Optimised pst3 for systems with large number of processes (Duncan Ferguson)

git-svn-id: https://nagiosplug.svn.sourceforge.net/svnroot/nagiosplug/nagiosplug/trunk@2010 f882894a-f735-0410-b71e-b25c423dba1c

NEWS

@@ -2,6 +2,7 @@ This file documents the major additions and syntax changes between releases.
 
 1.4.?? ??th ??? 200?
 	Fix Debian bug #460097: check_http --max-age broken (Hilko Bengen)
+	Optimised pst3 for systems with large number of processes (Duncan Ferguson)
 	Updated Nagios::Plugin to 0.27
 
 1.4.12 27th May 2008

plugins-root/pst3.c

@@ -1,16 +1,36 @@
-/*	pst3.c
+/*****************************************************************************
+* 
+* pst3
+* 
+* License: GPL
+* Copyright (c) 2008 Nagios Plugin 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 the kernel memory structures, so needs
+* to be executed as root
 *
-*  Third version to get process arg info; this time by using
-*  a combination of reading the /proc/<pid>/psinfo structures
-*  and reading the complete arg vector from kernel memory structures.
-*
-*  Developed and tested under Solaris 5.8 (both 32 and 64 bit modes).
-*
-*  NOTE:  This program must be setuid-root (or run by root) to work!
-*
-*	Written: 2005-04-28	R.W.Ingraham
-*/
-
+* Originally written by R.W.Ingraham
+* 
+* 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/>.
+* 
+*****************************************************************************/
 
 #define _KMEMUSER	1
 
@@ -37,6 +57,8 @@
 
 #define PROC_DIR	"/proc"
 #define MAX_PATH	1024
+#define OK 0
+#define FAIL NULL
 
 
 /*
@@ -59,12 +81,9 @@ static char **       myArgv;
  *	Prototypes
  */
 
-static int HandleFile (struct dirent *pDent);
-static int HandlePsInfo (char *szPath, psinfo_t *pPsInfo);
-static int GetArgVectors (pid_t pid);
-static void ShowArgVectors (void);
-static void ReleaseArgVectors();
-
+static int output_info(struct proc *proc_kvm, psinfo_t procinfo,char **proc_argv);
+static psinfo_t get_procinfo(struct proc *proc);
+static int HandleProc(struct proc *proc);
 
 /*----------------------------------------------------------------------------*/
 
@@ -73,7 +92,8 @@ int main (int argc, char **argv)
 	DIR *pDir;
 	struct dirent *pDent;
 	int retcode = 0;
-
+	struct proc *proc;
+	struct pid pid;
 
 	/* Set our program name global */
 	if ((szProg = strrchr(argv[0], '/')) != NULL)
@@ -95,26 +115,28 @@ int main (int argc, char **argv)
 		exit(2);
 	}
 
-	/* Open the /proc directory */
-	if ((pDir = opendir(PROC_DIR)) != NULL)
-	{
-		/* Display column headings */
-		printf("S   UID   PID  PPID    VSZ    RSS %%CPU COMMAND ARGS\n");
-
-		/* Zip through all of the process entries */
-		while ((pDent = readdir(pDir)) != NULL)
-		{
-			/* Handle each pid sub-directory */
-			HandleFile(pDent);
-		}
-
-		/* Close the directory */
-		closedir(pDir);
-	}
-	else	/* ERROR: Failure to open PROC_DIR */
-	{
-		fprintf(stderr, "%s: Failed to open \"%s\": %s\n", szProg, PROC_DIR, strerror(errno));
-		retcode = 3;
+	/* reset to first proc in list */
+	if(kvm_setproc(kd) == -1) {
+                perror("kvm_setproc");
+                exit(2);
+        }
+
+	/* 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 = kvm_nextproc(kd)) != 0) {
+		HandleProc(proc);
 	}
 
 	/* Close the handle to the running kernel image */
@@ -125,129 +147,76 @@ int main (int argc, char **argv)
 
 /*----------------------------------------------------------------------------*/
 
-static int HandleFile (struct dirent *pDent)
+static int HandleProc(struct proc *proc)
 {
-	char szPath[MAX_PATH];
-	psinfo_t sPsInfo;
-	int fd, len;
-	int rc = 0;
-
-	/* Skip files beginning with a "." */
-	if (pDent->d_name[0] == '.')
-		return 0;
-
-	/* Cosntruct the path to the psinfo file */
-	len = sprintf(szPath, "%s/%s/psinfo", PROC_DIR, pDent->d_name);
-
-	/* Open the psinfo file for this pid and print out its arg vectors */
-	if ((fd = open(szPath, O_RDONLY)) >= 0)
-	{
-		/* Read the psinfo struct */
-		if ((len = read(fd, &sPsInfo, sizeof(sPsInfo))) != sizeof(sPsInfo))
-		{
-			rc = errno;
-			fprintf(stderr, "%s: Read error of psinfo structure (%d)\n", szPath, len);
-			return rc;
-		}
-
-		/* Close the psinfo file */
-		close(fd);
+	struct pid pid;
+	struct user *user;
+	psinfo_t procinfo;
+	char **proc_argv = 0;
 
-		/* Pass psinfo struct to reporting function */
-		HandlePsInfo(szPath, &sPsInfo);
-	}
-	else if (errno != ENOENT)
-	{
-		rc = errno;
-		fprintf(stderr, "%s: %s\n", szPath, strerror(errno));
+	if(kvm_kread(kd, (unsigned long) proc->p_pidp, (char *) &pid, sizeof pid) == -1) {
+		perror("kvm_read error");
+		exit(2);
 	}
+	proc->p_pidp = &pid;
+	user = kvm_getu(kd, proc);
 
-	return 0;
-}
-
-/*----------------------------------------------------------------------------*/
-
-static int HandlePsInfo (char *szPath, psinfo_t *pPsInfo)
-{
-	int retcode;
-	char *thisProg;
-
-	/* Make sure that the process is still there */
-	if ((retcode = GetArgVectors(pPsInfo->pr_pid)) == 0)
-	{
-		/* We use the program name from the kvm argv[0] instead
-		 * of pr_fname from the psinfo struct because pr_fname
-		 * may be truncated.
-		 *
-		 * Also, strip-off leading path information.
-		 */
-		if ((thisProg = strrchr(myArgv[0], '/')) != NULL)
-			thisProg++;
-		else
-			thisProg = myArgv[0];
- 
-		/* Display the ps columns (except for argv) */
-		printf("%c %5d %5d %5d %6lu %6lu %4.1f %s ",
-			pPsInfo->pr_lwp.pr_sname,
-			(int)(pPsInfo->pr_euid),
-			(int)(pPsInfo->pr_pid),
-			(int)(pPsInfo->pr_ppid),
-			(unsigned long)(pPsInfo->pr_size),
-			(unsigned long)(pPsInfo->pr_rssize),
-			((float)(pPsInfo->pr_pctcpu) / 0x8000 * 100.0),
-			thisProg);
-
-		/* Display the arg vectors associated with this pid */
-		ShowArgVectors();
-
-		/* Release the arg vector buffer memory */
-		ReleaseArgVectors();
+	if(kvm_getcmd(kd, proc, user, &proc_argv, NULL) == -1) {
+		return FAIL;
 	}
 
-	return retcode;
+	procinfo = get_procinfo(proc);
+	return output_info(proc, procinfo, proc_argv);
 }
 
-/*----------------------------------------------------------------------------*/
-
-static int GetArgVectors (pid_t pid)
+static psinfo_t get_procinfo(struct proc *proc)
 {
-	int retcode = 1;
+	char procpath[MAX_PATH];
+	psinfo_t procinfo;
+	int fd, len;
+
+	sprintf(procpath, "/proc/%d/psinfo", proc->p_pidp->pid_id);
 
-	/* Get the proc structure for the specified PID */
-	if ((pProc = kvm_getproc(kd, pid)) != NULL)
+	if ((fd = open(procpath, O_RDONLY)) >= 0)
 	{
-		/* Save a copy of the process' u-area */
-		if ((pUser = kvm_getu(kd, pProc)) != NULL)
+		if ((len = read(fd, &procinfo, sizeof(procinfo))) != sizeof(procinfo))
 		{
-			/* Reconstruct the process' argv vector array */
-			if (kvm_getcmd(kd, pProc, pUser, &myArgv, NULL) == 0)
-			{
-				retcode = 0;
-			}
+			fprintf(stderr,"%s: Read error of psingo structure (%d)\n", procpath, len);
+			exit(2);
 		}
+		close(fd);
 	}
+	return procinfo;
 
-	return retcode;
 }
 
-/*----------------------------------------------------------------------------*/
-
-static void ShowArgVectors (void)
+static int output_info(struct proc *proc_kvm, psinfo_t procinfo, char **proc_argv)
 {
+	char *procname;
 	int i;
 
-	for (i=0; myArgv[i]; i++)
-	{
-		printf(" %s", myArgv[i]);
+	if((procname = strrchr(proc_argv[0], '/')) != NULL)
+		procname++;
+	else
+		procname = proc_argv[0];
+
+	printf("%c %5d %5d %5d %6lu %6lu %4.1f %s ",
+		procinfo.pr_lwp.pr_sname,
+		(int)(procinfo.pr_euid),
+		(int)proc_kvm->p_pidp->pid_id,
+		(int)proc_kvm->p_ppid,
+		(unsigned long)(procinfo.pr_size),
+		(unsigned long)(procinfo.pr_rssize),
+		((float)(procinfo.pr_pctcpu) / 0x8000 * 100.0),
+		procname
+	);
+
+	for(i=0;proc_argv[i];i++) {
+		printf(" %s", proc_argv[i]);
 	}
-	printf("\n");
-}
 
-/*----------------------------------------------------------------------------*/
+	printf("\n");
 
-static void ReleaseArgVectors()
-{
-	/* NOOP */
+	return OK;
 }
 
-/*----------------------------------------------------------------------------*/