i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.

int DB->open(DB *db, DB_TXN *txnid, const char *file,
    const char *database, DBTYPE type, u_int32_t flags, int mode);

my normal approach would be,

extern (C) {
	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
}

but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)

Sun, 30 Aug 2009 11:28:16 -0400, JT wrote:

> i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.
> 
> int DB->open(DB *db, DB_TXN *txnid, const char *file,
>     const char *database, DBTYPE type, u_int32_t flags, int mode);

This is not a valid C or C++ statement, nor a declaration.  It's usually hard to translate an invalid code to a different language.

> my normal approach would be,
> 
> extern (C) {
> 	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
> }

If open() is a method of DB struct then it uses some sort of C++ calling
convention, probably thiscall.  Thiscall is incompatilbe with cdecl, so
extern(C) won't work.

> but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)

I can only guess here that what you want is

extern(C++) interface DB {
    int open(DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode);
}

But, without a link to source you try to bind to, it's only a wild guess.

Sergey Gromov Wrote:

> Sun, 30 Aug 2009 11:28:16 -0400, JT wrote:
> 
> > i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.
> > 
> > int DB->open(DB *db, DB_TXN *txnid, const char *file,
> >     const char *database, DBTYPE type, u_int32_t flags, int mode);
> 
> This is not a valid C or C++ statement, nor a declaration.  It's usually hard to translate an invalid code to a different language.
> 
> > my normal approach would be,
> > 
> > extern (C) {
> > 	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
> > }
> 
> If open() is a method of DB struct then it uses some sort of C++ calling
> convention, probably thiscall.  Thiscall is incompatilbe with cdecl, so
> extern(C) won't work.
> 
> > but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)
> 
> I can only guess here that what you want is
> 
> extern(C++) interface DB {
>     int open(DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode);
> }
> 
> But, without a link to source you try to bind to, it's only a wild guess.

thanks, unfortunately the source is too long to include here, it was a Berkeley DB from Oracle. is there a binding already made for this library. :P

JT wrote:
> i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.
> 
> int DB->open(DB *db, DB_TXN *txnid, const char *file,
>     const char *database, DBTYPE type, u_int32_t flags, int mode);
> 
> my normal approach would be,
> 
> extern (C) {
> 	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
> }
> 
> but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)

The function name is not 'DB->open'. That's something used in the comments. Nearly all functions in Berkeley DB are declared as function pointers used as struct fields. So what you'll want is something like this:

extern(C):

struct DB
{
    int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) open;
}

Along with all of the rest of the DB function pointers and the numerous inner structs declared in the C headers.

Mike Parker Wrote:

> JT wrote:
> > i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.
> > 
> > int DB->open(DB *db, DB_TXN *txnid, const char *file,
> >     const char *database, DBTYPE type, u_int32_t flags, int mode);
> > 
> > my normal approach would be,
> > 
> > extern (C) {
> > 	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
> > }
> > 
> > but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)
> 
> The function name is not 'DB->open'. That's something used in the comments. Nearly all functions in Berkeley DB are declared as function pointers used as struct fields. So what you'll want is something like this:
> 
> extern(C):
> 
> struct DB
> {
>      int function(DB* db, DB_TXN* txnid, char* file, char* database,
> DBTYPE type, u_int32_t flags, int mode) open;
> }
> 
> Along with all of the rest of the DB function pointers and the numerous inner structs declared in the C headers.

thank you so much Mike. yeah i just noticed that.

JT wrote:
> i'm trying to create a binding for berkeley db dll and quickly ran into some problems, how do i translate statement below.
> 
> int DB->open(DB *db, DB_TXN *txnid, const char *file,
>     const char *database, DBTYPE type, u_int32_t flags, int mode);
> 
> my normal approach would be,
> 
> extern (C) {
> 	int function(DB* db, DB_TXN* txnid, char* file, char* database, DBTYPE type, u_int32_t flags, int mode) DB->open;
> }
> 
> but real problem is 'DB->open', can anoybody suggest a workaround for this. DB is just a simple struct (struct DB;)

Maybe this project is interesting. last update may 2007

http://code.google.com/p/db4d/