package git

  1. Overview
  2. Docs
package git
Legend:
Page
Library
Module
Module type
Parameter
Class
Class type
Source

Module Pkt_line.DecoderSource

Module for decoding Git pkt lines, as specified at https://github.com/git/git/blob/master/Documentation/technical/protocol-common.txt

We define a "packet line" (aka a "packet") as

| 4 bytes || (enc-pkt-len)-4 | enc-pkt-len pkt-content |------- pkt-len ------|

Example: "0009done\n" where enc-pkt-len = 4 and pkt-content = "done" given we usually trim LF ("\n").

"Encoded" packet length, enc-pkt-len, is the first 4 bytes in the packet that encode the length of the packet in hex. It can have specific values of 0, 1, 2 to encode flush, delimiter, and message (response end) packets respectively. Otherwise, it should be >= 4, i.e., 4 length bytes + the length of the packet content.

In the docs, we define min_pkt_len = 4 as in specs.

Sourcetype decoder = {
  1. buffer : bytes;
  2. mutable pos : int;
  3. mutable max : int;
}
Sourceval io_buffer_size : int
Sourceval create : unit -> decoder
Sourceval of_string : string -> decoder
Sourceval end_of_input : decoder -> int
Sourcetype error = [
  1. | `End_of_input
  2. | `Expected_char of char
  3. | `Unexpected_char of char
  4. | `Expected_string of string
  5. | `Expected_eol
  6. | `Expected_eol_or_space
  7. | `Unexpected_end_of_input
  8. | `No_enough_space
  9. | `Assert_predicate of char -> bool
  10. | `Invalid_pkt_line of string
]
Sourceval pp_error : error Fmt.t
Sourcetype 'err info = {
  1. error : 'err;
  2. buffer : bytes;
  3. committed : int;
}
Sourceexception Leave of error info
Sourcetype ('v, 'err) state =
  1. | Done of 'v
  2. | Read of {
    1. buffer : bytes;
    2. off : int;
    3. len : int;
    4. continue : int -> ('v, 'err) state;
    5. eof : unit -> ('v, 'err) state;
    }
  3. | Error of 'err info
Sourceval return : 'v -> decoder -> ('v, 'err) state
Sourceval bind : ('a, 'b) state -> f:('a -> ('c, 'b) state) -> ('c, 'b) state
Sourceval (>>=) : ('a, 'b) state -> ('a -> ('c, 'b) state) -> ('c, 'b) state
Sourceval leave_with : decoder -> error -> 'never

leave_with d error raises Leave { error; buffer = d.buffer; committed = d.pos }

Sourceval safe : (decoder -> ('v, [> error ] as 'err) state) -> decoder -> ('v, 'err) state

safe k decoder wraps a call k decoder in a try-with block; if exception Leave err is raised, the function returns Error of err

Sourceval fail : decoder -> [> error ] as 'err -> ('v, 'err) state
Sourceval peek_char : decoder -> char option
Sourceval string : string -> decoder -> unit
Sourceval junk_char : decoder -> unit
Sourceval while1 : (char -> bool) -> decoder -> bytes * int * int
  • returns

    decoder.buffer, updated decoder.pos, # of bytes read

Sourceval at_least_one_pkt : decoder -> bool

returns true if decoder.max - decoder.pos is >= min_pkt_len and >= pkt_len, where pkt_len is the length of a pkt line starting at decoder.pos.

Sourceval at_least_one_line : decoder -> bool
Sourceval prompt : ?strict:bool -> (decoder -> ('v, [> error ] as 'err) state) -> decoder -> ('v, 'err) state
Sourceval peek_while_eol : decoder -> bytes * int * int
Sourceval peek_while_eol_or_space : decoder -> bytes * int * int
Sourceval peek_pkt : decoder -> bytes * int * int
Sourceval junk_pkt : decoder -> unit

increase decoder.pos by max min_pkt_len pkt_len, where pkt_len is the length of the pkt line starting at the current value of decoder.pos (before increasing) and min_pkt_len = 4.

  • raises Invalid_argument

    if there aren't 4 bytes representing the length

Sourceval prompt_pkt : ?strict:bool -> (decoder -> ('a, [> error ] as 'b) state) -> decoder -> ('a, 'b) state

/

Sourceval pkt_len_unsafe : decoder -> int
OCaml

Innovation. Community. Security.

GitHub Discord Twitter Peertube RSS
About
Changelog Releases Industrial Users Academic Users Why OCaml
Ecosystem
Packages Community Events OCaml Planet Jobs
Resources
Install OCaml Get Started Platform Tools Language Manual Standard Library API Books Exercises Papers OCaml Playground Logo
Policies
Carbon Footprint Governance Privacy Code of Conduct