1 /* libguestfs - the guestfsd daemon
2 * Copyright (C) 2009 Red Hat Inc.
4 * This program is free software; you can redistribute it and/or modify
5 * it under the terms of the GNU General Public License as published by
6 * the Free Software Foundation; either version 2 of the License, or
7 * (at your option) any later version.
9 * This program is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 * GNU General Public License for more details.
14 * You should have received a copy of the GNU General Public License
15 * along with this program; if not, write to the Free Software
16 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 #include <sys/types.h>
29 #include "../src/guestfs_protocol.h"
33 /* This command exposes debugging information, internals and
34 * status. There is no comprehensive documentation for this
35 * command. You have to look at the source code in this file
36 * to find out what you can do.
38 * Commands always output a freeform string.
41 #if ENABLE_DEBUG_COMMAND
44 char * (*f) (const char *subcmd, int argc, char *const *const argv);
47 static char *debug_help (const char *subcmd, int argc, char *const *const argv);
48 static char *debug_env (const char *subcmd, int argc, char *const *const argv);
49 static char *debug_fds (const char *subcmd, int argc, char *const *const argv);
50 static char *debug_segv (const char *subcmd, int argc, char *const *const argv);
51 static char *debug_sh (const char *subcmd, int argc, char *const *const argv);
53 static struct cmd cmds[] = {
54 { "help", debug_help },
57 { "segv", debug_segv },
63 #if ! ENABLE_DEBUG_COMMAND
64 # define MAYBE_UNUSED ATTRIBUTE_UNUSED
66 # define MAYBE_UNUSED /* empty */
70 do_debug (const char *subcmd MAYBE_UNUSED, char **argv MAYBE_UNUSED)
72 #if ENABLE_DEBUG_COMMAND
75 for (i = argc = 0; argv[i] != NULL; ++i)
78 for (i = 0; cmds[i].cmd != NULL; ++i) {
79 if (strcasecmp (subcmd, cmds[i].cmd) == 0)
80 return cmds[i].f (subcmd, argc, argv);
83 reply_with_error ("use 'debug help' to list the supported commands");
86 reply_with_error ("guestfsd was not configured with --enable-debug-command");
91 #if ENABLE_DEBUG_COMMAND
93 debug_help (const char *subcmd, int argc, char *const *const argv)
98 r = strdup ("Commands supported:");
100 reply_with_perror ("strdup");
105 for (i = 0; cmds[i].cmd != NULL; ++i) {
106 len += strlen (cmds[i].cmd) + 1; /* space + new command */
107 p = realloc (r, len + 1); /* +1 for the final NUL */
109 reply_with_perror ("realloc");
116 strcat (r, cmds[i].cmd);
124 debug_fds (const char *subcmd, int argc, char *const *const argv)
132 char fname[256], link[256];
135 fp = open_memstream (&out, &size);
137 reply_with_perror ("open_memstream");
141 dir = opendir ("/proc/self/fd");
143 reply_with_perror ("opendir: /proc/self/fd");
148 while ((d = readdir (dir)) != NULL) {
149 if (strcmp (d->d_name, ".") == 0 || strcmp (d->d_name, "..") == 0)
152 snprintf (fname, sizeof fname, "/proc/self/fd/%s", d->d_name);
154 r = lstat (fname, &statbuf);
156 reply_with_perror ("stat: %s", fname);
163 if (S_ISLNK (statbuf.st_mode)) {
164 r = readlink (fname, link, sizeof link - 1);
166 reply_with_perror ("readline: %s", fname);
174 fprintf (fp, "%2s %s\n", d->d_name, link);
176 fprintf (fp, "%2s 0%o\n", d->d_name, statbuf.st_mode);
181 if (closedir (dir) == -1) {
182 reply_with_perror ("closedir");
190 /* Force a segfault in the daemon. */
192 debug_segv (const char *subcmd, int argc, char *const *const argv)
198 /* Run an arbitrary shell command using /bin/sh from the appliance.
200 * Note this is somewhat different from the ordinary guestfs_sh command
201 * because it's not using the guest shell, and is not chrooted.
203 * Also we ignore any errors and you can see the full output if you
204 * add 2>&1 to the end of the command string.
207 debug_sh (const char *subcmd, int argc, char *const *const argv)
214 reply_with_error ("debug: sh: expecting a command to run");
218 /* guestfish splits the parameter(s) into a list of strings,
219 * and we have to reassemble them here. Not ideal. XXX
221 for (i = len = 0; i < argc; ++i)
222 len += strlen (argv[i]) + 1;
225 reply_with_perror ("malloc");
228 for (i = j = 0; i < argc; ++i) {
229 len = strlen (argv[i]);
230 memcpy (&cmd[j], argv[i], len);
237 command (&out, NULL, "/bin/sh", "-c", cmd, NULL);
242 /* Print the environment that commands get (by running external printenv). */
244 debug_env (const char *subcmd, int argc, char *const *const argv)
249 r = command (&out, &err, "printenv", NULL);
251 reply_with_error ("printenv: %s", err);
262 #endif /* ENABLE_DEBUG_COMMAND */