Files
libguestfs/generator/erlang.ml
Richard W.M. Jones 0ff73a42c7 generator: Implement struct FDevice type
This acts just like FString except that we do reverse device name
translation on it.  The only use is in the 'pvs-full' API where we
will use it (in a subsequent commit) to reverse translate the pv_name
field (a device name) before returning it from the daemon.

Compare this to the 'pvs' API which also returns a list of device
names, but using the generator's 'RStructList (RDevice,...)'  return
type, where RDevice is similarly reverse translated.

Note in the library-side bindings, because the name has already been
translated in the daemon, we just treat it exactly the same as
FString.  The vast majority of this patch is this mechanical change.
2025-04-16 12:27:07 +01:00

567 lines
18 KiB
OCaml

(* libguestfs
* Copyright (C) 2011 Red Hat Inc.
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*)
(* Please read generator/README first. *)
open Printf
open Std_utils
open Types
open Utils
open Pr
open Docstrings
open Optgroups
open Actions
open Structs
open C
open Events
let generate_header = generate_header ~inputs:["generator/erlang.ml"]
let rec generate_erlang_erl () =
generate_header ErlangStyle LGPLv2plus;
pr "-module(guestfs).\n";
pr "\n";
pr "-export([create/0, create/1, close/1, init/1]).\n";
pr "\n";
(* Export the public actions. *)
List.iter (
fun { name; style = _, args, optargs; non_c_aliases = aliases } ->
let nr_args = List.length args in
let export name =
if optargs = [] then
pr "-export([%s/%d]).\n" name (nr_args+1)
else
pr "-export([%s/%d, %s/%d]).\n" name (nr_args+1) name (nr_args+2)
in
export name;
List.iter export aliases
) (actions |> external_functions |> sort);
pr "\n";
pr "\
create() ->
create(\"erl-guestfs\").
create(ExtProg) ->
G = spawn(?MODULE, init, [ExtProg]),
{ok, G}.
close(G) ->
G ! close,
ok.
call_port(G, Args) ->
G ! {call, self(), Args},
receive
{guestfs, Result} ->
Result
end.
init(ExtProg) ->
process_flag(trap_exit, true),
Port = open_port({spawn, ExtProg}, [{packet, 4}, binary]),
loop(Port).
loop(Port) ->
receive
{call, Caller, Args} ->
Port ! { self(), {command, term_to_binary(Args)}},
receive
{Port, {data, Result}} ->
Caller ! { guestfs, binary_to_term(Result)}
end,
loop(Port);
close ->
port_close(Port),
exit(normal);
{ 'EXIT', Port, _ } ->
exit(port_terminated)
end.
";
(* These bindings just marshal the parameters and call the back-end
* process which dispatches them to the port.
*)
List.iter (
fun { name; style = _, args, optargs; non_c_aliases = aliases } ->
pr "%s(G" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
if optargs <> [] then
pr ", Optargs";
pr ") ->\n";
pr " call_port(G, {%s" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
if optargs <> [] then
pr ", Optargs";
pr "}).\n";
(* For functions with optional arguments, make a variant that
* has no optarg array, which just calls the function above with
* an empty list as the final arg.
*)
if optargs <> [] then (
pr "%s(G" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
pr ") ->\n";
pr " %s(G" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
pr ", []";
pr ").\n"
);
(* Aliases. *)
List.iter (
fun alias ->
pr "%s(G" alias;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
if optargs <> [] then
pr ", Optargs";
pr ") ->\n";
pr " %s(G" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
if optargs <> [] then
pr ", Optargs";
pr ").\n";
if optargs <> [] then (
pr "%s(G" alias;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
pr ") ->\n";
pr " %s(G" name;
List.iter (
fun arg ->
pr ", %s" (String.capitalize_ascii (name_of_argt arg))
) args;
pr ").\n"
)
) aliases;
pr "\n"
) (actions |> external_functions |> sort)
and generate_erlang_actions_h () =
generate_header CStyle GPLv2plus;
pr "\
#ifndef GUESTFS_ERLANG_ACTIONS_H_
#define GUESTFS_ERLANG_ACTIONS_H_
extern guestfs_h *g;
extern int dispatch (ei_x_buff *retbuff, const char *buff, int *index);
extern int make_error (ei_x_buff *retbuff, const char *funname);
extern int unknown_optarg (ei_x_buff *retbuff, const char *funname, const char *optargname);
extern int unknown_function (ei_x_buff *retbuff, const char *fun);
extern int make_string_list (ei_x_buff *buff, char **r);
extern int make_table (ei_x_buff *buff, char **r);
extern int make_bool (ei_x_buff *buff, int r);
extern int atom_equals (const char *atom, const char *name);
extern int decode_string_list (const char *buff, int *index, char ***res);
extern int decode_string (const char *buff, int *index, char **res);
extern int decode_binary (const char *buff, int *index, char **res, size_t *size);
extern int decode_bool (const char *buff, int *index, int *res);
extern int decode_int (const char *buff, int *index, int *res);
extern int decode_int64 (const char *buff, int *index, int64_t *res);
";
let emit_copy_list_decl typ =
pr "int make_%s_list (ei_x_buff *buff, const struct guestfs_%s_list *%ss);\n"
typ typ typ;
in
List.iter (
fun { s_name = typ; s_cols = cols } ->
pr "int make_%s (ei_x_buff *buff, const struct guestfs_%s *%s);\n" typ typ typ;
) external_structs;
List.iter (
function
| typ, (RStructListOnly | RStructAndList) ->
emit_copy_list_decl typ
| typ, _ -> () (* empty *)
) (rstructs_used_by (actions |> external_functions));
pr "\n";
List.iter (
fun { name } ->
pr "int run_%s (ei_x_buff *retbuff, const char *buff, int *index);\n" name
) (actions |> external_functions |> sort);
pr "\n";
pr "#endif /* GUESTFS_ERLANG_ACTIONS_H_ */\n"
and generate_erlang_structs () =
generate_header CStyle GPLv2plus;
pr "\
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <ei.h>
#include \"guestfs.h\"
#include \"guestfs-utils.h\"
#include \"actions.h\"
";
(* Struct copy functions. *)
let emit_copy_list_function typ =
pr "\n";
pr "int\n";
pr "make_%s_list (ei_x_buff *buff, const struct guestfs_%s_list *%ss)\n" typ typ typ;
pr "{\n";
pr " size_t len = %ss->len;\n" typ;
pr " size_t i;\n";
pr "\n";
pr " if (ei_x_encode_list_header (buff, len) != 0) return -1;\n";
pr " for (i = 0; i < len; ++i) {\n";
pr " if (make_%s (buff, &%ss->val[i]) != 0) return -1;\n" typ typ;
pr " }\n";
pr " if (len > 0)\n";
pr " if (ei_x_encode_empty_list (buff) != 0) return -1;\n";
pr "\n";
pr " return 0;\n";
pr "}\n";
in
List.iter (
fun { s_name = typ; s_cols = cols } ->
pr "\n";
pr "int\n";
pr "make_%s (ei_x_buff *buff, const struct guestfs_%s *%s)\n" typ typ typ;
pr "{\n";
pr " if (ei_x_encode_list_header (buff, %d) !=0) return -1;\n" (List.length cols);
pr "\n";
List.iteri (
fun i col ->
(match col with
| name, (FString|FDevice) ->
pr " if (ei_x_encode_string (buff, %s->%s) != 0) return -1;\n" typ name
| name, FBuffer ->
pr " if (ei_x_encode_string_len (buff, %s->%s, %s->%s_len) != 0) return -1;\n"
typ name typ name
| name, FUUID ->
pr " if (ei_x_encode_string_len (buff, %s->%s, 32) != 0) return -1;\n" typ name
| name, (FBytes|FInt64|FUInt64) ->
pr " if (ei_x_encode_longlong (buff, %s->%s) != 0) return -1;\n" typ name
| name, (FInt32|FUInt32) ->
pr " if (ei_x_encode_long (buff, %s->%s) != 0) return -1;\n" typ name
| name, FOptPercent ->
pr " if (%s->%s >= 0) {\n" typ name;
pr " if (ei_x_encode_double (buff, %s->%s) != 0) return -1;\n" typ name;
pr " } else {\n";
pr " if (ei_x_encode_atom (buff, \"undefined\") != 0) return -1;\n";
pr " }\n"
| name, FChar ->
pr " if (ei_x_encode_char (buff, %s->%s) != 0) return -1;\n" typ name
);
) cols;
if cols <> [] then (
pr "\n";
pr " if (ei_x_encode_empty_list (buff) != 0) return -1;\n"
);
pr "\n";
pr " return 0;\n";
pr "}\n";
) external_structs;
(* Emit a copy_TYPE_list function definition only if that function is used. *)
List.iter (
function
| typ, (RStructListOnly | RStructAndList) ->
(* generate the function for typ *)
emit_copy_list_function typ
| typ, _ -> () (* empty *)
) (rstructs_used_by (actions |> external_functions));
and generate_erlang_actions actions () =
generate_header CStyle GPLv2plus;
pr "\
#include <config.h>
/* It is safe to call deprecated functions from this file. */
#define GUESTFS_NO_WARN_DEPRECATED
#undef GUESTFS_NO_DEPRECATED
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <ei.h>
#include \"guestfs.h\"
#include \"guestfs-utils.h\"
#include \"actions.h\"
";
(* The wrapper functions. *)
List.iter (
fun { name; style = (ret, args, optargs as style);
c_function; c_optarg_prefix } ->
pr "\n";
pr "int\n";
pr "run_%s (ei_x_buff *retbuff, const char *buff, int *idx)\n" name;
pr "{\n";
List.iteri (
fun i ->
function
| String (_, n) ->
pr " CLEANUP_FREE char *%s;\n" n;
pr " if (decode_string (buff, idx, &%s) != 0) return -1;\n" n
| OptString n ->
pr " CLEANUP_FREE char *%s;\n" n;
pr " char %s_opt[MAXATOMLEN];\n" n;
pr " if (ei_decode_atom(buff, idx, %s_opt) == 0) {\n" n;
pr " if (atom_equals (%s_opt, \"undefined\"))\n" n;
pr " %s = NULL;\n" n;
pr " else\n";
pr " %s = %s_opt;\n" n n;
pr " } else {\n";
pr " if (decode_string (buff, idx, &%s) != 0) return -1;\n" n;
pr " }\n"
| BufferIn n ->
pr " CLEANUP_FREE char *%s;\n" n;
pr " size_t %s_size;\n" n;
pr " if (decode_binary (buff, idx, &%s, &%s_size) != 0) return -1;\n" n n
| StringList (_, n) ->
pr " CLEANUP_FREE_STRING_LIST char **%s;\n" n;
pr " if (decode_string_list (buff, idx, &%s) != 0) return -1;\n" n
| Bool n ->
pr " int %s;\n" n;
pr " if (decode_bool (buff, idx, &%s) != 0) return -1;\n" n
| Int n ->
pr " int %s;\n" n;
pr " if (decode_int (buff, idx, &%s) != 0) return -1;\n" n
| Int64 n ->
pr " int64_t %s;\n" n;
pr " if (decode_int64 (buff, idx, &%s) != 0) return -1;\n" n
| Pointer (t, n) ->
pr " void * /* %s */ %s = POINTER_NOT_IMPLEMENTED (\"%s\");\n" t n t
) args;
(* Optional arguments. *)
if optargs <> [] then (
pr "\n";
pr " struct %s optargs_s = { .bitmask = 0 };\n" c_function;
pr " struct %s *optargs = &optargs_s;\n" c_function;
pr " int optargsize;\n";
pr " if (ei_decode_list_header (buff, idx, &optargsize) != 0) return -1;\n";
pr " for (int i = 0; i < optargsize; i++) {\n";
pr " int hd;\n";
pr " if (ei_decode_tuple_header (buff, idx, &hd) != 0) return -1;\n";
pr " char hd_name[MAXATOMLEN];\n";
pr " if (ei_decode_atom (buff, idx, hd_name) != 0) return -1;\n";
pr "\n";
List.iter (
fun argt ->
let n = name_of_optargt argt in
let uc_n = String.uppercase_ascii n in
pr " if (atom_equals (hd_name, \"%s\")) {\n" n;
pr " optargs_s.bitmask |= %s_%s_BITMASK;\n"
c_optarg_prefix uc_n;
pr " ";
(match argt with
| OBool _ -> pr "if (decode_bool (buff, idx, &optargs_s.%s) != 0) return -1;" n
| OInt _ -> pr "if (decode_int (buff, idx, &optargs_s.%s) != 0) return -1" n
| OInt64 _ -> pr "if (decode_int64 (buff, idx, &optargs_s.%s) != 0) return -1" n
| OString _ -> pr "if (decode_string (buff, idx, (char **) &optargs_s.%s) != 0) return -1" n
| OStringList n -> pr "if (decode_string_list (buff, idx, (char ***) &optargs_s.%s) != 0) return -1" n
);
pr ";\n";
pr " }\n";
pr " else\n";
) optargs;
pr " return unknown_optarg (retbuff, \"%s\", hd_name);\n" name;
pr " }\n";
pr " if (optargsize > 0 && buff[*idx] == ERL_NIL_EXT)\n";
pr " (*idx)++;\n";
pr "\n";
);
(match ret with
| RErr -> pr " int r;\n"
| RInt _ -> pr " int r;\n"
| RInt64 _ -> pr " int64_t r;\n"
| RBool _ -> pr " int r;\n"
| RConstString _ | RConstOptString _ ->
pr " const char *r;\n"
| RString _ -> pr " char *r;\n"
| RStringList _ ->
pr " char **r;\n"
| RStruct (_, typ) ->
pr " struct guestfs_%s *r;\n" typ
| RStructList (_, typ) ->
pr " struct guestfs_%s_list *r;\n" typ
| RHashtable _ ->
pr " char **r;\n"
| RBufferOut _ ->
pr " char *r;\n";
pr " size_t size;\n"
);
pr "\n";
pr " r = %s " c_function;
generate_c_call_args ~handle:"g" style;
pr ";\n";
(* Free strings if we copied them above. *)
List.iter (
function
| OBool _ | OInt _ | OInt64 _ -> ()
| OString n ->
let uc_n = String.uppercase_ascii n in
pr " if ((optargs_s.bitmask & %s_%s_BITMASK))\n"
c_optarg_prefix uc_n;
pr " free ((char *) optargs_s.%s);\n" n
| OStringList n ->
let uc_n = String.uppercase_ascii n in
pr " if ((optargs_s.bitmask & %s_%s_BITMASK))\n"
c_optarg_prefix uc_n;
pr " guestfs_int_free_string_list ((char **) optargs_s.%s);\n" n
) optargs;
(match errcode_of_ret ret with
| `CannotReturnError -> ()
| `ErrorIsMinusOne ->
pr " if (r == -1)\n";
pr " return make_error (retbuff, \"%s\");\n" name;
| `ErrorIsNULL ->
pr " if (r == NULL)\n";
pr " return make_error (retbuff, \"%s\");\n" name;
);
pr "\n";
(match ret with
| RErr -> pr " if (ei_x_encode_atom (retbuff, \"ok\") != 0) return -1;\n"
| RInt _ -> pr " if (ei_x_encode_long (retbuff, r) != 0) return -1;\n"
| RInt64 _ -> pr " if (ei_x_encode_longlong (retbuff, r) != 0) return -1;\n"
| RBool _ -> pr " if (make_bool (retbuff, r) != 0) return -1;\n"
| RConstString _ -> pr " if (ei_x_encode_string (retbuff, r) != 0) return -1;\n"
| RConstOptString _ ->
pr " if (r) {\n";
pr " if (ei_x_encode_string (retbuff, r) != 0) return -1;\n";
pr " } else {\n";
pr " if (ei_x_encode_atom (retbuff, \"undefined\") != 0) return -1;\n";
pr " }\n"
| RString _ ->
pr " if (ei_x_encode_string (retbuff, r) != 0) return -1;\n";
pr " free (r);\n";
| RStringList _ ->
pr " if (make_string_list (retbuff, r) != 0) return -1;\n";
pr " guestfs_int_free_string_list (r);\n"
| RStruct (_, typ) ->
pr " if (make_%s (retbuff, r) != 0) return -1;\n" typ;
pr " guestfs_free_%s (r);\n" typ
| RStructList (_, typ) ->
pr " if (make_%s_list (retbuff, r) != 0) return -1;\n" typ;
pr " guestfs_free_%s_list (r);\n" typ
| RHashtable _ ->
pr " if (make_table (retbuff, r) != 0) return -1;\n";
pr " guestfs_int_free_string_list (r);\n"
| RBufferOut _ ->
pr " if (ei_x_encode_binary (retbuff, r, size) != 0) return -1;\n";
pr " free (r);\n";
);
pr " return 0;\n";
pr "}\n";
) (actions |> external_functions |> sort);
and generate_erlang_dispatch () =
generate_header CStyle GPLv2plus;
pr "\
#include <config.h>
#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <string.h>
#include <errno.h>
#include <ei.h>
#include \"guestfs.h\"
#include \"guestfs-utils.h\"
#include \"actions.h\"
int
dispatch (ei_x_buff *retbuff, const char *buff, int *index)
{
int arity;
char fun[MAXATOMLEN];
if (ei_decode_tuple_header (buff, index, &arity) != 0) return -1;
if (ei_decode_atom (buff, index, fun) != 0) return -1;
/* XXX We should use gperf here. */
";
List.iter (
fun { name; style = ret, args, optargs } ->
pr "if (atom_equals (fun, \"%s\"))\n" name;
pr " return run_%s (retbuff, buff, index);\n" name;
pr " else ";
) (actions |> external_functions |> sort);
pr "return unknown_function (retbuff, fun);
}
";