aboutsummaryrefslogtreecommitdiff
path: root/libbb/find_pid_by_name.c
blob: a648137e14e19376493a28a3172fd06e1c39b8cb (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
/* vi: set sw=4 ts=4: */
/*
 * Utility routines.
 *
 * Copyright (C) 1999,2000,2001 by Erik Andersen <andersee@debian.org>
 *
 * 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 <ctype.h>
#include <string.h>
#include <stdlib.h>
#include "libbb.h"

#define READ_BUF_SIZE	50


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

/* find_pid_by_name()
 *  
 *  This finds the pid of the specified process,
 *  by using the /dev/ps device driver.
 *
 *  Returns a list of all matching PIDs
 */
extern long* find_pid_by_name( const char* pidName)
{
	int fd, i, j;
	char device[] = "/dev/ps";
	pid_t num_pids;
	pid_t* pid_array = NULL;
	long* pidList=NULL;

	/* 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");

	/* Now search for a match */
	for (i=1, j=0; i<pid_array[0] ; i++) {
		char* p;
		struct pid_info info;

	    info.pid = pid_array[i];
	    if (ioctl (fd, DEVPS_GET_PID_INFO, &info)<0)
			perror_msg_and_die("\nDEVPS_GET_PID_INFO");

		/* Make sure we only match on the process name */
		p=info.command_line+1;
		while ((*p != 0) && !isspace(*(p)) && (*(p-1) != '\\')) { 
			(p)++;
		}
		if (isspace(*(p)))
				*p='\0';

		if ((strstr(info.command_line, pidName) != NULL)
				&& (strlen(pidName) == strlen(info.command_line))) {
			pidList=xrealloc( pidList, sizeof(long) * (j+2));
			pidList[j++]=info.pid;
		}
	}
	if (pidList) {
		pidList[j]=0;
	} else {
		pidList=xrealloc( pidList, sizeof(long));
		pidList[0]=-1;
	}

	/* Free memory */
	free( pid_array);

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

	return pidList;
}

#else		/* CONFIG_FEATURE_USE_DEVPS_PATCH */

/* find_pid_by_name()
 *  
 *  Modified by Vladimir Oleynik for use with libbb/procps.c
 *  This finds the pid of the specified process.
 *  Currently, it's implemented by rummaging through 
 *  the proc filesystem.
 *
 *  Returns a list of all matching PIDs
 */
extern long* find_pid_by_name( const char* pidName)
{
	long* pidList;
	int i=0;
	procps_status_t * p;

	pidList = xmalloc(sizeof(long));
	while ((p = procps_scan(0)) != 0) {
		if (strcmp(p->short_cmd, pidName) == 0) {
			pidList=xrealloc( pidList, sizeof(long) * (i+2));
			pidList[i++]=p->pid;
		}
	}

	pidList[i] = i==0 ? -1 : 0;
	return pidList;
}
#endif							/* CONFIG_FEATURE_USE_DEVPS_PATCH */

/* END CODE */
/*
Local Variables:
c-file-style: "linux"
c-basic-offset: 4
tab-width: 4
End:
*/