merges r28577 from trunk into ruby_1_9_2.

--
* string.c (rb_str_conv_enc_opts): fix infinite loop because
  of ISO-2022-JP conversion with empty string.
  patched by Brian Buchanan [ruby-core:31107]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@28605 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 1 deletions

diff --git a/string.c b/string.c
index 8cfbb56bdf..1b06370bb7 100644
--- a/string.c
+++ b/string.c
@@ -513,7 +513,7 @@ rb_str_conv_enc_opts(VALUE str, rb_encoding *from, rb_encoding *to, int ecflags,
     switch (ret) {
       case econv_destination_buffer_full:
 	/* destination buffer short */
-	len *= 2;
+	len = len < 2 ? 2 : len * 2;
 	rb_str_resize(newstr, len);
 	goto retry;