linux-user: add support for rt_tgsigqueueinfo() system call

Add a new system call: rt_tgsigqueueinfo().

This system call is similar to rt_sigqueueinfo(), but instead of
sending the signal and data to the whole thread group with the ID
equal to the argument tgid, it sends it to a single thread within
that thread group. The ID of the thread is specified by the tid
argument.

The implementation is based on the rt_sigqueueinfo() in linux-user
mode, where the tid is added as the second argument and the
previous second and third argument become arguments three and four,
respectively.

Signed-off-by: Miloš Stojanović <Milos.Stojanovic@rt-rk.com>

Conflicts:
	linux-user/syscall.c
Signed-off-by: Riku Voipio <riku.voipio@linaro.org>

linux-user/syscall.c

@@ -238,6 +238,7 @@ static type name (type1 arg1,type2 arg2,type3 arg3,type4 arg4,type5 arg5,	\
 #define __NR_sys_getdents64 __NR_getdents64
 #define __NR_sys_getpriority __NR_getpriority
 #define __NR_sys_rt_sigqueueinfo __NR_rt_sigqueueinfo
+#define __NR_sys_rt_tgsigqueueinfo __NR_rt_tgsigqueueinfo
 #define __NR_sys_syslog __NR_syslog
 #define __NR_sys_futex __NR_futex
 #define __NR_sys_inotify_init __NR_inotify_init
@@ -275,6 +276,8 @@ _syscall5(int, _llseek,  uint,  fd, ulong, hi, ulong, lo,
           loff_t *, res, uint, wh);
 #endif
 _syscall3(int, sys_rt_sigqueueinfo, pid_t, pid, int, sig, siginfo_t *, uinfo)
+_syscall4(int, sys_rt_tgsigqueueinfo, pid_t, pid, pid_t, tid, int, sig,
+          siginfo_t *, uinfo)
 _syscall3(int,sys_syslog,int,type,char*,bufp,int,len)
 #ifdef __NR_exit_group
 _syscall1(int,exit_group,int,error_code)
@@ -8872,6 +8875,19 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             ret = get_errno(sys_rt_sigqueueinfo(arg1, arg2, &uinfo));
         }
         break;
+    case TARGET_NR_rt_tgsigqueueinfo:
+        {
+            siginfo_t uinfo;
+
+            p = lock_user(VERIFY_READ, arg4, sizeof(target_siginfo_t), 1);
+            if (!p) {
+                goto efault;
+            }
+            target_to_host_siginfo(&uinfo, p);
+            unlock_user(p, arg4, 0);
+            ret = get_errno(sys_rt_tgsigqueueinfo(arg1, arg2, arg3, &uinfo));
+        }
+        break;
 #ifdef TARGET_NR_sigreturn
     case TARGET_NR_sigreturn:
         if (block_signals()) {