Ginger88895
/
warzone2100
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

* Provide implementation of function "size_t utf8_character_count(const char* utf8_string)" which counts the amount of characters (not bytes/octects!) in a UTF-8 encoded string 

git-svn-id: svn+ssh://svn.gna.org/svn/warzone/trunk@2282 4a71c877-e1ca-e34f-864e-861f7616d084
master
Giel van Schijndel 2007-07-30 14:46:15 +00:00
parent 38a82a2ada
commit 8bbe10a748
1 changed files with 85 additions and 1 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

86
lib/framework/utf8.c
View File

@ -25,9 +25,93 @@
#include "utf8.h"
#include "debug.h"
// Assert that non-starting octets are of the form 10xxxxxx
#define ASSERT_NON_START_OCTET(octet) \
assert((octet & 0xC0) == 0x80 && "invalid non-start UTF-8 octet")
size_t utf8_character_count(const char* utf8_string)
{
// Yet to implement
const char* curChar = utf8_string;
size_t length = 0;
while (*curChar != '\0')
{
// first octect: 0xxxxxxx: 7 bit (ASCII)
if ((*curChar & 0x80) == 0x00)
{
// 1 byte long encoding
curChar += 1;
}
// first octect: 110xxxxx
else if ((*curChar & 0xe0) == 0xc0)
{
// 2 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
curChar += 2;
}
// first octect: 1110xxxx
else if ((*curChar & 0xf0) == 0xe0)
{
// 3 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
ASSERT_NON_START_OCTET(curChar[2]);
curChar += 3;
}
// first octect: 11110xxx
else if ((*curChar & 0xf8) == 0xf0)
{
// 4 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
ASSERT_NON_START_OCTET(curChar[2]);
ASSERT_NON_START_OCTET(curChar[3]);
curChar += 4;
}
// first octect: 111110xx
else if ((*curChar & 0xfc) == 0xf8)
{
// 5 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
ASSERT_NON_START_OCTET(curChar[2]);
ASSERT_NON_START_OCTET(curChar[3]);
ASSERT_NON_START_OCTET(curChar[4]);
curChar += 5;
}
// first octect: 1111110x
else if ((*curChar & 0xfe) == 0xfc)
{
// 6 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
ASSERT_NON_START_OCTET(curChar[2]);
ASSERT_NON_START_OCTET(curChar[3]);
ASSERT_NON_START_OCTET(curChar[4]);
ASSERT_NON_START_OCTET(curChar[5]);
curChar += 6;
}
// first octect: 11111110
else if ((*curChar & 0xff) == 0xfe)
{
// 7 byte long encoding
ASSERT_NON_START_OCTET(curChar[1]);
ASSERT_NON_START_OCTET(curChar[2]);
ASSERT_NON_START_OCTET(curChar[3]);
ASSERT_NON_START_OCTET(curChar[4]);
ASSERT_NON_START_OCTET(curChar[5]);
ASSERT_NON_START_OCTET(curChar[6]);
curChar += 7;
}
// first octet: 11111111
else
{
// apparently this character uses more than 36 bit
// this decoder is not developed to cope with those
// characters so error out
ASSERT(!"out-of-range UTF-8 character", "utf8_character_count: this UTF-8 character is too large (> 36bits) for this UTF-8 decoder");
}
++length;
}
return length;
}
size_t unicode_utf8_buffer_length(const uint_fast32_t* unicode_string)