[PATCH] regedit: Don't crash if REG_SZ is empty

[Fabian Maurer]

Some reg files can result in an REG_SZ with length 0, like
"Value"=hex(1):
When exporting with size == 0 we need to account for this case
and set the length to 0 to avoid an underflow.

Signed-off-by: Fabian Maurer <dark.shadow4 at web.de>
---
 programs/regedit/regproc.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/programs/regedit/regproc.c b/programs/regedit/regproc.c
index 6e6ea473c7..aa1d6fa90f 100644
--- a/programs/regedit/regproc.c
+++ b/programs/regedit/regproc.c
@@ -1243,11 +1243,12 @@ static size_t export_value_name(FILE *fp, WCHAR *name, size_t len, BOOL unicode)
 
 static void export_string_data(WCHAR **buf, WCHAR *data, size_t size)
 {
-    size_t len, line_len;
+    size_t len = 0, line_len;
     WCHAR *str;
     static const WCHAR fmt[] = {'"','%','s','"',0};
 
-    len = size / sizeof(WCHAR) - 1;
+    if(size)
+        len = size / sizeof(WCHAR) - 1;
     str = REGPROC_escape_string(data, len, &line_len);
     *buf = heap_xalloc((line_len + 3) * sizeof(WCHAR));
     sprintfW(*buf, fmt, str);
-- 
2.14.2