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-rw-r--r--Build/source/libs/icu/icu-4.8.1/i18n/bocsu.cpp153
1 files changed, 153 insertions, 0 deletions
diff --git a/Build/source/libs/icu/icu-4.8.1/i18n/bocsu.cpp b/Build/source/libs/icu/icu-4.8.1/i18n/bocsu.cpp
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index 00000000000..6e473dcfc87
--- /dev/null
+++ b/Build/source/libs/icu/icu-4.8.1/i18n/bocsu.cpp
@@ -0,0 +1,153 @@
+/*
+*******************************************************************************
+* Copyright (C) 2001-2011, International Business Machines
+* Corporation and others. All Rights Reserved.
+*******************************************************************************
+* file name: bocsu.cpp
+* encoding: US-ASCII
+* tab size: 8 (not used)
+* indentation:4
+*
+* Author: Markus W. Scherer
+*
+* Modification history:
+* 05/18/2001 weiv Made into separate module
+*/
+
+
+#include "unicode/utypes.h"
+#include "unicode/bytestream.h"
+
+#if !UCONFIG_NO_COLLATION
+
+#include "bocsu.h"
+
+/*
+ * encode one difference value -0x10ffff..+0x10ffff in 1..3 bytes,
+ * preserving lexical order
+ */
+U_CFUNC uint8_t *
+u_writeDiff(int32_t diff, uint8_t *p) {
+ if(diff>=SLOPE_REACH_NEG_1) {
+ if(diff<=SLOPE_REACH_POS_1) {
+ *p++=(uint8_t)(SLOPE_MIDDLE+diff);
+ } else if(diff<=SLOPE_REACH_POS_2) {
+ *p++=(uint8_t)(SLOPE_START_POS_2+(diff/SLOPE_TAIL_COUNT));
+ *p++=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ } else if(diff<=SLOPE_REACH_POS_3) {
+ p[2]=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ diff/=SLOPE_TAIL_COUNT;
+ p[1]=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ *p=(uint8_t)(SLOPE_START_POS_3+(diff/SLOPE_TAIL_COUNT));
+ p+=3;
+ } else {
+ p[3]=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ diff/=SLOPE_TAIL_COUNT;
+ p[2]=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ diff/=SLOPE_TAIL_COUNT;
+ p[1]=(uint8_t)(SLOPE_MIN+diff%SLOPE_TAIL_COUNT);
+ *p=SLOPE_MAX;
+ p+=4;
+ }
+ } else {
+ int32_t m;
+
+ if(diff>=SLOPE_REACH_NEG_2) {
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ *p++=(uint8_t)(SLOPE_START_NEG_2+diff);
+ *p++=(uint8_t)(SLOPE_MIN+m);
+ } else if(diff>=SLOPE_REACH_NEG_3) {
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ p[2]=(uint8_t)(SLOPE_MIN+m);
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ p[1]=(uint8_t)(SLOPE_MIN+m);
+ *p=(uint8_t)(SLOPE_START_NEG_3+diff);
+ p+=3;
+ } else {
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ p[3]=(uint8_t)(SLOPE_MIN+m);
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ p[2]=(uint8_t)(SLOPE_MIN+m);
+ NEGDIVMOD(diff, SLOPE_TAIL_COUNT, m);
+ p[1]=(uint8_t)(SLOPE_MIN+m);
+ *p=SLOPE_MIN;
+ p+=4;
+ }
+ }
+ return p;
+}
+
+/*
+ * Encode the code points of a string as
+ * a sequence of byte-encoded differences (slope detection),
+ * preserving lexical order.
+ *
+ * Optimize the difference-taking for runs of Unicode text within
+ * small scripts:
+ *
+ * Most small scripts are allocated within aligned 128-blocks of Unicode
+ * code points. Lexical order is preserved if "prev" is always moved
+ * into the middle of such a block.
+ *
+ * Additionally, "prev" is moved from anywhere in the Unihan
+ * area into the middle of that area.
+ * Note that the identical-level run in a sort key is generated from
+ * NFD text - there are never Hangul characters included.
+ */
+U_CFUNC void
+u_writeIdenticalLevelRun(const UChar *s, int32_t length, U_NAMESPACE_QUALIFIER ByteSink &sink) {
+ char scratch[64];
+ int32_t capacity;
+
+ UChar32 prev=0;
+ int32_t i=0;
+ while(i<length) {
+ char *buffer=sink.GetAppendBuffer(1, length*2, scratch, (int32_t)sizeof(scratch), &capacity);
+ uint8_t *p;
+ // We must have capacity>=SLOPE_MAX_BYTES in case u_writeDiff() writes that much,
+ // but we do not want to force the sink.GetAppendBuffer() to allocate
+ // for a large min_capacity because we might actually only write one byte.
+ if(capacity<16) {
+ buffer=scratch;
+ capacity=(int32_t)sizeof(scratch);
+ }
+ p=reinterpret_cast<uint8_t *>(buffer);
+ uint8_t *lastSafe=p+capacity-SLOPE_MAX_BYTES;
+ while(i<length && p<=lastSafe) {
+ if(prev<0x4e00 || prev>=0xa000) {
+ prev=(prev&~0x7f)-SLOPE_REACH_NEG_1;
+ } else {
+ /*
+ * Unihan U+4e00..U+9fa5:
+ * double-bytes down from the upper end
+ */
+ prev=0x9fff-SLOPE_REACH_POS_2;
+ }
+
+ UChar32 c;
+ U16_NEXT(s, i, length, c);
+ p=u_writeDiff(c-prev, p);
+ prev=c;
+ }
+ sink.Append(buffer, (int32_t)(p-reinterpret_cast<uint8_t *>(buffer)));
+ }
+}
+
+U_CFUNC int32_t
+u_writeIdenticalLevelRunTwoChars(UChar32 first, UChar32 second, uint8_t *p) {
+ uint8_t *p0 = p;
+ if(first<0x4e00 || first>=0xa000) {
+ first=(first&~0x7f)-SLOPE_REACH_NEG_1;
+ } else {
+ /*
+ * Unihan U+4e00..U+9fa5:
+ * double-bytes down from the upper end
+ */
+ first=0x9fff-SLOPE_REACH_POS_2;
+ }
+
+ p=u_writeDiff(second-first, p);
+ return (int32_t)(p-p0);
+}
+
+#endif /* #if !UCONFIG_NO_COLLATION */