pidof/killall: allow find_pid_by_name to find running

 processes started as scripts_with_name_longer_than_15_bytes.sh
 closes bug 4054 (and is generally neat)

2 files changed, 42 insertions, 18 deletions

diff --git a/libbb/find_pid_by_name.c b/libbb/find_pid_by_name.c
index ae2f116..2ee423c 100644
--- a/libbb/find_pid_by_name.c
+++ b/libbb/find_pid_by_name.c
@@ -38,6 +38,35 @@ execXXX("/proc/self/exe", applet_name, params....)
 and therefore comm field contains "exe".
 */
 
+static int comm_match(procps_status_t *p, const char *procName)
+{
+	int argv1idx;
+
+	/* comm does not match */
+	if (strncmp(p->comm, procName, 15) != 0)
+		return 0;
+
+	/* in Linux, if comm is 15 chars, it may be a truncated */
+	if (p->comm[14] == '\0') /* comm is not truncated - match */
+		return 1;
+
+	/* comm is truncated, but first 15 chars match.
+	 * This can be crazily_long_script_name.sh!
+	 * The telltale sign is basename(argv[1]) == procName. */
+
+	if (!p->argv0)
+		return 0;
+
+	argv1idx = strlen(p->argv0) + 1;
+	if (argv1idx >= p->argv_len)
+		return 0;
+
+	if (strcmp(bb_basename(p->argv0 + argv1idx), procName) != 0)
+		return 0;
+
+	return 1;
+}
+
 /* find_pid_by_name()
  *
  *  Modified by Vladimir Oleynik for use with libbb/procps.c
@@ -48,24 +77,20 @@ and therefore comm field contains "exe".
  *  Returns a list of all matching PIDs
  *  It is the caller's duty to free the returned pidlist.
  */
-pid_t* FAST_FUNC find_pid_by_name(const char* procName)
+pid_t* FAST_FUNC find_pid_by_name(const char *procName)
 {
 	pid_t* pidList;
 	int i = 0;
 	procps_status_t* p = NULL;
 
-	pidList = xmalloc(sizeof(*pidList));
-	while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGV0))) {
-		if (
-		/* we require comm to match and to not be truncated */
-		/* in Linux, if comm is 15 chars, it may be a truncated
-		 * name, so we don't allow that to match */
-		    (!p->comm[sizeof(p->comm)-2] && strcmp(p->comm, procName) == 0)
+	pidList = xzalloc(sizeof(*pidList));
+	while ((p = procps_scan(p, PSSCAN_PID|PSSCAN_COMM|PSSCAN_ARGVN))) {
+		if (comm_match(p, procName)
 		/* or we require argv0 to match (essential for matching reexeced /proc/self/exe)*/
 		 || (p->argv0 && strcmp(bb_basename(p->argv0), procName) == 0)
 		/* TOOD: we can also try /proc/NUM/exe link, do we want that? */
 		) {
-			pidList = xrealloc(pidList, sizeof(*pidList) * (i+2));
+			pidList = xrealloc_vector(pidList, 2, i);
 			pidList[i++] = p->pid;
 		}
 	}
diff --git a/libbb/procps.c b/libbb/procps.c
index a5168a0..f799099 100644
--- a/libbb/procps.c
+++ b/libbb/procps.c
@@ -78,7 +78,7 @@ const char* FAST_FUNC get_cached_groupname(gid_t gid)
 
 #define PROCPS_BUFSIZE 1024
 
-static int FAST_FUNC read_to_buf(const char *filename, void *buf)
+static int read_to_buf(const char *filename, void *buf)
 {
 	int fd;
 	/* open_read_close() would do two reads, checking for EOF.
@@ -385,16 +385,15 @@ procps_status_t* FAST_FUNC procps_scan(procps_status_t* sp, int flags)
 			n = read_to_buf(filename, buf);
 			if (n <= 0)
 				break;
-#if ENABLE_PGREP || ENABLE_PKILL
 			if (flags & PSSCAN_ARGVN) {
-				do {
-					n--;
-					if (buf[n] == '\0')
-						buf[n] = ' ';
-				} while (n);
+				sp->argv_len = n;
+				sp->argv0 = xmalloc(n + 1);
+				memcpy(sp->argv0, buf, n + 1);
+				/* sp->argv0[n] = '\0'; - buf has it */
+			} else {
+				sp->argv_len = 0;
+				sp->argv0 = xstrdup(buf);
 			}
-#endif
-			sp->argv0 = xstrdup(buf);
 		}
 #endif
 		break;