aboutsummaryrefslogtreecommitdiffstats
path: root/arch/um/os-Linux/process.c
blob: ba9ca1cc790a52d6f7940fc9515d77e471f39328 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
/* 
 * Copyright (C) 2002 Jeff Dike (jdike@addtoit.com)
 * Licensed under the GPL
 */

#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <signal.h>
#include <linux/unistd.h>
#include <sys/mman.h>
#include <sys/wait.h>
#include "ptrace_user.h"
#include "os.h"
#include "user.h"
#include "user_util.h"

#define ARBITRARY_ADDR -1
#define FAILURE_PID    -1

#define STAT_PATH_LEN sizeof("/proc/#######/stat\0")
#define COMM_SCANF "%*[^)])"

unsigned long os_process_pc(int pid)
{
	char proc_stat[STAT_PATH_LEN], buf[256];
	unsigned long pc;
	int fd, err;

	sprintf(proc_stat, "/proc/%d/stat", pid);
	fd = os_open_file(proc_stat, of_read(OPENFLAGS()), 0);
	if(fd < 0){
		printk("os_process_pc - couldn't open '%s', err = %d\n",
		       proc_stat, -fd);
		return(ARBITRARY_ADDR);
	}
	err = os_read_file(fd, buf, sizeof(buf));
	if(err < 0){
		printk("os_process_pc - couldn't read '%s', err = %d\n",
		       proc_stat, -err);
		os_close_file(fd);
		return(ARBITRARY_ADDR);
	}
	os_close_file(fd);
	pc = ARBITRARY_ADDR;
	if(sscanf(buf, "%*d " COMM_SCANF " %*c %*d %*d %*d %*d %*d %*d %*d "
		  "%*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d %*d "
		  "%*d %*d %*d %*d %*d %lu", &pc) != 1){
		printk("os_process_pc - couldn't find pc in '%s'\n", buf);
	}
	return(pc);
}

int os_process_parent(int pid)
{
	char stat[STAT_PATH_LEN];
	char data[256];
	int parent, n, fd;

	if(pid == -1) return(-1);

	snprintf(stat, sizeof(stat), "/proc/%d/stat", pid);
	fd = os_open_file(stat, of_read(OPENFLAGS()), 0);
	if(fd < 0){
		printk("Couldn't open '%s', err = %d\n", stat, -fd);
		return(FAILURE_PID);
	}

	n = os_read_file(fd, data, sizeof(data));
	os_close_file(fd);

	if(n < 0){
		printk("Couldn't read '%s', err = %d\n", stat, -n);
		return(FAILURE_PID);
	}

	parent = FAILURE_PID;
	n = sscanf(data, "%*d " COMM_SCANF " %*c %d", &parent);
	if(n != 1)
		printk("Failed to scan '%s'\n", data);

	return(parent);
}

void os_stop_process(int pid)
{
	kill(pid, SIGSTOP);
}

void os_kill_process(int pid, int reap_child)
{
	kill(pid, SIGKILL);
	if(reap_child)
		CATCH_EINTR(waitpid(pid, NULL, 0));
		
}

/* Kill off a ptraced child by all means available.  kill it normally first,
 * then PTRACE_KILL it, then PTRACE_CONT it in case it's in a run state from
 * which it can't exit directly.
 */

void os_kill_ptraced_process(int pid, int reap_child)
{
	kill(pid, SIGKILL);
	ptrace(PTRACE_KILL, pid);
	ptrace(PTRACE_CONT, pid);
	if(reap_child)
		CATCH_EINTR(waitpid(pid, NULL, 0));
}

void os_usr1_process(int pid)
{
	kill(pid, SIGUSR1);
}

/*Don't use the glibc version, which caches the result in TLS. It misses some
 * syscalls, and also breaks with clone(), which does not unshare the TLS.*/
inline _syscall0(pid_t, getpid)

int os_getpid(void)
{
	return(getpid());
}

int os_map_memory(void *virt, int fd, unsigned long long off, unsigned long len,
		  int r, int w, int x)
{
	void *loc;
	int prot;

	prot = (r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
		(x ? PROT_EXEC : 0);

	loc = mmap64((void *) virt, len, prot, MAP_SHARED | MAP_FIXED,
		     fd, off);
	if(loc == MAP_FAILED)
		return(-errno);
	return(0);
}

int os_protect_memory(void *addr, unsigned long len, int r, int w, int x)
{
        int prot = ((r ? PROT_READ : 0) | (w ? PROT_WRITE : 0) | 
		    (x ? PROT_EXEC : 0));

        if(mprotect(addr, len, prot) < 0)
		return(-errno);
        return(0);
}

int os_unmap_memory(void *addr, int len)
{
        int err;

        err = munmap(addr, len);
	if(err < 0)
		return(-errno);
        return(0);
}

/*
 * 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:
 */