Hi, how can I compile udev with cross compilation?

DISCUSSION huyle 3 participants 5 messages Feb 20, 2010

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huyle

author

2010-02-20 09:52 UTC #0 lore raw

Hi,
I am currently building an linux system for arm board. I am stuck with udev. So can you help me with some commands to compile udev with cross compilation?
Thanks for your time
---------------------------
Huy

Paul Bender

2010-02-20 16:37 UTC #1 lore raw

Quoted 5 lines · huyle

Hi,
I am currently building an linux system for arm board. I am stuck with udev. So can you help me with some commands to compile udev with cross compilation?
Thanks for your time

I am cross compiling udev, but not for the ARM.

The only trouble that I have encountered when cross compiling version 151 is with the configure scripts determination of the pci.ids file location. This is caused by autoconf's AC_CHECK_FILES macro generating an error when cross compiling. However, this can be worked around by setting

ac_cv_file__usr_share_pci_ids='no'
ac_cv_file__usr_share_hwdata_pci_ids='no'
ac_cv_file__usr_share_misc_pci_ids='no'

in the build system's environment before running configure and setting the configure script's --with-pci-ids-path argument.

I have had this work around for so long that I have not given it much thought. However, it is relatively easy to fix the configure script so that it only attempting to determine the pci.ids file location when --with-pci-ids-path is not set. Therefore, I have created and attached a patch that should do this. Of course, after applying, you would need to rerun autoconf or autoreconf.

configure.ac +4 -6

diff -Naur udev-151-old/configure.ac udev-151-new/configure.ac
@@ -69,15 +69,13 @@
 	PKG_CHECK_MODULES(USBUTILS, usbutils >= 0.82)
 	AC_SUBST([USB_DATABASE], [$($PKG_CONFIG --variable=usbids usbutils)])
 
-	AC_CHECK_FILES([/usr/share/pci.ids], [pciids=/usr/share/pci.ids])
-	AC_CHECK_FILES([/usr/share/hwdata/pci.ids], [pciids=/usr/share/hwdata/pci.ids])
-	AC_CHECK_FILES([/usr/share/misc/pci.ids], [pciids=/usr/share/misc/pci.ids])
 	AC_ARG_WITH(pci-ids-path,
 		AS_HELP_STRING([--pci-ids-path=DIR], [Path to pci.ids file]),
 		[PCI_DATABASE=${withval}],
-		[if test -n "$pciids" ; then
-			PCI_DATABASE="$pciids"
-		else
+		[AC_CHECK_FILES([/usr/share/pci.ids], [PCI_DATABASE=/usr/share/pci.ids])
+		AC_CHECK_FILES([/usr/share/hwdata/pci.ids], [PCI_DATABASE=/usr/share/hwdata/pci.ids])
+		AC_CHECK_FILES([/usr/share/misc/pci.ids], [PCI_DATABASE=/usr/share/misc/pci.ids])
+		if test -x "$PCI_DATABASE" ; then
 			AC_MSG_ERROR([pci.ids not found, try --with-pci-ids-path=])
 		fi])
 	AC_SUBST(PCI_DATABASE)

Dan Nicholson

2010-02-20 18:20 UTC #2 lore raw

In reply to huyle

Quoted 22 lines · Paul Bender

Quoted 6 lines · huyle
Hi,
I am currently building an linux system for arm board. I am stuck with udev. So can you help me with some commands to compile udev with cross compilation?
Thanks for your time
I am cross compiling udev, but not for the ARM.
The only trouble that I have encountered when cross compiling version 151 is with the configure scripts determination of the pci.ids file location. This is caused by autoconf's AC_CHECK_FILES macro generating an error when cross compiling. However, this can be worked around by setting
ac_cv_file__usr_share_pci_ids='no'
ac_cv_file__usr_share_hwdata_pci_ids='no'
ac_cv_file__usr_share_misc_pci_ids='no'
in the build system's environment before running configure and setting the configure script's --with-pci-ids-path argument.

Quoted 6 lines

I have had this work around for so long that I have not given it much thought. However, it is relatively easy to fix the configure script so that it only attempting to determine the pci.ids file location when --with-pci-ids-path is not set. Therefore, I have created and attached a patch that should do this. Of course, after applying, you would need to rerun autoconf or autoreconf.

I think it would be better to just make the AC_CHECK_FILES conditional on cross compiling:

if test $cross_compiling != yes; then

    AC_CHECK_FILES...
else
    # just assume pciids location
    pciids=/usr/share/pci.ids
fi

Otherwise, people cross compiling will bomb unless they pass --with-pci-ids-path. Likewise, you changed the 'test -n "$pciids"' to a 'test -x'. I don't know a lot of people with an executable pci database. Attached is a patch to do this.

--
Dan

From 779098c43b0c2f3b88dedea77dfc2e891fe39c26 Mon Sep 17 00:00:00 2001
From: Dan Nicholson <[email protected]>
Date: Sat, 20 Feb 2010 09:20:20 -0800
Subject: [PATCH] pci.ids: Fix PCI database checking for cross compiling

When cross compiling, AC_CHECK_FILES will error, so a default location is assumed in this case. A message is added to the end of the check to let the user know what udev has decided.

Signed-off-by Dan Nicholson <[email protected]>

---
 configure.ac |   18 ++++++++++++++----
 1 files changed, 14 insertions(+), 4 deletions(-)

configure.ac +14 -4

index 88824b6..2d000cf 100644
@@ -69,17 +69,27 @@ if test "x$enable_extras" = xyes; then
 	PKG_CHECK_MODULES(USBUTILS, usbutils >= 0.82)
 	AC_SUBST([USB_DATABASE], [$($PKG_CONFIG --variable=usbids usbutils)])
 
-	AC_CHECK_FILES([/usr/share/pci.ids], [pciids=/usr/share/pci.ids])
-	AC_CHECK_FILES([/usr/share/hwdata/pci.ids], [pciids=/usr/share/hwdata/pci.ids])
-	AC_CHECK_FILES([/usr/share/misc/pci.ids], [pciids=/usr/share/misc/pci.ids])
+	if test $cross_compiling = no; then
+		AC_CHECK_FILES([/usr/share/pci.ids],
+			       [pciids=/usr/share/pci.ids])
+		AC_CHECK_FILES([/usr/share/hwdata/pci.ids],
+			       [pciids=/usr/share/hwdata/pci.ids])
+		AC_CHECK_FILES([/usr/share/misc/pci.ids],
+			       [pciids=/usr/share/misc/pci.ids])
+	else
+		# just assume location
+		pciids=/usr/share/pci.ids
+	fi
 	AC_ARG_WITH(pci-ids-path,
-		AS_HELP_STRING([--pci-ids-path=DIR], [Path to pci.ids file]),
+		[AS_HELP_STRING([--with-pci-ids-path=DIR], [Path to pci.ids file])],
 		[PCI_DATABASE=${withval}],
 		[if test -n "$pciids" ; then
 			PCI_DATABASE="$pciids"
 		else
 			AC_MSG_ERROR([pci.ids not found, try --with-pci-ids-path=])
 		fi])
+	AC_MSG_CHECKING([for PCI database location])
+	AC_MSG_RESULT([$PCI_DATABASE])
 	AC_SUBST(PCI_DATABASE)
 
 	AC_CHECK_HEADER([linux/input.h], [:], AC_MSG_ERROR([kernel headers not found]))

Signature · 1 line

1.6.6

Paul Bender

2010-02-20 19:15 UTC #3 lore raw

In reply to huyle

Quoted 34 lines · Dan Nicholson

Quoted 22 lines · Paul Bender
Quoted 6 lines · huyle
Hi,
I am currently building an linux system for arm board. I am stuck with udev. So can you help me with some commands to compile udev with cross compilation?
Thanks for your time
I am cross compiling udev, but not for the ARM.
The only trouble that I have encountered when cross compiling version 151 is with the configure scripts determination of the pci.ids file location. This is caused by autoconf's AC_CHECK_FILES macro generating an error when cross compiling. However, this can be worked around by setting
ac_cv_file__usr_share_pci_ids='no'
ac_cv_file__usr_share_hwdata_pci_ids='no'
ac_cv_file__usr_share_misc_pci_ids='no'
in the build system's environment before running configure and setting the configure script's --with-pci-ids-path argument.
Quoted 6 lines
I have had this work around for so long that I have not given it much thought. However, it is relatively easy to fix the configure script so that it only attempting to determine the pci.ids file location when --with-pci-ids-path is not set. Therefore, I have created and attached a patch that should do this. Of course, after applying, you would need to rerun autoconf or autoreconf.
I think it would be better to just make the AC_CHECK_FILES conditional on cross compiling:
if test $cross_compiling != yes; then

Quoted 8 lines

     AC_CHECK_FILES...pci.ids not found, try --with-pci-ids-path
else
     # just assume pciids location
     pciids=/usr/share/pci.ids
fi
Otherwise, people cross compiling will bomb unless they pass --with-pci-ids-path.

Unless I misunderstand AC_ARG_WITH, its third argument is for what to do when the corresponding --with configure argument is not provided, which is how it behaves in my build system (with autoconf 2.63). That is why I put the AC_CHECK_FILES in the third argument.

I like your patch better than mine as it does not generate the unhelpful error message:
"cannot check for file existence when cross compiling".
when the --with-pci-ids-path is not provided.

However, for cross compiling, it might be better to force the user to provide --with-pci-ids-path rather than assuming one since an incorrect assumed path would not be discovered until on target runtime.

Quoted 3 lines

Likewise, you changed the 'test -n "$pciids"' to
a 'test -x'. I don't know a lot of people with an executable pci database. Attached is a patch to do this.

Doh, that was supposed to be -z. Thanks for the catch.

Dan Nicholson

2010-02-20 19:26 UTC #4 lore raw

In reply to huyle

Quoted 56 lines · Paul Bender

Quoted 43 lines · Dan Nicholson
Quoted 27 lines · Paul Bender
Quoted 6 lines · huyle
Hi,
I am currently building an linux system for arm board. I am stuck with udev. So can you help me with some commands to compile udev with cross compilation?
Thanks for your time
I am cross compiling udev, but not for the ARM.
The only trouble that I have encountered when cross compiling version 151 is
with the configure scripts determination of the pci.ids file location. This
is caused by autoconf's AC_CHECK_FILES macro generating an error when cross
compiling. However, this can be worked around by setting
ac_cv_file__usr_share_pci_ids='no'
ac_cv_file__usr_share_hwdata_pci_ids='no'
ac_cv_file__usr_share_misc_pci_ids='no'
in the build system's environment before running configure and setting the
configure script's --with-pci-ids-path argument.
Quoted 7 lines
I have had this work around for so long that I have not given it much thought. However, it is relatively easy to fix the configure script so that
it only attempting to determine the pci.ids file location when --with-pci-ids-path is not set. Therefore, I have created and attached a patch that should do this. Of course, after applying, you would need to rerun autoconf or autoreconf.
I think it would be better to just make the AC_CHECK_FILES conditional on cross compiling:
if test $cross_compiling != yes; then AC_CHECK_FILES...pci.ids not found, try --with-pci-ids-path else
Quoted 6 lines
    # just assume pciids location
    pciids=/usr/share/pci.ids
fi
Otherwise, people cross compiling will bomb unless they pass --with-pci-ids-path.
Unless I misunderstand AC_ARG_WITH, its third argument is for what to do when the corresponding --with configure argument is not provided, which is how it behaves in my build system (with autoconf 2.63). That is why I put the AC_CHECK_FILES in the third argument.

Quoted 8 lines

I like your patch better than mine as it does not generate the unhelpful error message:
"cannot check for file existence when cross compiling".
when the --with-pci-ids-path is not provided.
However, for cross compiling, it might be better to force the user to provide --with-pci-ids-path rather than assuming one since an incorrect assumed path would not be discovered until on target runtime.

Yeah, there's definitely a balance there. That's why I added the message so people would at least see what udev was going to use. I just prefer the "don't make people pass options to configure unless they definitely have to" approach. Could easily go both ways, though.

Quoted 5 lines

Quoted 3 lines
Likewise, you changed the 'test -n "$pciids"' to
a 'test -x'. I don't know a lot of people with an executable pci database. Attached is a patch to do this.
Doh, that was supposed to be -z. Thanks for the catch.

With that fix I think either patch would be fine.

--
Dan