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diff --git a/intl/icu/source/common/unicode/udata.h b/intl/icu/source/common/unicode/udata.h new file mode 100644 index 0000000000..4cda255010 --- /dev/null +++ b/intl/icu/source/common/unicode/udata.h @@ -0,0 +1,440 @@ +// © 2016 and later: Unicode, Inc. and others. +// License & terms of use: http://www.unicode.org/copyright.html +/* +****************************************************************************** +* +* Copyright (C) 1999-2014, International Business Machines +* Corporation and others. All Rights Reserved. +* +****************************************************************************** +* file name: udata.h +* encoding: UTF-8 +* tab size: 8 (not used) +* indentation:4 +* +* created on: 1999oct25 +* created by: Markus W. Scherer +*/ + +#ifndef __UDATA_H__ +#define __UDATA_H__ + +#include "unicode/utypes.h" + +#if U_SHOW_CPLUSPLUS_API +#include "unicode/localpointer.h" +#endif // U_SHOW_CPLUSPLUS_API + +U_CDECL_BEGIN + +/** + * \file + * \brief C API: Data loading interface + * + * <h2>Information about data loading interface</h2> + * + * This API is used to find and efficiently load data for ICU and applications + * using ICU. It provides an abstract interface that specifies a data type and + * name to find and load the data. Normally this API is used by other ICU APIs + * to load required data out of the ICU data library, but it can be used to + * load data out of other places. + * + * See the User Guide Data Management chapter. + */ + +#ifndef U_HIDE_INTERNAL_API +/** + * Character used to separate package names from tree names + * @internal ICU 3.0 + */ +#define U_TREE_SEPARATOR '-' + +/** + * String used to separate package names from tree names + * @internal ICU 3.0 + */ +#define U_TREE_SEPARATOR_STRING "-" + +/** + * Character used to separate parts of entry names + * @internal ICU 3.0 + */ +#define U_TREE_ENTRY_SEP_CHAR '/' + +/** + * String used to separate parts of entry names + * @internal ICU 3.0 + */ +#define U_TREE_ENTRY_SEP_STRING "/" + +/** + * Alias for standard ICU data + * @internal ICU 3.0 + */ +#define U_ICUDATA_ALIAS "ICUDATA" + +#endif /* U_HIDE_INTERNAL_API */ + +/** + * UDataInfo contains the properties about the requested data. + * This is meta data. + * + * <p>This structure may grow in the future, indicated by the + * <code>size</code> field.</p> + * + * <p>ICU data must be at least 8-aligned, and should be 16-aligned. + * The UDataInfo struct begins 4 bytes after the start of the data item, + * so it is 4-aligned. + * + * <p>The platform data property fields help determine if a data + * file can be efficiently used on a given machine. + * The particular fields are of importance only if the data + * is affected by the properties - if there is integer data + * with word sizes > 1 byte, char* text, or UChar* text.</p> + * + * <p>The implementation for the <code>udata_open[Choice]()</code> + * functions may reject data based on the value in <code>isBigEndian</code>. + * No other field is used by the <code>udata</code> API implementation.</p> + * + * <p>The <code>dataFormat</code> may be used to identify + * the kind of data, e.g. a converter table.</p> + * + * <p>The <code>formatVersion</code> field should be used to + * make sure that the format can be interpreted. + * It may be a good idea to check only for the one or two highest + * of the version elements to allow the data memory to + * get more or somewhat rearranged contents, for as long + * as the using code can still interpret the older contents.</p> + * + * <p>The <code>dataVersion</code> field is intended to be a + * common place to store the source version of the data; + * for data from the Unicode character database, this could + * reflect the Unicode version.</p> + * + * @stable ICU 2.0 + */ +typedef struct { + /** sizeof(UDataInfo) + * @stable ICU 2.0 */ + uint16_t size; + + /** unused, set to 0 + * @stable ICU 2.0*/ + uint16_t reservedWord; + + /* platform data properties */ + /** 0 for little-endian machine, 1 for big-endian + * @stable ICU 2.0 */ + uint8_t isBigEndian; + + /** see U_CHARSET_FAMILY values in utypes.h + * @stable ICU 2.0*/ + uint8_t charsetFamily; + + /** sizeof(UChar), one of { 1, 2, 4 } + * @stable ICU 2.0*/ + uint8_t sizeofUChar; + + /** unused, set to 0 + * @stable ICU 2.0*/ + uint8_t reservedByte; + + /** data format identifier + * @stable ICU 2.0*/ + uint8_t dataFormat[4]; + + /** versions: [0] major [1] minor [2] milli [3] micro + * @stable ICU 2.0*/ + uint8_t formatVersion[4]; + + /** versions: [0] major [1] minor [2] milli [3] micro + * @stable ICU 2.0*/ + uint8_t dataVersion[4]; +} UDataInfo; + +/* API for reading data -----------------------------------------------------*/ + +/** + * Forward declaration of the data memory type. + * @stable ICU 2.0 + */ +typedef struct UDataMemory UDataMemory; + +/** + * Callback function for udata_openChoice(). + * @param context parameter passed into <code>udata_openChoice()</code>. + * @param type The type of the data as passed into <code>udata_openChoice()</code>. + * It may be <code>NULL</code>. + * @param name The name of the data as passed into <code>udata_openChoice()</code>. + * @param pInfo A pointer to the <code>UDataInfo</code> structure + * of data that has been loaded and will be returned + * by <code>udata_openChoice()</code> if this function + * returns <code>true</code>. + * @return true if the current data memory is acceptable + * @stable ICU 2.0 + */ +typedef UBool U_CALLCONV +UDataMemoryIsAcceptable(void *context, + const char *type, const char *name, + const UDataInfo *pInfo); + + +/** + * Convenience function. + * This function works the same as <code>udata_openChoice</code> + * except that any data that matches the type and name + * is assumed to be acceptable. + * @param path Specifies an absolute path and/or a basename for the + * finding of the data in the file system. + * <code>NULL</code> for ICU data. + * @param type A string that specifies the type of data to be loaded. + * For example, resource bundles are loaded with type "res", + * conversion tables with type "cnv". + * This may be <code>NULL</code> or empty. + * @param name A string that specifies the name of the data. + * @param pErrorCode An ICU UErrorCode parameter. It must not be <code>NULL</code>. + * @return A pointer (handle) to a data memory object, or <code>NULL</code> + * if an error occurs. Call <code>udata_getMemory()</code> + * to get a pointer to the actual data. + * + * @see udata_openChoice + * @stable ICU 2.0 + */ +U_CAPI UDataMemory * U_EXPORT2 +udata_open(const char *path, const char *type, const char *name, + UErrorCode *pErrorCode); + +/** + * Data loading function. + * This function is used to find and load efficiently data for + * ICU and applications using ICU. + * It provides an abstract interface that allows to specify a data + * type and name to find and load the data. + * + * <p>The implementation depends on platform properties and user preferences + * and may involve loading shared libraries (DLLs), mapping + * files into memory, or fopen()/fread() files. + * It may also involve using static memory or database queries etc. + * Several or all data items may be combined into one entity + * (DLL, memory-mappable file).</p> + * + * <p>The data is always preceded by a header that includes + * a <code>UDataInfo</code> structure. + * The caller's <code>isAcceptable()</code> function is called to make + * sure that the data is useful. It may be called several times if it + * rejects the data and there is more than one location with data + * matching the type and name.</p> + * + * <p>If <code>path==NULL</code>, then ICU data is loaded. + * Otherwise, it is separated into a basename and a basename-less directory string. + * The basename is used as the data package name, and the directory is + * logically prepended to the ICU data directory string.</p> + * + * <p>For details about ICU data loading see the User Guide + * Data Management chapter. (https://unicode-org.github.io/icu/userguide/icu_data/)</p> + * + * @param path Specifies an absolute path and/or a basename for the + * finding of the data in the file system. + * <code>NULL</code> for ICU data. + * @param type A string that specifies the type of data to be loaded. + * For example, resource bundles are loaded with type "res", + * conversion tables with type "cnv". + * This may be <code>NULL</code> or empty. + * @param name A string that specifies the name of the data. + * @param isAcceptable This function is called to verify that loaded data + * is useful for the client code. If it returns false + * for all data items, then <code>udata_openChoice()</code> + * will return with an error. + * @param context Arbitrary parameter to be passed into isAcceptable. + * @param pErrorCode An ICU UErrorCode parameter. It must not be <code>NULL</code>. + * @return A pointer (handle) to a data memory object, or <code>NULL</code> + * if an error occurs. Call <code>udata_getMemory()</code> + * to get a pointer to the actual data. + * @stable ICU 2.0 + */ +U_CAPI UDataMemory * U_EXPORT2 +udata_openChoice(const char *path, const char *type, const char *name, + UDataMemoryIsAcceptable *isAcceptable, void *context, + UErrorCode *pErrorCode); + +/** + * Close the data memory. + * This function must be called to allow the system to + * release resources associated with this data memory. + * @param pData The pointer to data memory object + * @stable ICU 2.0 + */ +U_CAPI void U_EXPORT2 +udata_close(UDataMemory *pData); + +/** + * Get the pointer to the actual data inside the data memory. + * The data is read-only. + * + * ICU data must be at least 8-aligned, and should be 16-aligned. + * + * @param pData The pointer to data memory object + * @stable ICU 2.0 + */ +U_CAPI const void * U_EXPORT2 +udata_getMemory(UDataMemory *pData); + +/** + * Get the information from the data memory header. + * This allows to get access to the header containing + * platform data properties etc. which is not part of + * the data itself and can therefore not be accessed + * via the pointer that <code>udata_getMemory()</code> returns. + * + * @param pData pointer to the data memory object + * @param pInfo pointer to a UDataInfo object; + * its <code>size</code> field must be set correctly, + * typically to <code>sizeof(UDataInfo)</code>. + * + * <code>*pInfo</code> will be filled with the UDataInfo structure + * in the data memory object. If this structure is smaller than + * <code>pInfo->size</code>, then the <code>size</code> will be + * adjusted and only part of the structure will be filled. + * @stable ICU 2.0 + */ +U_CAPI void U_EXPORT2 +udata_getInfo(UDataMemory *pData, UDataInfo *pInfo); + +/** + * This function bypasses the normal ICU data loading process and + * allows you to force ICU's system data to come out of a user-specified + * area in memory. + * + * ICU data must be at least 8-aligned, and should be 16-aligned. + * See https://unicode-org.github.io/icu/userguide/icu_data + * + * The format of this data is that of the icu common data file, as is + * generated by the pkgdata tool with mode=common or mode=dll. + * You can read in a whole common mode file and pass the address to the start of the + * data, or (with the appropriate link options) pass in the pointer to + * the data that has been loaded from a dll by the operating system, + * as shown in this code: + * + * extern const char U_IMPORT U_ICUDATA_ENTRY_POINT []; + * // U_ICUDATA_ENTRY_POINT is same as entry point specified to pkgdata tool + * UErrorCode status = U_ZERO_ERROR; + * + * udata_setCommonData(&U_ICUDATA_ENTRY_POINT, &status); + * + * It is important that the declaration be as above. The entry point + * must not be declared as an extern void*. + * + * Starting with ICU 4.4, it is possible to set several data packages, + * one per call to this function. + * udata_open() will look for data in the multiple data packages in the order + * in which they were set. + * The position of the linked-in or default-name ICU .data package in the + * search list depends on when the first data item is loaded that is not contained + * in the already explicitly set packages. + * If data was loaded implicitly before the first call to this function + * (for example, via opening a converter, constructing a UnicodeString + * from default-codepage data, using formatting or collation APIs, etc.), + * then the default data will be first in the list. + * + * This function has no effect on application (non ICU) data. See udata_setAppData() + * for similar functionality for application data. + * + * @param data pointer to ICU common data + * @param err outgoing error status <code>U_USING_DEFAULT_WARNING, U_UNSUPPORTED_ERROR</code> + * @stable ICU 2.0 + */ +U_CAPI void U_EXPORT2 +udata_setCommonData(const void *data, UErrorCode *err); + + +/** + * This function bypasses the normal ICU data loading process for application-specific + * data and allows you to force the it to come out of a user-specified + * pointer. + * + * ICU data must be at least 8-aligned, and should be 16-aligned. + * See https://unicode-org.github.io/icu/userguide/icu_data + * + * The format of this data is that of the icu common data file, like 'icudt26l.dat' + * or the corresponding shared library (DLL) file. + * The application must read in or otherwise construct an image of the data and then + * pass the address of it to this function. + * + * + * Warning: setAppData will set a U_USING_DEFAULT_WARNING code if + * data with the specified path that has already been opened, or + * if setAppData with the same path has already been called. + * Any such calls to setAppData will have no effect. + * + * + * @param packageName the package name by which the application will refer + * to (open) this data + * @param data pointer to the data + * @param err outgoing error status <code>U_USING_DEFAULT_WARNING, U_UNSUPPORTED_ERROR</code> + * @see udata_setCommonData + * @stable ICU 2.0 + */ +U_CAPI void U_EXPORT2 +udata_setAppData(const char *packageName, const void *data, UErrorCode *err); + +/** + * Possible settings for udata_setFileAccess() + * @see udata_setFileAccess + * @stable ICU 3.4 + */ +typedef enum UDataFileAccess { + /** ICU looks for data in single files first, then in packages. (default) @stable ICU 3.4 */ + UDATA_FILES_FIRST, + /** An alias for the default access mode. @stable ICU 3.4 */ + UDATA_DEFAULT_ACCESS = UDATA_FILES_FIRST, + /** ICU only loads data from packages, not from single files. @stable ICU 3.4 */ + UDATA_ONLY_PACKAGES, + /** ICU loads data from packages first, and only from single files + if the data cannot be found in a package. @stable ICU 3.4 */ + UDATA_PACKAGES_FIRST, + /** ICU does not access the file system for data loading. @stable ICU 3.4 */ + UDATA_NO_FILES, +#ifndef U_HIDE_DEPRECATED_API + /** + * Number of real UDataFileAccess values. + * @deprecated ICU 58 The numeric value may change over time, see ICU ticket #12420. + */ + UDATA_FILE_ACCESS_COUNT +#endif // U_HIDE_DEPRECATED_API +} UDataFileAccess; + +/** + * This function may be called to control how ICU loads data. It must be called + * before any ICU data is loaded, including application data loaded with + * ures/ResourceBundle or udata APIs. This function is not multithread safe. + * The results of calling it while other threads are loading data are undefined. + * @param access The type of file access to be used + * @param status Error code. + * @see UDataFileAccess + * @stable ICU 3.4 + */ +U_CAPI void U_EXPORT2 +udata_setFileAccess(UDataFileAccess access, UErrorCode *status); + +U_CDECL_END + +#if U_SHOW_CPLUSPLUS_API + +U_NAMESPACE_BEGIN + +/** + * \class LocalUDataMemoryPointer + * "Smart pointer" class, closes a UDataMemory via udata_close(). + * For most methods see the LocalPointerBase base class. + * + * @see LocalPointerBase + * @see LocalPointer + * @stable ICU 4.4 + */ +U_DEFINE_LOCAL_OPEN_POINTER(LocalUDataMemoryPointer, UDataMemory, udata_close); + +U_NAMESPACE_END + +#endif // U_SHOW_CPLUSPLUS_API + +#endif |