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      1 /*
      2 ******************************************************************************
      3 *
      4 *   Copyright (C) 1999-2012, International Business Machines
      5 *   Corporation and others.  All Rights Reserved.
      6 *
      7 ******************************************************************************
      8 *   file name:  udata.cpp
      9 *   encoding:   US-ASCII
     10 *   tab size:   8 (not used)
     11 *   indentation:4
     12 *
     13 *   created on: 1999oct25
     14 *   created by: Markus W. Scherer
     15 */
     16 
     17 #include "unicode/utypes.h"  /* U_PLATFORM etc. */
     18 
     19 #ifdef __GNUC__
     20 /* if gcc
     21 #define ATTRIBUTE_WEAK __attribute__ ((weak))
     22 might have to #include some other header
     23 */
     24 #endif
     25 
     26 #include "unicode/putil.h"
     27 #include "unicode/udata.h"
     28 #include "unicode/uversion.h"
     29 #include "charstr.h"
     30 #include "cmemory.h"
     31 #include "cstring.h"
     32 #include "putilimp.h"
     33 #include "ucln_cmn.h"
     34 #include "ucmndata.h"
     35 #include "udatamem.h"
     36 #include "uhash.h"
     37 #include "umapfile.h"
     38 #include "umutex.h"
     39 
     40 /***********************************************************************
     41 *
     42 *   Notes on the organization of the ICU data implementation
     43 *
     44 *      All of the public API is defined in udata.h
     45 *
     46 *      The implementation is split into several files...
     47 *
     48 *         - udata.c  (this file) contains higher level code that knows about
     49 *                     the search paths for locating data, caching opened data, etc.
     50 *
     51 *         - umapfile.c  contains the low level platform-specific code for actually loading
     52 *                     (memory mapping, file reading, whatever) data into memory.
     53 *
     54 *         - ucmndata.c  deals with the tables of contents of ICU data items within
     55 *                     an ICU common format data file.  The implementation includes
     56 *                     an abstract interface and support for multiple TOC formats.
     57 *                     All knowledge of any specific TOC format is encapsulated here.
     58 *
     59 *         - udatamem.c has code for managing UDataMemory structs.  These are little
     60 *                     descriptor objects for blocks of memory holding ICU data of
     61 *                     various types.
     62 */
     63 
     64 /* configuration ---------------------------------------------------------- */
     65 
     66 /* If you are excruciatingly bored turn this on .. */
     67 /* #define UDATA_DEBUG 1 */
     68 
     69 #if defined(UDATA_DEBUG)
     70 #   include <stdio.h>
     71 #endif
     72 
     73 #define LENGTHOF(array) (int32_t)(sizeof(array)/sizeof((array)[0]))
     74 
     75 U_NAMESPACE_USE
     76 
     77 /*
     78  *  Forward declarations
     79  */
     80 static UDataMemory *udata_findCachedData(const char *path);
     81 
     82 /***********************************************************************
     83 *
     84 *    static (Global) data
     85 *
     86 ************************************************************************/
     87 
     88 /*
     89  * Pointers to the common ICU data.
     90  *
     91  * We store multiple pointers to ICU data packages and iterate through them
     92  * when looking for a data item.
     93  *
     94  * It is possible to combine this with dependency inversion:
     95  * One or more data package libraries may export
     96  * functions that each return a pointer to their piece of the ICU data,
     97  * and this file would import them as weak functions, without a
     98  * strong linker dependency from the common library on the data library.
     99  *
    100  * Then we can have applications depend on only that part of ICU's data
    101  * that they really need, reducing the size of binaries that take advantage
    102  * of this.
    103  */
    104 static UDataMemory *gCommonICUDataArray[10] = { NULL };
    105 
    106 static UBool gHaveTriedToLoadCommonData = FALSE;  /* See extendICUData(). */
    107 
    108 static UHashtable  *gCommonDataCache = NULL;  /* Global hash table of opened ICU data files.  */
    109 
    110 static UDataFileAccess  gDataFileAccess = UDATA_DEFAULT_ACCESS;
    111 
    112 static UBool U_CALLCONV
    113 udata_cleanup(void)
    114 {
    115     int32_t i;
    116 
    117     if (gCommonDataCache) {             /* Delete the cache of user data mappings.  */
    118         uhash_close(gCommonDataCache);  /*   Table owns the contents, and will delete them. */
    119         gCommonDataCache = NULL;        /*   Cleanup is not thread safe.                */
    120     }
    121 
    122     for (i = 0; i < LENGTHOF(gCommonICUDataArray) && gCommonICUDataArray[i] != NULL; ++i) {
    123         udata_close(gCommonICUDataArray[i]);
    124         gCommonICUDataArray[i] = NULL;
    125     }
    126     gHaveTriedToLoadCommonData = FALSE;
    127 
    128     return TRUE;                   /* Everything was cleaned up */
    129 }
    130 
    131 static UBool U_CALLCONV
    132 findCommonICUDataByName(const char *inBasename)
    133 {
    134     UBool found = FALSE;
    135     int32_t i;
    136 
    137     UDataMemory  *pData = udata_findCachedData(inBasename);
    138     if (pData == NULL)
    139         return FALSE;
    140 
    141     for (i = 0; i < LENGTHOF(gCommonICUDataArray); ++i) {
    142         if ((gCommonICUDataArray[i] != NULL) && (gCommonICUDataArray[i]->pHeader == pData->pHeader)) {
    143             /* The data pointer is already in the array. */
    144             found = TRUE;
    145             break;
    146         }
    147     }
    148 
    149     return found;
    150 }
    151 
    152 
    153 /*
    154  * setCommonICUData.   Set a UDataMemory to be the global ICU Data
    155  */
    156 static UBool
    157 setCommonICUData(UDataMemory *pData,     /*  The new common data.  Belongs to caller, we copy it. */
    158                  UBool       warn,       /*  If true, set USING_DEFAULT warning if ICUData was    */
    159                                          /*    changed by another thread before we got to it.     */
    160                  UErrorCode *pErr)
    161 {
    162     UDataMemory  *newCommonData = UDataMemory_createNewInstance(pErr);
    163     int32_t i;
    164     UBool didUpdate = FALSE;
    165     if (U_FAILURE(*pErr)) {
    166         return FALSE;
    167     }
    168 
    169     /*  For the assignment, other threads must cleanly see either the old            */
    170     /*    or the new, not some partially initialized new.  The old can not be        */
    171     /*    deleted - someone may still have a pointer to it lying around in           */
    172     /*    their locals.                                                              */
    173     UDatamemory_assign(newCommonData, pData);
    174     umtx_lock(NULL);
    175     for (i = 0; i < LENGTHOF(gCommonICUDataArray); ++i) {
    176         if (gCommonICUDataArray[i] == NULL) {
    177             gCommonICUDataArray[i] = newCommonData;
    178             ucln_common_registerCleanup(UCLN_COMMON_UDATA, udata_cleanup);
    179             didUpdate = TRUE;
    180             break;
    181         } else if (gCommonICUDataArray[i]->pHeader == pData->pHeader) {
    182             /* The same data pointer is already in the array. */
    183             break;
    184         }
    185     }
    186     umtx_unlock(NULL);
    187 
    188     if (i == LENGTHOF(gCommonICUDataArray) && warn) {
    189         *pErr = U_USING_DEFAULT_WARNING;
    190     }
    191     if (!didUpdate) {
    192         uprv_free(newCommonData);
    193     }
    194     return didUpdate;
    195 }
    196 
    197 static UBool
    198 setCommonICUDataPointer(const void *pData, UBool /*warn*/, UErrorCode *pErrorCode) {
    199     UDataMemory tData;
    200     UDataMemory_init(&tData);
    201     tData.pHeader = (const DataHeader *)pData;
    202     udata_checkCommonData(&tData, pErrorCode);
    203     return setCommonICUData(&tData, FALSE, pErrorCode);
    204 }
    205 
    206 static const char *
    207 findBasename(const char *path) {
    208     const char *basename=uprv_strrchr(path, U_FILE_SEP_CHAR);
    209     if(basename==NULL) {
    210         return path;
    211     } else {
    212         return basename+1;
    213     }
    214 }
    215 
    216 #ifdef UDATA_DEBUG
    217 static const char *
    218 packageNameFromPath(const char *path)
    219 {
    220     if((path == NULL) || (*path == 0)) {
    221         return U_ICUDATA_NAME;
    222     }
    223 
    224     path = findBasename(path);
    225 
    226     if((path == NULL) || (*path == 0)) {
    227         return U_ICUDATA_NAME;
    228     }
    229 
    230     return path;
    231 }
    232 #endif
    233 
    234 /*----------------------------------------------------------------------*
    235  *                                                                      *
    236  *   Cache for common data                                              *
    237  *      Functions for looking up or adding entries to a cache of        *
    238  *      data that has been previously opened.  Avoids a potentially     *
    239  *      expensive operation of re-opening the data for subsequent       *
    240  *      uses.                                                           *
    241  *                                                                      *
    242  *      Data remains cached for the duration of the process.            *
    243  *                                                                      *
    244  *----------------------------------------------------------------------*/
    245 
    246 typedef struct DataCacheElement {
    247     char          *name;
    248     UDataMemory   *item;
    249 } DataCacheElement;
    250 
    251 
    252 
    253 /*
    254  * Deleter function for DataCacheElements.
    255  *         udata cleanup function closes the hash table; hash table in turn calls back to
    256  *         here for each entry.
    257  */
    258 static void U_CALLCONV DataCacheElement_deleter(void *pDCEl) {
    259     DataCacheElement *p = (DataCacheElement *)pDCEl;
    260     udata_close(p->item);              /* unmaps storage */
    261     uprv_free(p->name);                /* delete the hash key string. */
    262     uprv_free(pDCEl);                  /* delete 'this'          */
    263 }
    264 
    265  /*   udata_getCacheHashTable()
    266  *     Get the hash table used to store the data cache entries.
    267  *     Lazy create it if it doesn't yet exist.
    268  */
    269 static UHashtable *udata_getHashTable() {
    270     UErrorCode   err = U_ZERO_ERROR;
    271     UBool        cacheIsInitialized;
    272     UHashtable  *tHT = NULL;
    273 
    274     UMTX_CHECK(NULL, (gCommonDataCache != NULL), cacheIsInitialized);
    275 
    276     if (cacheIsInitialized) {
    277         return gCommonDataCache;
    278     }
    279 
    280     tHT = uhash_open(uhash_hashChars, uhash_compareChars, NULL, &err);
    281     /* Check for null pointer. */
    282     if (tHT == NULL) {
    283     	return NULL; /* TODO:  Handle this error better. */
    284     }
    285     uhash_setValueDeleter(tHT, DataCacheElement_deleter);
    286 
    287     umtx_lock(NULL);
    288     if (gCommonDataCache == NULL) {
    289         gCommonDataCache = tHT;
    290         tHT = NULL;
    291         ucln_common_registerCleanup(UCLN_COMMON_UDATA, udata_cleanup);
    292     }
    293     umtx_unlock(NULL);
    294     if (tHT != NULL) {
    295         uhash_close(tHT);
    296     }
    297 
    298     if (U_FAILURE(err)) {
    299         return NULL;      /* TODO:  handle this error better.  */
    300     }
    301     return gCommonDataCache;
    302 }
    303 
    304 
    305 
    306 static UDataMemory *udata_findCachedData(const char *path)
    307 {
    308     UHashtable        *htable;
    309     UDataMemory       *retVal = NULL;
    310     DataCacheElement  *el;
    311     const char        *baseName;
    312 
    313     baseName = findBasename(path);   /* Cache remembers only the base name, not the full path. */
    314     htable = udata_getHashTable();
    315     umtx_lock(NULL);
    316     el = (DataCacheElement *)uhash_get(htable, baseName);
    317     umtx_unlock(NULL);
    318     if (el != NULL) {
    319         retVal = el->item;
    320     }
    321 #ifdef UDATA_DEBUG
    322     fprintf(stderr, "Cache: [%s] -> %p\n", baseName, retVal);
    323 #endif
    324     return retVal;
    325 }
    326 
    327 
    328 static UDataMemory *udata_cacheDataItem(const char *path, UDataMemory *item, UErrorCode *pErr) {
    329     DataCacheElement *newElement;
    330     const char       *baseName;
    331     int32_t           nameLen;
    332     UHashtable       *htable;
    333     DataCacheElement *oldValue = NULL;
    334     UErrorCode        subErr = U_ZERO_ERROR;
    335 
    336     if (U_FAILURE(*pErr)) {
    337         return NULL;
    338     }
    339 
    340     /* Create a new DataCacheElement - the thingy we store in the hash table -
    341      * and copy the supplied path and UDataMemoryItems into it.
    342      */
    343     newElement = (DataCacheElement *)uprv_malloc(sizeof(DataCacheElement));
    344     if (newElement == NULL) {
    345         *pErr = U_MEMORY_ALLOCATION_ERROR;
    346         return NULL;
    347     }
    348     newElement->item = UDataMemory_createNewInstance(pErr);
    349     if (U_FAILURE(*pErr)) {
    350         uprv_free(newElement);
    351         return NULL;
    352     }
    353     UDatamemory_assign(newElement->item, item);
    354 
    355     baseName = findBasename(path);
    356     nameLen = (int32_t)uprv_strlen(baseName);
    357     newElement->name = (char *)uprv_malloc(nameLen+1);
    358     if (newElement->name == NULL) {
    359         *pErr = U_MEMORY_ALLOCATION_ERROR;
    360         uprv_free(newElement->item);
    361         uprv_free(newElement);
    362         return NULL;
    363     }
    364     uprv_strcpy(newElement->name, baseName);
    365 
    366     /* Stick the new DataCacheElement into the hash table.
    367     */
    368     htable = udata_getHashTable();
    369     umtx_lock(NULL);
    370     oldValue = (DataCacheElement *)uhash_get(htable, path);
    371     if (oldValue != NULL) {
    372         subErr = U_USING_DEFAULT_WARNING;
    373     }
    374     else {
    375         uhash_put(
    376             htable,
    377             newElement->name,               /* Key   */
    378             newElement,                     /* Value */
    379             &subErr);
    380     }
    381     umtx_unlock(NULL);
    382 
    383 #ifdef UDATA_DEBUG
    384     fprintf(stderr, "Cache: [%s] <<< %p : %s. vFunc=%p\n", newElement->name,
    385     newElement->item, u_errorName(subErr), newElement->item->vFuncs);
    386 #endif
    387 
    388     if (subErr == U_USING_DEFAULT_WARNING || U_FAILURE(subErr)) {
    389         *pErr = subErr; /* copy sub err unto fillin ONLY if something happens. */
    390         uprv_free(newElement->name);
    391         uprv_free(newElement->item);
    392         uprv_free(newElement);
    393         return oldValue ? oldValue->item : NULL;
    394     }
    395 
    396     return newElement->item;
    397 }
    398 
    399 /*----------------------------------------------------------------------*==============
    400  *                                                                      *
    401  *  Path management.  Could be shared with other tools/etc if need be   *
    402  * later on.                                                            *
    403  *                                                                      *
    404  *----------------------------------------------------------------------*/
    405 
    406 #define U_DATA_PATHITER_BUFSIZ  128        /* Size of local buffer for paths         */
    407                                            /*   Overflow causes malloc of larger buf */
    408 
    409 U_NAMESPACE_BEGIN
    410 
    411 class UDataPathIterator
    412 {
    413 public:
    414     UDataPathIterator(const char *path, const char *pkg,
    415                       const char *item, const char *suffix, UBool doCheckLastFour,
    416                       UErrorCode *pErrorCode);
    417     const char *next(UErrorCode *pErrorCode);
    418 
    419 private:
    420     const char *path;                              /* working path (u_icudata_Dir) */
    421     const char *nextPath;                          /* path following this one */
    422     const char *basename;                          /* item's basename (icudt22e_mt.res)*/
    423     const char *suffix;                            /* item suffix (can be null) */
    424 
    425     uint32_t    basenameLen;                       /* length of basename */
    426 
    427     CharString  itemPath;                          /* path passed in with item name */
    428     CharString  pathBuffer;                        /* output path for this it'ion */
    429     CharString  packageStub;                       /* example:  "/icudt28b". Will ignore that leaf in set paths. */
    430 
    431     UBool       checkLastFour;                     /* if TRUE then allow paths such as '/foo/myapp.dat'
    432                                                     * to match, checks last 4 chars of suffix with
    433                                                     * last 4 of path, then previous chars. */
    434 };
    435 
    436 /**
    437  * @param iter  The iterator to be initialized. Its current state does not matter.
    438  * @param path  The full pathname to be iterated over.  If NULL, defaults to U_ICUDATA_NAME
    439  * @param pkg   Package which is being searched for, ex "icudt28l".  Will ignore leave directories such as /icudt28l
    440  * @param item  Item to be searched for.  Can include full path, such as /a/b/foo.dat
    441  * @param suffix  Optional item suffix, if not-null (ex. ".dat") then 'path' can contain 'item' explicitly.
    442  *               Ex:   'stuff.dat' would be found in '/a/foo:/tmp/stuff.dat:/bar/baz' as item #2.
    443  *                     '/blarg/stuff.dat' would also be found.
    444  */
    445 UDataPathIterator::UDataPathIterator(const char *inPath, const char *pkg,
    446                                      const char *item, const char *inSuffix, UBool doCheckLastFour,
    447                                      UErrorCode *pErrorCode)
    448 {
    449 #ifdef UDATA_DEBUG
    450         fprintf(stderr, "SUFFIX1=%s PATH=%s\n", inSuffix, inPath);
    451 #endif
    452     /** Path **/
    453     if(inPath == NULL) {
    454         path = u_getDataDirectory();
    455     } else {
    456         path = inPath;
    457     }
    458 
    459     /** Package **/
    460     if(pkg != NULL) {
    461       packageStub.append(U_FILE_SEP_CHAR, *pErrorCode).append(pkg, *pErrorCode);
    462 #ifdef UDATA_DEBUG
    463       fprintf(stderr, "STUB=%s [%d]\n", packageStub.data(), packageStub.length());
    464 #endif
    465     }
    466 
    467     /** Item **/
    468     basename = findBasename(item);
    469     basenameLen = (int32_t)uprv_strlen(basename);
    470 
    471     /** Item path **/
    472     if(basename == item) {
    473         nextPath = path;
    474     } else {
    475         itemPath.append(item, (int32_t)(basename-item), *pErrorCode);
    476         nextPath = itemPath.data();
    477     }
    478 #ifdef UDATA_DEBUG
    479     fprintf(stderr, "SUFFIX=%s [%p]\n", inSuffix, inSuffix);
    480 #endif
    481 
    482     /** Suffix  **/
    483     if(inSuffix != NULL) {
    484         suffix = inSuffix;
    485     } else {
    486         suffix = "";
    487     }
    488 
    489     checkLastFour = doCheckLastFour;
    490 
    491     /* pathBuffer will hold the output path strings returned by this iterator */
    492 
    493 #ifdef UDATA_DEBUG
    494     fprintf(stderr, "%p: init %s -> [path=%s], [base=%s], [suff=%s], [itempath=%s], [nextpath=%s], [checklast4=%s]\n",
    495             iter,
    496             item,
    497             path,
    498             basename,
    499             suffix,
    500             itemPath.data(),
    501             nextPath,
    502             checkLastFour?"TRUE":"false");
    503 #endif
    504 }
    505 
    506 /**
    507  * Get the next path on the list.
    508  *
    509  * @param iter The Iter to be used
    510  * @param len  If set, pointer to the length of the returned path, for convenience.
    511  * @return Pointer to the next path segment, or NULL if there are no more.
    512  */
    513 const char *UDataPathIterator::next(UErrorCode *pErrorCode)
    514 {
    515     if(U_FAILURE(*pErrorCode)) {
    516         return NULL;
    517     }
    518 
    519     const char *currentPath = NULL;
    520     int32_t     pathLen = 0;
    521     const char *pathBasename;
    522 
    523     do
    524     {
    525         if( nextPath == NULL ) {
    526             break;
    527         }
    528         currentPath = nextPath;
    529 
    530         if(nextPath == itemPath.data()) { /* we were processing item's path. */
    531             nextPath = path; /* start with regular path next tm. */
    532             pathLen = (int32_t)uprv_strlen(currentPath);
    533         } else {
    534             /* fix up next for next time */
    535             nextPath = uprv_strchr(currentPath, U_PATH_SEP_CHAR);
    536             if(nextPath == NULL) {
    537                 /* segment: entire path */
    538                 pathLen = (int32_t)uprv_strlen(currentPath);
    539             } else {
    540                 /* segment: until next segment */
    541                 pathLen = (int32_t)(nextPath - currentPath);
    542                 /* skip divider */
    543                 nextPath ++;
    544             }
    545         }
    546 
    547         if(pathLen == 0) {
    548             continue;
    549         }
    550 
    551 #ifdef UDATA_DEBUG
    552         fprintf(stderr, "rest of path (IDD) = %s\n", currentPath);
    553         fprintf(stderr, "                     ");
    554         {
    555             uint32_t qqq;
    556             for(qqq=0;qqq<pathLen;qqq++)
    557             {
    558                 fprintf(stderr, " ");
    559             }
    560 
    561             fprintf(stderr, "^\n");
    562         }
    563 #endif
    564         pathBuffer.clear().append(currentPath, pathLen, *pErrorCode);
    565 
    566         /* check for .dat files */
    567         pathBasename = findBasename(pathBuffer.data());
    568 
    569         if(checkLastFour == TRUE &&
    570            (pathLen>=4) &&
    571            uprv_strncmp(pathBuffer.data() +(pathLen-4), suffix, 4)==0 && /* suffix matches */
    572            uprv_strncmp(findBasename(pathBuffer.data()), basename, basenameLen)==0  && /* base matches */
    573            uprv_strlen(pathBasename)==(basenameLen+4)) { /* base+suffix = full len */
    574 
    575 #ifdef UDATA_DEBUG
    576             fprintf(stderr, "Have %s file on the path: %s\n", suffix, pathBuffer.data());
    577 #endif
    578             /* do nothing */
    579         }
    580         else
    581         {       /* regular dir path */
    582             if(pathBuffer[pathLen-1] != U_FILE_SEP_CHAR) {
    583                 if((pathLen>=4) &&
    584                    uprv_strncmp(pathBuffer.data()+(pathLen-4), ".dat", 4) == 0)
    585                 {
    586 #ifdef UDATA_DEBUG
    587                     fprintf(stderr, "skipping non-directory .dat file %s\n", pathBuffer.data());
    588 #endif
    589                     continue;
    590                 }
    591 
    592                 /* Check if it is a directory with the same name as our package */
    593                 if(!packageStub.isEmpty() &&
    594                    (pathLen > packageStub.length()) &&
    595                    !uprv_strcmp(pathBuffer.data() + pathLen - packageStub.length(), packageStub.data())) {
    596 #ifdef UDATA_DEBUG
    597                   fprintf(stderr, "Found stub %s (will add package %s of len %d)\n", packageStub.data(), basename, basenameLen);
    598 #endif
    599                   pathBuffer.truncate(pathLen - packageStub.length());
    600                 }
    601                 pathBuffer.append(U_FILE_SEP_CHAR, *pErrorCode);
    602             }
    603 
    604             /* + basename */
    605             pathBuffer.append(packageStub.data()+1, packageStub.length()-1, *pErrorCode);
    606 
    607             if(*suffix)  /* tack on suffix */
    608             {
    609                 pathBuffer.append(suffix, *pErrorCode);
    610             }
    611         }
    612 
    613 #ifdef UDATA_DEBUG
    614         fprintf(stderr, " -->  %s\n", pathBuffer.data());
    615 #endif
    616 
    617         return pathBuffer.data();
    618 
    619     } while(path);
    620 
    621     /* fell way off the end */
    622     return NULL;
    623 }
    624 
    625 U_NAMESPACE_END
    626 
    627 /* ==================================================================================*/
    628 
    629 
    630 /*----------------------------------------------------------------------*
    631  *                                                                      *
    632  *  Add a static reference to the common data  library                  *
    633  *   Unless overridden by an explicit udata_setCommonData, this will be *
    634  *      our common data.                                                *
    635  *                                                                      *
    636  *----------------------------------------------------------------------*/
    637 extern "C" const DataHeader U_DATA_API U_ICUDATA_ENTRY_POINT;
    638 
    639 /*
    640  * This would be a good place for weak-linkage declarations of
    641  * partial-data-library access functions where each returns a pointer
    642  * to its data package, if it is linked in.
    643  */
    644 /*
    645 extern const void *uprv_getICUData_collation(void) ATTRIBUTE_WEAK;
    646 extern const void *uprv_getICUData_conversion(void) ATTRIBUTE_WEAK;
    647 */
    648 
    649 /*----------------------------------------------------------------------*
    650  *                                                                      *
    651  *   openCommonData   Attempt to open a common format (.dat) file       *
    652  *                    Map it into memory (if it's not there already)    *
    653  *                    and return a UDataMemory object for it.           *
    654  *                                                                      *
    655  *                    If the requested data is already open and cached  *
    656  *                       just return the cached UDataMem object.        *
    657  *                                                                      *
    658  *----------------------------------------------------------------------*/
    659 static UDataMemory *
    660 openCommonData(const char *path,          /*  Path from OpenChoice?          */
    661                int32_t commonDataIndex,   /*  ICU Data (index >= 0) if path == NULL */
    662                UErrorCode *pErrorCode)
    663 {
    664     UDataMemory tData;
    665     const char *pathBuffer;
    666     const char *inBasename;
    667 
    668     if (U_FAILURE(*pErrorCode)) {
    669         return NULL;
    670     }
    671 
    672     UDataMemory_init(&tData);
    673 
    674     /* ??????? TODO revisit this */
    675     if (commonDataIndex >= 0) {
    676         /* "mini-cache" for common ICU data */
    677         if(commonDataIndex >= LENGTHOF(gCommonICUDataArray)) {
    678             return NULL;
    679         }
    680         if(gCommonICUDataArray[commonDataIndex] == NULL) {
    681             int32_t i;
    682             for(i = 0; i < commonDataIndex; ++i) {
    683                 if(gCommonICUDataArray[i]->pHeader == &U_ICUDATA_ENTRY_POINT) {
    684                     /* The linked-in data is already in the list. */
    685                     return NULL;
    686                 }
    687             }
    688 
    689             /* Add the linked-in data to the list. */
    690             /*
    691              * This is where we would check and call weakly linked partial-data-library
    692              * access functions.
    693              */
    694             /*
    695             if (uprv_getICUData_collation) {
    696                 setCommonICUDataPointer(uprv_getICUData_collation(), FALSE, pErrorCode);
    697             }
    698             if (uprv_getICUData_conversion) {
    699                 setCommonICUDataPointer(uprv_getICUData_conversion(), FALSE, pErrorCode);
    700             }
    701             */
    702             setCommonICUDataPointer(&U_ICUDATA_ENTRY_POINT, FALSE, pErrorCode);
    703         }
    704         return gCommonICUDataArray[commonDataIndex];
    705     }
    706 
    707 
    708     /* request is NOT for ICU Data.  */
    709 
    710     /* Find the base name portion of the supplied path.   */
    711     /*   inBasename will be left pointing somewhere within the original path string.      */
    712     inBasename = findBasename(path);
    713 #ifdef UDATA_DEBUG
    714     fprintf(stderr, "inBasename = %s\n", inBasename);
    715 #endif
    716 
    717     if(*inBasename==0) {
    718         /* no basename.     This will happen if the original path was a directory name,   */
    719         /*    like  "a/b/c/".   (Fallback to separate files will still work.)             */
    720 #ifdef UDATA_DEBUG
    721         fprintf(stderr, "ocd: no basename in %s, bailing.\n", path);
    722 #endif
    723         *pErrorCode=U_FILE_ACCESS_ERROR;
    724         return NULL;
    725     }
    726 
    727    /* Is the requested common data file already open and cached?                     */
    728    /*   Note that the cache is keyed by the base name only.  The rest of the path,   */
    729    /*     if any, is not considered.                                                 */
    730    {
    731         UDataMemory  *dataToReturn = udata_findCachedData(inBasename);
    732         if (dataToReturn != NULL) {
    733             return dataToReturn;
    734         }
    735     }
    736 
    737     /* Requested item is not in the cache.
    738      * Hunt it down, trying all the path locations
    739      */
    740 
    741     UDataPathIterator iter(u_getDataDirectory(), inBasename, path, ".dat", TRUE, pErrorCode);
    742 
    743     while((UDataMemory_isLoaded(&tData)==FALSE) && (pathBuffer = iter.next(pErrorCode)) != NULL)
    744     {
    745 #ifdef UDATA_DEBUG
    746         fprintf(stderr, "ocd: trying path %s - ", pathBuffer);
    747 #endif
    748         uprv_mapFile(&tData, pathBuffer);
    749 #ifdef UDATA_DEBUG
    750         fprintf(stderr, "%s\n", UDataMemory_isLoaded(&tData)?"LOADED":"not loaded");
    751 #endif
    752     }
    753 
    754 #if defined(OS390_STUBDATA) && defined(OS390BATCH)
    755     if (!UDataMemory_isLoaded(&tData)) {
    756         char ourPathBuffer[1024];
    757         /* One more chance, for extendCommonData() */
    758         uprv_strncpy(ourPathBuffer, path, 1019);
    759         ourPathBuffer[1019]=0;
    760         uprv_strcat(ourPathBuffer, ".dat");
    761         uprv_mapFile(&tData, ourPathBuffer);
    762     }
    763 #endif
    764 
    765     if (!UDataMemory_isLoaded(&tData)) {
    766         /* no common data */
    767         *pErrorCode=U_FILE_ACCESS_ERROR;
    768         return NULL;
    769     }
    770 
    771     /* we have mapped a file, check its header */
    772     udata_checkCommonData(&tData, pErrorCode);
    773 
    774 
    775     /* Cache the UDataMemory struct for this .dat file,
    776      *   so we won't need to hunt it down and map it again next time
    777      *   something is needed from it.                */
    778     return udata_cacheDataItem(inBasename, &tData, pErrorCode);
    779 }
    780 
    781 
    782 /*----------------------------------------------------------------------*
    783  *                                                                      *
    784  *   extendICUData   If the full set of ICU data was not loaded at      *
    785  *                   program startup, load it now.  This function will  *
    786  *                   be called when the lookup of an ICU data item in   *
    787  *                   the common ICU data fails.                         *
    788  *                                                                      *
    789  *                   return true if new data is loaded, false otherwise.*
    790  *                                                                      *
    791  *----------------------------------------------------------------------*/
    792 static UBool extendICUData(UErrorCode *pErr)
    793 {
    794     UDataMemory   *pData;
    795     UDataMemory   copyPData;
    796     UBool         didUpdate = FALSE;
    797 
    798     /*
    799      * There is a chance for a race condition here.
    800      * Normally, ICU data is loaded from a DLL or via mmap() and
    801      * setCommonICUData() will detect if the same address is set twice.
    802      * If ICU is built with data loading via fread() then the address will
    803      * be different each time the common data is loaded and we may add
    804      * multiple copies of the data.
    805      * In this case, use a mutex to prevent the race.
    806      * Use a specific mutex to avoid nested locks of the global mutex.
    807      */
    808 #if MAP_IMPLEMENTATION==MAP_STDIO
    809     static UMutex extendICUDataMutex = U_MUTEX_INITIALIZER;
    810     umtx_lock(&extendICUDataMutex);
    811 #endif
    812     if(!gHaveTriedToLoadCommonData) {
    813         /* See if we can explicitly open a .dat file for the ICUData. */
    814         pData = openCommonData(
    815                    U_ICUDATA_NAME,            /*  "icudt20l" , for example.          */
    816                    -1,                        /*  Pretend we're not opening ICUData  */
    817                    pErr);
    818 
    819         /* How about if there is no pData, eh... */
    820 
    821        UDataMemory_init(&copyPData);
    822        if(pData != NULL) {
    823           UDatamemory_assign(&copyPData, pData);
    824           copyPData.map = 0;              /* The mapping for this data is owned by the hash table */
    825           copyPData.mapAddr = 0;          /*   which will unmap it when ICU is shut down.         */
    826                                           /* CommonICUData is also unmapped when ICU is shut down.*/
    827                                           /* To avoid unmapping the data twice, zero out the map  */
    828                                           /*   fields in the UDataMemory that we're assigning     */
    829                                           /*   to CommonICUData.                                  */
    830 
    831           didUpdate = /* no longer using this result */
    832               setCommonICUData(&copyPData,/*  The new common data.                                */
    833                        FALSE,             /*  No warnings if write didn't happen                  */
    834                        pErr);             /*  setCommonICUData honors errors; NOP if error set    */
    835         }
    836 
    837         gHaveTriedToLoadCommonData = TRUE;
    838     }
    839 
    840     didUpdate = findCommonICUDataByName(U_ICUDATA_NAME);  /* Return 'true' when a racing writes out the extended                        */
    841                                                           /* data after another thread has failed to see it (in openCommonData), so     */
    842                                                           /* extended data can be examined.                                             */
    843                                                           /* Also handles a race through here before gHaveTriedToLoadCommonData is set. */
    844 
    845 #if MAP_IMPLEMENTATION==MAP_STDIO
    846     umtx_unlock(&extendICUDataMutex);
    847 #endif
    848     return didUpdate;               /* Return true if ICUData pointer was updated.   */
    849                                     /*   (Could potentialy have been done by another thread racing */
    850                                     /*   us through here, but that's fine, we still return true    */
    851                                     /*   so that current thread will also examine extended data.   */
    852 }
    853 
    854 /*----------------------------------------------------------------------*
    855  *                                                                      *
    856  *   udata_setCommonData                                                *
    857  *                                                                      *
    858  *----------------------------------------------------------------------*/
    859 U_CAPI void U_EXPORT2
    860 udata_setCommonData(const void *data, UErrorCode *pErrorCode) {
    861     UDataMemory dataMemory;
    862 
    863     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
    864         return;
    865     }
    866 
    867     if(data==NULL) {
    868         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
    869         return;
    870     }
    871 
    872     /* set the data pointer and test for validity */
    873     UDataMemory_init(&dataMemory);
    874     UDataMemory_setData(&dataMemory, data);
    875     udata_checkCommonData(&dataMemory, pErrorCode);
    876     if (U_FAILURE(*pErrorCode)) {return;}
    877 
    878     /* we have good data */
    879     /* Set it up as the ICU Common Data.  */
    880     setCommonICUData(&dataMemory, TRUE, pErrorCode);
    881 }
    882 
    883 /*---------------------------------------------------------------------------
    884  *
    885  *  udata_setAppData
    886  *
    887  *---------------------------------------------------------------------------- */
    888 U_CAPI void U_EXPORT2
    889 udata_setAppData(const char *path, const void *data, UErrorCode *err)
    890 {
    891     UDataMemory     udm;
    892 
    893     if(err==NULL || U_FAILURE(*err)) {
    894         return;
    895     }
    896     if(data==NULL) {
    897         *err=U_ILLEGAL_ARGUMENT_ERROR;
    898         return;
    899     }
    900 
    901     UDataMemory_init(&udm);
    902     UDataMemory_setData(&udm, data);
    903     udata_checkCommonData(&udm, err);
    904     udata_cacheDataItem(path, &udm, err);
    905 }
    906 
    907 /*----------------------------------------------------------------------------*
    908  *                                                                            *
    909  *  checkDataItem     Given a freshly located/loaded data item, either        *
    910  *                    an entry in a common file or a separately loaded file,  *
    911  *                    sanity check its header, and see if the data is         *
    912  *                    acceptable to the app.                                  *
    913  *                    If the data is good, create and return a UDataMemory    *
    914  *                    object that can be returned to the application.         *
    915  *                    Return NULL on any sort of failure.                     *
    916  *                                                                            *
    917  *----------------------------------------------------------------------------*/
    918 static UDataMemory *
    919 checkDataItem
    920 (
    921  const DataHeader         *pHeader,         /* The data item to be checked.                */
    922  UDataMemoryIsAcceptable  *isAcceptable,    /* App's call-back function                    */
    923  void                     *context,         /*   pass-thru param for above.                */
    924  const char               *type,            /*   pass-thru param for above.                */
    925  const char               *name,            /*   pass-thru param for above.                */
    926  UErrorCode               *nonFatalErr,     /* Error code if this data was not acceptable  */
    927                                             /*   but openChoice should continue with       */
    928                                             /*   trying to get data from fallback path.    */
    929  UErrorCode               *fatalErr         /* Bad error, caller should return immediately */
    930  )
    931 {
    932     UDataMemory  *rDataMem = NULL;          /* the new UDataMemory, to be returned.        */
    933 
    934     if (U_FAILURE(*fatalErr)) {
    935         return NULL;
    936     }
    937 
    938     if(pHeader->dataHeader.magic1==0xda &&
    939         pHeader->dataHeader.magic2==0x27 &&
    940         (isAcceptable==NULL || isAcceptable(context, type, name, &pHeader->info))
    941     ) {
    942         rDataMem=UDataMemory_createNewInstance(fatalErr);
    943         if (U_FAILURE(*fatalErr)) {
    944             return NULL;
    945         }
    946         rDataMem->pHeader = pHeader;
    947     } else {
    948         /* the data is not acceptable, look further */
    949         /* If we eventually find something good, this errorcode will be */
    950         /*    cleared out.                                              */
    951         *nonFatalErr=U_INVALID_FORMAT_ERROR;
    952     }
    953     return rDataMem;
    954 }
    955 
    956 /**
    957  * @return 0 if not loaded, 1 if loaded or err
    958  */
    959 static UDataMemory *doLoadFromIndividualFiles(const char *pkgName,
    960         const char *dataPath, const char *tocEntryPathSuffix,
    961             /* following arguments are the same as doOpenChoice itself */
    962             const char *path, const char *type, const char *name,
    963              UDataMemoryIsAcceptable *isAcceptable, void *context,
    964              UErrorCode *subErrorCode,
    965              UErrorCode *pErrorCode)
    966 {
    967     const char         *pathBuffer;
    968     UDataMemory         dataMemory;
    969     UDataMemory *pEntryData;
    970 
    971     /* look in ind. files: package\nam.typ  ========================= */
    972     /* init path iterator for individual files */
    973     UDataPathIterator iter(dataPath, pkgName, path, tocEntryPathSuffix, FALSE, pErrorCode);
    974 
    975     while((pathBuffer = iter.next(pErrorCode)))
    976     {
    977 #ifdef UDATA_DEBUG
    978         fprintf(stderr, "UDATA: trying individual file %s\n", pathBuffer);
    979 #endif
    980         if(uprv_mapFile(&dataMemory, pathBuffer))
    981         {
    982             pEntryData = checkDataItem(dataMemory.pHeader, isAcceptable, context, type, name, subErrorCode, pErrorCode);
    983             if (pEntryData != NULL) {
    984                 /* Data is good.
    985                 *  Hand off ownership of the backing memory to the user's UDataMemory.
    986                 *  and return it.   */
    987                 pEntryData->mapAddr = dataMemory.mapAddr;
    988                 pEntryData->map     = dataMemory.map;
    989 
    990 #ifdef UDATA_DEBUG
    991                 fprintf(stderr, "** Mapped file: %s\n", pathBuffer);
    992 #endif
    993                 return pEntryData;
    994             }
    995 
    996             /* the data is not acceptable, or some error occured.  Either way, unmap the memory */
    997             udata_close(&dataMemory);
    998 
    999             /* If we had a nasty error, bail out completely.  */
   1000             if (U_FAILURE(*pErrorCode)) {
   1001                 return NULL;
   1002             }
   1003 
   1004             /* Otherwise remember that we found data but didn't like it for some reason  */
   1005             *subErrorCode=U_INVALID_FORMAT_ERROR;
   1006         }
   1007 #ifdef UDATA_DEBUG
   1008         fprintf(stderr, "%s\n", UDataMemory_isLoaded(&dataMemory)?"LOADED":"not loaded");
   1009 #endif
   1010     }
   1011     return NULL;
   1012 }
   1013 
   1014 /**
   1015  * @return 0 if not loaded, 1 if loaded or err
   1016  */
   1017 static UDataMemory *doLoadFromCommonData(UBool isICUData, const char * /*pkgName*/,
   1018         const char * /*dataPath*/, const char * /*tocEntryPathSuffix*/, const char *tocEntryName,
   1019             /* following arguments are the same as doOpenChoice itself */
   1020             const char *path, const char *type, const char *name,
   1021              UDataMemoryIsAcceptable *isAcceptable, void *context,
   1022              UErrorCode *subErrorCode,
   1023              UErrorCode *pErrorCode)
   1024 {
   1025     UDataMemory        *pEntryData;
   1026     const DataHeader   *pHeader;
   1027     UDataMemory        *pCommonData;
   1028     int32_t            commonDataIndex;
   1029     UBool              checkedExtendedICUData = FALSE;
   1030     /* try to get common data.  The loop is for platforms such as the 390 that do
   1031      *  not initially load the full set of ICU data.  If the lookup of an ICU data item
   1032      *  fails, the full (but slower to load) set is loaded, the and the loop repeats,
   1033      *  trying the lookup again.  Once the full set of ICU data is loaded, the loop wont
   1034      *  repeat because the full set will be checked the first time through.
   1035      *
   1036      *  The loop also handles the fallback to a .dat file if the application linked
   1037      *   to the stub data library rather than a real library.
   1038      */
   1039     for (commonDataIndex = isICUData ? 0 : -1;;) {
   1040         pCommonData=openCommonData(path, commonDataIndex, subErrorCode); /** search for pkg **/
   1041 
   1042         if(U_SUCCESS(*subErrorCode) && pCommonData!=NULL) {
   1043             int32_t length;
   1044 
   1045             /* look up the data piece in the common data */
   1046             pHeader=pCommonData->vFuncs->Lookup(pCommonData, tocEntryName, &length, subErrorCode);
   1047 #ifdef UDATA_DEBUG
   1048             fprintf(stderr, "%s: pHeader=%p - %s\n", tocEntryName, pHeader, u_errorName(*subErrorCode));
   1049 #endif
   1050 
   1051             if(pHeader!=NULL) {
   1052                 pEntryData = checkDataItem(pHeader, isAcceptable, context, type, name, subErrorCode, pErrorCode);
   1053 #ifdef UDATA_DEBUG
   1054                 fprintf(stderr, "pEntryData=%p\n", pEntryData);
   1055 #endif
   1056                 if (U_FAILURE(*pErrorCode)) {
   1057                     return NULL;
   1058                 }
   1059                 if (pEntryData != NULL) {
   1060                     pEntryData->length = length;
   1061                     return pEntryData;
   1062                 }
   1063             }
   1064         }
   1065         /* Data wasn't found.  If we were looking for an ICUData item and there is
   1066          * more data available, load it and try again,
   1067          * otherwise break out of this loop. */
   1068         if (!isICUData) {
   1069             return NULL;
   1070         } else if (pCommonData != NULL) {
   1071             ++commonDataIndex;  /* try the next data package */
   1072         } else if ((!checkedExtendedICUData) && extendICUData(subErrorCode)) {
   1073             checkedExtendedICUData = TRUE;
   1074             /* try this data package slot again: it changed from NULL to non-NULL */
   1075         } else {
   1076             return NULL;
   1077         }
   1078     }
   1079 }
   1080 
   1081 /*
   1082  *  A note on the ownership of Mapped Memory
   1083  *
   1084  *  For common format files, ownership resides with the UDataMemory object
   1085  *    that lives in the cache of opened common data.  These UDataMemorys are private
   1086  *    to the udata implementation, and are never seen directly by users.
   1087  *
   1088  *    The UDataMemory objects returned to users will have the address of some desired
   1089  *    data within the mapped region, but they wont have the mapping info itself, and thus
   1090  *    won't cause anything to be removed from memory when they are closed.
   1091  *
   1092  *  For individual data files, the UDataMemory returned to the user holds the
   1093  *  information necessary to unmap the data on close.  If the user independently
   1094  *  opens the same data file twice, two completely independent mappings will be made.
   1095  *  (There is no cache of opened data items from individual files, only a cache of
   1096  *   opened Common Data files, that is, files containing a collection of data items.)
   1097  *
   1098  *  For common data passed in from the user via udata_setAppData() or
   1099  *  udata_setCommonData(), ownership remains with the user.
   1100  *
   1101  *  UDataMemory objects themselves, as opposed to the memory they describe,
   1102  *  can be anywhere - heap, stack/local or global.
   1103  *  They have a flag to indicate when they're heap allocated and thus
   1104  *  must be deleted when closed.
   1105  */
   1106 
   1107 
   1108 /*----------------------------------------------------------------------------*
   1109  *                                                                            *
   1110  * main data loading functions                                                *
   1111  *                                                                            *
   1112  *----------------------------------------------------------------------------*/
   1113 static UDataMemory *
   1114 doOpenChoice(const char *path, const char *type, const char *name,
   1115              UDataMemoryIsAcceptable *isAcceptable, void *context,
   1116              UErrorCode *pErrorCode)
   1117 {
   1118     UDataMemory         *retVal = NULL;
   1119 
   1120     const char         *dataPath;
   1121 
   1122     int32_t             tocEntrySuffixIndex;
   1123     const char         *tocEntryPathSuffix;
   1124     UErrorCode          subErrorCode=U_ZERO_ERROR;
   1125     const char         *treeChar;
   1126 
   1127     UBool               isICUData = FALSE;
   1128 
   1129 
   1130     /* Is this path ICU data? */
   1131     if(path == NULL ||
   1132        !strcmp(path, U_ICUDATA_ALIAS) ||  /* "ICUDATA" */
   1133        !uprv_strncmp(path, U_ICUDATA_NAME U_TREE_SEPARATOR_STRING, /* "icudt26e-" */
   1134                      uprv_strlen(U_ICUDATA_NAME U_TREE_SEPARATOR_STRING)) ||
   1135        !uprv_strncmp(path, U_ICUDATA_ALIAS U_TREE_SEPARATOR_STRING, /* "ICUDATA-" */
   1136                      uprv_strlen(U_ICUDATA_ALIAS U_TREE_SEPARATOR_STRING))) {
   1137       isICUData = TRUE;
   1138     }
   1139 
   1140 #if (U_FILE_SEP_CHAR != U_FILE_ALT_SEP_CHAR)  /* Windows:  try "foo\bar" and "foo/bar" */
   1141     /* remap from alternate path char to the main one */
   1142     CharString altSepPath;
   1143     if(path) {
   1144         if(uprv_strchr(path,U_FILE_ALT_SEP_CHAR) != NULL) {
   1145             altSepPath.append(path, *pErrorCode);
   1146             char *p;
   1147             while((p=uprv_strchr(altSepPath.data(), U_FILE_ALT_SEP_CHAR))) {
   1148                 *p = U_FILE_SEP_CHAR;
   1149             }
   1150 #if defined (UDATA_DEBUG)
   1151             fprintf(stderr, "Changed path from [%s] to [%s]\n", path, altSepPath.s);
   1152 #endif
   1153             path = altSepPath.data();
   1154         }
   1155     }
   1156 #endif
   1157 
   1158     CharString tocEntryName; /* entry name in tree format. ex:  'icudt28b/coll/ar.res' */
   1159     CharString tocEntryPath; /* entry name in path format. ex:  'icudt28b\\coll\\ar.res' */
   1160 
   1161     CharString pkgName;
   1162     CharString treeName;
   1163 
   1164     /* ======= Set up strings */
   1165     if(path==NULL) {
   1166         pkgName.append(U_ICUDATA_NAME, *pErrorCode);
   1167     } else {
   1168         const char *pkg;
   1169         const char *first;
   1170         pkg = uprv_strrchr(path, U_FILE_SEP_CHAR);
   1171         first = uprv_strchr(path, U_FILE_SEP_CHAR);
   1172         if(uprv_pathIsAbsolute(path) || (pkg != first)) { /* more than one slash in the path- not a tree name */
   1173             /* see if this is an /absolute/path/to/package  path */
   1174             if(pkg) {
   1175                 pkgName.append(pkg+1, *pErrorCode);
   1176             } else {
   1177                 pkgName.append(path, *pErrorCode);
   1178             }
   1179         } else {
   1180             treeChar = uprv_strchr(path, U_TREE_SEPARATOR);
   1181             if(treeChar) {
   1182                 treeName.append(treeChar+1, *pErrorCode); /* following '-' */
   1183                 if(isICUData) {
   1184                     pkgName.append(U_ICUDATA_NAME, *pErrorCode);
   1185                 } else {
   1186                     pkgName.append(path, (int32_t)(treeChar-path), *pErrorCode);
   1187                     if (first == NULL) {
   1188                         /*
   1189                         This user data has no path, but there is a tree name.
   1190                         Look up the correct path from the data cache later.
   1191                         */
   1192                         path = pkgName.data();
   1193                     }
   1194                 }
   1195             } else {
   1196                 if(isICUData) {
   1197                     pkgName.append(U_ICUDATA_NAME, *pErrorCode);
   1198                 } else {
   1199                     pkgName.append(path, *pErrorCode);
   1200                 }
   1201             }
   1202         }
   1203     }
   1204 
   1205 #ifdef UDATA_DEBUG
   1206     fprintf(stderr, " P=%s T=%s\n", pkgName.data(), treeName.data());
   1207 #endif
   1208 
   1209     /* setting up the entry name and file name
   1210      * Make up a full name by appending the type to the supplied
   1211      *  name, assuming that a type was supplied.
   1212      */
   1213 
   1214     /* prepend the package */
   1215     tocEntryName.append(pkgName, *pErrorCode);
   1216     tocEntryPath.append(pkgName, *pErrorCode);
   1217     tocEntrySuffixIndex = tocEntryName.length();
   1218 
   1219     if(!treeName.isEmpty()) {
   1220         tocEntryName.append(U_TREE_ENTRY_SEP_CHAR, *pErrorCode).append(treeName, *pErrorCode);
   1221         tocEntryPath.append(U_FILE_SEP_CHAR, *pErrorCode).append(treeName, *pErrorCode);
   1222     }
   1223 
   1224     tocEntryName.append(U_TREE_ENTRY_SEP_CHAR, *pErrorCode).append(name, *pErrorCode);
   1225     tocEntryPath.append(U_FILE_SEP_CHAR, *pErrorCode).append(name, *pErrorCode);
   1226     if(type!=NULL && *type!=0) {
   1227         tocEntryName.append(".", *pErrorCode).append(type, *pErrorCode);
   1228         tocEntryPath.append(".", *pErrorCode).append(type, *pErrorCode);
   1229     }
   1230     tocEntryPathSuffix = tocEntryPath.data()+tocEntrySuffixIndex; /* suffix starts here */
   1231 
   1232 #ifdef UDATA_DEBUG
   1233     fprintf(stderr, " tocEntryName = %s\n", tocEntryName.data());
   1234     fprintf(stderr, " tocEntryPath = %s\n", tocEntryName.data());
   1235 #endif
   1236 
   1237     if(path == NULL) {
   1238         path = COMMON_DATA_NAME; /* "icudt26e" */
   1239     }
   1240 
   1241     /************************ Begin loop looking for ind. files ***************/
   1242 #ifdef UDATA_DEBUG
   1243     fprintf(stderr, "IND: inBasename = %s, pkg=%s\n", "(n/a)", packageNameFromPath(path));
   1244 #endif
   1245 
   1246     /* End of dealing with a null basename */
   1247     dataPath = u_getDataDirectory();
   1248 
   1249     /****    COMMON PACKAGE  - only if packages are first. */
   1250     if(gDataFileAccess == UDATA_PACKAGES_FIRST) {
   1251 #ifdef UDATA_DEBUG
   1252         fprintf(stderr, "Trying packages (UDATA_PACKAGES_FIRST)\n");
   1253 #endif
   1254         /* #2 */
   1255         retVal = doLoadFromCommonData(isICUData,
   1256                             pkgName.data(), dataPath, tocEntryPathSuffix, tocEntryName.data(),
   1257                             path, type, name, isAcceptable, context, &subErrorCode, pErrorCode);
   1258         if((retVal != NULL) || U_FAILURE(*pErrorCode)) {
   1259             return retVal;
   1260         }
   1261     }
   1262 
   1263     /****    INDIVIDUAL FILES  */
   1264     if((gDataFileAccess==UDATA_PACKAGES_FIRST) ||
   1265        (gDataFileAccess==UDATA_FILES_FIRST)) {
   1266 #ifdef UDATA_DEBUG
   1267         fprintf(stderr, "Trying individual files\n");
   1268 #endif
   1269         /* Check to make sure that there is a dataPath to iterate over */
   1270         if ((dataPath && *dataPath) || !isICUData) {
   1271             retVal = doLoadFromIndividualFiles(pkgName.data(), dataPath, tocEntryPathSuffix,
   1272                             path, type, name, isAcceptable, context, &subErrorCode, pErrorCode);
   1273             if((retVal != NULL) || U_FAILURE(*pErrorCode)) {
   1274                 return retVal;
   1275             }
   1276         }
   1277     }
   1278 
   1279     /****    COMMON PACKAGE  */
   1280     if((gDataFileAccess==UDATA_ONLY_PACKAGES) ||
   1281        (gDataFileAccess==UDATA_FILES_FIRST)) {
   1282 #ifdef UDATA_DEBUG
   1283         fprintf(stderr, "Trying packages (UDATA_ONLY_PACKAGES || UDATA_FILES_FIRST)\n");
   1284 #endif
   1285         retVal = doLoadFromCommonData(isICUData,
   1286                             pkgName.data(), dataPath, tocEntryPathSuffix, tocEntryName.data(),
   1287                             path, type, name, isAcceptable, context, &subErrorCode, pErrorCode);
   1288         if((retVal != NULL) || U_FAILURE(*pErrorCode)) {
   1289             return retVal;
   1290         }
   1291     }
   1292 
   1293     /* Load from DLL.  If we haven't attempted package load, we also haven't had any chance to
   1294         try a DLL (static or setCommonData/etc)  load.
   1295          If we ever have a "UDATA_ONLY_FILES", add it to the or list here.  */
   1296     if(gDataFileAccess==UDATA_NO_FILES) {
   1297 #ifdef UDATA_DEBUG
   1298         fprintf(stderr, "Trying common data (UDATA_NO_FILES)\n");
   1299 #endif
   1300         retVal = doLoadFromCommonData(isICUData,
   1301                             pkgName.data(), "", tocEntryPathSuffix, tocEntryName.data(),
   1302                             path, type, name, isAcceptable, context, &subErrorCode, pErrorCode);
   1303         if((retVal != NULL) || U_FAILURE(*pErrorCode)) {
   1304             return retVal;
   1305         }
   1306     }
   1307 
   1308     /* data not found */
   1309     if(U_SUCCESS(*pErrorCode)) {
   1310         if(U_SUCCESS(subErrorCode)) {
   1311             /* file not found */
   1312             *pErrorCode=U_FILE_ACCESS_ERROR;
   1313         } else {
   1314             /* entry point not found or rejected */
   1315             *pErrorCode=subErrorCode;
   1316         }
   1317     }
   1318     return retVal;
   1319 }
   1320 
   1321 
   1322 
   1323 /* API ---------------------------------------------------------------------- */
   1324 
   1325 U_CAPI UDataMemory * U_EXPORT2
   1326 udata_open(const char *path, const char *type, const char *name,
   1327            UErrorCode *pErrorCode) {
   1328 #ifdef UDATA_DEBUG
   1329   fprintf(stderr, "udata_open(): Opening: %s : %s . %s\n", (path?path:"NULL"), name, type);
   1330     fflush(stderr);
   1331 #endif
   1332 
   1333     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   1334         return NULL;
   1335     } else if(name==NULL || *name==0) {
   1336         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1337         return NULL;
   1338     } else {
   1339         return doOpenChoice(path, type, name, NULL, NULL, pErrorCode);
   1340     }
   1341 }
   1342 
   1343 
   1344 
   1345 U_CAPI UDataMemory * U_EXPORT2
   1346 udata_openChoice(const char *path, const char *type, const char *name,
   1347                  UDataMemoryIsAcceptable *isAcceptable, void *context,
   1348                  UErrorCode *pErrorCode) {
   1349 #ifdef UDATA_DEBUG
   1350   fprintf(stderr, "udata_openChoice(): Opening: %s : %s . %s\n", (path?path:"NULL"), name, type);
   1351 #endif
   1352 
   1353     if(pErrorCode==NULL || U_FAILURE(*pErrorCode)) {
   1354         return NULL;
   1355     } else if(name==NULL || *name==0 || isAcceptable==NULL) {
   1356         *pErrorCode=U_ILLEGAL_ARGUMENT_ERROR;
   1357         return NULL;
   1358     } else {
   1359         return doOpenChoice(path, type, name, isAcceptable, context, pErrorCode);
   1360     }
   1361 }
   1362 
   1363 
   1364 
   1365 U_CAPI void U_EXPORT2
   1366 udata_getInfo(UDataMemory *pData, UDataInfo *pInfo) {
   1367     if(pInfo!=NULL) {
   1368         if(pData!=NULL && pData->pHeader!=NULL) {
   1369             const UDataInfo *info=&pData->pHeader->info;
   1370             uint16_t dataInfoSize=udata_getInfoSize(info);
   1371             if(pInfo->size>dataInfoSize) {
   1372                 pInfo->size=dataInfoSize;
   1373             }
   1374             uprv_memcpy((uint16_t *)pInfo+1, (const uint16_t *)info+1, pInfo->size-2);
   1375             if(info->isBigEndian!=U_IS_BIG_ENDIAN) {
   1376                 /* opposite endianness */
   1377                 uint16_t x=info->reservedWord;
   1378                 pInfo->reservedWord=(uint16_t)((x<<8)|(x>>8));
   1379             }
   1380         } else {
   1381             pInfo->size=0;
   1382         }
   1383     }
   1384 }
   1385 
   1386 
   1387 U_CAPI void U_EXPORT2 udata_setFileAccess(UDataFileAccess access, UErrorCode * /*status*/)
   1388 {
   1389     gDataFileAccess = access;
   1390 }
   1391