[Buildroot] [PATCH 1/1] package/upmpdcli: Add patch to fix OPEN_MAX build error

[Buildroot] [PATCH 1/1] package/upmpdcli: Add patch to fix OPEN_MAX build error

[Jörg Krause]

Not all systems define POSIX.1 value OPEN_MAX. In this case just close
all descriptors up to some arbitrary limit - say 256 [1].

Fixes:
http://autobuild.buildroot.net/results/d66/d660a9409552b3e1ad9e3ed716386fd0a67fd8db
http://autobuild.buildroot.net/results/f19/f19e843cdcc968a72919ca3792a90dd40552bd59
http://autobuild.buildroot.net/results/a77/a776001dae51c4dae1f25b3a9bf9a9fe2ca69003
http://autobuild.buildroot.net/results/3e7/3e7590566ed3cc7a1dd412fb66b7b987e847aa25

and many more.

Pull request is opened on github [2].

[1]
Advanced Programming in the UNIX Environment, Richard Stevens, p. 52.

[2]
https://github.com/medoc92/upmpdcli/pull/13

Signed-off-by: J?rg Krause <joerg.krause@embedded.rocks>
---
 .../0001-Fix-undefined-OPEN_MAX-error.patch        | 37 ++++++++++++++++++++++
 1 file changed, 37 insertions(+)
 create mode 100644 package/upmpdcli/0001-Fix-undefined-OPEN_MAX-error.patch

diff --git a/package/upmpdcli/0001-Fix-undefined-OPEN_MAX-error.patch b/package/upmpdcli/0001-Fix-undefined-OPEN_MAX-error.patch
new file mode 100644
index 0000000..d74eb99
--- /dev/null
+++ b/package/upmpdcli/0001-Fix-undefined-OPEN_MAX-error.patch
@@ -0,0 +1,37 @@
+From eb2fb0b2ce8987c5288c571cfb0586710c4486bb Mon Sep 17 00:00:00 2001
+From: =?UTF-8?q?J=C3=B6rg=20Krause?= <joerg.krause@embedded.rocks>
+Date: Thu, 16 Jul 2015 22:24:13 +0200
+Subject: [PATCH 1/1] Fix undefined OPEN_MAX error
+MIME-Version: 1.0
+Content-Type: text/plain; charset=UTF-8
+Content-Transfer-Encoding: 8bit
+
+Not all systems define POSIX.1 value OPEN_MAX. In this case just close
+all descriptors up to some arbitrary limit - say 256 [1].
+
+[1]
+Advanced Programming in the UNIX Environment, Richard Stevens, p. 52.
+
+Signed-off-by: J?rg Krause <joerg.krause@embedded.rocks>
+---
+ src/closefrom.cpp | 4 ++++
+ 1 file changed, 4 insertions(+)
+
+diff --git a/src/closefrom.cpp b/src/closefrom.cpp
+index a713875..4429b20 100644
+--- a/src/closefrom.cpp
++++ b/src/closefrom.cpp
+@@ -154,6 +154,10 @@ int libclf_closefrom(int fd0)
+ 
+ static int closefrom_maxfd = -1;
+ 
++#ifndef OPEN_MAX
++#define OPEN_MAX 256 /* Guess */
++#endif
++
+ void libclf_setmaxfd(int max)
+ {
+     closefrom_maxfd = max;
+-- 
+2.4.6
+
-- 
2.4.6

[Buildroot] [PATCH 1/1] package/upmpdcli: Add patch to fix OPEN_MAX build error

[Thomas Petazzoni]

Dear J?rg Krause,

On Thu, 16 Jul 2015 22:53:12 +0200, J?rg Krause wrote:

> ++#ifndef OPEN_MAX
> ++#define OPEN_MAX 256 /* Guess */
> ++#endif
> ++

This is not the right fix. There is some Linux-specific code in
closefrom.cpp, but it doesn't get used since when you build C++ code
with -std=c++0x, the compiler doesn't define "linux" or "__linux", but
"__linux__", so the following test doesn't work anymore:

#elif (defined(linux) || defined(__linux))

See what the compiler does, without -std=c++0x:

$ ./output/host/usr/bin/powerpc-linux-g++ -dM -E - < /dev/null | grep -i linux#define __linux 1
#define __linux__ 1
#define __gnu_linux__ 1
#define linux 1

And now, with -std=c++0x:

$ ./output/host/usr/bin/powerpc-linux-g++ -std=c++0x -dM -E - < /dev/null | grep -i linux
#define __linux__ 1
#define __gnu_linux__ 1

So, just change the closefrom.cpp Linux test to:

#elif (defined(linux) || defined(__linux) || defined(__linux__))

and it will build fine, and be a lot better than a guessed 256 value.
Can you submit a new patch that does this, and report the proper
solution upstream?

Thanks!

Thomas
-- 
Thomas Petazzoni, CTO, Free Electrons
Embedded Linux, Kernel and Android engineering
http://free-electrons.com

[Buildroot] [PATCH 1/1] package/upmpdcli: Add patch to fix OPEN_MAX build error

[Jörg Krause]

Dear Thomas Petazzoni,

On Sa, 2015-07-18 at 14:36 +0200, Thomas Petazzoni wrote:
> Dear J?rg Krause,
> 
> On Thu, 16 Jul 2015 22:53:12 +0200, J?rg Krause wrote:
> 
> > ++#ifndef OPEN_MAX
> > ++#define OPEN_MAX 256 /* Guess */
> > ++#endif
> > ++
> 
> This is not the right fix. There is some Linux-specific code in
> closefrom.cpp, but it doesn't get used since when you build C++ code
> with -std=c++0x, the compiler doesn't define "linux" or "__linux", 
> but
> "__linux__", so the following test doesn't work anymore:
> 
> #elif (defined(linux) || defined(__linux))
> 
> See what the compiler does, without -std=c++0x:
> 
> $ ./output/host/usr/bin/powerpc-linux-g++ -dM -E - < /dev/null | grep 
> -i linux#define __linux 1
> #define __linux__ 1
> #define __gnu_linux__ 1
> #define linux 1
> 
> And now, with -std=c++0x:
> 
> $ ./output/host/usr/bin/powerpc-linux-g++ -std=c++0x -dM -E - < 
> /dev/null | grep -i linux
> #define __linux__ 1
> #define __gnu_linux__ 1
> 
> So, just change the closefrom.cpp Linux test to:
> 
> #elif (defined(linux) || defined(__linux) || defined(__linux__))
> 
> and it will build fine, and be a lot better than a guessed 256 value.
> Can you submit a new patch that does this, and report the proper
> solution upstream?

I see! You're right, it works. I'll submit a new patch.

Best regards
J?rg Krause