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// © 2016 and later: Unicode, Inc. and others.
// License & terms of use: http://www.unicode.org/copyright.html
/*
**********************************************************************
* Copyright (c) 2003-2004, International Business Machines
* Corporation and others. All Rights Reserved.
**********************************************************************
* Author: Alan Liu
* Created: March 19 2003
* Since: ICU 2.6
**********************************************************************
*/
#ifndef UCAT_H
#define UCAT_H
#include "unicode/utypes.h"
#include "unicode/ures.h"
/**
* \file
* \brief C API: Message Catalog Wrappers
*
* This C API provides look-alike functions that deliberately resemble
* the POSIX catopen, catclose, and catgets functions. The underlying
* implementation is in terms of ICU resource bundles, rather than
* POSIX message catalogs.
*
* The ICU resource bundles obey standard ICU inheritance policies.
* To facilitate this, sets and messages are flattened into one tier.
* This is done by creating resource bundle keys of the form
* <set_num>%<msg_num> where set_num is the set number and msg_num is
* the message number, formatted as decimal strings.
*
* Example: Consider a message catalog containing two sets:
*
* Set 1: Message 4 = "Good morning."
* Message 5 = "Good afternoon."
* Message 7 = "Good evening."
* Message 8 = "Good night."
* Set 4: Message 14 = "Please "
* Message 19 = "Thank you."
* Message 20 = "Sincerely,"
*
* The ICU resource bundle source file would, assuming it is named
* "greet.txt", would look like this:
*
* greet
* {
* 1%4 { "Good morning." }
* 1%5 { "Good afternoon." }
* 1%7 { "Good evening." }
* 1%8 { "Good night." }
*
* 4%14 { "Please " }
* 4%19 { "Thank you." }
* 4%20 { "Sincerely," }
* }
*
* The catgets function is commonly used in combination with functions
* like printf and strftime. ICU components like message format can
* be used instead, although they use a different format syntax.
* There is an ICU package, icuio, that provides some of
* the POSIX-style formatting API.
*/
U_CDECL_BEGIN
/**
* An ICU message catalog descriptor, analogous to nl_catd.
*
* @stable ICU 2.6
*/
typedef UResourceBundle* u_nl_catd;
/**
* Open and return an ICU message catalog descriptor. The descriptor
* may be passed to u_catgets() to retrieve localized strings.
*
* @param name string containing the full path pointing to the
* directory where the resources reside followed by the package name
* e.g. "/usr/resource/my_app/resources/guimessages" on a Unix system.
* If NULL, ICU default data files will be used.
*
* Unlike POSIX, environment variables are not interpolated within the
* name.
*
* @param locale the locale for which we want to open the resource. If
* NULL, the default ICU locale will be used (see uloc_getDefault). If
* strlen(locale) == 0, the root locale will be used.
*
* @param ec input/output error code. Upon output,
* U_USING_FALLBACK_WARNING indicates that a fallback locale was
* used. For example, 'de_CH' was requested, but nothing was found
* there, so 'de' was used. U_USING_DEFAULT_WARNING indicates that the
* default locale data or root locale data was used; neither the
* requested locale nor any of its fallback locales were found.
*
* @return a message catalog descriptor that may be passed to
* u_catgets(). If the ec parameter indicates success, then the caller
* is responsible for calling u_catclose() to close the message
* catalog. If the ec parameter indicates failure, then NULL will be
* returned.
*
* @stable ICU 2.6
*/
U_STABLE u_nl_catd U_EXPORT2
u_catopen(const char* name, const char* locale, UErrorCode* ec);
/**
* Close an ICU message catalog, given its descriptor.
*
* @param catd a message catalog descriptor to be closed. May be NULL,
* in which case no action is taken.
*
* @stable ICU 2.6
*/
U_STABLE void U_EXPORT2
u_catclose(u_nl_catd catd);
/**
* Retrieve a localized string from an ICU message catalog.
*
* @param catd a message catalog descriptor returned by u_catopen.
*
* @param set_num the message catalog set number. Sets need not be
* numbered consecutively.
*
* @param msg_num the message catalog message number within the
* set. Messages need not be numbered consecutively.
*
* @param s the default string. This is returned if the string
* specified by the set_num and msg_num is not found. It must be
* zero-terminated.
*
* @param len fill-in parameter to receive the length of the result.
* May be NULL, in which case it is ignored.
*
* @param ec input/output error code. May be U_USING_FALLBACK_WARNING
* or U_USING_DEFAULT_WARNING. U_MISSING_RESOURCE_ERROR indicates that
* the set_num/msg_num tuple does not specify a valid message string
* in this catalog.
*
* @return a pointer to a zero-terminated UChar array which lives in
* an internal buffer area, typically a memory mapped/DLL file. The
* caller must NOT delete this pointer. If the call is unsuccessful
* for any reason, then s is returned. This includes the situation in
* which ec indicates a failing error code upon entry to this
* function.
*
* @stable ICU 2.6
*/
U_STABLE const UChar* U_EXPORT2
u_catgets(u_nl_catd catd, int32_t set_num, int32_t msg_num,
const UChar* s,
int32_t* len, UErrorCode* ec);
U_CDECL_END
#endif /*UCAT_H*/
/*eof*/