Module Bi_inbuf
type t = {
i_s : string; (* This is the buffer string.
It can be accessed for reading but should normally only
be written to or replaced only by the
i_refill function. *)i_pos : int; (* This is the current position in the input buffer.
All data before that may be erased at anytime. *)
i_len : int; (* This is the position of the first byte of invalid input data.
Data starting at
i_pos and ending at i_len-1 is considered
valid input data that is available to the user.
Beware that calls to try_preread, read and other read functions
may move data around and therefore modify the values
of i_pos and i_len in order to keep pointing to the
correct data segment. *)i_offs : int; (* Length of data read and discarded from the buffer.
This indicates the position in the input stream of
the first byte of the buffer.
The current position in the input stream is
i_offs + i_pos.
The total length of input stream data put into the buffer is
i_offs + i_len. *)i_max_len : int; (* This is the length of
i_s. *)i_refill : t -> int -> unit; (* Function called when not enough data is available in the buffer.
The int argument is the total number of bytes that must be
available starting at position
}
i_pos when the function returns.
This function typically does nothing if all input data already has been
placed into the buffer.
The i_pos and i_len fields can be modified the i_refill function,
as long as the available data that was starting from i_pos
still starts from the new value of i_pos.
All the other fields can be modified as well. *)
exception End_of_input
Exception raised by all the functions of this module
when it is not possible to return a valid result
because there is not enough data to read from the buffer.
val try_preread : t -> int -> int
try_preread ib n make at least n bytes available for reading
in ib.i_s, unless the end of the input is reached.
The result indicates how many bytes were made available. If smaller than
n, the result indicates that the end of the input was reached.
ib.i_pos is set to point to the first available byte.
val read : t -> int -> int
read ib n makes at least n bytes available for reading or raises
the End_of_input exception.
The result is the position of the first available byte.
ib.i_pos is moved to point to the next position after the n bytes.
Raises
End_of_input if there is less than n bytes
before the end of input.
val read_char : t -> char
Read just one byte.
Raises
End_of_input if the end of input has already been reached.
val peek : t -> char
Return the next byte without moving forward.
Raises
End_of_input if the end of input has already been reached.
val from_string : ?pos:int -> ?shrlen:int -> string -> t
Create an input buffer from a string.
pos position to start from. Default: 0.
shrlen initial length of the table used to store shared values.
val from_channel : ?len:int -> ?shrlen:int -> Pervasives.in_channel -> t
Create an input buffer from an in_channel.
Such a buffer is not extensible and
read requests may not exceed len.
len buffer length.
shrlen initial length of the table used to store shared values.