fcntl not working proper?

Hello everyone,

I am trying to use sqlite3 which heavily uses fcntl. Attached is my 
source and its compiled nlm. Does anyone have a working sqlite3 ?

The program below fails with "database is locked" which means it
wasn't 
able to put an WRLCK on it. sqlite_debug trace turned out:

fcntl 15 7 SETLK RDLCK 0 1 0 015
fcntl 16 7 SETLK WRLCK 0 1 0 1
fcntl-failure-reason: RDLCK 0 1 0

looks like something went wrong using fcntl.

Testet with sqlite3.c 3.3.17 and 3.4.0.

Thanks in advance

Xatru

/* sqltest.c */
#include <stdio.h>
#include <stdlib.h>
#include "sqlite3.h"

static int callback(void *NotUsed, int argc, char **argv, char **azColName){
   int i;
   for(i=0; i<argc; i++){
     printf("%s = %s\n", azColName[i], argv[i] ? argv[i] :
"NULL");
   }
   printf("\n");
   return 0;
}

int main(int argc, char **argv){
int i;
int rc;
char buf[100];
sqlite3 *sdb;
char *zErrMsg;

zErrMsg=0;

  rc = sqlite3_open("sql.db", &sdb);
   if( rc ){
     consoleprintf("Can't open database: %s\n", sqlite3_errmsg(sdb));
     sqlite3_close(sdb);
     exit(1);
   }

consoleprintf("creating table\n");

   rc = sqlite3_exec(sdb, "CREATE TABLE test (test1 TEXT);", callback,

0, &zErrMsg);
   if( rc!=SQLITE_OK ){
     consoleprintf("SQL error: %s\n", zErrMsg);
     if (zErrMsg)
       free(zErrMsg);
   }

consoleprintf("insert into table\n");

   rc = sqlite3_exec(sdb, "insert into test (test1) values 
('teststring');", callback, 0, &zErrMsg);
   if( rc!=SQLITE_OK ){
     consoleprintf("SQL error: %s\n", zErrMsg);
     if (zErrMsg)
       free(zErrMsg);
   }


consoleprintf("select *\n");

   rc = sqlite3_exec(sdb, "select * from test;", callback, 0,
&zErrMsg);
   if( rc!=SQLITE_OK ){
     consoleprintf("SQL error: %s\n", zErrMsg);
     if (zErrMsg)
       free(zErrMsg);
   }

sqlite3_close(sdb);

return 0;

Hi,

Xatru <xatru@kuehlbox.de> wrote in
news:a_Ddi.3958$%54.1938@prv-forum2.provo.novell.com: 

> Hello everyone,
> 
> I am trying to use sqlite3 which heavily uses fcntl. Attached is my 
> source and its compiled nlm. Does anyone have a working sqlite3 ?
I can confirm that we have a problem with locking on NetWare; I see similar 
with Perl, and also with the php_sqlite extension....
I'd suggest we should work out some simple samples which can nail down the 
prob so that Jeff can take a look into it...
regarding SQLite I have here the code which is used with PHP:
http://www.gknw.net/test/sqlite/
this contains a Makefile which builds the lib + commandline with either 
CodeWarrior or GCC.
Here's a simple flock() sample - something like that is needed to re-create 
the prob:
http://www.gknw.net/test/flock/

G.

Xatru wrote:
> Hello everyone,
> 
> I am trying to use sqlite3 which heavily uses fcntl. Attached is my 
> source and its compiled nlm. Does anyone have a working sqlite3 ?
> 
> The program below fails with "database is locked" which means it
wasn't 
> able to put an WRLCK on it. sqlite_debug trace turned out:
> 
> fcntl 15 7 SETLK RDLCK 0 1 0 015
> fcntl 16 7 SETLK WRLCK 0 1 0 1
> fcntl-failure-reason: RDLCK 0 1 0
> 
> looks like something went wrong using fcntl.
> 
> Testet with sqlite3.c 3.3.17 and 3.4.0.
> 
> Thanks in advance
> 
> Xatru
> 
> /* sqltest.c */
> #include <stdio.h>
> #include <stdlib.h>
> #include "sqlite3.h"
> 
> static int callback(void *NotUsed, int argc, char **argv, char 
> **azColName){
>   int i;
>   for(i=0; i<argc; i++){
>     printf("%s = %s\n", azColName[i], argv[i] ? argv[i] :
"NULL");
>   }
>   printf("\n");
>   return 0;
> }
> 
> int main(int argc, char **argv){
> int i;
> int rc;
> char buf[100];
> sqlite3 *sdb;
> char *zErrMsg;
> 
> zErrMsg=0;
> 
>  rc = sqlite3_open("sql.db", &sdb);
>   if( rc ){
>     consoleprintf("Can't open database: %s\n",
sqlite3_errmsg(sdb));
>     sqlite3_close(sdb);
>     exit(1);
>   }
> 
> consoleprintf("creating table\n");
> 
>   rc = sqlite3_exec(sdb, "CREATE TABLE test (test1 TEXT);",
callback, 0, 
> &zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> consoleprintf("insert into table\n");
> 
>   rc = sqlite3_exec(sdb, "insert into test (test1) values 
> ('teststring');", callback, 0, &zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> 
> consoleprintf("select *\n");
> 
>   rc = sqlite3_exec(sdb, "select * from test;", callback, 0,
&zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> sqlite3_close(sdb);
> 
> return 0;
> }
fcntl for file locking is extremely difficult to implement. Prior to 
leaving Novell, both John Gay and I worked on it, but it was only an 
experimental project and we had no real world test cases. I am now 
familiar with sqlite3 because I use it heavily where I work now (Quest 
Software), but fcntl never became enough of a priority back then for us 
to stress over it (no such use by MySQL, PostGRES, bash, etc.).

Hello.

We have experienced similar problems with sqlite 3.3.16 using
configuration provided by Guenter.

Compilation of command-line shell.nlm with following Makefile changes:

# Global flags for all compilers
CFLAGS	= -nostdinc $(OPT) -D$(DB) -DNETWARE -DN_PLAT_NLM 
-DSQLITE_DEBUG=1 -DSQLITE_LOCK_TRACE
CFLAGS	+= -DOS_UNIX=1

and manually adding in os_common.h file:

int sqlite3_os_trace = 1;

The shell.nlm  test run ended in a hanged console:

fcntl 2 6 SETLK RDLCK 0 1 0 0
fcntl 3 6 SETLK WRLCK 0 1 0 -1
fcntl-failure-reason: RDLCK 0 1 0
OPEN    5   sys:php5/local/test.sq3
READ    5     100       0 0
SQLite version 3.3.16
Enter ".help" for instructions
sqlite>
sqlite> select * from tbl1;
LOCK    5 SHARED was NONE(NONE,0) pid=455
No-transfer, same thread

(hanged ...)

Earlier attempts with less aggressive debug options looked like this:

sqlite> select * from tbl1;
LOCK    5 SHARED was NONE(NONE,0) pid=433
No-transfer, same thread
LOCK    5 SHARED ok
READ    5    1024       0 0
UNLOCK  5 0 was 1(1,1) pid=433
LOCK    5 SHARED was NONE(NONE,0) pid=433
No-transfer, same thread
LOCK    5 SHARED ok
READ    5      16      24 0
READ    5    1024    1024 0
goodbye|20
UNLOCK  5 0 was 1(1,1) pid=433
sqlite> insert into tbl1 values('hello', 10);
LOCK    5 SHARED was NONE(NONE,0) pid=433
No-transfer, same thread
LOCK    5 SHARED ok
READ    5      16      24 0
LOCK    5 RESERVED was SHARED(SHARED,1) pid=433
No-transfer, same thread
TRACE PGAL CODE 006 EAGAIN 5 RESERVED was SHARED(SHARED,1) pid=433
LOCK    5 RESERVED failed
UNLOCK  5 0 was 1(1,1) pid=433
SQL error: database is locked
sqlite>

Piotr


> I am trying to use sqlite3 which heavily uses fcntl. Attached is my 
> source and its compiled nlm. Does anyone have a working sqlite3 ?

> The program below fails with "database is locked" which means it
wasn't 
> able to put an WRLCK on it. sqlite_debug trace turned out:

> fcntl 15 7 SETLK RDLCK 0 1 0 015
> fcntl 16 7 SETLK WRLCK 0 1 0 1
> fcntl-failure-reason: RDLCK 0 1 0

> looks like something went wrong using fcntl.

> Testet with sqlite3.c 3.3.17 and 3.4.0.

Greetings All,
On the face of it, fcntl() and flock() seem to have a lot in common, and 
while checking NetWare Perl issues, found the flock() function in Perl 
to be disabled, and when I asked why, was told there were problems with 
the underlying LibC implementation of that too; perhaps these functions 
share a common LibC code base?
I found flock() (once I activated it in Perl) able to exclusive lock a 
file, but could not 'unlock it for shared access' other than by closing 
it altogether. (This was done on a single-user machine and one file).
Trust this doesn't muddy the water...
Norm.

Xatru wrote:
> Hello everyone,
> 
> I am trying to use sqlite3 which heavily uses fcntl. Attached is my 
> source and its compiled nlm. Does anyone have a working sqlite3 ?
> 
> The program below fails with "database is locked" which means it
wasn't 
> able to put an WRLCK on it. sqlite_debug trace turned out:
> 
> fcntl 15 7 SETLK RDLCK 0 1 0 015
> fcntl 16 7 SETLK WRLCK 0 1 0 1
> fcntl-failure-reason: RDLCK 0 1 0
> 
> looks like something went wrong using fcntl.
> 
> Testet with sqlite3.c 3.3.17 and 3.4.0.
> 
> Thanks in advance
> 
> Xatru
> 
> /* sqltest.c */
> #include <stdio.h>
> #include <stdlib.h>
> #include "sqlite3.h"
> 
> static int callback(void *NotUsed, int argc, char **argv, char 
> **azColName){
>   int i;
>   for(i=0; i<argc; i++){
>     printf("%s = %s\n", azColName[i], argv[i] ? argv[i] :
"NULL");
>   }
>   printf("\n");
>   return 0;
> }
> 
> int main(int argc, char **argv){
> int i;
> int rc;
> char buf[100];
> sqlite3 *sdb;
> char *zErrMsg;
> 
> zErrMsg=0;
> 
>  rc = sqlite3_open("sql.db", &sdb);
>   if( rc ){
>     consoleprintf("Can't open database: %s\n",
sqlite3_errmsg(sdb));
>     sqlite3_close(sdb);
>     exit(1);
>   }
> 
> consoleprintf("creating table\n");
> 
>   rc = sqlite3_exec(sdb, "CREATE TABLE test (test1 TEXT);",
callback, 0, 
> &zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> consoleprintf("insert into table\n");
> 
>   rc = sqlite3_exec(sdb, "insert into test (test1) values 
> ('teststring');", callback, 0, &zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> 
> consoleprintf("select *\n");
> 
>   rc = sqlite3_exec(sdb, "select * from test;", callback, 0,
&zErrMsg);
>   if( rc!=SQLITE_OK ){
>     consoleprintf("SQL error: %s\n", zErrMsg);
>     if (zErrMsg)
>       free(zErrMsg);
>   }
> 
> sqlite3_close(sdb);
> 
> return 0;