DBus-proxy fails to compile on musl-based systems

[AbsolutelyLudicrous]

Linux distribution and version

KISS Linux, rolling (source based, close to being LFS)

Flatpak version

1.6.0 and 1.6.1 were both tested

Description of problem

Building Flatpak fails due to dbus-proxy not compiling. This occurs both when using --without-system-dbus-proxy and --with-system-dbus-proxy; in the case of the latter, flatpak/xdg-dbus-proxy fails to compile in the same file.

Here's the text of the error message:

  CC       dbus-proxy/flatpak_dbus_proxy-dbus-proxy.o
dbus-proxy/dbus-proxy.c: In function ‘fd_readall_bytes’:
dbus-proxy/dbus-proxy.c:47:7: error: implicit declaration of function ‘TEMP_FAILURE_RETRY’ [-Werror=implicit-function-declaration]
   47 |   if (TEMP_FAILURE_RETRY (fstat (fd, &stbuf)) != 0)
      |       ^~~~~~~~~~~~~~~~~~
cc1: some warnings being treated as errors
make[2]: *** [Makefile:4525: dbus-proxy/flatpak_dbus_proxy-dbus-proxy.o] Error 1

When trying to build flatpak/xdg-dbus-proxy, the build fails in about the same spot:

  CC       dbus-proxy.o
dbus-proxy.c: In function ‘fd_readall_bytes’:
dbus-proxy.c:73:7: warning: implicit declaration of function ‘TEMP_FAILURE_RETRY’ [-Wimplicit-function-declaration]
   73 |   if (TEMP_FAILURE_RETRY (fstat (fd, &stbuf)) != 0)
      |       ^~~~~~~~~~~~~~~~~~
  CCLD     xdg-dbus-proxy
/usr/lib/gcc/x86_64-pc-linux-musl/9.2.0/../../../../x86_64-pc-linux-musl/bin/ld: dbus-proxy.o: in function `fd_readall_bytes':
/root/.cache/kiss/build-30335/xdg-dbus-proxy/dbus-proxy.c:73: undefined reference to `TEMP_FAILURE_RETRY'
collect2: error: ld returned 1 exit status
make[1]: *** [Makefile:903: xdg-dbus-proxy] Error 1

Steps to reproduce

Build Flatpak on x86_64-pc-linux-musl, I guess.

Here's what I have as dependencies:

autoconf make
automake make
libtool make
bison make
gettext
libcap
libarchive
libxml2
libsoup
gpgme
libXau
linux-headers
polkit
json-glib
appstream-glib
dbus
bubblewrap

And here's my build script:

#!/bin/sh -e

patch -p0 -N -i musl-macros.patch

autoreconf -fi

./configure --prefix=/usr --disable-seccomp --disable-documentation --disable-gtk-doc --with-system-bubblewrap --without-system-dbus-proxy --enable-sandboxed-triggers
make ${MAKEOPTS}
make install DESTDIR=$1

And here's the contents of musl-macros.patch, which I stole from Void Linux's port of Flatpak:

--- config.h.in.orig
+++ config.h.in
@@ -151,3 +151,12 @@
 
 /* Define to 1 if you need to in order for `stat' and other things to work. */
 #undef _POSIX_SOURCE
+
+#ifndef TEMP_FAILURE_RETRY
+#define TEMP_FAILURE_RETRY(expression) \
+  (__extension__                                                              \
+    ({ long int __result;                                                     \
+       do __result = (long int) (expression);                                 \
+       while (__result == -1L && errno == EINTR);                             \
+       __result; }))
+#endif

[smcv]

This is not really a Flatpak bug, so I've transferred it to xdg-dbus-proxy, where it is a duplicate of #19.

For the --with-system-dbus-proxy case, this should be fixed by using a system copy of xdg-dbus-proxy >= 0.1.3, as a result of #13.

Flatpak 1.13.1 will include xdg-dbus-proxy 0.1.3, resolving this for the --without-system-dbus-proxy case.