sqlite defect

[jojelino]

On 2013-07-18 PM 5:59, Corinna Vinschen wrote:> On Jul 18 17:11, 
jojelino wrote:
 >> On 2013-07-18 AM 10:53, Warren Young wrote:
 >>> Nothing so simple.  Locking is handled at the OS and/or Cygwin DLL
 >>> level.  The build change between 3.7.16.2 and 3.7.17-3 is that 
we're now
 >>> relying on new features in the Cygwin DLL to do Windows-style 
locking by
 >>> default.
 >>>
 >>> Older versions of Cygwin SQLite bypassed the Cygwin DLL entirely for
 >>> this, going straight to the Win32 API, thereby preventing the DLL from
 >>> interposing itself for the "posix" case.
 >>>
 >> Mandatory locking feature of cygwin used in sqlite is broken.
 >
 > Simple testcase in plain C?
 >
 >
 > Corinna
 >
#include <stdio.h>
#include <fcntl.h>
#include <assert.h>
#include <string.h>
#include <sys/file.h>
int
main()
{
   int fd = open("asdf.txt", O_BINARY | O_RDWR | O_NOINHERIT | O_CREAT);
   const char* buf = 
"KKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKKK\0";
   int i=0;
   write(fd, buf, strlen(buf));
   fcntl(fd,F_LCK_MANDATORY,0);
   assert(flock(fd,F_SETOWN)==0);
   assert(flock(fd,F_SETOWN)==0);
   assert(flock(fd,LOCK_NB|LOCK_UN)==0);
   fcntl(fd,F_LCK_MANDATORY,1);
   assert(flock(fd,F_SETOWN)==0);
   assert(flock(fd,LOCK_NB|LOCK_UN)==0);
   assert(flock(fd,F_SETOWN)==0);
   assert(flock(fd,F_SETOWN)==0); /* assertion "flock(fd,F_SETOWN)==0" 
failed: file "f_lck.c", line 28, function: main */
   return 0;
}

/**/
-- 
Regards.


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