Problem report #110: base/src/emacs/src/coding.c (decode_coding_utf_8); UNINIT

[Dan Nicolaescu <dann@ics.uci.edu>]

CID: 110
Checker: UNINIT (help)
File: base/src/emacs/src/coding.c
Function: decode_coding_utf_8
Description: Using uninitialized value "consumed_chars_base"

Event var_decl: Declared variable "consumed_chars_base" without initializer
Also see events: [uninit_use]

1329 	  int consumed_chars = 0, consumed_chars_base;
1330 	  int multibytep = coding->src_multibyte;
1331 	  enum utf_bom_type bom = CODING_UTF_8_BOM (coding);
1332 	  Lisp_Object attr, charset_list;

At conditional (1): "((0), (((0), ((Vcoding_system_hash_table & -8)->key_and_value & -8))->contents[((2 * (coding)->id) + 1)] & -8))->contents[2] == Qdos" taking true path

1333 	  int eol_crlf = EQ (CODING_ID_EOL_TYPE (coding->id), Qdos);
1334 	  int byte_after_cr = -1;
1335 	

At conditional (2): "0" taking false path

1336 	  CODING_GET_INFO (coding, attr, charset_list);
1337 	

At conditional (3): "bom != 1" taking true path

1338 	  if (bom != utf_without_bom)
1339 	    {
1340 	      int c1, c2, c3;
1341 	
1342 	      src_base = src;

At conditional (4): "src == src_end" taking true path
At conditional (5): "src_base < src" taking true path

1343 	      ONE_MORE_BYTE (c1);
1344 	      if (! UTF_8_3_OCTET_LEADING_P (c1))
1345 		src = src_base;
1346 	      else
1347 		{
1348 		  ONE_MORE_BYTE (c2);      
1349 		  if (! UTF_8_EXTRA_OCTET_P (c2))
1350 		    src = src_base;
1351 		  else
1352 		    {
1353 		      ONE_MORE_BYTE (c3);      
1354 		      if (! UTF_8_EXTRA_OCTET_P (c3))
1355 			src = src_base;
1356 		      else
1357 			{
1358 			  if ((c1 != UTF_8_BOM_1)
1359 			      || (c2 != UTF_8_BOM_2) || (c3 != UTF_8_BOM_3))
1360 			    src = src_base;
1361 			  else
1362 			    CODING_UTF_8_BOM (coding) = utf_without_bom;
1363 			}
1364 		    }
1365 		}
1366 	    }
1367 	  CODING_UTF_8_BOM (coding) = utf_without_bom;
1368 	
1369 	
1370 	
1371 	  while (1)
1372 	    {
1373 	      int c, c1, c2, c3, c4, c5;
1374 	
1375 	      src_base = src;
1376 	      consumed_chars_base = consumed_chars;
1377 	
1378 	      if (charbuf >= charbuf_end)
1379 		break;
1380 	
1381 	      if (byte_after_cr >= 0)
1382 		c1 = byte_after_cr, byte_after_cr = -1;
1383 	      else
1384 		ONE_MORE_BYTE (c1);
1385 	      if (c1 < 0)
1386 		{
1387 		  c = - c1;
1388 		}
1389 	      else if (UTF_8_1_OCTET_P(c1))
1390 		{
1391 		  if (eol_crlf && c1 == '\r')
1392 		    ONE_MORE_BYTE (byte_after_cr);
1393 		  c = c1;
1394 		}
1395 	      else
1396 		{
1397 		  ONE_MORE_BYTE (c2);
1398 		  if (c2 < 0 || ! UTF_8_EXTRA_OCTET_P (c2))
1399 		    goto invalid_code;
1400 		  if (UTF_8_2_OCTET_LEADING_P (c1))
1401 		    {
1402 		      c = ((c1 & 0x1F) << 6) | (c2 & 0x3F);
1403 		      /* Reject overlong sequences here and below.  Encoders
1404 			 producing them are incorrect, they can be misleading,
1405 			 and they mess up read/write invariance.  */
1406 		      if (c < 128)
1407 			goto invalid_code;
1408 		    }
1409 		  else
1410 		    {
1411 		      ONE_MORE_BYTE (c3);
1412 		      if (c3 < 0 || ! UTF_8_EXTRA_OCTET_P (c3))
1413 			goto invalid_code;
1414 		      if (UTF_8_3_OCTET_LEADING_P (c1))
1415 			{
1416 			  c = (((c1 & 0xF) << 12)
1417 			       | ((c2 & 0x3F) << 6) | (c3 & 0x3F));
1418 			  if (c < 0x800
1419 			      || (c >= 0xd800 && c < 0xe000)) /* surrogates (invalid) */
1420 			    goto invalid_code;
1421 			}
1422 		      else
1423 			{
1424 			  ONE_MORE_BYTE (c4);
1425 			  if (c4 < 0 || ! UTF_8_EXTRA_OCTET_P (c4))
1426 			    goto invalid_code;
1427 			  if (UTF_8_4_OCTET_LEADING_P (c1))
1428 			    {
1429 			    c = (((c1 & 0x7) << 18) | ((c2 & 0x3F) << 12)
1430 				 | ((c3 & 0x3F) << 6) | (c4 & 0x3F));
1431 			    if (c < 0x10000)
1432 			      goto invalid_code;
1433 			    }
1434 			  else
1435 			    {
1436 			      ONE_MORE_BYTE (c5);
1437 			      if (c5 < 0 || ! UTF_8_EXTRA_OCTET_P (c5))
1438 				goto invalid_code;
1439 			      if (UTF_8_5_OCTET_LEADING_P (c1))
1440 				{
1441 				  c = (((c1 & 0x3) << 24) | ((c2 & 0x3F) << 18)
1442 				       | ((c3 & 0x3F) << 12) | ((c4 & 0x3F) << 6)
1443 				       | (c5 & 0x3F));
1444 				  if ((c > MAX_CHAR) || (c < 0x200000))
1445 				    goto invalid_code;
1446 				}
1447 			      else
1448 				goto invalid_code;
1449 			    }
1450 			}
1451 		    }
1452 		}
1453 	
1454 	      *charbuf++ = c;
1455 	      continue;
1456 	
1457 	    invalid_code:
1458 	      src = src_base;
1459 	      consumed_chars = consumed_chars_base;
1460 	      ONE_MORE_BYTE (c);
1461 	      *charbuf++ = ASCII_BYTE_P (c) ? c : BYTE8_TO_CHAR (c);
1462 	      coding->errors++;
1463 	    }
1464 	
1465 	 no_more_source:

Event uninit_use: Using uninitialized value "consumed_chars_base"
Also see events: [var_decl]

1466 	  coding->consumed_char += consumed_chars_base;
1467 	  coding->consumed = src_base - coding->source;
1468 	  coding->charbuf_used = charbuf - coding->charbuf;