Evas encoding: Made the utf8 parser more robust.

In now handles more error cases in a more correct way.

SVN revision: 57090
This commit is contained in:
Tom Hacohen 2011-02-16 13:00:50 +00:00
parent 52807e1550
commit a01b8fa7ce
1 changed files with 68 additions and 126 deletions

View File

@ -1,6 +1,12 @@
#include "evas_common.h"
#include "evas_encoding.h"
/* The replacement range that will be used for bad utf8 chars. */
#define ERROR_REPLACEMENT_BASE 0xDC80
#define ERROR_REPLACEMENT_END 0xDCFF
#define IS_INVALID_BYTE(x) ((x == 192) || (x == 193) || (x >= 245))
#define IS_CONTINUATION_BYTE(x) ((x & 0xC0) == 0x80)
EAPI Eina_Unicode
evas_common_encoding_utf8_get_next(const char *buf, int *iindex)
{
@ -10,14 +16,15 @@ evas_common_encoding_utf8_get_next(const char *buf, int *iindex)
*
* Returns 0 to indicate there is no next char
*/
#if 1
/* Note: we don't currently handle overlong forms and some other
* broken cases. */
int index = *iindex;
Eina_Unicode r;
unsigned char d;
/* if this char is the null terminator, exit */
if ((d = buf[index++]) == 0) return 0;
if ((d & 0x80) == 0)
{ // 1 byte (7bit) - 0xxxxxxx
*iindex = index;
@ -26,150 +33,91 @@ evas_common_encoding_utf8_get_next(const char *buf, int *iindex)
if ((d & 0xe0) == 0xc0)
{ // 2 byte (11bit) - 110xxxxx 10xxxxxx
r = (d & 0x1f) << 6;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f);
if (!r) return 0;
if (!r) goto error;
*iindex = index;
return r;
}
if ((d & 0xf0) == 0xe0)
{ // 3 byte (16bit) - 1110xxxx 10xxxxxx 10xxxxxx
r = (d & 0x0f) << 12;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 6;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f);
if (!r) return 0;
if (!r) goto error;
*iindex = index;
return r;
}
if ((d & 0xf8) == 0xf0)
{ // 4 byte (21bit) - 11110xxx 10xxxxxx 10xxxxxx 10xxxxxx
r = (d & 0x07) << 18;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 12;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 6;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f);
if (!r) return 0;
if (!r) goto error;
*iindex = index;
return r;
}
if ((d & 0xfc) == 0xf8)
{ // 5 byte (26bit) - 111110xx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
r = (d & 0x03) << 24;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 18;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 12;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 6;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f);
if (!r) return 0;
if (!r) goto error;
*iindex = index;
return r;
}
if ((d & 0xfe) == 0xfc)
{ // 6 byte (31bit) - 1111110x 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx 10xxxxxx
r = (d & 0x01) << 30;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 24;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 18;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 12;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f) << 6;
if ((d = buf[index++]) == 0) return 0;
if (((d = buf[index++]) == 0) || IS_INVALID_BYTE(d) ||
!IS_CONTINUATION_BYTE(d)) goto error;
r |= (d & 0x3f);
if (!r) return 0;
if (!r) goto error;
*iindex = index;
return r;
}
return 0;
#else
int index = *iindex, r, len;
unsigned char d, d2, d3, d4;
/* if this char is the null terminator, exit */
if (!buf[index]) return 0;
d = buf[index++];
while (buf[index] && ((buf[index] & 0xc0) == 0x80))
index++;
len = index - *iindex;
if (len == 1)
r = d;
else if (len == 2)
{
/* 2 bytes */
d2 = buf[*iindex + 1];
if (d2 == 0)
{
*iindex = *iindex + 1;
return 0;
}
r = d & 0x1f; /* copy lower 5 */
r <<= 6;
r |= (d2 & 0x3f); /* copy lower 6 */
}
else if (len == 3)
{
/* 3 bytes */
d2 = buf[*iindex + 1];
if (d2 == 0)
{
*iindex = *iindex + 1;
return 0;
}
d3 = buf[*iindex + 2];
if (d3 == 0)
{
*iindex = *iindex + 2;
return 0;
}
r = d & 0x0f; /* copy lower 4 */
r <<= 6;
r |= (d2 & 0x3f);
r <<= 6;
r |= (d3 & 0x3f);
}
else
{
/* 4 bytes */
d2 = buf[*iindex + 1];
if (d2 == 0)
{
*iindex = *iindex + 1;
return 0;
}
d3 = buf[*iindex + 2];
if (d3 == 0)
{
*iindex = *iindex + 2;
return 0;
}
d4 = buf[*iindex + 3];
if (d4 == 0)
{
*iindex = *iindex + 3;
return 0;
}
r = d & 0x0f; /* copy lower 4 */
r <<= 6;
r |= (d2 & 0x3f);
r <<= 6;
r |= (d3 & 0x3f);
r <<= 6;
r |= (d4 & 0x3f);
}
*iindex = index;
return r;
#endif
/* Gets here where there was an error and we want to replace the char
* we just use the invalid unicode codepoints 8 lower bits represent
* the original char */
error:
d = buf[*iindex];
(*iindex)++;
return ERROR_REPLACEMENT_BASE | d;
}
EAPI Eina_Unicode
@ -211,25 +159,9 @@ evas_common_encoding_utf8_get_last(const char *buf, int buflen)
*
* Returns -1 to indicate an error
*/
int index;
unsigned char d;
if (buflen < 1) return 0;
index = buflen - 1;
d = buf[index];
if (!(d & 0x80))
return index;
else
{
while (index > 0)
{
index--;
d = buf[index];
if ((d & 0xc0) != 0x80)
return index;
}
}
return 0;
/* Go one character backwards and then return the char at the new place */
evas_common_encoding_utf8_get_prev(buf, &buflen);
return evas_common_encoding_utf8_get_next(buf, &buflen);
}
EAPI int
@ -293,10 +225,20 @@ evas_common_encoding_unicode_to_utf8(const Eina_Unicode *uni, int *_len)
}
else if (*uind <= 0xFFFF) /* 3 byte char */
{
*ind++ = 0xE0 | (unsigned char) (*uind >> 12);
*ind++ = 0x80 | (unsigned char) ((*uind >> 6) & 0x3F);
*ind++ = 0x80 | (unsigned char) (*uind & 0x3F);
len += 3;
/* If it's a special replacement codepoint */
if (*uind >= ERROR_REPLACEMENT_BASE &&
*uind <= ERROR_REPLACEMENT_END)
{
*ind++ = *uind && 0xFF;
len += 1;
}
else
{
*ind++ = 0xE0 | (unsigned char) (*uind >> 12);
*ind++ = 0x80 | (unsigned char) ((*uind >> 6) & 0x3F);
*ind++ = 0x80 | (unsigned char) (*uind & 0x3F);
len += 3;
}
}
else /* 4 byte char */
{