Small updates to the generator.

[libguestfs.git] / src / generator.ml

diff --git a/src/generator.ml b/src/generator.ml
index 02fe691..5868e17 100755 (executable)
--- a/src/generator.ml
+++ b/src/generator.ml
@@ -26,13 +26,22 @@
 
 open Printf
 
 
 open Printf
 

-type styles =
-  | Int_Void           (* int foo (guestfs_h); *)
-  | Int_String         (* int foo (guestfs_h, const char * ); *)
-  | Int_StringString   (* int foo (guestfs_h, const char *, const char * ); *)
+type style = ret * args
+and ret =
+    (* "Err" as a return value means an int used as a simple error
+     * indication, ie. 0 or -1.
+     *)
+  | Err
+and args =
+    (* 0 arguments, 1 argument, etc. The guestfs_h param is implicit. *)
+  | P0
+  | P1 of argt
+  | P2 of argt * argt
+and argt =
+  | String of string   (* const char *name, cannot be NULL *)

 
 let functions = [
 
 let functions = [

-  ("mount", Int_StringString, [|"device"; "mountpoint"|],
+  ("mount", (Err, P2 (String "device", String "mountpoint")), 1,

    "Mount a guest disk at a position in the filesystem",
    "\
 Mount a guest disk at a position in the filesystem.  Block devices
    "Mount a guest disk at a position in the filesystem",
    "\
 Mount a guest disk at a position in the filesystem.  Block devices


@@ -44,9 +53,15 @@ names can be used.
 The rules are the same as for L<mount(2)>:  A filesystem must
 first be mounted on C</> before others can be mounted.  Other
 filesystems can only be mounted on directories which already
 The rules are the same as for L<mount(2)>:  A filesystem must
 first be mounted on C</> before others can be mounted.  Other
 filesystems can only be mounted on directories which already

-exist.");
+exist.

 
 

-  ("sync", Int_Void, [||],
+The mounted filesystem is writable, if we have sufficient permissions
+on the underlying device.
+
+The filesystem options C<sync> and C<noatime> are set with this
+call, in order to improve reliability.");
+
+  ("sync", (Err, P0), 2,

    "Sync disks, writes are flushed through to the disk image",
    "\
 This syncs the disk, so that any writes are flushed through to the
    "Sync disks, writes are flushed through to the disk image",
    "\
 This syncs the disk, so that any writes are flushed through to the


@@ -55,7 +70,7 @@ underlying disk image.
 You should always call this if you have modified a disk image, before
 calling C<guestfs_close>.");
 
 You should always call this if you have modified a disk image, before
 calling C<guestfs_close>.");
 

-  ("touch", Int_String, [|"path"|],
+  ("touch", (Err, P1 (String "path")), 3,

    "Update file timestamps or create a new file",
    "\
 Touch acts like the L<touch(1)> command.  It can be used to
    "Update file timestamps or create a new file",
    "\
 Touch acts like the L<touch(1)> command.  It can be used to


@@ -67,6 +82,11 @@ to create a new zero-length file.");
 let chan = ref stdout
 let pr fs = ksprintf (output_string !chan) fs
 
 let chan = ref stdout
 let pr fs = ksprintf (output_string !chan) fs
 

+let iter_args f = function
+  | P0 -> ()
+  | P1 arg1 -> f arg1
+  | P2 (arg1, arg2) -> f arg1; f arg2
+

 type comment_style = CStyle | HashStyle | OCamlStyle
 type license = GPLv2 | LGPLv2
 
 type comment_style = CStyle | HashStyle | OCamlStyle
 type license = GPLv2 | LGPLv2
 


@@ -77,8 +97,8 @@ let rec generate_header comment license =
     | HashStyle ->  pr "# ";  "#"
     | OCamlStyle -> pr "(* "; " *" in
   pr "libguestfs generated file\n";
     | HashStyle ->  pr "# ";  "#"
     | OCamlStyle -> pr "(* "; " *" in
   pr "libguestfs generated file\n";

-  pr "%s WARNING: This file is generated by 'src/generator.ml'.\n" c;
-  pr "%s Any changes you make to this file will be lost.\n" c;
+  pr "%s WARNING: THIS FILE IS GENERATED BY 'src/generator.ml'.\n" c;
+  pr "%s ANY CHANGES YOU MAKE TO THIS FILE WILL BE LOST.\n" c;

   pr "%s\n" c;
   pr "%s Copyright (C) 2009 Red Hat Inc.\n" c;
   pr "%s\n" c;
   pr "%s\n" c;
   pr "%s Copyright (C) 2009 Red Hat Inc.\n" c;
   pr "%s\n" c;


@@ -123,45 +143,356 @@ let rec generate_header comment license =
 (* Generate the pod documentation for the C API. *)
 and generate_pod () =
   List.iter (
 (* Generate the pod documentation for the C API. *)
 and generate_pod () =
   List.iter (

-    fun (shortname, style, params, _, longdesc) ->
+    fun (shortname, style, _, _, longdesc) ->

       let name = "guestfs_" ^ shortname in
       pr "=head2 %s\n\n" name;
       pr " ";
       let name = "guestfs_" ^ shortname in
       pr "=head2 %s\n\n" name;
       pr " ";

-      generate_prototype ~extern:false name style params;
+      generate_prototype ~extern:false ~handle:"handle" name style;

       pr "\n\n";
       pr "\n\n";

-      pr "%s\n\n" longdesc
+      pr "%s\n\n" longdesc;
+      (match style with
+       | (Err, _) ->
+          pr "This function return 0 on success or -1 on error.\n\n"
+      );

   ) functions
 
 (* Generate the protocol (XDR) file. *)
 and generate_xdr () =
   generate_header CStyle LGPLv2;
   ) functions
 
 (* Generate the protocol (XDR) file. *)
 and generate_xdr () =
   generate_header CStyle LGPLv2;

+
+  List.iter (
+    fun (shortname, style, _, _, _) ->
+      let name = "guestfs_" ^ shortname in
+      pr "/* %s */\n\n" name;
+      (match style with
+       | (_, P0) -> ()
+       | (_, args) ->
+          pr "struct %s_args {\n" name;
+          iter_args (
+            function
+            | String name -> pr "  string %s<>;\n" name
+          ) args;
+          pr "};\n\n"
+      );
+      (match style with
+       | (Err, _) -> () 
+          (* | ... -> pr "struct %s_ret ...\n" name; *)
+      );
+  ) functions;
+
+  (* Table of procedure numbers. *)
+  pr "enum guestfs_procedure {\n";
+  List.iter (
+    fun (shortname, _, proc_nr, _, _) ->
+      pr "  GUESTFS_PROC_%s = %d,\n" (String.uppercase shortname) proc_nr
+  ) functions;
+  pr "  GUESTFS_PROC_dummy\n"; (* so we don't have a "hanging comma" *)
+  pr "};\n";
+  pr "\n";
+
+  (* Having to choose a maximum message size is annoying for several
+   * reasons (it limits what we can do in the API), but it (a) makes
+   * the protocol a lot simpler, and (b) provides a bound on the size
+   * of the daemon which operates in limited memory space.  For large
+   * file transfers you should use FTP.
+   *)
+  pr "const GUESTFS_MESSAGE_MAX = %d;\n" (4 * 1024 * 1024);
+  pr "\n";
+
+  (* Message header, etc. *)
+  pr "\
+const GUESTFS_PROGRAM = 0x2000F5F5;
+const GUESTFS_PROTOCOL_VERSION = 1;
+
+enum guestfs_message_direction {
+  GUESTFS_DIRECTION_CALL = 0,        /* client -> daemon */
+  GUESTFS_DIRECTION_REPLY = 1        /* daemon -> client */
+};
+
+enum guestfs_message_status {
+  GUESTFS_STATUS_OK = 0,
+  GUESTFS_STATUS_ERROR = 1
+};
+
+const GUESTFS_ERROR_LEN = 256;
+
+struct guestfs_message_error {
+  string error<GUESTFS_ERROR_LEN>;   /* error message */
+};
+
+struct guestfs_message_header {
+  unsigned prog;                     /* GUESTFS_PROGRAM */
+  unsigned vers;                     /* GUESTFS_PROTOCOL_VERSION */
+  guestfs_procedure proc;            /* GUESTFS_PROC_x */
+  guestfs_message_direction direction;
+  unsigned serial;                   /* message serial number */
+  guestfs_message_status status;
+};
+"
+
+(* Generate the guestfs-actions.h file. *)
+and generate_actions_h () =
+  generate_header CStyle LGPLv2;
+  List.iter (
+    fun (shortname, style, _, _, _) ->
+      let name = "guestfs_" ^ shortname in
+      generate_prototype ~single_line:true ~newline:true ~handle:"handle"
+       name style
+  ) functions
+
+(* Generate the client-side dispatch stubs. *)
+and generate_client_actions () =
+  generate_header CStyle LGPLv2;

   List.iter (
   List.iter (

-    fun (shortname, style, params, _, longdesc) ->
+    fun (shortname, style, _, _, _) ->

       let name = "guestfs_" ^ shortname in
       let name = "guestfs_" ^ shortname in

-      pr "/* %s */\n" name;

 
 

+      (* Generate the return value struct. *)
+      pr "struct %s_rv {\n" shortname;
+      pr "  int cb_done;  /* flag to indicate callback was called */\n";
+      pr "  struct guestfs_message_header hdr;\n";
+      pr "  struct guestfs_message_error err;\n";
+      (match style with
+       | (Err, _) -> ()
+    (* | _ -> pr "  struct %s_ret ret;\n" name; *)
+      );
+      pr "};\n\n";
+
+      (* Generate the callback function. *)
+      pr "static void %s_cb (guestfs_h *g, void *data, XDR *xdr)\n" shortname;
+      pr "{\n";
+      pr "  struct %s_rv *rv = (struct %s_rv *) data;\n" shortname shortname;
+      pr "\n";
+      pr "  if (!xdr_guestfs_message_header (xdr, &rv->hdr)) {\n";
+      pr "    error (g, \"%s: failed to parse reply header\");\n" name;
+      pr "    return;\n";
+      pr "  }\n";
+      pr "  if (rv->hdr.status == GUESTFS_STATUS_ERROR) {\n";
+      pr "    if (!xdr_guestfs_message_error (xdr, &rv->err)) {\n";
+      pr "      error (g, \"%s: failed to parse reply error\");\n" name;
+      pr "      return;\n";
+      pr "    }\n";
+      pr "    goto done;\n";
+      pr "  }\n";
+
+      (match style with
+       | (Err, _) -> ()
+    (* |  _ -> pr "  if (!xdr_%s_ret (&xdr, &rv->ret)) ..." *)
+      );
+
+      pr " done:\n";
+      pr "  rv->cb_done = 1;\n";
+      pr "  main_loop.main_loop_quit (g);\n";
+      pr "}\n\n";
+
+      (* Generate the action stub. *)
+      generate_prototype ~extern:false ~semicolon:false ~newline:true
+       ~handle:"g" name style;
+
+      let error_code =
+       match style with
+       | (Err, _) -> "-1" in
+
+      pr "{\n";
+
+      (match style with
+       | (_, P0) -> ()
+       | _ -> pr "  struct %s_args args;\n" name
+      );
+
+      pr "  struct %s_rv rv;\n" shortname;
+      pr "  int serial;\n";
+      pr "\n";
+      pr "  if (g->state != READY) {\n";
+      pr "    error (g, \"%s called from the wrong state, %%d != READY\",\n"
+       name;
+      pr "      g->state);\n";
+      pr "    return %s;\n" error_code;
+      pr "  }\n";
+      pr "\n";
+      pr "  memset (&rv, 0, sizeof rv);\n";
+      pr "\n";
+
+      (match style with
+       | (_, P0) ->
+          pr "  serial = dispatch (g, GUESTFS_PROC_%s, NULL, NULL);\n"
+            (String.uppercase shortname)
+       | (_, args) ->
+          iter_args (
+            function
+            | String name -> pr "  args.%s = (char *) %s;\n" name name
+          ) args;
+          pr "  serial = dispatch (g, GUESTFS_PROC_%s,\n"
+            (String.uppercase shortname);
+          pr "                     (xdrproc_t) xdr_%s_args, (char *) &args);\n"
+            name;
+      );
+      pr "  if (serial == -1)\n";
+      pr "    return %s;\n" error_code;
+      pr "\n";
+
+      pr "  rv.cb_done = 0;\n";
+      pr "  g->reply_cb_internal = %s_cb;\n" shortname;
+      pr "  g->reply_cb_internal_data = &rv;\n";
+      pr "  main_loop.main_loop_run (g);\n";
+      pr "  g->reply_cb_internal = NULL;\n";
+      pr "  g->reply_cb_internal_data = NULL;\n";
+      pr "  if (!rv.cb_done) {\n";
+      pr "    error (g, \"%s failed, see earlier error messages\");\n" name;
+      pr "    return %s;\n" error_code;
+      pr "  }\n";
+      pr "\n";
+
+      pr "  if (check_reply_header (g, &rv.hdr, GUESTFS_PROC_%s, serial) == -1)\n"
+       (String.uppercase shortname);
+      pr "    return %s;\n" error_code;
+      pr "\n";

 
 

+      pr "  if (rv.hdr.status == GUESTFS_STATUS_ERROR) {\n";
+      pr "    error (g, \"%%s\", rv.err.error);\n";
+      pr "    return %s;\n" error_code;
+      pr "  }\n";

       pr "\n";
       pr "\n";

+
+      (match style with
+       | (Err, _) -> pr "  return 0;\n"
+      );
+
+      pr "}\n\n"
+  ) functions
+
+(* Generate daemon/actions.h. *)
+and generate_daemon_actions_h () =
+  generate_header CStyle GPLv2;
+  List.iter (
+    fun (name, style, _, _, _) ->
+      generate_prototype ~single_line:true ~newline:true ("do_" ^ name) style;

   ) functions
 
   ) functions
 

-(* Generate a single line prototype. *)
-and generate_prototype ~extern ?(semi = true) ?(handle = "handle")
-    name style params =
+(* Generate the server-side stubs. *)
+and generate_daemon_actions () =
+  generate_header CStyle GPLv2;
+
+  pr "#include <rpc/types.h>\n";
+  pr "#include <rpc/xdr.h>\n";
+  pr "#include \"daemon.h\"\n";
+  pr "#include \"../src/guestfs_protocol.h\"\n";
+  pr "#include \"actions.h\"\n";
+  pr "\n";
+
+  List.iter (
+    fun (name, style, _, _, _) ->
+      (* Generate server-side stubs. *)
+      pr "static void %s_stub (XDR *xdr_in)\n" name;
+      pr "{\n";
+      let error_code =
+       match style with
+       | (Err, _) -> pr "  int r;\n"; "-1" in
+      (match style with
+       | (_, P0) -> ()
+       | (_, args) ->
+          pr "  struct guestfs_%s_args args;\n" name;
+          iter_args (
+            function
+            | String name -> pr "  const char *%s;\n" name
+          ) args
+      );
+      pr "\n";
+
+      (match style with
+       | (_, P0) -> ()
+       | (_, args) ->
+          pr "  memset (&args, 0, sizeof args);\n";
+          pr "\n";
+          pr "  if (!xdr_guestfs_%s_args (xdr_in, &args)) {\n" name;
+          pr "    reply_with_error (\"%s: daemon failed to decode procedure arguments\");\n" name;
+          pr "    return;\n";
+          pr "  }\n";
+          iter_args (
+            function
+            | String name -> pr "  %s = args.%s;\n" name name
+          ) args;
+          pr "\n"
+      );
+
+      pr "  r = do_%s " name;
+      generate_call_args style;
+      pr ";\n";
+
+      pr "  if (r == %s)\n" error_code;
+      pr "    /* do_%s has already called reply_with_error, so just return */\n" name;
+      pr "    return;\n";
+      pr "\n";
+
+      (match style with
+       | (Err, _) -> pr "  reply (NULL, NULL);\n"
+      );
+
+      pr "}\n\n";
+  ) functions;
+
+  (* Dispatch function. *)
+  pr "void dispatch_incoming_message (XDR *xdr_in)\n";
+  pr "{\n";
+  pr "  switch (proc_nr) {\n";
+
+  List.iter (
+    fun (name, style, _, _, _) ->
+      pr "    case GUESTFS_PROC_%s:\n" (String.uppercase name);
+      pr "      %s_stub (xdr_in);\n" name;
+      pr "      break;\n"
+  ) functions;
+
+  pr "    default:\n";
+  pr "      reply_with_error (\"dispatch_incoming_message: unknown procedure number %%d\", proc_nr);\n";
+  pr "  }\n";
+  pr "}\n";
+
+(* Generate a C function prototype. *)
+and generate_prototype ?(extern = true) ?(static = false) ?(semicolon = true)
+    ?(single_line = false) ?(newline = false)
+    ?handle name style =

   if extern then pr "extern ";
   if extern then pr "extern ";

+  if static then pr "static ";

   (match style with
   (match style with

-   | Int_Void | Int_String | Int_StringString -> pr "int "
+   | (Err, _) -> pr "int "

   );
   );

-  pr "%s (guestfs_h *%s" name handle;
-  (match style with
-   | Int_Void -> ()
-   | Int_String ->
-       pr ", const char *%s" params.(0)
-   | Int_StringString ->
-       pr ", const char *%s" params.(0);
-       pr ", const char *%s" params.(1)
+  pr "%s (" name;
+  let comma = ref false in
+  (match handle with
+   | None -> ()
+   | Some handle -> pr "guestfs_h *%s" handle; comma := true

   );
   );

+  let next () =
+    if !comma then (
+      if single_line then pr ", " else pr ",\n\t\t"
+    );
+    comma := true
+  in
+  iter_args (
+    function
+    | String name -> next (); pr "const char *%s" name
+  ) (snd style);

   pr ")";
   pr ")";

-  if semi then pr ";"
+  if semicolon then pr ";";
+  if newline then pr "\n"
+
+(* Generate C call arguments, eg "(handle, foo, bar)" *)
+and generate_call_args ?handle style =
+  pr "(";
+  let comma = ref false in
+  (match handle with
+   | None -> ()
+   | Some handle -> pr "%s" handle; comma := true
+  );
+  iter_args (
+    fun arg ->
+      if !comma then pr ", ";
+      comma := true;
+      match arg with
+      | String name -> pr "%s" name
+  ) (snd style);
+  pr ")"

 
 let output_to filename =
   let filename_new = filename ^ ".new" in
 
 let output_to filename =
   let filename_new = filename ^ ".new" in


@@ -169,16 +500,33 @@ let output_to filename =
   let close () =
     close_out !chan;
     chan := stdout;
   let close () =
     close_out !chan;
     chan := stdout;

-    Unix.rename filename_new filename
+    Unix.rename filename_new filename;
+    printf "written %s\n%!" filename;

   in
   close
 
 (* Main program. *)
 let () =
   in
   close
 
 (* Main program. *)
 let () =

-  let close = output_to "guestfs-actions.pod" in
-  generate_pod ();
-  close ();
-

   let close = output_to "src/guestfs_protocol.x" in
   generate_xdr ();
   close ();
   let close = output_to "src/guestfs_protocol.x" in
   generate_xdr ();
   close ();

+
+  let close = output_to "src/guestfs-actions.h" in
+  generate_actions_h ();
+  close ();
+
+  let close = output_to "src/guestfs-actions.c" in
+  generate_client_actions ();
+  close ();
+
+  let close = output_to "daemon/actions.h" in
+  generate_daemon_actions_h ();
+  close ();
+
+  let close = output_to "daemon/stubs.c" in
+  generate_daemon_actions ();
+  close ();
+
+  let close = output_to "guestfs-actions.pod" in
+  generate_pod ();
+  close ()