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Ignore whitespace Rev 4178 → Rev 4179

/trunk/kernel/generic/src/lib/string.c
42,6 → 42,8
#include <arch.h>
#include <console/kconsole.h>
 
char invalch = '?';
 
/** Decode a single UTF-8 character from a NULL-terminated string.
*
* Decode a single UTF-8 character from a plain char NULL-terminated
51,11 → 53,12
* @param str Plain character NULL-terminated string.
* @param index Index (counted in plain characters) where to start
* the decoding.
* @param limit Maximal allowed value of index.
*
* @return Decoded character in UTF-32 or '?' if the encoding is wrong.
*
*/
wchar_t utf8_decode(const char *str, index_t *index)
wchar_t utf8_decode(const char *str, index_t *index, index_t limit)
{
uint8_t c1; /* First plain character from str */
uint8_t c2; /* Second plain character from str */
62,21 → 65,34
uint8_t c3; /* Third plain character from str */
uint8_t c4; /* Fourth plain character from str */
if (*index > limit)
return invalch;
c1 = (uint8_t) str[*index];
if ((c1 & 0x80) == 0) {
/* Plain ASCII (code points 0 .. 127) */
return (wchar_t) c1;
} else if ((c1 & 0xe0) == 0xc0) {
}
if ((c1 & 0xe0) == 0xc0) {
/* Code points 128 .. 2047 */
if (*index + 1 > limit)
return invalch;
c2 = (uint8_t) str[*index + 1];
if ((c2 & 0xc0) == 0x80) {
(*index)++;
return ((wchar_t) ((c1 & 0x1f) << 6) | (c2 & 0x3f));
} else
return ((wchar_t) '?');
} else if ((c1 & 0xf0) == 0xe0) {
return invalch;
}
if ((c1 & 0xf0) == 0xe0) {
/* Code points 2048 .. 65535 */
if (*index + 2 > limit)
return invalch;
c2 = (uint8_t) str[*index + 1];
if ((c2 & 0xc0) == 0x80) {
(*index)++;
85,11 → 101,16
(*index)++;
return ((wchar_t) ((c1 & 0x0f) << 12) | ((c2 & 0x3f) << 6) | (c3 & 0x3f));
} else
return ((wchar_t) '?');
return invalch;
} else
return ((wchar_t) '?');
} else if ((c1 & 0xf8) == 0xf0) {
return invalch;
}
if ((c1 & 0xf8) == 0xf0) {
/* Code points 65536 .. 1114111 */
if (*index + 3 > limit)
return invalch;
c2 = (uint8_t) str[*index + 1];
if ((c2 & 0xc0) == 0x80) {
(*index)++;
101,32 → 122,189
(*index)++;
return ((wchar_t) ((c1 & 0x07) << 18) | ((c2 & 0x3f) << 12) | ((c3 & 0x3f) << 6) | (c4 & 0x3f));
} else
return ((wchar_t) '?');
return invalch;
} else
return ((wchar_t) '?');
return invalch;
} else
return ((wchar_t) '?');
return invalch;
}
return ((wchar_t) '?');
return invalch;
}
 
/** Return number of characters in a string.
/** Encode a single UTF-32 character as UTF-8
*
* @param str NULL terminated string.
* Encode a single UTF-32 character as UTF-8 and store it into
* the given buffer at @index. Encoding starts at @index and
* this index is incremented if the UTF-8 character takes
* more than a single byte.
*
* @param ch Input UTF-32 character.
* @param str Output buffer.
* @param index Index (counted in plain characters) where to start
* the encoding
* @param limit Maximal allowed value of index.
*
* @return True if the character was encoded or false if there is not
* enought space in the output buffer or the character is invalid
* Unicode code point.
*
*/
bool utf8_encode(const wchar_t ch, char *str, index_t *index, index_t limit)
{
if (*index > limit)
return false;
if ((ch >= 0) && (ch <= 127)) {
/* Plain ASCII (code points 0 .. 127) */
str[*index] = ch & 0x7f;
return true;
}
if ((ch >= 128) && (ch <= 2047)) {
/* Code points 128 .. 2047 */
if (*index + 1 > limit)
return false;
str[*index] = 0xc0 | ((ch >> 6) & 0x1f);
(*index)++;
str[*index] = 0x80 | (ch & 0x3f);
return true;
}
if ((ch >= 2048) && (ch <= 65535)) {
/* Code points 2048 .. 65535 */
if (*index + 2 > limit)
return false;
str[*index] = 0xe0 | ((ch >> 12) & 0x0f);
(*index)++;
str[*index] = 0x80 | ((ch >> 6) & 0x3f);
(*index)++;
str[*index] = 0x80 | (ch & 0x3f);
return true;
}
if ((ch >= 65536) && (ch <= 1114111)) {
/* Code points 65536 .. 1114111 */
if (*index + 3 > limit)
return false;
str[*index] = 0xf0 | ((ch >> 18) & 0x07);
(*index)++;
str[*index] = 0x80 | ((ch >> 12) & 0x3f);
(*index)++;
str[*index] = 0x80 | ((ch >> 6) & 0x3f);
(*index)++;
str[*index] = 0x80 | (ch & 0x3f);
return true;
}
return false;
}
 
/** Get bytes used by UTF-8 characters.
*
* Get the number of bytes (count of plain characters) which
* are used by a given count of UTF-8 characters in a string.
* As UTF-8 encoding is multibyte, there is no constant
* correspondence between number of characters and used bytes.
*
* @param str UTF-8 string to consider.
* @param count Number of UTF-8 characters to count.
*
* @return Number of bytes used by the characters.
*
*/
size_t utf8_count_bytes(const char *str, count_t count)
{
size_t size = 0;
index_t index = 0;
while ((utf8_decode(str, &index, UTF8_NO_LIMIT) != 0) && (size < count)) {
size++;
index++;
}
return index;
}
 
/** Check whether character is plain ASCII.
*
* @return True if character is plain ASCII.
*
*/
bool ascii_check(const wchar_t ch)
{
if ((ch >= 0) && (ch <= 127))
return true;
return false;
}
 
/** Check whether character is Unicode.
*
* @return True if character is valid Unicode code point.
*
*/
bool unicode_check(const wchar_t ch)
{
if ((ch >= 0) && (ch <= 1114111))
return true;
return false;
}
 
/** Return number of plain characters in a string.
*
* @param str NULL-terminated string.
*
* @return Number of characters in str.
*
*/
size_t strlen(const char *str)
{
int i;
size_t size;
for (size = 0; str[size]; size++);
for (i = 0; str[i]; i++);
return size;
}
 
/** Return number of UTF-8 characters in a string.
*
* @param str NULL-terminated UTF-8 string.
*
* @return Number of UTF-8 characters in str.
*
*/
size_t strlen_utf8(const char *str)
{
size_t size = 0;
index_t index = 0;
return i;
while (utf8_decode(str, &index, UTF8_NO_LIMIT) != 0) {
size++;
index++;
}
return size;
}
 
/** Return number of UTF-32 characters in a string.
*
* @param str NULL-terminated UTF-32 string.
*
* @return Number of UTF-32 characters in str.
*
*/
size_t strlen_utf32(const wchar_t *str)
{
size_t size;
for (size = 0; str[size]; size++);
return size;
}
 
/** Compare two NULL terminated strings
*
* Do a char-by-char comparison of two NULL terminated strings.