From 920167791708b2e5cfd8dad925be0d6d7426a429 Mon Sep 17 00:00:00 2001 From: Pau Espin Pedrol Date: Mon, 18 Mar 2019 17:24:34 +0100 Subject: [PATCH] Add vty option to print output of shell cmd on every poll step Change-Id: I005773b75f81fa5f6c90f53af508fc6debea208b --- doc/examples/osmo-sysmon.cfg | 1 + src/Makefile.am | 1 + src/osysmon.h | 7 +- src/osysmon_main.c | 3 + src/osysmon_shellcmd.c | 174 +++++++++++++++++++++++++++++++++++ 5 files changed, 185 insertions(+), 1 deletion(-) create mode 100644 src/osysmon_shellcmd.c diff --git a/doc/examples/osmo-sysmon.cfg b/doc/examples/osmo-sysmon.cfg index f944f72..22c27cb 100644 --- a/doc/examples/osmo-sysmon.cfg +++ b/doc/examples/osmo-sysmon.cfg @@ -14,3 +14,4 @@ netdev tun0 ping example.com openvpn 127.0.0.1 1234 file os-image /etc/image-datetime +shellcmd kernel uname -a diff --git a/src/Makefile.am b/src/Makefile.am index f9b79f2..a4663fd 100644 --- a/src/Makefile.am +++ b/src/Makefile.am @@ -42,6 +42,7 @@ osmo_sysmon_SOURCES = \ osysmon_file.c \ osysmon_ping.c \ osysmon_openvpn.c \ + osysmon_shellcmd.c \ osysmon_main.c \ $(NULL) diff --git a/src/osysmon.h b/src/osysmon.h index 2f82c47..36cd608 100644 --- a/src/osysmon.h +++ b/src/osysmon.h @@ -13,6 +13,8 @@ struct ping_state; struct osysmon_state { struct rtnl_client_state *rcs; + /* list of 'struct osysmon_cmd' */ + struct llist_head shellcmds; /* list of 'struct ctrl client' */ struct llist_head ctrl_clients; /* list of 'struct openvpn_client' */ @@ -21,6 +23,7 @@ struct osysmon_state { struct llist_head netdevs; /* list of 'struct osysmon_file' */ struct llist_head files; + /* list of ping contexts */ struct ping_state *pings; }; @@ -36,7 +39,6 @@ enum osysmon_vty_node { PING_NODE, }; - int osysmon_ctrl_go_parent(struct vty *vty); int osysmon_ctrl_init(); int osysmon_ctrl_poll(struct value_node *parent); @@ -56,3 +58,6 @@ int osysmon_openvpn_poll(struct value_node *parent); int osysmon_file_init(); int osysmon_file_poll(struct value_node *parent); + +int osysmon_shellcmd_init(); +int osysmon_shellcmd_poll(struct value_node *parent); diff --git a/src/osysmon_main.c b/src/osysmon_main.c index 1ba3753..fb01f5e 100644 --- a/src/osysmon_main.c +++ b/src/osysmon_main.c @@ -207,6 +207,7 @@ static void print_nodes(__attribute__((unused)) void *data) osysmon_ping_poll(root); osysmon_file_poll(root); + osysmon_shellcmd_poll(root); display_update(root); value_node_del(root); @@ -221,6 +222,7 @@ int main(int argc, char **argv) osmo_init_logging2(NULL, &log_info); g_oss = talloc_zero(NULL, struct osysmon_state); + INIT_LLIST_HEAD(&g_oss->shellcmds); INIT_LLIST_HEAD(&g_oss->ctrl_clients); INIT_LLIST_HEAD(&g_oss->openvpn_clients); INIT_LLIST_HEAD(&g_oss->netdevs); @@ -229,6 +231,7 @@ int main(int argc, char **argv) vty_init(&vty_info); handle_options(argc, argv); osysmon_sysinfo_init(); + osysmon_shellcmd_init(); osysmon_ctrl_init(); osysmon_openvpn_init(); osysmon_rtnl_init(); diff --git a/src/osysmon_shellcmd.c b/src/osysmon_shellcmd.c new file mode 100644 index 0000000..347b982 --- /dev/null +++ b/src/osysmon_shellcmd.c @@ -0,0 +1,174 @@ +/* Simple Osmocom System Monitor (osysmon): Support for monitoring through shell commands */ + +/* (C) 2019 by sysmocom - s.f.m.c. GmbH + * All Rights Reserved. + * Author: Pau Espin Pedrol + * + * SPDX-License-Identifier: GPL-2.0+ + * + * 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., 51 Franklin Street, Fifth Floor, Boston, + * MA 02110-1301, USA. + */ + +#include +#include +#include +#include + +#include +#include + +#include "osysmon.h" +#include "value_node.h" + +/*********************************************************************** + * Data model + ***********************************************************************/ + +struct osysmon_shellcmd { + struct llist_head list; + struct { + const char *name; + const char *cmd; + } cfg; +}; + +static struct osysmon_shellcmd *osysmon_shellcmd_find(const char *name) +{ + struct osysmon_shellcmd *oc; + + llist_for_each_entry(oc, &g_oss->shellcmds, list) { + if (!strcmp(oc->cfg.name, name)) + return oc; + } + return NULL; +} + +static struct osysmon_shellcmd *osysmon_shellcmd_add(const char *name, const char *cmd) +{ + struct osysmon_shellcmd *oc; + + if (osysmon_shellcmd_find(name)) + return NULL; + + oc = talloc_zero(g_oss, struct osysmon_shellcmd); + OSMO_ASSERT(oc); + oc->cfg.name = talloc_strdup(oc, name); + oc->cfg.cmd = talloc_strdup(oc, cmd); + llist_add_tail(&oc->list, &g_oss->shellcmds); + return oc; +} + +static void osysmon_shellcmd_destroy(struct osysmon_shellcmd *oc) +{ + llist_del(&oc->list); + talloc_free(oc); +} + +static void osysmon_shellcmd_run(struct osysmon_shellcmd *oc, struct value_node *parent) +{ + char buf[512]; + FILE *f; + char *p = buf; + long offset = 0; + + f = popen(oc->cfg.cmd, "r"); + if (!f) { + snprintf(buf, sizeof(buf), "", errno); + value_node_add(parent, oc->cfg.name, buf); + return; + } + + while ((offset = fread(p, 1, sizeof(buf) - 1 - (p - buf), f)) != 0) { + p += offset; + *p = '\0'; + } + + pclose(f); + + if (buf != p) { + if (*(p - 1) == '\n') /* Remove final new line if exists */ + *(p - 1) = '\0'; + value_node_add(parent, oc->cfg.name, buf); + } else { + value_node_add(parent, oc->cfg.name, ""); + } +} + +/*********************************************************************** + * VTY + ***********************************************************************/ + +#define CMD_STR "Configure a shell command to be executed\n" +DEFUN(cfg_shellcmd, cfg_shellcmd_cmd, + "shellcmd NAME .TEXT", + CMD_STR "Name of this shell command snippet\n" "Command to run\n") +{ + struct osysmon_shellcmd *oc; + char *concat = argv_concat(argv, argc, 1); + oc = osysmon_shellcmd_add(argv[0], concat); + talloc_free(concat); + if (!oc) { + vty_out(vty, "Couldn't add shell cmd, maybe it exists?%s", VTY_NEWLINE); + return CMD_WARNING; + } + return CMD_SUCCESS; +} + +DEFUN(cfg_no_shellcmd, cfg_no_shellcmd_cmd, + "no shellcmd NAME", + NO_STR CMD_STR "Name of this shell command snippet\n") +{ + struct osysmon_shellcmd *oc; + oc = osysmon_shellcmd_find(argv[0]); + if (!oc) { + vty_out(vty, "Cannot find shell cmd for '%s'%s", argv[0], VTY_NEWLINE); + return CMD_WARNING; + } + osysmon_shellcmd_destroy(oc); + return CMD_SUCCESS; +} + + +static void osysmon_shellcmd_vty_init(void) +{ + install_element(CONFIG_NODE, &cfg_shellcmd_cmd); + install_element(CONFIG_NODE, &cfg_no_shellcmd_cmd); +} + +/*********************************************************************** + * Runtime Code + ***********************************************************************/ + +/* called once on startup before config file parsing */ +int osysmon_shellcmd_init() +{ + osysmon_shellcmd_vty_init(); + return 0; +} + +/* called periodically */ +int osysmon_shellcmd_poll(struct value_node *parent) +{ + struct value_node *vn_file; + struct osysmon_shellcmd *oc; + + vn_file = value_node_add(parent, "shellcmd", NULL); + + llist_for_each_entry(oc, &g_oss->shellcmds, list) + osysmon_shellcmd_run(oc, vn_file); + + return 0; +}