Libguestfs - May 2011 - [PATCH 1/3] hivex: Use OCaml bytecode compiler for caml_raise_with_args check

From: Hilko Bengen <bengen at hilluzination.de>

On installations where no native OCaml compiler is available, the
test program can't be compiled and so we get this message:

,----
| checking for function caml_raise_with_args... not found
`----

This breaks building of the OCaml bindings.

,----
| gcc -std=gnu99 -I.. -I/usr/lib/ocaml -I../ocaml -I../lib   -g -O2 -fPIC -Wall
-c hivex_c.c
| hivex_c.c:52: error: static declaration of 'caml_raise_with_args'
follows non-static declaration
| /usr/lib/ocaml/caml/fail.h:30: note: previous declaration of
'caml_raise_with_args' was here
| make[2]: *** [hivex_c.o] Error 1
`----

(Successfully tested on Debian/unstable on alpha)
---
 configure.ac |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)

diff --git a/configure.ac b/configure.ac
index 5805ddd..ef19543 100644
--- a/configure.ac
+++ b/configure.ac
@@ -192,9 +192,9 @@ if test "x$OCAMLC" != "xno"; then
     echo "char $f (); char foo() { return $f (); }" > conftest.c
     rm -f conftest_ml.ml
     touch conftest_ml.ml
-    if $OCAMLOPT -c conftest.c 2>/dev/null && \
-       $OCAMLOPT -c conftest_ml.ml 2>/dev/null && \
-       $OCAMLOPT conftest.o conftest_ml.cmx -o conftest 2>/dev/null ; then
+    if $OCAMLC -c conftest.c 2>/dev/null && \
+       $OCAMLC -c conftest_ml.ml 2>/dev/null && \
+       $OCAMLC conftest.o conftest_ml.cmo -o conftest 2>/dev/null ; then
         AC_DEFINE([HAVE_CAML_RAISE_WITH_ARGS],[1],
                   [Defined if function caml_raise_with_args exists.])
         AC_MSG_RESULT([found])
-- 
1.7.5.1

From: Hilko Bengen <bengen at hilluzination.de>

Only compile bytecode otherwise, avoiding ocamlfind's helpful error
message "ocamlfind: Not supported in your configuration: ocamlopt"

(Successfully tested on Debian/unstable on alpha)
---
 configure.ac      |    1 +
 ocaml/Makefile.am |    6 +++++-
 2 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/configure.ac b/configure.ac
index ef19543..7e006e8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -174,6 +174,7 @@ dnl Check for OCaml (optional, for OCaml bindings).
 AC_PROG_OCAML
 AC_PROG_FINDLIB
 AM_CONDITIONAL([HAVE_OCAML],[test "x$OCAMLC" != "xno" -a
"x$OCAMLFIND" != "xno"])
+AM_CONDITIONAL([HAVE_OCAMLOPT], [test "x$OCAMLOPT" != "xno"
-a "x$OCAMLFIND" != "xno"])
 
 if test "x$OCAMLC" != "xno"; then
     dnl Check if we have caml/unixsupport.h header (OCaml bindings only).
diff --git a/ocaml/Makefile.am b/ocaml/Makefile.am
index 7412d8d..76c33b9 100644
--- a/ocaml/Makefile.am
+++ b/ocaml/Makefile.am
@@ -31,7 +31,11 @@ AM_CPPFLAGS = \
 
 if HAVE_OCAML
 
-noinst_DATA = mlhivex.cma mlhivex.cmxa META
+noinst_DATA = mlhivex.cma META
+
+if HAVE_OCAMLOPT
+noinst_DATA += mlhivex.cmxa
+endif
 
 OBJS = hivex_c.o hivex.cmo
 XOBJS = $(OBJS:.cmo=.cmx)
-- 
1.7.5.1

From: Hilko Bengen <bengen at hilluzination.de>

* Richard W.M. Jones:
> > Both size_t and int are 32 bit values.  An endianess issue, maybe?
> I guess it might be.  We're supposed to be doing le32toh / be32toh
> everywhere as appropriate, but we might be missing one.  The code is
> mainly tested on little endian arches.
Found it.

Now "make check" completes successfully on Sparc and PowerPC.
---
 lib/hivex.c |    2 +-
 1 files changed, 1 insertions(+), 1 deletions(-)

diff --git a/lib/hivex.c b/lib/hivex.c
index 2abd5bd..7715520 100644
--- a/lib/hivex.c
+++ b/lib/hivex.c
@@ -1062,7 +1062,7 @@ get_values (hive_h *h, hive_node_h node,
 
   size_t i;
   for (i = 0; i < nr_values; ++i) {
-    hive_node_h value = vlist->offset[i];
+    hive_node_h value = le32toh (vlist->offset[i]);
     value += 0x1000;
     if (!IS_VALID_BLOCK (h, value)) {
       if (h->msglvl >= 2)
-- 
1.7.5.1

On Thu, May 12, 2011 at 12:04:18AM +0200, bengen at hilluzination.de
wrote:
> From: Hilko Bengen <bengen at hilluzination.de>
> 
> On installations where no native OCaml compiler is available, the
> test program can't be compiled and so we get this message:
> 
> ,----
> | checking for function caml_raise_with_args... not found
> `----
> 
> This breaks building of the OCaml bindings.
> 
> ,----
> | gcc -std=gnu99 -I.. -I/usr/lib/ocaml -I../ocaml -I../lib   -g -O2 -fPIC
-Wall -c hivex_c.c
> | hivex_c.c:52: error: static declaration of 'caml_raise_with_args'
follows non-static declaration
> | /usr/lib/ocaml/caml/fail.h:30: note: previous declaration of
'caml_raise_with_args' was here
> | make[2]: *** [hivex_c.o] Error 1
> `----
> 
> (Successfully tested on Debian/unstable on alpha)
> ---
>  configure.ac |    6 +++---
>  1 files changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/configure.ac b/configure.ac
> index 5805ddd..ef19543 100644
> --- a/configure.ac
> +++ b/configure.ac
> @@ -192,9 +192,9 @@ if test "x$OCAMLC" != "xno"; then
>      echo "char $f (); char foo() { return $f (); }" >
conftest.c
>      rm -f conftest_ml.ml
>      touch conftest_ml.ml
> -    if $OCAMLOPT -c conftest.c 2>/dev/null && \
> -       $OCAMLOPT -c conftest_ml.ml 2>/dev/null && \
> -       $OCAMLOPT conftest.o conftest_ml.cmx -o conftest 2>/dev/null ;
then
> +    if $OCAMLC -c conftest.c 2>/dev/null && \
> +       $OCAMLC -c conftest_ml.ml 2>/dev/null && \
> +       $OCAMLC conftest.o conftest_ml.cmo -o conftest 2>/dev/null ;
then
>          AC_DEFINE([HAVE_CAML_RAISE_WITH_ARGS],[1],
>                    [Defined if function caml_raise_with_args exists.])
>          AC_MSG_RESULT([found])
> -- 
> 1.7.5.1
> 
> _______________________________________________
> Libguestfs mailing list
> Libguestfs at redhat.com
> https://www.redhat.com/mailman/listinfo/libguestfs
ACK.  I'll push this later today.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
virt-top is 'top' for virtual machines.  Tiny program with many
powerful monitoring features, net stats, disk stats, logging, etc.
http://et.redhat.com/~rjones/virt-top