intl/icu/source/common/unicode/udata.h

Wed, 31 Dec 2014 06:09:35 +0100

author
Michael Schloh von Bennewitz <michael@schloh.com>
date
Wed, 31 Dec 2014 06:09:35 +0100
changeset 0
6474c204b198
permissions
-rw-r--r--

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /*
     2 ******************************************************************************
     3 *
     4 *   Copyright (C) 1999-2012, International Business Machines
     5 *   Corporation and others.  All Rights Reserved.
     6 *
     7 ******************************************************************************
     8 *   file name:  udata.h
     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 */
    17 #ifndef __UDATA_H__
    18 #define __UDATA_H__
    20 #include "unicode/utypes.h"
    21 #include "unicode/localpointer.h"
    23 U_CDECL_BEGIN
    25 /**
    26  * \file
    27  * \brief C API: Data loading interface
    28  *
    29  * <h2>Information about data loading interface</h2>
    30  *
    31  * This API is used to find and efficiently load data for ICU and applications
    32  * using ICU. It provides an abstract interface that specifies a data type and
    33  * name to find and load the data. Normally this API is used by other ICU APIs
    34  * to load required data out of the ICU data library, but it can be used to
    35  * load data out of other places.
    36  *
    37  * See the User Guide Data Management chapter.
    38  */
    40 #ifndef U_HIDE_INTERNAL_API
    41 /**
    42  * Character used to separate package names from tree names 
    43  * @internal ICU 3.0
    44  */
    45 #define U_TREE_SEPARATOR '-'
    47 /**
    48  * String used to separate package names from tree names 
    49  * @internal ICU 3.0
    50  */
    51 #define U_TREE_SEPARATOR_STRING "-"
    53 /**
    54  * Character used to separate parts of entry names
    55  * @internal ICU 3.0
    56  */
    57 #define U_TREE_ENTRY_SEP_CHAR '/'
    59 /**
    60  * String used to separate parts of entry names
    61  * @internal ICU 3.0
    62  */
    63 #define U_TREE_ENTRY_SEP_STRING "/"
    65 /**
    66  * Alias for standard ICU data 
    67  * @internal ICU 3.0
    68  */
    69 #define U_ICUDATA_ALIAS "ICUDATA"
    71 #endif /* U_HIDE_INTERNAL_API */
    73 /**
    74  * UDataInfo contains the properties about the requested data.
    75  * This is meta data.
    76  *
    77  * <p>This structure may grow in the future, indicated by the
    78  * <code>size</code> field.</p>
    79  *
    80  * <p>The platform data property fields help determine if a data
    81  * file can be efficiently used on a given machine.
    82  * The particular fields are of importance only if the data
    83  * is affected by the properties - if there is integer data
    84  * with word sizes > 1 byte, char* text, or UChar* text.</p>
    85  *
    86  * <p>The implementation for the <code>udata_open[Choice]()</code>
    87  * functions may reject data based on the value in <code>isBigEndian</code>.
    88  * No other field is used by the <code>udata</code> API implementation.</p>
    89  *
    90  * <p>The <code>dataFormat</code> may be used to identify
    91  * the kind of data, e.g. a converter table.</p>
    92  *
    93  * <p>The <code>formatVersion</code> field should be used to
    94  * make sure that the format can be interpreted.
    95  * I may be a good idea to check only for the one or two highest
    96  * of the version elements to allow the data memory to
    97  * get more or somewhat rearranged contents, for as long
    98  * as the using code can still interpret the older contents.</p>
    99  *
   100  * <p>The <code>dataVersion</code> field is intended to be a
   101  * common place to store the source version of the data;
   102  * for data from the Unicode character database, this could
   103  * reflect the Unicode version.</p>
   104  * @stable ICU 2.0
   105  */
   106 typedef struct {
   107     /** sizeof(UDataInfo)
   108      *  @stable ICU 2.0 */
   109     uint16_t size;
   111     /** unused, set to 0 
   112      *  @stable ICU 2.0*/
   113     uint16_t reservedWord;
   115     /* platform data properties */
   116     /** 0 for little-endian machine, 1 for big-endian
   117      *  @stable ICU 2.0 */
   118     uint8_t isBigEndian;
   120     /** see U_CHARSET_FAMILY values in utypes.h 
   121      *  @stable ICU 2.0*/
   122     uint8_t charsetFamily;
   124     /** sizeof(UChar), one of { 1, 2, 4 } 
   125      *  @stable ICU 2.0*/
   126     uint8_t sizeofUChar;
   128     /** unused, set to 0 
   129      *  @stable ICU 2.0*/
   130     uint8_t reservedByte;
   132     /** data format identifier 
   133      *  @stable ICU 2.0*/
   134     uint8_t dataFormat[4];
   136     /** versions: [0] major [1] minor [2] milli [3] micro 
   137      *  @stable ICU 2.0*/
   138     uint8_t formatVersion[4];
   140     /** versions: [0] major [1] minor [2] milli [3] micro 
   141      *  @stable ICU 2.0*/
   142     uint8_t dataVersion[4];
   143 } UDataInfo;
   145 /* API for reading data -----------------------------------------------------*/
   147 /**
   148  * Forward declaration of the data memory type.
   149  * @stable ICU 2.0
   150  */
   151 typedef struct UDataMemory UDataMemory;
   153 /**
   154  * Callback function for udata_openChoice().
   155  * @param context parameter passed into <code>udata_openChoice()</code>.
   156  * @param type The type of the data as passed into <code>udata_openChoice()</code>.
   157  *             It may be <code>NULL</code>.
   158  * @param name The name of the data as passed into <code>udata_openChoice()</code>.
   159  * @param pInfo A pointer to the <code>UDataInfo</code> structure
   160  *              of data that has been loaded and will be returned
   161  *              by <code>udata_openChoice()</code> if this function
   162  *              returns <code>TRUE</code>.
   163  * @return TRUE if the current data memory is acceptable
   164  * @stable ICU 2.0
   165  */
   166 typedef UBool U_CALLCONV
   167 UDataMemoryIsAcceptable(void *context,
   168                         const char *type, const char *name,
   169                         const UDataInfo *pInfo);
   172 /**
   173  * Convenience function.
   174  * This function works the same as <code>udata_openChoice</code>
   175  * except that any data that matches the type and name
   176  * is assumed to be acceptable.
   177  * @param path Specifies an absolute path and/or a basename for the
   178  *             finding of the data in the file system.
   179  *             <code>NULL</code> for ICU data.
   180  * @param type A string that specifies the type of data to be loaded.
   181  *             For example, resource bundles are loaded with type "res",
   182  *             conversion tables with type "cnv".
   183  *             This may be <code>NULL</code> or empty.
   184  * @param name A string that specifies the name of the data.
   185  * @param pErrorCode An ICU UErrorCode parameter. It must not be <code>NULL</code>.
   186  * @return A pointer (handle) to a data memory object, or <code>NULL</code>
   187  *         if an error occurs. Call <code>udata_getMemory()</code>
   188  *         to get a pointer to the actual data.
   189  *
   190  * @see udata_openChoice
   191  * @stable ICU 2.0
   192  */
   193 U_STABLE UDataMemory * U_EXPORT2
   194 udata_open(const char *path, const char *type, const char *name,
   195            UErrorCode *pErrorCode);
   197 /**
   198  * Data loading function.
   199  * This function is used to find and load efficiently data for
   200  * ICU and applications using ICU.
   201  * It provides an abstract interface that allows to specify a data
   202  * type and name to find and load the data.
   203  *
   204  * <p>The implementation depends on platform properties and user preferences
   205  * and may involve loading shared libraries (DLLs), mapping
   206  * files into memory, or fopen()/fread() files.
   207  * It may also involve using static memory or database queries etc.
   208  * Several or all data items may be combined into one entity
   209  * (DLL, memory-mappable file).</p>
   210  *
   211  * <p>The data is always preceded by a header that includes
   212  * a <code>UDataInfo</code> structure.
   213  * The caller's <code>isAcceptable()</code> function is called to make
   214  * sure that the data is useful. It may be called several times if it
   215  * rejects the data and there is more than one location with data
   216  * matching the type and name.</p>
   217  *
   218  * <p>If <code>path==NULL</code>, then ICU data is loaded.
   219  * Otherwise, it is separated into a basename and a basename-less directory string.
   220  * The basename is used as the data package name, and the directory is
   221  * logically prepended to the ICU data directory string.</p>
   222  *
   223  * <p>For details about ICU data loading see the User Guide
   224  * Data Management chapter. (http://icu-project.org/userguide/icudata.html)</p>
   225  *
   226  * @param path Specifies an absolute path and/or a basename for the
   227  *             finding of the data in the file system.
   228  *             <code>NULL</code> for ICU data.
   229  * @param type A string that specifies the type of data to be loaded.
   230  *             For example, resource bundles are loaded with type "res",
   231  *             conversion tables with type "cnv".
   232  *             This may be <code>NULL</code> or empty.
   233  * @param name A string that specifies the name of the data.
   234  * @param isAcceptable This function is called to verify that loaded data
   235  *                     is useful for the client code. If it returns FALSE
   236  *                     for all data items, then <code>udata_openChoice()</code>
   237  *                     will return with an error.
   238  * @param context Arbitrary parameter to be passed into isAcceptable.
   239  * @param pErrorCode An ICU UErrorCode parameter. It must not be <code>NULL</code>.
   240  * @return A pointer (handle) to a data memory object, or <code>NULL</code>
   241  *         if an error occurs. Call <code>udata_getMemory()</code>
   242  *         to get a pointer to the actual data.
   243  * @stable ICU 2.0
   244  */
   245 U_STABLE UDataMemory * U_EXPORT2
   246 udata_openChoice(const char *path, const char *type, const char *name,
   247                  UDataMemoryIsAcceptable *isAcceptable, void *context,
   248                  UErrorCode *pErrorCode);
   250 /**
   251  * Close the data memory.
   252  * This function must be called to allow the system to
   253  * release resources associated with this data memory.
   254  * @param pData The pointer to data memory object
   255  * @stable ICU 2.0
   256  */
   257 U_STABLE void U_EXPORT2
   258 udata_close(UDataMemory *pData);
   260 #if U_SHOW_CPLUSPLUS_API
   262 U_NAMESPACE_BEGIN
   264 /**
   265  * \class LocalUDataMemoryPointer
   266  * "Smart pointer" class, closes a UDataMemory via udata_close().
   267  * For most methods see the LocalPointerBase base class.
   268  *
   269  * @see LocalPointerBase
   270  * @see LocalPointer
   271  * @stable ICU 4.4
   272  */
   273 U_DEFINE_LOCAL_OPEN_POINTER(LocalUDataMemoryPointer, UDataMemory, udata_close);
   275 U_NAMESPACE_END
   277 #endif
   279 /**
   280  * Get the pointer to the actual data inside the data memory.
   281  * The data is read-only.
   282  * @param pData The pointer to data memory object
   283  * @stable ICU 2.0
   284  */
   285 U_STABLE const void * U_EXPORT2
   286 udata_getMemory(UDataMemory *pData);
   288 /**
   289  * Get the information from the data memory header.
   290  * This allows to get access to the header containing
   291  * platform data properties etc. which is not part of
   292  * the data itself and can therefore not be accessed
   293  * via the pointer that <code>udata_getMemory()</code> returns.
   294  *
   295  * @param pData pointer to the data memory object
   296  * @param pInfo pointer to a UDataInfo object;
   297  *              its <code>size</code> field must be set correctly,
   298  *              typically to <code>sizeof(UDataInfo)</code>.
   299  *
   300  * <code>*pInfo</code> will be filled with the UDataInfo structure
   301  * in the data memory object. If this structure is smaller than
   302  * <code>pInfo->size</code>, then the <code>size</code> will be
   303  * adjusted and only part of the structure will be filled.
   304  * @stable ICU 2.0
   305  */
   306 U_STABLE void U_EXPORT2
   307 udata_getInfo(UDataMemory *pData, UDataInfo *pInfo);
   309 /**
   310  * This function bypasses the normal ICU data loading process and
   311  * allows you to force ICU's system data to come out of a user-specified
   312  * area in memory.
   313  *
   314  * The format of this data is that of the icu common data file, as is
   315  * generated by the pkgdata tool with mode=common or mode=dll.
   316  * You can read in a whole common mode file and pass the address to the start of the
   317  * data, or (with the appropriate link options) pass in the pointer to
   318  * the data that has been loaded from a dll by the operating system,
   319  * as shown in this code:
   320  *
   321  *       extern const char U_IMPORT U_ICUDATA_ENTRY_POINT [];
   322  *        // U_ICUDATA_ENTRY_POINT is same as entry point specified to pkgdata tool
   323  *       UErrorCode  status = U_ZERO_ERROR;
   324  *
   325  *       udata_setCommonData(&U_ICUDATA_ENTRY_POINT, &status);
   326  *
   327  * It is important that the declaration be as above. The entry point
   328  * must not be declared as an extern void*.
   329  *
   330  * Starting with ICU 4.4, it is possible to set several data packages,
   331  * one per call to this function.
   332  * udata_open() will look for data in the multiple data packages in the order
   333  * in which they were set.
   334  * The position of the linked-in or default-name ICU .data package in the
   335  * search list depends on when the first data item is loaded that is not contained
   336  * in the already explicitly set packages.
   337  * If data was loaded implicitly before the first call to this function
   338  * (for example, via opening a converter, constructing a UnicodeString
   339  * from default-codepage data, using formatting or collation APIs, etc.),
   340  * then the default data will be first in the list.
   341  *
   342  * This function has no effect on application (non ICU) data.  See udata_setAppData()
   343  * for similar functionality for application data.
   344  *
   345  * @param data pointer to ICU common data
   346  * @param err outgoing error status <code>U_USING_DEFAULT_WARNING, U_UNSUPPORTED_ERROR</code>
   347  * @stable ICU 2.0
   348  */
   349 U_STABLE void U_EXPORT2
   350 udata_setCommonData(const void *data, UErrorCode *err);
   353 /**
   354  * This function bypasses the normal ICU data loading process for application-specific
   355  * data and allows you to force the it to come out of a user-specified
   356  * pointer.
   357  *
   358  * The format of this data is that of the icu common data file, like 'icudt26l.dat'
   359  * or the corresponding shared library (DLL) file.
   360  * The application must read in or otherwise construct an image of the data and then
   361  * pass the address of it to this function.
   362  *
   363  *
   364  * Warning:  setAppData will set a U_USING_DEFAULT_WARNING code if
   365  *           data with the specifed path that has already been opened, or
   366  *           if setAppData with the same path has already been called.
   367  *           Any such calls to setAppData will have no effect.
   368  *
   369  *
   370  * @param packageName the package name by which the application will refer
   371  *             to (open) this data
   372  * @param data pointer to the data
   373  * @param err outgoing error status <code>U_USING_DEFAULT_WARNING, U_UNSUPPORTED_ERROR</code>
   374  * @see udata_setCommonData
   375  * @stable ICU 2.0
   376  */
   377 U_STABLE void U_EXPORT2
   378 udata_setAppData(const char *packageName, const void *data, UErrorCode *err);
   380 /**
   381  * Possible settings for udata_setFileAccess()
   382  * @see udata_setFileAccess
   383  * @stable ICU 3.4
   384  */
   385 typedef enum UDataFileAccess {
   386     /** ICU looks for data in single files first, then in packages. (default) @stable ICU 3.4 */
   387     UDATA_FILES_FIRST,
   388     /** An alias for the default access mode. @stable ICU 3.4 */
   389     UDATA_DEFAULT_ACCESS = UDATA_FILES_FIRST,
   390     /** ICU only loads data from packages, not from single files. @stable ICU 3.4 */
   391     UDATA_ONLY_PACKAGES,
   392     /** ICU loads data from packages first, and only from single files
   393         if the data cannot be found in a package. @stable ICU 3.4 */
   394     UDATA_PACKAGES_FIRST,
   395     /** ICU does not access the file system for data loading. @stable ICU 3.4 */
   396     UDATA_NO_FILES,
   397     /** Number of real UDataFileAccess values. @stable ICU 3.4 */
   398     UDATA_FILE_ACCESS_COUNT
   399 } UDataFileAccess;
   401 /**
   402  * This function may be called to control how ICU loads data. It must be called
   403  * before any ICU data is loaded, including application data loaded with 
   404  * ures/ResourceBundle or udata APIs. This function is not multithread safe.  
   405  * The results of calling it while other threads are loading data are undefined.
   406  * @param access The type of file access to be used
   407  * @param status Error code.
   408  * @see UDataFileAccess
   409  * @stable ICU 3.4 
   410  */
   411 U_STABLE void U_EXPORT2
   412 udata_setFileAccess(UDataFileAccess access, UErrorCode *status);
   414 U_CDECL_END
   416 #endif

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