include/dlfcn.h

   1 #ifndef _DLFCN_H
   2 #include <dlfcn/dlfcn.h>
   3 #ifndef _ISOMAC
   4 #include <link.h>               /* For ElfW.  */
   5 #include <stdbool.h>
   6
   7 /* Internally used flag.  */
   8 #define __RTLD_DLOPEN   0x80000000
   9 #define __RTLD_SPROF    0x40000000
  10 #define __RTLD_OPENEXEC 0x20000000
  11 #define __RTLD_CALLMAP  0x10000000
  12 #define __RTLD_AUDIT    0x08000000
  13 #define __RTLD_SECURE   0x04000000 /* Apply additional security checks.  */
  14 #define __RTLD_NOIFUNC  0x02000000 /* Suppress calling ifunc functions.  */
  15
  16 #define __LM_ID_CALLER  -2
  17
  18 #ifdef SHARED
  19 /* Locally stored program arguments.  */
  20 extern int __dlfcn_argc attribute_hidden;
  21 extern char **__dlfcn_argv attribute_hidden;
  22 #else
  23 /* These variables are defined and initialized in the startup code.  */
  24 extern int __libc_argc attribute_hidden;
  25 extern char **__libc_argv attribute_hidden;
  26
  27 # define __dlfcn_argc __libc_argc
  28 # define __dlfcn_argv __libc_argv
  29 #endif
  30
  31
  32 /* Now define the internal interfaces.  */
  33
  34 #define __libc_dlopen(name) \
  35   __libc_dlopen_mode (name, RTLD_LAZY | __RTLD_DLOPEN)
  36 extern void *__libc_dlopen_mode  (const char *__name, int __mode);
  37 extern void *__libc_dlsym   (void *__map, const char *__name);
  38 extern int   __libc_dlclose (void *__map);
  39 libc_hidden_proto (__libc_dlopen_mode)
  40 libc_hidden_proto (__libc_dlsym)
  41 libc_hidden_proto (__libc_dlclose)
  42
  43 /* Locate shared object containing the given address.  */
  44 #ifdef ElfW
  45 extern int _dl_addr (const void *address, Dl_info *info,
  46                      struct link_map **mapp, const ElfW(Sym) **symbolp)
  47      internal_function;
  48 libc_hidden_proto (_dl_addr)
  49 #endif
  50
  51 struct link_map;
  52
  53 /* Close an object previously opened by _dl_open.  */
  54 extern void _dl_close (void *map) attribute_hidden;
  55 /* Same as above, but without locking and safety checks for user
  56    provided map arguments.  */
  57 extern void _dl_close_worker (struct link_map *map, bool force)
  58     attribute_hidden;
  59
  60 /* Look up NAME in shared object HANDLE (which may be RTLD_DEFAULT or
  61    RTLD_NEXT).  WHO is the calling function, for RTLD_NEXT.  Returns
  62    the symbol value, which may be NULL.  */
  63 extern void *_dl_sym (void *handle, const char *name, void *who)
  64     internal_function;
  65
  66 /* Look up version VERSION of symbol NAME in shared object HANDLE
  67    (which may be RTLD_DEFAULT or RTLD_NEXT).  WHO is the calling
  68    function, for RTLD_NEXT.  Returns the symbol value, which may be
  69    NULL.  */
  70 extern void *_dl_vsym (void *handle, const char *name, const char *version,
  71                        void *who)
  72     internal_function;
  73
  74 /* Call OPERATE, catching errors from `dl_signal_error'.  If there is no
  75    error, *ERRSTRING is set to null.  If there is an error, *ERRSTRING is
  76    set to a string constructed from the strings passed to _dl_signal_error,
  77    and the error code passed is the return value and *OBJNAME is set to
  78    the object name which experienced the problems.  ERRSTRING if nonzero
  79    points to a malloc'ed string which the caller has to free after use.
  80    ARGS is passed as argument to OPERATE.  MALLOCEDP is set to true only
  81    if the returned string is allocated using the libc's malloc.  */
  82 extern int _dl_catch_error (const char **objname, const char **errstring,
  83                             bool *mallocedp, void (*operate) (void *),
  84                             void *args)
  85      internal_function;
  86
  87 /* Helper function for <dlfcn.h> functions.  Runs the OPERATE function via
  88    _dl_catch_error.  Returns zero for success, nonzero for failure; and
  89    arranges for `dlerror' to return the error details.
  90    ARGS is passed as argument to OPERATE.  */
  91 extern int _dlerror_run (void (*operate) (void *), void *args)
  92      internal_function;
  93
  94 #ifdef SHARED
  95 # define DL_CALLER_DECL /* Nothing */
  96 # define DL_CALLER RETURN_ADDRESS (0)
  97 #else
  98 # define DL_CALLER_DECL , void *dl_caller
  99 # define DL_CALLER dl_caller
 100 #endif
 101
 102 struct dlfcn_hook
 103 {
 104   void *(*dlopen) (const char *file, int mode, void *dl_caller);
 105   int (*dlclose) (void *handle);
 106   void *(*dlsym) (void *handle, const char *name, void *dl_caller);
 107   void *(*dlvsym) (void *handle, const char *name, const char *version,
 108                    void *dl_caller);
 109   char *(*dlerror) (void);
 110   int (*dladdr) (const void *address, Dl_info *info);
 111   int (*dladdr1) (const void *address, Dl_info *info,
 112                   void **extra_info, int flags);
 113   int (*dlinfo) (void *handle, int request, void *arg, void *dl_caller);
 114   void *(*dlmopen) (Lmid_t nsid, const char *file, int mode, void *dl_caller);
 115   void *pad[4];
 116 };
 117
 118 extern struct dlfcn_hook *_dlfcn_hook;
 119 libdl_hidden_proto (_dlfcn_hook)
 120
 121 extern void *__dlopen (const char *file, int mode DL_CALLER_DECL)
 122      attribute_hidden;
 123 extern void *__dlmopen (Lmid_t nsid, const char *file, int mode DL_CALLER_DECL)
 124      attribute_hidden;
 125 extern int __dlclose (void *handle)
 126      attribute_hidden;
 127 extern void *__dlsym (void *handle, const char *name DL_CALLER_DECL)
 128      attribute_hidden;
 129 extern void *__dlvsym (void *handle, const char *name, const char *version
 130                        DL_CALLER_DECL)
 131      attribute_hidden;
 132 extern char *__dlerror (void)
 133      attribute_hidden;
 134 extern int __dladdr (const void *address, Dl_info *info)
 135      attribute_hidden;
 136 extern int __dladdr1 (const void *address, Dl_info *info,
 137                       void **extra_info, int flags)
 138      attribute_hidden;
 139 extern int __dlinfo (void *handle, int request, void *arg DL_CALLER_DECL)
 140      attribute_hidden;
 141
 142 #ifndef SHARED
 143 struct link_map;
 144 extern void * __libc_dlsym_private (struct link_map *map, const char *name)
 145      attribute_hidden;
 146 extern void __libc_register_dl_open_hook (struct link_map *map)
 147      attribute_hidden;
 148 extern void __libc_register_dlfcn_hook (struct link_map *map)
 149      attribute_hidden;
 150 #endif
 151 #endif
 152
 153 #endif