+#ifdef WGET_USE_STDARG
+# define VA_START(args, arg1) va_start (args, arg1)
+#else
+# define VA_START(args, ignored) va_start (args)
+#endif
+
+/* Like sprintf, but allocates a string of sufficient size with malloc
+ and returns it. GNU libc has a similar function named asprintf,
+ which requires the pointer to the string to be passed. */
+
+char *
+aprintf (const char *fmt, ...)
+{
+ /* This function is implemented using vsnprintf, which we provide
+ for the systems that don't have it. Therefore, it should be 100%
+ portable. */
+
+ int size = 32;
+ char *str = xmalloc (size);
+
+ while (1)
+ {
+ int n;
+ va_list args;
+
+ /* See log_vprintf_internal for explanation why it's OK to rely
+ on the return value of vsnprintf. */
+
+ VA_START (args, fmt);
+ n = vsnprintf (str, size, fmt, args);
+ va_end (args);
+
+ /* If the printing worked, return the string. */
+ if (n > -1 && n < size)
+ return str;
+
+ /* Else try again with a larger buffer. */
+ if (n > -1) /* C99 */
+ size = n + 1; /* precisely what is needed */
+ else
+ size <<= 1; /* twice the old size */
+ str = xrealloc (str, size);
+ }
+ return NULL; /* unreached */
+}
+\f