#! /bin/sh /usr/share/dpatch/dpatch-run
## 20_pidof.dpatch by Petter Reinholdtsen
##
## All lines beginning with `## DP:' are a description of the patch.
## DP: Modify pidof to not print empty line if no pid was found. (bug: #225476)

@DPATCH@
--- sysvinit-2.86.ds1.orig/src/killall5.c
+++ sysvinit-2.86.ds1/src/killall5.c
@@ -378,8 +391,8 @@
 	int		foundone = 0;
 	int		ok = 0;
 
-	/* Try to stat the executable. */
-	if (prog[0] == '/' && stat(prog, &st) == 0) dostat++;
+	if (! prog)
+		return NULL;
 
 	/* Get basename of program. */
 	if ((s = strrchr(prog, '/')) == NULL)
@@ -387,9 +400,16 @@
 	else
 		s++;
 
+	if (! *s)
+		return NULL;
+
 	q = (PIDQ_HEAD *)xmalloc(sizeof(PIDQ_HEAD));
 	q = init_pid_q(q);
 
+	/* Try to stat the executable. */
+	if (prog[0] == '/' && stat(prog, &st) == 0)
+		dostat++;
+
 	/* First try to find a match based on dev/ino pair. */
 	if (dostat) {
 		for (p = plist; p; p = p->next) {
@@ -404,15 +424,35 @@
 	if (!foundone) for (p = plist; p; p = p->next) {
 		ok = 0;
 
-		/* Compare name (both basename and full path) */
-		ok += (p->argv0 && strcmp(p->argv0, prog) == 0);
-		ok += (p->argv0 && strcmp(p->argv0base, s) == 0);
+		/*             matching        nonmatching
+		 * proc name   prog name       prog name
+		 * ---         -----------     ------------
+		 *   b         b, p/b, q/b
+		 * p/b         b, p/b          q/b
+		 *
+		 * Algorithm: Match if:
+		 *    cmd = arg
+		 * or cmd = base(arg)
+		 * or base(cmd) = arg
+		 *
+		 * Specifically, do not match just because base(cmd) = base(arg)
+		 * as was done in earlier versions of this program, since this
+		 * allows /aaa/foo to match /bbb/foo .
+		 */
+		ok |=
+			(p->argv0 && strcmp(p->argv0, prog) == 0)
+			|| (p->argv0 && s != prog && strcmp(p->argv0, s) == 0)
+			|| (p->argv0base && strcmp(p->argv0base, prog) == 0);
 
 		/* For scripts, compare argv[1] as well. */
-		if (scripts_too && p->argv1 &&
-		    !strncmp(p->statname, p->argv1base, STATNAMELEN)) {
-			ok += (strcmp(p->argv1, prog) == 0);
-			ok += (strcmp(p->argv1base, s) == 0);
+		if (
+			scripts_too && p->statname && p->argv1base
+			&& !strncmp(p->statname, p->argv1base, STATNAMELEN)
+		) {
+			ok |=
+				(p->argv1 && strcmp(p->argv1, prog) == 0)
+				|| (p->argv1 && s != prog && strcmp(p->argv1, s) == 0)
+				|| (p->argv1base && strcmp(p->argv1base, prog) == 0);
 		}
 
 		/*
@@ -423,7 +463,7 @@
 		    (p->argv0 == NULL ||
 		     p->argv0[0] == 0 ||
 		     strchr(p->argv0, ' '))) {
-			ok += (strcmp(p->statname, s) == 0);
+			ok |= (strcmp(p->statname, s) == 0);
 		}
 		if (ok) add_pid_to_q(q, p);
 	}
@@ -548,7 +588,8 @@
 			}
 		}
 	}
-	printf("\n");
+	if (!first)
+		printf("\n");
 	closelog();
 	return(first ? 1 : 0);
 }