Function parseVariable

src/bin/pgbench/pgbench.c:1709–1734

* Parse a possible variable reference (:varname). * * "sql" points at a colon. If what follows it looks like a valid * variable name, return a malloc'd string containing the variable name, * and set *eaten to the number of characters consumed (including the colon). * Otherwise, return NULL. */

 * Otherwise, return NULL.
 */
static char *
parseVariable(const char *sql, int *eaten)
{
	int			i = 1;			/* starting at 1 skips the colon */
	char	   *name;

	/* keep this logic in sync with valid_variable_name() */
	if (IS_HIGHBIT_SET(sql[i]) ||
		strchr("ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz"
			   "_", sql[i]) != NULL)
		i++;
	else
		return NULL;

	while (IS_HIGHBIT_SET(sql[i]) ||
		   strchr("ABCDEFGHIJKLMNOPQRSTUVWXYZ" "abcdefghijklmnopqrstuvwxyz"
				  "_0123456789", sql[i]) != NULL)
		i++;

	name = pg_malloc(i);
	memcpy(name, &sql[1], i - 1);
	name[i - 1] = '\0';

	*eaten = i;
	return name;
}

static char *
replaceVariable(char **sql, char *param, int len, char *value)