/**
*
* cpulimit - a CPU limiter for Linux
*
* Copyright (C) 2005-2012, by: Angelo Marletta <angelo dot marletta at gmail dot com>
*
* 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
#include <sys/vfs.h>
static int get_boot_time()
{
int uptime = 0;
FILE *fp = fopen ("/proc/uptime", "r");
if (fp != NULL)
{
char buf[BUFSIZ];
char *b = fgets(buf, BUFSIZ, fp);
if (b == buf)
{
char *end_ptr;
double upsecs = strtod(buf, &end_ptr);
uptime = (int)upsecs;
}
fclose (fp);
}
time_t now = time(NULL);
return now - uptime;
}
static int check_proc()
{
struct statfs mnt;
if (statfs("/proc", &mnt) < 0)
return 0;
if (mnt.f_type!=0x9fa0)
return 0;
return 1;
}
int init_process_iterator(struct process_iterator *it, struct process_filter *filter)
{
if (!check_proc()) {
fprintf(stderr, "procfs is not mounted!\nAborting\n");
exit(-2);
}
//open a directory stream to /proc directory
if ((it->dip = opendir("/proc")) == NULL)
{
perror("opendir");
return -1;
}
it->filter = filter;
it->boot_time = get_boot_time();
return 0;
}
static int read_process_info(pid_t pid, struct process *p)
{
static char buffer[1024];
static char statfile[32];
static char exefile[1024];
p->pid = pid;
//read stat file
sprintf(statfile, "/proc/%d/stat", p->pid);
FILE *fd = fopen(statfile, "r");
if (fd==NULL) return -1;
if (fgets(buffer, sizeof(buffer), fd)==NULL) {
fclose(fd);
return -1;
}
fclose(fd);
char *token = strtok(buffer, " ");
int i;
for (i=0; i<3; i++) token = strtok(NULL, " ");
p->ppid = atoi(token);
for (i=0; i<10; i++)
token = strtok(NULL, " ");
p->cputime = atoi(token) * 1000 / HZ;
token = strtok(NULL, " ");
p->cputime += atoi(token) * 1000 / HZ;
for (i=0; i<7; i++)
token = strtok(NULL, " ");
p->starttime = atoi(token) / sysconf(_SC_CLK_TCK);
//read command line
sprintf(exefile,"/proc/%d/cmdline", p->pid);
fd = fopen(exefile, "r");
if (fgets(buffer, sizeof(buffer), fd)==NULL) {
fclose(fd);
return -1;
}
fclose(fd);
strcpy(p->command, buffer);
return 0;
}
static pid_t getppid_of(pid_t pid)
{
char statfile[20];
char buffer[1024];
sprintf(statfile, "/proc/%d/stat", pid);
FILE *fd = fopen(statfile, "r");
if (fd==NULL) return -1;
if (fgets(buffer, sizeof(buffer), fd)==NULL) {
fclose(fd);
return -1;
}
fclose(fd);
char *token = strtok(buffer, " ");
int i;
for (i=0; i<3; i++) token = strtok(NULL, " ");
return atoi(token);
}
static int is_child_of(pid_t child_pid, pid_t parent_pid)
{
int ppid = child_pid;
while(ppid > 1 && ppid != parent_pid) {
ppid = getppid_of(ppid);
}
return ppid == parent_pid;
}
int get_next_process(struct process_iterator *it, struct process *p)
{
if (it->dip == NULL)
{
//end of processes
return -1;
}
if (it->filter->pid != 0 && !it->filter->include_children)
{
int ret = read_process_info(it->filter->pid, p);
//p->starttime += it->boot_time;
closedir(it->dip);
it->dip = NULL;
if (ret != 0) return -1;
return 0;
}
struct dirent *dit = NULL;
//read in from /proc and seek for process dirs
while ((dit = readdir(it->dip)) != NULL) {
if(strtok(dit->d_name, "0123456789") != NULL)
continue;
p->pid = atoi(dit->d_name);
if (it->filter->pid != 0 && it->filter->pid != p->pid && !is_child_of(p->pid, it->filter->pid)) continue;
read_process_info(p->pid, p);
//p->starttime += it->boot_time;
break;
}
if (dit == NULL)
{
//end of processes
closedir(it->dip);
it->dip = NULL;
return -1;
}
return 0;
}
int close_process_iterator(struct process_iterator *it) {
if (it->dip != NULL && closedir(it->dip) == -1) {
perror("closedir");
return 1;
}
it->dip = NULL;
return 0;
}