[Libunwind-devel] [patch 1/3] tests/: test-resume-sig false PASS on non-ia64

[Jan Kratochvil]

Hi,

currently the testcases PASSes on non-ia64 with upstream GLIBC snapshot but it
should FAIL there as the tested functionality is not implemented on non-ia64
platforms.



2006-12-10  Jan Kratochvil  <address@hidden>

        * tests/Gtest-resume-sig.c (handler): Fixed false PASS on non-ia64.
        Be adaptive to the number of unwinding steps from `SIGUSR1'.

--- ./tests/Gtest-resume-sig.c  31 May 2006 18:22:16 -0000      1.1
+++ ./tests/Gtest-resume-sig.c  10 Dec 2006 14:31:14 -0000      1.2
@@ -32,6 +32,7 @@ WITH THE SOFTWARE OR THE USE OR OTHER DE
 #include <stdio.h>
 #include <stdlib.h>
 #include <unistd.h>
+#include <string.h>
 
 #ifdef HAVE_IA64INTRIN_H
 # include <ia64intrin.h>
@@ -68,6 +69,7 @@ handler (int sig)
   unw_cursor_t c;
   char foo;
   int ret;
+  int stepno;
 
 #if UNW_TARGET_IA64
   if (verbose)
@@ -95,11 +97,32 @@ handler (int sig)
       if ((ret = unw_init_local (&c, &uc)) < 0)
        panic ("unw_init_local() failed: ret=%d\n", ret);
 
-      if ((ret = unw_step (&c)) < 0)           /* step to signal trampoline */
-       panic ("unw_step(1) failed: ret=%d\n", ret);
-
-      if ((ret = unw_step (&c)) < 0)           /* step to signal trampoline */
-       panic ("unw_step(2) failed: ret=%d\n", ret);
+      /* After fixing glibc's `__restore_rt' unwinding by CFI in:
+               
http://sources.redhat.com/cgi-bin/cvsweb.cgi/libc/sysdeps/unix/sysv/linux/x86_64/sigaction.c.diff?cvsroot=glibc&r1=text&tr1=1.10&r2=text&tr2=1.12&f=u
+        This test started failing as the original code stepped back directly
+        out of `main' into `__libc_start_main' and so despite `SIGUSR2' was
+        never hit (at least on GNU/Linux) the test PASSed due to exit code 0.
+        Patch fixing the unwind is in Fedora Core glibc-2.5.90-11 upwards.
+        Needing to implement also non-ia64 `resume_restores_sigmask'.  */
+
+      for (stepno = 0;; stepno++)
+        {
+         char buf[512];
+
+         if ((ret = unw_get_proc_name (&c, buf, sizeof (buf), NULL)) < 0)
+           panic ("unw_get_proc_name(%d) failed: ret=%d\n", stepno, ret);
+         else
+           {
+             if (verbose)
+               printf ("unw_get_proc_name(%d): %s\n", stepno, buf);
+             if (!strcmp (buf, "kill") || !strcmp (buf, "main"))
+               break;
+           }
+
+         /* Step one frame behind `main' to get into `__libc_start_main'.  */
+         if ((ret = unw_step (&c)) < 0)
+           panic ("unw_step(%d) failed: ret=%d\n", stepno, ret);
+       }
 
       if ((ret = unw_get_reg (&c, UNW_REG_IP, &ip)) < 0)
        panic ("unw_get_reg(IP) failed: ret=%d\n", ret);