[UNIKRAFT PATCH 09/10] lib/vfscore: Register `dup3` to syscall_shim

[Constantin Raducanu <raducanu.costi@xxxxxxxxx>]

Registers `dup3` system call to syscall_shim library.

Signed-off-by: Constantin Raducanu <raducanu.costi@xxxxxxxxx>
---
 lib/vfscore/Makefile.uk   |  1 +
 lib/vfscore/exportsyms.uk |  2 ++
 lib/vfscore/main.c        | 21 +++++++++++----------
 3 files changed, 14 insertions(+), 10 deletions(-)

diff --git a/lib/vfscore/Makefile.uk b/lib/vfscore/Makefile.uk
index a1570ed..0919de7 100644
--- a/lib/vfscore/Makefile.uk
+++ b/lib/vfscore/Makefile.uk
@@ -42,3 +42,4 @@ UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fchmod-2
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += chdir-1
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += fchdir-1
 UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += dup-1
+UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += dup3-3
diff --git a/lib/vfscore/exportsyms.uk b/lib/vfscore/exportsyms.uk
index e16fa90..ead0d9f 100644
--- a/lib/vfscore/exportsyms.uk
+++ b/lib/vfscore/exportsyms.uk
@@ -48,6 +48,8 @@ uk_syscall_e_dup
 uk_syscall_r_dup
 dup2
 dup3
+uk_syscall_e_dup3
+uk_syscall_r_dup3
 sync
 vfscore_mount_dump
 umount
diff --git a/lib/vfscore/main.c b/lib/vfscore/main.c
index 67344f9..dc8f9e2 100644
--- a/lib/vfscore/main.c
+++ b/lib/vfscore/main.c
@@ -1421,7 +1421,7 @@ UK_TRACEPOINT(trace_vfs_dup3_err, "%d", int);
 /*
  * Duplicate a file descriptor to a particular value.
  */
-int dup3(int oldfd, int newfd, int flags)
+UK_SYSCALL_R_DEFINE(int, dup3, int, oldfd, int, newfd, int, flags)
 {
        struct vfscore_file *fp, *fp_new;
        int error;
@@ -1433,44 +1433,45 @@ int dup3(int oldfd, int newfd, int flags)
         */
        if ((flags & ~O_CLOEXEC) != 0) {
                error = EINVAL;
-               goto out_errno;
+               goto out_error;
        }
 
        if (oldfd == newfd) {
                error = EINVAL;
-               goto out_errno;
+               goto out_error;
        }
 
        error = fget(oldfd, &fp);
        if (error)
-               goto out_errno;
+               goto out_error;
 
        error = fget(newfd, &fp_new);
        if (error == 0) {
                /* if newfd is open, then close it */
                error = close(newfd);
                if (error)
-                       goto out_errno;
+                       goto out_error;
        }
 
        error = vfscore_reserve_fd(newfd);
        if (error)
-               goto out_errno;
+               goto out_error;
 
        error = vfscore_install_fd(newfd, fp);
        if (error) {
                fdrop(fp);
-               goto out_errno;
+               goto out_error;
        }
 
        fdrop(fp);
        trace_vfs_dup3_ret(newfd);
        return newfd;
 
-       out_errno:
+       out_error:
        trace_vfs_dup3_err(error);
-       errno = error;
-       return -1;
+       if(error > 0)
+               return -error;
+       return error;
 }
 
 int dup2(int oldfd, int newfd)
-- 
2.17.1