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-rw-r--r--src/core/basetypes/icu-ucsdet/inputext.cpp164
1 files changed, 164 insertions, 0 deletions
diff --git a/src/core/basetypes/icu-ucsdet/inputext.cpp b/src/core/basetypes/icu-ucsdet/inputext.cpp
new file mode 100644
index 00000000..e5a8ee18
--- /dev/null
+++ b/src/core/basetypes/icu-ucsdet/inputext.cpp
@@ -0,0 +1,164 @@
+/*
+ **********************************************************************
+ * Copyright (C) 2005-2009, International Business Machines
+ * Corporation and others. All Rights Reserved.
+ **********************************************************************
+ */
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_CONVERSION
+
+#include "inputext.h"
+
+#include "cmemory.h"
+#include "cstring.h"
+
+#include <string.h>
+
+U_NAMESPACE_BEGIN
+
+#define BUFFER_SIZE 8192
+
+#define ARRAY_SIZE(array) (sizeof array / sizeof array[0])
+
+#define NEW_ARRAY(type,count) (type *) uprv_malloc((count) * sizeof(type))
+#define DELETE_ARRAY(array) uprv_free((void *) (array))
+
+InputText::InputText(UErrorCode &status)
+ : fInputBytes(NEW_ARRAY(uint8_t, BUFFER_SIZE)), // The text to be checked. Markup will have been
+ // removed if appropriate.
+ fByteStats(NEW_ARRAY(int16_t, 256)), // byte frequency statistics for the input text.
+ // Value is percent, not absolute.
+ fDeclaredEncoding(0),
+ fRawInput(0),
+ fRawLength(0)
+{
+ if (fInputBytes == NULL || fByteStats == NULL) {
+ status = U_MEMORY_ALLOCATION_ERROR;
+ }
+}
+
+InputText::~InputText()
+{
+ DELETE_ARRAY(fDeclaredEncoding);
+ DELETE_ARRAY(fByteStats);
+ DELETE_ARRAY(fInputBytes);
+}
+
+void InputText::setText(const char *in, int32_t len)
+{
+ fInputLen = 0;
+ fC1Bytes = FALSE;
+ fRawInput = (const uint8_t *) in;
+ fRawLength = len == -1? (int32_t)uprv_strlen(in) : len;
+}
+
+void InputText::setDeclaredEncoding(const char* encoding, int32_t len)
+{
+ if(encoding) {
+ if (len == -1) {
+ len = (int32_t)uprv_strlen(encoding);
+ }
+
+ len += 1; // to make place for the \0 at the end.
+ uprv_free(fDeclaredEncoding);
+ fDeclaredEncoding = NEW_ARRAY(char, len);
+ uprv_strncpy(fDeclaredEncoding, encoding, len);
+ }
+}
+
+UBool InputText::isSet() const
+{
+ return fRawInput != NULL;
+}
+
+/**
+* MungeInput - after getting a set of raw input data to be analyzed, preprocess
+* it by removing what appears to be html markup.
+*
+* @internal
+*/
+void InputText::MungeInput(UBool fStripTags) {
+ int srci = 0;
+ int dsti = 0;
+ uint8_t b;
+ bool inMarkup = FALSE;
+ int32_t openTags = 0;
+ int32_t badTags = 0;
+
+ //
+ // html / xml markup stripping.
+ // quick and dirty, not 100% accurate, but hopefully good enough, statistically.
+ // discard everything within < brackets >
+ // Count how many total '<' and illegal (nested) '<' occur, so we can make some
+ // guess as to whether the input was actually marked up at all.
+ // TODO: Think about how this interacts with EBCDIC charsets that are detected.
+ if (fStripTags) {
+ for (srci = 0; srci < fRawLength && dsti < BUFFER_SIZE; srci += 1) {
+ b = fRawInput[srci];
+
+ if (b == (uint8_t)0x3C) { /* Check for the ASCII '<' */
+ if (inMarkup) {
+ badTags += 1;
+ }
+
+ inMarkup = TRUE;
+ openTags += 1;
+ }
+
+ if (! inMarkup) {
+ fInputBytes[dsti++] = b;
+ }
+
+ if (b == (uint8_t)0x3E) { /* Check for the ASCII '>' */
+ inMarkup = FALSE;
+ }
+ }
+
+ fInputLen = dsti;
+ }
+
+ //
+ // If it looks like this input wasn't marked up, or if it looks like it's
+ // essentially nothing but markup abandon the markup stripping.
+ // Detection will have to work on the unstripped input.
+ //
+ if (openTags<5 || openTags/5 < badTags ||
+ (fInputLen < 100 && fRawLength>600))
+ {
+ int32_t limit = fRawLength;
+
+ if (limit > BUFFER_SIZE) {
+ limit = BUFFER_SIZE;
+ }
+
+ for (srci=0; srci<limit; srci++) {
+ fInputBytes[srci] = fRawInput[srci];
+ }
+
+ fInputLen = srci;
+ }
+
+ //
+ // Tally up the byte occurence statistics.
+ // These are available for use by the various detectors.
+ //
+
+ uprv_memset(fByteStats, 0, (sizeof fByteStats[0]) * 256);
+
+ for (srci = 0; srci < fInputLen; srci += 1) {
+ fByteStats[fInputBytes[srci]] += 1;
+ }
+
+ for (int32_t i = 0x80; i <= 0x9F; i += 1) {
+ if (fByteStats[i] != 0) {
+ fC1Bytes = TRUE;
+ break;
+ }
+ }
+}
+
+U_NAMESPACE_END
+#endif
+