Merge branch 'collectd-5.7' into collectd-5.8

Conflicts:
	src/utils_mount.c

diff --cc src/utils_mount.c
Simple merge

diff --cc src/zfs_arc.c
index 55166fa,063c401..6c66fb1
--- 1/src/zfs_arc.c
--- 2/src/zfs_arc.c
+++ b/src/zfs_arc.c
@@@ -229,9 -209,26 +229,26 @@@ static int za_read(void) 
    if (ksp == NULL) {
      ERROR("zfs_arc plugin: `llist_create' failed.");
      fclose(fh);
 -    return (-1);
 +    return -1;
    }
  
+   // Ignore the first two lines because they contain information about
+   // the rest of the file.
+   // See kstat_seq_show_headers module/spl/spl-kstat.c of the spl kernel
+   // module.
+   if (fgets(buffer, sizeof(buffer), fh) == NULL) {
+     ERROR("zfs_arc plugin: \"%s\" does not contain a single line.",
+           ZOL_ARCSTATS_FILE);
+     fclose(fh);
+     return (-1);
+   }
+   if (fgets(buffer, sizeof(buffer), fh) == NULL) {
+     ERROR("zfs_arc plugin: \"%s\" does not contain at least two lines.",
+           ZOL_ARCSTATS_FILE);
+     fclose(fh);
+     return (-1);
+   }
+ 
    while (fgets(buffer, sizeof(buffer), fh) != NULL) {
      char *fields[3];
      value_t v;