From dab3cff7a17364cd87201e3f58080d523eaf44a6 Mon Sep 17 00:00:00 2001
From: Sebastien GODARD <sysstat@users.noreply.github.com>
Date: Sat, 4 Apr 2020 10:45:48 +0200
Subject: [PATCH] Fix #228: pidstat's -l replaces "\0" with " ", displaying
 unnecesary data

Fix issue #228.
Also add use cases to simulation test environment.

Signed-off-by: Sebastien GODARD <sysstat@users.noreply.github.com>
---
 pidstat.c                                |   9 ++++++---
 tests/root1/proc/8407/cmdline            | Bin 35 -> 99 bytes
 tests/root1/proc/8407/task/8407/cmdline  | Bin 35 -> 99 bytes
 tests/root2/proc/7900/task/10334/cmdline | Bin 27 -> 14 bytes
 tests/root2/proc/8407/cmdline            | Bin 35 -> 99 bytes
 tests/root2/proc/8407/task/8407/cmdline  | Bin 35 -> 99 bytes
 tests/root3/proc/7900/task/10334/cmdline | Bin 27 -> 14 bytes
 7 files changed, 6 insertions(+), 3 deletions(-)

diff --git a/pidstat.c b/pidstat.c
index 46b8771..0b4362e 100644
--- a/pidstat.c
+++ b/pidstat.c
@@ -650,7 +650,7 @@ int read_proc_pid_cmdline(pid_t pid, struct st_pid *plist, pid_t tgid)
 	FILE *fp;
 	char filename[128], line[MAX_CMDLINE_LEN];
 	size_t len;
-	int i;
+	int i, found = FALSE;
 
 	if (tgid) {
 		sprintf(filename, TASK_CMDLINE, tgid, pid);
@@ -669,8 +669,11 @@ int read_proc_pid_cmdline(pid_t pid, struct st_pid *plist, pid_t tgid)
 	fclose(fp);
 
 	if (len) {
-		for (i = 0; i < len - 1; i++) {
-			if (line[i] == '\0') {
+		for (i = len - 2; i >= 0; i--) {
+			if (line[i]) {
+				found = TRUE;
+			}
+			else if (found) {
 				line[i] = ' ';
 			}
 		}
diff --git a/tests/root1/proc/8407/cmdline b/tests/root1/proc/8407/cmdline
index 8d4f0e64e8b76ad18e3d37bcc9f2773ae0477391..349685443ad97ccf07765f9579579087034e85d4 100644
GIT binary patch
literal 99
tcmdNdEiTf}$xKSENKMvH&&$tE)h$Ua%FWD6%+W1QEh<YbVxSOk0RT8u4KV-!

delta 4
LcmYdRo}df>13Upb

diff --git a/tests/root1/proc/8407/task/8407/cmdline b/tests/root1/proc/8407/task/8407/cmdline
index 8d4f0e64e8b76ad18e3d37bcc9f2773ae0477391..349685443ad97ccf07765f9579579087034e85d4 100644
GIT binary patch
literal 99
tcmdNdEiTf}$xKSENKMvH&&$tE)h$Ua%FWD6%+W1QEh<YbVxSOk0RT8u4KV-!

delta 4
LcmYdRo}df>13Upb

diff --git a/tests/root2/proc/7900/task/10334/cmdline b/tests/root2/proc/7900/task/10334/cmdline
index f6669f2a99b1b2056fcbe8cc684bf27e254bb96a..334128be67ace9881b3ba105fa1791c64845a1b8 100644
GIT binary patch
literal 14
VcmYdE&d*C@D9<m-PAy{K0stoO1g`)9

literal 27
bcmdNdEiTf}$xJdc(ND`PN=?hJfYA&9g}n)$

diff --git a/tests/root2/proc/8407/cmdline b/tests/root2/proc/8407/cmdline
index 8d4f0e64e8b76ad18e3d37bcc9f2773ae0477391..349685443ad97ccf07765f9579579087034e85d4 100644
GIT binary patch
literal 99
tcmdNdEiTf}$xKSENKMvH&&$tE)h$Ua%FWD6%+W1QEh<YbVxSOk0RT8u4KV-!

delta 4
LcmYdRo}df>13Upb

diff --git a/tests/root2/proc/8407/task/8407/cmdline b/tests/root2/proc/8407/task/8407/cmdline
index 8d4f0e64e8b76ad18e3d37bcc9f2773ae0477391..349685443ad97ccf07765f9579579087034e85d4 100644
GIT binary patch
literal 99
tcmdNdEiTf}$xKSENKMvH&&$tE)h$Ua%FWD6%+W1QEh<YbVxSOk0RT8u4KV-!

delta 4
LcmYdRo}df>13Upb

diff --git a/tests/root3/proc/7900/task/10334/cmdline b/tests/root3/proc/7900/task/10334/cmdline
index f6669f2a99b1b2056fcbe8cc684bf27e254bb96a..334128be67ace9881b3ba105fa1791c64845a1b8 100644
GIT binary patch
literal 14
VcmYdE&d*C@D9<m-PAy{K0stoO1g`)9

literal 27
bcmdNdEiTf}$xJdc(ND`PN=?hJfYA&9g}n)$

-- 
2.40.0