/*
* Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
* Licensed under the GPL
*/
#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include <signal.h>
#include <sys/types.h>
#include "ptrace_user.h"
#include "uml-config.h"
#include "kern_constants.h"
#include "chan_user.h"
#include "init.h"
#include "user.h"
#include "debug.h"
#include "kern_util.h"
#include "tt.h"
#include "sysdep/thread.h"
#include "os.h"
extern int debugger_pid;
extern int debugger_fd;
extern int debugger_parent;
int detach(int pid, int sig)
{
return(ptrace(PTRACE_DETACH, pid, 0, sig));
}
int attach(int pid)
{
int err;
err = ptrace(PTRACE_ATTACH, pid, 0, 0);
if(err < 0) return(-errno);
else return(err);
}
int cont(int pid)
{
return(ptrace(PTRACE_CONT, pid, 0, 0));
}
#ifdef UML_CONFIG_PT_PROXY
int debugger_signal(int status, pid_t pid)
{
return(debugger_proxy(status, pid));
}
void child_signal(pid_t pid, int status)
{
child_proxy(pid, status);
}
static void gdb_announce(char *dev_name, int dev)
{
printf("gdb assigned device '%s'\n", dev_name);
}
static struct chan_opts opts = {
.announce = gdb_announce,
.xterm_title = "UML kernel debugger",
.raw = 0,
.tramp_stack = 0,
.in_kernel = 0,
};
/* Accessed by the tracing thread, which automatically serializes access */
static void *xterm_data;
static int xterm_fd;
extern void *xterm_init(char *, int, struct chan_opts *);
extern int xterm_open(int, int, int, void *, char **);
extern void xterm_close(int, void *);
int open_gdb_chan(void)
{
char stack[UM_KERN_PAGE_SIZE], *dummy;
opts.tramp_stack = (unsigned long) stack;
xterm_data = xterm_init("", 0, &opts);
xterm_fd = xterm_open(1, 1, 1, xterm_data, &dummy);
return(xterm_fd);
}
static void exit_debugger_cb(void *unused)
{
if(debugger_pid != -1){
if(gdb_pid != -1){
fake_child_exit();
gdb_pid = -1;
}
else kill_child_dead(debugger_pid);
debugger_pid = -1;
if(debugger_parent != -1)
detach(debugger_parent, SIGINT);
}
if(xterm_data != NULL) xterm_close(xterm_fd, xterm_data);
}
static void exit_debugger(void)
{
initial_thread_cb(exit_debugger_cb, NULL);
}
__uml_exitcall(exit_debugger);
struct gdb_data {
char *str;
int err;
};
extern char *linux_prog;
static void config_gdb_cb(void *arg)
{
struct gdb_data *data = arg;
void *task;
int pid;
data->err = -1;
if(debugger_pid != -1) exit_debugger_cb(NULL);
if(!strncmp(data->str, "pid,", strlen("pid,"))){
data->str += strlen("pid,");
pid = strtoul(data->str, NULL, 0);
task = cpu_tasks[0].task;
debugger_pid = attach_debugger(TASK_EXTERN_PID(task), pid, 0);
if(debugger_pid != -1){
data->err = 0;
gdb_pid = pid;
}
return;
}
data->err = 0;
debugger_pid = start_debugger(linux_prog, 0, 0, &debugger_fd);
init_proxy(debugger_pid, 0, 0);
}
int gdb_config(char *str, char **error_out)
{
struct gdb_data data;
if(*str++ != '=') return(-1);
data.str = str;
initial_thread_cb(config_gdb_cb, &data);
return(data.err);
}
void remove_gdb_cb(void *unused)
{
exit_debugger_cb(NULL);
}
int gdb_remove(int unused, char **error_out)
{
initial_thread_cb(remove_gdb_cb, NULL);
return 0;
}
void signal_usr1(int sig)
{
if(debugger_pid != -1){
printf("The debugger is already running\n");
return;
}
debugger_pid = start_debugger(linux_prog, 0, 0, &debugger_fd);
init_proxy(debugger_pid, 0, 0);
}
int init_ptrace_proxy(int idle_pid, int startup, int stop)
{
int pid, status;
pid = start_debugger(linux_prog, startup, stop, &debugger_fd);
status = wait_for_stop(idle_pid, SIGSTOP, PTRACE_CONT, NULL);
if(pid < 0){
cont(idle_pid);
return(-1);
}
init_proxy(pid, 1, status);
return(pid);
}
int attach_debugger(int idle_pid, int pid, int stop)
{
int status = 0, err;
err = attach(pid);
if(err < 0){
printf("Failed to attach pid %d, errno = %d\n", pid, -err);
return(-1);
}
if(stop) status = wait_for_stop(idle_pid, SIGSTOP, PTRACE_CONT, NULL);
init_proxy(pid, 1, status);
return(pid);
}
#ifdef notdef /* Put this back in when it does something useful */
static int __init uml_gdb_init_setup(char *line, int *add)
{
gdb_init = uml_strdup(line);
return 0;
}
__uml_setup("gdb=", uml_gdb_init_setup,
"gdb=<channel description>\n\n"
);
#endif
static int __init uml_gdb_pid_setup(char *line, int *add)
{
gdb_pid = strtoul(line, NULL, 0);
*add = 0;
return 0;
}
__uml_setup("gdb-pid=", uml_gdb_pid_setup,
"gdb-pid=<pid>\n"
" gdb-pid is used to attach an external debugger to UML. This may be\n"
" an already-running gdb or a debugger-like process like strace.\n\n"
);
#else
int debugger_signal(int status, pid_t pid){ return(0); }
void child_signal(pid_t pid, int status){ }
int init_ptrace_proxy(int idle_pid, int startup, int stop)
{
printf("debug requested when CONFIG_PT_PROXY is off\n");
kill_child_dead(idle_pid);
exit(1);
}
void signal_usr1(int sig)
{
printf("debug requested when CONFIG_PT_PROXY is off\n");
}
int attach_debugger(int idle_pid, int pid, int stop)
{
printf("attach_debugger called when CONFIG_PT_PROXY "
"is off\n");
return(-1);
}
int config_gdb(char *str)
{
return(-1);
}
int remove_gdb(void)
{
return(-1);
}
int init_parent_proxy(int pid)
{
return(-1);
}
void debugger_parent_signal(int status, int pid)
{
}
#endif
/*
* Overrides for Emacs so that we follow Linus's tabbing style.
* Emacs will notice this stuff at the end of the file and automatically
* adjust the settings for this buffer only. This must remain at the end
* of the file.
* ---------------------------------------------------------------------------
* Local variables:
* c-file-style: "linux"
* End:
*/
