[Qemu-devel] [PATCH 1/2] This patch adds support for the pselect syscall in linux-user emulation and also adds several support functions required to translate the timespec structs between the target and the host.

[Michael Casadevall]

Signed-off-by: Michael Casadevall <address@hidden>
---
 linux-user/syscall.c |  119 ++++++++++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 119 insertions(+), 0 deletions(-)

diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 9fb493f..3663451 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -850,6 +850,38 @@ static inline abi_long copy_to_user_timeval(abi_ulong 
target_tv_addr,
     return 0;
 }
 
+static inline abi_long copy_from_user_timespec(struct timespec *ts,
+                                              abi_ulong target_ts_addr)
+{
+    struct target_timespec *target_ts;
+
+    if (!lock_user_struct(VERIFY_READ, target_ts, target_ts_addr, 1))
+        return -TARGET_EFAULT;
+
+    __get_user(ts->tv_sec, &target_ts->tv_sec);
+    __get_user(ts->tv_nsec, &target_ts->tv_nsec);
+
+    unlock_user_struct(target_ts, target_ts_addr, 0);
+
+    return 0;
+}
+
+
+static inline abi_long copy_to_user_timespec(abi_ulong target_ts_addr,
+                                            const struct timespec *ts)
+{
+    struct target_timespec *target_ts;
+
+    if (!lock_user_struct(VERIFY_WRITE, target_ts, target_ts_addr, 0))
+        return -TARGET_EFAULT;
+
+    __put_user(ts->tv_sec, &target_ts->tv_sec);
+    __put_user(ts->tv_nsec, &target_ts->tv_nsec);
+
+    unlock_user_struct(target_ts, target_ts_addr, 1);
+
+    return 0;
+}
 #if defined(TARGET_NR_mq_open) && defined(__NR_mq_open)
 #include <mqueue.h>
 
@@ -949,6 +981,75 @@ static abi_long do_select(int n,
     return ret;
 }
 
+#ifdef TARGET_NR_pselect6
+/* do_pselect() must return target values and target errnos. */
+static abi_long do_pselect(int n,
+                          abi_ulong rfd_addr, abi_ulong wfd_addr,
+                          abi_ulong efd_addr, abi_ulong target_tv_addr,
+                          abi_ulong set_addr)
+{
+    fd_set rfds, wfds, efds;
+    fd_set *rfds_ptr, *wfds_ptr, *efds_ptr;
+    struct timespec tv, *tv_ptr;
+    sigset_t set, *set_ptr;
+    abi_long ret;
+
+    if (rfd_addr) {
+        if (copy_from_user_fdset(&rfds, rfd_addr, n))
+            return -TARGET_EFAULT;
+        rfds_ptr = &rfds;
+    } else {
+        rfds_ptr = NULL;
+    }
+    if (wfd_addr) {
+        if (copy_from_user_fdset(&wfds, wfd_addr, n))
+            return -TARGET_EFAULT;
+        wfds_ptr = &wfds;
+    } else {
+        wfds_ptr = NULL;
+    }
+    if (efd_addr) {
+        if (copy_from_user_fdset(&efds, efd_addr, n))
+            return -TARGET_EFAULT;
+        efds_ptr = &efds;
+    } else {
+        efds_ptr = NULL;
+    }
+
+    if (target_tv_addr) {
+        if (copy_from_user_timespec(&tv, target_tv_addr))
+            return -TARGET_EFAULT;
+        tv_ptr = &tv;
+    } else {
+        tv_ptr = NULL;
+    }
+
+    /* We don't need to return sigmask to target */
+    if (set_addr) {
+        target_to_host_old_sigset(&set, &set_addr);
+        set_ptr = &set;
+    } else {
+        set_ptr = NULL;
+    }
+
+    ret = get_errno(pselect(n, rfds_ptr, wfds_ptr, efds_ptr, tv_ptr, set_ptr));
+
+    if (!is_error(ret)) {
+        if (rfd_addr && copy_to_user_fdset(rfd_addr, &rfds, n))
+            return -TARGET_EFAULT;
+        if (wfd_addr && copy_to_user_fdset(wfd_addr, &wfds, n))
+            return -TARGET_EFAULT;
+        if (efd_addr && copy_to_user_fdset(efd_addr, &efds, n))
+            return -TARGET_EFAULT;
+
+        if (target_tv_addr && copy_to_user_timespec(target_tv_addr, &tv))
+            return -TARGET_EFAULT;
+    }
+
+    return ret;
+}
+#endif
+
 static abi_long do_pipe2(int host_pipe[], int flags)
 {
 #ifdef CONFIG_PIPE2
@@ -5136,6 +5237,24 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
         }
         break;
 #endif
+
+#ifdef TARGET_NR_pselect6
+    case TARGET_NR_pselect6:
+        {
+            abi_ulong inp, outp, exp, tvp, set;
+            long nsel;
+
+            nsel = tswapl(arg1);
+            inp = tswapl(arg2);
+            outp = tswapl(arg3);
+            exp = tswapl(arg4);
+            tvp = tswapl(arg5);
+            set = tswapl(arg6);
+
+            ret = do_pselect(nsel, inp, outp, exp, tvp, set);
+        }
+        break;
+#endif
     case TARGET_NR_symlink:
         {
             void *p2;
-- 
1.6.6.1