//roardl.c:

/*
 *      Copyright (C) Philipp 'ph3-der-loewe' Schafft - 2010-2011
 *
 *  This file is part of libroar a part of RoarAudio,
 *  a cross-platform sound system for both, home and professional use.
 *  See README for details.
 *
 *  This file is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License version 3
 *  as published by the Free Software Foundation.
 *
 *  libroar is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this software; see the file COPYING.  If not, write to
 *  the Free Software Foundation, 51 Franklin Street, Fifth Floor,
 *  Boston, MA 02110-1301, USA.
 *
 *  NOTE for everyone want's to change something and send patches:
 *  read README and HACKING! There a addition information on
 *  the license of this document you need to read before you send
 *  any patches.
 *
 *  NOTE for uses of non-GPL (LGPL,...) software using libesd, libartsc
 *  or libpulse*:
 *  The libs libroaresd, libroararts and libroarpulse link this lib
 *  and are therefore GPL. Because of this it may be illigal to use
 *  them with any software that uses libesd, libartsc or libpulse*.
 */

#include "libroar.h"

#if defined(ROAR_HAVE_LIBDL) && !defined(RTLD_NEXT)
#define RTLD_NEXT ((void *) -1L)
#endif

struct roar_dl_lhandle {
 struct roar_dl_librarypara * para;
 struct roar_dl_libraryinst * lib;
#if defined(ROAR_HAVE_LIBDL)
 void * handle;
#endif
};


struct roar_dl_librarypara * roar_dl_para_new(const char * args, void * binargv,
                                              const char * appname, const char * abiversion) {
 struct roar_dl_librarypara * ret = roar_mm_malloc(sizeof(struct roar_dl_librarypara));
 ssize_t argc;
 int err;

 if ( ret == NULL )
  return NULL;

 memset(ret, 0, sizeof(struct roar_dl_librarypara));

 ret->version    = ROAR_DL_LIBPARA_VERSION;
 ret->len        = sizeof(struct roar_dl_librarypara);
 ret->refc       = 1;
 ret->argc       = 0;
 ret->argv       = NULL;
 ret->args_store = NULL;
 ret->binargv    = binargv;
 ret->appname    = appname;
 ret->abiversion = abiversion;

 if ( args != NULL ) {
  ret->args_store = roar_mm_strdup(args);
  if ( ret->args_store == NULL ) {
   err = roar_error;
   roar_mm_free(ret);
   roar_error = err;
   return NULL;
  }

  argc = roar_keyval_split(&(ret->argv), ret->args_store, NULL, NULL, 0);
  if ( argc == -1 ) {
   err = roar_error;
   roar_mm_free(ret->args_store);
   roar_mm_free(ret);
   roar_error = err;
   return NULL;
  }

  ret->argc = argc;
 }

 return ret;
}

int roar_dl_para_ref                    (struct roar_dl_librarypara * para) {
 if ( para == NULL ) {
  roar_err_set(ROAR_ERROR_FAULT);
  return -1;
 }

 para->refc++;

 return 0;
}

int roar_dl_para_unref                  (struct roar_dl_librarypara * para) {
 if ( para == NULL ) {
  roar_err_set(ROAR_ERROR_FAULT);
  return -1;
 }

 para->refc--;

 if ( para->refc == 0 ) {
  if ( para->args_store != NULL ) {
   roar_mm_free(para->args_store);
   roar_mm_free(para->argv);
  }
  roar_mm_free(para);
 }

 return 0;
}
int roar_dl_para_check_version          (struct roar_dl_librarypara * para,
                                         const char * appname, const char * abiversion) {
 if ( para == NULL ) {
  roar_err_set(ROAR_ERROR_FAULT);
  return -1;
 }

 // check if both appnames are NULL or non-NULL.
 if ( (para->appname == NULL && appname != NULL) || (para->appname != NULL && appname == NULL) ) {
  roar_err_set(ROAR_ERROR_BADVERSION);
  return -1;
 }

 // check if the appname matches if given.
 if ( para->appname != NULL && !!strcmp(para->appname, appname) ) {
  roar_err_set(ROAR_ERROR_BADVERSION);
  return -1;
 }

 // check if both ABI versions are NULL or non-NULL.
 if ( (para->abiversion == NULL && abiversion != NULL) || (para->abiversion != NULL && abiversion == NULL) ) {
  roar_err_set(ROAR_ERROR_BADVERSION);
  return -1;
 }

 // check if the ABI versions matches if given.
 if ( para->abiversion != NULL && !!strcmp(para->abiversion, abiversion) ) {
  roar_err_set(ROAR_ERROR_BADVERSION);
  return -1;
 }

 return 0;
}


#if defined(ROAR_HAVE_LIBDL)
static void * _roardl2ldl (struct roar_dl_lhandle * lhandle) {
 if ( lhandle == ROAR_DL_HANDLE_DEFAULT )
  return RTLD_DEFAULT;

 if ( lhandle == ROAR_DL_HANDLE_NEXT )
  return RTLD_NEXT;

 return lhandle->handle;
}
#endif

struct roar_dl_lhandle * roar_dl_open(const char * filename, int flags,
                                      int ra_init, struct roar_dl_librarypara * para) {
 struct roar_dl_lhandle * ret = NULL;
 int err;

 // early errors just return.

 if ( flags != ROAR_DL_FLAG_DEFAUTS ) {
  roar_err_set(ROAR_ERROR_NOTSUP);
  return NULL;
 }

 if ( (ret = roar_mm_malloc(sizeof(struct roar_dl_lhandle))) == NULL )
  return NULL;

 memset(ret, 0, sizeof(struct roar_dl_lhandle));

#if defined(ROAR_HAVE_LIBDL)
 flags  = RTLD_NOW;

#ifdef RTLD_DEEPBIND
 flags |= RTLD_DEEPBIND;
#endif

 ret->handle = dlopen(filename, flags);

 if ( ret->handle == NULL ) {
  roar_mm_free(ret);
  return NULL;
 }
#else
 roar_mm_free(ret);
 roar_err_set(ROAR_ERROR_NOSYS);
 return NULL;
#endif

 ret->para = para;

 if ( ra_init ) {
  if ( roar_dl_ra_init(ret, NULL, para) == -1 ) {
   err = roar_error;
   ROAR_WARN("roar_dl_open(filename='%s', flags=%i, ra_init=%i, para=%p): Can not init RA lib: %s", filename, flags, ra_init, para, roar_error2str(err));
#if defined(ROAR_HAVE_LIBDL)
   dlclose(ret->handle);
#endif
   roar_mm_free(ret);
   roar_error = err;
   return NULL;
  }
 }

 if ( para != NULL )
  roar_dl_para_ref(para);

 return ret;
}

int                      roar_dl_close(struct roar_dl_lhandle * lhandle) {
 int ret = -1;

 if ( lhandle == ROAR_DL_HANDLE_DEFAULT || lhandle == ROAR_DL_HANDLE_NEXT ) {
  roar_err_set(ROAR_ERROR_BADFH);
  return -1;
 }

 if ( lhandle->lib != NULL && lhandle->lib->unload != NULL )
  lhandle->lib->unload(lhandle->para, lhandle->lib);

#if defined(ROAR_HAVE_LIBDL)
 ret = dlclose(_roardl2ldl(lhandle));
#else
 ret = -1;
#endif

 if ( lhandle->para != NULL )
  roar_dl_para_unref(lhandle->para);

 roar_mm_free(lhandle);

 return ret;
}

void                   * roar_dl_getsym(struct roar_dl_lhandle * lhandle, const char * sym, int type) {
#if defined(ROAR_HAVE_LIBDL)
 void * ret = dlsym(_roardl2ldl(lhandle), sym);

 (void)type;

 ROAR_DBG("roar_dl_getsym(lhandle=%p, sym='%s', type=%i) = %p", lhandle, sym, type, ret);

 return ret;
#else
 return NULL;
#endif
}

int                      roar_dl_ra_init(struct roar_dl_lhandle * lhandle,
                                         const char * prefix,
                                         struct roar_dl_librarypara * para) {
#define _SUFFIX "_roaraudio_library_init"
 char name[80] = _SUFFIX;
 struct roar_dl_libraryinst * (*func)(struct roar_dl_librarypara * para);
 struct roar_dl_libraryinst * lib;
 int i;

 if ( (void*)lhandle < (void*)128 ) {
  if ( prefix == NULL )
   return -1;
 } else {
  if ( para == NULL )
   para = lhandle->para;
 }


 if ( prefix != NULL ) {
  roar_mm_strscpy(name, "_");
  roar_mm_strscat(name, prefix);
  roar_mm_strscat(name, _SUFFIX);
 }

 ROAR_DBG("roar_dl_ra_init(lhandle=%p, prefix='%s'): name='%s'", lhandle, prefix, name);

 if ( (func = roar_dl_getsym(lhandle, name, -1)) == NULL )
  return -1;

 ROAR_DBG("roar_dl_ra_init(lhandle=%p, prefix='%s'): func=%p", lhandle, prefix, func);

 lib = func(para);

 if ( lib == NULL )
  return -1;

 if ( lib->version != ROAR_DL_LIBINST_VERSION )
  return -1;

 if ( sizeof(struct roar_dl_libraryinst) > lib->len )
  return -1;

 if ( !((void*)lhandle < (void*)128) ) {
  lhandle->lib = lib;
 }

 for (i = 0; i < ROAR_DL_FN_MAX; i++) {
  if ( lib->func[i] != NULL )
   lib->func[i](para, lib);
 }

 return 0;
}

const char * roar_dl_errstr(struct roar_dl_lhandle * lhandle) {
#if defined(ROAR_HAVE_LIBDL)
 (void)lhandle;
 return dlerror();
#else
 return NULL;
#endif
}

struct roar_dl_librarypara       * roar_dl_getpara(struct roar_dl_lhandle * lhandle) {
 if ( (void*)lhandle < (void*)128 ) {
  roar_err_set(ROAR_ERROR_NOTSUP);
  return NULL;
 }

 if ( lhandle->para == NULL ) {
  roar_err_set(ROAR_ERROR_NOENT);
  return NULL;
 }

 if ( roar_dl_para_ref(lhandle->para) == -1 )
  return NULL;

 return lhandle->para;
}

const struct roar_dl_libraryname * roar_dl_getlibname(struct roar_dl_lhandle * lhandle) {
 if ( (void*)lhandle < (void*)128 ) {
  roar_err_set(ROAR_ERROR_NOTSUP);
  return NULL;
 }

 if ( lhandle->lib == NULL ) {
  roar_err_set(ROAR_ERROR_BADLIB);
  return NULL;
 }

 if ( lhandle->lib->libname == NULL ) {
  roar_err_set(ROAR_ERROR_NOENT);
  return NULL;
 }

 if ( lhandle->lib->libname->version != ROAR_DL_LIBNAME_VERSION ) {
  roar_err_set(ROAR_ERROR_BADVERSION);
  return NULL;
 }

 if ( lhandle->lib->libname->len != sizeof(struct roar_dl_libraryname) ) {
  roar_err_set(ROAR_ERROR_HOLE);
  return NULL;
 }

 return lhandle->lib->libname;
}

//ll