Rewrite iconv option parsing [BZ #19519]

This commit replaces string manipulation during `iconv_open' and iconv_prog
option parsing with a structured, flag based conversion specification.  In
doing so, it alters the internal `__gconv_open' interface and accordingly
adjusts its uses.

This change fixes several hangs in the iconv program and therefore includes
a new test to exercise iconv_prog options that originally led to these hangs.
It also includes a new regression test for option handling in the iconv
function.

Reviewed-by: Florian Weimer <fweimer@redhat.com>
Reviewed-by: Siddhesh Poyarekar <siddhesh@sourceware.org>
Reviewed-by: Carlos O'Donell <carlos@redhat.com>

1 files changed, 15 insertions, 4 deletions

diff --git a/iconv/gconv_int.h b/iconv/gconv_int.h
index fbaf12cee2..e86938dae7 100644
--- a/iconv/gconv_int.h
+++ b/iconv/gconv_int.h
@@ -75,6 +75,15 @@ struct gconv_module
 };
 
 
+/* The specification of the conversion that needs to be performed.  */
+struct gconv_spec
+{
+  char *fromcode;
+  char *tocode;
+  bool translit;
+  bool ignore;
+};
+
 /* Flags for `gconv_open'.  */
 enum
 {
@@ -136,10 +145,12 @@ __libc_lock_define (extern, __gconv_lock attribute_hidden)
   })
 
 
-/* Return in *HANDLE decriptor for transformation from FROMSET to TOSET.  */
-extern int __gconv_open (const char *toset, const char *fromset,
-			 __gconv_t *handle, int flags)
-     attribute_hidden;
+/* Return in *HANDLE, a decriptor for the transformation.  The function expects
+   the specification of the transformation in the structure pointed to by
+   CONV_SPEC.  It only reads *CONV_SPEC and does not take ownership of it.  */
+extern int __gconv_open (struct gconv_spec *conv_spec,
+                         __gconv_t *handle, int flags);
+libc_hidden_proto (__gconv_open)
 
 /* Free resources associated with transformation descriptor CD.  */
 extern int __gconv_close (__gconv_t cd)