Swift
summaryrefslogtreecommitdiffstats
path: root/3rdParty/Boost/libs/detail
diff options
context:
space:
mode:
authorRemko Tronçon <git@el-tramo.be>2009-06-01 08:48:42 (GMT)
committerRemko Tronçon <git@el-tramo.be>2009-06-01 09:24:28 (GMT)
commit2812bddd81f8a1b804c7460f4e14cd0aa393d129 (patch)
treed46294f35150c4f0f43deaf2d31fceaf945ae715 /3rdParty/Boost/libs/detail
downloadswift-2812bddd81f8a1b804c7460f4e14cd0aa393d129.zip
swift-2812bddd81f8a1b804c7460f4e14cd0aa393d129.tar.bz2
Import.
Diffstat (limited to '3rdParty/Boost/libs/detail')
-rw-r--r--3rdParty/Boost/libs/detail/utf8_codecvt_facet.cpp269
1 files changed, 269 insertions, 0 deletions
diff --git a/3rdParty/Boost/libs/detail/utf8_codecvt_facet.cpp b/3rdParty/Boost/libs/detail/utf8_codecvt_facet.cpp
new file mode 100644
index 0000000..658ab6a
--- /dev/null
+++ b/3rdParty/Boost/libs/detail/utf8_codecvt_facet.cpp
@@ -0,0 +1,269 @@
+/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
+// utf8_codecvt_facet.cpp
+
+// Copyright (c) 2001 Ronald Garcia, Indiana University (garcia@osl.iu.edu)
+// Andrew Lumsdaine, Indiana University (lums@osl.iu.edu).
+// Use, modification and distribution is subject to the Boost Software
+// License, Version 1.0. (See accompanying file LICENSE_1_0.txt or copy at
+// http://www.boost.org/LICENSE_1_0.txt)
+
+// Please see the comments in <boost/detail/utf8_codecvt_facet.hpp> to
+// learn how this file should be used.
+
+#include <boost/detail/utf8_codecvt_facet.hpp>
+
+#include <cstdlib> // for multi-byte converson routines
+#include <cassert>
+
+#include <boost/limits.hpp>
+#include <boost/config.hpp>
+
+// If we don't have wstring, then Unicode support
+// is not available anyway, so we don't need to even
+// compiler this file. This also fixes the problem
+// with mingw, which can compile this file, but will
+// generate link error when building DLL.
+#ifndef BOOST_NO_STD_WSTRING
+
+BOOST_UTF8_BEGIN_NAMESPACE
+
+/////////1/////////2/////////3/////////4/////////5/////////6/////////7/////////8
+// implementation for wchar_t
+
+// Translate incoming UTF-8 into UCS-4
+std::codecvt_base::result utf8_codecvt_facet::do_in(
+ std::mbstate_t& /*state*/,
+ const char * from,
+ const char * from_end,
+ const char * & from_next,
+ wchar_t * to,
+ wchar_t * to_end,
+ wchar_t * & to_next
+) const {
+ // Basic algorithm: The first octet determines how many
+ // octets total make up the UCS-4 character. The remaining
+ // "continuing octets" all begin with "10". To convert, subtract
+ // the amount that specifies the number of octets from the first
+ // octet. Subtract 0x80 (1000 0000) from each continuing octet,
+ // then mash the whole lot together. Note that each continuing
+ // octet only uses 6 bits as unique values, so only shift by
+ // multiples of 6 to combine.
+ while (from != from_end && to != to_end) {
+
+ // Error checking on the first octet
+ if (invalid_leading_octet(*from)){
+ from_next = from;
+ to_next = to;
+ return std::codecvt_base::error;
+ }
+
+ // The first octet is adjusted by a value dependent upon
+ // the number of "continuing octets" encoding the character
+ const int cont_octet_count = get_cont_octet_count(*from);
+ const wchar_t octet1_modifier_table[] = {
+ 0x00, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc
+ };
+
+ // The unsigned char conversion is necessary in case char is
+ // signed (I learned this the hard way)
+ wchar_t ucs_result =
+ (unsigned char)(*from++) - octet1_modifier_table[cont_octet_count];
+
+ // Invariants :
+ // 1) At the start of the loop, 'i' continuing characters have been
+ // processed
+ // 2) *from points to the next continuing character to be processed.
+ int i = 0;
+ while(i != cont_octet_count && from != from_end) {
+
+ // Error checking on continuing characters
+ if (invalid_continuing_octet(*from)) {
+ from_next = from;
+ to_next = to;
+ return std::codecvt_base::error;
+ }
+
+ ucs_result *= (1 << 6);
+
+ // each continuing character has an extra (10xxxxxx)b attached to
+ // it that must be removed.
+ ucs_result += (unsigned char)(*from++) - 0x80;
+ ++i;
+ }
+
+ // If the buffer ends with an incomplete unicode character...
+ if (from == from_end && i != cont_octet_count) {
+ // rewind "from" to before the current character translation
+ from_next = from - (i+1);
+ to_next = to;
+ return std::codecvt_base::partial;
+ }
+ *to++ = ucs_result;
+ }
+ from_next = from;
+ to_next = to;
+
+ // Were we done converting or did we run out of destination space?
+ if(from == from_end) return std::codecvt_base::ok;
+ else return std::codecvt_base::partial;
+}
+
+std::codecvt_base::result utf8_codecvt_facet::do_out(
+ std::mbstate_t& /*state*/,
+ const wchar_t * from,
+ const wchar_t * from_end,
+ const wchar_t * & from_next,
+ char * to,
+ char * to_end,
+ char * & to_next
+) const
+{
+ // RG - consider merging this table with the other one
+ const wchar_t octet1_modifier_table[] = {
+ 0x00, 0xc0, 0xe0, 0xf0, 0xf8, 0xfc
+ };
+
+ wchar_t max_wchar = (std::numeric_limits<wchar_t>::max)();
+ while (from != from_end && to != to_end) {
+
+ // Check for invalid UCS-4 character
+ if (*from > max_wchar) {
+ from_next = from;
+ to_next = to;
+ return std::codecvt_base::error;
+ }
+
+ int cont_octet_count = get_cont_octet_out_count(*from);
+
+ // RG - comment this formula better
+ int shift_exponent = (cont_octet_count) * 6;
+
+ // Process the first character
+ *to++ = static_cast<char>(octet1_modifier_table[cont_octet_count] +
+ (unsigned char)(*from / (1 << shift_exponent)));
+
+ // Process the continuation characters
+ // Invariants: At the start of the loop:
+ // 1) 'i' continuing octets have been generated
+ // 2) '*to' points to the next location to place an octet
+ // 3) shift_exponent is 6 more than needed for the next octet
+ int i = 0;
+ while (i != cont_octet_count && to != to_end) {
+ shift_exponent -= 6;
+ *to++ = static_cast<char>(0x80 + ((*from / (1 << shift_exponent)) % (1 << 6)));
+ ++i;
+ }
+ // If we filled up the out buffer before encoding the character
+ if(to == to_end && i != cont_octet_count) {
+ from_next = from;
+ to_next = to - (i+1);
+ return std::codecvt_base::partial;
+ }
+ *from++;
+ }
+ from_next = from;
+ to_next = to;
+ // Were we done or did we run out of destination space
+ if(from == from_end) return std::codecvt_base::ok;
+ else return std::codecvt_base::partial;
+}
+
+// How many char objects can I process to get <= max_limit
+// wchar_t objects?
+int utf8_codecvt_facet::do_length(
+ BOOST_CODECVT_DO_LENGTH_CONST std::mbstate_t &,
+ const char * from,
+ const char * from_end,
+ std::size_t max_limit
+#if BOOST_WORKAROUND(__IBMCPP__, BOOST_TESTED_AT(600))
+) const throw()
+#else
+) const
+#endif
+{
+ // RG - this code is confusing! I need a better way to express it.
+ // and test cases.
+
+ // Invariants:
+ // 1) last_octet_count has the size of the last measured character
+ // 2) char_count holds the number of characters shown to fit
+ // within the bounds so far (no greater than max_limit)
+ // 3) from_next points to the octet 'last_octet_count' before the
+ // last measured character.
+ int last_octet_count=0;
+ std::size_t char_count = 0;
+ const char* from_next = from;
+ // Use "<" because the buffer may represent incomplete characters
+ while (from_next+last_octet_count <= from_end && char_count <= max_limit) {
+ from_next += last_octet_count;
+ last_octet_count = (get_octet_count(*from_next));
+ ++char_count;
+ }
+ return static_cast<int>(from_next-from_end);
+}
+
+unsigned int utf8_codecvt_facet::get_octet_count(
+ unsigned char lead_octet
+){
+ // if the 0-bit (MSB) is 0, then 1 character
+ if (lead_octet <= 0x7f) return 1;
+
+ // Otherwise the count number of consecutive 1 bits starting at MSB
+// assert(0xc0 <= lead_octet && lead_octet <= 0xfd);
+
+ if (0xc0 <= lead_octet && lead_octet <= 0xdf) return 2;
+ else if (0xe0 <= lead_octet && lead_octet <= 0xef) return 3;
+ else if (0xf0 <= lead_octet && lead_octet <= 0xf7) return 4;
+ else if (0xf8 <= lead_octet && lead_octet <= 0xfb) return 5;
+ else return 6;
+}
+BOOST_UTF8_END_NAMESPACE
+
+namespace {
+template<std::size_t s>
+int get_cont_octet_out_count_impl(wchar_t word){
+ if (word < 0x80) {
+ return 0;
+ }
+ if (word < 0x800) {
+ return 1;
+ }
+ return 2;
+}
+
+// note the following code will generate on some platforms where
+// wchar_t is defined as UCS2. The warnings are superfluous as
+// the specialization is never instantitiated with such compilers.
+template<>
+int get_cont_octet_out_count_impl<4>(wchar_t word){
+ if (word < 0x80) {
+ return 0;
+ }
+ if (word < 0x800) {
+ return 1;
+ }
+ if (word < 0x10000) {
+ return 2;
+ }
+ if (word < 0x200000) {
+ return 3;
+ }
+ if (word < 0x4000000) {
+ return 4;
+ }
+ return 5;
+}
+
+} // namespace anonymous
+
+BOOST_UTF8_BEGIN_NAMESPACE
+// How many "continuing octets" will be needed for this word
+// == total octets - 1.
+int utf8_codecvt_facet::get_cont_octet_out_count(
+ wchar_t word
+) const {
+ return get_cont_octet_out_count_impl<sizeof(wchar_t)>(word);
+}
+BOOST_UTF8_END_NAMESPACE
+
+#endif