[PATCH 2/2] winetest: Avoid an infinite loop in vstrfmtmake() when the format is NULL.

[Francois Gouget]

From: Francois Gouget

When the format is NULL vsnprintf() always returns -1 so we keep
doubling the allocated memory until running out of memory.
---
For a while I could reproduce this out of memory condition in about 20%
of the runs and determined it probably came from a textOut() call. My
main suspects were:
    report (R_OUT, logname);
    report (R_DIR, tempdir);
These are wrong anyway but for other reasonis. But this issue stopped
happening before I could confirm my suspicions or identify the actual
caller :-(

Anyway printf(NULL) does not crash (with the glibc it's the same as
print("")) so I figure vstrfmtmake() should not either.
---
 programs/winetest/util.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/programs/winetest/util.c b/programs/winetest/util.c
index a1320005841..589810c8fcc 100644
--- a/programs/winetest/util.c
+++ b/programs/winetest/util.c
@@ -56,6 +56,7 @@ static char *vstrfmtmake (size_t *lenp, const char *fmt, va_list ap)
     char *p;
     int n;

+    if (!fmt) fmt = "(noformat)";
     p = xalloc(size);
     while (1) {
         n = vsnprintf (p, size, fmt, ap);