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if (slen-- == 0) {
ret = 1;
break;
}
if ((q = base64_table_dec_8bit[*s++]) >= 254) {
st.eof = BASE64_EOF;
// Treat character '=' as invalid for byte 0:
break;
}
st.carry = q << 2;
st.bytes++;
// Deliberate fallthrough:
BASE64_FALLTHROUGH
case 1: if (slen-- == 0) {
ret = 1;
break;
}
if ((q = base64_table_dec_8bit[*s++]) >= 254) {
st.eof = BASE64_EOF;
// Treat character '=' as invalid for byte 1:
break;
}
*o++ = st.carry | (q >> 4);
st.carry = q << 4;
st.bytes++;
olen++;
// Deliberate fallthrough:
BASE64_FALLTHROUGH
case 2: if (slen-- == 0) {
ret = 1;
break;
}
if ((q = base64_table_dec_8bit[*s++]) >= 254) {
st.bytes++;
// When q == 254, the input char is '='.
// Check if next byte is also '=':
if (q == 254) {
if (slen-- != 0) {
st.bytes = 0;
// EOF:
st.eof = BASE64_EOF;
q = base64_table_dec_8bit[*s++];
ret = ((q == 254) && (slen == 0)) ? 1 : 0;
break;
}
else {
// Almost EOF
st.eof = BASE64_AEOF;
ret = 1;
break;
}
}
// If we get here, there was an error:
break;
}
*o++ = st.carry | (q >> 2);
st.carry = q << 6;
st.bytes++;
olen++;
// Deliberate fallthrough:
BASE64_FALLTHROUGH
case 3: if (slen-- == 0) {
ret = 1;
break;
}
if ((q = base64_table_dec_8bit[*s++]) >= 254) {
st.bytes = 0;
st.eof = BASE64_EOF;
// When q == 254, the input char is '='. Return 1 and EOF.
// When q == 255, the input char is invalid. Return 0 and EOF.
ret = ((q == 254) && (slen == 0)) ? 1 : 0;
break;
}
*o++ = st.carry | q;
st.carry = 0;
st.bytes = 0;
olen++;
}
}
state->eof = st.eof;
state->bytes = st.bytes;
state->carry = st.carry;
*outlen = olen;
return ret;
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