/*****************************************************************************
 *
 * pst3
 *
 * License: GPL
 * Copyright (c) 2008 Monitoring Plugins Development Team
 *
 * Description:
 *
 * This file contains the pst3 executable. This is a replacement ps command
 * for Solaris to get output which provides a long argument listing, which
 * is not possible with the standard ps command (due to truncation). /usr/ucb/ps
 * also has issues where some fields run into each other.
 *
 * This executable works by reading process address structures, so needs
 * to be executed as root
 *
 * Originally written by R.W.Ingraham
 * Rewritten by Duncan Ferguson (Altinity Ltd, June 2008)
 *   The rewrite was necessary as /dev/kmem is not available within
 *   non-global zones on Solaris 10
 *
 *   Details for rewrite came from
 *    source of /usr/ucb/ps on Solaris:
 *     http://cvs.opensolaris.org/source/xref/onnv/onnv-gate/usr/src/ucbcmd/ps/ps.c#argvoff
 *    usenet group posting
 *     http://groups.google.com/group/comp.unix.solaris/tree/browse_frm/month/2001-09/bfa40c08bac819a2?rnum=141&_done=%2Fgroup%2Fcomp.unix.solaris%2Fbrowse_frm%2Fmonth%2F2001-09%3F
 *
 * 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 3 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, see <http://www.gnu.org/licenses/>.
 *
 *****************************************************************************/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <dirent.h>
#include <errno.h>
#include <fcntl.h>
#include <procfs.h>
#include <sys/types32.h>

/*
 *  Constants
 */

#define PROC_DIR "/proc"
#define ARGS     30

/*
 *  Globals
 */

static char *szProg;

/*
 *  Prototypes
 */
void usage();

/*----------------------------------------------------------------------------*/

int main(int argc, char **argv) {
	DIR *procdir;
	struct dirent *proc;
	char ps_name[ARGS];
	char as_name[ARGS];
	psinfo_t psinfo;

	/* Set our program name global */
	if ((szProg = strrchr(argv[0], '/')) != NULL) {
		szProg++;
	} else {
		szProg = argv[0];
	}

	/* if given any parameters, print out help */
	if (argc > 1) {
		(void)usage();
		exit(1);
	}

	/* Make sure that our euid is root */
	if (geteuid() != 0) {
		fprintf(stderr, "%s: This program can only be run by the root user!\n", szProg);
		exit(1);
	}

	if ((procdir = opendir(PROC_DIR)) == NULL) {
		fprintf(stderr, "%s: cannot open PROC directory %s\n", szProg, PROC_DIR);
		exit(1);
	}

	/* Display column headings */
	printf("%c %5s %5s %5s %6s %6s %4s %s %s\n", 'S', "UID", "PID", "PPID", "VSZ", "RSS", "%CPU",
		   "COMMAND", "ARGS");

	/* Zip through all of the process entries */
	while ((proc = readdir(procdir))) {
		int ps_fd;
		int as_fd;
		off_t argoff;
		int i;
		char *args;
		char *procname;
		char *ptr;
		int argslen;
		uintptr_t args_addr;
		;
		uintptr_t *args_vecs;
		;
		int args_count;

		if (proc->d_name[0] == '.') {
			continue;
		}

		sprintf(ps_name, "%s/%s/%s", PROC_DIR, proc->d_name, "psinfo");
		sprintf(as_name, "%s/%s/%s", PROC_DIR, proc->d_name, "as");
	try_again:
		if ((ps_fd = open(ps_name, O_RDONLY)) == -1) {
			continue;
		}

		if ((as_fd = open(as_name, O_RDONLY)) == -1) {
			close(ps_fd);
			continue;
		}

		if (read(ps_fd, &psinfo, sizeof(psinfo)) != sizeof(psinfo)) {
			int err = errno;
			close(ps_fd);
			close(as_fd);
			if (err == EAGAIN) {
				goto try_again;
			}
			if (err != ENOENT) {
				fprintf(stderr, "%s: read() on %s: %s\n", szProg, ps_name, strerror(err));
			}
			continue;
		}
		close(ps_fd);

		/* system process, ignore since the previous version did */
		if (psinfo.pr_nlwp == 0 || strcmp(psinfo.pr_lwp.pr_clname, "SYS") == 0) {
			continue;
		}

		/* get the procname to match previous versions */
		procname = strdup(psinfo.pr_psargs);
		if ((ptr = strchr(procname, ' ')) != NULL) {
			*ptr = '\0';
		}
		if ((ptr = strrchr(procname, '/')) != NULL) {
			ptr++;
		} else {
			ptr = procname;
		}

		/*
		 * print out what we currently know
		 */
		printf("%c %5d %5d %5d %6lu %6lu %4.1f %s ", psinfo.pr_lwp.pr_sname, psinfo.pr_euid,
			   psinfo.pr_pid, psinfo.pr_ppid, psinfo.pr_size, psinfo.pr_rssize,
			   ((float)(psinfo.pr_pctcpu) / 0x8000 * 100.0), ptr);
		free(procname);

		/*
		 * and now for the command line stuff
		 */

		args_addr = psinfo.pr_argv;
		args_count = psinfo.pr_argc;
		args_vecs = malloc(args_count * sizeof(uintptr_t));

		if (psinfo.pr_dmodel == PR_MODEL_NATIVE) {
			/* this process matches target process */
			pread(as_fd, args_vecs, args_count * sizeof(uintptr_t), args_addr);
		} else {
			/* this process is 64bit, target process is 32 bit*/
			caddr32_t *args_vecs32 = (caddr32_t *)args_vecs;
			pread(as_fd, args_vecs32, args_count * sizeof(caddr32_t), args_addr);
			for (i = args_count - 1; i >= 0; --i) {
				args_vecs[i] = args_vecs32[i];
			}
		}

		/*
		 * now read in the args - if what we read in fills buffer
		 * resize buffer and reread that bit again
		 */
		argslen = ARGS;
		args = malloc(argslen + 1);
		for (i = 0; i < args_count; i++) {
			memset(args, '\0', argslen + 1);
			if (pread(as_fd, args, argslen, args_vecs[i]) <= 0) {
				break;
			}
			args[argslen] = '\0';
			if (strlen(args) == argslen) {
				argslen += ARGS;
				args = realloc(args, argslen + 1);
				i--;
				continue;
			}
			printf(" %s", args);
		}
		free(args_vecs);
		free(args);
		close(as_fd);
		printf("\n");
	}

	(void)closedir(procdir);

	return (0);
}

/*----------------------------------------------------------------------------*/

void usage() {
	printf("%s: Help output\n\n", szProg);
	printf("If this program is given any arguments, this help is displayed.\n");
	printf("This command is used to print out the full command line for all\n");
	printf("running processes because /usr/bin/ps is limited to 80 chars and\n");
	printf("/usr/ucb/ps can merge columns together.\n\n");
	printf("Columns are:\n");
	printf("\tS        - State of process - see 'ps' man page\n");
	printf("\tUID      - UID of the process owner\n");
	printf("\tPID      - PID of the process\n");
	printf("\tPPID     - PID of the parent process\n");
	printf("\tVSZ      - Virtual memory usage (kilobytes)\n");
	printf("\tRSS      - Real memory usage (kilobytes)\n");
	printf("\t%%CPU     - CPU usage\n");
	printf("\tCOMMAND  - Command being run\n");
	printf("\tARGS     - Full command line with arguments\n");
	return;
}
