[Qemu-devel] [PATCH v2] linux-user/signal.c: define __SIGRTMIN/MAX for non-GNU platforms

[Natanael Copa]

The __SIGRTMIN and __SIGRTMAX are glibc internals and are not available
on all platforms, so we define those if they are missing. We also check
that those corresponds with the posix variables SIGRTMIN/SIGRTMAX which
may only be available during runtime.

This is needed for musl libc.

Signed-off-by: Natanael Copa <address@hidden>
---
Changes v1 -> v2:
 - replace NSIG with _NSIG since thats use everywhere else in the code.
 - add runtime asserts.

 linux-user/signal.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/linux-user/signal.c b/linux-user/signal.c
index 5b8a01f..67771ad 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -32,6 +32,13 @@
 
 //#define DEBUG_SIGNAL
 
+#ifndef __SIGRTMIN
+#define __SIGRTMIN 32
+#endif
+#ifndef __SIGRTMAX
+#define __SIGRTMAX (_NSIG-1)
+#endif
+
 static struct target_sigaltstack target_sigaltstack_used = {
     .ss_sp = 0,
     .ss_size = 0,
@@ -379,6 +386,13 @@ void signal_init(void)
     int i, j;
     int host_sig;
 
+    /* SIGRTMIN/SIGRTMAX might be runtime variables so we cannot use them
+       to declare the host_to_target_signal table. But we are interacting
+       with a given kernel where the values will be fixed. Check that the
+       runtime values actually corresponds. */
+    assert(__SIGRTMIN == SIGRTMIN);
+    assert(__SIGRTMAX == SIGRTMAX);
+
     /* generate signal conversion tables */
     for(i = 1; i < _NSIG; i++) {
         if (host_to_target_signal_table[i] == 0)
-- 
2.0.0