Function psprintf

src/common/psprintf.c:45–76

* psprintf * * Format text data under the control of fmt (an sprintf-style format string) * and return it in an allocated-on-demand buffer. The buffer is allocated * with palloc in the backend, or malloc in frontend builds. Caller is * responsible to free the buffer when no longer needed, if appropriate. * * Errors are not returned to the caller, but are reported via elog(ERROR) * in the

 * One should therefore think twice about using this in libpq.
 */
char *
psprintf(const char *fmt,...)
{
	int			save_errno = errno;
	size_t		len = 128;		/* initial assumption about buffer size */

	for (;;)
	{
		char	   *result;
		va_list		args;
		size_t		newlen;

		/*
		 * Allocate result buffer.  Note that in frontend this maps to malloc
		 * with exit-on-error.
		 */
		result = (char *) palloc(len);

		/* Try to format the data. */
		errno = save_errno;
		va_start(args, fmt);
		newlen = pvsnprintf(result, len, fmt, args);
		va_end(args);

		if (newlen < len)
			return result;		/* success */

		/* Release buffer and loop around to try again with larger len. */
		pfree(result);
		len = newlen;
	}
}

/*
 * pvsnprintf