--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/WebCore/icu/unicode/ucsdet.h Fri Sep 17 09:02:29 2010 +0300
@@ -0,0 +1,350 @@
+/*
+ **********************************************************************
+ * Copyright (C) 2005-2006, International Business Machines
+ * Corporation and others. All Rights Reserved.
+ **********************************************************************
+ * file name: ucsdet.h
+ * encoding: US-ASCII
+ * indentation:4
+ *
+ * created on: 2005Aug04
+ * created by: Andy Heninger
+ *
+ * ICU Character Set Detection, API for C
+ *
+ * Draft version 18 Oct 2005
+ *
+ */
+
+#ifndef __UCSDET_H
+#define __UCSDET_H
+
+#include "unicode/utypes.h"
+
+#if !UCONFIG_NO_CONVERSION
+#include "unicode/uenum.h"
+
+/**
+ * \file
+ * \brief C API: Charset Detection API
+ *
+ * This API provides a facility for detecting the
+ * charset or encoding of character data in an unknown text format.
+ * The input data can be from an array of bytes.
+ * <p>
+ * Character set detection is at best an imprecise operation. The detection
+ * process will attempt to identify the charset that best matches the characteristics
+ * of the byte data, but the process is partly statistical in nature, and
+ * the results can not be guaranteed to always be correct.
+ * <p>
+ * For best accuracy in charset detection, the input data should be primarily
+ * in a single language, and a minimum of a few hundred bytes worth of plain text
+ * in the language are needed. The detection process will attempt to
+ * ignore html or xml style markup that could otherwise obscure the content.
+ */
+
+
+struct UCharsetDetector;
+/**
+ * Structure representing a charset detector
+ * @draft ICU 3.6
+ */
+typedef struct UCharsetDetector UCharsetDetector;
+
+struct UCharsetMatch;
+/**
+ * Opaque structure representing a match that was identified
+ * from a charset detection operation.
+ * @draft ICU 3.6
+ */
+typedef struct UCharsetMatch UCharsetMatch;
+
+/**
+ * Open a charset detector.
+ *
+ * @param status Any error conditions occurring during the open
+ * operation are reported back in this variable.
+ * @return the newly opened charset detector.
+ * @draft ICU 3.6
+ */
+U_DRAFT UCharsetDetector * U_EXPORT2
+ucsdet_open(UErrorCode *status);
+
+/**
+ * Close a charset detector. All storage and any other resources
+ * owned by this charset detector will be released. Failure to
+ * close a charset detector when finished with it can result in
+ * memory leaks in the application.
+ *
+ * @param ucsd The charset detector to be closed.
+ * @draft ICU 3.6
+ */
+U_DRAFT void U_EXPORT2
+ucsdet_close(UCharsetDetector *ucsd);
+
+/**
+ * Set the input byte data whose charset is to detected.
+ *
+ * Ownership of the input text byte array remains with the caller.
+ * The input string must not be altered or deleted until the charset
+ * detector is either closed or reset to refer to different input text.
+ *
+ * @param ucsd the charset detector to be used.
+ * @param textIn the input text of unknown encoding. .
+ * @param len the length of the input text, or -1 if the text
+ * is NUL terminated.
+ * @param status any error conditions are reported back in this variable.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT void U_EXPORT2
+ucsdet_setText(UCharsetDetector *ucsd, const char *textIn, int32_t len, UErrorCode *status);
+
+
+/** Set the declared encoding for charset detection.
+ * The declared encoding of an input text is an encoding obtained
+ * by the user from an http header or xml declaration or similar source that
+ * can be provided as an additional hint to the charset detector.
+ *
+ * How and whether the declared encoding will be used during the
+ * detection process is TBD.
+ *
+ * @param ucsd the charset detector to be used.
+ * @param encoding an encoding for the current data obtained from
+ * a header or declaration or other source outside
+ * of the byte data itself.
+ * @param length the length of the encoding name, or -1 if the name string
+ * is NUL terminated.
+ * @param status any error conditions are reported back in this variable.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT void U_EXPORT2
+ucsdet_setDeclaredEncoding(UCharsetDetector *ucsd, const char *encoding, int32_t length, UErrorCode *status);
+
+
+/**
+ * Return the charset that best matches the supplied input data.
+ *
+ * Note though, that because the detection
+ * only looks at the start of the input data,
+ * there is a possibility that the returned charset will fail to handle
+ * the full set of input data.
+ * <p>
+ * The returned UCharsetMatch object is owned by the UCharsetDetector.
+ * It will remain valid until the detector input is reset, or until
+ * the detector is closed.
+ * <p>
+ * The function will fail if
+ * <ul>
+ * <li>no charset appears to match the data.</li>
+ * <li>no input text has been provided</li>
+ * </ul>
+ *
+ * @param ucsd the charset detector to be used.
+ * @param status any error conditions are reported back in this variable.
+ * @return a UCharsetMatch representing the best matching charset,
+ * or NULL if no charset matches the byte data.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT const UCharsetMatch * U_EXPORT2
+ucsdet_detect(UCharsetDetector *ucsd, UErrorCode *status);
+
+
+/**
+ * Find all charset matches that appear to be consistent with the input,
+ * returning an array of results. The results are ordered with the
+ * best quality match first.
+ *
+ * Because the detection only looks at a limited amount of the
+ * input byte data, some of the returned charsets may fail to handle
+ * the all of input data.
+ * <p>
+ * The returned UCharsetMatch objects are owned by the UCharsetDetector.
+ * They will remain valid until the detector is closed or modified
+ *
+ * <p>
+ * Return an error if
+ * <ul>
+ * <li>no charsets appear to match the input data.</li>
+ * <li>no input text has been provided</li>
+ * </ul>
+ *
+ * @param ucsd the charset detector to be used.
+ * @param matchesFound pointer to a variable that will be set to the
+ * number of charsets identified that are consistent with
+ * the input data. Output only.
+ * @param status any error conditions are reported back in this variable.
+ * @return A pointer to an array of pointers to UCharSetMatch objects.
+ * This array, and the UCharSetMatch instances to which it refers,
+ * are owned by the UCharsetDetector, and will remain valid until
+ * the detector is closed or modified.
+ * @draft ICU 3.4
+ */
+U_DRAFT const UCharsetMatch ** U_EXPORT2
+ucsdet_detectAll(UCharsetDetector *ucsd, int32_t *matchesFound, UErrorCode *status);
+
+
+
+/**
+ * Get the name of the charset represented by a UCharsetMatch.
+ *
+ * The storage for the returned name string is owned by the
+ * UCharsetMatch, and will remain valid while the UCharsetMatch
+ * is valid.
+ *
+ * The name returned is suitable for use with the ICU conversion APIs.
+ *
+ * @param ucsm The charset match object.
+ * @param status Any error conditions are reported back in this variable.
+ * @return The name of the matching charset.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT const char * U_EXPORT2
+ucsdet_getName(const UCharsetMatch *ucsm, UErrorCode *status);
+
+/**
+ * Get a confidence number for the quality of the match of the byte
+ * data with the charset. Confidence numbers range from zero to 100,
+ * with 100 representing complete confidence and zero representing
+ * no confidence.
+ *
+ * The confidence values are somewhat arbitrary. They define an
+ * an ordering within the results for any single detection operation
+ * but are not generally comparable between the results for different input.
+ *
+ * A confidence value of ten does have a general meaning - it is used
+ * for charsets that can represent the input data, but for which there
+ * is no other indication that suggests that the charset is the correct one.
+ * Pure 7 bit ASCII data, for example, is compatible with a
+ * great many charsets, most of which will appear as possible matches
+ * with a confidence of 10.
+ *
+ * @param ucsm The charset match object.
+ * @param status Any error conditions are reported back in this variable.
+ * @return A confidence number for the charset match.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT int32_t U_EXPORT2
+ucsdet_getConfidence(const UCharsetMatch *ucsm, UErrorCode *status);
+
+/**
+ * Get the RFC 3066 code for the language of the input data.
+ *
+ * The Charset Detection service is intended primarily for detecting
+ * charsets, not language. For some, but not all, charsets, a language is
+ * identified as a byproduct of the detection process, and that is what
+ * is returned by this function.
+ *
+ * CAUTION:
+ * 1. Language information is not available for input data encoded in
+ * all charsets. In particular, no language is identified
+ * for UTF-8 input data.
+ *
+ * 2. Closely related languages may sometimes be confused.
+ *
+ * If more accurate language detection is required, a linguistic
+ * analysis package should be used.
+ *
+ * The storage for the returned name string is owned by the
+ * UCharsetMatch, and will remain valid while the UCharsetMatch
+ * is valid.
+ *
+ * @param ucsm The charset match object.
+ * @param status Any error conditions are reported back in this variable.
+ * @return The RFC 3066 code for the language of the input data, or
+ * an empty string if the language could not be determined.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT const char * U_EXPORT2
+ucsdet_getLanguage(const UCharsetMatch *ucsm, UErrorCode *status);
+
+
+/**
+ * Get the entire input text as a UChar string, placing it into
+ * a caller-supplied buffer. A terminating
+ * NUL character will be appended to the buffer if space is available.
+ *
+ * The number of UChars in the output string, not including the terminating
+ * NUL, is returned.
+ *
+ * If the supplied buffer is smaller than required to hold the output,
+ * the contents of the buffer are undefined. The full output string length
+ * (in UChars) is returned as always, and can be used to allocate a buffer
+ * of the correct size.
+ *
+ *
+ * @param ucsm The charset match object.
+ * @param buf A UChar buffer to be filled with the converted text data.
+ * @param cap The capacity of the buffer in UChars.
+ * @param status Any error conditions are reported back in this variable.
+ * @return The number of UChars in the output string.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT int32_t U_EXPORT2
+ucsdet_getUChars(const UCharsetMatch *ucsm,
+ UChar *buf, int32_t cap, UErrorCode *status);
+
+
+
+/**
+ * Get an iterator over the set of all detectable charsets -
+ * over the charsets that are known to the charset detection
+ * service.
+ *
+ * The returned UEnumeration provides access to the names of
+ * the charsets.
+ *
+ * The state of the Charset detector that is passed in does not
+ * affect the result of this function, but requiring a valid, open
+ * charset detector as a parameter insures that the charset detection
+ * service has been safely initialized and that the required detection
+ * data is available.
+ *
+ * @param ucsd a Charset detector.
+ * @param status Any error conditions are reported back in this variable.
+ * @return an iterator providing access to the detectable charset names.
+ * @draft ICU 3.6
+ */
+
+U_DRAFT UEnumeration * U_EXPORT2
+ucsdet_getAllDetectableCharsets(const UCharsetDetector *ucsd, UErrorCode *status);
+
+
+/**
+ * Test whether input filtering is enabled for this charset detector.
+ * Input filtering removes text that appears to be HTML or xml
+ * markup from the input before applying the code page detection
+ * heuristics.
+ *
+ * @param ucsd The charset detector to check.
+ * @return TRUE if filtering is enabled.
+ * @draft ICU 3.4
+ */
+U_DRAFT UBool U_EXPORT2
+ucsdet_isInputFilterEnabled(const UCharsetDetector *ucsd);
+
+
+/**
+ * Enable filtering of input text. If filtering is enabled,
+ * text within angle brackets ("<" and ">") will be removed
+ * before detection, which will remove most HTML or xml markup.
+ *
+ * @param ucsd the charset detector to be modified.
+ * @param filter <code>true</code> to enable input text filtering.
+ * @return The previous setting.
+ *
+ * @draft ICU 3.6
+ */
+U_DRAFT UBool U_EXPORT2
+ucsdet_enableInputFilter(UCharsetDetector *ucsd, UBool filter);
+
+#endif
+#endif /* __UCSDET_H */
+
+