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/*
*******************************************************************************
*
* © 2016 and later: Unicode, Inc. and others.
* License & terms of use: http://www.unicode.org/copyright.html
*
*******************************************************************************
*******************************************************************************
*
* Copyright (C) 2000-2014, International Business Machines
* Corporation and others. All Rights Reserved.
*
*******************************************************************************
* file name: ustring.c
* encoding: UTF-8
* tab size: 8 (not used)
* indentation:4
*
* created on: 2000aug15
* created by: Markus W. Scherer
*
* This file contains sample code that illustrates the use of Unicode strings
* with ICU.
*/
#define __STDC_FORMAT_MACROS 1
#include <inttypes.h>
#include <stdio.h>
#include "unicode/utypes.h"
#include "unicode/uchar.h"
#include "unicode/locid.h"
#include "unicode/ustring.h"
#include "unicode/ucnv.h"
#include "unicode/unistr.h"
using namespace icu;
#ifndef UPRV_LENGTHOF
#define UPRV_LENGTHOF(array) (int32_t)(sizeof(array)/sizeof((array)[0]))
#endif
// helper functions -------------------------------------------------------- ***
// default converter for the platform encoding
static UConverter *cnv=NULL;
static void
printUString(const char *announce, const UChar *s, int32_t length) {
static char out[200];
UChar32 c;
int32_t i;
UErrorCode errorCode=U_ZERO_ERROR;
/*
* Convert to the "platform encoding". See notes in printUnicodeString().
* ucnv_fromUChars(), like most ICU APIs understands length==-1
* to mean that the string is NUL-terminated.
*/
ucnv_fromUChars(cnv, out, sizeof(out), s, length, &errorCode);
if(U_FAILURE(errorCode) || errorCode==U_STRING_NOT_TERMINATED_WARNING) {
printf("%sproblem converting string from Unicode: %s\n", announce, u_errorName(errorCode));
return;
}
printf("%s%s {", announce, out);
/* output the code points (not code units) */
if(length>=0) {
/* s is not NUL-terminated */
for(i=0; i<length; /* U16_NEXT post-increments */) {
U16_NEXT(s, i, length, c);
printf(" %04x", c);
}
} else {
/* s is NUL-terminated */
for(i=0; /* condition in loop body */; /* U16_NEXT post-increments */) {
U16_NEXT(s, i, length, c);
if(c==0) {
break;
}
printf(" %04x", c);
}
}
printf(" }\n");
}
static void
printUnicodeString(const char *announce, const UnicodeString &s) {
static char out[200];
int32_t i, length;
// output the string, converted to the platform encoding
// Note for Windows: The "platform encoding" defaults to the "ANSI codepage",
// which is different from the "OEM codepage" in the console window.
// However, if you pipe the output into a file and look at it with Notepad
// or similar, then "ANSI" characters will show correctly.
// Production code should be aware of what encoding is required,
// and use a UConverter or at least a charset name explicitly.
out[s.extract(0, 99, out)]=0;
printf("%s%s {", announce, out);
// output the code units (not code points)
length=s.length();
for(i=0; i<length; ++i) {
printf(" %04x", s.charAt(i));
}
printf(" }\n");
}
// sample code for utf.h macros -------------------------------------------- ***
static void
demo_utf_h_macros() {
static UChar input[]={ 0x0061, 0xd800, 0xdc00, 0xdbff, 0xdfff, 0x0062 };
UChar32 c;
int32_t i;
UBool isError;
printf("\n* demo_utf_h_macros() -------------- ***\n\n");
printUString("iterate forward through: ", input, UPRV_LENGTHOF(input));
for(i=0; i<UPRV_LENGTHOF(input); /* U16_NEXT post-increments */) {
/* Iterating forwards
Codepoint at offset 0: U+0061
Codepoint at offset 1: U+10000
Codepoint at offset 3: U+10ffff
Codepoint at offset 5: U+0062
*/
printf("Codepoint at offset %d: U+", i);
U16_NEXT(input, i, UPRV_LENGTHOF(input), c);
printf("%04x\n", c);
}
puts("");
isError=false;
i=1; /* write position, gets post-incremented so needs to be in an l-value */
U16_APPEND(input, i, UPRV_LENGTHOF(input), 0x0062, isError);
printUString("iterate backward through: ", input, UPRV_LENGTHOF(input));
for(i=UPRV_LENGTHOF(input); i>0; /* U16_PREV pre-decrements */) {
U16_PREV(input, 0, i, c);
/* Iterating backwards
Codepoint at offset 5: U+0062
Codepoint at offset 3: U+10ffff
Codepoint at offset 2: U+dc00 -- unpaired surrogate because lead surr. overwritten
Codepoint at offset 1: U+0062 -- by this BMP code point
Codepoint at offset 0: U+0061
*/
printf("Codepoint at offset %d: U+%04x\n", i, c);
}
}
// sample code for Unicode strings in C ------------------------------------ ***
static void demo_C_Unicode_strings() {
printf("\n* demo_C_Unicode_strings() --------- ***\n\n");
static const UChar text[]={ 0x41, 0x42, 0x43, 0 }; /* "ABC" */
static const UChar appendText[]={ 0x61, 0x62, 0x63, 0 }; /* "abc" */
static const UChar cmpText[]={ 0x61, 0x53, 0x73, 0x43, 0 }; /* "aSsC" */
UChar buffer[32];
int32_t compare;
int32_t length=u_strlen(text); /* length=3 */
/* simple ANSI C-style functions */
buffer[0]=0; /* empty, NUL-terminated string */
u_strncat(buffer, text, 1); /* append just n=1 character ('A') */
u_strcat(buffer, appendText); /* buffer=="Aabc" */
length=u_strlen(buffer); /* length=4 */
printUString("should be \"Aabc\": ", buffer, -1);
/* bitwise comparing buffer with text */
compare=u_strcmp(buffer, text);
if(compare<=0) {
printf("String comparison error, expected \"Aabc\" > \"ABC\"\n");
}
/* Build "A<sharp s>C" in the buffer... */
u_strcpy(buffer, text);
buffer[1]=0xdf; /* sharp s, case-compares equal to "ss" */
printUString("should be \"A<sharp s>C\": ", buffer, -1);
/* Compare two strings case-insensitively using full case folding */
compare=u_strcasecmp(buffer, cmpText, U_FOLD_CASE_DEFAULT);
if(compare!=0) {
printf("String case insensitive comparison error, expected \"AbC\" to be equal to \"ABC\"\n");
}
}
// sample code for case mappings with C APIs -------------------------------- ***
static void demoCaseMapInC() {
/*
* input=
* "aB<capital sigma>"
* "iI<small dotless i><capital dotted I> "
* "<sharp s> <small lig. ffi>"
* "<small final sigma><small sigma><capital sigma>"
*/
static const UChar input[]={
0x61, 0x42, 0x3a3,
0x69, 0x49, 0x131, 0x130, 0x20,
0xdf, 0x20, 0xfb03,
0x3c2, 0x3c3, 0x3a3, 0
};
UChar buffer[32];
UErrorCode errorCode;
UChar32 c;
int32_t i, j, length;
UBool isError;
printf("\n* demoCaseMapInC() ----------------- ***\n\n");
/*
* First, use simple case mapping functions which provide
* 1:1 code point mappings without context/locale ID.
*
* Note that some mappings will not be "right" because some "real"
* case mappings require context, depend on the locale ID,
* and/or result in a change in the number of code points.
*/
printUString("input string: ", input, -1);
/* uppercase */
isError=false;
for(i=j=0; j<UPRV_LENGTHOF(buffer) && !isError; /* U16_NEXT post-increments */) {
U16_NEXT(input, i, INT32_MAX, c); /* without length because NUL-terminated */
if(c==0) {
break; /* stop at terminating NUL, no need to terminate buffer */
}
c=u_toupper(c);
U16_APPEND(buffer, j, UPRV_LENGTHOF(buffer), c, isError);
}
printUString("simple-uppercased: ", buffer, j);
/* lowercase */
isError=false;
for(i=j=0; j<UPRV_LENGTHOF(buffer) && !isError; /* U16_NEXT post-increments */) {
U16_NEXT(input, i, INT32_MAX, c); /* without length because NUL-terminated */
if(c==0) {
break; /* stop at terminating NUL, no need to terminate buffer */
}
c=u_tolower(c);
U16_APPEND(buffer, j, UPRV_LENGTHOF(buffer), c, isError);
}
printUString("simple-lowercased: ", buffer, j);
/* titlecase */
isError=false;
for(i=j=0; j<UPRV_LENGTHOF(buffer) && !isError; /* U16_NEXT post-increments */) {
U16_NEXT(input, i, INT32_MAX, c); /* without length because NUL-terminated */
if(c==0) {
break; /* stop at terminating NUL, no need to terminate buffer */
}
c=u_totitle(c);
U16_APPEND(buffer, j, UPRV_LENGTHOF(buffer), c, isError);
}
printUString("simple-titlecased: ", buffer, j);
/* case-fold/default */
isError=false;
for(i=j=0; j<UPRV_LENGTHOF(buffer) && !isError; /* U16_NEXT post-increments */) {
U16_NEXT(input, i, INT32_MAX, c); /* without length because NUL-terminated */
if(c==0) {
break; /* stop at terminating NUL, no need to terminate buffer */
}
c=u_foldCase(c, U_FOLD_CASE_DEFAULT);
U16_APPEND(buffer, j, UPRV_LENGTHOF(buffer), c, isError);
}
printUString("simple-case-folded/default: ", buffer, j);
/* case-fold/Turkic */
isError=false;
for(i=j=0; j<UPRV_LENGTHOF(buffer) && !isError; /* U16_NEXT post-increments */) {
U16_NEXT(input, i, INT32_MAX, c); /* without length because NUL-terminated */
if(c==0) {
break; /* stop at terminating NUL, no need to terminate buffer */
}
c=u_foldCase(c, U_FOLD_CASE_EXCLUDE_SPECIAL_I);
U16_APPEND(buffer, j, UPRV_LENGTHOF(buffer), c, isError);
}
printUString("simple-case-folded/Turkic: ", buffer, j);
/*
* Second, use full case mapping functions which provide
* 1:n code point mappings (n can be 0!) and are sensitive to context and locale ID.
*
* Note that lower/upper/titlecasing take a locale ID while case-folding
* has bit flag options instead, by design of the Unicode SpecialCasing.txt UCD file.
*
* Also, string titlecasing requires a BreakIterator to find starts of words.
* The sample code here passes in a NULL pointer; u_strToTitle() will open and close a default
* titlecasing BreakIterator automatically.
* For production code where many strings are titlecased it would be more efficient
* to open a BreakIterator externally and pass it in.
*/
printUString("\ninput string: ", input, -1);
/* lowercase/English */
errorCode=U_ZERO_ERROR;
length=u_strToLower(buffer, UPRV_LENGTHOF(buffer), input, -1, "en", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-lowercased/en: ", buffer, length);
} else {
printf("error in u_strToLower(en)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* lowercase/Turkish */
errorCode=U_ZERO_ERROR;
length=u_strToLower(buffer, UPRV_LENGTHOF(buffer), input, -1, "tr", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-lowercased/tr: ", buffer, length);
} else {
printf("error in u_strToLower(tr)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* uppercase/English */
errorCode=U_ZERO_ERROR;
length=u_strToUpper(buffer, UPRV_LENGTHOF(buffer), input, -1, "en", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-uppercased/en: ", buffer, length);
} else {
printf("error in u_strToUpper(en)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* uppercase/Turkish */
errorCode=U_ZERO_ERROR;
length=u_strToUpper(buffer, UPRV_LENGTHOF(buffer), input, -1, "tr", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-uppercased/tr: ", buffer, length);
} else {
printf("error in u_strToUpper(tr)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* titlecase/English */
errorCode=U_ZERO_ERROR;
length=u_strToTitle(buffer, UPRV_LENGTHOF(buffer), input, -1, NULL, "en", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-titlecased/en: ", buffer, length);
} else {
printf("error in u_strToTitle(en)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* titlecase/Turkish */
errorCode=U_ZERO_ERROR;
length=u_strToTitle(buffer, UPRV_LENGTHOF(buffer), input, -1, NULL, "tr", &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-titlecased/tr: ", buffer, length);
} else {
printf("error in u_strToTitle(tr)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* case-fold/default */
errorCode=U_ZERO_ERROR;
length=u_strFoldCase(buffer, UPRV_LENGTHOF(buffer), input, -1, U_FOLD_CASE_DEFAULT, &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-case-folded/default: ", buffer, length);
} else {
printf("error in u_strFoldCase(default)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
/* case-fold/Turkic */
errorCode=U_ZERO_ERROR;
length=u_strFoldCase(buffer, UPRV_LENGTHOF(buffer), input, -1, U_FOLD_CASE_EXCLUDE_SPECIAL_I, &errorCode);
if(U_SUCCESS(errorCode)) {
printUString("full-case-folded/Turkic: ", buffer, length);
} else {
printf("error in u_strFoldCase(Turkic)=%" PRId32 " error=%s\n", length, u_errorName(errorCode));
}
}
// sample code for case mappings with C++ APIs ------------------------------ ***
static void demoCaseMapInCPlusPlus() {
/*
* input=
* "aB<capital sigma>"
* "iI<small dotless i><capital dotted I> "
* "<sharp s> <small lig. ffi>"
* "<small final sigma><small sigma><capital sigma>"
*/
static const UChar input[]={
0x61, 0x42, 0x3a3,
0x69, 0x49, 0x131, 0x130, 0x20,
0xdf, 0x20, 0xfb03,
0x3c2, 0x3c3, 0x3a3, 0
};
printf("\n* demoCaseMapInCPlusPlus() --------- ***\n\n");
UnicodeString s(input), t;
const Locale &en=Locale::getEnglish();
Locale tr("tr");
/*
* Full case mappings as in demoCaseMapInC(), using UnicodeString functions.
* These functions modify the string object itself.
* Since we want to keep the input string around, we copy it each time
* and case-map the copy.
*/
printUnicodeString("input string: ", s);
/* lowercase/English */
printUnicodeString("full-lowercased/en: ", (t=s).toLower(en));
/* lowercase/Turkish */
printUnicodeString("full-lowercased/tr: ", (t=s).toLower(tr));
/* uppercase/English */
printUnicodeString("full-uppercased/en: ", (t=s).toUpper(en));
/* uppercase/Turkish */
printUnicodeString("full-uppercased/tr: ", (t=s).toUpper(tr));
/* titlecase/English */
printUnicodeString("full-titlecased/en: ", (t=s).toTitle(NULL, en));
/* titlecase/Turkish */
printUnicodeString("full-titlecased/tr: ", (t=s).toTitle(NULL, tr));
/* case-folde/default */
printUnicodeString("full-case-folded/default: ", (t=s).foldCase(U_FOLD_CASE_DEFAULT));
/* case-folde/Turkic */
printUnicodeString("full-case-folded/Turkic: ", (t=s).foldCase(U_FOLD_CASE_EXCLUDE_SPECIAL_I));
}
// sample code for UnicodeString storage models ----------------------------- ***
static const UChar readonly[]={
0x61, 0x31, 0x20ac
};
static UChar writeable[]={
0x62, 0x32, 0xdbc0, 0xdc01 // includes a surrogate pair for a supplementary code point
};
static char out[100];
static void
demoUnicodeStringStorage() {
// These sample code lines illustrate how to use UnicodeString, and the
// comments tell what happens internally. There are no APIs to observe
// most of this programmatically, except for stepping into the code
// with a debugger.
// This is by design to hide such details from the user.
int32_t i;
printf("\n* demoUnicodeStringStorage() ------- ***\n\n");
// * UnicodeString with internally stored contents
// instantiate a UnicodeString from a single code point
// the few (2) UChars will be stored in the object itself
UnicodeString one((UChar32)0x24001);
// this copies the few UChars into the "two" object
UnicodeString two=one;
printf("length of short string copy: %d\n", two.length());
// set "one" to contain the 3 UChars from readonly
// this setTo() variant copies the characters
one.setTo(readonly, UPRV_LENGTHOF(readonly));
// * UnicodeString with allocated contents
// build a longer string that will not fit into the object's buffer
one+=UnicodeString(writeable, UPRV_LENGTHOF(writeable));
one+=one;
one+=one;
printf("length of longer string: %d\n", one.length());
// copying will use the same allocated buffer and increment the reference
// counter
two=one;
printf("length of longer string copy: %d\n", two.length());
// * UnicodeString using readonly-alias to a const UChar array
// construct a string that aliases a readonly buffer
UnicodeString three(false, readonly, UPRV_LENGTHOF(readonly));
printUnicodeString("readonly-alias string: ", three);
// copy-on-write: any modification to the string results in
// a copy to either the internal buffer or to a newly allocated one
three.setCharAt(1, 0x39);
printUnicodeString("readonly-aliasing string after modification: ", three);
// the aliased array is not modified
for(i=0; i<three.length(); ++i) {
printf("readonly buffer[%d] after modifying its string: 0x%" PRId32 "\n",
i, readonly[i]);
}
// setTo() readonly alias
one.setTo(false, writeable, UPRV_LENGTHOF(writeable));
// copying the readonly-alias object with fastCopyFrom() (new in ICU 2.4)
// will readonly-alias the same buffer
two.fastCopyFrom(one);
printUnicodeString("fastCopyFrom(readonly alias of \"writeable\" array): ", two);
printf("verify that a fastCopyFrom(readonly alias) uses the same buffer pointer: %d (should be 1)\n",
one.getBuffer()==two.getBuffer());
// a normal assignment will clone the contents (new in ICU 2.4)
two=one;
printf("verify that a regular copy of a readonly alias uses a different buffer pointer: %d (should be 0)\n",
one.getBuffer()==two.getBuffer());
// * UnicodeString using writeable-alias to a non-const UChar array
UnicodeString four(writeable, UPRV_LENGTHOF(writeable), UPRV_LENGTHOF(writeable));
printUnicodeString("writeable-alias string: ", four);
// a modification writes through to the buffer
four.setCharAt(1, 0x39);
for(i=0; i<four.length(); ++i) {
printf("writeable-alias backing buffer[%d]=0x%" PRId32 " "
"after modification\n", i, writeable[i]);
}
// a copy will not alias any more;
// instead, it will get a copy of the contents into allocated memory
two=four;
two.setCharAt(1, 0x21);
for(i=0; i<two.length(); ++i) {
printf("writeable-alias backing buffer[%d]=0x%" PRId32 " after "
"modification of string copy\n", i, writeable[i]);
}
// setTo() writeable alias, capacity==length
one.setTo(writeable, UPRV_LENGTHOF(writeable), UPRV_LENGTHOF(writeable));
// grow the string - it will not fit into the backing buffer any more
// and will get copied before modification
one.append((UChar)0x40);
// shrink it back so it would fit
one.truncate(one.length()-1);
// we still operate on the copy
one.setCharAt(1, 0x25);
printf("string after growing too much and then shrinking[1]=0x%" PRId32 "\n"
" backing store for this[1]=0x%" PRId32 "\n",
one.charAt(1), writeable[1]);
// if we need it in the original buffer, then extract() to it
// extract() does not do anything if the string aliases that same buffer
// i=min(one.length(), length of array)
if(one.length()<UPRV_LENGTHOF(writeable)) {
i=one.length();
} else {
i=UPRV_LENGTHOF(writeable);
}
one.extract(0, i, writeable);
for(i=0; i<UPRV_LENGTHOF(writeable); ++i) {
printf("writeable-alias backing buffer[%d]=0x%" PRId32 " after re-extract\n",
i, writeable[i]);
}
}
// sample code for UnicodeString instantiations ----------------------------- ***
static void
demoUnicodeStringInit() {
// *** Make sure to read about invariant characters in utypes.h! ***
// Initialization of Unicode strings from C literals works _only_ for
// invariant characters!
printf("\n* demoUnicodeStringInit() ---------- ***\n\n");
// the string literal is 32 chars long - this must be counted for the macro
UnicodeString invariantOnly=UNICODE_STRING("such characters are safe 123 %-.", 32);
/*
* In C, we need two macros: one to declare the UChar[] array, and
* one to populate it; the second one is a noop on platforms where
* wchar_t is compatible with UChar and ASCII-based.
* The length of the string literal must be counted for both macros.
*/
/* declare the invString array for the string */
U_STRING_DECL(invString, "such characters are safe 123 %-.", 32);
/* populate it with the characters */
U_STRING_INIT(invString, "such characters are safe 123 %-.", 32);
// compare the C and C++ strings
printf("C and C++ Unicode strings are equal: %d\n", invariantOnly==UnicodeString(true, invString, 32));
/*
* convert between char * and UChar * strings that
* contain only invariant characters
*/
static const char *cs1="such characters are safe 123 %-.";
static UChar us1[40];
static char cs2[40];
u_charsToUChars(cs1, us1, 33); /* include the terminating NUL */
u_UCharsToChars(us1, cs2, 33);
printf("char * -> UChar * -> char * with only "
"invariant characters: \"%s\"\n",
cs2);
// initialize a UnicodeString from a string literal that contains
// escape sequences written with invariant characters
// do not forget to duplicate the backslashes for ICU to see them
// then, count each double backslash only once!
UnicodeString german=UNICODE_STRING(
"Sch\\u00f6nes Auto: \\u20ac 11240.\\fPrivates Zeichen: \\U00102345\\n", 64).
unescape();
printUnicodeString("german UnicodeString from unescaping:\n ", german);
/*
* C: convert and unescape a char * string with only invariant
* characters to fill a UChar * string
*/
UChar buffer[200];
int32_t length;
length=u_unescape(
"Sch\\u00f6nes Auto: \\u20ac 11240.\\fPrivates Zeichen: \\U00102345\\n",
buffer, UPRV_LENGTHOF(buffer));
printf("german C Unicode string from char * unescaping: (length %d)\n ", length);
printUnicodeString("", UnicodeString(buffer));
}
extern int
main(int argc, const char *argv[]) {
UErrorCode errorCode=U_ZERO_ERROR;
// Note: Using a global variable for any object is not exactly thread-safe...
// You can change this call to e.g. ucnv_open("UTF-8", &errorCode) if you pipe
// the output to a file and look at it with a Unicode-capable editor.
// This will currently affect only the printUString() function, see the code above.
// printUnicodeString() could use this, too, by changing to an extract() overload
// that takes a UConverter argument.
cnv=ucnv_open(NULL, &errorCode);
if(U_FAILURE(errorCode)) {
fprintf(stderr, "error %s opening the default converter\n", u_errorName(errorCode));
return errorCode;
}
ucnv_setFromUCallBack(cnv, UCNV_FROM_U_CALLBACK_ESCAPE, UCNV_ESCAPE_C, NULL, NULL, &errorCode);
if(U_FAILURE(errorCode)) {
fprintf(stderr, "error %s setting the escape callback in the default converter\n", u_errorName(errorCode));
ucnv_close(cnv);
return errorCode;
}
demo_utf_h_macros();
demo_C_Unicode_strings();
demoCaseMapInC();
demoCaseMapInCPlusPlus();
demoUnicodeStringStorage();
demoUnicodeStringInit();
ucnv_close(cnv);
return 0;
}
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