/*
 * listprusage - list various prusage statistics by process. Solaris, C.
 *
 * 01-Jul-2005, ver 0.70	(first release. check for newer versions)
 *
 * USAGE:	listprusage
 *
 * COMPILE:	cc -o listprusage listprusage.c
 *
 * FIELDS:
 *		PID		process ID
 *		MINF		minor faults
 *		MAJF		major faults
 * 		INBLK		in blocks
 *		OUBLK		out blocks
 *		SYSC		system calls
 *		IOCH		read/write characters
 *
 * NOTES: 
 * - MINF always reports zero (Solaris doesn't increment it).
 * - This is the first release, future versions will have options.
 *
 * Standard Disclaimer: This is freeware, use at your own risk.
 *
 * COPYRIGHT: Copyright (c) 2005 Brendan Gregg.
 *
 * 01-Jul-2005	Brendan Gregg	Created this.
 */

#include <stdio.h>
#include <stdlib.h>
#include <procfs.h>
#include <dirent.h>
#include <string.h>

static void printprusage(pid_t pid);

int
main()
{
	DIR *dirp;
	struct dirent *dp;
	pid_t pid;

	/* open /proc for list of processes */
	if ((dirp = opendir("/proc")) == NULL) {
		perror("ERROR1: Couldn't open /proc");
		return (1);
	}

	/* print header */
	(void) printf("%6s %6s %6s %6s %6s %10s %12s\n",
	    "PID", "MINF", "MAJF", "INBLK", "OUBLK", "SYSC", "IOCH");

	/* main loop */
	for (;;) {
		/* read filename */
		if ((dp = readdir(dirp)) == NULL) break;
		if (strcmp(dp->d_name, ".") == 0) continue;
		if (strcmp(dp->d_name, "..") == 0) continue;

		/* print process details */
		pid = atoi(dp->d_name);
		(void) printprusage(pid);
	}

	(void) closedir(dirp);

	return (0);
}

/*
 * printprusage
 *
 * this function takes a PID and prints out various prusage statistics.
 */
static void
printprusage(pid_t pid)
{
	struct prusage pru;
	struct prusage *prup = &pru;
	char path[64];
	FILE *filep;

	/* read prusage data */
	(void) sprintf(path, "/proc/%d/usage", (int)pid);
	if (!(filep = fopen(path, "r")))
		return;
	if (!(fread(prup, sizeof (struct prusage), 1, filep)))
		return;
	(void) fclose(filep);

	/* print output line */
	(void) printf("%6d %6lu %6lu %6lu %6lu %10lu %12lu\n",
	    pid, prup->pr_minf, prup->pr_majf, prup->pr_inblk, prup->pr_oublk,
	    prup->pr_sysc, prup->pr_ioch);
}