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	diff --git a/lib/gen_magic/helpers.ex b/lib/gen_magic/helpers.ex
	index 183fe31..13ab3de 100644
	--- a/lib/gen_magic/helpers.ex
	+++ b/lib/gen_magic/helpers.ex
	@@ -1,28 +1,30 @@
	defmodule GenMagic.Helpers do
	@moduledoc """
	Contains convenience functions for one-off use.
	"""

	alias GenMagic.Result
	alias GenMagic.Server
	- @spec perform_once(Path.t(), [Server.option()]) :: {:ok, Result.t()} \| {:error, term()}
	+
	+ @spec perform_once(Path.t() \| {:bytes, binary}, [Server.option()]) ::
	+ {:ok, Result.t()} \| {:error, term()}

	@doc """
	Runs a one-shot process without supervision.

	Useful in tests, but not recommended for actual applications.

	## Example

	iex(1)> {:ok, result} = GenMagic.Helpers.perform_once(".")
	iex(2)> result
	%GenMagic.Result{content: "directory", encoding: "binary", mime_type: "inode/directory"}
	"""
	def perform_once(path, options \\ []) do
	with {:ok, pid} <- Server.start_link(options),
	{:ok, result} <- Server.perform(pid, path),
	:ok <- Server.stop(pid) do
	{:ok, result}
	end
	end
	end
	diff --git a/lib/gen_magic/server.ex b/lib/gen_magic/server.ex
	index 09cdd41..f057dda 100644
	--- a/lib/gen_magic/server.ex
	+++ b/lib/gen_magic/server.ex
	@@ -1,302 +1,301 @@
	defmodule GenMagic.Server do
	@moduledoc """
	Provides access to the underlying libmagic client, which performs file introspection.

	The Server needs to be supervised, since it will terminate if it receives any unexpected error.
	"""

	@behaviour :gen_statem
	alias GenMagic.Result
	alias GenMagic.Server.Data
	alias GenMagic.Server.Status
	import Kernel, except: [send: 2]

	@typedoc """
	Represents the reference to the underlying server, as returned by `:gen_statem`.
	"""
	@type t :: :gen_statem.server_ref()

	@typedoc """
	Represents values accepted as startup options, which can be passed to `start_link/1`.

	- `:name`: If present, this will be the registered name for the underlying process.
	Note that `:gen_statem` requires `{:local, name}`, but given widespread GenServer convention,
	atoms are accepted and will be converted to `{:local, name}`.

	- `:startup_timeout`: Specifies how long the Server waits for the C program to initialise.
	However, if the underlying C program exits, then the process exits immediately.

	Can be set to `:infinity`.

	- `:process_timeout`: Specifies how long the Server waits for each request to complete.

	Can be set to `:infinity`.

	Please note that, if you have chosen a custom timeout value, you should also pass it when
	using `GenMagic.Server.perform/3`.

	- `:recycle_threshold`: Specifies the number of requests processed before the underlying C
	program is recycled.

	Can be set to `:infinity` if you do not wish for the program to be recycled.

	- `:database_patterns`: Specifies what magic databases to load; you can specify a list of either
	Path Patterns (see `Path.wildcard/2`) or `:default` to instruct the C program to load the
	appropriate databases.

	For example, if you have had to add custom magics, then you can set this value to:

	[:default, "path/to/my/magic"]
	"""
	@type option ::
	{:name, atom() \| :gen_statem.server_name()}
	\| {:startup_timeout, timeout()}
	\| {:process_timeout, timeout()}
	\| {:recycle_threshold, non_neg_integer() \| :infinity}
	\| {:database_patterns, nonempty_list(:default \| Path.t())}

	@typedoc """
	Current state of the Server:

	- `:pending`: This is the initial state; the Server will attempt to start the underlying Port
	and the libmagic client, then automatically transition to either Available or Crashed.

	- `:available`: This is the default state. In this state the Server is able to accept requests
	and they will be replied in the same order.

	- `:processing`: This is the state the Server will be in if it is processing requests. In this
	state, further requests can still be lodged and they will be processed when the Server is
	available again.

	For proper concurrency, use a process pool like Poolboy, Sbroker, etc.

	- `:recycling`: This is the state the Server will be in, if its underlying C program needs to be
	recycled. This state is triggered whenever the cycle count reaches the defined value as per
	`:recycle_threshold`.

	In this state, the Server is able to accept requests, but they will not be processed until the
	underlying C server program has been started again.
	"""
	@type state :: :starting \| :processing \| :available \| :recycling

	@spec child_spec([option()]) :: Supervisor.child_spec()
	@spec start_link([option()]) :: :gen_statem.start_ret()
	- @spec perform(t(), Path.t(), timeout()) :: {:ok, Result.t()} \| {:error, term() \| String.t()}
	+ @spec perform(t(), Path.t() \| {:bytes, binary()}, timeout()) ::
	+ {:ok, Result.t()} \| {:error, term() \| String.t()}
	@spec status(t(), timeout()) :: {:ok, Status.t()} \| {:error, term()}
	@spec stop(t(), term(), timeout()) :: :ok

	@doc """
	Returns the default Child Specification for this Server for use in Supervisors.

	You can override this with `Supervisor.child_spec/2` as required.
	"""
	def child_spec(options) do
	%{
	id: __MODULE__,
	start: {__MODULE__, :start_link, [options]},
	type: :worker,
	restart: :permanent,
	shutdown: 500
	}
	end

	@doc """
	Starts a new Server.

	See `t:option/0` for further details.
	"""
	def start_link(options) do
	{name, options} = Keyword.pop(options, :name)

	case name do
	nil -> :gen_statem.start_link(__MODULE__, options, [])
	name when is_atom(name) -> :gen_statem.start_link({:local, name}, __MODULE__, options, [])
	{:global, _} -> :gen_statem.start_link(name, __MODULE__, options, [])
	{:via, _, _} -> :gen_statem.start_link(name, __MODULE__, options, [])
	{:local, _} -> :gen_statem.start_link(name, __MODULE__, options, [])
	end
	end

	@doc """
	Determines the type of the file provided.
	"""
	def perform(server_ref, path, timeout \\ 5000) do
	case :gen_statem.call(server_ref, {:perform, path}, timeout) do
	{:ok, %Result{} = result} -> {:ok, result}
	{:error, reason} -> {:error, reason}
	end
	end

	@doc """
	Returns status of the Server.
	"""
	def status(server_ref, timeout \\ 5000) do
	:gen_statem.call(server_ref, :status, timeout)
	end

	@doc """
	Stops the Server with reason `:normal` and timeout `:infinity`.
	"""
	def stop(server_ref) do
	:gen_statem.stop(server_ref)
	end

	@doc """
	Stops the Server with the specified reason and timeout.
	"""
	def stop(server_ref, reason, timeout) do
	:gen_statem.stop(server_ref, reason, timeout)
	end

	@impl :gen_statem
	def init(options) do
	import GenMagic.Config

	data = %Data{
	port_name: get_port_name(),
	port_options: get_port_options(options),
	startup_timeout: get_startup_timeout(options),
	process_timeout: get_process_timeout(options),
	recycle_threshold: get_recycle_threshold(options)
	}

	{:ok, :starting, data}
	end

	@impl :gen_statem
	def callback_mode do
	[:state_functions, :state_enter]
	end

	@doc false
	def starting(:enter, _, %{request: nil, port: nil} = data) do
	port = Port.open(data.port_name, data.port_options)
	{:keep_state, %{data \| port: port}, data.startup_timeout}
	end

	@doc false
	def starting({:call, from}, :status, data) do
	handle_status_call(from, :starting, data)
	end

	@doc false
	def starting({:call, _from}, {:perform, _path}, _data) do
	{:keep_state_and_data, :postpone}
	end

	@doc false
	- def starting(:info, {port, {:data, binary}}, %{port: port} = data) do
	- case :erlang.binary_to_term(binary) do
	- :ready ->
	- {:next_state, :available, data}
	+ def starting(:info, {port, {:data, ready}}, %{port: port} = data) do
	+ case :erlang.binary_to_term(ready) do
	+ :ready -> {:next_state, :available, data}
	end
	end

	def starting(:info, {port, {:exit_status, code}}, %{port: port} = data) do
	error =
	case code do
	1 -> :no_database
	2 -> :no_argument
	3 -> :missing_database
	+ code -> {:unexpected_error, code}
	end

	{:stop, {:error, error}, data}
	end

	@doc false
	def available(:enter, _old_state, %{request: nil}) do
	:keep_state_and_data
	end

	@doc false
	def available({:call, from}, {:perform, path}, data) do
	data = %{data \| cycles: data.cycles + 1, request: {path, from, :erlang.now()}}

	arg =
	case path do
	path when is_binary(path) -> {:file, path}
	{:bytes, bytes} -> {:bytes, bytes}
	end

	send(data.port, arg)
	{:next_state, :processing, data}
	end

	@doc false
	def available({:call, from}, :status, data) do
	handle_status_call(from, :available, data)
	end

	@doc false
	def processing(:enter, _old_state, %{request: {_path, _from, _time}} = data) do
	{:keep_state_and_data, data.process_timeout}
	end

	@doc false
	def processing({:call, _from}, {:perform, _path}, _data) do
	{:keep_state_and_data, :postpone}
	end

	@doc false
	def processing({:call, from}, :status, data) do
	handle_status_call(from, :processing, data)
	end

	@doc false
	- def processing(:info, {port, {:data, response}}, %{port: port} = data) do
	- {_, from, _} = data.request
	- data = %{data \| request: nil}
	+ def processing(:info, {port, {:data, response}}, %{port: port, request: {_, from, _}} = data) do
	response = {:reply, from, handle_response(response)}
	next_state = (data.cycles >= data.recycle_threshold && :recycling) \|\| :available
	- {:next_state, next_state, data, [response, :hibernate]}
	+ {:next_state, next_state, %{data \| request: nil}, [response, :hibernate]}
	end

	@doc false
	def recycling(:enter, _, %{request: nil, port: port} = data) when is_port(port) do
	send(data.port, {:stop, :recycle})
	{:keep_state_and_data, data.startup_timeout}
	end

	@doc false
	def recycling({:call, _from}, {:perform, _path}, _data) do
	{:keep_state_and_data, :postpone}
	end

	@doc false
	def recycling({:call, from}, :status, data) do
	handle_status_call(from, :recycling, data)
	end

	@doc false
	def recycling(:info, {port, {:exit_status, 0}}, %{port: port} = data) do
	{:next_state, :starting, %{data \| port: nil, cycles: 0}}
	end

	defp send(port, command) do
	Kernel.send(port, {self(), {:command, :erlang.term_to_binary(command)}})
	end

	@errnos %{
	2 => :enoent,
	13 => :eaccess,
	- 21 => :eisdir,
	20 => :enotdir,
	12 => :enomem,
	24 => :emfile,
	- 36 => :enametoolong,
	+ 36 => :enametoolong
	}
	@errno Map.keys(@errnos)

	defp handle_response(data) do
	case :erlang.binary_to_term(data) do
	{:ok, {mime_type, encoding, content}} -> {:ok, Result.build(mime_type, encoding, content)}
	{:error, {errno, _}} when errno in @errno -> {:error, @errnos[errno]}
	{:error, {errno, string}} -> {:error, "#{errno}: #{string}"}
	+ {:error, _} = error -> error
	end
	end

	defp handle_status_call(from, state, data) do
	response = {:ok, %__MODULE__.Status{state: state, cycles: data.cycles}}
	{:keep_state_and_data, {:reply, from, response}}
	end
	end
	diff --git a/src/apprentice.c b/src/apprentice.c
	index 33c42b5..10c09b9 100644
	--- a/src/apprentice.c
	+++ b/src/apprentice.c
	@@ -1,406 +1,444 @@
	//
	// The Sorcerer’s Apprentice
	//
	// To use this program, compile it with dynamically linked libmagic, as mirrored
	-// at https://github.com/threatstack/libmagic. You may install it with apt-get,
	+// at https://github.com/file/file. You may install it with apt-get,
	// yum or brew. Refer to the Makefile for further reference.
	//
	// This program is designed to run interactively as a backend daemon to the
	// GenMagic library, and follows the command line pattern:
	//
	// $ apprentice --database-file <file> --database-default
	//
	// Where each argument either refers to a compiled or uncompiled magic database,
	// or the default database. They will be loaded in the sequence that they were
	-// specified. Note that you must specify at least one database. Erlang Term
	+// specified. Note that you must specify at least one database.
	//
	-// -- main: send atom ready
	-// enter loop
	+// Communication is done over STDIN/STDOUT as binary packets of 2 bytes length
	+// plus X bytes payload, where the payload is an erlang term encoded with
	+// :erlang.term_to_binary/1 and decoded with :erlang.binary_to_term/1.
	//
	-// -- while
	-// get {:file, path} -> process_file -> ok \| error
	-// {:bytes, path} -> process_bytes -> ok \| error
	-// ok: {:ok, {type, encoding, name}}
	-// error: {:error, :badarg} \| {:error, {errno, String.t()}}
	-// {:stop, _} -> exit(ERROR_OK) -> exit 0
	+// Once the program is ready, it sends the `:ready` atom. The startup can fail
	+// for multiples reasons, and the program will exit accordingly:
	+// - 1: No database
	+// - 2: Missing/Bad argument
	+// - 3: Missing database
	//
	+// Commands are sent to the program STDIN as an erlang term of `{Operation,
	+// Argument}`, and response of `{:ok \| :error, Response}`.
	+//
	+// Invalid packets will cause the program to exit (exit code 4). This will
	+// happen if your Erlang Term format doesn't match the version the program has
	+// been compiled with, or if you send a command too huge.
	+//
	+// The program may exit with error codes 5 or 255 if something went wrong (such
	+// as error allocating terms, or if stdin is lost).
	+//
	+// Commands:
	+// {:file, path :: String.t()} :: {:ok, {type, encoding, name}} \| {:error,
	+// :badarg} \| {:error, {errno :: integer(), String.t()}}
	+// {:bytes, binary()} :: same as :file
	+// {:stop, reason :: atom()} :: exit 0
	+
	#include <ei.h>
	#include <errno.h>
	#include <getopt.h>
	#include <libgen.h>
	#include <magic.h>
	#include <stdarg.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <sys/stat.h>
	#include <sys/types.h>
	#include <unistd.h>
	-#define USAGE "[--database-file <path/to/magic.mgc> \| --database-default, ...]"
	-#define DELIMITER "\t"

	#define ERROR_OK 0
	#define ERROR_NO_DATABASE 1
	#define ERROR_NO_ARGUMENT 2
	#define ERROR_MISSING_DATABASE 3
	#define ERROR_BAD_TERM 4
	#define ERROR_EI 5

	-#define ANSI_INFO "\x1b[37m" // gray
	-#define ANSI_OK "\x1b[32m" // green
	-#define ANSI_ERROR "\x1b[31m" // red
	-#define ANSI_IGNORE "\x1b[90m" // red
	-#define ANSI_RESET "\x1b[0m"
	+// We use a bigger than possible valid command length (around 4111 bytes) to
	+// allow more precise errors when using too long paths.
	+#define COMMAND_LEN 8000
	+#define COMMAND_BUFFER_SIZE COMMAND_LEN + 1

	#define MAGIC_FLAGS_COMMON (MAGIC_CHECK \| MAGIC_ERROR)
	magic_t magic_setup(int flags);

	typedef char byte;

	void setup_environment();
	void setup_options(int argc, char **argv);
	void setup_options_file(char *optarg);
	void setup_options_default();
	void setup_system();
	-int process_command(byte *buf);
	-void process_line(char *line);
	+int process_command(uint16_t len, byte *buf);
	void process_file(char path, ei_x_buff result);
	void process_bytes(char bytes, int size, ei_x_buff result);
	size_t read_cmd(byte *buf);
	size_t write_cmd(byte *buf, size_t len);
	void error(ei_x_buff result, const char error);
	void handle_magic_error(magic_t handle, int errn, ei_x_buff *result);
	+void fdseek(uint16_t count);

	struct magic_file {
	struct magic_file *prev;
	struct magic_file *next;
	char *path;
	};

	static struct magic_file *magic_database;
	static magic_t magic_mime_type; // MAGIC_MIME_TYPE
	static magic_t magic_mime_encoding; // MAGIC_MIME_ENCODING
	static magic_t magic_type_name; // MAGIC_NONE

	int main(int argc, char **argv) {
	ei_init();
	setup_environment();
	setup_options(argc, argv);
	setup_system();

	ei_x_buff ok_buf;
	if (ei_x_new_with_version(&ok_buf) \|\| ei_x_encode_atom(&ok_buf, "ready"))
	exit(ERROR_EI);
	write_cmd(ok_buf.buff, ok_buf.index);
	if (ei_x_free(&ok_buf) != 0)
	exit(ERROR_EI);

	- byte buf[4112];
	- while (read_cmd(buf) > 0) {
	- process_command(buf);
	+ byte buf[COMMAND_BUFFER_SIZE];
	+ uint16_t len;
	+ while ((len = read_cmd(buf)) > 0) {
	+ process_command(len, buf);
	}

	return 255;
	}

	-int process_command(byte *buf) {
	+int process_command(uint16_t len, byte *buf) {
	ei_x_buff result;
	char atom[128];
	int index, version, arity, termtype, termsize;
	index = 0;

	- if (ei_decode_version(buf, &index, &version) != 0) {
	- exit(ERROR_BAD_TERM);
	- }
	-
	// Initialize result
	if (ei_x_new_with_version(&result) \|\| ei_x_encode_tuple_header(&result, 2)) {
	exit(ERROR_EI);
	}

	+ if (len >= COMMAND_LEN) {
	+ error(&result, "badarg");
	+ return 1;
	+ }
	+
	+ if (ei_decode_version(buf, &index, &version) != 0) {
	+ exit(ERROR_BAD_TERM);
	+ }
	+
	if (ei_decode_tuple_header(buf, &index, &arity) != 0) {
	error(&result, "badarg");
	return 1;
	}

	if (arity != 2) {
	error(&result, "badarg");
	return 1;
	}

	if (ei_decode_atom(buf, &index, atom) != 0) {
	error(&result, "badarg");
	return 1;
	}

	if (strlen(atom) == 4 && strncmp(atom, "file", 4) == 0) {
	char path[4097];
	ei_get_type(buf, &index, &termtype, &termsize);

	- if (termtype == ERL_BINARY_EXT && termsize < 4096) {
	- long bin_length;
	- ei_decode_binary(buf, &index, path, &bin_length);
	- path[termsize] = '\0';
	- process_file(path, &result);
	+ if (termtype == ERL_BINARY_EXT) {
	+ if (termsize < 4096) {
	+ long bin_length;
	+ ei_decode_binary(buf, &index, path, &bin_length);
	+ path[termsize] = '\0';
	+ process_file(path, &result);
	+ } else {
	+ error(&result, "enametoolong");
	+ return 1;
	+ }
	} else {
	error(&result, "badarg");
	return 1;
	}
	} else if (strlen(atom) == 5 && strncmp(atom, "bytes", 5) == 0) {
	int termtype;
	int termsize;
	char bytes[51];
	ei_get_type(buf, &index, &termtype, &termsize);

	if (termtype == ERL_BINARY_EXT && termsize < 50) {
	long bin_length;
	ei_decode_binary(buf, &index, bytes, &bin_length);
	bytes[termsize] = '\0';
	process_bytes(bytes, termsize, &result);
	} else {
	error(&result, "badarg");
	return 1;
	}
	} else if (strlen(atom) == 4 && strncmp(atom, "stop", 4) == 0) {
	exit(ERROR_OK);
	} else {
	error(&result, "badarg");
	return 1;
	}

	write_cmd(result.buff, result.index);

	if (ei_x_free(&result) != 0) {
	exit(ERROR_EI);
	}
	return 0;
	}

	void setup_environment() { opterr = 0; }

	void setup_options(int argc, char **argv) {
	const char *option_string = "f:";
	static struct option long_options[] = {
	{"database-file", required_argument, 0, 'f'},
	{"database-default", no_argument, 0, 'd'},
	{0, 0, 0, 0}};

	int option_character;
	while (1) {
	int option_index = 0;
	option_character =
	getopt_long(argc, argv, option_string, long_options, &option_index);
	if (-1 == option_character) {
	break;
	}
	switch (option_character) {
	case 'f': {
	setup_options_file(optarg);
	break;
	}
	case 'd': {
	setup_options_default();
	break;
	}
	case '?':
	default: {
	exit(ERROR_NO_ARGUMENT);
	break;
	}
	}
	}
	}

	void setup_options_file(char *optarg) {
	if (0 != access(optarg, R_OK)) {
	exit(ERROR_MISSING_DATABASE);
	}

	struct magic_file *next = malloc(sizeof(struct magic_file));
	size_t path_length = strlen(optarg) + 1;
	char *path = malloc(path_length);
	memcpy(path, optarg, path_length);
	next->path = path;
	next->prev = magic_database;
	if (magic_database) {
	magic_database->next = next;
	}
	magic_database = next;
	}

	void setup_options_default() {

	struct magic_file *next = malloc(sizeof(struct magic_file));
	next->path = NULL;
	next->prev = magic_database;
	if (magic_database) {
	magic_database->next = next;
	}
	magic_database = next;
	}

	void setup_system() {
	magic_mime_encoding = magic_setup(MAGIC_FLAGS_COMMON \| MAGIC_MIME_ENCODING);
	magic_mime_type = magic_setup(MAGIC_FLAGS_COMMON \| MAGIC_MIME_TYPE);
	magic_type_name = magic_setup(MAGIC_FLAGS_COMMON \| MAGIC_NONE);
	}

	magic_t magic_setup(int flags) {

	magic_t magic = magic_open(flags);
	struct magic_file *current_database = magic_database;
	if (!current_database) {
	exit(ERROR_NO_DATABASE);
	}

	while (current_database->prev) {
	current_database = current_database->prev;
	}
	while (current_database) {
	magic_load(magic, current_database->path);
	current_database = current_database->next;
	}
	return magic;
	}

	void process_bytes(char path, int size, ei_x_buff result) {
	const char *mime_type_result = magic_buffer(magic_mime_type, path, size);
	const int mime_type_errno = magic_errno(magic_mime_type);

	if (mime_type_errno > 0) {
	handle_magic_error(magic_mime_type, mime_type_errno, result);
	return;
	}

	const char *mime_encoding_result =
	magic_buffer(magic_mime_encoding, path, size);
	int mime_encoding_errno = magic_errno(magic_mime_encoding);

	if (mime_encoding_errno > 0) {
	handle_magic_error(magic_mime_encoding, mime_encoding_errno, result);
	return;
	}

	const char *type_name_result = magic_buffer(magic_type_name, path, size);
	int type_name_errno = magic_errno(magic_type_name);

	if (type_name_errno > 0) {
	handle_magic_error(magic_type_name, type_name_errno, result);
	return;
	}

	ei_x_encode_atom(result, "ok");
	ei_x_encode_tuple_header(result, 3);
	ei_x_encode_binary(result, mime_type_result, strlen(mime_type_result));
	ei_x_encode_binary(result, mime_encoding_result,
	strlen(mime_encoding_result));
	ei_x_encode_binary(result, type_name_result, strlen(type_name_result));
	return;
	}

	void handle_magic_error(magic_t handle, int errn, ei_x_buff *result) {
	const char *error = magic_error(handle);
	ei_x_encode_atom(result, "error");
	ei_x_encode_tuple_header(result, 2);
	long errlon = (long)errn;
	ei_x_encode_long(result, errlon);
	ei_x_encode_binary(result, error, strlen(error));
	return;
	}

	void process_file(char path, ei_x_buff result) {
	const char *mime_type_result = magic_file(magic_mime_type, path);
	const int mime_type_errno = magic_errno(magic_mime_type);

	if (mime_type_errno > 0) {
	handle_magic_error(magic_mime_type, mime_type_errno, result);
	return;
	}

	const char *mime_encoding_result = magic_file(magic_mime_encoding, path);
	int mime_encoding_errno = magic_errno(magic_mime_encoding);

	if (mime_encoding_errno > 0) {
	handle_magic_error(magic_mime_encoding, mime_encoding_errno, result);
	return;
	}

	const char *type_name_result = magic_file(magic_type_name, path);
	int type_name_errno = magic_errno(magic_type_name);

	if (type_name_errno > 0) {
	handle_magic_error(magic_type_name, type_name_errno, result);
	return;
	}

	ei_x_encode_atom(result, "ok");
	ei_x_encode_tuple_header(result, 3);
	ei_x_encode_binary(result, mime_type_result, strlen(mime_type_result));
	ei_x_encode_binary(result, mime_encoding_result,
	strlen(mime_encoding_result));
	ei_x_encode_binary(result, type_name_result, strlen(type_name_result));
	return;
	}

	// Adapted from https://erlang.org/doc/tutorial/erl_interface.html
	// Changed `read_cmd`, the original one was buggy given some length (due to
	// endinaness).
	// TODO: Check if `write_cmd` exhibits the same issue.
	size_t read_exact(byte *buf, size_t len) {
	int i, got = 0;

	do {
	if ((i = read(0, buf + got, len - got)) <= 0) {
	return (i);
	}
	got += i;
	} while (got < len);

	return (len);
	}

	size_t write_exact(byte *buf, size_t len) {
	int i, wrote = 0;

	do {
	if ((i = write(1, buf + wrote, len - wrote)) <= 0)
	return (i);
	wrote += i;
	} while (wrote < len);

	return (len);
	}

	size_t read_cmd(byte *buf) {
	int i;
	if ((i = read(0, buf, sizeof(uint16_t))) <= 0) {
	return (i);
	}
	uint16_t len16 = (uint16_t )buf;
	len16 = ntohs(len16);
	- if (len16 > 4111) {
	- exit(ERROR_BAD_TERM);
	+
	+ // Buffer isn't large enough: just return possible len, without reading.
	+ // Up to the caller of verifying the size again and return an error.
	+ // buf left unchanged, stdin emptied of X bytes.
	+ if (len16 > COMMAND_LEN) {
	+ fdseek(len16);
	+ return len16;
	}
	+
	return read_exact(buf, len16);
	}

	size_t write_cmd(byte *buf, size_t len) {
	byte li;

	li = (len >> 8) & 0xff;
	write_exact(&li, 1);

	li = len & 0xff;
	write_exact(&li, 1);

	return write_exact(buf, len);
	}

	void error(ei_x_buff result, const char error) {
	ei_x_encode_atom(result, "error");
	ei_x_encode_atom(result, error);
	write_cmd(result->buff, result->index);

	if (ei_x_free(result) != 0)
	exit(ERROR_EI);
	}
	+
	+void fdseek(uint16_t count) {
	+ int i = 0;
	+ while (i < count) {
	+ getchar();
	+ i += 1;
	+ }
	+}
	diff --git a/test/gen_magic/apprentice_test.exs b/test/gen_magic/apprentice_test.exs
	index 06c9983..7c6b4b5 100644
	--- a/test/gen_magic/apprentice_test.exs
	+++ b/test/gen_magic/apprentice_test.exs
	@@ -1,112 +1,147 @@
	defmodule GenMagic.ApprenticeTest do
	use GenMagic.MagicCase

	+ @tmp_path "/tmp/testgenmagicx"
	+
	test "sends ready" do
	port = Port.open(GenMagic.Config.get_port_name(), GenMagic.Config.get_port_options([]))
	assert_ready(port)
	end

	test "stops" do
	port = Port.open(GenMagic.Config.get_port_name(), GenMagic.Config.get_port_options([]))
	assert_ready(port)
	send(port, {self(), {:command, :erlang.term_to_binary({:stop, :stop})}})
	assert_receive {^port, {:exit_status, 0}}
	end

	test "exits with no database" do
	opts = [:use_stdio, :binary, :exit_status, {:packet, 2}, {:args, []}]
	port = Port.open(GenMagic.Config.get_port_name(), opts)
	assert_receive {^port, {:exit_status, 1}}
	end

	test "exits with a non existent database" do
	opts = [
	{:args, ["--database-file", "/no/such/database"]},
	:use_stdio,
	:binary,
	:exit_status,
	{:packet, 2}
	]

	port = Port.open(GenMagic.Config.get_port_name(), opts)
	assert_receive {^port, {:exit_status, 3}}
	end

	describe "port" do
	setup do
	port = Port.open(GenMagic.Config.get_port_name(), GenMagic.Config.get_port_options([]))
	assert_ready(port)
	%{port: port}
	end

	test "exits with badly formatted erlang terms", %{port: port} do
	send(port, {self(), {:command, "i forgot to term_to_binary!!"}})
	assert_receive {^port, {:exit_status, 4}}
	end

	test "errors with wrong command", %{port: port} do
	send(port, {self(), {:command, :erlang.term_to_binary(:wrong)}})
	assert_receive {^port, {:data, data}}
	assert {:error, :badarg} = :erlang.binary_to_term(data)
	refute_receive _

	send(port, {self(), {:command, :erlang.term_to_binary({:file, 42})}})
	assert_receive {^port, {:data, data}}
	assert {:error, :badarg} = :erlang.binary_to_term(data)
	refute_receive _

	send(port, {self(), {:command, :erlang.term_to_binary("more wrong")}})
	assert_receive {^port, {:data, data}}
	assert {:error, :badarg} = :erlang.binary_to_term(data)
	refute_receive _

	send(port, {self(), {:command, :erlang.term_to_binary({"no", "no"})}})
	assert_receive {^port, {:data, data}}
	assert {:error, :badarg} = :erlang.binary_to_term(data)
	refute_receive _
	end

	test "file works", %{port: port} do
	send(port, {self(), {:command, :erlang.term_to_binary({:file, Path.expand("Makefile")})}})
	assert_receive {^port, {:data, data}}
	assert {:ok, _} = :erlang.binary_to_term(data)
	end

	test "bytes works", %{port: port} do
	send(port, {self(), {:command, :erlang.term_to_binary({:bytes, "some bytes!"})}})
	assert_receive {^port, {:data, data}}
	assert {:ok, _} = :erlang.binary_to_term(data)
	end

	test "fails with non existent file", %{port: port} do
	send(port, {self(), {:command, :erlang.term_to_binary({:file, "/path/to/nowhere"})}})
	assert_receive {^port, {:data, data}}
	assert {:error, _} = :erlang.binary_to_term(data)
	end

	test "works with big file path", %{port: port} do
	- file = too_big() <> "/a"
	- File.mkdir_p!(too_big())
	- File.touch!(file)
	- on_exit(fn -> File.rm_rf!("/tmp/testmagicex/") end)
	- send(port, {self(), {:command, :erlang.term_to_binary({:file, file})}})
	+ # Test with longest valid path.
	+ {dir, bigfile} = too_big(@tmp_path, "/a")
	+ File.mkdir_p!(dir)
	+ File.touch!(bigfile)
	+ on_exit(fn -> File.rm_rf!(@tmp_path) end)
	+ send(port, {self(), {:command, :erlang.term_to_binary({:file, bigfile})}})
	assert_receive {^port, {:data, data}}
	assert {:ok, _} = :erlang.binary_to_term(data)
	refute_receive _
	- file = too_big() <> "/aaaaaaaaaa"
	+
	+ # This path should be long enough for buffers, but larger than a valid path name. Magic will return an errno 36.
	+ file = @tmp_path <> String.duplicate("a", 256)
	+ send(port, {self(), {:command, :erlang.term_to_binary({:file, file})}})
	+ assert_receive {^port, {:data, data}}
	+ assert {:error, {36, _}} = :erlang.binary_to_term(data)
	+ refute_receive _
	+ # Theses filename should be too big for the path buffer.
	+ file = bigfile <> "aaaaaaaaaa"
	+ send(port, {self(), {:command, :erlang.term_to_binary({:file, file})}})
	+ assert_receive {^port, {:data, data}}
	+ assert {:error, :enametoolong} = :erlang.binary_to_term(data)
	+ refute_receive _
	+ # This call should be larger than the COMMAND_BUFFER_SIZE. Ensure nothing bad happens!
	+ file = String.duplicate(bigfile, 4)
	send(port, {self(), {:command, :erlang.term_to_binary({:file, file})}})
	assert_receive {^port, {:data, data}}
	assert {:error, :badarg} = :erlang.binary_to_term(data)
	refute_receive _
	+ # We re-run a valid call to ensure the buffer/... haven't been corrupted in port land.
	+ send(port, {self(), {:command, :erlang.term_to_binary({:file, bigfile})}})
	+ assert_receive {^port, {:data, data}}
	+ assert {:ok, _} = :erlang.binary_to_term(data)
	+ refute_receive _
	end
	end

	def assert_ready(port) do
	assert_receive {^port, {:data, data}}
	assert :ready == :erlang.binary_to_term(data)
	end

	- def too_big do
	- "/tmp/testmagicex/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa/aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa"
	+ def too_big(path, filename, limit \\ 4095) do
	+ last_len = byte_size(filename)
	+ path_len = byte_size(path)
	+ needed = limit - (last_len + path_len)
	+ extra = make_too_big(needed, "")
	+ {path <> extra, path <> extra <> filename}
	+ end
	+
	+ def make_too_big(needed, acc) when needed <= 255 do
	+ acc <> "/" <> String.duplicate("a", needed - 1)
	+ end
	+
	+ def make_too_big(needed, acc) do
	+ acc = acc <> "/" <> String.duplicate("a", 254)
	+ make_too_big(needed - 255, acc)
	end
	end

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