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/*
* Copyright (c) 2004 Marcel Moolenaar
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");
#include <sys/param.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/ioctl.h>
#include <sys/resource.h>
#include <sys/select.h>
#include <sys/time.h>
#include <sys/wait.h>
#include <errno.h>
#include <err.h>
#include <inttypes.h>
#include <kvm.h>
#include <limits.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
/* libgdb stuff. */
#include <defs.h>
#include <frame.h>
#include <frame-unwind.h>
#include <inferior.h>
#include <interps.h>
#include <cli-out.h>
#include <main.h>
#include <objfiles.h>
#include <target.h>
#include <top.h>
#include <ui-file.h>
#include <bfd.h>
#include <gdbcore.h>
#include <wrapper.h>
extern frame_unwind_sniffer_ftype *kgdb_sniffer_kluge;
#include "kgdb.h"
static int dumpnr;
static int quiet;
static int verbose;
static char crashdir[PATH_MAX];
static char *kernel;
static char *remote;
static char *vmcore;
static struct ui_file *parse_gdberr;
static void (*kgdb_new_objfile_chain)(struct objfile * objfile);
static void
usage(void)
{
fprintf(stderr,
"usage: %s [-afqv] [-d crashdir] [-c core | -n dumpnr | -r device]\n"
"\t[kernel [core]]\n", getprogname());
exit(1);
}
static void
kernel_from_dumpnr(int nr)
{
char path[PATH_MAX];
FILE *info;
char *s;
struct stat st;
int l;
/*
* If there's a kernel image right here in the crash directory, then
* use it. The kernel image is either called kernel.<nr> or is in a
* subdirectory kernel.<nr> and called kernel. The latter allows us
* to collect the modules in the same place.
*/
snprintf(path, sizeof(path), "%s/kernel.%d", crashdir, nr);
if (stat(path, &st) == 0) {
if (S_ISREG(st.st_mode)) {
kernel = strdup(path);
return;
}
if (S_ISDIR(st.st_mode)) {
snprintf(path, sizeof(path), "%s/kernel.%d/kernel",
crashdir, nr);
if (stat(path, &st) == 0 && S_ISREG(st.st_mode)) {
kernel = strdup(path);
return;
}
}
}
/*
* No kernel image here. Parse the dump header. The kernel object
* directory can be found there and we probably have the kernel
* image still in it. The object directory may also have a kernel
* with debugging info (called kernel.debug). If we have a debug
* kernel, use it.
*/
snprintf(path, sizeof(path), "%s/info.%d", crashdir, nr);
info = fopen(path, "r");
if (info == NULL) {
warn("%s", path);
return;
}
while (fgets(path, sizeof(path), info) != NULL) {
l = strlen(path);
if (l > 0 && path[l - 1] == '\n')
path[--l] = '\0';
if (strncmp(path, " ", 4) == 0) {
s = strchr(path, ':');
s = (s == NULL) ? path + 4 : s + 1;
l = snprintf(path, sizeof(path), "%s/kernel.debug", s);
if (stat(path, &st) == -1 || !S_ISREG(st.st_mode)) {
path[l - 6] = '\0';
if (stat(path, &st) == -1 ||
!S_ISREG(st.st_mode))
break;
}
kernel = strdup(path);
break;
}
}
fclose(info);
}
static void
kgdb_new_objfile(struct objfile *objfile)
{
static int once = 1;
kld_new_objfile(objfile);
kgdb_trgt_new_objfile(objfile);
if (kgdb_new_objfile_chain != NULL)
kgdb_new_objfile_chain(objfile);
if (once && objfile != NULL && objfile == symfile_objfile) {
/*
* The initial kernel has just been loaded. Start the
* remote target if we have one.
*/
once = 0;
if (remote != NULL)
push_remote_target (remote, 0);
}
}
/*
* Parse an expression and return its value. If 'quiet' is true, then
* any error messages from the parser are masked.
*/
CORE_ADDR
kgdb_parse_1(const char *exp, int quiet)
{
struct ui_file *old_stderr;
struct cleanup *old_chain;
struct expression *expr;
struct value *val;
char *s;
CORE_ADDR n;
old_stderr = gdb_stderr;
if (quiet)
gdb_stderr = parse_gdberr;
n = 0;
s = xstrdup(exp);
old_chain = make_cleanup(xfree, s);
if (gdb_parse_exp_1(&s, NULL, 0, &expr) && *s == '\0') {
make_cleanup(free_current_contents, &expr);
if (gdb_evaluate_expression(expr, &val))
n = value_as_address(val);
}
do_cleanups(old_chain);
gdb_stderr = old_stderr;
return (n);
}
#define MSGBUF_SEQ_TO_POS(size, seq) ((seq) % (size))
void
kgdb_dmesg(void)
{
CORE_ADDR bufp;
int size, rseq, wseq;
char c;
/*
* Display the unread portion of the message buffer. This gives the
* user a some initial data to work from.
*/
if (quiet)
return;
bufp = kgdb_parse("msgbufp->msg_ptr");
size = (int)kgdb_parse("msgbufp->msg_size");
if (bufp == 0 || size == 0)
return;
rseq = (int)kgdb_parse("msgbufp->msg_rseq");
wseq = (int)kgdb_parse("msgbufp->msg_wseq");
rseq = MSGBUF_SEQ_TO_POS(size, rseq);
wseq = MSGBUF_SEQ_TO_POS(size, wseq);
if (rseq == wseq)
return;
printf("\nUnread portion of the kernel message buffer:\n");
while (rseq < wseq) {
read_memory(bufp + rseq, &c, 1);
putchar(c);
rseq++;
if (rseq == size)
rseq = 0;
}
if (c != '\n')
putchar('\n');
putchar('\n');
}
static void
kgdb_init(char *argv0 __unused)
{
parse_gdberr = mem_fileopen();
set_prompt("(kgdb) ");
initialize_kgdb_target();
initialize_kld_target();
kgdb_new_objfile_chain = target_new_objfile_hook;
target_new_objfile_hook = kgdb_new_objfile;
}
/*
* Remote targets can support any number of syntaxes and we want to
* support them all with one addition: we support specifying a device
* node for a serial device without the "/dev/" prefix.
*
* What we do is to stat(2) the existing remote target first. If that
* fails, we try it with "/dev/" prepended. If that succeeds we use
* the resulting path, otherwise we use the original target. If
* either stat(2) succeeds make sure the file is either a character
* device or a FIFO.
*/
static void
verify_remote(void)
{
char path[PATH_MAX];
struct stat st;
if (stat(remote, &st) != 0) {
snprintf(path, sizeof(path), "/dev/%s", remote);
if (stat(path, &st) != 0)
return;
free(remote);
remote = strdup(path);
}
if (!S_ISCHR(st.st_mode) && !S_ISFIFO(st.st_mode))
errx(1, "%s: not a special file, FIFO or socket", remote);
}
static void
add_arg(struct captured_main_args *args, char *arg)
{
args->argc++;
args->argv = reallocf(args->argv, (args->argc + 1) * sizeof(char *));
if (args->argv == NULL)
err(1, "Out of memory building argument list");
args->argv[args->argc] = arg;
}
int
main(int argc, char *argv[])
{
char path[PATH_MAX];
struct stat st;
struct captured_main_args args;
char *s;
int a, ch;
dumpnr = -1;
strlcpy(crashdir, "/var/crash", sizeof(crashdir));
s = getenv("KGDB_CRASH_DIR");
if (s != NULL)
strlcpy(crashdir, s, sizeof(crashdir));
/* Convert long options into short options. */
for (a = 1; a < argc; a++) {
s = argv[a];
if (s[0] == '-') {
s++;
/* Long options take either 1 or 2 dashes. */
if (s[0] == '-')
s++;
if (strcmp(s, "quiet") == 0)
argv[a] = "-q";
else if (strcmp(s, "fullname") == 0)
argv[a] = "-f";
}
}
quiet = 0;
memset (&args, 0, sizeof args);
args.use_windows = 0;
args.interpreter_p = INTERP_CONSOLE;
args.argv = malloc(sizeof(char *));
args.argv[0] = argv[0];
while ((ch = getopt(argc, argv, "ac:d:fn:qr:vw")) != -1) {
switch (ch) {
case 'a':
annotation_level++;
break;
case 'c': /* use given core file. */
if (vmcore != NULL) {
warnx("option %c: can only be specified once",
optopt);
usage();
/* NOTREACHED */
}
vmcore = strdup(optarg);
break;
case 'd': /* lookup dumps in given directory. */
strlcpy(crashdir, optarg, sizeof(crashdir));
break;
case 'f':
annotation_level = 1;
break;
case 'n': /* use dump with given number. */
dumpnr = strtol(optarg, &s, 0);
if (dumpnr < 0 || *s != '\0') {
warnx("option %c: invalid kernel dump number",
optopt);
usage();
/* NOTREACHED */
}
break;
case 'q':
quiet = 1;
add_arg(&args, "-q");
break;
case 'r': /* use given device for remote session. */
if (remote != NULL) {
warnx("option %c: can only be specified once",
optopt);
usage();
/* NOTREACHED */
}
remote = strdup(optarg);
break;
case 'v': /* increase verbosity. */
verbose++;
break;
case 'w': /* core file is writeable. */
add_arg(&args, "--write");
break;
case '?':
default:
usage();
}
}
if (((vmcore != NULL) ? 1 : 0) + ((dumpnr >= 0) ? 1 : 0) +
((remote != NULL) ? 1 : 0) > 1) {
warnx("options -c, -n and -r are mutually exclusive");
usage();
/* NOTREACHED */
}
if (verbose > 1)
warnx("using %s as the crash directory", crashdir);
if (argc > optind)
kernel = strdup(argv[optind++]);
if (argc > optind && (dumpnr >= 0 || remote != NULL)) {
warnx("options -n and -r do not take a core file. Ignored");
optind = argc;
}
if (dumpnr >= 0) {
snprintf(path, sizeof(path), "%s/vmcore.%d", crashdir, dumpnr);
if (stat(path, &st) == -1)
err(1, "%s", path);
if (!S_ISREG(st.st_mode))
errx(1, "%s: not a regular file", path);
vmcore = strdup(path);
} else if (remote != NULL) {
verify_remote();
} else if (argc > optind) {
if (vmcore == NULL)
vmcore = strdup(argv[optind++]);
if (argc > optind)
warnx("multiple core files specified. Ignored");
} else if (vmcore == NULL && kernel == NULL) {
vmcore = strdup(_PATH_MEM);
kernel = strdup(getbootfile());
}
if (verbose) {
if (vmcore != NULL)
warnx("core file: %s", vmcore);
if (remote != NULL)
warnx("device file: %s", remote);
if (kernel != NULL)
warnx("kernel image: %s", kernel);
}
/* A remote target requires an explicit kernel argument. */
if (remote != NULL && kernel == NULL) {
warnx("remote debugging requires a kernel");
usage();
/* NOTREACHED */
}
/* If we don't have a kernel image yet, try to find one. */
if (kernel == NULL) {
if (dumpnr >= 0)
kernel_from_dumpnr(dumpnr);
if (kernel == NULL)
errx(1, "couldn't find a suitable kernel image");
if (verbose)
warnx("kernel image: %s", kernel);
}
add_arg(&args, kernel);
if (vmcore != NULL)
add_arg(&args, vmcore);
/* The libgdb code uses optind too. Reset it... */
optind = 0;
/* Terminate argv list. */
add_arg(&args, NULL);
init_ui_hook = kgdb_init;
kgdb_sniffer_kluge = kgdb_trgt_trapframe_sniffer;
return (gdb_main(&args));
}
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