[pg-cvs] issue: mmap returns a pointer - osicat-devel - mailman3.common-lisp.net

11 Nov 2009


      Hello osicat-devel
Whilst getting help from John Fremlin for manardb, an issue with osicat arose.  Apparently osicat-posix assumes that the return value from mmap is an int when it is a pointer.  He noted that mremap is broken too.
a backtrace containing the result:
CL-USER> (manardb:use-mmap-dir "/tmp/manardb/" :if-does-not-exist :create)
The value -134270976 is not of type (UNSIGNED-BYTE 64).
   [Condition of type TYPE-ERROR]
Restarts:
 0: [ABORT] Return to SLIME's top level.
 1: [TERMINATE-THREAD] Terminate this thread (#<THREAD "repl-thread" RUNNING {1003249DB1}>)
Backtrace:
  0: (OSICAT-POSIX:MMAP #.(SB-SYS:INT-SAP #X00000000) 4096 3 1 4 0)
  1: (MANARDB::MTAGMAP-OPEN #<MANARDB::MTAGMAP >)[:EXTERNAL]
  2: (MANARDB:OPEN-ALL-MMAPS)
John Fremlin made me fix the bug by evaluating the following code in osicat-posix:
(DEFCFUN ("mmap_cffi_wrap" MMAP :CONVENTION :CDECL :LIBRARY :DEFAULT)
                 (ERRNO-WRAPPER :UNSIGNED-LONG :ERROR-PREDICATE (LAMBDA (P) (= P MAP-FAILED)) :RETURN-FILTER MAKE-POINTER)
                 (START :POINTER)
                 (LENGTH SIZE)
                 (PROT :INT)
                 (FLAGS :INT)
                 (FD FILE-DESCRIPTOR-DESIGNATOR)
                 (OFFSET OFF))
cheers,
the madnificent