2ebe66e9db16ddab671d9cfafbab678133d246bb
[oweals/busybox.git] / libbb / procps.c
1 /* vi: set sw=4 ts=4: */
2 /*
3  * Utility routines.
4  *
5  * Copyright 1998 by Albert Cahalan; all rights reserved.
6  * Copyright (C) 2002 by Vladimir Oleynik <dzo@simtreas.ru>
7  * GNU Library General Public License Version 2, or any later version
8  *
9  */
10
11 #include <dirent.h>
12 #include <string.h>
13 #include <stdlib.h>
14 #include <unistd.h>
15 #include <asm/page.h>
16 #include <fcntl.h>
17
18 #include "libbb.h"
19
20
21 #define PROCPS_BUFSIZE 1024
22
23 static int read_to_buf(const char *filename, void *buf)
24 {
25         int fd;
26         ssize_t ret;
27
28         fd = open(filename, O_RDONLY);
29         if(fd < 0)
30                 return -1;
31         ret = read(fd, buf, PROCPS_BUFSIZE);
32         close(fd);
33         return ret;
34 }
35
36
37 extern procps_status_t * procps_scan(int save_user_arg0)
38 {
39         static DIR *dir;
40         struct dirent *entry;
41         static procps_status_t ret_status;
42         char *name;
43         int n;
44         char status[32];
45         char *status_tail;
46         char buf[PROCPS_BUFSIZE];
47         procps_status_t curstatus;
48         int pid;
49         long tasknice;
50         struct stat sb;
51
52         if (!dir) {
53                 dir = opendir("/proc");
54                 if(!dir)
55                         bb_error_msg_and_die("Can't open /proc");
56         }
57         for(;;) {
58                 if((entry = readdir(dir)) == NULL) {
59                         closedir(dir);
60                         dir = 0;
61                         return 0;
62                 }
63                 name = entry->d_name;
64                 if (!(*name >= '0' && *name <= '9'))
65                         continue;
66
67                 memset(&curstatus, 0, sizeof(procps_status_t));
68                 pid = atoi(name);
69                 curstatus.pid = pid;
70
71                 status_tail = status + sprintf(status, "/proc/%d", pid);
72                 if(stat(status, &sb))
73                         continue;
74                 bb_getpwuid(curstatus.user, sb.st_uid, sizeof(curstatus.user));
75
76                 strcpy(status_tail, "/stat");
77                 n = read_to_buf(status, buf);
78                 if(n < 0)
79                         continue;
80                 name = strrchr(buf, ')'); /* split into "PID (cmd" and "<rest>" */
81                 if(name == 0 || name[1] != ' ')
82                         continue;
83                 *name = 0;
84                 sscanf(buf, "%*s (%15c", curstatus.short_cmd);
85                 n = sscanf(name+2,
86                 "%c %d "
87                 "%*s %*s %*s %*s "     /* pgrp, session, tty, tpgid */
88                 "%*s %*s %*s %*s %*s " /* flags, min_flt, cmin_flt, maj_flt, cmaj_flt */
89 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
90                 "%lu %lu "
91 #else
92                 "%*s %*s "
93 #endif
94                 "%*s %*s %*s "         /* cutime, cstime, priority */
95                 "%ld "
96                 "%*s %*s %*s "         /* timeout, it_real_value, start_time */
97                 "%*s "                 /* vsize */
98                 "%ld",
99                 curstatus.state, &curstatus.ppid,
100 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
101                 &curstatus.utime, &curstatus.stime,
102 #endif
103                 &tasknice,
104                 &curstatus.rss);
105 #ifdef CONFIG_FEATURE_TOP_CPU_USAGE_PERCENTAGE
106                 if(n != 6)
107 #else
108                 if(n != 4)
109 #endif
110                         continue;
111
112                 if (curstatus.rss == 0 && curstatus.state[0] != 'Z')
113                         curstatus.state[1] = 'W';
114                 else
115                         curstatus.state[1] = ' ';
116                 if (tasknice < 0)
117                         curstatus.state[2] = '<';
118                 else if (tasknice > 0)
119                         curstatus.state[2] = 'N';
120                 else
121                         curstatus.state[2] = ' ';
122
123 #ifdef PAGE_SHIFT
124                 curstatus.rss <<= (PAGE_SHIFT - 10);     /* 2**10 = 1kb */
125 #else
126                 curstatus.rss *= (getpagesize() >> 10);     /* 2**10 = 1kb */
127 #endif
128
129                 if(save_user_arg0) {
130                         strcpy(status_tail, "/cmdline");
131                         n = read_to_buf(status, buf);
132                         if(n > 0) {
133                                 if(buf[n-1]=='\n')
134                                         buf[--n] = 0;
135                                 name = buf;
136                                 while(n) {
137                                         if(((unsigned char)*name) < ' ')
138                                                 *name = ' ';
139                                         name++;
140                                         n--;
141                                 }
142                                 *name = 0;
143                                 if(buf[0])
144                                         curstatus.cmd = strdup(buf);
145                                 /* if NULL it work true also */
146                         }
147                 }
148                 return memcpy(&ret_status, &curstatus, sizeof(procps_status_t));
149         }
150 }
151
152 /* END CODE */
153 /*
154 Local Variables:
155 c-file-style: "linux"
156 c-basic-offset: 4
157 tab-width: 4
158 End:
159 */