Merge pull request #1801 from KriSchu/feature_check_disk_add_ignore_missing_option

check_disk: add ignore-missing option to return OK for missing fs

4 files changed, 135 insertions, 24 deletions

diff --git a/lib/utils_disk.c b/lib/utils_disk.c
index 4f16068..468769b 100644
--- a/lib/utils_disk.c
+++ b/lib/utils_disk.c
@@ -47,9 +47,10 @@ np_add_parameter(struct parameter_list **list, const char *name)
   struct parameter_list *current = *list;
   struct parameter_list *new_path;
   new_path = (struct parameter_list *) malloc (sizeof *new_path);
-  new_path->name = (char *) name;
+  new_path->name = (char *) malloc(strlen(name) + 1);
   new_path->best_match = NULL;
   new_path->name_next = NULL;
+  new_path->name_prev = NULL;
   new_path->freespace_bytes = NULL;
   new_path->freespace_units = NULL;
   new_path->freespace_percent = NULL;
@@ -75,13 +76,17 @@ np_add_parameter(struct parameter_list **list, const char *name)
   new_path->dused_inodes_percent = 0;
   new_path->dfree_inodes_percent = 0;
 
+  strcpy(new_path->name, name);
+
   if (current == NULL) {
     *list = new_path;
+    new_path->name_prev = NULL;
   } else {
     while (current->name_next) {
       current = current->name_next;
     }
     current->name_next = new_path;
+    new_path->name_prev = current;
   }
   return new_path;
 }
@@ -90,6 +95,9 @@ np_add_parameter(struct parameter_list **list, const char *name)
 struct parameter_list *
 np_del_parameter(struct parameter_list *item, struct parameter_list *prev)
 {
+  if (item == NULL) {
+    return NULL;
+  }
   struct parameter_list *next;
 
   if (item->name_next)
@@ -97,10 +105,17 @@ np_del_parameter(struct parameter_list *item, struct parameter_list *prev)
   else
     next = NULL;
 
-  free(item);
+  if (next)
+    next->name_prev = prev;
+
   if (prev)
     prev->name_next = next;
 
+  if (item->name) {
+    free(item->name);
+  }
+  free(item);
+
   return next;
 }
 
diff --git a/lib/utils_disk.h b/lib/utils_disk.h
index bf52e4c..3b5a45f 100644
--- a/lib/utils_disk.h
+++ b/lib/utils_disk.h
@@ -24,6 +24,7 @@ struct parameter_list
   char *group;
   struct mount_entry *best_match;
   struct parameter_list *name_next;
+  struct parameter_list *name_prev;
   uintmax_t total, available, available_to_root, used,
     inodes_free, inodes_free_to_root, inodes_used, inodes_total;
   double dfree_pct, dused_pct;
diff --git a/plugins/check_disk.c b/plugins/check_disk.c
index 935acce..bd84c82 100644
--- a/plugins/check_disk.c
+++ b/plugins/check_disk.c
@@ -112,11 +112,12 @@ enum
 {
   SYNC_OPTION = CHAR_MAX + 1,
   NO_SYNC_OPTION,
-  BLOCK_SIZE_OPTION
+  BLOCK_SIZE_OPTION,
+  IGNORE_MISSING
 };
 
 #ifdef _AIX
- #pragma alloca
+#pragma alloca
 #endif
 
 int process_arguments (int, char **);
@@ -126,7 +127,7 @@ int validate_arguments (uintmax_t, uintmax_t, double, double, double, double, ch
 void print_help (void);
 void print_usage (void);
 double calculate_percent(uintmax_t, uintmax_t);
-void stat_path (struct parameter_list *p);
+bool stat_path (struct parameter_list *p);
 void get_stats (struct parameter_list *p, struct fs_usage *fsp);
 void get_path_stats (struct parameter_list *p, struct fs_usage *fsp);
 
@@ -140,6 +141,7 @@ int verbose = 0;
 int erronly = FALSE;
 int display_mntp = FALSE;
 int exact_match = FALSE;
+bool ignore_missing = false;
 int freespace_ignore_reserved = FALSE;
 int display_inodes_perfdata = FALSE;
 char *warn_freespace_units = NULL;
@@ -155,6 +157,7 @@ char *crit_usedinodes_percent = NULL;
 char *warn_freeinodes_percent = NULL;
 char *crit_freeinodes_percent = NULL;
 int path_selected = FALSE;
+bool path_ignored = false;
 char *group = NULL;
 struct stat *stat_buf;
 struct name_list *seen = NULL;
@@ -166,10 +169,12 @@ main (int argc, char **argv)
   int result = STATE_UNKNOWN;
   int disk_result = STATE_UNKNOWN;
   char *output;
+  char *ignored;
   char *details;
   char *perf;
   char *perf_ilabel;
-  char *preamble;
+  char *preamble = " - free space:";
+  char *ignored_preamble = " - ignored paths:";
   char *flag_header;
   int temp_result;
 
@@ -181,8 +186,8 @@ main (int argc, char **argv)
   char mountdir[32];
 #endif
 
-  preamble = strdup (" - free space:");
   output = strdup ("");
+  ignored = strdup ("");
   details = strdup ("");
   perf = strdup ("");
   perf_ilabel = strdup ("");
@@ -203,7 +208,7 @@ main (int argc, char **argv)
   /* If a list of paths has not been selected, find entire
      mount list and create list of paths
    */
-  if (path_selected == FALSE) {
+  if (path_selected == FALSE && path_ignored == false) {
     for (me = mount_list; me; me = me->me_next) {
       if (! (path = np_find_parameter(path_select_list, me->me_mountdir))) {
         path = np_add_parameter(&path_select_list, me->me_mountdir);
@@ -213,17 +218,40 @@ main (int argc, char **argv)
       set_all_thresholds(path);
     }
   }
-  np_set_best_match(path_select_list, mount_list, exact_match);
+
+  if (path_ignored == false) {
+    np_set_best_match(path_select_list, mount_list, exact_match);
+  }
 
   /* Error if no match found for specified paths */
   temp_list = path_select_list;
 
-  while (temp_list) {
-    if (! temp_list->best_match) {
-      die (STATE_CRITICAL, _("DISK %s: %s not found\n"), _("CRITICAL"), temp_list->name);
+  while (path_select_list) {
+    if (! path_select_list->best_match && ignore_missing == true) {
+      /* If the first element will be deleted, the temp_list must be updated with the new start address as well */
+      if (path_select_list == temp_list) {
+        temp_list = path_select_list->name_next;
+      }
+      /* Add path argument to list of ignored paths to inform about missing paths being ignored and not alerted */
+      xasprintf (&ignored, "%s %s;", ignored, path_select_list->name);
+      /* Delete the path from the list so that it is not stat-checked later in the code. */
+      path_select_list = np_del_parameter(path_select_list, path_select_list->name_prev);
+    } else if (! path_select_list->best_match) {
+      /* Without --ignore-missing option, exit with Critical state. */
+      die (STATE_CRITICAL, _("DISK %s: %s not found\n"), _("CRITICAL"), path_select_list->name);
+    } else {
+      /* Continue jumping through the list */
+      path_select_list = path_select_list->name_next;
     }
+  }
+
+  path_select_list = temp_list;
 
-    temp_list = temp_list->name_next;
+  if (! path_select_list && ignore_missing == true) {
+    result = STATE_OK;
+    if (verbose >= 2) {
+      printf ("None of the provided paths were found\n");
+    }
   }
 
   /* Process for every path in list */
@@ -242,6 +270,10 @@ main (int argc, char **argv)
 
     me = path->best_match;
 
+    if (!me) {
+      continue;
+    }
+
 #ifdef __CYGWIN__
     if (strncmp(path->name, "/cygdrive/", 10) != 0 || strlen(path->name) > 11)
         continue;
@@ -260,8 +292,12 @@ main (int argc, char **argv)
     if (path->group == NULL) {
       /* Skip remote filesystems if we're not interested in them */
       if (me->me_remote && show_local_fs) {
-        if (stat_remote_fs)
-          stat_path(path);
+        if (stat_remote_fs) {
+          if (!stat_path(path) && ignore_missing == true) {
+              result = STATE_OK;
+              xasprintf (&ignored, "%s %s;", ignored, path->name);
+          }
+        }
         continue;
       /* Skip pseudo fs's if we haven't asked for all fs's */
       } else if (me->me_dummy && !show_all_fs) {
@@ -280,7 +316,13 @@ main (int argc, char **argv)
       }
     }
 
-    stat_path(path);
+    if (!stat_path(path)) {
+      if (ignore_missing == true) {
+        result = STATE_OK;
+        xasprintf (&ignored, "%s %s;", ignored, path->name);
+      }
+      continue;
+    }
     get_fs_usage (me->me_mountdir, me->me_devname, &fsp);
 
     if (fsp.fsu_blocks && strcmp ("none", me->me_mountdir)) {
@@ -411,8 +453,12 @@ main (int argc, char **argv)
   if (verbose >= 2)
     xasprintf (&output, "%s%s", output, details);
 
+  if (strcmp(output, "") == 0 && ! erronly) {
+    preamble = "";
+    xasprintf (&output, " - No disks were found for provided parameters;");
+  }
 
-  printf ("DISK %s%s%s|%s\n", state_text (result), (erronly && result==STATE_OK) ? "" : preamble, output, perf);
+  printf ("DISK %s%s%s%s%s|%s\n", state_text (result), ((erronly && result==STATE_OK)) ? "" : preamble, output, (strcmp(ignored, "") == 0) ? "" : ignored_preamble, ignored, perf);
   return result;
 }
 
@@ -481,6 +527,7 @@ process_arguments (int argc, char **argv)
     {"ignore-ereg-partition", required_argument, 0, 'i'},
     {"ignore-eregi-path", required_argument, 0, 'I'},
     {"ignore-eregi-partition", required_argument, 0, 'I'},
+    {"ignore-missing", no_argument, 0, IGNORE_MISSING},
     {"local", no_argument, 0, 'l'},
     {"stat-remote-fs", no_argument, 0, 'L'},
     {"iperfdata", no_argument, 0, 'P'},
@@ -632,12 +679,19 @@ process_arguments (int argc, char **argv)
       /* add parameter if not found. overwrite thresholds if path has already been added  */
       if (! (se = np_find_parameter(path_select_list, optarg))) {
           se = np_add_parameter(&path_select_list, optarg);
+
+          if (stat(optarg, &stat_buf[0]) && ignore_missing == true) {
+            path_ignored = true;
+            break;
+          }
       }
       se->group = group;
       set_all_thresholds(se);
 
       /* With autofs, it is required to stat() the path before re-populating the mount_list */
-      stat_path(se);
+      if (!stat_path(se)) {
+        break;
+      }
       /* NB: We can't free the old mount_list "just like that": both list pointers and struct
        * pointers are copied around. One of the reason it wasn't done yet is that other parts
        * of check_disk need the same kind of cleanup so it'd better be done as a whole */
@@ -718,6 +772,9 @@ process_arguments (int argc, char **argv)
       cflags = default_cflags;
       break;
 
+    case IGNORE_MISSING:
+      ignore_missing = true;
+      break;
     case 'A':
       optarg = strdup(".*");
           // Intentional fallthrough
@@ -753,7 +810,11 @@ process_arguments (int argc, char **argv)
         }
       }
 
-      if (!fnd)
+      if (!fnd && ignore_missing == true) {
+        path_ignored = true;
+        /* path_selected = TRUE;*/
+        break;
+      } else if (!fnd)
         die (STATE_UNKNOWN, "DISK %s: %s - %s\n",_("UNKNOWN"),
             _("Regular expression did not match any path or disk"), optarg);
 
@@ -923,6 +984,9 @@ print_help (void)
   printf ("    %s\n", _("Regular expression to ignore selected path/partition (case insensitive) (may be repeated)"));
   printf (" %s\n", "-i, --ignore-ereg-path=PATH, --ignore-ereg-partition=PARTITION");
   printf ("    %s\n", _("Regular expression to ignore selected path or partition (may be repeated)"));
+  printf (" %s\n", "--ignore-missing");
+  printf ("    %s\n", _("Return OK if no filesystem matches, filesystem does not exist or is inaccessible."));
+  printf ("    %s\n", _("(Provide this option before -p / -r / --ereg-path if used)"));
   printf (UT_PLUG_TIMEOUT, DEFAULT_SOCKET_TIMEOUT);
   printf (" %s\n", "-u, --units=STRING");
   printf ("    %s\n", _("Choose bytes, kB, MB, GB, TB (default: MB)"));
@@ -956,7 +1020,7 @@ print_usage (void)
   printf ("[-t timeout] [-u unit] [-v] [-X type] [-N type]\n");
 }
 
-void
+bool
 stat_path (struct parameter_list *p)
 {
   /* Stat entry to check that dir exists and is accessible */
@@ -965,9 +1029,14 @@ stat_path (struct parameter_list *p)
   if (stat (p->name, &stat_buf[0])) {
     if (verbose >= 3)
       printf("stat failed on %s\n", p->name);
-    printf("DISK %s - ", _("CRITICAL"));
-    die (STATE_CRITICAL, _("%s %s: %s\n"), p->name, _("is not accessible"), strerror(errno));
+    if (ignore_missing == true) {
+      return false;
+    } else {
+      printf("DISK %s - ", _("CRITICAL"));
+      die (STATE_CRITICAL, _("%s %s: %s\n"), p->name, _("is not accessible"), strerror(errno));
+    }
   }
+  return true;
 }
 
 
@@ -987,7 +1056,8 @@ get_stats (struct parameter_list *p, struct fs_usage *fsp) {
         continue;
 #endif
       if (p_list->group && ! (strcmp(p_list->group, p->group))) {
-        stat_path(p_list);
+        if (! stat_path(p_list))
+          continue;
         get_fs_usage (p_list->best_match->me_mountdir, p_list->best_match->me_devname, &tmpfsp);
         get_path_stats(p_list, &tmpfsp);
         if (verbose >= 3)
diff --git a/plugins/t/check_disk.t b/plugins/t/check_disk.t
index ec527e7..c8f08f5 100644
--- a/plugins/t/check_disk.t
+++ b/plugins/t/check_disk.t
@@ -23,7 +23,7 @@ my $mountpoint2_valid = getTestParameter( "NP_MOUNTPOINT2_VALID", "Path to anoth
 if ($mountpoint_valid eq "" or $mountpoint2_valid eq "") {
         plan skip_all => "Need 2 mountpoints to test";
 } else {
-        plan tests => 78;
+        plan tests => 88;
 }
 
 $result = NPTest->testCmd( 
@@ -351,3 +351,28 @@ unlike( $result->output, qr/$mountpoint2_valid/, "output data does not have $mou
 $result = NPTest->testCmd( "./check_disk -w 0% -c 0% -p $mountpoint_valid -p $mountpoint2_valid -i '^barbazJodsf\$'");
 like( $result->output, qr/$mountpoint_valid/, "ignore: output data does have $mountpoint_valid when regex doesn't match");
 like( $result->output, qr/$mountpoint2_valid/,"ignore: output data does have $mountpoint2_valid when regex doesn't match");
+
+# ignore-missing: exit okay, when fs is not accessible
+$result = NPTest->testCmd( "./check_disk --ignore-missing -w 0% -c 0% -p /bob");
+cmp_ok( $result->return_code, '==', 0, "ignore-missing: return okay for not existing filesystem /bob");
+like( $result->output, '/^DISK OK - No disks were found for provided parameters; - ignored paths: /bob;.*$/', 'Output OK');
+
+# ignore-missing: exit okay, when regex does not match
+$result = NPTest->testCmd( "./check_disk --ignore-missing -w 0% -c 0% -r /bob");
+cmp_ok( $result->return_code, '==', 0, "ignore-missing: return okay for regular expression not matching");
+like( $result->output, '/^DISK OK - No disks were found for provided parameters;.*$/', 'Output OK');
+
+# ignore-missing: exit okay, when fs with exact match (-E) is not found
+$result = NPTest->testCmd( "./check_disk --ignore-missing -w 0% -c 0% -E -p /etc");
+cmp_ok( $result->return_code, '==', 0, "ignore-missing: return okay when exact match does not find fs");
+like( $result->output, '/^DISK OK - No disks were found for provided parameters; - ignored paths: /etc;.*$/', 'Output OK');
+
+# ignore-missing: exit okay, when checking one existing fs and one non-existing fs (regex)
+$result = NPTest->testCmd( "./check_disk --ignore-missing -w 0% -c 0% -r '/bob' -r '^/\$'");
+cmp_ok( $result->return_code, '==', 0, "ignore-missing: return okay for regular expression not matching");
+like( $result->output, '/^DISK OK - free space: \/ .*$/', 'Output OK');
+
+# ignore-missing: exit okay, when checking one existing fs and one non-existing fs (path)
+$result = NPTest->testCmd( "./check_disk --ignore-missing -w 0% -c 0% -p '/bob' -p '/'");
+cmp_ok( $result->return_code, '==', 0, "ignore-missing: return okay for regular expression not matching");
+like( $result->output, '/^DISK OK - free space: / .*; - ignored paths: /bob;.*$/', 'Output OK');
\ No newline at end of file