[PATCH 0 of 4 v2] build: various fixes for building with uclibc and libiconv

[PATCH 0 of 4 v2] build: various fixes for building with uclibc and libiconv

[Roger Pau Monne]

This patch contains various fixes to the build system to allow
building xen under uclibc with libiconv. Has been tested with uclibc
0.9.32, gcc 4.6.2 and libiconv 1.12, from Alpine Linux 2.3.2.

Since the series is completely different from the previous one, I
don't think it's worth to add a "Changes since v1" section, becasue
everything is different.

Please review, Roger.

[PATCH 1 of 4 v2] blktap: remove local definitions and include byteswap.h

[Roger Pau Monne]

# HG changeset patch
# User Roger Pau Monne <roger.pau@entel.upc.edu>
# Date 1324344433 -3600
# Node ID 29f5b0afe971335eea4f547efed00b132ade5c64
# Parent  d23344a87ad7d3d3acae83171586358b081e3f4e
blktap: remove local definitions and include byteswap.h

Use the same approach as tools/blktap2/include/libvhd.h, remove local
definitions of bswap* and include byteswap.h. Also remove the
HAVE_BYTESWAP_H ifdef, since it was not defined in this context (it's
defined by QEMU).

Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>

diff -r d23344a87ad7 -r 29f5b0afe971 tools/blktap/drivers/bswap.h
--- a/tools/blktap/drivers/bswap.h	Tue Dec 20 02:21:25 2011 +0100
+++ b/tools/blktap/drivers/bswap.h	Tue Dec 20 02:27:13 2011 +0100
@@ -15,43 +15,7 @@
 #define bswap_64(x) swap64(x)
 #else
 
-#ifdef HAVE_BYTESWAP_H
 #include <byteswap.h>
-#else
-
-#define bswap_16(x) \
-({ \
-	uint16_t __x = (x); \
-	((uint16_t)( \
-		(((uint16_t)(__x) & (uint16_t)0x00ffU) << 8) | \
-		(((uint16_t)(__x) & (uint16_t)0xff00U) >> 8) )); \
-})
-
-#define bswap_32(x) \
-({ \
-	uint32_t __x = (x); \
-	((uint32_t)( \
-		(((uint32_t)(__x) & (uint32_t)0x000000ffUL) << 24) | \
-		(((uint32_t)(__x) & (uint32_t)0x0000ff00UL) <<  8) | \
-		(((uint32_t)(__x) & (uint32_t)0x00ff0000UL) >>  8) | \
-		(((uint32_t)(__x) & (uint32_t)0xff000000UL) >> 24) )); \
-})
-
-#define bswap_64(x) \
-({ \
-	uint64_t __x = (x); \
-	((uint64_t)( \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000000000ffULL) << 56) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000ff000000ULL) <<  8) | \
-	        (uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000ff00000000ULL) >>  8) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0xff00000000000000ULL) >> 56) )); \
-})
-
-#endif /* !HAVE_BYTESWAP_H */
 
 static inline uint16_t bswap16(uint16_t x)
 {

[PATCH 2 of 4 v2] blktap2: remove local definitions and include byteswap.h

[Roger Pau Monne]

# HG changeset patch
# User Roger Pau Monne <roger.pau@entel.upc.edu>
# Date 1324344514 -3600
# Node ID 23e1abbd203ca2619103f3e95c6b1ff36be60e38
# Parent  29f5b0afe971335eea4f547efed00b132ade5c64
blktap2: remove local definitions and include byteswap.h

Use the same approach as tools/blktap2/include/libvhd.h, remove local
definitions of bswap* and include byteswap.h. Also remove the
HAVE_BYTESWAP_H ifdef, since it was not defined in this context (it's
defined by QEMU).

Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>

diff -r 29f5b0afe971 -r 23e1abbd203c tools/blktap2/drivers/bswap.h
--- a/tools/blktap2/drivers/bswap.h	Tue Dec 20 02:27:13 2011 +0100
+++ b/tools/blktap2/drivers/bswap.h	Tue Dec 20 02:28:34 2011 +0100
@@ -15,43 +15,8 @@
 #define bswap_64(x) swap64(x)
 #else
 
-#ifdef HAVE_BYTESWAP_H
+#include <endian.h>
 #include <byteswap.h>
-#else
-
-#define bswap_16(x) \
-({ \
-	uint16_t __x = (x); \
-	((uint16_t)( \
-		(((uint16_t)(__x) & (uint16_t)0x00ffU) << 8) | \
-		(((uint16_t)(__x) & (uint16_t)0xff00U) >> 8) )); \
-})
-
-#define bswap_32(x) \
-({ \
-	uint32_t __x = (x); \
-	((uint32_t)( \
-		(((uint32_t)(__x) & (uint32_t)0x000000ffUL) << 24) | \
-		(((uint32_t)(__x) & (uint32_t)0x0000ff00UL) <<  8) | \
-		(((uint32_t)(__x) & (uint32_t)0x00ff0000UL) >>  8) | \
-		(((uint32_t)(__x) & (uint32_t)0xff000000UL) >> 24) )); \
-})
-
-#define bswap_64(x) \
-({ \
-	uint64_t __x = (x); \
-	((uint64_t)( \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000000000ffULL) << 56) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000ff000000ULL) <<  8) | \
-	        (uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000ff00000000ULL) >>  8) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
-		(uint64_t)(((uint64_t)(__x) & (uint64_t)0xff00000000000000ULL) >> 56) )); \
-})
-
-#endif /* !HAVE_BYTESWAP_H */
 
 static inline uint16_t bswap16(uint16_t x)
 {

[PATCH 3 of 4 v2] build: detect is libiconv is present

[Roger Pau Monne]

# HG changeset patch
# User Roger Pau Monne <roger.pau@entel.upc.edu>
# Date 1324344612 -3600
# Node ID 14e911353a91702b439bc06e2a77d67e8bd5f661
# Parent  23e1abbd203ca2619103f3e95c6b1ff36be60e38
build: detect is libiconv is present

Detect if libiconv is present in the system, since we will have to
link against it when using iconv.

Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>

diff -r 23e1abbd203c -r 14e911353a91 Config.mk
--- a/Config.mk	Tue Dec 20 02:28:34 2011 +0100
+++ b/Config.mk	Tue Dec 20 02:30:12 2011 +0100
@@ -18,6 +18,8 @@ XEN_TARGET_ARCH     ?= $(XEN_COMPILE_ARC
 XEN_OS              ?= $(shell uname -s)
 
 CONFIG_$(XEN_OS) := y
+CONFIG_LIBICONV  := $(shell grep -q LIBICONV_PLUG /usr/include/iconv.h \
+                      && echo 'y' || echo 'n')
 
 SHELL     ?= /bin/sh

[PATCH 4 of 4 v2] blktap2/vhd: add -liconv when linking if using libiconv

[Roger Pau Monne]

# HG changeset patch
# User Roger Pau Monne <roger.pau@entel.upc.edu>
# Date 1324344791 -3600
# Node ID 993c86e4ecbc85a95f27ba299e8e9285d76c56b2
# Parent  14e911353a91702b439bc06e2a77d67e8bd5f661
blktap2/vhd: add -liconv when linking if using libiconv

If libiconv is detected on the system add -liconv when linking the
libvhd library.

If -liconv is not added when compiling libvhd with libiconv the
following error occours when linking vhd-util and vhd-update:

gcc     -o vhd-util vhd-util.o -Llib -lvhd
lib/libvhd.so: undefined reference to `libiconv_open'
lib/libvhd.so: undefined reference to `libiconv_close'
lib/libvhd.so: undefined reference to `libiconv'

Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>

diff -r 14e911353a91 -r 993c86e4ecbc tools/blktap2/vhd/lib/Makefile
--- a/tools/blktap2/vhd/lib/Makefile	Tue Dec 20 02:30:12 2011 +0100
+++ b/tools/blktap2/vhd/lib/Makefile	Tue Dec 20 02:33:11 2011 +0100
@@ -23,6 +23,10 @@ ifeq ($(CONFIG_Linux),y)
 LIBS            := -luuid
 endif
 
+ifeq ($(CONFIG_LIBICONV),y)
+LIBS            += -liconv
+endif
+
 LIB-SRCS        := libvhd.c
 LIB-SRCS        += libvhd-journal.c
 LIB-SRCS        += vhd-util-coalesce.c

Re: [PATCH 3 of 4 v2] build: detect is libiconv is present

[William Pitcock]

Hi,

On Mon, Dec 19, 2011 at 8:19 PM, Roger Pau Monne
<roger.pau@entel.upc.edu> wrote:
> # HG changeset patch
> # User Roger Pau Monne <roger.pau@entel.upc.edu>
> # Date 1324344612 -3600
> # Node ID 14e911353a91702b439bc06e2a77d67e8bd5f661
> # Parent  23e1abbd203ca2619103f3e95c6b1ff36be60e38
> build: detect is libiconv is present
>
> Detect if libiconv is present in the system, since we will have to
> link against it when using iconv.
>
> Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
>
> diff -r 23e1abbd203c -r 14e911353a91 Config.mk
> --- a/Config.mk Tue Dec 20 02:28:34 2011 +0100
> +++ b/Config.mk Tue Dec 20 02:30:12 2011 +0100
> @@ -18,6 +18,8 @@ XEN_TARGET_ARCH     ?= $(XEN_COMPILE_ARC
>  XEN_OS              ?= $(shell uname -s)
>
>  CONFIG_$(XEN_OS) := y
> +CONFIG_LIBICONV  := $(shell grep -q LIBICONV_PLUG /usr/include/iconv.h \
> +                      && echo 'y' || echo 'n')
>

Please don't check this way, it is not guaranteed to work.  Check
instead for presence of libiconv.so somehow, perhaps using a dummy
program with -liconv or something, or using a construct like:

  test -f /usr/lib/libiconv.so -o -f /lib/libiconv.so -o -f
/usr/local/lib/libiconv.so && echo 'y' || echo 'n'

If upstream removes LIBICONV_PLUG, this check will break.

Otherwise, everything else looks OK to me.

William

Re: [PATCH 3 of 4 v2] build: detect is libiconv is present

[Jean Guyader]

On 21 December 2011 12:00, William Pitcock <nenolod@dereferenced.org> wrote:
> Hi,
>
> On Mon, Dec 19, 2011 at 8:19 PM, Roger Pau Monne
> <roger.pau@entel.upc.edu> wrote:
>> # HG changeset patch
>> # User Roger Pau Monne <roger.pau@entel.upc.edu>
>> # Date 1324344612 -3600
>> # Node ID 14e911353a91702b439bc06e2a77d67e8bd5f661
>> # Parent  23e1abbd203ca2619103f3e95c6b1ff36be60e38
>> build: detect is libiconv is present
>>
>> Detect if libiconv is present in the system, since we will have to
>> link against it when using iconv.
>>
>> Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
>>
>> diff -r 23e1abbd203c -r 14e911353a91 Config.mk
>> --- a/Config.mk Tue Dec 20 02:28:34 2011 +0100
>> +++ b/Config.mk Tue Dec 20 02:30:12 2011 +0100
>> @@ -18,6 +18,8 @@ XEN_TARGET_ARCH     ?= $(XEN_COMPILE_ARC
>>  XEN_OS              ?= $(shell uname -s)
>>
>>  CONFIG_$(XEN_OS) := y
>> +CONFIG_LIBICONV  := $(shell grep -q LIBICONV_PLUG /usr/include/iconv.h \
>> +                      && echo 'y' || echo 'n')
>>
>
> Please don't check this way, it is not guaranteed to work.  Check
> instead for presence of libiconv.so somehow, perhaps using a dummy
> program with -liconv or something, or using a construct like:
>
>  test -f /usr/lib/libiconv.so -o -f /lib/libiconv.so -o -f
> /usr/local/lib/libiconv.so && echo 'y' || echo 'n'
>
> If upstream removes LIBICONV_PLUG, this check will break.
>
> Otherwise, everything else looks OK to me.
>

That doesn't work if you do cross compilation, your libraries could
located in a completely different path.

The best way to check for the presence of a library (and this is how
the autotools do it) is to generate a very simple C program that uses
some iconv functions and try to compile it with the currently
configured compiler. If the compilation succeeded that means the
library is present.

Jean

Re: [PATCH 1 of 4 v2] blktap: remove local definitions and include byteswap.h

[Ian Campbell]

On Tue, 2011-12-20 at 02:19 +0000, Roger Pau Monne wrote:
> # HG changeset patch
> # User Roger Pau Monne <roger.pau@entel.upc.edu>
> # Date 1324344433 -3600
> # Node ID 29f5b0afe971335eea4f547efed00b132ade5c64
> # Parent  d23344a87ad7d3d3acae83171586358b081e3f4e
> blktap: remove local definitions and include byteswap.h
> 
> Use the same approach as tools/blktap2/include/libvhd.h, remove local
> definitions of bswap* and include byteswap.h.

The end result of this patch isn't quite the same as libvhd.h. There it
does:

        #if defined(__linux__)
        #include <endian.h>
        #include <byteswap.h>
        #elif defined(__NetBSD__)
        #include <sys/endian.h>
        #include <sys/bswap.h>
        #endif

while here we end up with:

        #if defined(__NetBSD__)
        #include <sys/endian.h>
        #include <sys/types.h>
        #elif defined(__OpenBSD__)
        #include <machine/endian.h>
        #define bswap_16(x) swap16(x)
        #define bswap_32(x) swap32(x)
        #define bswap_64(x) swap64(x)
        #else
        #include <byteswap.h>
        #endif
        
I think that last #else should be an explicit #elif defined(__linux__)
for consistency and so that future porters don't wander around looking
for byteswap.h before realising they need a new #elif clause.

>  Also remove the
> HAVE_BYTESWAP_H ifdef, since it was not defined in this context (it's
> defined by QEMU).
> 
> Signed-off-by: Roger Pau Monne <roger.pau@entel.upc.edu>
> 
> diff -r d23344a87ad7 -r 29f5b0afe971 tools/blktap/drivers/bswap.h
> --- a/tools/blktap/drivers/bswap.h	Tue Dec 20 02:21:25 2011 +0100
> +++ b/tools/blktap/drivers/bswap.h	Tue Dec 20 02:27:13 2011 +0100
> @@ -15,43 +15,7 @@
>  #define bswap_64(x) swap64(x)
>  #else
>  
> -#ifdef HAVE_BYTESWAP_H
>  #include <byteswap.h>
> -#else
> -
> -#define bswap_16(x) \
> -({ \
> -	uint16_t __x = (x); \
> -	((uint16_t)( \
> -		(((uint16_t)(__x) & (uint16_t)0x00ffU) << 8) | \
> -		(((uint16_t)(__x) & (uint16_t)0xff00U) >> 8) )); \
> -})
> -
> -#define bswap_32(x) \
> -({ \
> -	uint32_t __x = (x); \
> -	((uint32_t)( \
> -		(((uint32_t)(__x) & (uint32_t)0x000000ffUL) << 24) | \
> -		(((uint32_t)(__x) & (uint32_t)0x0000ff00UL) <<  8) | \
> -		(((uint32_t)(__x) & (uint32_t)0x00ff0000UL) >>  8) | \
> -		(((uint32_t)(__x) & (uint32_t)0xff000000UL) >> 24) )); \
> -})
> -
> -#define bswap_64(x) \
> -({ \
> -	uint64_t __x = (x); \
> -	((uint64_t)( \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000000000ffULL) << 56) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000000000ff00ULL) << 40) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000000000ff0000ULL) << 24) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00000000ff000000ULL) <<  8) | \
> -	        (uint64_t)(((uint64_t)(__x) & (uint64_t)0x000000ff00000000ULL) >>  8) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x0000ff0000000000ULL) >> 24) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0x00ff000000000000ULL) >> 40) | \
> -		(uint64_t)(((uint64_t)(__x) & (uint64_t)0xff00000000000000ULL) >> 56) )); \
> -})
> -
> -#endif /* !HAVE_BYTESWAP_H */
>  
>  static inline uint16_t bswap16(uint16_t x)
>  {
> 
> _______________________________________________
> Xen-devel mailing list
> Xen-devel@lists.xensource.com
> http://lists.xensource.com/xen-devel

Re: [PATCH 3 of 4 v2] build: detect is libiconv is present

[Roger Pau Monné]

2011/12/21 Jean Guyader <jean.guyader@gmail.com>:
> That doesn't work if you do cross compilation, your libraries could
> located in a completely different path.
>
> The best way to check for the presence of a library (and this is how
> the autotools do it) is to generate a very simple C program that uses
> some iconv functions and try to compile it with the currently
> configured compiler. If the compilation succeeded that means the
> library is present.

I'm not sure this is easy to implement without much fuss, given the
way Xen checks for configuration options. What about this:

CONFIG_LIBICONV   := $(shell export OS="`uname -s`"; \
                       export CHECK_LIB="$(CHECK_LIB)"; \
                       . $(XEN_ROOT)/tools/check/funcs.sh; \
                       has_lib libiconv.so && echo 'y' || echo 'n')

Re: [PATCH 3 of 4 v2] build: detect is libiconv is present

[Jean Guyader]

On 21 December 2011 15:56, Roger Pau Monné <roger.pau@entel.upc.edu> wrote:
> 2011/12/21 Jean Guyader <jean.guyader@gmail.com>:
>> That doesn't work if you do cross compilation, your libraries could
>> located in a completely different path.
>>
>> The best way to check for the presence of a library (and this is how
>> the autotools do it) is to generate a very simple C program that uses
>> some iconv functions and try to compile it with the currently
>> configured compiler. If the compilation succeeded that means the
>> library is present.
>
> I'm not sure this is easy to implement without much fuss, given the
> way Xen checks for configuration options. What about this:
>
> CONFIG_LIBICONV   := $(shell export OS="`uname -s`"; \
>                       export CHECK_LIB="$(CHECK_LIB)"; \
>                       . $(XEN_ROOT)/tools/check/funcs.sh; \
>                       has_lib libiconv.so && echo 'y' || echo 'n')

I think that does the right thing.

Jean