Replace FastReadBuffer object with a struct+inline functions

Author: 1st1

buffer.pxd

@@ -142,44 +142,3 @@ cdef class ReadBuffer:
 
     @staticmethod
     cdef ReadBuffer new_message_parser(object data)
-
-
-@cython.no_gc_clear
-@cython.final
-@cython.freelist(_BUFFER_FREELIST_SIZE)
-cdef class FastReadBuffer:
-
-    cdef:
-        const char* buf
-        ssize_t len
-
-    cdef inline const char* read(self, ssize_t n) except NULL:
-        cdef const char *result
-
-        if n > self.len:
-            self._raise_ins_err(n, self.len)
-
-        result = self.buf
-        self.buf += n
-        self.len -= n
-
-        return result
-
-    cdef inline const char* read_all(self):
-        cdef const char *result
-        result = self.buf
-        self.buf += self.len
-        self.len = 0
-        return result
-
-    cdef inline FastReadBuffer slice_from(self, FastReadBuffer source,
-                                          ssize_t len):
-        self.buf = source.read(len)
-        self.len = len
-        return self
-
-    cdef _raise_ins_err(self, ssize_t n, ssize_t len)
-
-    @staticmethod
-    cdef inline FastReadBuffer new():
-        return FastReadBuffer.__new__(FastReadBuffer)

buffer.pyx

@@ -658,14 +658,3 @@ cdef class ReadBuffer:
         buf._current_message_len_unread = buf._len0
 
         return buf
-
-
-@cython.no_gc_clear
-@cython.final
-@cython.freelist(_BUFFER_FREELIST_SIZE)
-cdef class FastReadBuffer:
-
-    cdef _raise_ins_err(self, ssize_t n, ssize_t len):
-        raise exceptions.BufferError(
-            'insufficient data in buffer: requested {}, remaining {}'.
-                format(n, self.len))

codecs/__init__.pxd

@@ -16,128 +16,128 @@ ctypedef object (*encode_func)(CodecContext settings,
                                object obj)
 
 ctypedef object (*decode_func)(CodecContext settings,
-                               FastReadBuffer buf)
+                               FRBuffer *buf)
 
 
 # Datetime
 cdef date_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef date_decode(CodecContext settings, FastReadBuffer buf)
+cdef date_decode(CodecContext settings, FRBuffer * buf)
 cdef date_encode_tuple(CodecContext settings, WriteBuffer buf, obj)
-cdef date_decode_tuple(CodecContext settings, FastReadBuffer buf)
+cdef date_decode_tuple(CodecContext settings, FRBuffer * buf)
 cdef timestamp_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef timestamp_decode(CodecContext settings, FastReadBuffer buf)
+cdef timestamp_decode(CodecContext settings, FRBuffer * buf)
 cdef timestamp_encode_tuple(CodecContext settings, WriteBuffer buf, obj)
-cdef timestamp_decode_tuple(CodecContext settings, FastReadBuffer buf)
+cdef timestamp_decode_tuple(CodecContext settings, FRBuffer * buf)
 cdef timestamptz_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef timestamptz_decode(CodecContext settings, FastReadBuffer buf)
+cdef timestamptz_decode(CodecContext settings, FRBuffer * buf)
 cdef time_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef time_decode(CodecContext settings, FastReadBuffer buf)
+cdef time_decode(CodecContext settings, FRBuffer * buf)
 cdef time_encode_tuple(CodecContext settings, WriteBuffer buf, obj)
-cdef time_decode_tuple(CodecContext settings, FastReadBuffer buf)
+cdef time_decode_tuple(CodecContext settings, FRBuffer * buf)
 cdef timetz_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef timetz_decode(CodecContext settings, FastReadBuffer buf)
+cdef timetz_decode(CodecContext settings, FRBuffer * buf)
 cdef timetz_encode_tuple(CodecContext settings, WriteBuffer buf, obj)
-cdef timetz_decode_tuple(CodecContext settings, FastReadBuffer buf)
+cdef timetz_decode_tuple(CodecContext settings, FRBuffer * buf)
 cdef interval_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef interval_decode(CodecContext settings, FastReadBuffer buf)
+cdef interval_decode(CodecContext settings, FRBuffer * buf)
 cdef interval_encode_tuple(CodecContext settings, WriteBuffer buf, tuple obj)
-cdef interval_decode_tuple(CodecContext settings, FastReadBuffer buf)
+cdef interval_decode_tuple(CodecContext settings, FRBuffer * buf)
 
 
 # Bits
 cdef bits_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef bits_decode(CodecContext settings, FastReadBuffer buf)
+cdef bits_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Bools
 cdef bool_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef bool_decode(CodecContext settings, FastReadBuffer buf)
+cdef bool_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Geometry
 cdef box_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef box_decode(CodecContext settings, FastReadBuffer buf)
+cdef box_decode(CodecContext settings, FRBuffer * buf)
 cdef line_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef line_decode(CodecContext settings, FastReadBuffer buf)
+cdef line_decode(CodecContext settings, FRBuffer * buf)
 cdef lseg_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef lseg_decode(CodecContext settings, FastReadBuffer buf)
+cdef lseg_decode(CodecContext settings, FRBuffer * buf)
 cdef point_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef point_decode(CodecContext settings, FastReadBuffer buf)
+cdef point_decode(CodecContext settings, FRBuffer * buf)
 cdef path_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef path_decode(CodecContext settings, FastReadBuffer buf)
+cdef path_decode(CodecContext settings, FRBuffer * buf)
 cdef poly_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef poly_decode(CodecContext settings, FastReadBuffer buf)
+cdef poly_decode(CodecContext settings, FRBuffer * buf)
 cdef circle_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef circle_decode(CodecContext settings, FastReadBuffer buf)
+cdef circle_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Hstore
 cdef hstore_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef hstore_decode(CodecContext settings, FastReadBuffer buf)
+cdef hstore_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Ints
 cdef int2_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef int2_decode(CodecContext settings, FastReadBuffer buf)
+cdef int2_decode(CodecContext settings, FRBuffer * buf)
 cdef int4_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef int4_decode(CodecContext settings, FastReadBuffer buf)
+cdef int4_decode(CodecContext settings, FRBuffer * buf)
 cdef uint4_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef uint4_decode(CodecContext settings, FastReadBuffer buf)
+cdef uint4_decode(CodecContext settings, FRBuffer * buf)
 cdef int8_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef int8_decode(CodecContext settings, FastReadBuffer buf)
+cdef int8_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Floats
 cdef float4_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef float4_decode(CodecContext settings, FastReadBuffer buf)
+cdef float4_decode(CodecContext settings, FRBuffer * buf)
 cdef float8_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef float8_decode(CodecContext settings, FastReadBuffer buf)
+cdef float8_decode(CodecContext settings, FRBuffer * buf)
 
 
 # JSON
 cdef jsonb_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef jsonb_decode(CodecContext settings, FastReadBuffer buf)
+cdef jsonb_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Text
 cdef as_pg_string_and_size(
         CodecContext settings, obj, char **cstr, ssize_t *size)
 cdef text_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef text_decode(CodecContext settings, FastReadBuffer buf)
+cdef text_decode(CodecContext settings, FRBuffer * buf)
 
 # Bytea
 cdef bytea_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef bytea_decode(CodecContext settings, FastReadBuffer buf)
+cdef bytea_decode(CodecContext settings, FRBuffer * buf)
 
 
 # UUID
 cdef uuid_encode(CodecContext settings, WriteBuffer wbuf, obj)
-cdef uuid_decode(CodecContext settings, FastReadBuffer buf)
+cdef uuid_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Numeric
 cdef numeric_encode_text(CodecContext settings, WriteBuffer buf, obj)
-cdef numeric_decode_text(CodecContext settings, FastReadBuffer buf)
+cdef numeric_decode_text(CodecContext settings, FRBuffer * buf)
 cdef numeric_encode_binary(CodecContext settings, WriteBuffer buf, obj)
-cdef numeric_decode_binary(CodecContext settings, FastReadBuffer buf)
+cdef numeric_decode_binary(CodecContext settings, FRBuffer * buf)
 
 
 # Void
 cdef void_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef void_decode(CodecContext settings, FastReadBuffer buf)
+cdef void_decode(CodecContext settings, FRBuffer * buf)
 
 
 # tid
 cdef tid_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef tid_decode(CodecContext settings, FastReadBuffer buf)
+cdef tid_decode(CodecContext settings, FRBuffer * buf)
 
 
 # Network
-cdef net_decode(CodecContext settings, FastReadBuffer buf)
+cdef net_decode(CodecContext settings, FRBuffer * buf)
 cdef cidr_encode(CodecContext settings, WriteBuffer buf, obj)
 cdef inet_encode(CodecContext settings, WriteBuffer buf, obj)
 
 
 # txid
 cdef txid_snapshot_encode(CodecContext settings, WriteBuffer buf, obj)
-cdef txid_snapshot_decode(CodecContext settings, FastReadBuffer buf)
+cdef txid_snapshot_decode(CodecContext settings, FRBuffer * buf)

codecs/bits.pyx

@@ -41,10 +41,10 @@ cdef bits_encode(CodecContext settings, WriteBuffer wbuf, obj):
             cpython.PyBuffer_Release(&pybuf)
 
 
-cdef bits_decode(CodecContext settings, FastReadBuffer buf):
+cdef bits_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        int32_t bitlen = hton.unpack_int32(buf.read(4))
+        int32_t bitlen = hton.unpack_int32(frb_read(buf, 4))
         ssize_t buf_len = buf.len
 
-    bytes_ = cpython.PyBytes_FromStringAndSize(buf.read_all(), buf_len)
+    bytes_ = cpython.PyBytes_FromStringAndSize(frb_read_all(buf), buf_len)
     return BitString.frombytes(bytes_, bitlen)

codecs/bytea.pyx

@@ -29,6 +29,6 @@ cdef bytea_encode(CodecContext settings, WriteBuffer wbuf, obj):
             cpython.PyBuffer_Release(&pybuf)
 
 
-cdef bytea_decode(CodecContext settings, FastReadBuffer buf):
+cdef bytea_decode(CodecContext settings, FRBuffer *buf):
     cdef ssize_t buf_len = buf.len
-    return cpython.PyBytes_FromStringAndSize(buf.read_all(), buf_len)
+    return cpython.PyBytes_FromStringAndSize(frb_read_all(buf), buf_len)

codecs/datetime.pyx

@@ -78,9 +78,9 @@ cdef inline _encode_time(WriteBuffer buf, int64_t seconds,
         buf.write_int64(ts)
 
 
-cdef inline int32_t _decode_time(FastReadBuffer buf, int64_t *seconds,
+cdef inline int32_t _decode_time(FRBuffer *buf, int64_t *seconds,
                                  int32_t *microseconds):
-    cdef int64_t ts = hton.unpack_int64(buf.read(8))
+    cdef int64_t ts = hton.unpack_int64(frb_read(buf, 8))
 
     if ts == pg_time64_infinity:
         return 1
@@ -122,8 +122,8 @@ cdef date_encode_tuple(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int32(pg_ordinal)
 
 
-cdef date_decode(CodecContext settings, FastReadBuffer buf):
-    cdef int32_t pg_ordinal = hton.unpack_int32(buf.read(4))
+cdef date_decode(CodecContext settings, FRBuffer *buf):
+    cdef int32_t pg_ordinal = hton.unpack_int32(frb_read(buf, 4))
 
     if pg_ordinal == pg_date_infinity:
         return infinity_date
@@ -133,8 +133,8 @@ cdef date_decode(CodecContext settings, FastReadBuffer buf):
         return date_from_ordinal(pg_ordinal + pg_date_offset_ord)
 
 
-cdef date_decode_tuple(CodecContext settings, FastReadBuffer buf):
-    cdef int32_t pg_ordinal = hton.unpack_int32(buf.read(4))
+cdef date_decode_tuple(CodecContext settings, FRBuffer *buf):
+    cdef int32_t pg_ordinal = hton.unpack_int32(frb_read(buf, 4))
 
     return (pg_ordinal,)
 
@@ -175,7 +175,7 @@ cdef timestamp_encode_tuple(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int64(microseconds)
 
 
-cdef timestamp_decode(CodecContext settings, FastReadBuffer buf):
+cdef timestamp_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         int64_t seconds = 0
         int32_t microseconds = 0
@@ -192,9 +192,9 @@ cdef timestamp_decode(CodecContext settings, FastReadBuffer buf):
             timedelta(0, seconds, microseconds))
 
 
-cdef timestamp_decode_tuple(CodecContext settings, FastReadBuffer buf):
+cdef timestamp_decode_tuple(CodecContext settings, FRBuffer *buf):
     cdef:
-        int64_t ts = hton.unpack_int64(buf.read(8))
+        int64_t ts = hton.unpack_int64(frb_read(buf, 8))
 
     return (ts,)
 
@@ -236,7 +236,7 @@ cdef timestamptz_encode(CodecContext settings, WriteBuffer buf, obj):
     _encode_time(buf, seconds, microseconds)
 
 
-cdef timestamptz_decode(CodecContext settings, FastReadBuffer buf):
+cdef timestamptz_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         int64_t seconds = 0
         int32_t microseconds = 0
@@ -279,7 +279,7 @@ cdef time_encode_tuple(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int64(microseconds)
 
 
-cdef time_decode(CodecContext settings, FastReadBuffer buf):
+cdef time_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         int64_t seconds = 0
         int32_t microseconds = 0
@@ -295,9 +295,9 @@ cdef time_decode(CodecContext settings, FastReadBuffer buf):
     return datetime.time(hours, min, sec, microseconds)
 
 
-cdef time_decode_tuple(CodecContext settings, FastReadBuffer buf):
+cdef time_decode_tuple(CodecContext settings, FRBuffer *buf):
     cdef:
-        int64_t ts = hton.unpack_int64(buf.read(8))
+        int64_t ts = hton.unpack_int64(frb_read(buf, 8))
 
     return (ts,)
 
@@ -342,17 +342,17 @@ cdef timetz_encode_tuple(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int32(offset_sec)
 
 
-cdef timetz_decode(CodecContext settings, FastReadBuffer buf):
+cdef timetz_decode(CodecContext settings, FRBuffer *buf):
     time = time_decode(settings, buf)
-    cdef int32_t offset = <int32_t>(hton.unpack_int32(buf.read(4)) / 60)
+    cdef int32_t offset = <int32_t>(hton.unpack_int32(frb_read(buf, 4)) / 60)
     # See the comment in the `timetz_encode` method.
     return time.replace(tzinfo=datetime.timezone(timedelta(minutes=-offset)))
 
 
-cdef timetz_decode_tuple(CodecContext settings, FastReadBuffer buf):
+cdef timetz_decode_tuple(CodecContext settings, FRBuffer *buf):
     cdef:
-        int64_t microseconds = hton.unpack_int64(buf.read(8))
-        int32_t offset_sec = hton.unpack_int32(buf.read(4))
+        int64_t microseconds = hton.unpack_int64(frb_read(buf, 8))
+        int32_t offset_sec = hton.unpack_int32(frb_read(buf, 4))
 
     return (microseconds, offset_sec)
 
@@ -391,7 +391,7 @@ cdef interval_encode_tuple(CodecContext settings, WriteBuffer buf,
     buf.write_int32(months)
 
 
-cdef interval_decode(CodecContext settings, FastReadBuffer buf):
+cdef interval_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         int32_t days
         int32_t months
@@ -401,8 +401,8 @@ cdef interval_decode(CodecContext settings, FastReadBuffer buf):
 
     _decode_time(buf, &seconds, &microseconds)
 
-    days = hton.unpack_int32(buf.read(4))
-    months = hton.unpack_int32(buf.read(4))
+    days = hton.unpack_int32(frb_read(buf, 4))
+    months = hton.unpack_int32(frb_read(buf, 4))
 
     if months < 0:
         years = -<int32_t>(-months // 12)
@@ -415,14 +415,14 @@ cdef interval_decode(CodecContext settings, FastReadBuffer buf):
                               seconds=seconds, microseconds=microseconds)
 
 
-cdef interval_decode_tuple(CodecContext settings, FastReadBuffer buf):
+cdef interval_decode_tuple(CodecContext settings, FRBuffer *buf):
     cdef:
         int32_t days
         int32_t months
         int64_t microseconds
 
-    microseconds = hton.unpack_int64(buf.read(8))
-    days = hton.unpack_int32(buf.read(4))
-    months = hton.unpack_int32(buf.read(4))
+    microseconds = hton.unpack_int64(frb_read(buf, 8))
+    days = hton.unpack_int32(frb_read(buf, 4))
+    months = hton.unpack_int32(frb_read(buf, 4))
 
     return (months, days, microseconds)

codecs/float.pyx

@@ -18,8 +18,8 @@ cdef float4_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_float(fval)
 
 
-cdef float4_decode(CodecContext settings, FastReadBuffer buf):
-    cdef float f = hton.unpack_float(buf.read(4))
+cdef float4_decode(CodecContext settings, FRBuffer *buf):
+    cdef float f = hton.unpack_float(frb_read(buf, 4))
     return cpython.PyFloat_FromDouble(f)
 
 
@@ -29,6 +29,6 @@ cdef float8_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_double(dval)
 
 
-cdef float8_decode(CodecContext settings, FastReadBuffer buf):
-    cdef double f = hton.unpack_double(buf.read(8))
+cdef float8_decode(CodecContext settings, FRBuffer *buf):
+    cdef double f = hton.unpack_double(frb_read(buf, 8))
     return cpython.PyFloat_FromDouble(f)

codecs/geometry.pyx

@@ -16,18 +16,18 @@ cdef inline _encode_points(WriteBuffer wbuf, object points):
         wbuf.write_double(point[1])
 
 
-cdef inline _decode_points(FastReadBuffer buf):
+cdef inline _decode_points(FRBuffer *buf):
     cdef:
-        int32_t npts = hton.unpack_int32(buf.read(4))
+        int32_t npts = hton.unpack_int32(frb_read(buf, 4))
         pts = cpython.PyTuple_New(npts)
         int32_t i
         object point
         double x
         double y
 
     for i in range(npts):
-        x = hton.unpack_double(buf.read(8))
-        y = hton.unpack_double(buf.read(8))
+        x = hton.unpack_double(frb_read(buf, 8))
+        y = hton.unpack_double(frb_read(buf, 8))
         point = Point(x, y)
         cpython.Py_INCREF(point)
         cpython.PyTuple_SET_ITEM(pts, i, point)
@@ -40,12 +40,12 @@ cdef box_encode(CodecContext settings, WriteBuffer wbuf, obj):
     _encode_points(wbuf, (obj[0], obj[1]))
 
 
-cdef box_decode(CodecContext settings, FastReadBuffer buf):
+cdef box_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        double high_x = hton.unpack_double(buf.read(8))
-        double high_y = hton.unpack_double(buf.read(8))
-        double low_x = hton.unpack_double(buf.read(8))
-        double low_y = hton.unpack_double(buf.read(8))
+        double high_x = hton.unpack_double(frb_read(buf, 8))
+        double high_y = hton.unpack_double(frb_read(buf, 8))
+        double low_x = hton.unpack_double(frb_read(buf, 8))
+        double low_y = hton.unpack_double(frb_read(buf, 8))
 
     return Box(Point(high_x, high_y), Point(low_x, low_y))
 
@@ -57,11 +57,11 @@ cdef line_encode(CodecContext settings, WriteBuffer wbuf, obj):
     wbuf.write_double(obj[2])
 
 
-cdef line_decode(CodecContext settings, FastReadBuffer buf):
+cdef line_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        double A = hton.unpack_double(buf.read(8))
-        double B = hton.unpack_double(buf.read(8))
-        double C = hton.unpack_double(buf.read(8))
+        double A = hton.unpack_double(frb_read(buf, 8))
+        double B = hton.unpack_double(frb_read(buf, 8))
+        double C = hton.unpack_double(frb_read(buf, 8))
 
     return Line(A, B, C)
 
@@ -71,12 +71,12 @@ cdef lseg_encode(CodecContext settings, WriteBuffer wbuf, obj):
     _encode_points(wbuf, (obj[0], obj[1]))
 
 
-cdef lseg_decode(CodecContext settings, FastReadBuffer buf):
+cdef lseg_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        double p1_x = hton.unpack_double(buf.read(8))
-        double p1_y = hton.unpack_double(buf.read(8))
-        double p2_x = hton.unpack_double(buf.read(8))
-        double p2_y = hton.unpack_double(buf.read(8))
+        double p1_x = hton.unpack_double(frb_read(buf, 8))
+        double p1_y = hton.unpack_double(frb_read(buf, 8))
+        double p2_x = hton.unpack_double(frb_read(buf, 8))
+        double p2_y = hton.unpack_double(frb_read(buf, 8))
 
     return LineSegment((p1_x, p1_y), (p2_x, p2_y))
 
@@ -87,10 +87,10 @@ cdef point_encode(CodecContext settings, WriteBuffer wbuf, obj):
     wbuf.write_double(obj[1])
 
 
-cdef point_decode(CodecContext settings, FastReadBuffer buf):
+cdef point_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        double x = hton.unpack_double(buf.read(8))
-        double y = hton.unpack_double(buf.read(8))
+        double x = hton.unpack_double(frb_read(buf, 8))
+        double y = hton.unpack_double(frb_read(buf, 8))
 
     return Point(x, y)
 
@@ -121,9 +121,9 @@ cdef path_encode(CodecContext settings, WriteBuffer wbuf, obj):
     _encode_points(wbuf, obj)
 
 
-cdef path_decode(CodecContext settings, FastReadBuffer buf):
+cdef path_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        int8_t is_closed = <int8_t>buf.read(1)[0]
+        int8_t is_closed = <int8_t>(frb_read(buf, 1)[0])
 
     return Path(*_decode_points(buf), is_closed=is_closed == 1)
 
@@ -145,7 +145,7 @@ cdef poly_encode(CodecContext settings, WriteBuffer wbuf, obj):
     _encode_points(wbuf, obj)
 
 
-cdef poly_decode(CodecContext settings, FastReadBuffer buf):
+cdef poly_decode(CodecContext settings, FRBuffer *buf):
     return Polygon(*_decode_points(buf))
 
 
@@ -156,10 +156,10 @@ cdef circle_encode(CodecContext settings, WriteBuffer wbuf, obj):
     wbuf.write_double(obj[1])
 
 
-cdef circle_decode(CodecContext settings, FastReadBuffer buf):
+cdef circle_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        double center_x = hton.unpack_double(buf.read(8))
-        double center_y = hton.unpack_double(buf.read(8))
-        double radius = hton.unpack_double(buf.read(8))
+        double center_x = hton.unpack_double(frb_read(buf, 8))
+        double center_y = hton.unpack_double(frb_read(buf, 8))
+        double radius = hton.unpack_double(frb_read(buf, 8))
 
     return Circle((center_x, center_y), radius)

codecs/hstore.pyx

@@ -40,7 +40,7 @@ cdef hstore_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_buffer(item_buf)
 
 
-cdef hstore_decode(CodecContext settings, FastReadBuffer buf):
+cdef hstore_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         dict result
         uint32_t elem_count
@@ -51,22 +51,22 @@ cdef hstore_decode(CodecContext settings, FastReadBuffer buf):
 
     result = {}
 
-    elem_count = <uint32_t>hton.unpack_int32(buf.read(4))
+    elem_count = <uint32_t>hton.unpack_int32(frb_read(buf, 4))
     if elem_count == 0:
         return result
 
     for i in range(elem_count):
-        elem_len = hton.unpack_int32(buf.read(4))
+        elem_len = hton.unpack_int32(frb_read(buf, 4))
         if elem_len < 0:
             raise ValueError('null value not allowed in hstore key')
 
-        k = decode_pg_string(settings, buf.read(elem_len), elem_len)
+        k = decode_pg_string(settings, frb_read(buf, elem_len), elem_len)
 
-        elem_len = hton.unpack_int32(buf.read(4))
+        elem_len = hton.unpack_int32(frb_read(buf, 4))
         if elem_len < 0:
             v = None
         else:
-            v = decode_pg_string(settings, buf.read(elem_len), elem_len)
+            v = decode_pg_string(settings, frb_read(buf, elem_len), elem_len)
 
         result[k] = v
 

codecs/int.pyx

@@ -14,8 +14,8 @@ cdef bool_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_byte(b'\x01' if obj is True else b'\x00')
 
 
-cdef bool_decode(CodecContext settings, FastReadBuffer buf):
-    return buf.read(1)[0] is b'\x01'
+cdef bool_decode(CodecContext settings, FRBuffer *buf):
+    return frb_read(buf, 1)[0] is b'\x01'
 
 
 cdef int2_encode(CodecContext settings, WriteBuffer buf, obj):
@@ -34,8 +34,8 @@ cdef int2_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int16(<int16_t>val)
 
 
-cdef int2_decode(CodecContext settings, FastReadBuffer buf):
-    return cpython.PyLong_FromLong(hton.unpack_int16(buf.read(2)))
+cdef int2_decode(CodecContext settings, FRBuffer *buf):
+    return cpython.PyLong_FromLong(hton.unpack_int16(frb_read(buf, 2)))
 
 
 cdef int4_encode(CodecContext settings, WriteBuffer buf, obj):
@@ -55,8 +55,8 @@ cdef int4_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int32(<int32_t>val)
 
 
-cdef int4_decode(CodecContext settings, FastReadBuffer buf):
-    return cpython.PyLong_FromLong(hton.unpack_int32(buf.read(4)))
+cdef int4_decode(CodecContext settings, FRBuffer *buf):
+    return cpython.PyLong_FromLong(hton.unpack_int32(frb_read(buf, 4)))
 
 
 cdef uint4_encode(CodecContext settings, WriteBuffer buf, obj):
@@ -76,9 +76,9 @@ cdef uint4_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int32(<int32_t>val)
 
 
-cdef uint4_decode(CodecContext settings, FastReadBuffer buf):
+cdef uint4_decode(CodecContext settings, FRBuffer *buf):
     return cpython.PyLong_FromUnsignedLong(
-        <uint32_t>hton.unpack_int32(buf.read(4)))
+        <uint32_t>hton.unpack_int32(frb_read(buf, 4)))
 
 
 cdef int8_encode(CodecContext settings, WriteBuffer buf, obj):
@@ -98,5 +98,5 @@ cdef int8_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int64(<int64_t>val)
 
 
-cdef int8_decode(CodecContext settings, FastReadBuffer buf):
-    return cpython.PyLong_FromLongLong(hton.unpack_int64(buf.read(8)))
+cdef int8_decode(CodecContext settings, FRBuffer *buf):
+    return cpython.PyLong_FromLongLong(hton.unpack_int64(frb_read(buf, 8)))

codecs/json.pyx

@@ -20,8 +20,8 @@ cdef jsonb_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_cstr(str, size)
 
 
-cdef jsonb_decode(CodecContext settings, FastReadBuffer buf):
-    cdef uint8_t format = <uint8_t>buf.read(1)[0]
+cdef jsonb_decode(CodecContext settings, FRBuffer *buf):
+    cdef uint8_t format = <uint8_t>(frb_read(buf, 1)[0])
 
     if format != 1:
         raise ValueError('unexpected JSONB format: {}'.format(format))

codecs/misc.pyx

@@ -10,7 +10,7 @@ cdef void_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int32(0)
 
 
-cdef void_decode(CodecContext settings, FastReadBuffer buf):
+cdef void_decode(CodecContext settings, FRBuffer *buf):
     # Do nothing; void will be passed as NULL so this function
     # will never be called.
     pass

codecs/network.pyx

@@ -59,12 +59,12 @@ cdef inline _net_encode(WriteBuffer buf, int8_t family, uint32_t bits,
     buf.write_cstr(addrbytes, addrlen)
 
 
-cdef net_decode(CodecContext settings, FastReadBuffer buf):
+cdef net_decode(CodecContext settings, FRBuffer *buf):
     cdef:
-        int32_t family = <int32_t>buf.read(1)[0]
-        uint8_t bits = <uint8_t>buf.read(1)[0]
-        int32_t is_cidr = <int32_t>buf.read(1)[0]
-        int32_t addrlen = <int32_t>buf.read(1)[0]
+        int32_t family = <int32_t>frb_read(buf, 1)[0]
+        uint8_t bits = <uint8_t>frb_read(buf, 1)[0]
+        int32_t is_cidr = <int32_t>frb_read(buf, 1)[0]
+        int32_t addrlen = <int32_t>frb_read(buf, 1)[0]
         bytes addr
         uint8_t max_prefix_len = _ip_max_prefix_len(family)
 
@@ -85,7 +85,7 @@ cdef net_decode(CodecContext settings, FastReadBuffer buf):
             'cidr' if is_cidr else 'inet'
         ))
 
-    addr = cpython.PyBytes_FromStringAndSize(buf.read(addrlen), addrlen)
+    addr = cpython.PyBytes_FromStringAndSize(frb_read(buf, addrlen), addrlen)
 
     if is_cidr or bits != max_prefix_len:
         return _ipnet(addr).supernet(new_prefix=cpython.PyLong_FromLong(bits))

codecs/numeric.pyx

@@ -24,7 +24,7 @@ cdef numeric_encode_text(CodecContext settings, WriteBuffer buf, obj):
     text_encode(settings, buf, str(obj))
 
 
-cdef numeric_decode_text(CodecContext settings, FastReadBuffer buf):
+cdef numeric_decode_text(CodecContext settings, FRBuffer *buf):
     return _Dec(text_decode(settings, buf))
 
 
@@ -129,12 +129,12 @@ cdef numeric_encode_binary(CodecContext settings, WriteBuffer buf, obj):
 # For this reason the below code is pure overhead and is ~25% slower
 # than the simple text decoder above.  That said, we need the binary
 # decoder to support binary COPY with numeric values.
-cdef numeric_decode_binary(CodecContext settings, FastReadBuffer buf):
+cdef numeric_decode_binary(CodecContext settings, FRBuffer *buf):
     cdef:
-        uint16_t num_pgdigits = <uint16_t>hton.unpack_int16(buf.read(2))
-        int16_t weight = hton.unpack_int16(buf.read(2))
-        uint16_t sign = <uint16_t>hton.unpack_int16(buf.read(2))
-        uint16_t dscale = <uint16_t>hton.unpack_int16(buf.read(2))
+        uint16_t num_pgdigits = <uint16_t>hton.unpack_int16(frb_read(buf, 2))
+        int16_t weight = hton.unpack_int16(frb_read(buf, 2))
+        uint16_t sign = <uint16_t>hton.unpack_int16(frb_read(buf, 2))
+        uint16_t dscale = <uint16_t>hton.unpack_int16(frb_read(buf, 2))
         int16_t pgdigit0
         ssize_t i
         int16_t pgdigit
@@ -161,7 +161,7 @@ cdef numeric_decode_binary(CodecContext settings, FastReadBuffer buf):
         # Zero
         return _Dec('0e-' + str(dscale))
 
-    pgdigit0 = hton.unpack_int16(buf.read(2))
+    pgdigit0 = hton.unpack_int16(frb_read(buf, 2))
     if weight >= 0:
         if pgdigit0 < 10:
             front_padding = 3
@@ -211,7 +211,7 @@ cdef numeric_decode_binary(CodecContext settings, FastReadBuffer buf):
             bufptr = _unpack_digit(bufptr, pgdigit0)
 
         for i in range(1, num_pgdigits):
-            pgdigit = hton.unpack_int16(buf.read(2))
+            pgdigit = hton.unpack_int16(frb_read(buf, 2))
             bufptr = _unpack_digit(bufptr, pgdigit)
 
         if dscale:

codecs/text.pyx

@@ -43,6 +43,6 @@ cdef inline decode_pg_string(CodecContext settings, const char* data,
         return settings.get_text_codec().decode(bytes)
 
 
-cdef text_decode(CodecContext settings, FastReadBuffer buf):
+cdef text_decode(CodecContext settings, FRBuffer *buf):
     cdef ssize_t buf_len = buf.len
-    return decode_pg_string(settings, buf.read_all(), buf_len)
+    return decode_pg_string(settings, frb_read_all(buf), buf_len)

codecs/tid.pyx

@@ -40,12 +40,12 @@ cdef tid_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_int16(<int16_t>offset)
 
 
-cdef tid_decode(CodecContext settings, FastReadBuffer buf):
+cdef tid_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         uint32_t block
         uint16_t offset
 
-    block = <uint32_t>hton.unpack_int32(buf.read(4))
-    offset = <uint16_t>hton.unpack_int16(buf.read(2))
+    block = <uint32_t>hton.unpack_int32(frb_read(buf, 4))
+    offset = <uint16_t>hton.unpack_int16(frb_read(buf, 2))
 
     return (block, offset)

codecs/txid.pyx

@@ -39,7 +39,7 @@ cdef txid_snapshot_encode(CodecContext settings, WriteBuffer buf, obj):
     buf.write_buffer(xip_buf)
 
 
-cdef txid_snapshot_decode(CodecContext settings, FastReadBuffer buf):
+cdef txid_snapshot_decode(CodecContext settings, FRBuffer *buf):
     cdef:
         int32_t nxip
         int64_t xmin
@@ -48,13 +48,13 @@ cdef txid_snapshot_decode(CodecContext settings, FastReadBuffer buf):
         int32_t i
         object xip
 
-    nxip = hton.unpack_int32(buf.read(4))
-    xmin = hton.unpack_int64(buf.read(8))
-    xmax = hton.unpack_int64(buf.read(8))
+    nxip = hton.unpack_int32(frb_read(buf, 4))
+    xmin = hton.unpack_int64(frb_read(buf, 8))
+    xmax = hton.unpack_int64(frb_read(buf, 8))
 
     xip_tup = cpython.PyTuple_New(nxip)
     for i in range(nxip):
-        xip = cpython.PyLong_FromLongLong(hton.unpack_int64(buf.read(8)))
+        xip = cpython.PyLong_FromLongLong(hton.unpack_int64(frb_read(buf, 8)))
         cpython.Py_INCREF(xip)
         cpython.PyTuple_SET_ITEM(xip_tup, i, xip)
 

codecs/uuid.pyx

@@ -18,5 +18,5 @@ cdef uuid_encode(CodecContext settings, WriteBuffer wbuf, obj):
     bytea_encode(settings, wbuf, obj.bytes)
 
 
-cdef uuid_decode(CodecContext settings, FastReadBuffer buf):
+cdef uuid_decode(CodecContext settings, FRBuffer *buf):
     return _UUID(bytes=bytea_decode(settings, buf))

frb.pxd

@@ -0,0 +1,49 @@
+# Copyright (C) 2016-present the asyncpg authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of asyncpg and is released under
+# the Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0
+
+
+cdef:
+
+    struct FRBuffer:
+        const char* buf
+        ssize_t len
+
+    inline ssize_t frb_get_len(FRBuffer *frb):
+        return frb.len
+
+    inline void frb_set_len(FRBuffer *frb, ssize_t new_len):
+        frb.len = new_len
+
+    inline void frb_init(FRBuffer *frb, const char *buf, ssize_t len):
+        frb.buf = buf
+        frb.len = len
+
+    inline const char* frb_read(FRBuffer *frb, ssize_t n) except NULL:
+        cdef const char *result
+
+        if n > frb.len:
+            frb_check(frb, n)
+
+        result = frb.buf
+        frb.buf += n
+        frb.len -= n
+
+        return result
+
+    inline const char* frb_read_all(FRBuffer *frb):
+        cdef const char *result
+        result = frb.buf
+        frb.buf += frb.len
+        frb.len = 0
+        return result
+
+    inline FRBuffer *frb_slice_from(FRBuffer *frb,
+                                    FRBuffer* source, ssize_t len):
+        frb.buf = frb_read(source, len)
+        frb.len = len
+        return frb
+
+    object frb_check(FRBuffer *frb, ssize_t n)

frb.pyx

@@ -0,0 +1,12 @@
+# Copyright (C) 2016-present the asyncpg authors and contributors
+# <see AUTHORS file>
+#
+# This module is part of asyncpg and is released under
+# the Apache 2.0 License: http://www.apache.org/licenses/LICENSE-2.0
+
+
+cdef object frb_check(FRBuffer *frb, ssize_t n):
+    if n > frb.len:
+        raise AssertionError(
+            f'insufficient data in buffer: requested {n} '
+            f'remaining {frb.len}')

pgproto.pxd

@@ -12,6 +12,7 @@ from libc.stdint cimport int16_t, int32_t, uint16_t, uint32_t, int64_t, uint64_t
 
 
 include "./consts.pxi"
+include "./frb.pxd"
 include "./buffer.pxd"
 
 

pgproto.pyx

@@ -17,10 +17,12 @@ from libc.stdint cimport int8_t, uint8_t, int16_t, uint16_t, \
 
 
 from . cimport hton
+
 from .debug cimport PG_DEBUG
 
 
 include "./consts.pxi"
+include "./frb.pyx"
 include "./buffer.pyx"
 
 include "./codecs/context.pyx"