history_msg->cm_fields['M'] = realloc(history_msg->cm_fields['M'],
strlen(history_msg->cm_fields['M']) + strlen(diffbuf) + 512
);
history_msg->cm_fields['M'] = realloc(history_msg->cm_fields['M'],
strlen(history_msg->cm_fields['M']) + strlen(diffbuf) + 512
);