dpmd.c

Linux下动态电源管理(Dynamic Power Management)的用户守护进程

#include <ctype.h>
#include <dirent.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "dpmd.h"

static struct dpmd_config dpmd_conf;

#define DEFAULT_CONFIG_FILE  "/usr/local/etc/dpmd.conf"

struct dpmd_programs {
	char name[32];
	struct dpmd_programs *next;
};

static struct dpmd_programs *programs;
static unsigned int idle_time = 0;

static int insert_dpmd_programs(char *progname)
{
	struct dpmd_programs *prev, *prog;

	prev = prog = programs;

	while (prog) {
		prev = prog;
		prog = prog->next;
	}

	prog = (struct dpmd_programs *)malloc(sizeof(*prog));
	if (!prog) {
		return -1;
	}
	memset(prog, 0, sizeof(*prog));

	memcpy(prog->name, progname, 31);

	if (prev)
		prev->next = prog;
	else
		programs = prog;

	return 0;
}

static int free_dpmd_programs(void)
{
	struct dpmd_programs *prog = programs;

	while (prog) {
		free(prog);
		prog = prog->next;
	}

	programs = 0L;

	return 0;
}

/*
 * Main routine
 */

int main(int argc, char *argv[])
{
	int ch, ret;
	void *tmp;
	char *t_prog;
	char *config_file, *policy;
	struct dpmd_programs *prog;

	config_file = DEFAULT_CONFIG_FILE;

	while ((ch = getopt(argc, argv, "f:h")) != -1) {
		switch (ch) {
		case 'h':
			printf("dpmd [-f config_file] [-h]\n");
			exit(-1);
			break;
		case 'f':
			config_file = optarg;
			break;
		default:
			break;
		}
	}

	parse_config(config_file, &dpmd_conf);

	t_prog = strtok(dpmd_conf.programs,",");
	do {
		if (t_prog == NULL)
			continue;

		insert_dpmd_programs(t_prog);
	} while ((t_prog = strtok(NULL,",")) != NULL);

	// Loop
	while (1) {
		ret = get_running_programs();

		/* check for programs */
		prog = programs;
		while (prog) {
			if ((ret = find_program(prog->name))) {
				policy = dpmd_conf.policy_high;
				idle_time = 0;
				break;
			}
			prog = prog->next;
		}

		/* check for cpu usage */
		get_cpu();
		cpu_parse(dpmd_conf.cpu_interval, &tmp);
		ret = cpu_evaluate(tmp);
		if (ret) {
			policy = dpmd_conf.policy_low;
			idle_time += dpmd_conf.poll_interval;
		}
		else {
			policy = dpmd_conf.policy_high;
			idle_time = 0;
		}

		/* apply the policy */
		dpmd_set_policy(policy);

		if (idle_time >= (dpmd_conf.suspend_interval + dpmd_conf.poll_interval)) {
			idle_time = 0;
//			dpmd_suspend(); /* suspend the system */
		}

		/* wait for poll_interval seconds */
		sleep(dpmd_conf.poll_interval);
	}

	free_dpmd_programs();

	return 0;
}