On Sun, Mar 09, 2008 at 10:51:42AM -0400, Jeff Johnson wrote:
> Meanwhile, below is a rewrite of POPT_fprintf, essentially identical
> to the "man vsnprintf" example. See what you think ...
Looks good. I did some tweaking based on this code. The attached patch
changes what you checked-in to CVS. See if you agree with these points:
1. If the system has vasprintf(), just use that (avoiding issues 2 & 3).
2. Always allocate one more byte than we need, just in case the system's
vsprintf() has an off-by-one bug with the limit.
3. Moved the va_start() and va_end() calls back in the loop because I
believe that the systems that needed a va_copy() in the old code
won't like the reuse of "ap" without it.
Bonus question: I didn't think older systems supported the idiom of
realloc(NULL, len) doing a malloc(). I didn't check to see if that
idiom is already used elsewhere in the popt code, though, so I just
left that alone.
I tested both sides of the HAVE_VASPRINTF code and this seems good to
me.
..wayne..
--- configure.ac 9 Mar 2008 20:24:45 -0000 1.39
+++ configure.ac 9 Mar 2008 21:26:17 -0000
@@ -69,7 +69,7 @@ AM_CONDITIONAL(HAVE_LD_VERSION_SCRIPT, t
AC_CHECK_FUNC(setreuid, [], [
AC_CHECK_LIB(ucb, setreuid, [if echo $LIBS | grep -- -lucb >/dev/null
;then :; else LIBS="$LIBS -lc -lucb" USEUCB=y;fi])
])
-AC_CHECK_FUNCS(getuid geteuid iconv mtrace __secure_getenv setregid stpcpy
strerror)
+AC_CHECK_FUNCS(getuid geteuid iconv mtrace __secure_getenv setregid stpcpy
strerror vasprintf)
AM_GNU_GETTEXT([external])
--- poptint.c 9 Mar 2008 20:24:45 -0000 1.17
+++ poptint.c 9 Mar 2008 21:26:18 -0000
@@ -152,13 +152,17 @@ int
POPT_fprintf (FILE * stream, const char * format, ...)
{
char * b = NULL, * ob = NULL;
- size_t nb = (size_t)1;
int rc;
va_list ap;
+#ifndef HAVE_VASPRINTF
+ size_t nb = (size_t)1;
- va_start(ap, format);
- while ((b = realloc(b, nb)) != NULL) {
+ /* Note that we always allocate 1 byte more than we need, just in
+ * case the vsnprintf() has an off-by-one bug with the limit. */
+ while ((b = realloc(b, nb+1)) != NULL) {
+ va_start(ap, format);
rc = vsnprintf(b, nb, format, ap);
+ va_end(ap);
if (rc > -1) { /* glibc 2.1 */
if ((size_t)rc < nb)
break;
@@ -167,8 +171,16 @@ POPT_fprintf (FILE * stream, const char
nb += (nb < (size_t)100 ? (size_t)100 : nb);
ob = b;
}
+
+#else /* HAVE_VASPRINTF */
+
+ va_start(ap, format);
+ if (vasprintf(&b, format, ap) < 0)
+ b = NULL;
va_end(ap);
+#endif
+
rc = 0;
if (b != NULL) {
#ifdef HAVE_ICONV
