From: Bart De Vos <bart-de-vos@telenet.be>
Date: Mon, 26 Aug 2019 13:38:12 +0000 (+0200)
Subject: plugin: processes: use a const ref string and strlen i.s.o. magic offset
X-Git-Tag: collectd-5.11.0~8^2~4
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f93354d30a6b0c574f3a09094e1a4982bfd96adf;p=thirdparty%2Fcollectd.git

plugin: processes: use a const ref string and strlen i.s.o. magic offset

The simple parser is based on 'strstr', whereas the actual data does
include a white-space character to separate the 'id' (procs_running)
from the 'value' (a number). Yet parsing the number can off course only
take place 'after' the white-space. Subsequently, not finding a
'white-space' should be treated as an error condition.

Adding the 'white-space' in const string and defining the offset based
on 'strlen' fixes this properly.
---

diff --git a/src/processes.c b/src/processes.c
index f86cd39b1..2cf88a2fe 100644
--- a/src/processes.c
+++ b/src/processes.c
@@ -1431,7 +1431,7 @@ static int ps_read_process(long pid, process_entry_t *ps, char *state) {
 
 static int procs_running(void) {
   char buffer[4096] = {};
-
+  char id[] = "procs_running "; /* white space terminated */
   char *running;
 
   ssize_t status;
@@ -1441,13 +1441,18 @@ static int procs_running(void) {
     return -1;
   }
 
-  running = strstr(buffer, "procs_running");
+  /* the data contains :
+   * the literal string 'procs_running',
+   * a whitespace
+   * the number of running processes.
+   * The parser does include the white-space character.
+   */
+  running = strstr(buffer, id);
   if (!running) {
     WARNING("procs_running not found, assuming 1");
     return 1;
   }
-
-  running += 14;
+  running += strlen(id);
 
   return atoi(running);
 }