mbfilter_uuencode.c [plain text]
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include "mbfilter.h"
#include "mbfilter_uuencode.h"
const mbfl_encoding mbfl_encoding_uuencode = {
mbfl_no_encoding_uuencode,
"UUENCODE",
"x-uuencode",
NULL,
NULL,
MBFL_ENCTYPE_SBCS
};
const struct mbfl_convert_vtbl vtbl_uuencode_8bit = {
mbfl_no_encoding_uuencode,
mbfl_no_encoding_8bit,
mbfl_filt_conv_common_ctor,
mbfl_filt_conv_common_dtor,
mbfl_filt_conv_uudec,
mbfl_filt_conv_common_flush
};
#define CK(statement) do { if ((statement) < 0) return (-1); } while (0)
#define UUDEC(c) (char)(((c)-' ')&077)
static const char * uuenc_begin_text = "begin ";
enum { uudec_state_ground=0, uudec_state_inbegin,
uudec_state_until_newline,
uudec_state_size, uudec_state_a, uudec_state_b, uudec_state_c, uudec_state_d,
uudec_state_skip_newline};
int mbfl_filt_conv_uudec(int c, mbfl_convert_filter * filter)
{
int n;
switch(filter->status) {
case uudec_state_ground:
if (filter->cache == 0 && c == 'b')
{
filter->status = uudec_state_inbegin;
filter->cache = 1;
}
else if (c == '\n')
filter->cache = 0;
else
filter->cache++;
break;
case uudec_state_inbegin:
if (uuenc_begin_text[filter->cache++] != c) {
filter->status = uudec_state_ground;
break;
}
if (filter->cache == 5)
{
filter->status = uudec_state_until_newline;
filter->cache = 0;
}
break;
case uudec_state_until_newline:
if (c == '\n')
filter->status = uudec_state_size;
break;
case uudec_state_size:
n = UUDEC(c);
filter->cache = n << 24;
filter->status = uudec_state_a;
break;
case uudec_state_a:
n = UUDEC(c);
filter->cache |= (n << 16);
filter->status = uudec_state_b;
break;
case uudec_state_b:
n = UUDEC(c);
filter->cache |= (n << 8);
filter->status = uudec_state_c;
break;
case uudec_state_c:
n = UUDEC(c);
filter->cache |= n;
filter->status = uudec_state_d;
break;
case uudec_state_d:
{
int A, B, C, D = UUDEC(c);
A = (filter->cache >> 16) & 0xff;
B = (filter->cache >> 8) & 0xff;
C = (filter->cache) & 0xff;
n = (filter->cache >> 24) & 0xff;
if (n-- > 0)
CK((*filter->output_function)( (A << 2) | (B >> 4), filter->data));
if (n-- > 0)
CK((*filter->output_function)( (B << 4) | (C >> 2), filter->data));
if (n-- > 0)
CK((*filter->output_function)( (C << 6) | D, filter->data));
filter->cache = n << 24;
if (n == 0)
filter->status = uudec_state_skip_newline;
else
filter->status = uudec_state_a;
}
break;
case uudec_state_skip_newline:
filter->status = uudec_state_size;
}
return c;
}