include/dlfcn.h

   1 #ifndef _DLFCN_H
   2 #include <dlfcn/dlfcn.h>
   3 #include <link.h>               /* For ElfW.  */
   4 #include <stdbool.h>
   5
   6 /* Internally used flag.  */
   7 #define __RTLD_DLOPEN   0x80000000
   8 #define __RTLD_SPROF    0x40000000
   9 #define __RTLD_OPENEXEC 0x20000000
  10 #define __RTLD_CALLMAP  0x10000000
  11 #define __RTLD_AUDIT    0x08000000
  12
  13 #define __LM_ID_CALLER  -2
  14
  15 #ifdef SHARED
  16 /* Locally stored program arguments.  */
  17 extern int __dlfcn_argc attribute_hidden;
  18 extern char **__dlfcn_argv attribute_hidden;
  19 #else
  20 /* These variables are defined and initialized in the startup code.  */
  21 extern int __libc_argc attribute_hidden;
  22 extern char **__libc_argv attribute_hidden;
  23
  24 # define __dlfcn_argc __libc_argc
  25 # define __dlfcn_argv __libc_argv
  26 #endif
  27
  28
  29 /* Now define the internal interfaces.  */
  30
  31 #define __libc_dlopen(name) \
  32   __libc_dlopen_mode (name, RTLD_LAZY | __RTLD_DLOPEN)
  33 extern void *__libc_dlopen_mode  (__const char *__name, int __mode);
  34 extern void *__libc_dlsym   (void *__map, __const char *__name);
  35 extern int   __libc_dlclose (void *__map);
  36 libc_hidden_proto (__libc_dlopen_mode)
  37 libc_hidden_proto (__libc_dlsym)
  38 libc_hidden_proto (__libc_dlclose)
  39
  40 /* Locate shared object containing the given address.  */
  41 #ifdef ElfW
  42 extern int _dl_addr (const void *address, Dl_info *info,
  43                      struct link_map **mapp, const ElfW(Sym) **symbolp)
  44      internal_function;
  45 libc_hidden_proto (_dl_addr)
  46 #endif
  47
  48 /* Close an object previously opened by _dl_open.  */
  49 extern void _dl_close (void *map) attribute_hidden;
  50
  51 /* Look up NAME in shared object HANDLE (which may be RTLD_DEFAULT or
  52    RTLD_NEXT).  WHO is the calling function, for RTLD_NEXT.  Returns
  53    the symbol value, which may be NULL.  */
  54 extern void *_dl_sym (void *handle, const char *name, void *who)
  55     internal_function;
  56
  57 /* Look up version VERSION of symbol NAME in shared object HANDLE
  58    (which may be RTLD_DEFAULT or RTLD_NEXT).  WHO is the calling
  59    function, for RTLD_NEXT.  Returns the symbol value, which may be
  60    NULL.  */
  61 extern void *_dl_vsym (void *handle, const char *name, const char *version,
  62                        void *who)
  63     internal_function;
  64
  65 /* Call OPERATE, catching errors from `dl_signal_error'.  If there is no
  66    error, *ERRSTRING is set to null.  If there is an error, *ERRSTRING is
  67    set to a string constructed from the strings passed to _dl_signal_error,
  68    and the error code passed is the return value and *OBJNAME is set to
  69    the object name which experienced the problems.  ERRSTRING if nonzero
  70    points to a malloc'ed string which the caller has to free after use.
  71    ARGS is passed as argument to OPERATE.  MALLOCEDP is set to true only
  72    if the returned string is allocated using the libc's malloc.  */
  73 extern int _dl_catch_error (const char **objname, const char **errstring,
  74                             bool *mallocedp, void (*operate) (void *),
  75                             void *args)
  76      internal_function;
  77
  78 /* Helper function for <dlfcn.h> functions.  Runs the OPERATE function via
  79    _dl_catch_error.  Returns zero for success, nonzero for failure; and
  80    arranges for `dlerror' to return the error details.
  81    ARGS is passed as argument to OPERATE.  */
  82 extern int _dlerror_run (void (*operate) (void *), void *args)
  83      internal_function;
  84
  85 #ifdef SHARED
  86 # define DL_CALLER_DECL /* Nothing */
  87 # define DL_CALLER RETURN_ADDRESS (0)
  88 #else
  89 # define DL_CALLER_DECL , void *dl_caller
  90 # define DL_CALLER dl_caller
  91 #endif
  92
  93 struct dlfcn_hook
  94 {
  95   void *(*dlopen) (const char *file, int mode, void *dl_caller);
  96   int (*dlclose) (void *handle);
  97   void *(*dlsym) (void *handle, const char *name, void *dl_caller);
  98   void *(*dlvsym) (void *handle, const char *name, const char *version,
  99                    void *dl_caller);
 100   char *(*dlerror) (void);
 101   int (*dladdr) (const void *address, Dl_info *info);
 102   int (*dladdr1) (const void *address, Dl_info *info,
 103                   void **extra_info, int flags);
 104   int (*dlinfo) (void *handle, int request, void *arg, void *dl_caller);
 105   void *(*dlmopen) (Lmid_t nsid, const char *file, int mode, void *dl_caller);
 106   void *pad[4];
 107 };
 108
 109 extern struct dlfcn_hook *_dlfcn_hook;
 110 libdl_hidden_proto (_dlfcn_hook)
 111
 112 extern void *__dlopen (const char *file, int mode DL_CALLER_DECL)
 113      attribute_hidden;
 114 extern void *__dlmopen (Lmid_t nsid, const char *file, int mode DL_CALLER_DECL)
 115      attribute_hidden;
 116 extern int __dlclose (void *handle)
 117      attribute_hidden;
 118 extern void *__dlsym (void *handle, const char *name DL_CALLER_DECL)
 119      attribute_hidden;
 120 extern void *__dlvsym (void *handle, const char *name, const char *version
 121                        DL_CALLER_DECL)
 122      attribute_hidden;
 123 extern char *__dlerror (void)
 124      attribute_hidden;
 125 extern int __dladdr (const void *address, Dl_info *info)
 126      attribute_hidden;
 127 extern int __dladdr1 (const void *address, Dl_info *info,
 128                       void **extra_info, int flags)
 129      attribute_hidden;
 130 extern int __dlinfo (void *handle, int request, void *arg DL_CALLER_DECL)
 131      attribute_hidden;
 132
 133 #ifndef SHARED
 134 struct link_map;
 135 extern void * __libc_dlsym_private (struct link_map *map, const char *name)
 136      attribute_hidden;
 137 extern void __libc_register_dl_open_hook (struct link_map *map)
 138      attribute_hidden;
 139 extern void __libc_register_dlfcn_hook (struct link_map *map)
 140      attribute_hidden;
 141 #endif
 142
 143 #endif