From 6cbba6117ae103b157c8e1b242de1868117d7601 Mon Sep 17 00:00:00 2001
From: Pino Toscano <ptoscano@redhat.com>
Date: Mon, 24 Aug 2015 17:57:10 +0200
Subject: [PATCH] ocaml: dynamically generate the content of Guestfs.Errno

Put in a list the errnos to expose, filling the content of the
Guestfs.Errno submodule from that.
Also, generate a separate guestfs-c-errnos.c with the implementations of
the functions returning the errno codes.

Only code motion and refactoring, no actual changes on the content of
the ocaml Guestfs module.

(cherry picked from commit 649f439cb78f12bb04ef90d83b81e1fa23495852)
---
 .gitignore         |  1 +
 generator/main.ml  |  1 +
 generator/ocaml.ml | 71 +++++++++++++++++++++++++++++++++++++++++++++++++-----
 ocaml/Makefile.am  |  2 ++
 ocaml/guestfs-c.c  | 16 ------------
 po/POTFILES        |  1 +
 6 files changed, 70 insertions(+), 22 deletions(-)

diff --git a/.gitignore b/.gitignore
index abb63d8..b18a123 100644
--- a/.gitignore
+++ b/.gitignore
@@ -316,6 +316,7 @@ Makefile.in
 /ocaml/examples/inspect_vm
 /ocaml/examples/stamp-guestfs-ocaml.pod
 /ocaml/guestfs-c-actions.c
+/ocaml/guestfs-c-errnos.c
 /ocaml/guestfs.ml
 /ocaml/guestfs.mli
 /ocamlinit-stamp
diff --git a/generator/main.ml b/generator/main.ml
index c0ad146..cb6e77b 100644
--- a/generator/main.ml
+++ b/generator/main.ml
@@ -129,6 +129,7 @@ Run it from the top source directory using the command
   output_to "ocaml/guestfs.mli" generate_ocaml_mli;
   output_to "ocaml/guestfs.ml" generate_ocaml_ml;
   output_to "ocaml/guestfs-c-actions.c" generate_ocaml_c;
+  output_to "ocaml/guestfs-c-errnos.c" generate_ocaml_c_errnos;
   output_to "ocaml/bindtests.ml" generate_ocaml_bindtests;
   output_to "perl/Guestfs.xs" generate_perl_xs;
   output_to "perl/lib/Sys/Guestfs.pm" generate_perl_pm;
diff --git a/generator/ocaml.ml b/generator/ocaml.ml
index a0101d5..f58cab3 100644
--- a/generator/ocaml.ml
+++ b/generator/ocaml.ml
@@ -30,6 +30,14 @@ open Structs
 open C
 open Events
 
+(* List of errnos to expose on Guestfs.Errno. *)
+let ocaml_errnos = [
+  "EINVAL";
+  "ENOTSUP";
+  "EPERM";
+  "ESRCH";
+]
+
 (* Generate the OCaml bindings interface. *)
 let rec generate_ocaml_mli () =
   generate_header OCamlStyle LGPLv2plus;
@@ -132,8 +140,12 @@ val last_errno : t -> int
     which you can use to test the return value of {!Guestfs.last_errno}. *)
 
 module Errno : sig
-  val errno_ENOTSUP : int
-  val errno_ESRCH : int
+";
+  List.iter (
+    fun e ->
+      pr "  val errno_%s : int\n" e
+  ) ocaml_errnos;
+  pr "\
 end
 
 ";
@@ -265,10 +277,15 @@ external event_to_string : event list -> string
 external last_errno : t -> int = \"ocaml_guestfs_last_errno\"
 
 module Errno = struct
-  external enotsup : unit -> int = \"ocaml_guestfs_get_ENOTSUP\" \"noalloc\"
-  let errno_ENOTSUP = enotsup ()
-  external esrch : unit -> int = \"ocaml_guestfs_get_ESRCH\" \"noalloc\"
-  let errno_ESRCH = esrch ()
+";
+  List.iter (
+    fun e ->
+      let le = String.lowercase e in
+      pr "  external %s : unit -> int = \"ocaml_guestfs_get_%s\" \"noalloc\"\n"
+        le e;
+      pr "  let errno_%s = %s ()\n" e le
+  ) ocaml_errnos;
+  pr "\
 end
 
 (* Give the exceptions names, so they can be raised from the C code. *)
@@ -691,6 +708,48 @@ copy_table (char * const * argv)
       )
   ) external_functions_sorted
 
+(* Generate the OCaml bindings C errnos. *)
+and generate_ocaml_c_errnos () =
+  generate_header CStyle LGPLv2plus;
+
+  pr "\
+#include <config.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+
+#include <caml/config.h>
+#include <caml/alloc.h>
+#include <caml/fail.h>
+#include <caml/memory.h>
+#include <caml/mlvalues.h>
+
+#include \"guestfs.h\"
+
+#include \"guestfs-c.h\"
+
+/* These prototypes are solely to quiet gcc warnings. */
+";
+  List.iter (
+    fun e ->
+      pr "value ocaml_guestfs_get_%s (value unitv);\n" e
+  ) ocaml_errnos;
+
+  List.iter (
+    fun e ->
+      pr "\
+
+/* NB: \"noalloc\" function. */
+value
+ocaml_guestfs_get_%s (value unitv)
+{
+  return Val_int (%s);
+}
+" e e
+  ) ocaml_errnos
+
 and generate_ocaml_structure_decls () =
   List.iter (
     fun { s_name = typ; s_cols = cols } ->
diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
index 94f11ef..d2444dc 100644
--- a/ocaml/Makefile.am
+++ b/ocaml/Makefile.am
@@ -21,6 +21,7 @@ generator_built = \
 	guestfs.mli \
 	guestfs.ml \
 	guestfs-c-actions.c \
+	guestfs-c-errnos.c \
 	$(srcdir)/bindtests.ml
 
 EXTRA_DIST = \
@@ -87,6 +88,7 @@ libguestfsocaml_a_CFLAGS = \
 libguestfsocaml_a_SOURCES = \
 	guestfs-c.c \
 	guestfs-c-actions.c \
+	guestfs-c-errnos.c \
 	../src/utils.c
 
 if HAVE_OCAMLDOC
diff --git a/ocaml/guestfs-c.c b/ocaml/guestfs-c.c
index 0ebb84c..1bcf5b8 100644
--- a/ocaml/guestfs-c.c
+++ b/ocaml/guestfs-c.c
@@ -63,8 +63,6 @@ value ocaml_guestfs_set_event_callback (value gv, value closure, value events);
 value ocaml_guestfs_delete_event_callback (value gv, value eh);
 value ocaml_guestfs_event_to_string (value events);
 value ocaml_guestfs_last_errno (value gv);
-value ocaml_guestfs_get_ENOTSUP (value unitv);
-value ocaml_guestfs_get_ESRCH (value unitv);
 
 /* Allocate handles and deal with finalization. */
 static void
@@ -440,17 +438,3 @@ ocaml_guestfs_last_errno (value gv)
   rv = Val_int (r);
   CAMLreturn (rv);
 }
-
-/* NB: "noalloc" function. */
-value
-ocaml_guestfs_get_ENOTSUP (value unitv)
-{
-  return Val_int (ENOTSUP);
-}
-
-/* NB: "noalloc" function. */
-value
-ocaml_guestfs_get_ESRCH (value unitv)
-{
-  return Val_int (ESRCH);
-}
diff --git a/po/POTFILES b/po/POTFILES
index 7c99fd0..b359bf6 100644
--- a/po/POTFILES
+++ b/po/POTFILES
@@ -252,6 +252,7 @@ mllib/progress-c.c
 mllib/tty-c.c
 mllib/uri-c.c
 ocaml/guestfs-c-actions.c
+ocaml/guestfs-c-errnos.c
 ocaml/guestfs-c.c
 p2v/authors.c
 p2v/config.c
-- 
1.8.3.1