src/dlmodule.c

   1 /*
   2  * Grace - GRaphing, Advanced Computation and Exploration of data
   3  *
   4  * Home page: http://plasma-gate.weizmann.ac.il/Grace/
   5  *
   6  * Copyright (c) 1991-95 Paul J Turner, Portland, OR
   7  * Copyright (c) 1996-99 Grace Development Team
   8  *
   9  * Maintained by Evgeny Stambulchik
  10  *
  11  *
  12  *                           All Rights Reserved
  13  *
  14  *    This program is free software; you can redistribute it and/or modify
  15  *    it under the terms of the GNU General Public License as published by
  16  *    the Free Software Foundation; either version 2 of the License, or
  17  *    (at your option) any later version.
  18  *
  19  *    This program is distributed in the hope that it will be useful,
  20  *    but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  *    GNU General Public License for more details.
  23  *
  24  *    You should have received a copy of the GNU General Public License
  25  *    along with this program; if not, write to the Free Software
  26  *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  27  */
  28
  29 /*
  30  * dlmodule.c - DLL stuff for Grace
  31  * The following interfaces are supported:
  32  *  + dlopen() (Linux, SunOS, Solaris, OSF, IRIX, AIX-4, UnixWare, ...)
  33  *  + shl_load() (HP/UX)
  34  *  + AIX-3 - there is a free dlopen() emulation library
  35  *  - VMS ??
  36  */
  37
  38 #include <config.h>
  39
  40 #if defined(HAVE_DLOPEN)
  41 #  include <dlfcn.h>
  42 #endif
  43
  44 #if defined(HAVE_SHL_LOAD)
  45 #  include <dl.h>
  46 #endif
  47
  48 #include <string.h>
  49
  50 #include "dlmodule.h"
  51
  52 #include "defines.h"
  53 #include "utils.h"
  54
  55 int dl_load_fast = TRUE; /* controls type of DL module load */
  56 /* TODO: make it tunable through a command */
  57
  58 int load_module(char *fname, char *dl_function, char *dl_key, int dl_type)
  59 {
  60 #if defined(HAVE_DL)
  61
  62     int dlflag;
  63     void *handle;
  64     char *error;
  65     symtab_entry newkey;
  66     int retval;
  67
  68     if ((dl_type < 0) || (dl_key == NULL) || (dl_function == NULL)) {
  69         errmsg("Improper call to load_module()");
  70         return RETURN_FAILURE;
  71     }
  72
  73 #if defined(HAVE_DLOPEN)
  74 #  if defined(HAVE_RTLD_NOW)
  75     if (dl_load_fast == TRUE) {
  76         dlflag = RTLD_LAZY;
  77     } else {
  78         dlflag = RTLD_NOW;
  79     }
  80 #  else
  81     dlflag = 1;
  82 #  endif
  83
  84     handle = (void *) dlopen (fname, dlflag);
  85     if (!handle) {
  86         errmsg ((char *) dlerror());
  87         return RETURN_FAILURE;
  88     }
  89
  90     newkey.data = dlsym(handle, dl_function);
  91     if ((error = (char *) dlerror()) != NULL) {
  92         errmsg(error);
  93         dlclose(handle);
  94         return RETURN_FAILURE;
  95     }
  96
  97 #endif /* end dlopen interface */
  98
  99 #if defined(HAVE_SHL_LOAD)
 100
 101     if (dl_load_fast == TRUE) {
 102         dlflag = BIND_DEFERRED;
 103     } else {
 104         dlflag = BIND_IMMEDIATE;
 105     }
 106
 107     handle = (void *) shl_load (fname, dlflag, 0L);
 108     if (!handle) {
 109 #if defined(HAVE_STRERROR)
 110         errmsg(strerror(errno));
 111 #else
 112 # if defined(HAVE_SYS_ERRLIST_DECL)
 113         errmsg(sys_errlist[errno]);
 114 # else
 115         errmsg("DL module initialization failed");
 116 # endif
 117 #endif
 118         return RETURN_FAILURE;
 119     }
 120
 121     if (shl_findsym(handle, dl_function, TYPE_UNDEFINED, &newkey.data) != NULL) {
 122 #if defined(HAVE_STRERROR)
 123         errmsg(strerror(errno));
 124 #else
 125 # if defined(HAVE_SYS_ERRLIST_DECL)
 126         errmsg(sys_errlist[errno]);
 127 # else
 128         errmsg("Error while resolving symbol");
 129 # endif
 130 #endif
 131         shl_unload(handle);
 132         return RETURN_FAILURE;
 133     }
 134
 135 #endif /* end shl_load interface */
 136
 137     newkey.type = dl_type;
 138     newkey.s = copy_string(NULL, dl_key);
 139
 140     retval = addto_symtab(newkey);
 141     xfree(newkey.s);
 142     return retval;
 143
 144 #else /* no support for DL */
 145     errmsg("No support for DL modules on your OS");
 146     return RETURN_FAILURE;
 147 #endif
 148 }