source: roaraudio/libroar/roardl.c @ 5438:4eb05969f66c

//roardl.c:

/*
 *      Copyright (C) Philipp 'ph3-der-loewe' Schafft - 2010-2012
 *
 *  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"

#ifdef ROAR_HAVE_H_DIRENT
#include <dirent.h>
#endif

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

struct roar_dl_lhandle {
 size_t refc; // currently unused.
 int flags;
 char * libname; // only used for ROAR_DL_FLAG_STATIC.
 struct roar_dl_librarypara * para;
 struct roar_dl_libraryinst * lib;
 struct {
  struct roar_error_state error_state;
  void *  global_data;
  void *  global_data_state;
  struct roar_notify_core * notifycore;
 } context;
 int ra_inited;
#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_DBG("roar_dl_para_ref(para=%p) = -1 // error=FAULT", para);
  roar_err_set(ROAR_ERROR_FAULT);
  return -1;
 }

 para->refc++;

 ROAR_DBG("roar_dl_para_ref(para=%p) = 0", para);
 return 0;
}

int roar_dl_para_unref                  (struct roar_dl_librarypara * para) {
 if ( para == NULL ) {
  ROAR_DBG("roar_dl_para_unref(para=%p) = -1 // error=FAULT", para);
  roar_err_set(ROAR_ERROR_FAULT);
  return -1;
 }

 para->refc--;

 if ( para->refc ) {
  ROAR_DBG("roar_dl_para_unref(para=%p) = 0", para);
  return 0;
 }

 if ( para->notifycore != NULL )
  roar_notify_core_unref(para->notifycore);

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

 roar_mm_free(para);

 ROAR_DBG("roar_dl_para_unref(para=%p) = 0", 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_BADHOST);
  return -1;
 }

 // check if the appname matches if given.
 if ( para->appname != NULL && !!strcmp(para->appname, appname) ) {
  roar_err_set(ROAR_ERROR_BADHOST);
  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) {
 ROAR_DBG("_roardl2ldl(lhandle=%p) = ?", lhandle);

 if ( lhandle == ROAR_DL_HANDLE_DEFAULT ) {
  ROAR_DBG("_roardl2ldl(lhandle=%p) = %p", lhandle, (void*)RTLD_DEFAULT);
  return RTLD_DEFAULT;
 }

 if ( lhandle == ROAR_DL_HANDLE_NEXT ) {
  ROAR_DBG("_roardl2ldl(lhandle=%p) = %p", lhandle, (void*)RTLD_NEXT);
  return RTLD_NEXT;
 }

 ROAR_DBG("_roardl2ldl(lhandle=%p) = %p", lhandle, (void*)(lhandle->handle));
 return lhandle->handle;
}
#endif

#ifdef ROAR_HAVE_H_DIRENT
// pvn = prefix, host vendor, host name
static struct roar_dl_lhandle * _load_from_path_pvn(const char * name,
                                                    int flags, int ra_init,
                                                    struct roar_dl_librarypara * para,
                                                    const char * prefix,
                                                    const char * hostvendor,
                                                    const char * hostname) {
 struct roar_dl_lhandle * ret = NULL;
 int i, j;
 char path[1024];
 const char * path_format[] = {"%s/%s/%s", "%s/%s/universal", "%s/universal/universal"};
 DIR * dir;
 struct dirent * dirent;
 char file[1024];
 const char * file_format[] = {"%s/%s/%s", "%s/%s/%s" ROAR_SHARED_SUFFIX, "%s/%s/lib%s" ROAR_SHARED_SUFFIX};
//  cont->handle[idx] = roar_dl_open(name, ROAR_DL_FLAG_DEFAULTS, 1, para);
//#vars: $PREFIX_PLUGINS, $hostvendor, $hostname, $name
//#search order: $PREFIX_PLUGINS/{$hostvendor/{$hostname,universal},universal/universal}/*/{,lib}$name.so

 for (i = 0; i < 3; i++) {
  snprintf(path, sizeof(path), path_format[i], prefix, hostvendor, hostname);
  dir = opendir(path);
  if ( dir == NULL )
   continue;

  while ((dirent = readdir(dir)) != NULL) {
   if ( !strcmp(dirent->d_name, ".") || !strcmp(dirent->d_name, "..") )
    continue;

   for (j = 0; j < 3; j++) {
    snprintf(file, sizeof(file), file_format[j], path, dirent->d_name, name);
    ret = roar_dl_open(file, flags, ra_init, para);
    if ( ret != NULL ) {
     closedir(dir);
     return ret;
    }
   }
  }

  closedir(dir);
 }

 return NULL;
}

static struct roar_dl_lhandle * _load_from_path(const char * name, int flags, int ra_init,
                                                struct roar_dl_librarypara * para) {
 struct roar_dl_lhandle * ret = NULL;
 char * host = NULL;
 char * hostvendor_buffer = NULL;
 char * hostvendor = NULL;
 char * hostname = NULL;
 char * c, * d;

 if ( para != NULL && para->appname != NULL && para->appname[0] != 0 ) {
  host = roar_mm_strdup(para->appname);

  // if we are out of memory we will likely not pass the rest, so just return in error.
  if ( host == NULL )
   return NULL;

  hostname = host;
  c = strstr(host, "<");
  if ( c != NULL ) {
   while (c[-1] == ' ') c--;
   *c = 0;
   c++;
   while (*c == ' ' || *c == '<') c++;
   if ( *c ) {
    d = strstr(c, ">");
    if ( d != NULL )
     *d = 0;

    d = strstr(c, "/");
    if ( d != NULL ) {
     *d = '-';
     hostvendor = c;
    } else {
     hostvendor_buffer = roar_mm_malloc(roar_mm_strlen(c) + 1 /* tailing \0 */ + 6 /* "unreg-" */);

     // see above
     if ( hostvendor_buffer == NULL ) {
      roar_mm_free(host);
      return NULL;
     }

     strcpy(hostvendor_buffer, "unreg-");
     strcat(hostvendor_buffer, c);
     hostvendor = hostvendor_buffer;
    }
   }
  }
 }

 if ( hostvendor == NULL )
  hostvendor = "universal";

 if ( hostname == NULL )
  hostname = "universal";

 ret = _load_from_path_pvn(name, flags, ra_init, para, ROAR_PREFIX_PLUGINS, hostvendor, hostname);

 if ( host != NULL )
  roar_mm_free(host);
 if ( hostvendor_buffer != NULL )
  roar_mm_free(hostvendor_buffer);
 return ret;
}
#endif

static struct roar_dl_lhandle * _roar_dl_open_pluginpath(const char * filename, int flags,
                                      int ra_init, struct roar_dl_librarypara * para) {
 flags |= ROAR_DL_FLAG_PLUGINPATH;
 flags -= ROAR_DL_FLAG_PLUGINPATH;

#ifdef ROAR_HAVE_H_DIRENT
 // do normal open for everything with a path name.
 if ( strstr(filename, "/") != NULL )
  return roar_dl_open(filename, flags, ra_init, para);

 return _load_from_path(filename, flags, ra_init, para);
#else
 // fall back to system open function.
 return roar_dl_open(filename, flags, ra_init, para);
#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;
#if defined(ROAR_HAVE_LIBDL)
#ifdef RTLD_DEEPBIND
 int libdl_flags = RTLD_DEEPBIND;
#else
 int libdl_flags = 0;
#endif
#endif
 int err;

 switch (flags) {
  case ROAR_DL_FLAG_DEFAULTS: flags = ROAR_DL_FLAG_NONE;       break;
  case ROAR_DL_FLAG_PLUGIN:   flags = ROAR_DL_FLAG_PLUGINPATH; break;
 }

 if ( flags & ROAR_DL_FLAG_PLUGINPATH )
  return _roar_dl_open_pluginpath(filename, flags, ra_init, para);

#if defined(ROAR_HAVE_LIBDL)
 if ( flags & ROAR_DL_FLAG_LAZY ) {
  libdl_flags |= RTLD_LAZY;
 } else {
  libdl_flags |= RTLD_NOW;
 }
#endif

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

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

 roar_err_initstore(&(ret->context.error_state));

 ret->flags = flags;
 ret->refc  = 1;

 if ( flags & ROAR_DL_FLAG_STATIC ) {
  if ( filename == NULL ) {
   ret->libname = NULL;
  } else {
   ret->libname = roar_mm_strdup(filename);
  }
 } else {
#if defined(ROAR_HAVE_LIBDL)
  ret->handle = dlopen(filename, libdl_flags);

  if ( ret->handle == NULL ) {
   ROAR_DBG("roar_dl_open(filename='%s', flags=%i, ra_init=%i, para=%p): Can not load library: %s", filename, flags, ra_init, para, roar_dl_errstr(ret));
   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)
   if ( ret->handle != NULL )
    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_ref    (struct roar_dl_lhandle * lhandle) {
 if ( (void*)lhandle < (void*)128 ) {
  ROAR_DBG("roar_dl_ref(lhandle=%p) = -1 // error=BADFH", lhandle);
  roar_err_set(ROAR_ERROR_BADFH);
  return -1;
 }

 lhandle->refc++;

 ROAR_DBG("roar_dl_ref(lhandle=%p) = 0", lhandle);
 return 0;
}

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

 if ( (void*)lhandle < (void*)128 ) {
  ROAR_DBG("roar_dl_unref(lhandle=%p) = -1 // error=BADFH", lhandle);
  roar_err_set(ROAR_ERROR_BADFH);
  return -1;
 }

 lhandle->refc--;

 if ( lhandle->refc ) {
  ROAR_DBG("roar_dl_unref(lhandle=%p) = 0", lhandle);
  return 0;
 }

 if ( lhandle->lib != NULL && lhandle->lib->unload != NULL ) {
  roar_dl_context_restore(lhandle);
  lhandle->lib->unload(lhandle->para, lhandle->lib);
  roar_dl_context_store(lhandle);
 }

#if defined(ROAR_HAVE_LIBDL)
 if ( lhandle->handle == NULL ) {
  ret = 0;
 } else {
  ret = dlclose(_roardl2ldl(lhandle));
 }
#else
 ret = -1;
#endif

 if ( lhandle->context.global_data != NULL )
  roar_mm_free(lhandle->context.global_data);

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

 if ( lhandle->libname != NULL )
  roar_mm_free(lhandle->libname);

 roar_mm_free(lhandle);

 ROAR_DBG("roar_dl_unref(lhandle=%p) = %i", lhandle, ret);
 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): errno=%s, dlerror()='%s'", lhandle, sym, type, ret, strerror(errno), dlerror());
 ROAR_DBG("roar_dl_getsym(lhandle=%p, sym='%s', type=%i) = %p", lhandle, sym, type, ret);

 return ret;
#else
 ROAR_DBG("roar_dl_getsym(lhandle=%p, sym='%s', type=%i) = NULL // errno=NOSYS", lhandle, sym, type, ret);
 roar_err_set(ROAR_ERROR_NOSYS);
 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;
 struct roar_dl_lhandle     * getsymhandle = lhandle;
 void * global_data_state = NULL;
 int i;

 if ( (void*)lhandle < (void*)128 ) {
  if ( prefix == NULL )
   return -1;
 } else {
  if ( lhandle->ra_inited )
   return 0;

  if ( prefix == NULL )
   prefix = lhandle->libname;

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

  if ( lhandle->flags & ROAR_DL_FLAG_STATIC )
   getsymhandle = ROAR_DL_HANDLE_DEFAULT;
 }


 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(getsymhandle, name, -1)) == NULL ) {
  ROAR_DBG("roar_dl_ra_init(lhandle=%p, prefix='%s') = -1", lhandle, prefix);
  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 ( lib->host_appname != NULL || lib->host_abiversion != NULL ) {
  // check for correct host.
  if ( para == NULL ) {
   roar_err_set(ROAR_ERROR_INVAL);
   return -1;
  }
  if ( roar_dl_para_check_version(para, lib->host_appname, lib->host_abiversion) == -1 )
   return -1;
 }

 if ( (lib->libdep == NULL && lib->libdep_len) || (lib->libdep != NULL && !lib->libdep_len) ) {
  roar_err_set(ROAR_ERROR_BADLIB);
  return -1;
 }

 if ( lib->libdep != NULL && lib->libdep_len ) {
  // dynamic loader infos are currently not supported.
  roar_err_set(ROAR_ERROR_NOTSUP);
  return -1;
 }

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

  if ( lib->global_data_len ) {
   lhandle->context.global_data = roar_mm_malloc(lib->global_data_len);
   if ( lhandle->context.global_data == NULL )
    return -1;

   if ( lib->global_data_init == NULL ) {
    memset(lhandle->context.global_data, 0, lib->global_data_len);
   } else {
    memcpy(lhandle->context.global_data, lib->global_data_init, lib->global_data_len);
   }
  }
 }

 if ( lib->global_data_pointer != NULL ) {
  global_data_state = *(lib->global_data_pointer);
  if ( (void*)lhandle < (void*)128 ) {
   *(lib->global_data_pointer) = lib->global_data_init;
  } else {
   *(lib->global_data_pointer) = lhandle->context.global_data;
  }
 }

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

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

 if ( !((void*)lhandle < (void*)128) )
  lhandle->ra_inited = 1;

 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;
}

int                      roar_dl_context_restore(struct roar_dl_lhandle * lhandle) {
 struct roar_error_state error_state;

 ROAR_DBG("roar_dl_context_restore(lhandle=%p) = ?", lhandle);

 if ( (void*)lhandle < (void*)128 ) {
  ROAR_DBG("roar_dl_context_restore(lhandle=%p) = -1 // errno=NOTSUP", lhandle);
  roar_err_set(ROAR_ERROR_NOTSUP);
  return -1;
 }

 roar_err_store(&error_state);
 roar_err_restore(&(lhandle->context.error_state));
 lhandle->context.error_state = error_state;

 if ( lhandle->lib->global_data_pointer != NULL ) {
  ROAR_DBG("roar_dl_context_restore(lhandle=%p): gptr(%p): %p -> %p", lhandle,
           lhandle->lib->global_data_pointer, *(lhandle->lib->global_data_pointer), lhandle->context.global_data);
  lhandle->context.global_data_state = *(lhandle->lib->global_data_pointer);
  *(lhandle->lib->global_data_pointer) = lhandle->context.global_data;
 }

 if ( lhandle->para->notifycore != NULL )
  lhandle->context.notifycore = roar_notify_core_swap_global(lhandle->para->notifycore);

 ROAR_DBG("roar_dl_context_restore(lhandle=%p) = 0", lhandle);
 return 0;
}

int                      roar_dl_context_store(struct roar_dl_lhandle * lhandle) {
 struct roar_error_state error_state;

 ROAR_DBG("roar_dl_context_store(lhandle=%p) = ?", lhandle);

 if ( (void*)lhandle < (void*)128 ) {
  ROAR_DBG("roar_dl_context_store(lhandle=%p) = -1 // errno=NOTSUP", lhandle);
  roar_err_set(ROAR_ERROR_NOTSUP);
  return -1;
 }

 if ( lhandle->para->notifycore != NULL ) {
  roar_notify_core_unref(roar_notify_core_swap_global(lhandle->context.notifycore));
  roar_notify_core_unref(lhandle->context.notifycore);
  lhandle->context.notifycore = NULL;
 }

 if ( lhandle->lib->global_data_pointer != NULL ) {
  ROAR_DBG("roar_dl_context_store(lhandle=%p): gptr(%p): %p -> %p", lhandle,
           lhandle->lib->global_data_pointer, *(lhandle->lib->global_data_pointer), lhandle->context.global_data_state);
  *(lhandle->lib->global_data_pointer) = lhandle->context.global_data_state;
 }

 roar_err_store(&error_state);
 roar_err_restore(&(lhandle->context.error_state));
 lhandle->context.error_state = error_state;

 ROAR_DBG("roar_dl_context_store(lhandle=%p) = 0", lhandle);
 return 0;
}

int                      roar_dl_appsched_trigger(struct roar_dl_lhandle * lhandle, enum roar_dl_appsched_trigger trigger) {
 int (*func)  (struct roar_dl_librarypara * para) = NULL;
 int ret;

 if ( (void*)lhandle < (void*)128 ) {
  roar_err_set(ROAR_ERROR_NOTSUP);
  return -1;
 }

 if ( lhandle->lib->appsched == NULL ) {
  roar_err_set(ROAR_ERROR_NOENT);
  return -1;
 }

 switch (trigger) {
#define _trig(lname,uname) \
  case ROAR_DL_APPSCHED_ ## uname :             \
    func = lhandle->lib->appsched->lname;       \
   break;
  _trig(init, INIT);
  _trig(free, FREE);
  _trig(update, UPDATE);
  _trig(tick, TICK);
  _trig(wait, WAIT);
// use ifndef here so warnings of unhandled enum values will be shown in DEBUG mode.
#ifndef DEBUG
  default:
    roar_err_set(ROAR_ERROR_BADRQC);
    return -1;
   break;
#endif
 }

 if ( func == NULL ) {
  roar_err_set(ROAR_ERROR_NOENT);
  return -1;
 }

 roar_dl_context_restore(lhandle);
 ret = func(lhandle->para);
 roar_dl_context_store(lhandle);
 return ret;
}

//ll