[Qemu-devel] [PATCH 1/2] signal: added a wrapper for sigprocmask function

[Alex Barcelo <abarcelo@ac.upc.edu>]

A transparent wrapper for sigprocmask function.

---
 linux-user/qemu.h    |    1 +
 linux-user/signal.c  |    8 ++++++++
 linux-user/syscall.c |   20 ++++++++++----------
 3 files changed, 19 insertions(+), 10 deletions(-)

diff --git a/linux-user/qemu.h b/linux-user/qemu.h
index fc4cc00..e2dd6a6 100644
--- a/linux-user/qemu.h
+++ b/linux-user/qemu.h
@@ -237,6 +237,7 @@ int host_to_target_signal(int sig);
 long do_sigreturn(CPUArchState *env);
 long do_rt_sigreturn(CPUArchState *env);
 abi_long do_sigaltstack(abi_ulong uss_addr, abi_ulong uoss_addr, abi_ulong sp);
+int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset);
 
 #ifdef TARGET_I386
 /* vm86.c */
diff --git a/linux-user/signal.c b/linux-user/signal.c
index 7869147..b8b8268 100644
--- a/linux-user/signal.c
+++ b/linux-user/signal.c
@@ -5463,6 +5463,14 @@ long do_rt_sigreturn(CPUArchState *env)
 
 #endif
 
+/* Wrapper for sigprocmask function
+ * Emulates a sigprocmask in a safe way for the guest
+ */
+int do_sigprocmask(int how, const sigset_t *set, sigset_t *oldset)
+{
+    return sigprocmask(how, set, oldset);
+}
+
 void process_pending_signals(CPUArchState *cpu_env)
 {
     int sig;
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 471d060..1117bbe 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -4260,7 +4260,7 @@ static void *clone_func(void *arg)
     if (info->parent_tidptr)
         put_user_u32(info->tid, info->parent_tidptr);
     /* Enable signals.  */
-    sigprocmask(SIG_SETMASK, &info->sigmask, NULL);
+    do_sigprocmask(SIG_SETMASK, &info->sigmask, NULL);
     /* Signal to the parent that we're ready.  */
     pthread_mutex_lock(&info->mutex);
     pthread_cond_broadcast(&info->cond);
@@ -4351,12 +4351,12 @@ static int do_fork(CPUArchState *env, unsigned int flags, abi_ulong newsp,
         /* It is not safe to deliver signals until the child has finished
            initializing, so temporarily block all signals.  */
         sigfillset(&sigmask);
-        sigprocmask(SIG_BLOCK, &sigmask, &info.sigmask);
+        do_sigprocmask(SIG_BLOCK, &sigmask, &info.sigmask);
 
         ret = pthread_create(&info.thread, &attr, clone_func, &info);
         /* TODO: Free new CPU state if thread creation failed.  */
 
-        sigprocmask(SIG_SETMASK, &info.sigmask, NULL);
+        do_sigprocmask(SIG_SETMASK, &info.sigmask, NULL);
         pthread_attr_destroy(&attr);
         if (ret == 0) {
             /* Wait for the child to initialize.  */
@@ -5875,7 +5875,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         {
             sigset_t cur_set;
             abi_ulong target_set;
-            sigprocmask(0, NULL, &cur_set);
+            do_sigprocmask(0, NULL, &cur_set);
             host_to_target_old_sigset(&target_set, &cur_set);
             ret = target_set;
         }
@@ -5886,10 +5886,10 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
         {
             sigset_t set, oset, cur_set;
             abi_ulong target_set = arg1;
-            sigprocmask(0, NULL, &cur_set);
+            do_sigprocmask(0, NULL, &cur_set);
             target_to_host_old_sigset(&set, &target_set);
             sigorset(&set, &set, &cur_set);
-            sigprocmask(SIG_SETMASK, &set, &oset);
+            do_sigprocmask(SIG_SETMASK, &set, &oset);
             host_to_target_old_sigset(&target_set, &oset);
             ret = target_set;
         }
@@ -5920,7 +5920,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             mask = arg2;
             target_to_host_old_sigset(&set, &mask);
 
-            ret = get_errno(sigprocmask(how, &set, &oldset));
+            ret = get_errno(do_sigprocmask(how, &set, &oldset));
             if (!is_error(ret)) {
                 host_to_target_old_sigset(&mask, &oldset);
                 ret = mask;
@@ -5954,7 +5954,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
                 how = 0;
                 set_ptr = NULL;
             }
-            ret = get_errno(sigprocmask(how, set_ptr, &oldset));
+            ret = get_errno(do_sigprocmask(how, set_ptr, &oldset));
             if (!is_error(ret) && arg3) {
                 if (!(p = lock_user(VERIFY_WRITE, arg3, sizeof(target_sigset_t), 0)))
                     goto efault;
@@ -5994,7 +5994,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
                 how = 0;
                 set_ptr = NULL;
             }
-            ret = get_errno(sigprocmask(how, set_ptr, &oldset));
+            ret = get_errno(do_sigprocmask(how, set_ptr, &oldset));
             if (!is_error(ret) && arg3) {
                 if (!(p = lock_user(VERIFY_WRITE, arg3, sizeof(target_sigset_t), 0)))
                     goto efault;
@@ -7870,7 +7870,7 @@ abi_long do_syscall(void *cpu_env, int num, abi_long arg1,
             }
             mask = arg2;
             target_to_host_old_sigset(&set, &mask);
-            sigprocmask(how, &set, &oldset);
+            do_sigprocmask(how, &set, &oldset);
             host_to_target_old_sigset(&mask, &oldset);
             ret = mask;
         }
-- 
1.7.5.4