fflush tests: EBADF tests.

* tests/test-fflush.c: Include errno.h, macros.h.
(main): Add tests for EBADF.

1 files changed, 43 insertions, 0 deletions

diff --git a/tests/test-fflush.c b/tests/test-fflush.c
index a6c0e18abb..7c7c474a0a 100644
--- a/tests/test-fflush.c
+++ b/tests/test-fflush.c
@@ -26,8 +26,11 @@
 #include "signature.h"
 SIGNATURE_CHECK (fflush, int, (FILE *));
 
+#include <errno.h>
 #include <unistd.h>
 
+#include "macros.h"
+
 int
 main (void)
 {
@@ -46,6 +49,7 @@ main (void)
 
   /* Test fflush.  */
   f = fopen ("test-fflush.txt", "r");
+  ASSERT (f != NULL);
   fd = fileno (f);
   if (!f || 0 > fd || fread (buffer, 1, 5, f) != 5)
     {
@@ -141,6 +145,45 @@ main (void)
       return 1;
     }
   fclose (f);
+
+  /* Test that fflush() sets errno if someone else closes the stream
+     fd behind the back of stdio.  */
+  {
+    FILE *fp = fopen ("test-fflush.txt", "w");
+    ASSERT (fp != NULL);
+    fputc ('x', fp);
+    ASSERT (close (fileno (fp)) == 0);
+    errno = 0;
+    ASSERT (fflush (fp) == EOF);
+    ASSERT (errno == EBADF);
+    fclose (fp);
+  }
+
+  /* Test that fflush() sets errno if the stream was constructed with
+     an invalid file descriptor.  */
+  {
+    FILE *fp = fdopen (-1, "w");
+    if (fp != NULL)
+      {
+        fputc ('x', fp);
+        errno = 0;
+        ASSERT (fflush (fp) == EOF);
+        ASSERT (errno == EBADF);
+      }
+  }
+  {
+    FILE *fp = fdopen (99, "w");
+    if (fp != NULL)
+      {
+        fputc ('x', fp);
+        errno = 0;
+        ASSERT (fflush (fp) == EOF);
+        ASSERT (errno == EBADF);
+      }
+  }
+
+  /* Clean up.  */
   unlink ("test-fflush.txt");
+
   return 0;
 }