Megatest

;;     You should have received a copy of the GNU General Public License
;;     along with Megatest.  If not, see <http://www.gnu.org/licenses/>.

;;======================================================================

(declare (unit commonmod))
(declare (uses debugprint))
(declare (uses mtargs))
(declare (uses stml2))

(use srfi-69)

(module commonmod
	*

(import scheme)
(cond-expand
 (chicken-4
  
  (import chicken
	  ports
	  (prefix base64 base64:)
	  

	  (prefix sqlite3 sqlite3:)
	  data-structures
	  extras
	  files
	  matchable
	  md5
	  message-digest
	  pathname-expand
	  posix
	  posix-extras
	  regex
	  regex-case
	  sparse-vectors
	  srfi-1
	  srfi-13
	  srfi-18
	  srfi-69
	  typed-records
	  z3

	  
	  debugprint
	  stml2
	  (prefix mtargs args:)
	  )
  (use srfi-69))
 (chicken-5
  (import (prefix sqlite3 sqlite3:)
	  ;; data-structures
	  ;; extras
	  ;; files

	 (currtime (current-seconds)))
    (if (> (- currtime lasttime) waitval)
	(begin
	  (hash-table-set! *common:denoise* key currtime)
	  #t)
	#f)))

;; GLOBALS

;; CONTEXTS
(defstruct cxt
  (taskdb #f)
  (cmutex (make-mutex)))
;; (define *contexts* (make-hash-table))
;; (define *context-mutex* (make-mutex))

;; ;; safe method for accessing a context given a toppath
;; ;;
;; (define (common:with-cxt toppath proc)
;;   (mutex-lock! *context-mutex*)
;;   (let ((cxt (hash-table-ref/default *contexts* toppath #f)))
;;     (if (not cxt)
;;         (set! cxt (let ((x (make-cxt)))(hash-table-set! *contexts* toppath x) x)))
;;     (let ((cxt-mutex (cxt-mutex cxt)))
;;       (mutex-unlock! *context-mutex*)
;;       (mutex-lock! cxt-mutex)
;;       (let ((res (proc cxt)))
;;         (mutex-unlock! cxt-mutex)
;;         res))))
        
;; A hash table that can be accessed by #{scheme ...} calls in
;; config files. Allows communicating between confgs
;;
(define *user-hash-data* (make-hash-table))

(define *db-keys* #f)

(define *pkts-info*    (make-hash-table)) ;; store stuff like the last parent here
(define *configinfo*   #f)   ;; raw results from setup, includes toppath and table from megatest.config
(define *runconfigdat* #f)   ;; run configs data
(define *configdat*    #f)   ;; megatest.config data
(define *configstatus* #f)   ;; status of data; 'fulldata : all processing done, #f : no data yet, 'partialdata : partial read done
;; (define *toppath*      #f) ;; moved to commonmod
(define *already-seen-runconfig-info* #f)

(define *test-meta-updated* (make-hash-table))
(define *globalexitstatus*  0) ;; attempt to work around possible thread issues
(define *passnum*           0) ;; when running track calls to run-tests or similar
;; (define *alt-log-file* #f)  ;; used by -log
;; (define *common:denoise*    (make-hash-table)) ;; for low noise printing
(define *time-zero* (current-seconds)) ;; for the watchdog
(define *on-exit-procs* '()) ;; add procs to this list to be executed on exit
(define *default-area-tag* "local")

;; DATABASE
;; task db
(define *task-db*             #f) ;; (vector db path-to-db)
(define *db-access-allowed*   #t) ;; flag to allow access
;; (define *db-access-mutex*     (make-mutex)) ;; moved to dbfile
;; (define *db-transaction-mutex* (make-mutex))
(define *db-cache-path*       #f)
;; (define *db-with-db-mutex*    (make-mutex))
(define *db-api-call-time*    (make-hash-table)) ;; hash of command => (list of times)

;; SERVER
(define *transport-type*    'http)             ;; override with [server] transport http|rpc|nmsg
(define *runremote*         #f)                ;; if set up for server communication this will hold <host port>
;; (define *max-cache-size*    0)
(define *logged-in-clients* (make-hash-table))
(define *server-id*         #f)
;; (define *server-info*       #f)  ;; good candidate for easily convert to non-global
(define *time-to-exit*      #f)
(define *run-id*            #f)
(define *server-kind-run*   (make-hash-table))
(define *home-host*         #f)
;; (define *total-non-write-delay* 0)
(define *heartbeat-mutex*   (make-mutex))
;; (define *api-process-request-count* 0)
;; (define *max-api-process-requests* 0)
(define *server-overloaded*  #f)

;; client
(define *rmt-mutex*         (make-mutex))     ;; remote access calls mutex 

;; RPC transport
(define *rpc:listener*      #f)

;; KEY info
(define *target*            (make-hash-table)) ;; cache the target here; target is keyval1/keyval2/.../keyvalN
(define *keys*              (make-hash-table)) ;; cache the keys here
(define *keyvals*           (make-hash-table))
(define *toptest-paths*     (make-hash-table)) ;; cache toptest path settings here
(define *test-paths*        (make-hash-table)) ;; cache test-id to test run paths here
(define *test-ids*          (make-hash-table)) ;; cache run-id, testname, and item-path => test-id
(define *test-info*         (make-hash-table)) ;; cache the test info records, update the state, status, run_duration etc. from testdat.db

(define *run-info-cache*     (make-hash-table)) ;; run info is stable, no need to reget
(define *launch-setup-mutex* (make-mutex))     ;; need to be able to call launch:setup often so mutex it and re-call the real deal only if *toppath* not set
(define *homehost-mutex*     (make-mutex))

;; Miscellaneous
(define *triggers-mutex*     (make-mutex))     ;; block overlapping processing of triggers
(define *numcpus-cache* (make-hash-table))

;; this plugs a hole in posix-extras in recent chicken versions > 4.9)
(let-values (( (chicken-release-number chicken-major-version)
               (apply values
                      (map string->number
                           (take
                            (string-split (chicken-version) ".")
                            2)))))
  (let ((resolve-pathname-broken?
         (or (> chicken-release-number 4)
             (and (eq? 4 chicken-release-number) (> chicken-major-version 9)))))
    (if resolve-pathname-broken?
        (define ##sys#expand-home-path pathname-expand))))
      
(define (realpath x) (resolve-pathname  (pathname-expand (or x "/dev/null")) ))

(define (common:get-this-exe-fullpath #!key (argv (argv)))
  (let* ((this-script
          (cond
           ((and (> (length argv) 2)
                 (string-match "^(.*/csi|csi)$" (car argv))
                 (string-match "^-(s|ss|sx|script)$" (cadr argv)))
            (caddr argv))
           (else (car argv))))
         (fullpath (realpath this-script)))
    fullpath))

;;======================================================================

(define *common:this-exe-fullpath* (common:get-this-exe-fullpath))
(define *common:this-exe-dir*      (pathname-directory *common:this-exe-fullpath*))
(define *common:this-exe-name*     (pathname-strip-directory *common:this-exe-fullpath*))

(define (common:get-sync-lock-filepath)
  (let* ((tmp-area     (common:make-tmpdir-name *toppath* ""))
         (lockfile     (conc tmp-area "/megatest.db.lock")))
    lockfile))

(define *common:logpro-exit-code->status-sym-alist*
  '( ( 0 . pass )
     ( 1 . fail )
     ( 2 . warn )
     ( 3 . check )
     ( 4 . waived )
     ( 5 . abort )
     ( 6 . skip )))

(define (common:logpro-exit-code->status-sym exit-code)
  (or (alist-ref exit-code *common:logpro-exit-code->status-sym-alist*) 'fail))

(define (common:worse-status-sym ss1 ss2)
  (let loop ((status-syms-remaining '(abort fail check skip warn waived pass)))
    (cond
     ((null? status-syms-remaining)
      'fail)
     ((eq? (car status-syms-remaining) ss1)
      ss1)
     ((eq? (car status-syms-remaining) ss2)
      ss2)
     (else
      (loop (cdr status-syms-remaining))))))

(define (common:steps-can-proceed-given-status-sym status-sym)
  (if (member status-sym '(warn waived pass))
      #t
      #f))

(define (status-sym->string status-sym)
  (case status-sym
      ((pass) "PASS")
    ((fail) "FAIL")
    ((warn) "WARN")
    ((check) "CHECK")
    ((waived) "WAIVED")
    ((abort) "ABORT")
    ((skip) "SKIP")
    (else "FAIL")))

(define (common:logpro-exit-code->test-status exit-code)
  (status-sym->string (common:logpro-exit-code->status-sym exit-code)))

;; launching and hosts
(defstruct host
  (reachable    #f)
  (last-update  0)
  (last-used    0)
  (last-cpuload 1))

(define *host-loads*         (make-hash-table))

;; cache environment vars for each run here
(define *env-vars-by-run-id* (make-hash-table))

;; Testconfig and runconfig caches. 
(define *testconfigs*        (make-hash-table)) ;; test-name => testconfig
(define *runconfigs*         (make-hash-table)) ;; target    => runconfig

;; This is a cache of pre-reqs met, don't re-calc in cases where called with same params less than
;; five seconds ago
(define *pre-reqs-met-cache* (make-hash-table))

;; cache of verbosity given string
;;
(define *verbosity-cache*    (make-hash-table))

(define (common:clear-caches)
  (set! *target*             (make-hash-table))
  (set! *keys*               (make-hash-table))
  (set! *keyvals*            (make-hash-table))
  (set! *toptest-paths*      (make-hash-table))
  (set! *test-paths*         (make-hash-table))
  (set! *test-ids*           (make-hash-table))
  (set! *test-info*          (make-hash-table))
  (set! *run-info-cache*     (make-hash-table))
  (set! *env-vars-by-run-id* (make-hash-table))
  (set! *test-id-cache*      (make-hash-table)))

;; Generic string database
(define sdb:qry #f) ;; (make-sdb:qry)) ;;  'init #f)
;; Generic path database
(define *fdb* #f)

(define *last-launch* (current-seconds)) ;; use for throttling the launch rate. Would be better to use the db and last time of a test in LAUNCHED state.

;; environment vars handy stuff from common.scm
;;
(define getenv get-environment-variable)
(define (safe-setenv key val)
  (if (or (substring-index "!" key)
	  (substring-index ":" key)  ;; variables containing : are for internal use and cannot be environment variables.
	  (substring-index "." key)) ;; periods are not allowed in environment variables

     (string->number (read-line)))))

;; get the normalized (i.e. load / numcpus) for *this* host
;;
(define (get-normalized-cpu-load)
  (/ (commonmod:get-cpu-load)(get-current-host-cores)))

;;======================================================================
;; testsuite and area utilites
;;======================================================================

(define (get-testsuite-name toppath configdat)
  (or (lookup configdat "setup" "area-name")
      (lookup configdat "setup" "testsuite")
      (get-environment-variable "MT_TESTSUITE_NAME")
      (if (string? toppath)
          (pathname-file toppath)
          #f)))

(define (get-area-path-signature toppath #!optional (short #f))
  (let ((res (message-digest-string (md5-primitive) toppath)))
    (if short
	(substring res 0 4)
	res)))

(define (get-area-name configdat toppath #!optional (short #f))
  ;; look up my area name in areas table (future)
  ;; generate auto name
  (conc (get-area-path-signature toppath short)
	"-"
	(get-testsuite-name toppath configdat)))

;; need generic find-record-with-var-nmatching-val
;;
(define (path->area-record cfgdat path)
  (let* ((areadat (get-cfg-areas cfgdat))
	 (all     (filter (lambda (x)
			    (let* ((keyvals (cdr x))
				   (pth     (alist-ref 'path keyvals)))
			      (equal? path pth)))
			  areadat)))
    (if (null? all)
	#f
	(car all)))) ;; return first match

;; given a config return an alist of alists
;;   area-name => data
;;
(define (get-cfg-areas cfgdat)
  (let ((adat (get-section cfgdat "areas")))
    (map (lambda (entry)
	   `(,(car entry) . 
	     ,(val->alist (cadr entry))))
	 adat)))

;;======================================================================
;; time utils
;;======================================================================

(define (common:human-time)
  (time->string (seconds->local-time (current-seconds)) "%Y-%m-%d %H:%M:%S"))

    (length (glob (conc "/proc/" pid "/fd/*")))
    (length  (filter identity (map socket? (glob (conc "/proc/" pid "/fd/*")))))
  )
)

  

;; GLOBALS

;; CONTEXTS
(defstruct cxt
  (taskdb #f)
  (cmutex (make-mutex)))
;; (define *contexts* (make-hash-table))
;; (define *context-mutex* (make-mutex))

;; ;; safe method for accessing a context given a toppath
;; ;;
;; (define (common:with-cxt toppath proc)
;;   (mutex-lock! *context-mutex*)
;;   (let ((cxt (hash-table-ref/default *contexts* toppath #f)))
;;     (if (not cxt)
;;         (set! cxt (let ((x (make-cxt)))(hash-table-set! *contexts* toppath x) x)))
;;     (let ((cxt-mutex (cxt-mutex cxt)))
;;       (mutex-unlock! *context-mutex*)
;;       (mutex-lock! cxt-mutex)
;;       (let ((res (proc cxt)))
;;         (mutex-unlock! cxt-mutex)
;;         res))))
        
;; A hash table that can be accessed by #{scheme ...} calls in
;; config files. Allows communicating between confgs
;;
(define *user-hash-data* (make-hash-table))

(define *db-keys* #f)

(define *pkts-info*    (make-hash-table)) ;; store stuff like the last parent here
(define *configinfo*   #f)   ;; raw results from setup, includes toppath and table from megatest.config
(define *runconfigdat* #f)   ;; run configs data
(define *configdat*    #f)   ;; megatest.config data
(define *configstatus* #f)   ;; status of data; 'fulldata : all processing done, #f : no data yet, 'partialdata : partial read done
;; (define *toppath*      #f) ;; moved to commonmod
(define *already-seen-runconfig-info* #f)

(define *test-meta-updated* (make-hash-table))
(define *globalexitstatus*  0) ;; attempt to work around possible thread issues
(define *passnum*           0) ;; when running track calls to run-tests or similar
;; (define *alt-log-file* #f)  ;; used by -log
;; (define *common:denoise*    (make-hash-table)) ;; for low noise printing
(define *default-log-port*  (current-error-port))
(define *time-zero* (current-seconds)) ;; for the watchdog
(define *on-exit-procs* '()) ;; add procs to this list to be executed on exit
(define *default-area-tag* "local")

;; DATABASE
;; db access
(define *db-last-access*      (current-seconds)) ;; last db access, used in server
;; (define *db-write-access*     #t)
;; db sync
;; (define *db-last-sync*        0)                 ;; last time the sync to megatest.db happened
(define *db-sync-in-progress* #f)                ;; if there is a sync in progress do not try to start another
;; (define *db-multi-sync-mutex* (make-mutex))      ;; protect access to *db-sync-in-progress*, *db-last-sync*
;; task db
(define *task-db*             #f) ;; (vector db path-to-db)
(define *db-access-allowed*   #t) ;; flag to allow access
;; (define *db-access-mutex*     (make-mutex)) ;; moved to dbfile
;; (define *db-transaction-mutex* (make-mutex))
(define *db-cache-path*       #f)
;; (define *db-with-db-mutex*    (make-mutex))
(define *db-api-call-time*    (make-hash-table)) ;; hash of command => (list of times)

;; SERVER
(define *transport-type*    'http)             ;; override with [server] transport http|rpc|nmsg
(define *runremote*         #f)                ;; if set up for server communication this will hold <host port>
;; (define *max-cache-size*    0)
(define *logged-in-clients* (make-hash-table))
(define *server-id*         #f)
;; (define *server-info*       #f)  ;; good candidate for easily convert to non-global
(define *time-to-exit*      #f)
(define *run-id*            #f)
(define *server-kind-run*   (make-hash-table))
(define *home-host*         #f)
;; (define *total-non-write-delay* 0)
(define *heartbeat-mutex*   (make-mutex))
;; (define *api-process-request-count* 0)
;; (define *max-api-process-requests* 0)
(define *server-overloaded*  #f)

;; client
(define *rmt-mutex*         (make-mutex))     ;; remote access calls mutex 

;; RPC transport
(define *rpc:listener*      #f)

;; KEY info
(define *target*            (make-hash-table)) ;; cache the target here; target is keyval1/keyval2/.../keyvalN
(define *keys*              (make-hash-table)) ;; cache the keys here
(define *keyvals*           (make-hash-table))
(define *toptest-paths*     (make-hash-table)) ;; cache toptest path settings here
(define *test-paths*        (make-hash-table)) ;; cache test-id to test run paths here
(define *test-ids*          (make-hash-table)) ;; cache run-id, testname, and item-path => test-id
(define *test-info*         (make-hash-table)) ;; cache the test info records, update the state, status, run_duration etc. from testdat.db

(define *run-info-cache*     (make-hash-table)) ;; run info is stable, no need to reget
(define *launch-setup-mutex* (make-mutex))     ;; need to be able to call launch:setup often so mutex it and re-call the real deal only if *toppath* not set
(define *homehost-mutex*     (make-mutex))

;; Miscellaneous
(define *triggers-mutex*     (make-mutex))     ;; block overlapping processing of triggers
(define *numcpus-cache* (make-hash-table))

;; this plugs a hole in posix-extras in recent chicken versions > 4.9)
(let-values (( (chicken-release-number chicken-major-version)
               (apply values
                      (map string->number
                           (take
                            (string-split (chicken-version) ".")
                            2)))))
  (let ((resolve-pathname-broken?
         (or (> chicken-release-number 4)
             (and (eq? 4 chicken-release-number) (> chicken-major-version 9)))))
    (if resolve-pathname-broken?
        (define ##sys#expand-home-path pathname-expand))))
      
(define (realpath x) (resolve-pathname  (pathname-expand (or x "/dev/null")) ))

(define (common:get-this-exe-fullpath #!key (argv (argv)))
  (let* ((this-script
          (cond
           ((and (> (length argv) 2)
                 (string-match "^(.*/csi|csi)$" (car argv))
                 (string-match "^-(s|ss|sx|script)$" (cadr argv)))
            (caddr argv))
           (else (car argv))))
         (fullpath (realpath this-script)))
    fullpath))

;;======================================================================

(define *common:this-exe-fullpath* (common:get-this-exe-fullpath))
(define *common:this-exe-dir*      (pathname-directory *common:this-exe-fullpath*))
(define *common:this-exe-name*     (pathname-strip-directory *common:this-exe-fullpath*))

(define (common:get-sync-lock-filepath)
  (let* ((tmp-area     (common:make-tmpdir-name *toppath* ""))
         (lockfile     (conc tmp-area "/megatest.db.lock")))
    lockfile))

(define *common:logpro-exit-code->status-sym-alist*
  '( ( 0 . pass )
     ( 1 . fail )
     ( 2 . warn )
     ( 3 . check )
     ( 4 . waived )
     ( 5 . abort )
     ( 6 . skip )))

(define (common:logpro-exit-code->status-sym exit-code)
  (or (alist-ref exit-code *common:logpro-exit-code->status-sym-alist*) 'fail))

(define (common:worse-status-sym ss1 ss2)
  (let loop ((status-syms-remaining '(abort fail check skip warn waived pass)))
    (cond
     ((null? status-syms-remaining)
      'fail)
     ((eq? (car status-syms-remaining) ss1)
      ss1)
     ((eq? (car status-syms-remaining) ss2)
      ss2)
     (else
      (loop (cdr status-syms-remaining))))))

(define (common:steps-can-proceed-given-status-sym status-sym)
  (if (member status-sym '(warn waived pass))
      #t
      #f))

(define (status-sym->string status-sym)
  (case status-sym
      ((pass) "PASS")
    ((fail) "FAIL")
    ((warn) "WARN")
    ((check) "CHECK")
    ((waived) "WAIVED")
    ((abort) "ABORT")
    ((skip) "SKIP")
    (else "FAIL")))

(define (common:logpro-exit-code->test-status exit-code)
  (status-sym->string (common:logpro-exit-code->status-sym exit-code)))

;; 
(defstruct remote

  ;; transport to be used
  ;; http              - use http-transport
  ;; http-read-cached  - use http-transport for writes but in-mem cached for reads
  (rmode            'http)
  (hh-dat            (let ((res (or (server:choose-server *toppath* 'homehost)
				    (cons #f #f))))
		       (assert (pair? res)(conc "FATAL: hh-dat should be a pair, got "res))
		       res))
  (server-url        #f) ;; (server:check-if-running *toppath*) #f))
  (server-id         #f)
  (server-info       #f) ;; (if *toppath* (server:check-if-running *toppath*) #f))
  (last-server-check 0)  ;; last time we checked to see if the server was alive
  (connect-time      (current-seconds)) ;; when we first connected
  (last-access       (current-seconds)) ;; last time we talked to server
  ;; (conndat           #f) ;; iface port api-uri api-url api-req seconds server-id
  (server-timeout    (server:expiration-timeout))
  (force-server      #f)
  (ro-mode           #f)  
  (ro-mode-checked   #f) ;; flag that indicates we have checked for ro-mode

  ;; conndat stuff
  (iface             #f) ;; TODO: Consolidate this data with server-url and server-info above
  (port              #f)
  (api-url           #f)
  (api-uri           #f)
  (api-req           #f))

;; launching and hosts
(defstruct host
  (reachable    #f)
  (last-update  0)
  (last-used    0)
  (last-cpuload 1))

(define *host-loads*         (make-hash-table))

;; cache environment vars for each run here
(define *env-vars-by-run-id* (make-hash-table))

;; Testconfig and runconfig caches. 
(define *testconfigs*        (make-hash-table)) ;; test-name => testconfig
(define *runconfigs*         (make-hash-table)) ;; target    => runconfig

;; This is a cache of pre-reqs met, don't re-calc in cases where called with same params less than
;; five seconds ago
(define *pre-reqs-met-cache* (make-hash-table))

;; cache of verbosity given string
;;
(define *verbosity-cache*    (make-hash-table))

(define (common:clear-caches)
  (set! *target*             (make-hash-table))
  (set! *keys*               (make-hash-table))
  (set! *keyvals*            (make-hash-table))
  (set! *toptest-paths*      (make-hash-table))
  (set! *test-paths*         (make-hash-table))
  (set! *test-ids*           (make-hash-table))
  (set! *test-info*          (make-hash-table))
  (set! *run-info-cache*     (make-hash-table))
  (set! *env-vars-by-run-id* (make-hash-table))
  (set! *test-id-cache*      (make-hash-table)))

;; Generic string database
(define sdb:qry #f) ;; (make-sdb:qry)) ;;  'init #f)
;; Generic path database
(define *fdb* #f)

(define *last-launch* (current-seconds)) ;; use for throttling the launch rate. Would be better to use the db and last time of a test in LAUNCHED state.

;;======================================================================
;; V E R S I O N
;;======================================================================

(define (common:get-full-version)
  (conc megatest-version "-" megatest-fossil-hash))

(define (common:version-signature)
  (conc megatest-version "-" (substring megatest-fossil-hash 0 4)))

;;======================================================================
;; from metadat lookup MEGATEST_VERSION
;;
(define (common:get-last-run-version) ;; RADT => How does this work in send-receive function??; assume it is the value saved in some DB
  (rmt:get-var "MEGATEST_VERSION"))

(define (common:get-last-run-version-number)
  (string->number 
   (substring (common:get-last-run-version) 0 6)))

(define (common:set-last-run-version)
  (rmt:set-var "MEGATEST_VERSION" (common:version-signature)))

;;======================================================================
;; postive number if megatest version > db version
;; negative number if megatest version < db version
(define (common:version-db-delta)
  (- megatest-version (common:get-last-run-version-number)))

(define (common:version-changed?)
  (not (equal? (common:get-last-run-version)
               (common:version-signature))))


;; From 1.70 to 1.80, db's are compatible.

(define (common:api-changed?)
  (let* (
    (megatest-major-version (substring (->string megatest-version) 0 4))
    (run-major-version (substring (conc (common:get-last-run-version)) 0 4))
   )
   (and (not (equal? megatest-major-version "1.80"))
     (not (equal? megatest-major-version megatest-run-version)))
  )
)

;;======================================================================
;; Move me elsewhere ...
;; RADT => Why do we meed the version check here, this is called only if version misma
;;
(define (common:cleanup-db dbstruct #!key (full #f))
  (case (rmt:transport-mode)
    ((http)
     (apply db:multi-db-sync 
	    dbstruct
	    'schema
	    'killservers
	    'adj-target
	    'new2old
	    '(dejunk)
	    ))
    ((tcp nfs)
     (apply db:multi-db-sync 
	    dbstruct
	    'schema
	    'killservers
	    'adj-target
	    'new2old
	    '(dejunk)
	    )))
  (if (common:api-changed?)
      (common:set-last-run-version)))

(define (common:snapshot-file filepath #!key (subdir  ".") )
  (if (file-exists? filepath)
      (let* ((age-sec  (lambda (file)
                         (if (file-exists? file)
                             (- (current-seconds) (file-modification-time file))
                             1000000000))) ;; return really old value if file doesn't exist.  we want to clobber it if old or not exist.
             (ok-flag  #t)

        ;;     copy <file>.hrs.gz <file>.days.gz
        (when (>= (age-wks daysfile) 1)
          (copy daysfile wksfile)
          (copy hrsfile daysfile))
        #t)
      #f))

;;======================================================================
;; Rotate logs, logic: 
;;                 if > 500k and older than 1 week:
;;                     remove previous compressed log and compress this log
;; WARNING: This proc operates assuming that it is in the directory above the
;;          logs directory you wish to log-rotate.
;;
(define (common:rotate-logs)
  (let* ((all-files (make-hash-table))
	 (stats     (make-hash-table))
	 (inc-stat  (lambda (key)
		      (hash-table-set! stats key (+ (hash-table-ref/default stats key 0) 1))))
	(max-allowed (string->number (or (configf:lookup *configdat* "setup" "max-logfiles") "600")))) ;; name -> age
    (if (not (directory-exists? "logs"))(create-directory "logs"))
    (directory-fold 
     (lambda (file rem)
       (handle-exceptions
	exn
	(begin
	  (debug:print-info 2 *default-log-port* "unable to rotate log " file ", probably handled by another process, this is safe to ignore. exn=" exn)
	  (debug:print 2 *default-log-port* " message: " ((condition-property-accessor 'exn 'message) exn))
	  ;; (print-call-chain (current-error-port)) ;; 
	  )
	(let* ((fullname  (conc "logs/" file))
	       (mod-time  (file-modification-time fullname))
	       (file-age  (- (current-seconds) mod-time))
	       (file-old  (> file-age (* 48 60 60)))
	       (file-big  (> (file-size fullname) 200000)))
	  (hash-table-set! all-files file mod-time)
	  (if (or (and (string-match "^.*.log" file)
		       file-old
		       file-big)
		  (and (string-match "^server-.*.log" file)
		       file-old))
	      (let ((gzfile (conc fullname ".gz")))
		(if (common:file-exists? gzfile)
		    (begin
		      (debug:print-info 0 *default-log-port* "removing " gzfile)
		      (delete-file* gzfile)
		      (hash-table-delete!  all-files gzfile) ;; needed?
		      ))
		(debug:print-info 0 *default-log-port* "compressing " file)
		(system (conc "gzip " fullname))
		(inc-stat "gzipped")
		(hash-table-set! all-files (conc file ".gz") file-age)  ;; add the .gz file and remove the base file
		(hash-table-delete! all-files file)
		)
	      (if (and (> file-age (* (string->number (or (configf:lookup *configdat* "setup" "log-expire-days") "30")) 24 3600))
		       (file-exists? fullname)) ;; just in case it was gzipped - will get it next time
		  (handle-exceptions
		   exn
		   #f
		   (if (directory? fullname)
		       (begin
			 (debug:print-info 0 *default-log-port* fullname " in logs directory is a directory! Cannot rotate it, it is best to not put subdirectories in the logs dir.")
			 (inc-stat "directories"))
		       (begin
			 (delete-file* fullname)
			 (inc-stat "deleted")))
		   (hash-table-delete! all-files file)))))))
     '()
     "logs")
    (for-each
     (lambda (category)
       (let ((quant (hash-table-ref/default stats category 0)))
	 (if (> quant 0)
	     (debug:print-info 0 *default-log-port* category " log files: " quant))))
     `("deleted" "gzipped" "directories"))
    (let ((num-logs (hash-table-size all-files)))
      (if (> num-logs max-allowed) ;; because NFS => don't let number of logs exceed 300
	  (let ((files (take (sort (hash-table-keys all-files)
				   (lambda (a b)
				     (< (hash-table-ref all-files a)(hash-table-ref all-files b))))
			     (- num-logs max-allowed))))
	    (for-each
	     (lambda (file)
	       (let* ((fullname (conc "logs/" file)))
		 (if (directory? fullname)
		     (debug:print-info 0 *default-log-port* fullname " in logs directory is a directory! Cannot rotate it, it is best to not put subdirectories in the logs dir.")
		     (handle-exceptions
		      exn
		      (debug:print-error 0 *default-log-port* "failed to remove " fullname ", exn=" exn)
		      (delete-file* fullname)))))
	     files)
	    (debug:print-info 0 *default-log-port* "Deleted " (length files) " files from logs, keeping " max-allowed " files."))))))

;;======================================================================
;; Force a megatest cleanup-db if version is changed and skip-version-check not specified
;; Do NOT check if not on homehost!
;;
(define (common:exit-on-version-changed)
  (if (and *toppath*              ;; do nothing if *toppath* not yet provided
	   (common:on-homehost?))
      (if (common:api-changed?)
	  (let* ((mtconf (conc (get-environment-variable "MT_RUN_AREA_HOME") "/megatest.config"))
                 (dbfile  (conc (get-environment-variable "MT_RUN_AREA_HOME") ".mtdb/main.db"))
                 (read-only (not (file-write-access? dbfile)))
                 (dbstruct (db:setup))) ;; (db:setup-db *dbstruct-dbs* *toppath* #f))) ;;  #t)))
	    (debug:print 0 *default-log-port*
			 "WARNING: Version mismatch!\n"
			 "   expected: " (common:version-signature) "\n"
			 "   got:      " (common:get-last-run-version))
            (cond
             ((get-environment-variable "MT_SKIP_DB_MIGRATE") #t)
             ((and (common:file-exists? mtconf) (common:file-exists? dbfile) (not read-only)
                   (eq? (current-user-id)(file-owner mtconf))) ;; safe to run -cleanup-db
              (debug:print 0 *default-log-port* "   I see you are the owner of megatest.config, attempting to cleanup and reset to new version")
              (handle-exceptions
               exn
               (begin
                 (debug:print 0 *default-log-port* "Failed to switch versions. exn=" exn)
                 (debug:print 0 *default-log-port* " message: " ((condition-property-accessor 'exn 'message) exn))
                 (print-call-chain (current-error-port))
                 (exit 1))
               (common:cleanup-db dbstruct)))
             ((not (common:file-exists? mtconf))
              (debug:print 0 *default-log-port* "   megatest.config does not exist in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             ((not (common:file-exists? dbfile))
              (debug:print 0 *default-log-port* "   .mtdb/main.db does not exist in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             ((not (eq? (current-user-id)(file-owner mtconf)))
              (debug:print 0 *default-log-port* "   You do not own .mtdb/main.db in this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             (read-only
              (debug:print 0 *default-log-port* "   You have read-only access to this area.  Cannot proceed with megatest version migration.")
              (exit 1))
             (else
              (debug:print 0 *default-log-port* " to switch versions you can run: \"megatest -cleanup-db\"")
              (exit 1)))))))
;;======================================================================
;;      (begin
;;	(debug:print 0 *default-log-port* "ERROR: cannot migrate version unless on homehost. Exiting.")
;;	(exit 1))))

;;======================================================================
;; S P A R S E   A R R A Y S
;;======================================================================

(define (make-sparse-array)
  (let ((a (make-sparse-vector)))

  (let ((row (sparse-vector-ref a x)))
    (if row
	(sparse-vector-set! row y val)
	(let ((new-row (make-sparse-vector)))
	  (sparse-vector-set! a x new-row)
	  (sparse-vector-set! new-row y val)))))

;;======================================================================
;; L O C K E R S   A N D   B L O C K E R S 
;;======================================================================

;; block further accesses to databases. Call this before shutting db down
(define (common:db-block-further-queries)
  (mutex-lock! *db-access-mutex*)
  (set! *db-access-allowed* #f)
  (mutex-unlock! *db-access-mutex*))

(define (common:db-access-allowed?)
  (let ((val (begin
	       (mutex-lock! *db-access-mutex*)
	       *db-access-allowed*
	       (mutex-unlock! *db-access-mutex*))))
    val))

;;======================================================================
;; U S E F U L   S T U F F
;;======================================================================

;; convert things to an alist or assoc list, #f gets converted to ""
;;
(define (common:to-alist dat)

  (let ((val (args:get-arg val)))
    (if val val default)))

(define (assoc/default key lst . default)
  (let ((res (assoc key lst)))
    (if res (cadr res)(if (null? default) #f (car default)))))

(define (common:get-testsuite-name)
  (or (configf:lookup *configdat* "setup" "area-name") ;; megatest is a flexible tool, testsuite is too limiting a description.
      (configf:lookup *configdat* "setup" "testsuite" )
      (getenv "MT_TESTSUITE_NAME")
      (pathname-file (or (if (string? *toppath* )
			     (pathname-file *toppath*)
			     #f)
			 (common:get-toppath #f)))
      "please-set-setup-area-name")) ;; (pathname-file (current-directory)))))

;;======================================================================
;; safe getting of toppath
(define (common:get-toppath areapath)
  (or *toppath*
      (if areapath
	  (begin
	    (set! *toppath* areapath)

		(begin
		  (debug:print-error 0 *default-log-port* "Unable to find megatest home directory.")
		  #f)
		(loop (pathname-directory thepath)))))
      ))


;;======================================================================
;; redefine for future cleanup (converge on area-name, the more generic
;;
(define common:get-area-name common:get-testsuite-name)

(define (get-area-path-signature toppath #!optional (short #f))
  (let ((res (message-digest-string (md5-primitive) toppath)))
(define (common:get-db-tmp-area . junk)
  (if *db-cache-path*
    (if short
      *db-cache-path*
      (if *toppath* ;; common:get-create-writeable-dir
	  (handle-exceptions
	      exn
	      (begin
		(debug:print-error 0 *default-log-port* "Couldn't create path to " *db-cache-path* ", exn=" exn)
		(exit 1))
	      (let* ((toppath (common:real-path *toppath*))
		     (tsname (common:get-testsuite-name))
		     (dbpath (common:get-create-writeable-dir
			      (list (conc "/tmp/" (current-user-name)
					  "/megatest_localdb/"
					  tsname "/"
					  (string-translate toppath "/" "."))
	(substring res 0 4)
				    (conc "/tmp/" (current-process-id) ;; just in case we have an issue with the dir by own user name
					  "/"(current-user-name) "/megatest_localdb/"
					  tsname
					  (string-translate toppath "/" "."))
				    ))))
		(set! *db-cache-path* dbpath)
	res)))

		;; ensure megatest area has .mtdb
		(let ((dbarea (conc *toppath* "/.mtdb")))
		  (if (not (file-exists? dbarea))
		      (create-directory dbarea)))
		;; ensure tmp area has .mtdb
		(let ((dbarea (conc dbpath "/.mtdb")))
		  (if (not (file-exists? dbarea))
		      (create-directory dbarea)))
		dbpath))
	  #f)))

(define (common:get-area-path-signature)
  (message-digest-string (md5-primitive) *toppath*))

;;======================================================================
;; E X I T   H A N D L I N G
;;======================================================================

(define (common:run-sync?)
  (and *toppath*               ;; gate if called before *toppath* is set
       (common:on-homehost?)
       (args:get-arg "-server")))


(define (std-signal-handler signum)
  ;; (signal-mask! signum)
  (set! *time-to-exit* #t) 
  ;;(debug:print-info 13 *default-log-port* "got signal "signum)
  (debug:print-error 0 *default-log-port* "Received signal " signum " aaa exiting promptly")
  ;; (std-exit-procedure) ;; shouldn't need this since we are exiting and it will be called anyway
  (exit))

(define (special-signal-handler signum)
  ;; (signal-mask! signum)
  (set! *time-to-exit* #t)
  ;;(debug:print-info 13 *default-log-port* "got signal "signum)
  (debug:print-error 0 *default-log-port* "Received signal " signum " sending email befor exiting!!")
  ;;TODO send email to notify admin contact listed in the config that the lisner got killed
  ;; (std-exit-procedure) ;; shouldn't need this since we are exiting and it will be called anyway
  (exit))


(set-signal-handler! signal/int  std-signal-handler)  ;; ^C
(set-signal-handler! signal/term std-signal-handler)

;; (set-signal-handler! signal/stop std-signal-handler)  ;; ^Z NO, do NOT handle ^Z!

;;======================================================================
;; M I S C   U T I L S
;;======================================================================

;;======================================================================

	     (debug:print-info 10 *default-log-port* "patt " patt " modpatt " modpatt)
	     (if (string-match (regexp modpatt) item)
		 (set! res #t))))
	 (string-split patts ","))
	res)
      #t))

;;======================================================================
;; '(print (string-intersperse (map cadr (hash-table-ref/default (read-config "megatest.config" \#f \#t) "disks" '"'"'("none" ""))) "\n"))'
(define (common:get-disks #!key (configf #f))
  (hash-table-ref/default 
   (or configf (read-config "megatest.config" #f #t))
   "disks" '("none" "")))

(define (common:get-install-area)
  (let ((exe-path (car (argv))))
    (if (common:file-exists? exe-path)
	(handle-exceptions
	 exn
	 #f
	 (pathname-directory
	  (pathname-directory 
	   (pathname-directory exe-path))))
	#f)))

;;======================================================================
;; return first path that can be created or already exists and is writable
;;
(define (common:get-create-writeable-dir dirs)
  (if (null? dirs)
      #f
      (let loop ((hed (car dirs))

(define (common:list-or-null inlst #!key (ovrd #f)(message #f))
  (if (list? inlst)
      inlst
      (begin
	(if message (debug:print-error 0 *default-log-port* message))
	(or ovrd '()))))
  
;;======================================================================
;; T A R G E T S  ,   S T A T E ,   S T A T U S ,   
;;                    R U N N A M E    A N D   T E S T P A T T
;;======================================================================

;;======================================================================
;; (map print (map car (hash-table->alist (read-config "runconfigs.config" #f #t))))
;;
(define (common:get-runconfig-targets #!key (configf #f))
  (let ((targs       (sort (map car (hash-table->alist
				     (or configf ;; NOTE: There is no value in using runconfig:read here.
					 (read-config (conc *toppath* "/runconfigs.config")
						      #f #t)
					 (make-hash-table))))
			   string<?))
	(target-patt (args:get-arg "-target")))
    (if target-patt
	(filter (lambda (x)
		  (patt-list-match x target-patt))
		targs)
	targs)))

;;======================================================================
;; Lookup a value in runconfigs based on -reqtarg or -target
;; 
(define (runconfigs-get config var)
  (let ((targ (common:args-get-target))) ;; (or (args:get-arg "-reqtarg")(args:get-arg "-target")(getenv "MT_TARGET"))))
    (if targ
	(or (configf:lookup config targ var)
	    (configf:lookup config "default" var))
	(configf:lookup config "default" var))))

(define (common:args-get-state)
  (or (args:get-arg "-state")(args:get-arg ":state")))

(define (common:args-get-status)
  (or (args:get-arg "-status")(args:get-arg ":status")))

(define (common:args-get-testpatt rconf)
  (let* (;; (tagexpr       (args:get-arg "-tagexpr"))
         ;; (tags-testpatt (if tagexpr (string-join (runs:get-tests-matching-tags tagexpr) ",") #f))
         (testpatt-key  (or (args:get-arg "-modepatt") (args:get-arg "--modepatt") "TESTPATT"))
         (args-testpatt (or (args:get-arg "-testpatt") (args:get-arg "-runtests") "%"))
         (rtestpatt     (if rconf (runconfigs-get rconf testpatt-key) #f)))
    (cond
     ((or (args:get-arg "--modepatt") (args:get-arg "-modepatt")) ;; modepatt is a forced setting, when set it MUST refer to an existing PATT in the runconfig
      (if rconf
	  (let* ((patts-from-mode-patt	  (runconfigs-get rconf testpatt-key)))
	    (debug:print-info 0 *default-log-port* "modepatt defined is: "testpatt-key" runconfigs values for  " testpatt-key " "  patts-from-mode-patt)
	    patts-from-mode-patt)
	  (begin
	    (debug:print-info 0 *default-log-port* " modepatt defined is: "testpatt-key" runconfigs values for  " testpatt-key) ;;  " " patts-from-mode-patt)
	    #f)))     ;; We do NOT fall back to "%"
     ;; (tags-testpatt
     ;;  (debug:print-info 0 *default-log-port* "-tagexpr "tagexpr" selects testpatt "tags-testpatt)
     ;;  tags-testpatt)
     ((and (equal? args-testpatt "%") rtestpatt)
      (debug:print-info 0 *default-log-port* "testpatt defined in "testpatt-key" from runconfigs: " rtestpatt)
      rtestpatt)
     (else 
      (debug:print-info 0 *default-log-port* "using testpatt " args-testpatt " rtestpatt:" rtestpatt)
      args-testpatt))))


(define (common:get-linktree)
  (or (getenv "MT_LINKTREE")
      (if *configdat*
	  (configf:lookup *configdat* "setup" "linktree")
	  #f)
      (if (or *toppath* (getenv "MT_RUN_AREA_HOME"))
	  (conc (or *toppath* (getenv "MT_RUN_AREA_HOME")) "/lt")
	  #f)
      (let* ((tp (common:get-toppath #f))
	     (lt (conc tp "/lt")))
	(if (not tp)(debug:print 0 *default-log-port* "WARNING: cannot calculate best path for linktree, using " lt))
	lt)))

(define (common:args-get-runname)
  (let ((res (or (args:get-arg "-runname")
		 (args:get-arg ":runname")
		 (getenv "MT_RUNNAME"))))
    ;; (if res (set-environment-variable "MT_RUNNAME" res)) ;; not sure if this is a good idea. side effect and all ...
    res))

(define (common:get-fields cfgdat)
  (let ((fields (hash-table-ref/default cfgdat "fields" '())))
    (map car fields)))

(define (common:args-get-target #!key (split #f)(exit-if-bad #f))
  (let* ((keys    (if (hash-table? *configdat*) (common:get-fields *configdat*) '()))
	 (numkeys (length keys))
	 (target  (or (args:get-arg "-reqtarg")
		      (args:get-arg "-target")
		      (getenv "MT_TARGET")))
	 (tlist   (if target (string-split target "/" #t) '()))
	 (valid   (if target
		      (or (null? keys) ;; probably don't know our keys yet
			  (and (not (null? tlist))
			       (eq? numkeys (length tlist))
			       (null? (filter string-null? tlist))))
		      #f)))
    (if valid
	(if split
	    tlist
	    target)
	(if target
	    (begin
	      (debug:print-error 0 *default-log-port* "Invalid target, spaces or blanks not allowed \"" target "\", target should be: " (string-intersperse keys "/") ", have " tlist " for elements")
	      (if exit-if-bad (exit 1))
	      #f)
	    #f))))

;;======================================================================
;; looking only (at least for now) at the MT_ variables craft the full testname
;;
(define (common:get-full-test-name)
  (if (getenv "MT_TEST_NAME")
      (if (and (getenv "MT_ITEMPATH")
               (not (equal? (getenv "MT_ITEMPATH") "")))
          (getenv "MT_TEST_NAME")
          (conc (getenv "MT_TEST_NAME") "/" (getenv "MT_ITEMPATH")))
      #f))

;;======================================================================
;; logic for getting homehost. Returns (host . at-home)
;; IF *toppath* is not set, wait up to five seconds trying every two seconds
;; (this is to accomodate the watchdog)
;;

;;======================================================================
;; do we honor the caches of the config files?
;;
(define (common:use-cache?)
  (let ((res #t)) ;; priority by order of evaluation
    (if *configdat* ;; sillyness here. can't use setup/use-cache to know if we can use the cached files!
	(if (equal? (configf:lookup *configdat* "setup" "use-cache") "no")
	    (set! res #f)
	    (if (equal? (configf:lookup *configdat* "setup" "use-cache") "yes")
		(set! res #t))))
    (if (args:get-arg "-no-cache")(set! res #f)) ;; overrides setting in "setup"
    (if (getenv "MT_USE_CACHE")
	(if (equal? (getenv "MT_USE_CACHE") "yes")
	    (set! res #t)
	    (if (equal? (getenv "MT_USE_CACHE") "no")
		(set! res #f))))    ;; overrides -no-cache switch
    res))
  
;;======================================================================
;; force use of server?
;;
(define (common:force-server?)
  (let* ((force-setting (configf:lookup *configdat* "server" "force"))
	 (force-type    (if force-setting (string->symbol force-setting) #f))
	 (force-result  (case force-type
			  ((#f)     #f)
			  ((always) #t)
			  ((test)   (if (args:get-arg "-execute") ;; we are in a test
					#t
					#f))
			  (else
			   (debug:print 0 *default-log-port* "ERROR: Bad server force setting " force-setting ", forcing server.")
			   #t)))) ;; default to requiring server
    (if force-result
	(begin
	  (debug:print-info 0 *default-log-port* "ATTENTION! Forcing use of server, force setting is \"" force-setting "\".")
	  #t)
	#f)))

;;======================================================================
;; M I S C   L I S T S
;;======================================================================

;;======================================================================
;; items in lista are matched value and position in listb

(define (common:get-intercept onemin fivemin)
  (if (< onemin fivemin) ;; load is decreasing, just use the onemin load
      onemin
      (let* ((load-change (- onemin fivemin))
	     (tchange     (- 300 60)))
	(max (+ onemin (* 60 (/ load-change tchange))) 0))))

;;======================================================================
;; calculate a delay number based on a droop curve
;;    inputs are:
;;      - load-in, load as from uptime, NOT normalized
;;      - numcpus, number of cpus, ideally use the real cpus, not threads
;;
(define (common:get-delay load-in numcpus)
  (let* ((ratio (/ load-in numcpus))
         (new-option (configf:lookup *configdat* "load" "new-load-method"))
	 (paramstr   (or (configf:lookup *configdat* "load" "exp-params")
			 "15 12 1281453987.9543 0.75")) ;; 5 4 10 1"))
	 (paramlst   (map string->number (string-split paramstr))))
    (if new-option
	(begin
          (cond ((and (>= ratio 0) (< ratio .5))
		 0)
		((and (>= ratio 0.5) (<= ratio .9))
		 (* ratio (/ 5 .9)))
		((and (> ratio .9) (<= ratio 1.1))
		 (+ 5 (* (- ratio .9) (/ 55 .2)))) 
		((> ratio 1.1)
		 60)))
	(match paramlst
	  ((r1 r2 s1 s2)
	   (debug:print 3 *default-log-port* "Using params r1=" r1 " r2=" r2 " s1=" s1 " s2=" s2)
	   (min (max (/ (expt r1 (* r2 s2 ratio)) s1) 0) 30))
	  (else
	   (debug:print 0 *default-log-port* "BAD exp-params, should be \"r1 r2 s1 s2\" but got " paramstr)
	   30)))))

;; -mrw- this appears to not be used
;;
;; (define (common:print-delay-table)
;;   (let loop ((x 0))
;;     (print x "," (common:get-delay x 1))
;;     (if (< x 2)
;; 	(loop (+ x 0.1)))))

;; (define (get-cpu-load #!key (remote-host #f))
;;    (car (common:get-cpu-load remote-host)))

;;======================================================================
;;   (let* ((load-res (process:cmd-run->list "uptime"))
;; 	 (load-rx  (regexp "load average:\\s+(\\d+)"))
;; 	 (cpu-load #f))
;;     (for-each (lambda (l)
;; 		(let ((match (string-search load-rx l)))
;; 		  (if match
;; 		      (let ((newval (string->number (cadr match))))
;; 			(if (number? newval)
;; 			    (set! cpu-load newval))))))
;; 	      (car load-res))
;;     cpu-load))

;;======================================================================
;; get values from cached info from dropping file in .sysdata dir
;;  e.g. key is host and dtype is normalized-load
;;
(define (common:get-cached-info key dtype #!key (age 10))
  (if *toppath*
      (let* ((fullpath (conc *toppath* "/.sysdata/" key "-" dtype ".log"))

		      ;; (print "NO MATCH: " hed)
		      (loop (car tal)(cdr tal) loads proc-num phys-num core-num)))))))))))

(define (common:unix-ping hostname)
  (let ((res (system (conc "ping -c 1 " hostname " > /dev/null"))))
    (eq? res 0)))

;;======================================================================
;; ideally put all this info into the db, no need to preserve it across moving homehost
;;
;; return list of
;;  ( reachable? cpuload update-time )
(define (common:get-host-info hostname)
  (let* ((loadinfo                         (rmt:get-latest-host-load hostname)) ;; if this host happens to have been recently used by a test reuse the load data
         (load                             (car loadinfo))
         (load-sample-time                 (cdr loadinfo))
         (load-sample-age                  (- (current-seconds) load-sample-time))
         (loadinfo-timeout-seconds         6) ;; this was 20 seconds, seems way too lax. Switch to 6 seconds
         (host-last-update-timeout-seconds 4)
         (host-rec (hash-table-ref/default *host-loads* hostname #f))
         )
    (cond
     ((< load-sample-age loadinfo-timeout-seconds)
      (list #t
            load-sample-time
            load))
     ((and host-rec
           (< (current-seconds) (+ (host-last-update host-rec) host-last-update-timeout-seconds)))
      (list #t
            (host-last-update host-rec)
            (host-last-cpuload host-rec )))
     ((common:unix-ping hostname)
      (list #t
            (current-seconds)
            (alist-ref 'adj-core-load (common:get-normalized-cpu-load hostname)))) ;; this is cheaper than you might think. get-normalized-cpu-load is cached for up to 5 seconds
     (else
      (list #f 0 -1) ;; bad host, don't use!
      ))))

;;======================================================================
;; see defstruct host at top of file.
;;    host: reachable last-update last-used last-cpuload
;;
(define (common:update-host-loads-table hosts-raw)
  (let* ((hosts (filter (lambda (x)
                          (string-match (regexp "^\\S+$") x))
                        hosts-raw)))
    (for-each
     (lambda (hostname)
       (let* ((rec       (let ((h (hash-table-ref/default *host-loads* hostname #f)))
                          (if h
                              h
                              (let ((h (make-host)))
                                (hash-table-set! *host-loads* hostname h)
                                h))))
              (host-info         (common:get-host-info hostname))
              (is-reachable      (car host-info))
              (last-reached-time (cadr host-info))
              (load              (caddr host-info)))
         (host-reachable-set!    rec is-reachable)
         (host-last-update-set!  rec last-reached-time)
         (host-last-cpuload-set! rec load)))
     hosts)))

;;======================================================================
;; go through the hosts from least recently used to most recently used, pick the first that meets the load criteral from the
;; [host-rules] section.
;;
(define (common:get-least-loaded-host hosts-raw host-type configdat)
  (let* ((rdat       (configf:lookup configdat "host-rules" host-type))
	 (rules      (common:val->alist (or rdat "") convert: #t))   ;; maxnload, maxnjobs, maxjobrate
	 (maxnload   (common:alist-ref/default 'maxnload rules 1.5)) ;; max normalized load
	 (maxnjobs   (common:alist-ref/default 'maxnjobs rules 1.5)) ;; max normalized number of jobs
	 (maxjobrate (common:alist-ref/default 'maxjobrate rules (/ 1 6))) ;; max rate of submitting jobs to a given host in jobs/second
	 (hosts      (filter (lambda (x)
			       (string-match (regexp "^\\S+$") x))
			     hosts-raw))
         ;; (best-host #f)
	 (get-rec    (lambda (hostname)
		       ;; (print "get-rec hostname=" hostname)
		       (let ((h (hash-table-ref/default *host-loads* hostname #f)))
			 (if h
			     h
			     (let ((h (make-host)))
			       (hash-table-set! *host-loads* hostname h)
			       h)))))
         (best-load 99999)
         (curr-time (current-seconds))
	 (get-hosts-sorted (lambda (hosts)
			     (sort hosts (lambda (a b)
					   (let ((a-rec (get-rec a))
						 (b-rec (get-rec b)))
					     ;; (print "a=" a " a-rec=" a-rec " host-last-used=" (host-last-used a-rec))
					     ;; (print "b=" b " b-rec=" b-rec " host-last-used=" (host-last-used b-rec))
					     (< (host-last-used a-rec)
						(host-last-used b-rec))))))))
    (debug:print 0 *default-log-port* "INFO: hosts-sorted=" (get-hosts-sorted hosts))
    (if (null? hosts)
	#f ;; no hosts to select from. All done and giving up now.
	(let ((hosts-sorted (get-hosts-sorted hosts)))
	  (common:update-host-loads-table hosts)
	  (let loop ((hostname  (car hosts-sorted))
		     (tal       (cdr hosts-sorted))
		     (best-host #f))
	    (let* ((rec       (get-rec hostname))
		   (reachable (host-reachable     rec))
		   (load      (host-last-cpuload  rec))
		   (last-used (host-last-used     rec))
		   (delta     (- curr-time last-used))
		   (job-rate  (if (> delta 0)
				  (/ 1 delta)
				  999)) ;; jobs per second
		   (new-best  
		    (cond
		     ((not reachable)
		      (debug:print 0 *default-log-port* "Skipping host " hostname " as it cannot be reached.")
		      best-host)
		     ((and (< load maxnload)        ;; load is acceptable
			   (< job-rate maxjobrate)) ;; job rate is acceptable
		      (set! best-load load)
		      hostname)
		     (else best-host))))
	      (debug:print 0 *default-log-port* "INFO: Trying host " hostname " with load " load ", last used " delta " seconds ago, with job-rate " job-rate " for running a test." )
	      (if new-best
		  (begin ;; found a host, return it
		    (debug:print 0 *default-log-port* "INFO: Found host: " new-best " load: " load " last-used: " delta " seconds ago, with job-rate: " job-rate)
		    (host-last-used-set! rec curr-time)
		    new-best)
		  (if (null? tal) #f (loop (car tal)(cdr tal) best-host)))))))))

(define (common:wait-for-homehost-load maxnormload msg)
  (let loop ((start-time (current-seconds))) ;; we saw some instances of this being called before *toppath* was set. This might be an early setup race. This delay should help but it is impossible to test...
    (if (not *toppath*)
	(begin
	  (debug:print 0 *default-log-port* "ERROR: common:wait-for-homehost-load called before *toppath* set.")
	  (thread-sleep! 30)
	  (if (< (- (current-seconds) start-time) 300)
	      (loop start-time)))))
  (case (rmt:transport-mode)
    ((http)
     (let* ((hh-dat (if (common:on-homehost?) ;; if we are on the homehost then pass in #f so the calls are local.
			#f
			(server:choose-server *toppath* 'homehost)))
            (hh     (if hh-dat (car hh-dat) #f)))
       (common:wait-for-normalized-load maxnormload msg hh)))
    (else
     (common:wait-for-normalized-load maxnormload msg (get-host-name)))))
    
(define (common:get-num-cpus remote-host)
  (let* ((actual-host (or remote-host (get-host-name))))
    ;; hosts had better not be changing the number of cpus too often!
    (or (hash-table-ref/default *numcpus-cache* actual-host #f)
	(let* ((numcpus (or (common:get-cached-info actual-host "num-cpus" age: (+ 2592000 (random 3600)))
			    (let* ((proc   (lambda ()
					     (let loop ((numcpu 0)

			      (if (and (number? result)
				       (> result 0))
				  (common:write-cached-info actual-host "num-cpus" result))
			      result))))
	  (hash-table-set! *numcpus-cache* actual-host numcpus)
	  numcpus))))

;;======================================================================
;; wait for normalized cpu load to drop below maxload
;;
(define (common:wait-for-normalized-load maxnormload msg remote-host #!optional (rem-tries 5))
  (let ((num-cpus (common:get-num-cpus remote-host)))
    (if num-cpus
	(common:wait-for-cpuload maxnormload num-cpus 15 msg: msg remote-host: remote-host)
	(begin
	  (thread-sleep! (random 60)) ;; we failed to get num cpus. wait a bit and try again
	  (if (> rem-tries 0)
	      (common:wait-for-normalized-load maxnormload msg remote-host (- rem-tries 1))
	      #f)))))

;;======================================================================
;; DO NOT CALL THIS DIRECTLY. It is called from common:wait-for-normalized-load
;;   count     - count down to zero, at some point we'd give up if the load never drops
;;   num-tries - count down to zero number tries to get numcpus
;;
(define (common:wait-for-cpuload maxnormload numcpus-in
				 #!key (count 1000)
				 (msg #f)(remote-host #f)(num-tries 5))
  (let* ((loadavg     (common:get-cpu-load remote-host))
    ;; not possible to have zero.  If we get 1, it's possible that we got the previous default, and we should check again
    (numcpus     (if (<= 1 numcpus-in)
    (common:get-num-cpus remote-host) numcpus-in))
    (first       (car loadavg))
    (next        (cadr loadavg))
    (adjmaxload  (* maxnormload (max 1 numcpus))) ;; possible bug where numcpus (or could be maxload) is zero, crude
						  ;; fallback is to at least use 1
    ;; effective load accounts for load jumps, this should elminate all the first-next-avg, adjwait, load-jump-limit
    ;; etc.
    (effective-load    (common:get-intercept first next))
    (recommended-delay (common:get-delay effective-load numcpus))
    (effective-host    (or remote-host "localhost"))
    (normalized-effective-load (/ effective-load numcpus))
    (will-wait                 (> normalized-effective-load maxnormload)))
    (if (and will-wait (> recommended-delay 1)) 
      (let* ((actual-delay (min recommended-delay 30)))
        (if (common:low-noise-print 30 (conc (round actual-delay) "-safe-load"))
          (debug:print-info 0 *default-log-port* "Load control, delaying "
				actual-delay " seconds to maintain safe load. current normalized effective load is "
				normalized-effective-load". maxnormload = " maxnormload " numcpus = " numcpus " loadavg = " loadavg " effective-load = " effective-load))
	(thread-sleep! actual-delay)))
    
    (cond
     ;; bad data, try again to get the data
     ((not will-wait)
      (if (common:low-noise-print 3600 (conc (round normalized-effective-load) "-load-acceptable-" effective-host))
      	  (debug:print 0 *default-log-port* "Effective load on " effective-host " is acceptable at " effective-load " continuing.")))

     ((and (< first 0) ;; this indicates the loadavg data is bad - machine may not be reachable
	   (> num-tries 0))
      (debug:print 0 *default-log-port* "WARNING: received bad data from get-cpu-load "
		   first ", we'll sleep 10s and try " num-tries " more times.")
      (thread-sleep! 10)
      (common:wait-for-cpuload maxnormload numcpus-in
			       count: count remote-host: remote-host num-tries: (- num-tries 1)))

     ;; need to wait for load to drop
     ((and will-wait ;; (> first adjmaxload)
	   (> count 0))
      (debug:print-info 0 *default-log-port*
			"Delaying 15" ;; adjwait
			" seconds due to normalized effective load " normalized-effective-load ;; first
			" exceeding max of " adjmaxload
			" on server " (or remote-host (get-host-name))
			" (normalized load-limit: " maxnormload ") " (if msg msg ""))
      (thread-sleep! 15) ;; adjwait)
      (common:wait-for-cpuload maxnormload numcpus count: (- count 1) msg: msg remote-host: remote-host)
      ;; put the message here to indicate came out of waiting
      (debug:print-info 1 *default-log-port*
			"On host: " effective-host
			", effective load: " effective-load
			", numcpus: " numcpus
			", normalized effective load: " normalized-effective-load
			))
     ;; overloaded and count expired (i.e. went to zero)
     (else
      (if (> num-tries 0) ;; should be "num-tries-left". 
	  (if (common:low-noise-print 30 (conc (round effective-load) "-load-acceptable-" effective-host))
	      (debug:print 0 *default-log-port* "Load on " effective-host " is acceptable at effective normalized load of "
			   effective-normalized-load "  continuing."))
	  (debug:print 0 *default-log-port* "Load on " effective-host ", "
		       first" could not be retrieved. Giving up and continuing."))))))

;;======================================================================
;; DO NOT CALL THIS DIRECTLY. It is called from common:wait-for-normalized-load
;;
;; (define (common:wait-for-cpuload maxload-in numcpus-in waitdelay #!key (count 1000) (msg #f)(remote-host #f)(force-maxload #f)(num-tries 5))
;;   (let* ((loadavg (common:get-cpu-load remote-host))
;; 	 (numcpus (if (<= 1 numcpus-in) ;; not possible to have zero.  If we get 1, it's possible that we got the previous default, and we should check again
;; 		      (common:get-num-cpus remote-host)
;; 		      numcpus-in))
;; 	 (maxload (if force-maxload
;; 		      maxload-in
;; 		      (if (number? maxload-in)
;; 			  (max maxload-in 0.5)
;; 			  0.5))) ;; so maxload must be greater than 0.5 for now BUG - FIXME?
;; 	 (first   (car loadavg))
;; 	 (next    (cadr loadavg))
;; 	 (adjmaxload (* maxload (max 1 numcpus))) ;; possible bug where
;; 					       ;; numcpus (or could be
;; 					       ;; maxload) is zero,
;; 					       ;; crude fallback is to
;; 					       ;; at least use 1
;; 	 (loadjmp (- first (if (> next (* numcpus 0.7)) ;; could do something with average of first and next?
;; 			       0
;; 			       next))) ;; we will force a conservative calculation any time next is large.
;; 	 (first-next-avg    (/ (+ first next) 2))
;; 	 ;; add some randomness to the time to break any alignment
;; 	 ;; where netbatch dumps many jobs to machines simultaneously
;;          (adjwait           (min (+ 300 (random 10)) (abs (* (+ (random 10)
;; 								(/ (- 1000 count) 10)
;; 								waitdelay)
;; 							     (- first adjmaxload) ))))
;; 	 (load-jump-limit   (configf:lookup-number *configdat* "setup" "load-jump-limit"))
;; 	 ;; effective load accounts for load jumps, this should elminate all the first-next-avg, adjwait, load-jump-limit
;; 	 ;; etc.
;; 	 (effective-load    (common:get-intercept first next))
;; 	 (effective-host    (or remote-host "localhost"))
;; 	 (normalized-effective-load (/ effective-load numcpus))
;; 	 (will-wait                 (> normalized-effective-load maxload)))
;; 	 
;;     ;; let's let the user know once in a long while that load checking
;;     ;; is happening but not constantly report it
;;     #;(if (common:low-noise-print 30 (conc "cpuload" (or remote-host "localhost"))) ;; (> (random 100) 75) ;; about 25% of the time
;; 	(debug:print-info 1 *default-log-port* "Checking cpuload on " (or remote-host "localhost") ", maxload: " maxload
;;     ", load: " first ", adjmaxload: " adjmaxload ", loadjmp: " loadjmp))
;; 
;;     (debug:print-info 1 *default-log-port*
;; 		      "On host: " effective-host
;; 		      ", effective load: " effective-load
;; 		      ", numcpus: " numcpus
;; 		      ", normalized effective load: " normalized-effective-load
;; 		      )
;;     
;;     (cond
;;      ;; bad data, try again to get the data
;;      ((and (< first 0) ;; this indicates the loadavg data is bad - machine may not be reachable
;; 	   (> num-tries 0))
;;       (debug:print 0 *default-log-port* "WARNING: received bad data from get-cpu-load " first ", we'll sleep 10s and try " num-tries " more times.")
;;       (thread-sleep! 10)
;;       (common:wait-for-cpuload maxload-in numcpus-in waitdelay
;; 			       count: count remote-host: remote-host force-maxload: force-maxload num-tries: (- num-tries 1)))
;;      ;; need to wait for load to drop
;;      ((and will-wait ;; (> first adjmaxload)
;; 	   (> count 0))
;;       (debug:print-info 0 *default-log-port*
;; 			"Delaying " 15 ;; adjwait
;; 			" seconds due to normalized effective load " normalized-effective-load ;; first
;; 			" exceeding max of " adjmaxload
;; 			" on server " (or remote-host (get-host-name))
;; 			" (normalized load-limit: " maxload ") " (if msg msg ""))
;;       (thread-sleep! 15) ;; adjwait)
;;       (common:wait-for-cpuload maxload numcpus waitdelay count: (- count 1) msg: msg remote-host: remote-host))
;;      ((and (> loadjmp (cond
;; 		       (load-jump-limit load-jump-limit)
;; 		       ((> numcpus 8)(/ numcpus 2))
;; 		       ((> numcpus 4)(/ numcpus 1.2))
;; 		       (else 0.5)))
;; 	   (> count 0))
;;       (debug:print-info 0 *default-log-port* "waiting " adjwait " seconds due to possible load jump " loadjmp ". "
;; 			(if msg msg ""))
;;       (thread-sleep! adjwait)
;;       (common:wait-for-cpuload maxload numcpus waitdelay count: (- count 1) msg: msg remote-host: remote-host))
;;      (else
;;       (if (> num-tries 0)
;; 	  (if (common:low-noise-print 30 (conc (round first) "-load-acceptable-" (or remote-host "localhost")))
;; 	      (debug:print 0 *default-log-port* "Load on " (or remote-host "localhost") " is acceptable at " first " continuing."))
;; 	  (debug:print 0 *default-log-port* "Load on " (or remote-host "localhost") ", "first" could not be retrieved. Giving up and continuing."))))))
;; 
(define (get-uname . params)
  (let* ((uname-res (process:cmd-run->list (conc "uname " (if (null? params) "-a" (car params)))))
	 (uname #f))
    (if (null? (car uname-res))
	"unknown"
	(caar uname-res))))

;;======================================================================
;; D I S K   S P A C E 
;;======================================================================

(define (common:get-disk-space-used fpath)
  (with-input-from-pipe (conc "/usr/bin/du -s " fpath) read))

;;======================================================================
;; given path get free space, allows override in [setup]
;; with free-space-script /path/to/some/script.sh
;;
(define (get-df path)
  (if (configf:lookup *configdat* "setup" "free-space-script")
      (with-input-from-pipe 
       (conc (configf:lookup *configdat* "setup" "free-space-script") " " path)
       (lambda ()
	 (let ((res (read-line)))
	   (if (string? res)
	       (string->number res)))))
      (get-unix-df path)))

(define (get-free-inodes path)
  (if (configf:lookup *configdat* "setup" "free-inodes-script")
      (with-input-from-pipe 
	  (conc (configf:lookup *configdat* "setup" "free-inodes-script") " " path)
	(lambda ()
	  (let ((res (read-line)))
	    (if (string? res)
		(string->number res)))))
      (get-unix-inodes path)))

(define (get-unix-df path)
  (let* ((df-results (process:cmd-run->list (conc "df " path)))
	 (space-rx   (regexp "([0-9]+)\\s+([0-9]+)%"))
	 (freespc    #f))
    ;; (write df-results)
    (for-each (lambda (l)
		(let ((match (string-search space-rx l)))
		  (if match 
		      (let ((newval (string->number (cadr match))))
			(if (number? newval)
			    (set! freespc newval))))))
	      (car df-results))
    freespc))

(define (get-unix-inodes path)
  (let* ((df-results (process:cmd-run->list (conc "df -i " path)))
	 (space-rx   (regexp "([0-9]+)\\s+([0-9]+)%"))
	 (freenodes    0)) ;; 0 is a better failsafe than #f here.
    ;; (write df-results)
    (for-each (lambda (l)
		(let ((match (string-search space-rx l)))
		  (if match 
		      (let ((newval (string->number (cadr match))))
			(if (number? newval)
			    (set! freenodes newval))))))
	      (car df-results))
    freenodes))

(define (common:check-space-in-dir dirpath required)
  (let* ((dbspace  (if (directory? dirpath)
		       (get-df dirpath)
		       0)))
    (list (> dbspace required)
	  dbspace
	  required
	  dirpath)))

;;======================================================================
;; check space in dbdir and in megatest dir
;; returns: ok/not dbspace required-space
;;
(define (common:check-db-dir-space)
  (let* ((required (string->number 
                    ;; default is 1GB (or actually a billion bytes) This is the number of 1 kB blocks.
		    (or (configf:lookup *configdat* "setup" "dbdir-space-required")
			"1000000")))
	 (dbdir    (common:make-tmpdir-name *toppath* "")) ;; (db:get-dbdir))
	 (tdbspace (common:check-space-in-dir dbdir required))
	 (mdbspace (common:check-space-in-dir *toppath* required)))
    (sort (list tdbspace mdbspace) (lambda (a b)
				     (< (cadr a)(cadr b))))))

;;======================================================================
;; check available space in dbdir, exit if insufficient
;;
(define (common:check-db-dir-and-exit-if-insufficient)
  (let* ((spacedat (car (common:check-db-dir-space))) ;; look only at worst for now
	 (is-ok    (car spacedat))
	 (dbspace  (cadr spacedat))
	 (required (caddr spacedat))
	 (dbdir    (cadddr spacedat)))
    (if (not is-ok)
	(begin
	  (debug:print-error 0 *default-log-port* "Insufficient space in " dbdir ", require " required ", have " dbspace  ", exiting now.")
	  (exit 1)))))

;;======================================================================
;; paths is list of lists ((name path) ... )
;;
(define (common:get-disk-with-most-free-space disks minsize)
  (let* ((best     #f)
	(bestsize 0)
        (default-min-inodes-string "1000000")
        (default-min-inodes (string->number default-min-inodes-string))
        (min-inodes (or (string->number (if (configf:lookup *configdat* "setup" "min_inodes") (configf:lookup *configdat* "setup" "min_inodes") default-min-inodes-string)) default-min-inodes)))

    (for-each 
     (lambda (disk-num)
       (let* ((dirpath    (cadr (assoc disk-num disks)))
	      (freespc    (cond
			   ((not (directory? dirpath))
			    (if (common:low-noise-print 300 "disks not a dir " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not a directory - ignoring it."))
			    -1)
			   ((not (file-write-access? dirpath))
			    (if (common:low-noise-print 300 "disks not writeable " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not writeable - ignoring it."))
			    -1)
			   ((not (eq? (string-ref dirpath 0) #\/))
			    (if (common:low-noise-print 300 "disks not a proper path " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not a fully qualified path - ignoring it."))
			    -1)
			   (else
			    (get-df dirpath))))
	      (free-inodes (cond
			   ((not (directory? dirpath))
			    (if (common:low-noise-print 300 "disks not a dir " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not a directory - ignoring it."))
			    -1)
			   ((not (file-write-access? dirpath))
			    (if (common:low-noise-print 300 "disks not writeable " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not writeable - ignoring it."))
			    -1)
			   ((not (eq? (string-ref dirpath 0) #\/))
			    (if (common:low-noise-print 300 "disks not a proper path " disk-num)
				(debug:print 0 *default-log-port* "WARNING: disk " disk-num " at path \"" dirpath "\" is not a fully qualified path - ignoring it."))
			    -1)
			   (else
			    (get-free-inodes dirpath))))
             ;;(free-inodes (get-free-inodes dirpath))
             )
             (debug:print 2 *default-log-port* "INFO: disk " disk-num " path " dirpath " free space " freespc " free inodes " free-inodes)
	 (if (and (> freespc bestsize)(> free-inodes min-inodes ))
	     (begin
	       (set! best     (cons disk-num dirpath))
	       (set! bestsize freespc)))
        ;;(print "Processing: " disk-num " bestsize: " bestsize " best: " best " freespc: " freespc " min-inodes: " min-inodes " free-inodes: " free-inodes)
      ))
     (map car disks))
    (if (and best (> bestsize minsize))
	best
	#f))) ;; #f means no disk candidate found

;;======================================================================
;; convert a spec string to a list of vectors #( rx  action rx-string )
(define (common:spec-string->list-of-specs spec-string actions)
  (let ((spec-strings  (string-split-fields "\\s*;\\s*" spec-string #:infix))
	(actions-regex (regexp (conc "^(.*)\\s+(" (string-intersperse (map conc actions) "|") ")"))))
    (filter
     (lambda (x) x)

     (proc          (proc)))
    (hash-table-for-each
     vars
     (lambda (var val)
       (setenv var val)))
    vars))

(define (common:run-a-command cmd #!key (with-vars #f) (with-orig-env #f))
  (let* ((pre-cmd  (dtests:get-pre-command))
         (post-cmd (dtests:get-post-command))
         (fullcmd  (if (or pre-cmd post-cmd)
                       (conc pre-cmd cmd post-cmd)
                       (conc "viewscreen " cmd))))
    (debug:print-info 02 *default-log-port* "Running command: " fullcmd)
    (cond
     (with-vars     (common:without-vars  fullcmd))
     (with-orig-env (common:with-orig-env fullcmd))
     (else          (common:without-vars  fullcmd "MT_.*")))))
		  
;;======================================================================
;; C O L O R S
;;======================================================================
      
(define (common:name->iup-color name)
  (case (string->symbol (string-downcase name))
    ((red)    "223 33 49")

        (map string->number
             (string-split instr)))
   "/"))

;;======================================================================
;; L O C K I N G   M E C H A N I S M S 
;;======================================================================

;;======================================================================
;; faux-lock is deprecated. Please use simple-lock below
;;
(define (common:faux-lock keyname #!key (wait-time 8)(allow-lock-steal #t))
  (if (rmt:no-sync-get/default keyname #f) ;; do not be tempted to compare to pid. locking is a one-shot action, if already locked for this pid it doesn't actually count
      (if (> wait-time 0)
	  (begin
	    (thread-sleep! 1)
	    (if (eq? wait-time 1) ;; only one second left, steal the lock
		(begin
		  (debug:print-info 0 *default-log-port* "stealing lock for " keyname)
		  (common:faux-unlock keyname force: #t)))
	    (common:faux-lock keyname wait-time: (- wait-time 1)))
	  #f)
      (begin
        (rmt:no-sync-set keyname (conc (current-process-id)))
        (equal? (conc (current-process-id)) (conc (rmt:no-sync-get/default keyname #f))))))

(define (common:faux-unlock keyname #!key (force #f))
  (if (or force (equal? (conc (current-process-id)) (conc (rmt:no-sync-get/default keyname #f))))
      (begin
        (if (rmt:no-sync-get/default keyname #f) (rmt:no-sync-del! keyname))
        #t)
      #f))

;;======================================================================
;; simple lock. improve and converge on this one.
;;
(define (common:simple-lock keyname)
  (rmt:no-sync-get-lock keyname))

(define (common:simple-unlock keyname #!key (force #f))
  (rmt:no-sync-del! keyname))

;;======================================================================
;;
;;======================================================================

(define (common:in-running-test?)
  (and (args:get-arg "-execute") (get-environment-variable "MT_CMDINFO")))

;; ;; get registered dashboards
;; ;;
;; (define (mddb:get-dashboards)
;;   (let ((db (mddb:open-db)))
;;     (query fetch-column
;; 	   (sql db "SELECT ipaddr || ':' || portnum FROM dashboards;"))))
    
;;======================================================================
;;  T E S T   L A U N C H I N G   P E R   I T E M   W I T H   H O S T   T Y P E S
;;======================================================================
;; 
;; [hosts]
;; arm cubie01 cubie02
;; x86_64 zeus xena myth01
;; allhosts #{g hosts arm} #{g hosts x86_64}
;; 
;; [host-types]
;; general #MTLOWESTLOAD #{g hosts allhosts}
;; arm     #MTLOWESTLOAD #{g hosts arm}
;; nbgeneral nbjob run JOBCOMMAND -log $MT_LINKTREE/$MT_TARGET/$MT_RUNNAME.$MT_TESTNAME-$MT_ITEM_PATH.lgo
;;
;; [host-rules]
;; # maxnload   => max normalized load
;; # maxnjobs   => max jobs per cpu
;; # maxjobrate => max jobs per second
;; general maxnload=1.1; maxnjobs=1.2; maxjobrate=0.1 
;; 
;; [launchers]
;; envsetup general
;; xor/%/n 4C16G
;; % nbgeneral
;; 
;; [jobtools]
;; # if defined and not "no" flexi-launcher will bypass "launcher" unless no match.
;; flexi-launcher yes  
;; launcher nbfake
;;
(define (common:get-launcher configdat testname itempath)
  (let ((fallback-launcher (configf:lookup configdat "jobtools" "launcher")))
    (if (and (configf:lookup configdat "jobtools" "flexi-launcher") ;; overrides launcher
	     (not (equal? (configf:lookup configdat "jobtools" "flexi-launcher") "no")))
	(let* ((launchers         (hash-table-ref/default configdat "launchers" '())))
	  (if (null? launchers)
	      fallback-launcher
	      (let loop ((hed (car launchers))
			 (tal (cdr launchers)))
		(let ((patt      (car hed))
		      (host-type (cadr hed)))
		  (if (tests:match patt testname itempath)
		      (begin
			(debug:print-info 2 *default-log-port* "Have flexi-launcher match for " testname "/" itempath " = " host-type)
			(let ((launcher (configf:lookup configdat "host-types" host-type)))
			  (if launcher
			      (let* ((launcher-parts (string-split launcher))
				     (launcher-exe   (car launcher-parts)))
				(if (equal? launcher-exe "#MTLOWESTLOAD") ;; this is our special case, we will find the lowest load and craft a nbfake commandline
				    (let host-loop ((targ-host (common:get-least-loaded-host (cdr launcher-parts) host-type configdat))
						    (count     100))
				      (if targ-host
					  (conc "remrun " targ-host)
					  (if (> count 0)
					      (begin
						(debug:print 0 *default-log-port* "INFO: Waiting for a host for host-type " host-type)
						(thread-sleep! (- 101 count))
						(host-loop (common:get-least-loaded-host (cdr launcher-parts) host-type configdat)
							   (- count 1)))
					      (begin
						(debug:print 0 *default-log-port* "FATAL: Failed to find a host from #MTLOWESTLOAD for host-type " host-type)
						(exit)))))
				    launcher))
			      (begin
				(debug:print-info 0 *default-log-port* "WARNING: no launcher found for host-type " host-type)
				(if (null? tal)
				    fallback-launcher
				    (loop (car tal)(cdr tal)))))))
		      ;; no match, try again
		      (if (null? tal)
			  fallback-launcher
			  (loop (car tal)(cdr tal))))))))
	fallback-launcher)))

;;======================================================================
;; D A S H B O A R D   U S E R   V I E W S
;;======================================================================

;;======================================================================
;; first read ~/views.config if it exists, then read $MTRAH/views.config if it exists
;;
(define (common:load-views-config)
  (let* ((view-cfgdat    (make-hash-table))
	 (home-cfgfile   (conc (get-environment-variable "HOME") "/.mtviews.config"))
	 (mthome-cfgfile (conc *toppath* "/.mtviews.config")))
    (if (common:file-exists? mthome-cfgfile)
	(read-config mthome-cfgfile view-cfgdat #t))
    ;; we load the home dir file AFTER the MTRAH file so the user can clobber settings when running the dashboard in read-only areas
    (if (common:file-exists? home-cfgfile)
	(read-config home-cfgfile view-cfgdat #t))
    view-cfgdat))

;;======================================================================
;; H I E R A R C H I C A L   H A S H   T A B L E S
;;======================================================================
;;
;; Every element including top element is a vector:
;;   <vector subhash value>

		(item-path . i)
		(runname   . r)
		(state     . s)
		(target    . t)
		(status    . u)
		(parent    . P)))))

(define (common:get-pkts-dirs mtconf use-lt)
  (let* ((pktsdirs-str (or (configf:lookup mtconf "setup"  "pktsdirs")
			   (and use-lt
				(conc (or *toppath*
					  (current-directory))
				      "/lt/.pkts"))))
	 (pktsdirs  (if pktsdirs-str
			(string-split pktsdirs-str " ")
			#f)))
    pktsdirs))

;;======================================================================
;; use-lt is use linktree "lt" link to find pkts dir
(define (common:save-pkt pktalist-in mtconf use-lt #!key (add-only #f)) ;; add-only saves the pkt only if there is a parent already
  (if (or (not add-only)
	  (hash-table-exists? *pkts-info* 'last-parent))
      (let* ((parent   (hash-table-ref/default *pkts-info* 'last-parent #f))
	     (pktalist (if parent
			   (cons `(parent . ,parent)
				 pktalist-in)
			   pktalist-in)))
	(let-values (((uuid pkt)
		      (alist->pkt pktalist common:pkts-spec)))
	  (hash-table-set! *pkts-info* 'last-parent uuid)
	  (let ((pktsdir (or (hash-table-ref/default *pkts-info* 'pkts-dir #f)
			     (let* ((pktsdirs (common:get-pkts-dirs mtconf use-lt))
				    (pktsdir   (car pktsdirs))) ;; assume it is there
			       (hash-table-set! *pkts-info* 'pkts-dir pktsdir)
			       pktsdir))))
	    (debug:print 0 *default-log-port* "pktsdir: "pktsdir)
            (handle-exceptions
             exn
             (debug:print-info 0 "failed to write out packet to " pktsdir ", exn=" exn) ;; don't care if this failed for now but MUST FIX - BUG!!
             (if (not (file-exists? pktsdir))
                 (create-directory pktsdir #t))
             (with-output-to-file
                 (conc pktsdir "/" uuid ".pkt")
               (lambda ()
                 (print pkt)))))))))
	
(define (common:with-queue-db mtconf proc #!key (use-lt #f)(toppath-in #f))
  (let* ((pktsdirs (common:get-pkts-dirs mtconf use-lt))
	 (pktsdir  (if pktsdirs (car pktsdirs) #f))
	 (toppath  (or (configf:lookup mtconf "scratchdat" "toppath")
		       toppath-in))
	 (pdbpath  (or (configf:lookup mtconf "setup"  "pdbpath") pktsdir)))
    (cond
     ((not (and  pktsdir toppath pdbpath))
      (debug:print 0 *default-log-port* "ERROR: settings are missing in your megatest.config for area management.")
      (debug:print  0 *default-log-port* "  you need to have pktsdirs in the [setup] section."))
     ((not (common:file-exists? pktsdir))
      (debug:print 0 *default-log-port* "ERROR: pkts directory not found " pktsdir))
     ((not (equal? (file-owner pktsdir)(current-effective-user-id)))
      (debug:print 0 *default-log-port* "ERROR: directory " pktsdir " is not owned by " (current-effective-user-name)))
     (else
	(let* ((pdb  (open-queue-db pdbpath "pkts.db"
				    schema: '("CREATE TABLE groups (id INTEGER PRIMARY KEY,groupname TEXT, CONSTRAINT group_constraint UNIQUE (groupname));"))))
	  (proc pktsdirs pktsdir pdb)
	  (dbi:close pdb))))))

(define (common:load-pkts-to-db mtconf #!key (use-lt #f))
  (common:with-queue-db
   mtconf
   (lambda (pktsdirs pktsdir pdb)
     (for-each
      (lambda (pktsdir) ;; look at all
	(cond
	 ((not (common:file-exists? pktsdir))
	  (debug:print 0 *default-log-port* "ERROR: packets directory " pktsdir " does not exist."))
	 ((not (directory? pktsdir))
	  (debug:print 0 *default-log-port* "ERROR: packets directory path " pktsdir " is not a directory."))
	 ((not (file-read-access? pktsdir))
	  (debug:print 0 *default-log-port* "ERROR: packets directory path " pktsdir " is not readable."))
	 (else
	  (debug:print-info 0 *default-log-port* "Loading packets found in " pktsdir)
	  (let ((pkts (glob (conc pktsdir "/*.pkt")))
                (sqdb (dbi:db-conn pdb))
                )
           ;; Put this in a transaction to avoid issues overloading the db
           (sqlite3:with-transaction
            sqdb
            (lambda ()
	    (for-each
	     (lambda (pkt)
	       (let* ((uuid    (cadr (string-match ".*/([0-9a-f]+).pkt" pkt)))
		      (exists  (lookup-by-uuid pdb uuid #f)))
		 (if (not exists)
		     (let* ((pktdat (string-intersperse
				     (with-input-from-file pkt read-lines)
				     "\n"))
			    (apkt   (pkt->alist pktdat))
			    (ptype  (alist-ref 'T apkt)))
		       (add-to-queue pdb pktdat uuid (or ptype 'cmd) #f 0)
		       (debug:print 4 *default-log-port* "Added " uuid " of type " ptype " to queue"))
		     (debug:print 4 *default-log-port* "pkt: " uuid " exists, skipping...")
		     )))
	     pkts)))))))
      pktsdirs))
   use-lt: use-lt))

(define (common:get-pkt-alists pkts)
  (map (lambda (x)
	 (alist-ref 'apkt x)) ;; 'pkta pulls out the alist from the read pkt
       pkts))

;;======================================================================
;; given list of pkts (alist mode) return list of D cards as Unix epoch, sorted descending