src/switch_dso.c

   1 /*
   2  * Cross Platform dso/dll load abstraction
   3  * Copyright(C) 2008 Michael Jerris
   4  *
   5  * You may opt to use, copy, modify, merge, publish, distribute and/or sell
   6  * copies of the Software, and permit persons to whom the Software is
   7  * furnished to do so.
   8  *
   9  * This work is provided under this license on an "as is" basis, without warranty of any kind,
  10  * either expressed or implied, including, without limitation, warranties that the covered code
  11  * is free of defects, merchantable, fit for a particular purpose or non-infringing. The entire
  12  * risk as to the quality and performance of the covered code is with you. Should any covered
  13  * code prove defective in any respect, you (not the initial developer or any other contributor)
  14  * assume the cost of any necessary servicing, repair or correction. This disclaimer of warranty
  15  * constitutes an essential part of this license. No use of any covered code is authorized hereunder
  16  * except under this disclaimer.
  17  *
  18  */
  19
  20 #include <switch.h>
  21 #include "switch_dso.h"
  22 #include <stdlib.h>
  23 #include <string.h>
  24
  25 #ifdef WIN32
  26
  27 SWITCH_DECLARE(void) switch_dso_destroy(switch_dso_lib_t *lib)
  28 {
  29         if (lib && *lib) {
  30                 FreeLibrary(*lib);
  31                 *lib = NULL;
  32         }
  33 }
  34
  35 SWITCH_DECLARE(switch_dso_lib_t) switch_dso_open(const char *path, int global, char **err)
  36 {
  37         HINSTANCE lib;
  38
  39         lib = LoadLibraryEx(path, NULL, 0);
  40
  41         if (!lib) {
  42                 lib = LoadLibraryEx(path, NULL, LOAD_WITH_ALTERED_SEARCH_PATH);
  43         }
  44
  45         if (!lib) {
  46                 lib = LoadLibraryEx(path, NULL, LOAD_LIBRARY_SEARCH_DEFAULT_DIRS);
  47         }
  48
  49         if (!lib) {
  50                 DWORD error = GetLastError();
  51                 *err = switch_mprintf("dll open error [%ul]\n", error);
  52         }
  53
  54         return lib;
  55 }
  56
  57 SWITCH_DECLARE(switch_dso_func_t) switch_dso_func_sym(switch_dso_lib_t lib, const char *sym, char **err)
  58 {
  59         FARPROC func = GetProcAddress(lib, sym);
  60         if (!func) {
  61                 DWORD error = GetLastError();
  62                 *err = switch_mprintf("dll sym error [%ul]\n", error);
  63         }
  64         return (switch_dso_func_t) func;
  65 }
  66
  67 SWITCH_DECLARE(void *) switch_dso_data_sym(switch_dso_lib_t lib, const char *sym, char **err)
  68 {
  69         FARPROC addr = GetProcAddress(lib, sym);
  70         if (!addr) {
  71                 DWORD error = GetLastError();
  72                 *err = switch_mprintf("dll sym error [%ul]\n", error);
  73         }
  74         return (void *) (intptr_t) addr;
  75 }
  76
  77
  78 #else
  79 /*
  80 ** {========================================================================
  81 ** This is an implementation of loadlib based on the dlfcn interface.
  82 ** The dlfcn interface is available in Linux, SunOS, Solaris, IRIX, FreeBSD,
  83 ** NetBSD, AIX 4.2, HPUX 11, and  probably most other Unix flavors, at least
  84 ** as an emulation layer on top of native functions.
  85 ** =========================================================================
  86 */
  87
  88
  89 #include <dlfcn.h>
  90
  91 void switch_dso_destroy(switch_dso_lib_t *lib)
  92 {
  93         if (lib && *lib) {
  94 #ifndef HAVE_FAKE_DLCLOSE
  95                 dlclose(*lib);
  96 #endif
  97                 *lib = NULL;
  98         }
  99 }
 100
 101 switch_dso_lib_t switch_dso_open(const char *path, int global, char **err)
 102 {
 103         void *lib;
 104
 105         if (global) {
 106                 lib = dlopen(path, RTLD_NOW | RTLD_GLOBAL);
 107         } else {
 108                 lib = dlopen(path, RTLD_NOW | RTLD_LOCAL);
 109         }
 110
 111         if (lib == NULL) {
 112                 const char *dlerr = dlerror();
 113                 /* Work around broken uclibc returning NULL on both dlopen() and dlerror() */
 114                 if (dlerr) {
 115                         *err = strdup(dlerr);
 116                 } else {
 117                         *err = strdup("Unknown error");
 118                 }
 119         }
 120         return lib;
 121 }
 122
 123 switch_dso_func_t switch_dso_func_sym(switch_dso_lib_t lib, const char *sym, char **err)
 124 {
 125         void *func = dlsym(lib, sym);
 126         if (!func) {
 127                 *err = strdup(dlerror());
 128         }
 129         return (switch_dso_func_t) (intptr_t) func;
 130 }
 131
 132 void *switch_dso_data_sym(switch_dso_lib_t lib, const char *sym, char **err)
 133 {
 134         void *addr = dlsym(lib, sym);
 135         if (!addr) {
 136                 char *err_str = NULL;
 137                 dlerror();
 138
 139                 if (!(addr = dlsym(lib, sym))) {
 140                         err_str = (char *)dlerror();
 141                 }
 142
 143                 if (err_str) {
 144                         *err = strdup(err_str);
 145                 }
 146         }
 147         return addr;
 148 }
 149
 150 #endif
 151 /* }====================================================== */
 152
 153 /* For Emacs:
 154  * Local Variables:
 155  * mode:c
 156  * indent-tabs-mode:t
 157  * tab-width:4
 158  * c-basic-offset:4
 159  * End:
 160  * For VIM:
 161  * vim:set softtabstop=4 shiftwidth=4 tabstop=4 noet
 162  */