ucnv_lmb.c revision b13da9df870a61b11249bf741347908dbea0edd8
1/* 2********************************************************************** 3* Copyright (C) 2000-2006, International Business Machines 4* Corporation and others. All Rights Reserved. 5********************************************************************** 6* file name: ucnv_lmb.cpp 7* encoding: US-ASCII 8* tab size: 4 (not used) 9* indentation:4 10* 11* created on: 2000feb09 12* created by: Brendan Murray 13* extensively hacked up by: Jim Snyder-Grant 14* 15* Modification History: 16* 17* Date Name Description 18* 19* 06/20/2000 helena OS/400 port changes; mostly typecast. 20* 06/27/2000 Jim Snyder-Grant Deal with partial characters and small buffers. 21* Add comments to document LMBCS format and implementation 22* restructured order & breakdown of functions 23* 06/28/2000 helena Major rewrite for the callback API changes. 24*/ 25 26#include "unicode/utypes.h" 27 28#if !UCONFIG_NO_CONVERSION && !UCONFIG_NO_LEGACY_CONVERSION 29 30#include "unicode/ucnv_err.h" 31#include "unicode/ucnv.h" 32#include "unicode/uset.h" 33#include "cmemory.h" 34#include "cstring.h" 35#include "uassert.h" 36#include "ucnv_imp.h" 37#include "ucnv_bld.h" 38#include "ucnv_cnv.h" 39 40#define LENGTHOF(array) (int32_t)(sizeof(array)/sizeof((array)[0])) 41 42/* 43 LMBCS 44 45 (Lotus Multi-Byte Character Set) 46 47 LMBCS was invented in the late 1980's and is primarily used in Lotus Notes 48 databases and in Lotus 1-2-3 files. Programmers who work with the APIs 49 into these products will sometimes need to deal with strings in this format. 50 51 The code in this file provides an implementation for an ICU converter of 52 LMBCS to and from Unicode. 53 54 Since the LMBCS character set is only sparsely documented in existing 55 printed or online material, we have added extensive annotation to this 56 file to serve as a guide to understanding LMBCS. 57 58 LMBCS was originally designed with these four sometimes-competing design goals: 59 60 -Provide encodings for the characters in 12 existing national standards 61 (plus a few other characters) 62 -Minimal memory footprint 63 -Maximal speed of conversion into the existing national character sets 64 -No need to track a changing state as you interpret a string. 65 66 67 All of the national character sets LMBCS was trying to encode are 'ANSI' 68 based, in that the bytes from 0x20 - 0x7F are almost exactly the 69 same common Latin unaccented characters and symbols in all character sets. 70 71 So, in order to help meet the speed & memory design goals, the common ANSI 72 bytes from 0x20-0x7F are represented by the same single-byte values in LMBCS. 73 74 The general LMBCS code unit is from 1-3 bytes. We can describe the 3 bytes as 75 follows: 76 77 [G] D1 [D2] 78 79 That is, a sometimes-optional 'group' byte, followed by 1 and sometimes 2 80 data bytes. The maximum size of a LMBCS chjaracter is 3 bytes: 81*/ 82#define ULMBCS_CHARSIZE_MAX 3 83/* 84 The single-byte values from 0x20 to 0x7F are examples of single D1 bytes. 85 We often have to figure out if byte values are below or above this, so we 86 use the ANSI nomenclature 'C0' and 'C1' to refer to the range of control 87 characters just above & below the common lower-ANSI range */ 88#define ULMBCS_C0END 0x1F 89#define ULMBCS_C1START 0x80 90/* 91 Since LMBCS is always dealing in byte units. we create a local type here for 92 dealing with these units of LMBCS code units: 93 94*/ 95typedef uint8_t ulmbcs_byte_t; 96 97/* 98 Most of the values less than 0x20 are reserved in LMBCS to announce 99 which national character standard is being used for the 'D' bytes. 100 In the comments we show the common name and the IBM character-set ID 101 for these character-set announcers: 102*/ 103 104#define ULMBCS_GRP_L1 0x01 /* Latin-1 :ibm-850 */ 105#define ULMBCS_GRP_GR 0x02 /* Greek :ibm-851 */ 106#define ULMBCS_GRP_HE 0x03 /* Hebrew :ibm-1255 */ 107#define ULMBCS_GRP_AR 0x04 /* Arabic :ibm-1256 */ 108#define ULMBCS_GRP_RU 0x05 /* Cyrillic :ibm-1251 */ 109#define ULMBCS_GRP_L2 0x06 /* Latin-2 :ibm-852 */ 110#define ULMBCS_GRP_TR 0x08 /* Turkish :ibm-1254 */ 111#define ULMBCS_GRP_TH 0x0B /* Thai :ibm-874 */ 112#define ULMBCS_GRP_JA 0x10 /* Japanese :ibm-943 */ 113#define ULMBCS_GRP_KO 0x11 /* Korean :ibm-1261 */ 114#define ULMBCS_GRP_TW 0x12 /* Chinese SC :ibm-950 */ 115#define ULMBCS_GRP_CN 0x13 /* Chinese TC :ibm-1386 */ 116 117/* 118 So, the beginning of understanding LMBCS is that IF the first byte of a LMBCS 119 character is one of those 12 values, you can interpret the remaining bytes of 120 that character as coming from one of those character sets. Since the lower 121 ANSI bytes already are represented in single bytes, using one of the character 122 set announcers is used to announce a character that starts with a byte of 123 0x80 or greater. 124 125 The character sets are arranged so that the single byte sets all appear 126 before the multi-byte character sets. When we need to tell whether a 127 group byte is for a single byte char set or not we use this define: */ 128 129#define ULMBCS_DOUBLEOPTGROUP_START 0x10 130 131/* 132However, to fully understand LMBCS, you must also understand a series of 133exceptions & optimizations made in service of the design goals. 134 135First, those of you who are character set mavens may have noticed that 136the 'double-byte' character sets are actually multi-byte character sets 137that can have 1 or two bytes, even in the upper-ascii range. To force 138each group byte to introduce a fixed-width encoding (to make it faster to 139count characters), we use a convention of doubling up on the group byte 140to introduce any single-byte character > 0x80 in an otherwise double-byte 141character set. So, for example, the LMBCS sequence x10 x10 xAE is the 142same as '0xAE' in the Japanese code page 943. 143 144Next, you will notice that the list of group bytes has some gaps. 145These are used in various ways. 146 147We reserve a few special single byte values for common control 148characters. These are in the same place as their ANSI eqivalents for speed. 149*/ 150 151#define ULMBCS_HT 0x09 /* Fixed control char - Horizontal Tab */ 152#define ULMBCS_LF 0x0A /* Fixed control char - Line Feed */ 153#define ULMBCS_CR 0x0D /* Fixed control char - Carriage Return */ 154 155/* Then, 1-2-3 reserved a special single-byte character to put at the 156beginning of internal 'system' range names: */ 157 158#define ULMBCS_123SYSTEMRANGE 0x19 159 160/* Then we needed a place to put all the other ansi control characters 161that must be moved to different values because LMBCS reserves those 162values for other purposes. To represent the control characters, we start 163with a first byte of 0xF & add the control chaarcter value as the 164second byte */ 165#define ULMBCS_GRP_CTRL 0x0F 166 167/* For the C0 controls (less than 0x20), we add 0x20 to preserve the 168useful doctrine that any byte less than 0x20 in a LMBCS char must be 169the first byte of a character:*/ 170#define ULMBCS_CTRLOFFSET 0x20 171 172/* 173Where to put the characters that aren't part of any of the 12 national 174character sets? The first thing that was done, in the earlier years of 175LMBCS, was to use up the spaces of the form 176 177 [G] D1, 178 179 where 'G' was one of the single-byte character groups, and 180 D1 was less than 0x80. These sequences are gathered together 181 into a Lotus-invented doublebyte character set to represent a 182 lot of stray values. Internally, in this implementation, we track this 183 as group '0', as a place to tuck this exceptions list.*/ 184 185#define ULMBCS_GRP_EXCEPT 0x00 186/* 187 Finally, as the durability and usefulness of UNICODE became clear, 188 LOTUS added a new group 0x14 to hold Unicode values not otherwise 189 represented in LMBCS: */ 190#define ULMBCS_GRP_UNICODE 0x14 191/* The two bytes appearing after a 0x14 are intrepreted as UFT-16 BE 192(Big-Endian) characters. The exception comes when the UTF16 193representation would have a zero as the second byte. In that case, 194'F6' is used in its place, and the bytes are swapped. (This prevents 195LMBCS from encoding any Unicode values of the form U+F6xx, but that's OK: 1960xF6xx is in the middle of the Private Use Area.)*/ 197#define ULMBCS_UNICOMPATZERO 0xF6 198 199/* It is also useful in our code to have a constant for the size of 200a LMBCS char that holds a literal Unicode value */ 201#define ULMBCS_UNICODE_SIZE 3 202 203/* 204To squish the LMBCS representations down even further, and to make 205translations even faster,sometimes the optimization group byte can be dropped 206from a LMBCS character. This is decided on a process-by-process basis. The 207group byte that is dropped is called the 'optimization group'. 208 209For Notes, the optimzation group is always 0x1.*/ 210#define ULMBCS_DEFAULTOPTGROUP 0x1 211/* For 1-2-3 files, the optimzation group is stored in the header of the 1-2-3 212file. 213 214 In any case, when using ICU, you either pass in the 215optimization group as part of the name of the converter (LMBCS-1, LMBCS-2, 216etc.). Using plain 'LMBCS' as the name of the converter will give you 217LMBCS-1. 218 219 220*** Implementation strategy *** 221 222 223Because of the extensive use of other character sets, the LMBCS converter 224keeps a mapping between optimization groups and IBM character sets, so that 225ICU converters can be created and used as needed. */ 226 227/* As you can see, even though any byte below 0x20 could be an optimization 228byte, only those at 0x13 or below can map to an actual converter. To limit 229some loops and searches, we define a value for that last group converter:*/ 230 231#define ULMBCS_GRP_LAST 0x13 /* last LMBCS group that has a converter */ 232 233static const char * const OptGroupByteToCPName[ULMBCS_GRP_LAST + 1] = { 234 /* 0x0000 */ "lmb-excp", /* internal home for the LOTUS exceptions list */ 235 /* 0x0001 */ "ibm-850", 236 /* 0x0002 */ "ibm-851", 237 /* 0x0003 */ "windows-1255", 238 /* 0x0004 */ "windows-1256", 239 /* 0x0005 */ "windows-1251", 240 /* 0x0006 */ "ibm-852", 241 /* 0x0007 */ NULL, /* Unused */ 242 /* 0x0008 */ "windows-1254", 243 /* 0x0009 */ NULL, /* Control char HT */ 244 /* 0x000A */ NULL, /* Control char LF */ 245 /* 0x000B */ "windows-874", 246 /* 0x000C */ NULL, /* Unused */ 247 /* 0x000D */ NULL, /* Control char CR */ 248 /* 0x000E */ NULL, /* Unused */ 249 /* 0x000F */ NULL, /* Control chars: 0x0F20 + C0/C1 character: algorithmic */ 250 /* 0x0010 */ "windows-932", 251 /* 0x0011 */ "windows-949", 252 /* 0x0012 */ "windows-950", 253 /* 0x0013 */ "windows-936" 254 255 /* The rest are null, including the 0x0014 Unicode compatibility region 256 and 0x0019, the 1-2-3 system range control char */ 257}; 258 259 260/* That's approximately all the data that's needed for translating 261 LMBCS to Unicode. 262 263 264However, to translate Unicode to LMBCS, we need some more support. 265 266That's because there are often more than one possible mappings from a Unicode 267code point back into LMBCS. The first thing we do is look up into a table 268to figure out if there are more than one possible mappings. This table, 269arranged by Unicode values (including ranges) either lists which group 270to use, or says that it could go into one or more of the SBCS sets, or 271into one or more of the DBCS sets. (If the character exists in both DBCS & 272SBCS, the table will place it in the SBCS sets, to make the LMBCS code point 273length as small as possible. Here's the two special markers we use to indicate 274ambiguous mappings: */ 275 276#define ULMBCS_AMBIGUOUS_SBCS 0x80 /* could fit in more than one 277 LMBCS sbcs native encoding 278 (example: most accented latin) */ 279#define ULMBCS_AMBIGUOUS_MBCS 0x81 /* could fit in more than one 280 LMBCS mbcs native encoding 281 (example: Unihan) */ 282 283/* And here's a simple way to see if a group falls in an appropriate range */ 284#define ULMBCS_AMBIGUOUS_MATCH(agroup, xgroup) \ 285 ((((agroup) == ULMBCS_AMBIGUOUS_SBCS) && \ 286 (xgroup) < ULMBCS_DOUBLEOPTGROUP_START) || \ 287 (((agroup) == ULMBCS_AMBIGUOUS_MBCS) && \ 288 (xgroup) >= ULMBCS_DOUBLEOPTGROUP_START)) 289 290 291/* The table & some code to use it: */ 292 293 294static const struct _UniLMBCSGrpMap 295{ 296 const UChar uniStartRange; 297 const UChar uniEndRange; 298 const ulmbcs_byte_t GrpType; 299} UniLMBCSGrpMap[] 300= 301{ 302 303 {0x0001, 0x001F, ULMBCS_GRP_CTRL}, 304 {0x0080, 0x009F, ULMBCS_GRP_CTRL}, 305 {0x00A0, 0x01CD, ULMBCS_AMBIGUOUS_SBCS}, 306 {0x01CE, 0x01CE, ULMBCS_GRP_TW }, 307 {0x01CF, 0x02B9, ULMBCS_AMBIGUOUS_SBCS}, 308 {0x02BA, 0x02BA, ULMBCS_GRP_CN}, 309 {0x02BC, 0x02C8, ULMBCS_AMBIGUOUS_SBCS}, 310 {0x02C9, 0x02D0, ULMBCS_AMBIGUOUS_MBCS}, 311 {0x02D8, 0x02DD, ULMBCS_AMBIGUOUS_SBCS}, 312 {0x0384, 0x03CE, ULMBCS_AMBIGUOUS_SBCS}, 313 {0x0400, 0x044E, ULMBCS_GRP_RU}, 314 {0x044F, 0x044F, ULMBCS_AMBIGUOUS_MBCS}, 315 {0x0450, 0x0491, ULMBCS_GRP_RU}, 316 {0x05B0, 0x05F2, ULMBCS_GRP_HE}, 317 {0x060C, 0x06AF, ULMBCS_GRP_AR}, 318 {0x0E01, 0x0E5B, ULMBCS_GRP_TH}, 319 {0x200C, 0x200F, ULMBCS_AMBIGUOUS_SBCS}, 320 {0x2010, 0x2010, ULMBCS_AMBIGUOUS_MBCS}, 321 {0x2013, 0x2015, ULMBCS_AMBIGUOUS_SBCS}, 322 {0x2016, 0x2016, ULMBCS_AMBIGUOUS_MBCS}, 323 {0x2017, 0x2024, ULMBCS_AMBIGUOUS_SBCS}, 324 {0x2025, 0x2025, ULMBCS_AMBIGUOUS_MBCS}, 325 {0x2026, 0x2026, ULMBCS_AMBIGUOUS_SBCS}, 326 {0x2027, 0x2027, ULMBCS_GRP_CN}, 327 {0x2030, 0x2033, ULMBCS_AMBIGUOUS_SBCS}, 328 {0x2035, 0x2035, ULMBCS_AMBIGUOUS_MBCS}, 329 {0x2039, 0x203A, ULMBCS_AMBIGUOUS_SBCS}, 330 {0x203B, 0x203B, ULMBCS_AMBIGUOUS_MBCS}, 331 {0x2074, 0x2074, ULMBCS_GRP_KO}, 332 {0x207F, 0x207F, ULMBCS_GRP_EXCEPT}, 333 {0x2081, 0x2084, ULMBCS_GRP_KO}, 334 {0x20A4, 0x20AC, ULMBCS_AMBIGUOUS_SBCS}, 335 {0x2103, 0x2109, ULMBCS_AMBIGUOUS_MBCS}, 336 {0x2111, 0x2126, ULMBCS_AMBIGUOUS_SBCS}, 337 {0x212B, 0x212B, ULMBCS_AMBIGUOUS_MBCS}, 338 {0x2135, 0x2135, ULMBCS_AMBIGUOUS_SBCS}, 339 {0x2153, 0x2154, ULMBCS_GRP_KO}, 340 {0x215B, 0x215E, ULMBCS_GRP_EXCEPT}, 341 {0x2160, 0x2179, ULMBCS_AMBIGUOUS_MBCS}, 342 {0x2190, 0x2195, ULMBCS_GRP_EXCEPT}, 343 {0x2196, 0x2199, ULMBCS_AMBIGUOUS_MBCS}, 344 {0x21A8, 0x21A8, ULMBCS_GRP_EXCEPT}, 345 {0x21B8, 0x21B9, ULMBCS_GRP_CN}, 346 {0x21D0, 0x21D5, ULMBCS_GRP_EXCEPT}, 347 {0x21E7, 0x21E7, ULMBCS_GRP_CN}, 348 {0x2200, 0x220B, ULMBCS_GRP_EXCEPT}, 349 {0x220F, 0x2215, ULMBCS_AMBIGUOUS_MBCS}, 350 {0x2219, 0x2220, ULMBCS_GRP_EXCEPT}, 351 {0x2223, 0x2228, ULMBCS_AMBIGUOUS_MBCS}, 352 {0x2229, 0x222B, ULMBCS_GRP_EXCEPT}, 353 {0x222C, 0x223D, ULMBCS_AMBIGUOUS_MBCS}, 354 {0x2245, 0x2248, ULMBCS_GRP_EXCEPT}, 355 {0x224C, 0x224C, ULMBCS_GRP_TW}, 356 {0x2252, 0x2252, ULMBCS_AMBIGUOUS_MBCS}, 357 {0x2260, 0x2265, ULMBCS_GRP_EXCEPT}, 358 {0x2266, 0x226F, ULMBCS_AMBIGUOUS_MBCS}, 359 {0x2282, 0x2297, ULMBCS_GRP_EXCEPT}, 360 {0x2299, 0x22BF, ULMBCS_AMBIGUOUS_MBCS}, 361 {0x22C0, 0x22C0, ULMBCS_GRP_EXCEPT}, 362 {0x2310, 0x2310, ULMBCS_GRP_EXCEPT}, 363 {0x2312, 0x2312, ULMBCS_AMBIGUOUS_MBCS}, 364 {0x2318, 0x2321, ULMBCS_GRP_EXCEPT}, 365 {0x2318, 0x2321, ULMBCS_GRP_CN}, 366 {0x2460, 0x24E9, ULMBCS_AMBIGUOUS_MBCS}, 367 {0x2500, 0x2500, ULMBCS_AMBIGUOUS_SBCS}, 368 {0x2501, 0x2501, ULMBCS_AMBIGUOUS_MBCS}, 369 {0x2502, 0x2502, ULMBCS_AMBIGUOUS_SBCS}, 370 {0x2503, 0x2503, ULMBCS_AMBIGUOUS_MBCS}, 371 {0x2504, 0x2505, ULMBCS_GRP_TW}, 372 {0x2506, 0x2665, ULMBCS_AMBIGUOUS_MBCS}, 373 {0x2666, 0x2666, ULMBCS_GRP_EXCEPT}, 374 {0x2666, 0x2666, ULMBCS_GRP_EXCEPT}, 375 {0x2667, 0x2E7F, ULMBCS_AMBIGUOUS_SBCS}, 376 {0x2E80, 0xF861, ULMBCS_AMBIGUOUS_MBCS}, 377 {0xF862, 0xF8FF, ULMBCS_GRP_EXCEPT}, 378 {0xF900, 0xFA2D, ULMBCS_AMBIGUOUS_MBCS}, 379 {0xFB00, 0xFEFF, ULMBCS_AMBIGUOUS_SBCS}, 380 {0xFF01, 0xFFEE, ULMBCS_AMBIGUOUS_MBCS}, 381 {0xFFFF, 0xFFFF, ULMBCS_GRP_UNICODE} 382}; 383 384static ulmbcs_byte_t 385FindLMBCSUniRange(UChar uniChar) 386{ 387 const struct _UniLMBCSGrpMap * pTable = UniLMBCSGrpMap; 388 389 while (uniChar > pTable->uniEndRange) 390 { 391 pTable++; 392 } 393 394 if (uniChar >= pTable->uniStartRange) 395 { 396 return pTable->GrpType; 397 } 398 return ULMBCS_GRP_UNICODE; 399} 400 401/* 402We also ask the creator of a converter to send in a preferred locale 403that we can use in resolving ambiguous mappings. They send the locale 404in as a string, and we map it, if possible, to one of the 405LMBCS groups. We use this table, and the associated code, to 406do the lookup: */ 407 408/************************************************** 409 This table maps locale ID's to LMBCS opt groups. 410 The default return is group 0x01. Note that for 411 performance reasons, the table is sorted in 412 increasing alphabetic order, with the notable 413 exception of zhTW. This is to force the check 414 for Traditonal Chinese before dropping back to 415 Simplified. 416 417 Note too that the Latin-1 groups have been 418 commented out because it's the default, and 419 this shortens the table, allowing a serial 420 search to go quickly. 421 *************************************************/ 422 423static const struct _LocaleLMBCSGrpMap 424{ 425 const char *LocaleID; 426 const ulmbcs_byte_t OptGroup; 427} LocaleLMBCSGrpMap[] = 428{ 429 {"ar", ULMBCS_GRP_AR}, 430 {"be", ULMBCS_GRP_RU}, 431 {"bg", ULMBCS_GRP_L2}, 432 /* {"ca", ULMBCS_GRP_L1}, */ 433 {"cs", ULMBCS_GRP_L2}, 434 /* {"da", ULMBCS_GRP_L1}, */ 435 /* {"de", ULMBCS_GRP_L1}, */ 436 {"el", ULMBCS_GRP_GR}, 437 /* {"en", ULMBCS_GRP_L1}, */ 438 /* {"es", ULMBCS_GRP_L1}, */ 439 /* {"et", ULMBCS_GRP_L1}, */ 440 /* {"fi", ULMBCS_GRP_L1}, */ 441 /* {"fr", ULMBCS_GRP_L1}, */ 442 {"he", ULMBCS_GRP_HE}, 443 {"hu", ULMBCS_GRP_L2}, 444 /* {"is", ULMBCS_GRP_L1}, */ 445 /* {"it", ULMBCS_GRP_L1}, */ 446 {"iw", ULMBCS_GRP_HE}, 447 {"ja", ULMBCS_GRP_JA}, 448 {"ko", ULMBCS_GRP_KO}, 449 /* {"lt", ULMBCS_GRP_L1}, */ 450 /* {"lv", ULMBCS_GRP_L1}, */ 451 {"mk", ULMBCS_GRP_RU}, 452 /* {"nl", ULMBCS_GRP_L1}, */ 453 /* {"no", ULMBCS_GRP_L1}, */ 454 {"pl", ULMBCS_GRP_L2}, 455 /* {"pt", ULMBCS_GRP_L1}, */ 456 {"ro", ULMBCS_GRP_L2}, 457 {"ru", ULMBCS_GRP_RU}, 458 {"sh", ULMBCS_GRP_L2}, 459 {"sk", ULMBCS_GRP_L2}, 460 {"sl", ULMBCS_GRP_L2}, 461 {"sq", ULMBCS_GRP_L2}, 462 {"sr", ULMBCS_GRP_RU}, 463 /* {"sv", ULMBCS_GRP_L1}, */ 464 {"th", ULMBCS_GRP_TH}, 465 {"tr", ULMBCS_GRP_TR}, 466 {"uk", ULMBCS_GRP_RU}, 467 /* {"vi", ULMBCS_GRP_L1}, */ 468 {"zhTW", ULMBCS_GRP_TW}, 469 {"zh", ULMBCS_GRP_CN}, 470 {NULL, ULMBCS_GRP_L1} 471}; 472 473 474static ulmbcs_byte_t 475FindLMBCSLocale(const char *LocaleID) 476{ 477 const struct _LocaleLMBCSGrpMap *pTable = LocaleLMBCSGrpMap; 478 479 if ((!LocaleID) || (!*LocaleID)) 480 { 481 return 0; 482 } 483 484 while (pTable->LocaleID) 485 { 486 if (*pTable->LocaleID == *LocaleID) /* Check only first char for speed */ 487 { 488 /* First char matches - check whole name, for entry-length */ 489 if (uprv_strncmp(pTable->LocaleID, LocaleID, strlen(pTable->LocaleID)) == 0) 490 return pTable->OptGroup; 491 } 492 else 493 if (*pTable->LocaleID > *LocaleID) /* Sorted alphabetically - exit */ 494 break; 495 pTable++; 496 } 497 return ULMBCS_GRP_L1; 498} 499 500 501/* 502 Before we get to the main body of code, here's how we hook up to the rest 503 of ICU. ICU converters are required to define a structure that includes 504 some function pointers, and some common data, in the style of a C++ 505 vtable. There is also room in there for converter-specific data. LMBCS 506 uses that converter-specific data to keep track of the 12 subconverters 507 we use, the optimization group, and the group (if any) that matches the 508 locale. We have one structure instantiated for each of the 12 possible 509 optimization groups. To avoid typos & to avoid boring the reader, we 510 put the declarations of these structures and functions into macros. To see 511 the definitions of these structures, see unicode\ucnv_bld.h 512*/ 513 514typedef struct 515 { 516 UConverterSharedData *OptGrpConverter[ULMBCS_GRP_LAST+1]; /* Converter per Opt. grp. */ 517 uint8_t OptGroup; /* default Opt. grp. for this LMBCS session */ 518 uint8_t localeConverterIndex; /* reasonable locale match for index */ 519 } 520UConverterDataLMBCS; 521 522 523#define DECLARE_LMBCS_DATA(n) \ 524static const UConverterImpl _LMBCSImpl##n={\ 525 UCNV_LMBCS_##n,\ 526 NULL,NULL,\ 527 _LMBCSOpen##n,\ 528 _LMBCSClose,\ 529 NULL,\ 530 _LMBCSToUnicodeWithOffsets,\ 531 _LMBCSToUnicodeWithOffsets,\ 532 _LMBCSFromUnicode,\ 533 _LMBCSFromUnicode,\ 534 NULL,\ 535 NULL,\ 536 NULL,\ 537 NULL,\ 538 _LMBCSSafeClone,\ 539 _LMBCSGetUnicodeSet\ 540};\ 541static const UConverterStaticData _LMBCSStaticData##n={\ 542 sizeof(UConverterStaticData),\ 543 "LMBCS-" #n,\ 544 0, UCNV_IBM, UCNV_LMBCS_##n, 1, 3,\ 545 { 0x3f, 0, 0, 0 },1,FALSE,FALSE,0,0,{0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0} \ 546};\ 547const UConverterSharedData _LMBCSData##n={\ 548 sizeof(UConverterSharedData), ~((uint32_t) 0),\ 549 NULL, NULL, &_LMBCSStaticData##n, FALSE, &_LMBCSImpl##n, \ 550 0 \ 551}; 552 553 /* The only function we needed to duplicate 12 times was the 'open' 554function, which will do basically the same thing except set a different 555optimization group. So, we put the common stuff into a worker function, 556and set up another macro to stamp out the 12 open functions:*/ 557#define DEFINE_LMBCS_OPEN(n) \ 558static void \ 559 _LMBCSOpen##n(UConverter* _this,const char* name,const char* locale,uint32_t options,UErrorCode* err) \ 560{ _LMBCSOpenWorker(_this, name,locale,options, err, n);} 561 562 563 564/* Here's the open worker & the common close function */ 565static void 566_LMBCSOpenWorker(UConverter* _this, 567 const char* name, 568 const char* locale, 569 uint32_t options, 570 UErrorCode* err, 571 ulmbcs_byte_t OptGroup 572 ) 573{ 574 UConverterDataLMBCS * extraInfo = (UConverterDataLMBCS*)uprv_malloc (sizeof (UConverterDataLMBCS)); 575 if(extraInfo != NULL) 576 { 577 ulmbcs_byte_t i; 578 579 uprv_memset(extraInfo, 0, sizeof(UConverterDataLMBCS)); 580 581 for (i=0; i <= ULMBCS_GRP_LAST && U_SUCCESS(*err); i++) 582 { 583 if(OptGroupByteToCPName[i] != NULL) { 584 extraInfo->OptGrpConverter[i] = ucnv_loadSharedData(OptGroupByteToCPName[i], NULL, err); 585 } 586 } 587 588 if(U_SUCCESS(*err)) { 589 extraInfo->OptGroup = OptGroup; 590 extraInfo->localeConverterIndex = FindLMBCSLocale(locale); 591 } else { 592 /* one of the subconverters could not be loaded, unload the previous ones */ 593 while(i > 0) { 594 if(extraInfo->OptGrpConverter[--i] != NULL) { 595 ucnv_unloadSharedDataIfReady(extraInfo->OptGrpConverter[i]); 596 extraInfo->OptGrpConverter[i] = NULL; 597 } 598 } 599 } 600 } 601 else 602 { 603 *err = U_MEMORY_ALLOCATION_ERROR; 604 } 605 _this->extraInfo = extraInfo; 606} 607 608static void 609_LMBCSClose(UConverter * _this) 610{ 611 if (_this->extraInfo != NULL) 612 { 613 ulmbcs_byte_t Ix; 614 UConverterDataLMBCS * extraInfo = (UConverterDataLMBCS *) _this->extraInfo; 615 616 for (Ix=0; Ix <= ULMBCS_GRP_LAST; Ix++) 617 { 618 if (extraInfo->OptGrpConverter[Ix] != NULL) 619 ucnv_unloadSharedDataIfReady(extraInfo->OptGrpConverter[Ix]); 620 } 621 if (!_this->isExtraLocal) { 622 uprv_free (_this->extraInfo); 623 } 624 } 625} 626 627typedef struct LMBCSClone { 628 UConverter cnv; 629 UConverterDataLMBCS lmbcs; 630} LMBCSClone; 631 632static UConverter * 633_LMBCSSafeClone(const UConverter *cnv, 634 void *stackBuffer, 635 int32_t *pBufferSize, 636 UErrorCode *status) { 637 LMBCSClone *newLMBCS; 638 UConverterDataLMBCS *extraInfo; 639 int32_t i; 640 641 if(*pBufferSize<=0) { 642 *pBufferSize=(int32_t)sizeof(LMBCSClone); 643 return NULL; 644 } 645 646 extraInfo=(UConverterDataLMBCS *)cnv->extraInfo; 647 newLMBCS=(LMBCSClone *)stackBuffer; 648 649 /* ucnv.c/ucnv_safeClone() copied the main UConverter already */ 650 651 uprv_memcpy(&newLMBCS->lmbcs, extraInfo, sizeof(UConverterDataLMBCS)); 652 653 /* share the subconverters */ 654 for(i = 0; i <= ULMBCS_GRP_LAST; ++i) { 655 if(extraInfo->OptGrpConverter[i] != NULL) { 656 ucnv_incrementRefCount(extraInfo->OptGrpConverter[i]); 657 } 658 } 659 660 newLMBCS->cnv.extraInfo = &newLMBCS->lmbcs; 661 newLMBCS->cnv.isExtraLocal = TRUE; 662 return &newLMBCS->cnv; 663} 664 665static void 666_LMBCSGetUnicodeSet(const UConverter *cnv, 667 const USetAdder *sa, 668 UConverterUnicodeSet which, 669 UErrorCode *pErrorCode) { 670 /* all but U+F6xx, see LMBCS explanation above (search for F6xx) */ 671 sa->addRange(sa->set, 0, 0xf5ff); 672 sa->addRange(sa->set, 0xf700, 0x10ffff); 673} 674 675/* 676 Here's the basic helper function that we use when converting from 677 Unicode to LMBCS, and we suspect that a Unicode character will fit into 678 one of the 12 groups. The return value is the number of bytes written 679 starting at pStartLMBCS (if any). 680*/ 681 682static size_t 683LMBCSConversionWorker ( 684 UConverterDataLMBCS * extraInfo, /* subconverters, opt & locale groups */ 685 ulmbcs_byte_t group, /* The group to try */ 686 ulmbcs_byte_t * pStartLMBCS, /* where to put the results */ 687 UChar * pUniChar, /* The input unicode character */ 688 ulmbcs_byte_t * lastConverterIndex, /* output: track last successful group used */ 689 UBool * groups_tried /* output: track any unsuccessful groups */ 690) 691{ 692 ulmbcs_byte_t * pLMBCS = pStartLMBCS; 693 UConverterSharedData * xcnv = extraInfo->OptGrpConverter[group]; 694 695 int bytesConverted; 696 uint32_t value; 697 ulmbcs_byte_t firstByte; 698 699 U_ASSERT(xcnv); 700 U_ASSERT(group<ULMBCS_GRP_UNICODE); 701 702 bytesConverted = ucnv_MBCSFromUChar32(xcnv, *pUniChar, &value, FALSE); 703 704 /* get the first result byte */ 705 if(bytesConverted > 0) { 706 firstByte = (ulmbcs_byte_t)(value >> ((bytesConverted - 1) * 8)); 707 } else { 708 /* most common failure mode is an unassigned character */ 709 groups_tried[group] = TRUE; 710 return 0; 711 } 712 713 *lastConverterIndex = group; 714 715 /* All initial byte values in lower ascii range should have been caught by now, 716 except with the exception group. 717 */ 718 U_ASSERT((firstByte <= ULMBCS_C0END) || (firstByte >= ULMBCS_C1START) || (group == ULMBCS_GRP_EXCEPT)); 719 720 /* use converted data: first write 0, 1 or two group bytes */ 721 if (group != ULMBCS_GRP_EXCEPT && extraInfo->OptGroup != group) 722 { 723 *pLMBCS++ = group; 724 if (bytesConverted == 1 && group >= ULMBCS_DOUBLEOPTGROUP_START) 725 { 726 *pLMBCS++ = group; 727 } 728 } 729 730 /* don't emit control chars */ 731 if ( bytesConverted == 1 && firstByte < 0x20 ) 732 return 0; 733 734 735 /* then move over the converted data */ 736 switch(bytesConverted) 737 { 738 case 4: 739 *pLMBCS++ = (ulmbcs_byte_t)(value >> 24); 740 case 3: 741 *pLMBCS++ = (ulmbcs_byte_t)(value >> 16); 742 case 2: 743 *pLMBCS++ = (ulmbcs_byte_t)(value >> 8); 744 case 1: 745 *pLMBCS++ = (ulmbcs_byte_t)value; 746 default: 747 /* will never occur */ 748 break; 749 } 750 751 return (pLMBCS - pStartLMBCS); 752} 753 754 755/* This is a much simpler version of above, when we 756know we are writing LMBCS using the Unicode group 757*/ 758static size_t 759LMBCSConvertUni(ulmbcs_byte_t * pLMBCS, UChar uniChar) 760{ 761 /* encode into LMBCS Unicode range */ 762 uint8_t LowCh = (uint8_t)(uniChar & 0x00FF); 763 uint8_t HighCh = (uint8_t)(uniChar >> 8); 764 765 *pLMBCS++ = ULMBCS_GRP_UNICODE; 766 767 if (LowCh == 0) 768 { 769 *pLMBCS++ = ULMBCS_UNICOMPATZERO; 770 *pLMBCS++ = HighCh; 771 } 772 else 773 { 774 *pLMBCS++ = HighCh; 775 *pLMBCS++ = LowCh; 776 } 777 return ULMBCS_UNICODE_SIZE; 778} 779 780 781 782/* The main Unicode to LMBCS conversion function */ 783static void 784_LMBCSFromUnicode(UConverterFromUnicodeArgs* args, 785 UErrorCode* err) 786{ 787 ulmbcs_byte_t lastConverterIndex = 0; 788 UChar uniChar; 789 ulmbcs_byte_t LMBCS[ULMBCS_CHARSIZE_MAX]; 790 ulmbcs_byte_t * pLMBCS; 791 int bytes_written; 792 UBool groups_tried[ULMBCS_GRP_LAST+1]; 793 UConverterDataLMBCS * extraInfo = (UConverterDataLMBCS *) args->converter->extraInfo; 794 int sourceIndex = 0; 795 796 797 /* Basic strategy: attempt to fill in local LMBCS 1-char buffer.(LMBCS) 798 If that succeeds, see if it will all fit into the target & copy it over 799 if it does. 800 801 We try conversions in the following order: 802 803 1. Single-byte ascii & special fixed control chars (&null) 804 2. Look up group in table & try that (could be 805 A) Unicode group 806 B) control group, 807 C) national encoding, 808 or ambiguous SBCS or MBCS group (on to step 4...) 809 810 3. If its ambiguous, try this order: 811 A) The optimization group 812 B) The locale group 813 C) The last group that succeeded with this string. 814 D) every other group that's relevent (single or double) 815 E) If its single-byte ambiguous, try the exceptions group 816 817 4. And as a grand fallback: Unicode 818 */ 819 820 while (args->source < args->sourceLimit && !U_FAILURE(*err)) 821 { 822 if (args->target >= args->targetLimit) 823 { 824 *err = U_BUFFER_OVERFLOW_ERROR; 825 break; 826 } 827 uniChar = *(args->source); 828 bytes_written = 0; 829 pLMBCS = LMBCS; 830 831 /* check cases in rough order of how common they are, for speed */ 832 833 /* single byte matches: strategy 1 */ 834 835 if (((uniChar > ULMBCS_C0END) && (uniChar < ULMBCS_C1START)) || 836 uniChar == 0 || uniChar == ULMBCS_HT || uniChar == ULMBCS_CR || 837 uniChar == ULMBCS_LF || uniChar == ULMBCS_123SYSTEMRANGE 838 ) 839 { 840 *pLMBCS++ = (ulmbcs_byte_t ) uniChar; 841 bytes_written = 1; 842 } 843 844 845 if (!bytes_written) 846 { 847 /* Check by UNICODE range (Strategy 2) */ 848 ulmbcs_byte_t group = FindLMBCSUniRange(uniChar); 849 850 if (group == ULMBCS_GRP_UNICODE) /* (Strategy 2A) */ 851 { 852 pLMBCS += LMBCSConvertUni(pLMBCS,uniChar); 853 854 bytes_written = pLMBCS - LMBCS; 855 } 856 else if (group == ULMBCS_GRP_CTRL) /* (Strategy 2B) */ 857 { 858 /* Handle control characters here */ 859 if (uniChar <= ULMBCS_C0END) 860 { 861 *pLMBCS++ = ULMBCS_GRP_CTRL; 862 *pLMBCS++ = (ulmbcs_byte_t)(ULMBCS_CTRLOFFSET + uniChar); 863 } 864 else if (uniChar >= ULMBCS_C1START && uniChar <= ULMBCS_C1START + ULMBCS_CTRLOFFSET) 865 { 866 *pLMBCS++ = ULMBCS_GRP_CTRL; 867 *pLMBCS++ = (ulmbcs_byte_t ) (uniChar & 0x00FF); 868 } 869 bytes_written = pLMBCS - LMBCS; 870 } 871 else if (group < ULMBCS_GRP_UNICODE) /* (Strategy 2C) */ 872 { 873 /* a specific converter has been identified - use it */ 874 bytes_written = LMBCSConversionWorker ( 875 extraInfo, group, pLMBCS, &uniChar, 876 &lastConverterIndex, groups_tried); 877 } 878 if (!bytes_written) /* the ambiguous group cases (Strategy 3) */ 879 { 880 uprv_memset(groups_tried, 0, sizeof(groups_tried)); 881 882 /* check for non-default optimization group (Strategy 3A )*/ 883 if (extraInfo->OptGroup != 1 884 && ULMBCS_AMBIGUOUS_MATCH(group, extraInfo->OptGroup)) 885 { 886 bytes_written = LMBCSConversionWorker (extraInfo, 887 extraInfo->OptGroup, pLMBCS, &uniChar, 888 &lastConverterIndex, groups_tried); 889 } 890 /* check for locale optimization group (Strategy 3B) */ 891 if (!bytes_written 892 && (extraInfo->localeConverterIndex) 893 && (ULMBCS_AMBIGUOUS_MATCH(group, extraInfo->localeConverterIndex))) 894 { 895 bytes_written = LMBCSConversionWorker (extraInfo, 896 extraInfo->localeConverterIndex, pLMBCS, &uniChar, 897 &lastConverterIndex, groups_tried); 898 } 899 /* check for last optimization group used for this string (Strategy 3C) */ 900 if (!bytes_written 901 && (lastConverterIndex) 902 && (ULMBCS_AMBIGUOUS_MATCH(group, lastConverterIndex))) 903 { 904 bytes_written = LMBCSConversionWorker (extraInfo, 905 lastConverterIndex, pLMBCS, &uniChar, 906 &lastConverterIndex, groups_tried); 907 908 } 909 if (!bytes_written) 910 { 911 /* just check every possible matching converter (Strategy 3D) */ 912 ulmbcs_byte_t grp_start; 913 ulmbcs_byte_t grp_end; 914 ulmbcs_byte_t grp_ix; 915 grp_start = (ulmbcs_byte_t)((group == ULMBCS_AMBIGUOUS_MBCS) 916 ? ULMBCS_DOUBLEOPTGROUP_START 917 : ULMBCS_GRP_L1); 918 grp_end = (ulmbcs_byte_t)((group == ULMBCS_AMBIGUOUS_MBCS) 919 ? ULMBCS_GRP_LAST 920 : ULMBCS_GRP_TH); 921 for (grp_ix = grp_start; 922 grp_ix <= grp_end && !bytes_written; 923 grp_ix++) 924 { 925 if (extraInfo->OptGrpConverter [grp_ix] && !groups_tried [grp_ix]) 926 { 927 bytes_written = LMBCSConversionWorker (extraInfo, 928 grp_ix, pLMBCS, &uniChar, 929 &lastConverterIndex, groups_tried); 930 } 931 } 932 /* a final conversion fallback to the exceptions group if its likely 933 to be single byte (Strategy 3E) */ 934 if (!bytes_written && grp_start == ULMBCS_GRP_L1) 935 { 936 bytes_written = LMBCSConversionWorker (extraInfo, 937 ULMBCS_GRP_EXCEPT, pLMBCS, &uniChar, 938 &lastConverterIndex, groups_tried); 939 } 940 } 941 /* all of our other strategies failed. Fallback to Unicode. (Strategy 4)*/ 942 if (!bytes_written) 943 { 944 945 pLMBCS += LMBCSConvertUni(pLMBCS, uniChar); 946 bytes_written = pLMBCS - LMBCS; 947 } 948 } 949 } 950 951 /* we have a translation. increment source and write as much as posible to target */ 952 args->source++; 953 pLMBCS = LMBCS; 954 while (args->target < args->targetLimit && bytes_written--) 955 { 956 *(args->target)++ = *pLMBCS++; 957 if (args->offsets) 958 { 959 *(args->offsets)++ = sourceIndex; 960 } 961 } 962 sourceIndex++; 963 if (bytes_written > 0) 964 { 965 /* write any bytes that didn't fit in target to the error buffer, 966 common code will move this to target if we get called back with 967 enough target room 968 */ 969 uint8_t * pErrorBuffer = args->converter->charErrorBuffer; 970 *err = U_BUFFER_OVERFLOW_ERROR; 971 args->converter->charErrorBufferLength = (int8_t)bytes_written; 972 while (bytes_written--) 973 { 974 *pErrorBuffer++ = *pLMBCS++; 975 } 976 } 977 } 978} 979 980 981/* Now, the Unicode from LMBCS section */ 982 983 984/* A function to call when we are looking at the Unicode group byte in LMBCS */ 985static UChar 986GetUniFromLMBCSUni(char const ** ppLMBCSin) /* Called with LMBCS-style Unicode byte stream */ 987{ 988 uint8_t HighCh = *(*ppLMBCSin)++; /* Big-endian Unicode in LMBCS compatibility group*/ 989 uint8_t LowCh = *(*ppLMBCSin)++; 990 991 if (HighCh == ULMBCS_UNICOMPATZERO ) 992 { 993 HighCh = LowCh; 994 LowCh = 0; /* zero-byte in LSB special character */ 995 } 996 return (UChar)((HighCh << 8) | LowCh); 997} 998 999 1000 1001/* CHECK_SOURCE_LIMIT: Helper macro to verify that there are at least'index' 1002 bytes left in source up to sourceLimit.Errors appropriately if not. 1003 If we reach the limit, then update the source pointer to there to consume 1004 all input as required by ICU converter semantics. 1005*/ 1006 1007#define CHECK_SOURCE_LIMIT(index) \ 1008 if (args->source+index > args->sourceLimit){\ 1009 *err = U_TRUNCATED_CHAR_FOUND;\ 1010 args->source = args->sourceLimit;\ 1011 return 0xffff;} 1012 1013/* Return the Unicode representation for the current LMBCS character */ 1014 1015static UChar32 1016_LMBCSGetNextUCharWorker(UConverterToUnicodeArgs* args, 1017 UErrorCode* err) 1018{ 1019 UChar32 uniChar = 0; /* an output UNICODE char */ 1020 ulmbcs_byte_t CurByte; /* A byte from the input stream */ 1021 1022 /* error check */ 1023 if (args->source >= args->sourceLimit) 1024 { 1025 *err = U_ILLEGAL_ARGUMENT_ERROR; 1026 return 0xffff; 1027 } 1028 /* Grab first byte & save address for error recovery */ 1029 CurByte = *((ulmbcs_byte_t *) (args->source++)); 1030 1031 /* 1032 * at entry of each if clause: 1033 * 1. 'CurByte' points at the first byte of a LMBCS character 1034 * 2. '*source'points to the next byte of the source stream after 'CurByte' 1035 * 1036 * the job of each if clause is: 1037 * 1. set '*source' to point at the beginning of next char (nop if LMBCS char is only 1 byte) 1038 * 2. set 'uniChar' up with the right Unicode value, or set 'err' appropriately 1039 */ 1040 1041 /* First lets check the simple fixed values. */ 1042 1043 if(((CurByte > ULMBCS_C0END) && (CurByte < ULMBCS_C1START)) /* ascii range */ 1044 || (CurByte == 0) 1045 || CurByte == ULMBCS_HT || CurByte == ULMBCS_CR 1046 || CurByte == ULMBCS_LF || CurByte == ULMBCS_123SYSTEMRANGE) 1047 { 1048 uniChar = CurByte; 1049 } 1050 else 1051 { 1052 UConverterDataLMBCS * extraInfo; 1053 ulmbcs_byte_t group; 1054 UConverterSharedData *cnv; 1055 1056 if (CurByte == ULMBCS_GRP_CTRL) /* Control character group - no opt group update */ 1057 { 1058 ulmbcs_byte_t C0C1byte; 1059 CHECK_SOURCE_LIMIT(1); 1060 C0C1byte = *(args->source)++; 1061 uniChar = (C0C1byte < ULMBCS_C1START) ? C0C1byte - ULMBCS_CTRLOFFSET : C0C1byte; 1062 } 1063 else 1064 if (CurByte == ULMBCS_GRP_UNICODE) /* Unicode compatibility group: BigEndian UTF16 */ 1065 { 1066 CHECK_SOURCE_LIMIT(2); 1067 1068 /* don't check for error indicators fffe/ffff below */ 1069 return GetUniFromLMBCSUni(&(args->source)); 1070 } 1071 else if (CurByte <= ULMBCS_CTRLOFFSET) 1072 { 1073 group = CurByte; /* group byte is in the source */ 1074 extraInfo = (UConverterDataLMBCS *) args->converter->extraInfo; 1075 if (group > ULMBCS_GRP_LAST || (cnv = extraInfo->OptGrpConverter[group]) == NULL) 1076 { 1077 /* this is not a valid group byte - no converter*/ 1078 *err = U_INVALID_CHAR_FOUND; 1079 } 1080 else if (group >= ULMBCS_DOUBLEOPTGROUP_START) /* double byte conversion */ 1081 { 1082 1083 CHECK_SOURCE_LIMIT(2); 1084 1085 /* check for LMBCS doubled-group-byte case */ 1086 if (*args->source == group) { 1087 /* single byte */ 1088 ++args->source; 1089 uniChar = ucnv_MBCSSimpleGetNextUChar(cnv, args->source, 1, FALSE); 1090 ++args->source; 1091 } else { 1092 /* double byte */ 1093 uniChar = ucnv_MBCSSimpleGetNextUChar(cnv, args->source, 2, FALSE); 1094 args->source += 2; 1095 } 1096 } 1097 else { /* single byte conversion */ 1098 CHECK_SOURCE_LIMIT(1); 1099 CurByte = *(args->source)++; 1100 1101 if (CurByte >= ULMBCS_C1START) 1102 { 1103 uniChar = _MBCS_SINGLE_SIMPLE_GET_NEXT_BMP(cnv, CurByte); 1104 } 1105 else 1106 { 1107 /* The non-optimizable oddballs where there is an explicit byte 1108 * AND the second byte is not in the upper ascii range 1109 */ 1110 char bytes[2]; 1111 1112 extraInfo = (UConverterDataLMBCS *) args->converter->extraInfo; 1113 cnv = extraInfo->OptGrpConverter [ULMBCS_GRP_EXCEPT]; 1114 1115 /* Lookup value must include opt group */ 1116 bytes[0] = group; 1117 bytes[1] = CurByte; 1118 uniChar = ucnv_MBCSSimpleGetNextUChar(cnv, bytes, 2, FALSE); 1119 } 1120 } 1121 } 1122 else if (CurByte >= ULMBCS_C1START) /* group byte is implicit */ 1123 { 1124 extraInfo = (UConverterDataLMBCS *) args->converter->extraInfo; 1125 group = extraInfo->OptGroup; 1126 cnv = extraInfo->OptGrpConverter[group]; 1127 if (group >= ULMBCS_DOUBLEOPTGROUP_START) /* double byte conversion */ 1128 { 1129 if (!ucnv_MBCSIsLeadByte(cnv, CurByte)) 1130 { 1131 CHECK_SOURCE_LIMIT(0); 1132 1133 /* let the MBCS conversion consume CurByte again */ 1134 uniChar = ucnv_MBCSSimpleGetNextUChar(cnv, args->source - 1, 1, FALSE); 1135 } 1136 else 1137 { 1138 CHECK_SOURCE_LIMIT(1); 1139 /* let the MBCS conversion consume CurByte again */ 1140 uniChar = ucnv_MBCSSimpleGetNextUChar(cnv, args->source - 1, 2, FALSE); 1141 ++args->source; 1142 } 1143 } 1144 else /* single byte conversion */ 1145 { 1146 uniChar = _MBCS_SINGLE_SIMPLE_GET_NEXT_BMP(cnv, CurByte); 1147 } 1148 } 1149 } 1150 return uniChar; 1151} 1152 1153 1154/* The exported function that converts lmbcs to one or more 1155 UChars - currently UTF-16 1156*/ 1157static void 1158_LMBCSToUnicodeWithOffsets(UConverterToUnicodeArgs* args, 1159 UErrorCode* err) 1160{ 1161 char LMBCS [ULMBCS_CHARSIZE_MAX]; 1162 UChar uniChar; /* one output UNICODE char */ 1163 const char * saveSource; /* beginning of current code point */ 1164 const char * pStartLMBCS = args->source; /* beginning of whole string */ 1165 const char * errSource = NULL; /* pointer to actual input in case an error occurs */ 1166 int8_t savebytes = 0; 1167 1168 /* Process from source to limit, or until error */ 1169 while (U_SUCCESS(*err) && args->sourceLimit > args->source && args->targetLimit > args->target) 1170 { 1171 saveSource = args->source; /* beginning of current code point */ 1172 1173 if (args->converter->toULength) /* reassemble char from previous call */ 1174 { 1175 const char *saveSourceLimit; 1176 size_t size_old = args->converter->toULength; 1177 1178 /* limit from source is either remainder of temp buffer, or user limit on source */ 1179 size_t size_new_maybe_1 = sizeof(LMBCS) - size_old; 1180 size_t size_new_maybe_2 = args->sourceLimit - args->source; 1181 size_t size_new = (size_new_maybe_1 < size_new_maybe_2) ? size_new_maybe_1 : size_new_maybe_2; 1182 1183 1184 uprv_memcpy(LMBCS, args->converter->toUBytes, size_old); 1185 uprv_memcpy(LMBCS + size_old, args->source, size_new); 1186 saveSourceLimit = args->sourceLimit; 1187 args->source = errSource = LMBCS; 1188 args->sourceLimit = LMBCS+size_old+size_new; 1189 savebytes = (int8_t)(size_old+size_new); 1190 uniChar = (UChar) _LMBCSGetNextUCharWorker(args, err); 1191 args->source = saveSource + ((args->source - LMBCS) - size_old); 1192 args->sourceLimit = saveSourceLimit; 1193 1194 if (*err == U_TRUNCATED_CHAR_FOUND) 1195 { 1196 /* evil special case: source buffers so small a char spans more than 2 buffers */ 1197 args->converter->toULength = savebytes; 1198 uprv_memcpy(args->converter->toUBytes, LMBCS, savebytes); 1199 args->source = args->sourceLimit; 1200 *err = U_ZERO_ERROR; 1201 return; 1202 } 1203 else 1204 { 1205 /* clear the partial-char marker */ 1206 args->converter->toULength = 0; 1207 } 1208 } 1209 else 1210 { 1211 errSource = saveSource; 1212 uniChar = (UChar) _LMBCSGetNextUCharWorker(args, err); 1213 savebytes = (int8_t)(args->source - saveSource); 1214 } 1215 if (U_SUCCESS(*err)) 1216 { 1217 if (uniChar < 0xfffe) 1218 { 1219 *(args->target)++ = uniChar; 1220 if(args->offsets) 1221 { 1222 *(args->offsets)++ = saveSource - pStartLMBCS; 1223 } 1224 } 1225 else if (uniChar == 0xfffe) 1226 { 1227 *err = U_INVALID_CHAR_FOUND; 1228 } 1229 else /* if (uniChar == 0xffff) */ 1230 { 1231 *err = U_ILLEGAL_CHAR_FOUND; 1232 } 1233 } 1234 } 1235 /* if target ran out before source, return U_BUFFER_OVERFLOW_ERROR */ 1236 if (U_SUCCESS(*err) && args->sourceLimit > args->source && args->targetLimit <= args->target) 1237 { 1238 *err = U_BUFFER_OVERFLOW_ERROR; 1239 } 1240 else if (U_FAILURE(*err)) 1241 { 1242 /* If character incomplete or unmappable/illegal, store it in toUBytes[] */ 1243 args->converter->toULength = savebytes; 1244 if (savebytes > 0) { 1245 uprv_memcpy(args->converter->toUBytes, errSource, savebytes); 1246 } 1247 if (*err == U_TRUNCATED_CHAR_FOUND) { 1248 *err = U_ZERO_ERROR; 1249 } 1250 } 1251} 1252 1253/* And now, the macroized declarations of data & functions: */ 1254DEFINE_LMBCS_OPEN(1) 1255DEFINE_LMBCS_OPEN(2) 1256DEFINE_LMBCS_OPEN(3) 1257DEFINE_LMBCS_OPEN(4) 1258DEFINE_LMBCS_OPEN(5) 1259DEFINE_LMBCS_OPEN(6) 1260DEFINE_LMBCS_OPEN(8) 1261DEFINE_LMBCS_OPEN(11) 1262DEFINE_LMBCS_OPEN(16) 1263DEFINE_LMBCS_OPEN(17) 1264DEFINE_LMBCS_OPEN(18) 1265DEFINE_LMBCS_OPEN(19) 1266 1267 1268DECLARE_LMBCS_DATA(1) 1269DECLARE_LMBCS_DATA(2) 1270DECLARE_LMBCS_DATA(3) 1271DECLARE_LMBCS_DATA(4) 1272DECLARE_LMBCS_DATA(5) 1273DECLARE_LMBCS_DATA(6) 1274DECLARE_LMBCS_DATA(8) 1275DECLARE_LMBCS_DATA(11) 1276DECLARE_LMBCS_DATA(16) 1277DECLARE_LMBCS_DATA(17) 1278DECLARE_LMBCS_DATA(18) 1279DECLARE_LMBCS_DATA(19) 1280 1281#endif /* #if !UCONFIG_NO_LEGACY_CONVERSION */ 1282