[FFmpeg-devel] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing

Submitted by Aaron Levinson on April 14, 2017, 12:56 a.m.

Details

Message ID 2e3d0aae-32c0-ffc1-d1f5-f76884ab67b2@aracnet.com
State New
Headers show

Commit Message

Aaron Levinson April 14, 2017, 12:56 a.m.
From 48f7daba16e0fcdb83d9abd254800c7b9f4ab684 Mon Sep 17 00:00:00 2001
From: Aaron Levinson <alevinsn@aracnet.com>
Date: Thu, 13 Apr 2017 17:30:47 -0700
Subject: [PATCH] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing

Purpose: Enhanced require_pkg_config() in configure to
fallback to require() if pkg-config is missing

Notes: This is likely mainly of relevance when building with MSVC on
Windows.  In my case, I used this approach to get libmfx when invoking
configure with --enable-libmfx, which is used for QuickSync (QSV).

Comments:

-- configure: Enhanced require_pkg_config() function to first check if
   $pkg_config is not false.  If not false, it goes through the
   standard steps of calling use_pkg_config(), but if false, it issues
   a log message and then calls require() with all the inputted
   arguments and an additional argument: -l$1.  So, for something like
   "require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit", this becomes
   "require libmfx "mfx/mfxvideo.h" MFXInit -llibmfx".  This is not a
   perfect solution, but the previous approach didn't work at all
   before when require_pkg_config() is used.
---
 configure | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

Comments

Hendrik Leppkes April 14, 2017, 8:09 a.m.
On Fri, Apr 14, 2017 at 2:56 AM, Aaron Levinson <alevinsn@aracnet.com> wrote:
> From 48f7daba16e0fcdb83d9abd254800c7b9f4ab684 Mon Sep 17 00:00:00 2001
> From: Aaron Levinson <alevinsn@aracnet.com>
> Date: Thu, 13 Apr 2017 17:30:47 -0700
> Subject: [PATCH] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing
>
> Purpose: Enhanced require_pkg_config() in configure to
> fallback to require() if pkg-config is missing
>
> Notes: This is likely mainly of relevance when building with MSVC on
> Windows.  In my case, I used this approach to get libmfx when invoking
> configure with --enable-libmfx, which is used for QuickSync (QSV).
>
> Comments:
>
> -- configure: Enhanced require_pkg_config() function to first check if
>    $pkg_config is not false.  If not false, it goes through the
>    standard steps of calling use_pkg_config(), but if false, it issues
>    a log message and then calls require() with all the inputted
>    arguments and an additional argument: -l$1.  So, for something like
>    "require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit", this becomes
>    "require libmfx "mfx/mfxvideo.h" MFXInit -llibmfx".  This is not a
>    perfect solution, but the previous approach didn't work at all
>    before when require_pkg_config() is used.
> ---
>  configure | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
>
> diff --git a/configure b/configure
> index 7f2b653..ad08b82 100755
> --- a/configure
> +++ b/configure
> @@ -1347,7 +1347,12 @@ use_pkg_config(){
>  }
>
>  require_pkg_config(){
> -    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
> +    if test $pkg_config != false; then
> +        use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
> +    else
> +        log require_pkg_config "No pkg-config, using require for $@"
> +        require "$@ -l$1"
> +    fi
>  }
>

pkg-config typically provides more then just a location of the files,
and while it happens to work for mfx in your case, I don't think this
generic fallback is a good idea.
We already require a linux-esque build environment, even for MSVC
builds (ie. msys or cygwin, etc), having pkg-config on top of the
other required tools isn't that hard of a dependency to fullfill - I
do that all the time.

- Hendrik
Aaron Levinson April 15, 2017, 12:03 a.m.
On 4/14/2017 1:09 AM, Hendrik Leppkes wrote:
> On Fri, Apr 14, 2017 at 2:56 AM, Aaron Levinson <alevinsn@aracnet.com> wrote:
>> From 48f7daba16e0fcdb83d9abd254800c7b9f4ab684 Mon Sep 17 00:00:00 2001
>> From: Aaron Levinson <alevinsn@aracnet.com>
>> Date: Thu, 13 Apr 2017 17:30:47 -0700
>> Subject: [PATCH] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing
>>
>> Purpose: Enhanced require_pkg_config() in configure to
>> fallback to require() if pkg-config is missing
>>
>> Notes: This is likely mainly of relevance when building with MSVC on
>> Windows.  In my case, I used this approach to get libmfx when invoking
>> configure with --enable-libmfx, which is used for QuickSync (QSV).
>>
>> Comments:
>>
>> -- configure: Enhanced require_pkg_config() function to first check if
>>    $pkg_config is not false.  If not false, it goes through the
>>    standard steps of calling use_pkg_config(), but if false, it issues
>>    a log message and then calls require() with all the inputted
>>    arguments and an additional argument: -l$1.  So, for something like
>>    "require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit", this becomes
>>    "require libmfx "mfx/mfxvideo.h" MFXInit -llibmfx".  This is not a
>>    perfect solution, but the previous approach didn't work at all
>>    before when require_pkg_config() is used.
>> ---
>>  configure | 7 ++++++-
>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/configure b/configure
>> index 7f2b653..ad08b82 100755
>> --- a/configure
>> +++ b/configure
>> @@ -1347,7 +1347,12 @@ use_pkg_config(){
>>  }
>>
>>  require_pkg_config(){
>> -    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
>> +    if test $pkg_config != false; then
>> +        use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
>> +    else
>> +        log require_pkg_config "No pkg-config, using require for $@"
>> +        require "$@ -l$1"
>> +    fi
>>  }
>>
>
> pkg-config typically provides more then just a location of the files,
> and while it happens to work for mfx in your case, I don't think this
> generic fallback is a good idea.
> We already require a linux-esque build environment, even for MSVC
> builds (ie. msys or cygwin, etc), having pkg-config on top of the
> other required tools isn't that hard of a dependency to fullfill - I
> do that all the time.
>
> - Hendrik

OK.  Please disregard this patch, and I will submit a different one that 
does something more specific for libmfx.

Thanks,
Aaron Levinson
James Almer April 15, 2017, 1:04 a.m.
On 4/13/2017 9:56 PM, Aaron Levinson wrote:
> From 48f7daba16e0fcdb83d9abd254800c7b9f4ab684 Mon Sep 17 00:00:00 2001
> From: Aaron Levinson <alevinsn@aracnet.com>
> Date: Thu, 13 Apr 2017 17:30:47 -0700
> Subject: [PATCH] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing
> 
> Purpose: Enhanced require_pkg_config() in configure to
> fallback to require() if pkg-config is missing
> 
> Notes: This is likely mainly of relevance when building with MSVC on
> Windows.  In my case, I used this approach to get libmfx when invoking
> configure with --enable-libmfx, which is used for QuickSync (QSV).
> 
> Comments:
> 
> -- configure: Enhanced require_pkg_config() function to first check if
>    $pkg_config is not false.  If not false, it goes through the
>    standard steps of calling use_pkg_config(), but if false, it issues
>    a log message and then calls require() with all the inputted
>    arguments and an additional argument: -l$1.  So, for something like
>    "require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit", this becomes
>    "require libmfx "mfx/mfxvideo.h" MFXInit -llibmfx".  This is not a
>    perfect solution, but the previous approach didn't work at all
>    before when require_pkg_config() is used.
> ---
>  configure | 7 ++++++-
>  1 file changed, 6 insertions(+), 1 deletion(-)
> 
> diff --git a/configure b/configure
> index 7f2b653..ad08b82 100755
> --- a/configure
> +++ b/configure
> @@ -1347,7 +1347,12 @@ use_pkg_config(){
>  }
>  
>  require_pkg_config(){
> -    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
> +    if test $pkg_config != false; then
> +        use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
> +    else
> +        log require_pkg_config "No pkg-config, using require for $@"
> +        require "$@ -l$1"
> +    fi

This will fail in a thousand ways with packages that require other
packages, specific cflags, specific ldflags, or that state specific
versions.
As Hendrik said, pkg-config is not just a fancy way to add -I and -L
options to the compiler and linker.
Aaron Levinson April 15, 2017, 1:54 a.m.
On 4/14/2017 6:04 PM, James Almer wrote:
> On 4/13/2017 9:56 PM, Aaron Levinson wrote:
>> From 48f7daba16e0fcdb83d9abd254800c7b9f4ab684 Mon Sep 17 00:00:00 2001
>> From: Aaron Levinson <alevinsn@aracnet.com>
>> Date: Thu, 13 Apr 2017 17:30:47 -0700
>> Subject: [PATCH] Enhanced require_pkg_config() in configure to fallback to require() if pkg-config is missing
>>
>> Purpose: Enhanced require_pkg_config() in configure to
>> fallback to require() if pkg-config is missing
>>
>> Notes: This is likely mainly of relevance when building with MSVC on
>> Windows.  In my case, I used this approach to get libmfx when invoking
>> configure with --enable-libmfx, which is used for QuickSync (QSV).
>>
>> Comments:
>>
>> -- configure: Enhanced require_pkg_config() function to first check if
>>    $pkg_config is not false.  If not false, it goes through the
>>    standard steps of calling use_pkg_config(), but if false, it issues
>>    a log message and then calls require() with all the inputted
>>    arguments and an additional argument: -l$1.  So, for something like
>>    "require_pkg_config libmfx "mfx/mfxvideo.h" MFXInit", this becomes
>>    "require libmfx "mfx/mfxvideo.h" MFXInit -llibmfx".  This is not a
>>    perfect solution, but the previous approach didn't work at all
>>    before when require_pkg_config() is used.
>> ---
>>  configure | 7 ++++++-
>>  1 file changed, 6 insertions(+), 1 deletion(-)
>>
>> diff --git a/configure b/configure
>> index 7f2b653..ad08b82 100755
>> --- a/configure
>> +++ b/configure
>> @@ -1347,7 +1347,12 @@ use_pkg_config(){
>>  }
>>
>>  require_pkg_config(){
>> -    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
>> +    if test $pkg_config != false; then
>> +        use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
>> +    else
>> +        log require_pkg_config "No pkg-config, using require for $@"
>> +        require "$@ -l$1"
>> +    fi
>
> This will fail in a thousand ways with packages that require other
> packages, specific cflags, specific ldflags, or that state specific
> versions.
> As Hendrik said, pkg-config is not just a fancy way to add -I and -L
> options to the compiler and linker.

I responded earlier today to Hendrik's response and indicated that I was 
abandoning the patch.  I just submitted a new patch that does something 
more specific for libmfx.

Thanks,
Aaron Levinson

Patch hide | download patch | download mbox

diff --git a/configure b/configure
index 7f2b653..ad08b82 100755
--- a/configure
+++ b/configure
@@ -1347,7 +1347,12 @@  use_pkg_config(){
 }
 
 require_pkg_config(){
-    use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
+    if test $pkg_config != false; then
+        use_pkg_config "$@" || die "ERROR: $pkg not found using pkg-config$pkg_config_fail_message"
+    else
+        log require_pkg_config "No pkg-config, using require for $@"
+        require "$@ -l$1"
+    fi
 }
 
 require_libfreetype(){