summaryrefslogtreecommitdiffhomepage
path: root/procps/ps.c
blob: 7afb0091f67f18e8c9ec53e8463885c6062a0284 (plain)
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
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
/* vi: set sw=4 ts=4: */
/*
 * Mini ps implementation(s) for busybox
 *
 * Copyright (C) 1999,2000,2001 by Lineo, inc.  
 * Written by Erik Andersen <andersen@lineo.com>, <andersee@debian.org>
 *
 *
 * This contains _two_ implementations of ps for Linux.  One uses the
 * traditional /proc virtual filesystem, and the other use the devps kernel
 * driver (written by Erik Andersen to avoid using /proc thereby saving 100k+).
 *
 *
 *
 * 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., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <ctype.h>
#include <string.h>
#include <sys/ioctl.h>
#include "busybox.h"

static const int TERMINAL_WIDTH = 79;      /* not 80 in case terminal has linefold bug */



#if ! defined BB_FEATURE_USE_DEVPS_PATCH

/* The following is the first ps implementation --
 * the one using the /proc virtual filesystem.
 */

typedef struct proc_s {
	char
	 cmd[16];					/* basename of executable file in call to exec(2) */
	int
	 ruid,						/* real only (sorry) */
	 pid,						/* process id */
	 ppid;						/* pid of parent process */
	char
	 state;						/* single-char code for process state (S=sleeping) */
} proc_t;



static int file2str(char *filename, char *ret, int cap)
{
	int fd, num_read;

	if ((fd = open(filename, O_RDONLY, 0)) == -1)
		return -1;
	if ((num_read = read(fd, ret, cap - 1)) <= 0)
		return -1;
	ret[num_read] = 0;
	close(fd);
	return num_read;
}


static void parse_proc_status(char *S, proc_t * P)
{
	char *tmp;

	memset(P->cmd, 0, sizeof P->cmd);
	sscanf(S, "Name:\t%15c", P->cmd);
	tmp = strchr(P->cmd, '\n');
	if (tmp)
		*tmp = '\0';
	tmp = strstr(S, "State");
	sscanf(tmp, "State:\t%c", &P->state);

	tmp = strstr(S, "Pid:");
	if (tmp)
		sscanf(tmp, "Pid:\t%d\n" "PPid:\t%d\n", &P->pid, &P->ppid);
	else
		error_msg("Internal error!");

	/* For busybox, ignoring effective, saved, etc. */
	tmp = strstr(S, "Uid:");
	if (tmp)
		sscanf(tmp, "Uid:\t%d", &P->ruid);
	else
		error_msg("Internal error!");


}

extern int ps_main(int argc, char **argv)
{
	proc_t p;
	DIR *dir;
	FILE *file;
	struct dirent *entry;
	char path[32], sbuf[512];
	char uidName[9];
	int len, i, c;
#ifdef BB_FEATURE_AUTOWIDTH
	struct winsize win = { 0, 0, 0, 0 };
	int terminal_width = TERMINAL_WIDTH;
#else
#define terminal_width  TERMINAL_WIDTH
#endif



	dir = opendir("/proc");
	if (!dir)
		error_msg_and_die("Can't open /proc");

#ifdef BB_FEATURE_AUTOWIDTH
		ioctl(fileno(stdout), TIOCGWINSZ, &win);
		if (win.ws_col > 0)
			terminal_width = win.ws_col - 1;
#endif

	printf("  PID  Uid     Stat Command\n");
	while ((entry = readdir(dir)) != NULL) {
		if (!isdigit(*entry->d_name))
			continue;
		sprintf(path, "/proc/%s/status", entry->d_name);
		if ((file2str(path, sbuf, sizeof sbuf)) != -1) {
			parse_proc_status(sbuf, &p);
		}

		/* Make some adjustments as needed */
		my_getpwuid(uidName, p.ruid);
		if (*uidName == '\0')
			sprintf(uidName, "%d", p.ruid);

		sprintf(path, "/proc/%s/cmdline", entry->d_name);
		file = fopen(path, "r");
		if (file == NULL)
			continue;
		i = 0;
		len = printf("%5d %-8s %c    ", p.pid, uidName, p.state);
		while (((c = getc(file)) != EOF) && (i < (terminal_width-len))) {
			i++;
			if (c == '\0')
				c = ' ';
			putc(c, stdout);
		}
		fclose(file);
		if (i == 0)
			printf("[%s]", p.cmd);
		putchar('\n');
	}
	closedir(dir);
	return EXIT_SUCCESS;
}


#else /* BB_FEATURE_USE_DEVPS_PATCH */


/* The following is the second ps implementation --
 * this one uses the nifty new devps kernel device.
 */

#include <linux/devps.h> /* For Erik's nifty devps device driver */


extern int ps_main(int argc, char **argv)
{
	char device[] = "/dev/ps";
	int i, j, len, fd;
	pid_t num_pids;
	pid_t* pid_array = NULL;
	struct pid_info info;
	char uidName[9];
#ifdef BB_FEATURE_AUTOWIDTH
	struct winsize win = { 0, 0, 0, 0 };
	int terminal_width = TERMINAL_WIDTH;
#else
#define terminal_width  TERMINAL_WIDTH
#endif

	if (argc > 1 && **(argv + 1) == '-') 
		show_usage();

	/* open device */ 
	fd = open(device, O_RDONLY);
	if (fd < 0) 
		perror_msg_and_die( "open failed for `%s'", device);

	/* Find out how many processes there are */
	if (ioctl (fd, DEVPS_GET_NUM_PIDS, &num_pids)<0) 
		perror_msg_and_die( "\nDEVPS_GET_PID_LIST");
	
	/* Allocate some memory -- grab a few extras just in case 
	 * some new processes start up while we wait. The kernel will
	 * just ignore any extras if we give it too many, and will trunc.
	 * the list if we give it too few.  */
	pid_array = (pid_t*) xcalloc( num_pids+10, sizeof(pid_t));
	pid_array[0] = num_pids+10;

	/* Now grab the pid list */
	if (ioctl (fd, DEVPS_GET_PID_LIST, pid_array)<0) 
		perror_msg_and_die("\nDEVPS_GET_PID_LIST");

#ifdef BB_FEATURE_AUTOWIDTH
		ioctl(fileno(stdout), TIOCGWINSZ, &win);
		if (win.ws_col > 0)
			terminal_width = win.ws_col - 1;
#endif

	/* Print up a ps listing */
	printf("  PID  Uid     Stat Command\n");

	for (i=1; i<pid_array[0] ; i++) {
	    info.pid = pid_array[i];

	    if (ioctl (fd, DEVPS_GET_PID_INFO, &info)<0)
			perror_msg_and_die("\nDEVPS_GET_PID_INFO");
	    
		/* Make some adjustments as needed */
		my_getpwuid(uidName, info.euid);
		if (*uidName == '\0')
			sprintf(uidName, "%ld", info.euid);

		len = printf("%5d %-8s %c    ", info.pid, uidName, info.state);

		if (strlen(info.command_line) > 1) {
			for( j=0; j<(sizeof(info.command_line)-1) && j < (terminal_width-len); j++) {
				if (*(info.command_line+j) == '\0' && *(info.command_line+j+1) != '\0') {
					*(info.command_line+j) = ' ';
				}
			}
			*(info.command_line+j) = '\0';
			puts(info.command_line);
		} else {
			printf("[%s]\n", info.name);
		}
	}

	/* Free memory */
	free( pid_array);

	/* close device */
	if (close (fd) != 0) 
		perror_msg_and_die("close failed for `%s'", device);
 
	exit (0);
}

#endif /* BB_FEATURE_USE_DEVPS_PATCH */