(* Memory info for virtual domains. (C) Copyright 2008 Richard W.M. Jones, Red Hat Inc. http://libvirt.org/ This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. *) open Printf open Virt_mem_gettext.Gettext open Virt_mem_utils open Virt_mem_mmap let usage = s_"NAME virt-dmesg - dmesg command for virtual machines SUMMARY virt-dmesg [-options] [domains] DESCRIPTION virt-dmesg prints the kernel messages for virtual machines running under libvirt. The output is similar to the ordinary dmesg command run inside the virtual machine." let verbose, images = Virt_mem.start usage let () = List.iter ( fun (name, arch, mem, lookup_ksym) -> try (* I don't know why but this symbol doesn't exist in 2.6.9 * even in kallsyms. Hence this won't work with that kernel. * It's possible we can fall back to memory scanning. XXX *) let log_buf = lookup_ksym "log_buf" in let log_buf = follow_pointer mem log_buf in let log_buf_len = lookup_ksym "log_buf_len" in let log_buf_len = Int64.of_int32 (get_C_int mem log_buf_len) in (* let log_start = lookup_ksym "log_start" in let log_start = get_C_long mem log_start in *) let log_end = lookup_ksym "log_end" in let log_end = get_C_long mem log_end in (* let con_start = lookup_ksym "con_start" in let con_start = get_C_long mem con_start in *) let logged_chars = lookup_ksym "logged_chars" in let logged_chars = get_C_long mem logged_chars in (* This is basically the same algorithm from printk.c:do_syslog * type=3, translated into OCaml. Unlike the kernel version * however we don't copy the buffer backwards. *) let get_log_buf idx = let addr = log_buf +^ (idx &^ (log_buf_len -^ 1L)) in Char.chr (get_byte mem addr) in let count = log_buf_len in let count = if count > logged_chars then logged_chars else count in let limit = log_end in let rec loop i = if i >= 0L then ( let j = limit-^1L-^i in if j +^ log_buf_len >= log_end then ( let c = get_log_buf j in printf "%c" c; loop (i-^1L) ) ) in loop (count-^1L) with Not_found -> eprintf (f_"%s: could not find kernel log buffer in kernel image\n") name ) images