intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 65 insertions, 0 deletions

diff --git a/contrib/libs/base64/avx2/dec_tail.c b/contrib/libs/base64/avx2/dec_tail.c
new file mode 100644
index 0000000000..b472f91b33
--- /dev/null
+++ b/contrib/libs/base64/avx2/dec_tail.c
@@ -0,0 +1,65 @@
+		if (srclen-- == 0) {
+			ret = 1;
+			break;
+		}
+		if ((q = avx2_base64_table_dec[*c++]) >= 254) {
+			st.eof = 1;
+			// Treat character '=' as invalid for byte 0:
+			break;
+		}
+		st.carry = q << 2;
+		st.bytes++;
+
+	case 1:	if (srclen-- == 0) {
+			ret = 1;
+			break;
+		}
+		if ((q = avx2_base64_table_dec[*c++]) >= 254) {
+			st.eof = 1;
+			// Treat character '=' as invalid for byte 1:
+			break;
+		}
+		*o++ = st.carry | (q >> 4);
+		st.carry = q << 4;
+		st.bytes++;
+		outl++;
+
+	case 2:	if (srclen-- == 0) {
+			ret = 1;
+			break;
+		}
+		if ((q = avx2_base64_table_dec[*c++]) >= 254) {
+			st.eof = 1;
+			// When q == 254, the input char is '='. Return 1 and EOF.
+			// Technically, should check if next byte is also '=', but never mind.
+			// When q == 255, the input char is invalid. Return 0 and EOF.
+			ret = (q == 254) ? 1 : 0;
+			break;
+		}
+		*o++ = st.carry | (q >> 2);
+		st.carry = q << 6;
+		st.bytes++;
+		outl++;
+
+	case 3:	if (srclen-- == 0) {
+			ret = 1;
+			break;
+		}
+		if ((q = avx2_base64_table_dec[*c++]) >= 254) {
+			st.eof = 1;
+			// 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) ? 1 : 0;
+			break;
+		}
+		*o++ = st.carry | q;
+		st.carry = 0;
+		st.bytes = 0;
+		outl++;
+	}
+}
+state->eof = st.eof;
+state->bytes = st.bytes;
+state->carry = st.carry;
+*outlen = outl;
+return ret;