Introduce chk_wmalloc function.

Two-fold benefit. Simplifies code which allocates wchar_t
arrays. Provides overflow check for the multiplication.

* lib.c (chk_wmalloc): New function.
(chk_strdup, mkstring, mkustring, upcase_str, downcase_str,
sub_str, cat_str, trim_str): Use chk_wmalloc.

* lib.h (chk_wmalloc): Declared.

* stream.c (make_string_output_stream): Use chk_wmalloc.

* utf8.c (utf8_dup_from_uc, utf8_dup_from): Likewise.

1 files changed, 1 insertions, 1 deletions

diff --git a/stream.c b/stream.c
index 950e687d..5e249267 100644
--- a/stream.c
+++ b/stream.c
@@ -1553,7 +1553,7 @@ val make_string_output_stream(void)
   struct string_out *so = coerce(struct string_out *, chk_malloc(sizeof *so));
   strm_base_init(&so->a);
   so->size = 128;
-  so->buf = coerce(wchar_t *, chk_malloc(so->size * sizeof so->buf));
+  so->buf = chk_wmalloc(so->size);
   so->fill = 0;
   so->buf[0] = 0;
   utf8_decoder_init(&so->ud);