > PNG_UINT_31_MAX)
#####: 184: png_error(png_ptr, "length exceeds PNG maximum");
-: 185:
54: 186: png_write_chunk_header(png_ptr, chunk_name, (png_uint_32)length);
54: 187: png_write_chunk_data(png_ptr, data, length);
54: 188: png_write_chunk_end(png_ptr);
-: 189:}
-: 190:
-: 191:/* This is the API that calls the internal function above. */
-: 192:void PNGAPI
3: 193:png_write_chunk(png_structrp png_ptr, png_const_bytep chunk_string,
-: 194: png_const_bytep data, png_size_t length)
-: 195:{
3: 196: png_write_complete_chunk(png_ptr, PNG_CHUNK_FROM_STRING(chunk_string), data,
-: 197: length);
3: 198:}
-: 199:
-: 200:/* This is used below to find the size of an image to pass to png_deflate_claim,
-: 201: * so it only needs to be accurate if the size is less than 16384 bytes (the
-: 202: * point at which a lower LZ window size can be used.)
-: 203: */
-: 204:static png_alloc_size_t
6: 205:png_image_size(png_structrp png_ptr)
-: 206:{
-: 207: /* Only return sizes up to the maximum of a png_uint_32; do this by limiting
-: 208: * the width and height used to 15 bits.
-: 209: */
6: 210: png_uint_32 h = png_ptr->height;
-: 211:
6: 212: if (png_ptr->rowbytes < 32768 && h < 32768)
-: 213: {
6: 214: if (png_ptr->interlaced != 0)
-: 215: {
-: 216: /* Interlacing makes the image larger because of the replication of
-: 217: * both the filter byte and the padding to a byte boundary.
-: 218: */
#####: 219: png_uint_32 w = png_ptr->width;
#####: 220: unsigned int pd = png_ptr->pixel_depth;
-: 221: png_alloc_size_t cb_base;
-: 222: int pass;
-: 223:
#####: 224: for (cb_base=0, pass=0; pass<=6; ++pass)
-: 225: {
#####: 226: png_uint_32 pw = PNG_PASS_COLS(w, pass);
-: 227:
#####: 228: if (pw > 0)
#####: 229: cb_base += (PNG_ROWBYTES(pd, pw)+1) * PNG_PASS_ROWS(h, pass);
-: 230: }
-: 231:
#####: 232: return cb_base;
-: 233: }
-: 234:
-: 235: else
6: 236: return (png_ptr->rowbytes+1) * h;
-: 237: }
-: 238:
-: 239: else
#####: 240: return 0xffffffffU;
-: 241:}
-: 242:
-: 243:#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-: 244: /* This is the code to hack the first two bytes of the deflate stream (the
-: 245: * deflate header) to correct the windowBits value to match the actual data
-: 246: * size. Note that the second argument is the *uncompressed* size but the
-: 247: * first argument is the *compressed* data (and it must be deflate
-: 248: * compressed.)
-: 249: */
-: 250:static void
36: 251:optimize_cmf(png_bytep data, png_alloc_size_t data_size)
-: 252:{
-: 253: /* Optimize the CMF field in the zlib stream. The resultant zlib stream is
-: 254: * still compliant to the stream specification.
-: 255: */
36: 256: if (data_size <= 16384) /* else windowBits must be 15 */
-: 257: {
33: 258: unsigned int z_cmf = data[0]; /* zlib compression method and flags */
-: 259:
33: 260: if ((z_cmf & 0x0f) == 8 && (z_cmf & 0xf0) <= 0x70)
-: 261: {
-: 262: unsigned int z_cinfo;
-: 263: unsigned int half_z_window_size;
-: 264:
33: 265: z_cinfo = z_cmf >> 4;
33: 266: half_z_window_size = 1U << (z_cinfo + 7);
-: 267:
33: 268: if (data_size <= half_z_window_size) /* else no change */
-: 269: {
-: 270: unsigned int tmp;
-: 271:
-: 272: do
-: 273: {
33: 274: half_z_window_size >>= 1;
33: 275: --z_cinfo;
-: 276: }
33: 277: while (z_cinfo > 0 && data_size <= half_z_window_size);
-: 278:
33: 279: z_cmf = (z_cmf & 0x0f) | (z_cinfo << 4);
-: 280:
33: 281: data[0] = (png_byte)z_cmf;
33: 282: tmp = data[1] & 0xe0;
33: 283: tmp += 0x1f - ((z_cmf << 8) + tmp) % 0x1f;
33: 284: data[1] = (png_byte)tmp;
-: 285: }
-: 286: }
-: 287: }
36: 288:}
-: 289:#endif /* WRITE_OPTIMIZE_CMF */
-: 290:
-: 291:/* Initialize the compressor for the appropriate type of compression. */
-: 292:static int
36: 293:png_deflate_claim(png_structrp png_ptr, png_uint_32 owner,
-: 294: png_alloc_size_t data_size)
-: 295:{
36: 296: if (png_ptr->zowner != 0)
-: 297: {
-: 298:#if defined(PNG_WARNINGS_SUPPORTED) || defined(PNG_ERROR_TEXT_SUPPORTED)
-: 299: char msg[64];
-: 300:
#####: 301: PNG_STRING_FROM_CHUNK(msg, owner);
#####: 302: msg[4] = ':';
#####: 303: msg[5] = ' ';
#####: 304: PNG_STRING_FROM_CHUNK(msg+6, png_ptr->zowner);
-: 305: /* So the message that results is "<chunk> using zstream"; this is an
-: 306: * internal error, but is very useful for debugging. i18n requirements
-: 307: * are minimal.
-: 308: */
#####: 309: (void)png_safecat(msg, (sizeof msg), 10, " using zstream");
-: 310:#endif
-: 311:#if PNG_RELEASE_BUILD
#####: 312: png_warning(png_ptr, msg);
-: 313:
-: 314: /* Attempt sane error recovery */
#####: 315: if (png_ptr->zowner == png_IDAT) /* don't steal from IDAT */
-: 316: {
#####: 317: png_ptr->zstream.msg = PNGZ_MSG_CAST("in use by IDAT");
#####: 318: return Z_STREAM_ERROR;
-: 319: }
-: 320:
#####: 321: png_ptr->zowner = 0;
-: 322:#else
-: 323: png_error(png_ptr, msg);
-: 324:#endif
-: 325: }
-: 326:
-: 327: {
36: 328: int level = png_ptr->zlib_level;
36: 329: int method = png_ptr->zlib_method;
36: 330: int windowBits = png_ptr->zlib_window_bits;
36: 331: int memLevel = png_ptr->zlib_mem_level;
-: 332: int strategy; /* set below */
-: 333: int ret; /* zlib return code */
-: 334:
36: 335: if (owner == png_IDAT)
-: 336: {
3: 337: if ((png_ptr->flags & PNG_FLAG_ZLIB_CUSTOM_STRATEGY) != 0)
#####: 338: strategy = png_ptr->zlib_strategy;
-: 339:
3: 340: else if (png_ptr->do_filter != PNG_FILTER_NONE)
3: 341: strategy = PNG_Z_DEFAULT_STRATEGY;
-: 342:
-: 343: else
#####: 344: strategy = PNG_Z_DEFAULT_NOFILTER_STRATEGY;
-: 345: }
-: 346:
-: 347: else
-: 348: {
-: 349:#ifdef PNG_WRITE_CUSTOMIZE_ZTXT_COMPRESSION_SUPPORTED
33: 350: level = png_ptr->zlib_text_level;
33: 351: method = png_ptr->zlib_text_method;
33: 352: windowBits = png_ptr->zlib_text_window_bits;
33: 353: memLevel = png_ptr->zlib_text_mem_level;
33: 354: strategy = png_ptr->zlib_text_strategy;
-: 355:#else
-: 356: /* If customization is not supported the values all come from the
-: 357: * IDAT values except for the strategy, which is fixed to the
-: 358: * default. (This is the pre-1.6.0 behavior too, although it was
-: 359: * implemented in a very different way.)
-: 360: */
-: 361: strategy = Z_DEFAULT_STRATEGY;
-: 362:#endif
-: 363: }
-: 364:
-: 365: /* Adjust 'windowBits' down if larger than 'data_size'; to stop this
-: 366: * happening just pass 32768 as the data_size parameter. Notice that zlib
-: 367: * requires an extra 262 bytes in the window in addition to the data to be
-: 368: * able to see the whole of the data, so if data_size+262 takes us to the
-: 369: * next windowBits size we need to fix up the value later. (Because even
-: 370: * though deflate needs the extra window, inflate does not!)
-: 371: */
36: 372: if (data_size <= 16384)
-: 373: {
-: 374: /* IMPLEMENTATION NOTE: this 'half_window_size' stuff is only here to
-: 375: * work round a Microsoft Visual C misbehavior which, contrary to C-90,
-: 376: * widens the result of the following shift to 64-bits if (and,
-: 377: * apparently, only if) it is used in a test.
-: 378: */
33: 379: unsigned int half_window_size = 1U << (windowBits-1);
-: 380:
264: 381: while (data_size + 262 <= half_window_size)
-: 382: {
198: 383: half_window_size >>= 1;
198: 384: --windowBits;
-: 385: }
-: 386: }
-: 387:
-: 388: /* Check against the previous initialized values, if any. */
69: 389: if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0 &&
33: 390: (png_ptr->zlib_set_level != level ||
#####: 391: png_ptr->zlib_set_method != method ||
#####: 392: png_ptr->zlib_set_window_bits != windowBits ||
#####: 393: png_ptr->zlib_set_mem_level != memLevel ||
#####: 394: png_ptr->zlib_set_strategy != strategy))
-: 395: {
33: 396: if (deflateEnd(&png_ptr->zstream) != Z_OK)
#####: 397: png_warning(png_ptr, "deflateEnd failed (ignored)");
-: 398:
33: 399: png_ptr->flags &= ~PNG_FLAG_ZSTREAM_INITIALIZED;
-: 400: }
-: 401:
-: 402: /* For safety clear out the input and output pointers (currently zlib
-: 403: * doesn't use them on Init, but it might in the future).
-: 404: */
36: 405: png_ptr->zstream.next_in = NULL;
36: 406: png_ptr->zstream.avail_in = 0;
36: 407: png_ptr->zstream.next_out = NULL;
36: 408: png_ptr->zstream.avail_out = 0;
-: 409:
-: 410: /* Now initialize if required, setting the new parameters, otherwise just
-: 411: * do a simple reset to the previous parameters.
-: 412: */
36: 413: if ((png_ptr->flags & PNG_FLAG_ZSTREAM_INITIALIZED) != 0)
#####: 414: ret = deflateReset(&png_ptr->zstream);
-: 415:
-: 416: else
-: 417: {
36: 418: ret = deflateInit2(&png_ptr->zstream, level, method, windowBits,
-: 419: memLevel, strategy);
-: 420:
36: 421: if (ret == Z_OK)
36: 422: png_ptr->flags |= PNG_FLAG_ZSTREAM_INITIALIZED;
-: 423: }
-: 424:
-: 425: /* The return code is from either deflateReset or deflateInit2; they have
-: 426: * pretty much the same set of error codes.
-: 427: */
36: 428: if (ret == Z_OK)
36: 429: png_ptr->zowner = owner;
-: 430:
-: 431: else
#####: 432: png_zstream_error(png_ptr, ret);
-: 433:
36: 434: return ret;
-: 435: }
-: 436:}
-: 437:
-: 438:/* Clean up (or trim) a linked list of compression buffers. */
-: 439:void /* PRIVATE */
3: 440:png_free_buffer_list(png_structrp png_ptr, png_compression_bufferp *listp)
-: 441:{
3: 442: png_compression_bufferp list = *listp;
-: 443:
3: 444: if (list != NULL)
-: 445: {
3: 446: *listp = NULL;
-: 447:
-: 448: do
-: 449: {
3: 450: png_compression_bufferp next = list->next;
-: 451:
3: 452: png_free(png_ptr, list);
3: 453: list = next;
-: 454: }
3: 455: while (list != NULL);
-: 456: }
3: 457:}
-: 458:
-: 459:#ifdef PNG_WRITE_COMPRESSED_TEXT_SUPPORTED
-: 460:/* This pair of functions encapsulates the operation of (a) compressing a
-: 461: * text string, and (b) issuing it later as a series of chunk data writes.
-: 462: * The compression_state structure is shared context for these functions
-: 463: * set up by the caller to allow access to the relevant local variables.
-: 464: *
-: 465: * compression_buffer (new in 1.6.0) is just a linked list of zbuffer_size
-: 466: * temporary buffers. From 1.6.0 it is retained in png_struct so that it will
-: 467: * be correctly freed in the event of a write error (previous implementations
-: 468: * just leaked memory.)
-: 469: */
-: 470:typedef struct
-: 471:{
-: 472: png_const_bytep input; /* The uncompressed input data */
-: 473: png_alloc_size_t input_len; /* Its length */
-: 474: png_uint_32 output_len; /* Final compressed length */
-: 475: png_byte output[1024]; /* First block of output */
-: 476:} compression_state;
-: 477:
-: 478:static void
33: 479:png_text_compress_init(compression_state *comp, png_const_bytep input,
-: 480: png_alloc_size_t input_len)
-: 481:{
33: 482: comp->input = input;
33: 483: comp->input_len = input_len;
33: 484: comp->output_len = 0;
33: 485:}
-: 486:
-: 487:/* Compress the data in the compression state input */
-: 488:static int
33: 489:png_text_compress(png_structrp png_ptr, png_uint_32 chunk_name,
-: 490: compression_state *comp, png_uint_32 prefix_len)
-: 491:{
-: 492: int ret;
-: 493:
-: 494: /* To find the length of the output it is necessary to first compress the
-: 495: * input. The result is buffered rather than using the two-pass algorithm
-: 496: * that is used on the inflate side; deflate is assumed to be slower and a
-: 497: * PNG writer is assumed to have more memory available than a PNG reader.
-: 498: *
-: 499: * IMPLEMENTATION NOTE: the zlib API deflateBound() can be used to find an
-: 500: * upper limit on the output size, but it is always bigger than the input
-: 501: * size so it is likely to be more efficient to use this linked-list
-: 502: * approach.
-: 503: */
33: 504: ret = png_deflate_claim(png_ptr, chunk_name, comp->input_len);
-: 505:
33: 506: if (ret != Z_OK)
#####: 507: return ret;
-: 508:
-: 509: /* Set up the compression buffers, we need a loop here to avoid overflowing a
-: 510: * uInt. Use ZLIB_IO_MAX to limit the input. The output is always limited
-: 511: * by the output buffer size, so there is no need to check that. Since this
-: 512: * is ANSI-C we know that an 'int', hence a uInt, is always at least 16 bits
-: 513: * in size.
-: 514: */
-: 515: {
33: 516: png_compression_bufferp *end = &png_ptr->zbuffer_list;
33: 517: png_alloc_size_t input_len = comp->input_len; /* may be zero! */
-: 518: png_uint_32 output_len;
-: 519:
-: 520: /* zlib updates these for us: */
33: 521: png_ptr->zstream.next_in = PNGZ_INPUT_CAST(comp->input);
33: 522: png_ptr->zstream.avail_in = 0; /* Set below */
33: 523: png_ptr->zstream.next_out = comp->output;
33: 524: png_ptr->zstream.avail_out = (sizeof comp->output);
-: 525:
33: 526: output_len = png_ptr->zstream.avail_out;
-: 527:
-: 528: do
-: 529: {
33: 530: uInt avail_in = ZLIB_IO_MAX;
-: 531:
33: 532: if (avail_in > input_len)
33: 533: avail_in = (uInt)input_len;
-: 534:
33: 535: input_len -= avail_in;
-: 536:
33: 537: png_ptr->zstream.avail_in = avail_in;
-: 538:
33: 539: if (png_ptr->zstream.avail_out == 0)
-: 540: {
-: 541: png_compression_buffer *next;
-: 542:
-: 543: /* Chunk data is limited to 2^31 bytes in length, so the prefix
-: 544: * length must be counted here.
-: 545: */
#####: 546: if (output_len + prefix_len > PNG_UINT_31_MAX)
-: 547: {
#####: 548: ret = Z_MEM_ERROR;
#####: 549: break;
-: 550: }
-: 551:
-: 552: /* Need a new (malloc'ed) buffer, but there may be one present
-: 553: * already.
-: 554: */
#####: 555: next = *end;
#####: 556: if (next == NULL)
-: 557: {
#####: 558: next = png_voidcast(png_compression_bufferp, png_malloc_base
-: 559: (png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
-: 560:
#####: 561: if (next == NULL)
-: 562: {
#####: 563: ret = Z_MEM_ERROR;
#####: 564: break;
-: 565: }
-: 566:
-: 567: /* Link in this buffer (so that it will be freed later) */
#####: 568: next->next = NULL;
#####: 569: *end = next;
-: 570: }
-: 571:
#####: 572: png_ptr->zstream.next_out = next->output;
#####: 573: png_ptr->zstream.avail_out = png_ptr->zbuffer_size;
#####: 574: output_len += png_ptr->zstream.avail_out;
-: 575:
-: 576: /* Move 'end' to the next buffer pointer. */
#####: 577: end = &next->next;
-: 578: }
-: 579:
-: 580: /* Compress the data */
33: 581: ret = deflate(&png_ptr->zstream,
-: 582: input_len > 0 ? Z_NO_FLUSH : Z_FINISH);
-: 583:
-: 584: /* Claw back input data that was not consumed (because avail_in is
-: 585: * reset above every time round the loop).
-: 586: */
33: 587: input_len += png_ptr->zstream.avail_in;
33: 588: png_ptr->zstream.avail_in = 0; /* safety */
-: 589: }
33: 590: while (ret == Z_OK);
-: 591:
-: 592: /* There may be some space left in the last output buffer. This needs to
-: 593: * be subtracted from output_len.
-: 594: */
33: 595: output_len -= png_ptr->zstream.avail_out;
33: 596: png_ptr->zstream.avail_out = 0; /* safety */
33: 597: comp->output_len = output_len;
-: 598:
-: 599: /* Now double check the output length, put in a custom message if it is
-: 600: * too long. Otherwise ensure the z_stream::msg pointer is set to
-: 601: * something.
-: 602: */
33: 603: if (output_len + prefix_len >= PNG_UINT_31_MAX)
-: 604: {
#####: 605: png_ptr->zstream.msg = PNGZ_MSG_CAST("compressed data too long");
#####: 606: ret = Z_MEM_ERROR;
-: 607: }
-: 608:
-: 609: else
33: 610: png_zstream_error(png_ptr, ret);
-: 611:
-: 612: /* Reset zlib for another zTXt/iTXt or image data */
33: 613: png_ptr->zowner = 0;
-: 614:
-: 615: /* The only success case is Z_STREAM_END, input_len must be 0; if not this
-: 616: * is an internal error.
-: 617: */
33: 618: if (ret == Z_STREAM_END && input_len == 0)
-: 619: {
-: 620:#ifdef PNG_WRITE_OPTIMIZE_CMF_SUPPORTED
-: 621: /* Fix up the deflate header, if required */
33: 622: optimize_cmf(comp->output, comp->input_len);
-: 623:#endif
-: 624: /* But Z_OK is returned, not Z_STREAM_END; this allows the claim
-: 625: * function above to return Z_STREAM_END on an error (though it never
-: 626: * does in the current versions of zlib.)
-: 627: */
33: 628: return Z_OK;
-: 629: }
-: 630:
-: 631: else
#####: 632: return ret;
-: 633: }
-: 634:}
-: 635:
-: 636:/* Ship the compressed text out via chunk writes */
-: 637:static void
33: 638:png_write_compressed_data_out(png_structrp png_ptr, compression_state *comp)
-: 639:{
33: 640: png_uint_32 output_len = comp->output_len;
33: 641: png_const_bytep output = comp->output;
33: 642: png_uint_32 avail = (sizeof comp->output);
33: 643: png_compression_buffer *next = png_ptr->zbuffer_list;
-: 644:
-: 645: for (;;)
-: 646: {
33: 647: if (avail > output_len)
33: 648: avail = output_len;
-: 649:
33: 650: png_write_chunk_data(png_ptr, output, avail);
-: 651:
33: 652: output_len -= avail;
-: 653:
33: 654: if (output_len == 0 || next == NULL)
-: 655: break;
-: 656:
#####: 657: avail = png_ptr->zbuffer_size;
#####: 658: output = next->output;
#####: 659: next = next->next;
#####: 660: }
-: 661:
-: 662: /* This is an internal error; 'next' must have been NULL! */
33: 663: if (output_len > 0)
#####: 664: png_error(png_ptr, "error writing ancillary chunked compressed data");
33: 665:}
-: 666:#endif /* WRITE_COMPRESSED_TEXT */
-: 667:
-: 668:/* Write the IHDR chunk, and update the png_struct with the necessary
-: 669: * information. Note that the rest of this code depends upon this
-: 670: * information being correct.
-: 671: */
-: 672:void /* PRIVATE */
3: 673:png_write_IHDR(png_structrp png_ptr, png_uint_32 width, png_uint_32 height,
-: 674: int bit_depth, int color_type, int compression_type, int filter_type,
-: 675: int interlace_type)
-: 676:{
-: 677: png_byte buf[13]; /* Buffer to store the IHDR info */
-: 678: int is_invalid_depth;
-: 679:
-: 680: png_debug(1, "in png_write_IHDR");
-: 681:
-: 682: /* Check that we have valid input data from the application info */
3: 683: switch (color_type)
-: 684: {
-: 685: case PNG_COLOR_TYPE_GRAY:
#####: 686: switch (bit_depth)
-: 687: {
-: 688: case 1:
-: 689: case 2:
-: 690: case 4:
-: 691: case 8:
-: 692:#ifdef PNG_WRITE_16BIT_SUPPORTED
-: 693: case 16:
-: 694:#endif
#####: 695: png_ptr->channels = 1; break;
-: 696:
-: 697: default:
#####: 698: png_error(png_ptr,
-: 699: "Invalid bit depth for grayscale image");
-: 700: }
#####: 701: break;
-: 702:
-: 703: case PNG_COLOR_TYPE_RGB:
#####: 704: is_invalid_depth = (bit_depth != 8);
-: 705:#ifdef PNG_WRITE_16BIT_SUPPORTED
#####: 706: is_invalid_depth = (is_invalid_depth && bit_depth != 16);
-: 707:#endif
#####: 708: if (is_invalid_depth)
#####: 709: png_error(png_ptr, "Invalid bit depth for RGB image");
-: 710:
#####: 711: png_ptr->channels = 3;
#####: 712: break;
-: 713:
-: 714: case PNG_COLOR_TYPE_PALETTE:
#####: 715: switch (bit_depth)
-: 716: {
-: 717: case 1:
-: 718: case 2:
-: 719: case 4:
-: 720: case 8:
#####: 721: png_ptr->channels = 1;
#####: 722: break;
-: 723:
-: 724: default:
#####: 725: png_error(png_ptr, "Invalid bit depth for paletted image");
-: 726: }
#####: 727: break;
-: 728:
-: 729: case PNG_COLOR_TYPE_GRAY_ALPHA:
#####: 730: is_invalid_depth = (bit_depth != 8);
-: 731:#ifdef PNG_WRITE_16BIT_SUPPORTED
#####: 732: is_invalid_depth = (is_invalid_depth && bit_depth != 16);
-: 733:#endif
#####: 734: if (is_invalid_depth)
#####: 735: png_error(png_ptr, "Invalid bit depth for grayscale+alpha image");
-: 736:
#####: 737: png_ptr->channels = 2;
#####: 738: break;
-: 739:
-: 740: case PNG_COLOR_TYPE_RGB_ALPHA:
3: 741: is_invalid_depth = (bit_depth != 8);
-: 742:#ifdef PNG_WRITE_16BIT_SUPPORTED
3: 743: is_invalid_depth = (is_invalid_depth && bit_depth != 16);
-: 744:#endif
3: 745: if (is_invalid_depth)
#####: 746: png_error(png_ptr, "Invalid bit depth for RGBA image");
-: 747:
3: 748: png_ptr->channels = 4;
3: 749: break;
-: 750:
-: 751: default:
#####: 752: png_error(png_ptr, "Invalid image color type specified");
-: 753: }
-: 754:
3: 755: if (compression_type != PNG_COMPRESSION_TYPE_BASE)
-: 756: {
#####: 757: png_warning(png_ptr, "Invalid compression type specified");
#####: 758: compression_type = PNG_COMPRESSION_TYPE_BASE;
-: 759: }
-: 760:
-: 761: /* Write filter_method 64 (intrapixel differencing) only if
-: 762: * 1. Libpng was compiled with PNG_MNG_FEATURES_SUPPORTED and
-: 763: * 2. Libpng did not write a PNG signature (this filter_method is only
-: 764: * used in PNG datastreams that are embedded in MNG datastreams) and
-: 765: * 3. The application called png_permit_mng_features with a mask that
-: 766: * included PNG_FLAG_MNG_FILTER_64 and
-: 767: * 4. The filter_method is 64 and
-: 768: * 5. The color_type is RGB or RGBA
-: 769: */
3: 770: if (
-: 771:#ifdef PNG_MNG_FEATURES_SUPPORTED
3: 772: !((png_ptr->mng_features_permitted & PNG_FLAG_MNG_FILTER_64) != 0 &&
#####: 773: ((png_ptr->mode & PNG_HAVE_PNG_SIGNATURE) == 0) &&
#####: 774: (color_type == PNG_COLOR_TYPE_RGB ||
-: 775: color_type == PNG_COLOR_TYPE_RGB_ALPHA) &&
3: 776: (filter_type == PNG_INTRAPIXEL_DIFFERENCING)) &&
-: 777:#endif
-: 778: filter_type != PNG_FILTER_TYPE_BASE)
-: 779: {
#####: 780: png_warning(png_ptr, "Invalid filter type specified");
#####: 781: filter_type = PNG_FILTER_TYPE_BASE;
-: 782: }
-: 783:
-: 784:#ifdef PNG_WRITE_INTERLACING_SUPPORTED
3: 785: if (interlace_type != PNG_INTERLACE_NONE &&
-: 786: interlace_type != PNG_INTERLACE_ADAM7)
-: 787: {
#####: 788: png_warning(png_ptr, "Invalid interlace type specified");
#####: 789: interlace_type = PNG_INTERLACE_ADAM7;
-: 790: }
-: 791:#else
-: 792: interlace_type=PNG_INTERLACE_NONE;
-: 793:#endif
-: 794:
-: 795: /* Save the relevant information */
3: 796: png_ptr->bit_depth = (png_byte)bit_depth;
3: 797: png_ptr->color_type = (png_byte)color_type;
3: 798: png_ptr->interlaced = (png_byte)interlace_type;
-: 799:#ifdef PNG_MNG_FEATURES_SUPPORTED
3: 800: png_ptr->filter_type = (png_byte)filter_type;
-: 801:#endif
3: 802: png_ptr->compression_type = (png_byte)compression_type;
3: 803: png_ptr->width = width;
3: 804: png_ptr->height = height;
-: 805:
3: 806: png_ptr->pixel_depth = (png_byte)(bit_depth * png_ptr->channels);
3: 807: png_ptr->rowbytes = PNG_ROWBYTES(png_ptr->pixel_depth, width);
-: 808: /* Set the usr info, so any transformations can modify it */
3: 809: png_ptr->usr_width = png_ptr->width;
3: 810: png_ptr->usr_bit_depth = png_ptr->bit_depth;
3: 811: png_ptr->usr_channels = png_ptr->channels;
-: 812:
-: 813: /* Pack the header information into the buffer */
3: 814: png_save_uint_32(buf, width);
3: 815: png_save_uint_32(buf + 4, height);
3: 816: buf[8] = (png_byte)bit_depth;
3: 817: buf[9] = (png_byte)color_type;
3: 818: buf[10] = (png_byte)compression_type;
3: 819: buf[11] = (png_byte)filter_type;
3: 820: buf[12] = (png_byte)interlace_type;
-: 821:
-: 822: /* Write the chunk */
3: 823: png_write_complete_chunk(png_ptr, png_IHDR, buf, (png_size_t)13);
-: 824:
3: 825: if ((png_ptr->do_filter) == PNG_NO_FILTERS)
-: 826: {
6: 827: if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE ||
3: 828: png_ptr->bit_depth < 8)
#####: 829: png_ptr->do_filter = PNG_FILTER_NONE;
-: 830:
-: 831: else
3: 832: png_ptr->do_filter = PNG_ALL_FILTERS;
-: 833: }
-: 834:
3: 835: png_ptr->mode = PNG_HAVE_IHDR; /* not READY_FOR_ZTXT */
3: 836:}
-: 837:
-: 838:/* Write the palette. We are careful not to trust png_color to be in the
-: 839: * correct order for PNG, so people can redefine it to any convenient
-: 840: * structure.
-: 841: */
-: 842:void /* PRIVATE */
#####: 843:png_write_PLTE(png_structrp png_ptr, png_const_colorp palette,
-: 844: png_uint_32 num_pal)
-: 845:{
-: 846: png_uint_32 max_palette_length, i;
-: 847: png_const_colorp pal_ptr;
-: 848: png_byte buf[3];
-: 849:
-: 850: png_debug(1, "in png_write_PLTE");
-: 851:
#####: 852: max_palette_length = (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ?
#####: 853: (1 << png_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH;
-: 854:
#####: 855: if ((
-: 856:#ifdef PNG_MNG_FEATURES_SUPPORTED
#####: 857: (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 &&
-: 858:#endif
#####: 859: num_pal == 0) || num_pal > max_palette_length)
-: 860: {
#####: 861: if (png_ptr->color_type == PNG_COLOR_TYPE_PALETTE)
-: 862: {
#####: 863: png_error(png_ptr, "Invalid number of colors in palette");
-: 864: }
-: 865:
-: 866: else
-: 867: {
#####: 868: png_warning(png_ptr, "Invalid number of colors in palette");
#####: 869: return;
-: 870: }
-: 871: }
-: 872:
#####: 873: if ((png_ptr->color_type & PNG_COLOR_MASK_COLOR) == 0)
-: 874: {
#####: 875: png_warning(png_ptr,
-: 876: "Ignoring request to write a PLTE chunk in grayscale PNG");
-: 877:
#####: 878: return;
-: 879: }
-: 880:
#####: 881: png_ptr->num_palette = (png_uint_16)num_pal;
-: 882: png_debug1(3, "num_palette = %d", png_ptr->num_palette);
-: 883:
#####: 884: png_write_chunk_header(png_ptr, png_PLTE, (png_uint_32)(num_pal * 3));
-: 885:#ifdef PNG_POINTER_INDEXING_SUPPORTED
-: 886:
#####: 887: for (i = 0, pal_ptr = palette; i < num_pal; i++, pal_ptr++)
-: 888: {
#####: 889: buf[0] = pal_ptr->red;
#####: 890: buf[1] = pal_ptr->green;
#####: 891: buf[2] = pal_ptr->blue;
#####: 892: png_write_chunk_data(png_ptr, buf, (png_size_t)3);
-: 893: }
-: 894:
-: 895:#else
-: 896: /* This is a little slower but some buggy compilers need to do this
-: 897: * instead
-: 898: */
-: 899: pal_ptr=palette;
-: 900:
-: 901: for (i = 0; i < num_pal; i++)
-: 902: {
-: 903: buf[0] = pal_ptr[i].red;
-: 904: buf[1] = pal_ptr[i].green;
-: 905: buf[2] = pal_ptr[i].blue;
-: 906: png_write_chunk_data(png_ptr, buf, (png_size_t)3);
-: 907: }
-: 908:
-: 909:#endif
#####: 910: png_write_chunk_end(png_ptr);
#####: 911: png_ptr->mode |= PNG_HAVE_PLTE;
-: 912:}
-: 913:
-: 914:/* This is similar to png_text_compress, above, except that it does not require
-: 915: * all of the data at once and, instead of buffering the compressed result,
-: 916: * writes it as IDAT chunks. Unlike png_text_compress it *can* png_error out
-: 917: * because it calls the write interface. As a result it does its own error
-: 918: * reporting and does not return an error code. In the event of error it will
-: 919: * just call png_error. The input data length may exceed 32-bits. The 'flush'
-: 920: * parameter is exactly the same as that to deflate, with the following
-: 921: * meanings:
-: 922: *
-: 923: * Z_NO_FLUSH: normal incremental output of compressed data
-: 924: * Z_SYNC_FLUSH: do a SYNC_FLUSH, used by png_write_flush
-: 925: * Z_FINISH: this is the end of the input, do a Z_FINISH and clean up
-: 926: *
-: 927: * The routine manages the acquire and release of the png_ptr->zstream by
-: 928: * checking and (at the end) clearing png_ptr->zowner; it does some sanity
-: 929: * checks on the 'mode' flags while doing this.
-: 930: */
-: 931:void /* PRIVATE */
753: 932:png_compress_IDAT(png_structrp png_ptr, png_const_bytep input,
-: 933: png_alloc_size_t input_len, int flush)
-: 934:{
753: 935: if (png_ptr->zowner != png_IDAT)
-: 936: {
-: 937: /* First time. Ensure we have a temporary buffer for compression and
-: 938: * trim the buffer list if it has more than one entry to free memory.
-: 939: * If 'WRITE_COMPRESSED_TEXT' is not set the list will never have been
-: 940: * created at this point, but the check here is quick and safe.
-: 941: */
3: 942: if (png_ptr->zbuffer_list == NULL)
-: 943: {
3: 944: png_ptr->zbuffer_list = png_voidcast(png_compression_bufferp,
-: 945: png_malloc(png_ptr, PNG_COMPRESSION_BUFFER_SIZE(png_ptr)));
3: 946: png_ptr->zbuffer_list->next = NULL;
-: 947: }
-: 948:
-: 949: else
#####: 950: png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list->next);
-: 951:
-: 952: /* It is a terminal error if we can't claim the zstream. */
3: 953: if (png_deflate_claim(png_ptr, png_IDAT, png_image_size(png_ptr)) != Z_OK)
#####: 954: png_error(png_ptr, png_ptr->zstream.msg);
-: 955:
-: 956: /* The output state is maintained in png_ptr->zstream, so it must be
-: 957: * initialized here after the claim.
-: 958: */
3: 959: png_ptr->zstream.next_out = png_ptr->zbuffer_list->output;
3: 960: png_ptr->zstream.avail_out = png_ptr->zbuffer_size;
-: 961: }
-: 962:
-: 963: /* Now loop reading and writing until all the input is consumed or an error
-: 964: * terminates the operation. The _out values are maintained across calls to
-: 965: * this function, but the input must be reset each time.
-: 966: */
753: 967: png_ptr->zstream.next_in = PNGZ_INPUT_CAST(input);
753: 968: png_ptr->zstream.avail_in = 0; /* set below */
-: 969: for (;;)
-: 970: {
-: 971: int ret;
-: 972:
-: 973: /* INPUT: from the row data */
768: 974: uInt avail = ZLIB_IO_MAX;
-: 975:
768: 976: if (avail > input_len)
768: 977: avail = (uInt)input_len; /* safe because of the check */
-: 978:
768: 979: png_ptr->zstream.avail_in = avail;
768: 980: input_len -= avail;
-: 981:
768: 982: ret = deflate(&png_ptr->zstream, input_len > 0 ? Z_NO_FLUSH : flush);
-: 983:
-: 984: /* Include as-yet unconsumed input */
768: 985: input_len += png_ptr->zstream.avail_in;
768: 986: png_ptr->zstream.avail_in = 0;
-: 987:
-: 988: /* OUTPUT: write complete IDAT chunks when avail_out drops to zero. Note
-: 989: * that these two zstream fields are preserved across the calls, therefore
-: 990: * there is no need to set these up on entry to the loop.
-: 991: */
768: 992: if (png_ptr->zstream.avail_out == 0)
-: 993: {
27: 994: png_bytep data = png_ptr->zbuffer_list->output;
27: 995: uInt size = png_ptr->zbuffer_size;
-: 996:
-: 997: /* Write an IDAT containing the data then reset the buffer. The
-: 998: * first IDAT may need deflate header optimization.