[UNIKRAFT PATCH 08/10] lib/vfscore: Register `dup` to syscall_shim

[Constantin Raducanu <raducanu.costi@xxxxxxxxx>]

Registers `dup` 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        | 10 ++++++----
 3 files changed, 9 insertions(+), 4 deletions(-)

diff --git a/lib/vfscore/Makefile.uk b/lib/vfscore/Makefile.uk
index 68d108c..a1570ed 100644
--- a/lib/vfscore/Makefile.uk
+++ b/lib/vfscore/Makefile.uk
@@ -41,3 +41,4 @@ UK_PROVIDED_SYSCALLS-$(CONFIG_LIBVFSCORE) += chmod-2
 UK_PROVIDED_SYSCALLS-$(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
diff --git a/lib/vfscore/exportsyms.uk b/lib/vfscore/exportsyms.uk
index 583a75e..e16fa90 100644
--- a/lib/vfscore/exportsyms.uk
+++ b/lib/vfscore/exportsyms.uk
@@ -44,6 +44,8 @@ uk_syscall_e_fchmod
 uk_syscall_r_fchmod
 fchown
 dup
+uk_syscall_e_dup
+uk_syscall_r_dup
 dup2
 dup3
 sync
diff --git a/lib/vfscore/main.c b/lib/vfscore/main.c
index c6e446a..67344f9 100644
--- a/lib/vfscore/main.c
+++ b/lib/vfscore/main.c
@@ -1395,7 +1395,7 @@ int dup(int oldfd)
        trace_vfs_dup(oldfd);
        error = fget(oldfd, &fp);
        if (error)
-               goto out_errno;
+               goto out_error;
 
        error = fdalloc(fp, &newfd);
        if (error)
@@ -1407,10 +1407,12 @@ int dup(int oldfd)
 
        out_fdrop:
        fdrop(fp);
-       out_errno:
+
+       out_error:
        trace_vfs_dup_err(error);
-       errno = error;
-       return -1;
+       if(error > 0)
+               return -error;
+       return error;
 }
 
 UK_TRACEPOINT(trace_vfs_dup3, "%d %d 0x%x", int, int, int);
-- 
2.17.1