From: Sebastien GODARD <sysstat@users.noreply.github.com>
Date: Fri, 23 May 2014 12:37:29 +0000 (+0200)
Subject: pidstat: Add an option to filter processes by name
X-Git-Tag: v11.0.0~15
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=1bf83b1c76f48f987f1ee7526e936096abdaca82;p=sysstat

pidstat: Add an option to filter processes by name

Add "-G <process_name>" option to display only processes whose
name matches <process_name> regular expression.
While -C option filters both process and thread names, -G option
filters only process names, and displays all threads of matching
processes.

Signed-off-by: Cedric Marie <cedric.marie@openmailbox.org>
Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>
---

diff --git a/pidstat.c b/pidstat.c
index 72f558e..88c2fea 100644
--- a/pidstat.c
+++ b/pidstat.c
@@ -57,6 +57,8 @@ struct pid_stats st_pid_null;
 struct tm ps_tstamp[3];
 char commstr[MAX_COMM_LEN];
 char userstr[MAX_USER_LEN];
+char procstr[MAX_COMM_LEN];
+int show_threads = FALSE;
 
 unsigned int pid_nr = 0;	/* Nb of PID to display */
 unsigned int pid_array_nr = 0;
@@ -86,8 +88,8 @@ void usage(char *progname)
 
 	fprintf(stderr, _("Options are:\n"
 			  "[ -d ] [ -h ] [ -I ] [ -l ] [ -r ] [ -s ] [ -t ] [ -U [ <username> ] ] [ -u ]\n"
-			  "[ -V ] [ -v ] [ -w ] [ -C <command> ] [ -p { <pid> [,...] | SELF | ALL } ]\n"
-			  "[ -T { TASK | CHILD | ALL } ]\n"));
+			  "[ -V ] [ -v ] [ -w ] [ -C <command> ] [ -G <process_name> ]\n"
+			  "[ -p { <pid> [,...] | SELF | ALL } ] [ -T { TASK | CHILD | ALL } ]\n"));
 	exit(1);
 }
 
@@ -968,7 +970,10 @@ void read_stats(int curr)
  * Get current PID to display.
  * First, check that PID exists. *Then* check that it's an active process
  * and/or that the string (entered on the command line with option -C)
- * is found in command name.
+ * is found in command name, or that the process string (entered on the
+ * command line with option -G) is found either in its command name (in case
+ * PID is a process) or in command name of its thread leader (in case
+ * PID is a thread).
  *
  * IN:
  * @prev	Index in array where stats used as reference are.
@@ -1149,6 +1154,37 @@ int get_pid_to_display(int prev, int curr, int p, unsigned int activity,
 			return -1;
 	}
 
+	if (PROCESS_STRING(pidflag)) {
+		if (!(*pstc)->tgid) {
+			/* This PID is a process ("thread group leader") */
+			if (regcomp(&regex, procstr, REG_EXTENDED | REG_NOSUB) != 0) {
+				/* Error in preparing regex structure */
+				show_threads = FALSE;
+				return -1;
+			}
+
+			rc = regexec(&regex, (*pstc)->comm, 0, NULL, 0);
+			regfree(&regex);
+
+			if (rc) {
+				/* regex pattern not found in command name */
+				show_threads = FALSE;
+				return -1;
+			}
+
+			/*
+			 * This process and all its threads will be displayed.
+			 * No need to save PID value: For every process read by pidstat,
+			 * pidstat then immediately reads all its threads.
+			 */
+			show_threads = TRUE;
+		}
+		else if (!show_threads) {
+			/* This pid is a thread and is not part of a process to display */
+			return -1;
+		}
+	}
+
 	if (USER_STRING(pidflag)) {
 		if ((pwdent = getpwuid((*pstc)->uid)) != NULL) {
 			if (strcmp(pwdent->pw_name, userstr))
@@ -2053,6 +2089,11 @@ int write_stats_core(int prev, int curr, int dis, int disp_avg,
 		itv = g_itv;
 	}
 
+	if (PROCESS_STRING(pidflag)) {
+		/* Reset "show threads" flag */
+		show_threads = FALSE;
+	}
+
 	if (DISPLAY_ONELINE(pidflag)) {
 		if (DISPLAY_TASK_STATS(tskflag)) {
 			again += write_pid_task_all_stats(prev, curr, dis,
@@ -2371,6 +2412,20 @@ int main(int argc, char **argv)
 			}
 		}
 
+		else if (!strcmp(argv[opt], "-G")) {
+			if (argv[++opt]) {
+				strncpy(procstr, argv[opt++], MAX_COMM_LEN);
+				procstr[MAX_COMM_LEN - 1] = '\0';
+				pidflag |= P_F_PROCSTR;
+				if (!strlen(procstr)) {
+					usage(argv[0]);
+				}
+			}
+			else {
+				usage(argv[0]);
+			}
+		}
+
 		else if (!strcmp(argv[opt], "-T")) {
 			if (argv[++opt]) {
 				if (tskflag) {
diff --git a/pidstat.h b/pidstat.h
index 14531c1..6ca9473 100644
--- a/pidstat.h
+++ b/pidstat.h
@@ -52,6 +52,7 @@
 #define P_D_CMDLINE	0x080
 #define P_D_USERNAME	0x100
 #define P_F_USERSTR	0x200
+#define P_F_PROCSTR	0x400
 
 #define DISPLAY_PID(m)		(((m) & P_D_PID) == P_D_PID)
 #define DISPLAY_ALL_PID(m)	(((m) & P_D_ALL_PID) == P_D_ALL_PID)
@@ -63,6 +64,7 @@
 #define DISPLAY_CMDLINE(m)	(((m) & P_D_CMDLINE) == P_D_CMDLINE)
 #define DISPLAY_USERNAME(m)	(((m) & P_D_USERNAME) == P_D_USERNAME)
 #define USER_STRING(m)		(((m) & P_F_USERSTR) == P_F_USERSTR)
+#define PROCESS_STRING(m)	(((m) & P_F_PROCSTR) == P_F_PROCSTR)
 
 /* Per-process flags */
 #define F_NO_PID_IO	0x01