[Qemu-devel] [PATCH] linux-user: dup3, fallocate syscalls

[Ulrich Hecht]

implementations of dup3 and fallocate that are good enough to fool LTP

updated fallocate check to new configure, added dup3 check as suggested
by Jan-Simon Möller

Signed-off-by: Ulrich Hecht <address@hidden>
---
 configure            |   36 ++++++++++++++++++++++++++++++++++++
 linux-user/syscall.c |   12 ++++++++++++
 2 files changed, 48 insertions(+), 0 deletions(-)

diff --git a/configure b/configure
index 8160bed..2329f88 100755
--- a/configure
+++ b/configure
@@ -1366,6 +1366,36 @@ if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
   splice=yes
 fi
 
+# check for fallocate
+fallocate=no
+cat > $TMPC << EOF
+#include <fcntl.h>
+
+int main(void)
+{
+    fallocate(0, 0, 0, 0);
+    return 0;
+}
+EOF
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
+  fallocate=yes
+fi
+
+# check for dup3
+dup3=no
+cat > $TMPC << EOF
+#include <unistd.h>
+
+int main(void)
+{
+    dup3(0, 0, 0);
+    return 0;
+}
+EOF
+if $cc $ARCH_CFLAGS -o $TMPE $TMPC 2> /dev/null ; then
+  dup3=yes
+fi
+
 # Check if tools are available to build documentation.
 if test "$build_docs" = "yes" -a \( ! -x "`which texi2html 2>/dev/null`" -o ! 
-x "`which pod2man 2>/dev/null`" \) ; then
   build_docs="no"
@@ -1639,6 +1669,12 @@ fi
 if test "$splice" = "yes" ; then
   echo "CONFIG_SPLICE=y" >> $config_host_mak
 fi
+if test "$fallocate" = "yes" ; then
+  echo "CONFIG_FALLOCATE=y" >> $config_host_mak
+fi
+if test "$dup3" = "yes" ; then
+  echo "CONFIG_DUP3=y" >> $config_host_mak
+fi
 if test "$inotify" = "yes" ; then
   echo "CONFIG_INOTIFY=y" >> $config_host_mak
 fi
diff --git a/linux-user/syscall.c b/linux-user/syscall.c
index 31cf151..d105b8e 100644
--- a/linux-user/syscall.c
+++ b/linux-user/syscall.c
@@ -3681,8 +3681,10 @@ static int target_to_host_fcntl_cmd(int cmd)
             return F_SETLEASE;
         case TARGET_F_GETLEASE:
             return F_GETLEASE;
+#ifdef F_DUPFD_CLOEXEC
         case TARGET_F_DUPFD_CLOEXEC:
             return F_DUPFD_CLOEXEC;
+#endif
         case TARGET_F_NOTIFY:
             return F_NOTIFY;
        default:
@@ -4732,6 +4734,11 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
     case TARGET_NR_dup2:
         ret = get_errno(dup2(arg1, arg2));
         break;
+#if defined(TARGET_NR_dup3) && defined(CONFIG_DUP3)
+    case TARGET_NR_dup3:
+        ret = get_errno(dup3(arg1, arg2, arg3));
+        break;
+#endif
 #ifdef TARGET_NR_getppid /* not on alpha */
     case TARGET_NR_getppid:
         ret = get_errno(getppid());
@@ -6976,6 +6983,11 @@ abi_long do_syscall(void *cpu_env, int num, abi_long 
arg1,
         break;
 #endif
 #endif /* CONFIG_SPLICE */
+#if defined(CONFIG_FALLOCATE) && defined(TARGET_NR_fallocate)
+    case TARGET_NR_fallocate:
+        ret = get_errno(fallocate(arg1, arg2, arg3, arg4));
+        break;
+#endif
     default:
     unimplemented:
         gemu_log("qemu: Unsupported syscall: %d\n", num);
-- 
1.6.2.1