commit e3fc76e0ae502fb8ef0aac87eee237db9d9690f5
Author: Jan Safranek <jsafranek@users.sourceforge.net>
Date:   Tue Jul 9 14:26:59 2013 +0200

    CHANGES: snmpd: Make UCD-SNMP::dskTable dynamic if includeAllDisks is set.

diff --git a/agent/mibgroup/ucd-snmp/disk_hw.c b/agent/mibgroup/ucd-snmp/disk_hw.c
index ea37610..f7911d9 100644
--- a/agent/mibgroup/ucd-snmp/disk_hw.c
+++ b/agent/mibgroup/ucd-snmp/disk_hw.c
@@ -55,6 +55,7 @@ static netsnmp_fsys_info ** _expand_disk_array( char *cptr );
 
 int             numdisks;
 int             allDisksIncluded = 0;
+int             allDisksMinPercent = 0;
 int             maxdisks = 0;
 netsnmp_fsys_info **disks = NULL;
 
@@ -119,6 +120,7 @@ init_disk_hw(void)
 				disk_free_config,
 				"minpercent%");
   allDisksIncluded = 0;
+  allDisksMinPercent = 0;
 }
 
 static void
@@ -140,6 +142,7 @@ disk_free_config(void)
      maxdisks = numdisks = 0;
   }
   allDisksIncluded = 0;
+  allDisksMinPercent = 0;
 }
 
 static void 
@@ -199,8 +202,7 @@ static void
 disk_parse_config_all(const char *token, char *cptr)
 {
   int             minpercent = DISKMINPERCENT;
-  netsnmp_fsys_info *entry;
-    
+
   /*
    * read the minimum disk usage percent
    */
@@ -220,30 +222,36 @@ disk_parse_config_all(const char *token, char *cptr)
       netsnmp_config_error("\tignoring: includeAllDisks %s", cptr);
   }
   else {
-
-      netsnmp_fsys_load( NULL, NULL );  /* Prime the fsys H/W module */
-      for ( entry  = netsnmp_fsys_get_first();
-            entry != NULL;
-            entry  = netsnmp_fsys_get_next( entry )) {
-
-          if ( !(entry->flags & NETSNMP_FS_FLAG_ACTIVE ))
-              continue;
-          entry->minspace   = -1;
-          entry->minpercent = minpercent;
-          entry->flags     |= NETSNMP_FS_FLAG_UCD;
-          /*
-           * Ensure there is space for the new entry
-           */
-          if (numdisks == maxdisks) {
-              if (!_expand_disk_array( entry->device )) 
-                  return;
-          }
-          disks[numdisks++] = entry;
-      }
       allDisksIncluded = 1;
+      allDisksMinPercent = minpercent;
   }
 }
 
+/* add new entries to dskTable dynamically */
+static void _refresh_disks(int minpercent)
+{
+    netsnmp_fsys_info *entry;
+
+    for ( entry  = netsnmp_fsys_get_first();
+        entry != NULL;
+        entry  = netsnmp_fsys_get_next( entry )) {
+
+        if (!(entry->flags & NETSNMP_FS_FLAG_UCD)) {
+            /* this is new disk, add it to the table */
+            entry->minspace   = -1;
+            entry->minpercent = minpercent;
+            entry->flags     |= NETSNMP_FS_FLAG_UCD;
+            /*
+             * Ensure there is space for the new entry
+             */
+            if (numdisks == maxdisks) {
+                if (!_expand_disk_array( entry->device ))
+                    return;
+            }
+            disks[numdisks++] = entry;
+        }
+    }
+}
 
 static int _percent( unsigned long long value, unsigned long long total ) {
     float v=value, t=total, pct;
@@ -301,7 +309,7 @@ var_extensible_disk(struct variable *vp,
                     size_t * var_len, WriteMethod ** write_method)
 {
     int             disknum = 0;
-  netsnmp_fsys_info *entry;
+    netsnmp_fsys_info *entry;
     unsigned long long val;
     static long     long_ret;
     static char     errmsg[300];
@@ -310,6 +318,8 @@ var_extensible_disk(struct variable *vp,
     /* Update the fsys H/W module */
     cache = netsnmp_fsys_get_cache();
     netsnmp_cache_check_and_reload(cache);
+    if (allDisksIncluded)
+        _refresh_disks(allDisksMinPercent);
 
 tryAgain:
     if (header_simple_table
@@ -318,9 +328,14 @@ tryAgain:
     disknum = name[*length - 1] - 1;
     entry = disks[disknum];
     if ( !entry ) {
-        if (!exact || !(entry->flags & NETSNMP_FS_FLAG_UCD))
-            goto tryAgain;
-        return NULL;
+        if (exact)
+            return NULL;
+        goto tryAgain;
+    }
+    if (!(entry->flags & NETSNMP_FS_FLAG_ACTIVE) || !(entry->flags & NETSNMP_FS_FLAG_UCD)) {
+        if (exact)
+            return NULL;
+        goto tryAgain;
     }
 
     switch (vp->magic) {
diff --git a/man/snmpd.conf.5.def b/man/snmpd.conf.5.def
index 5f85f72..d2caf9c 100644
--- a/man/snmpd.conf.5.def
+++ b/man/snmpd.conf.5.def
@@ -652,6 +652,8 @@ This requires that the agent was built with support for the
 default build configuration).
 .IP "disk PATH [ MINSPACE | MINPERCENT% ]"
 monitors the disk mounted at PATH for available disk space.
+Disks mounted after the agent has started will not be monitored,
+unless \fIincludeAllDisks\fR option is specified.
 .IP
 The minimum threshold can either be specified in kB (MINSPACE) or
 as a percentage of the total disk (MINPERCENT% with a '%' character),
@@ -668,6 +670,9 @@ the problem - see the DisMan Event MIB section later.
 .IP "includeAllDisks MINPERCENT%"
 configures monitoring of all disks found on the system,
 using the specified (percentage) threshold.
+The \fCdskTable\fR is dynamically updated, unmounted disks
+disappear from the table and newly mounted disks are
+added to the table.
 The threshold for individual disks can be adjusted using suitable
 \fIdisk\fR directives (which can come either before or after the
 \fIincludeAllDisks\fR directive).
@@ -680,12 +685,8 @@ may affect the indexing of the \fCdskTable\fR.
 Only one \fIincludeAllDisks\fR directive should be specified - any
 subsequent copies will be ignored.
 .IP
-The list of mounted disks will be determined when the agent starts using the
-setmntent(3) and getmntent(3), or fopen(3) and getmntent(3),  or
-setfsent(3)  and  getfsent(3) system calls. If none of the above
-system calls are available then the root partition  "/"
-(which  is  assumed to exist on any UNIX based system) will be monitored.
-Disks mounted after the agent has started will not be monitored.
+The list of mounted disks will be determined from
+HOST-RESOURCES-MIB::hrFSTable.
 .\"
 .\" XXX - unless the config is re-read ??
 .\"