alpha-linux-user: Fix signal handling

Proper signal numbers were not defined, and EXCP_INTERRUPT
was unhandled, leading to all sorts of subtle confusion.
Reviewed-by: NPeter Maydell <peter.maydell@linaro.org>
Signed-off-by: NRichard Henderson <rth@twiddle.net>

linux-user/main.c

@@ -2921,6 +2921,9 @@ void cpu_loop(CPUAlphaState *env)
         case EXCP_STQ_C:
             do_store_exclusive(env, env->error_code, trapnr - EXCP_STL_C);
             break;
+        case EXCP_INTERRUPT:
+            /* Just indicate that signals should be handled asap.  */
+            break;
         default:
             printf ("Unhandled trap: 0x%x\n", trapnr);
             cpu_dump_state(env, stderr, fprintf, 0);

linux-user/syscall_defs.h

@@ -371,7 +371,46 @@ int do_sigaction(int sig, const struct target_sigaction *act,
 #define TARGET_SA_RESTORER	0x04000000
 #endif
 
-#if defined(TARGET_SPARC)
+#if defined(TARGET_ALPHA)
+
+#define TARGET_SIGHUP            1
+#define TARGET_SIGINT            2
+#define TARGET_SIGQUIT           3
+#define TARGET_SIGILL            4
+#define TARGET_SIGTRAP           5
+#define TARGET_SIGABRT           6
+#define TARGET_SIGSTKFLT         7 /* actually SIGEMT */
+#define TARGET_SIGFPE            8
+#define TARGET_SIGKILL           9
+#define TARGET_SIGBUS           10
+#define TARGET_SIGSEGV          11
+#define TARGET_SIGSYS           12
+#define TARGET_SIGPIPE          13
+#define TARGET_SIGALRM          14
+#define TARGET_SIGTERM          15
+#define TARGET_SIGURG           16
+#define TARGET_SIGSTOP          17
+#define TARGET_SIGTSTP          18
+#define TARGET_SIGCONT          19
+#define TARGET_SIGCHLD          20
+#define TARGET_SIGTTIN          21
+#define TARGET_SIGTTOU          22
+#define TARGET_SIGIO            23
+#define TARGET_SIGXCPU          24
+#define TARGET_SIGXFSZ          25
+#define TARGET_SIGVTALRM        26
+#define TARGET_SIGPROF          27
+#define TARGET_SIGWINCH         28
+#define TARGET_SIGPWR           29 /* actually SIGINFO */
+#define TARGET_SIGUSR1          30
+#define TARGET_SIGUSR2          31
+#define TARGET_SIGRTMIN         32
+
+#define TARGET_SIG_BLOCK         1
+#define TARGET_SIG_UNBLOCK       2
+#define TARGET_SIG_SETMASK       3
+
+#elif defined(TARGET_SPARC)
 
 #define TARGET_SIGHUP		 1
 #define TARGET_SIGINT		 2