Add acmart template

[lyx.git] / src / support / unicode.h

diff --git a/src/support/unicode.h b/src/support/unicode.h
index 21ff21afb5d61fb5847abcaece15a46a1c96a65f..17b95dd29079c7ad69ac7efa110647dd0cdd17a1 100644 (file)
--- a/src/support/unicode.h
+++ b/src/support/unicode.h
@@ -1,9 +1,10 @@
+// -*- C++ -*-
 /**
  * \file unicode.h
  * This file is part of LyX, the document processor.
  * Licence details can be found in the file COPYING.
  *
- * \author Lars Gullik Bjønnes
+ * \author Lars Gullik Bjønnes
  *
  * Full author contact details are available in file CREDITS.
  *
@@ -13,28 +14,112 @@
 #ifndef LYX_SUPPORT_UNICODE_H
 #define LYX_SUPPORT_UNICODE_H
 
-#include <boost/cstdint.hpp>
+#include "support/strfwd.h"
+#include "support/unique_ptr.h"
+
+#include <cstddef>
+#include <string>
 #include <vector>
 
-std::vector<boost::uint32_t>
-utf8_to_ucs4(std::vector<char> const & utf8str);
 
-std::vector<boost::uint32_t>
-ucs2_to_ucs4(std::vector<unsigned short> const & ucs2str);
+namespace lyx {
+
+/**
+ * Wrapper for iconv(3).
+ *
+ * According to the POSIX standard, all specified functions are thread-safe,
+ * with some exceptions. The iconv() function is not listed as an exception:
+ * http://pubs.opengroup.org/onlinepubs/9699919799/xrat/V4_xsh_chap02.html#tag_22_02_09_09
+ * http://man7.org/linux/man-pages/man7/pthreads.7.html
+ *
+ * Therefore, you can use as many instances of this class in parallel as you
+ * like. However, you need to ensure that each instance is only used by one
+ * thread at any given time. If this condition is not met you get nasty
+ * mixtures of different thread data as in bug 7240.
+ *
+ * From a performance point of view it is best to use one static instance
+ * per thread for each in/out encoding pair. This can e.g. be achieved by
+ * using helpers for thread-local storage such as QThreadStorage or
+ * boost::thread_specific_ptr. A single static instance protected by a mutex
+ * would work as well, and might be preferrable for exotic encoding pairs.
+ * Creating local IconvProcessor instances should be avoided because of the
+ * overhead in iconv_open().
+ */
+class IconvProcessor
+{
+       /// open iconv.
+       /// \return true if the processor is ready to use.
+       bool init();
+       std::string const tocode_;
+       std::string const fromcode_;
+       struct Handler;
+       unique_ptr<Handler> h_;
+public:
+       IconvProcessor(std::string tocode, std::string fromcode);
+       /// convert any data from \c fromcode to \c tocode unicode format.
+       /// \return the number of bytes of the converted output buffer.
+       int convert(char const * in_buffer, size_t in_size,
+               char * out_buffer, size_t max_out_size);
+       /// target encoding
+       std::string to() const { return tocode_; }
+       // required by g++ 4.6
+       IconvProcessor(IconvProcessor && other);
+};
+
+/// Get the global IconvProcessor instance of the current thread for
+/// utf8->ucs4 conversions
+IconvProcessor & utf8ToUcs4();
+
+// A single codepoint conversion for utf8_to_ucs4 does not make
+// sense, so that function is left out.
+
+std::vector<char_type> utf8_to_ucs4(std::vector<char> const & utf8str);
+
+std::vector<char_type> utf8_to_ucs4(char const * utf8str, size_t ls);
+
+// utf16_to_ucs4
+
+std::vector<char_type> utf16_to_ucs4(unsigned short const * s, size_t ls);
+
+// ucs4_to_utf16
+
+std::vector<unsigned short> ucs4_to_utf16(char_type const * s, size_t ls);
+
+/// Get the global IconvProcessor instance of the current thread for
+/// ucs4->utf8 conversions
+IconvProcessor & ucs4ToUtf8();
+
+// ucs4_to_utf8
+
+std::vector<char> ucs4_to_utf8(char_type c);
+
+std::vector<char> ucs4_to_utf8(std::vector<char_type> const & ucs4str);
+
+std::vector<char> ucs4_to_utf8(char_type const * ucs4str, size_t ls);
+
+/// convert \p s from encoding \p encoding to ucs4.
+/// \p encoding must be a valid iconv 8bit encoding
+std::vector<char_type>
+eightbit_to_ucs4(char const * s, size_t ls, std::string const & encoding);
+
+/// convert \p s from ucs4 to encoding \p encoding.
+/// \p encoding must be a valid iconv 8bit encoding
+std::vector<char> ucs4_to_eightbit(char_type const * ucs4str,
+       size_t ls, std::string const & encoding);
 
-std::vector<unsigned short>
-ucs4_to_ucs2(std::vector<boost::uint32_t> const & ucs4str);
+/// convert ucs4 character \p c to encoding \p encoding.
+/// \p encoding must be a valid iconv 8bit encoding
+char ucs4_to_eightbit(char_type c, std::string const & encoding);
 
-std::vector<unsigned short>
-ucs4_to_ucs2(boost::uint32_t const * s, size_t ls);
+///
+void ucs4_to_multibytes(char_type ucs4, std::vector<char> & out,
+       std::string const & encoding);
 
-unsigned short
-ucs4_to_ucs2(boost::uint32_t c);
+extern char const * ucs4_codeset;
 
-std::vector<char>
-ucs4_to_utf8(std::vector<boost::uint32_t> const & ucs4str);
+/// How many bytes does one UCS4 code point use at most in encoding \p encoding?
+int max_encoded_bytes(std::string const & encoding);
 
-std::vector<char>
-ucs4_to_utf8(boost::uint32_t c);
+} // namespace lyx
 
 #endif