/*
 * These routines were taken from the Apache source, but were made
 * available with a PostgreSQL-compatible license.	Kudos Wilfredo
 * Sánchez <wsanchez@apple.com>.
 *
 * $Header: /cvsroot/pgsql/src/backend/port/dynloader/darwin.c,v 1.6 2002/10/01 05:06:44 tgl Exp $
 */

#include "postgres.h"
#include <mach-o/dyld.h>
#include "dynloader.h"

void *
pg_dlopen(char *filename)
{
	NSObjectFileImage image;

	if (NSCreateObjectFileImageFromFile(filename, &image) !=
		NSObjectFileImageSuccess)
		return NULL;
	return NSLinkModule(image, filename,
			    NSLINKMODULE_OPTION_BINDNOW |
			    NSLINKMODULE_OPTION_RETURN_ON_ERROR);
}

void
pg_dlclose(void *handle)
{
	NSUnLinkModule(handle, FALSE);
	return;
}

PGFunction
pg_dlsym(void *handle, char *funcname)
{
	NSSymbol	symbol;
	char	   *symname = (char *) malloc(strlen(funcname) + 2);

	sprintf(symname, "_%s", funcname);
	if (NSIsSymbolNameDefined(symname))
	{
		symbol = NSLookupAndBindSymbol(symname);
		free(symname);
		return (PGFunction) NSAddressOfSymbol(symbol);
	}
	else
	{
		free(symname);
		return (PGFunction) NULL;
	}
}

char *
pg_dlerror(void)
{
	return "no error message available";
}
