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 struct link_map;
  49
  50 /* Close an object previously opened by _dl_open.  */
  51 extern void _dl_close (void *map) attribute_hidden;
  52 /* Same as above, but without locking and safety checks for user
  53    provided map arguments.  */
  54 extern void _dl_close_worker (struct link_map *map) attribute_hidden;
  55
  56 /* Look up NAME in shared object HANDLE (which may be RTLD_DEFAULT or
  57    RTLD_NEXT).  WHO is the calling function, for RTLD_NEXT.  Returns
  58    the symbol value, which may be NULL.  */
  59 extern void *_dl_sym (void *handle, const char *name, void *who)
  60     internal_function;
  61
  62 /* Look up version VERSION of symbol NAME in shared object HANDLE
  63    (which may be RTLD_DEFAULT or RTLD_NEXT).  WHO is the calling
  64    function, for RTLD_NEXT.  Returns the symbol value, which may be
  65    NULL.  */
  66 extern void *_dl_vsym (void *handle, const char *name, const char *version,
  67                        void *who)
  68     internal_function;
  69
  70 /* Call OPERATE, catching errors from `dl_signal_error'.  If there is no
  71    error, *ERRSTRING is set to null.  If there is an error, *ERRSTRING is
  72    set to a string constructed from the strings passed to _dl_signal_error,
  73    and the error code passed is the return value and *OBJNAME is set to
  74    the object name which experienced the problems.  ERRSTRING if nonzero
  75    points to a malloc'ed string which the caller has to free after use.
  76    ARGS is passed as argument to OPERATE.  MALLOCEDP is set to true only
  77    if the returned string is allocated using the libc's malloc.  */
  78 extern int _dl_catch_error (const char **objname, const char **errstring,
  79                             bool *mallocedp, void (*operate) (void *),
  80                             void *args)
  81      internal_function;
  82
  83 /* Helper function for <dlfcn.h> functions.  Runs the OPERATE function via
  84    _dl_catch_error.  Returns zero for success, nonzero for failure; and
  85    arranges for `dlerror' to return the error details.
  86    ARGS is passed as argument to OPERATE.  */
  87 extern int _dlerror_run (void (*operate) (void *), void *args)
  88      internal_function;
  89
  90 #ifdef SHARED
  91 # define DL_CALLER_DECL /* Nothing */
  92 # define DL_CALLER RETURN_ADDRESS (0)
  93 #else
  94 # define DL_CALLER_DECL , void *dl_caller
  95 # define DL_CALLER dl_caller
  96 #endif
  97
  98 struct dlfcn_hook
  99 {
 100   void *(*dlopen) (const char *file, int mode, void *dl_caller);
 101   int (*dlclose) (void *handle);
 102   void *(*dlsym) (void *handle, const char *name, void *dl_caller);
 103   void *(*dlvsym) (void *handle, const char *name, const char *version,
 104                    void *dl_caller);
 105   char *(*dlerror) (void);
 106   int (*dladdr) (const void *address, Dl_info *info);
 107   int (*dladdr1) (const void *address, Dl_info *info,
 108                   void **extra_info, int flags);
 109   int (*dlinfo) (void *handle, int request, void *arg, void *dl_caller);
 110   void *(*dlmopen) (Lmid_t nsid, const char *file, int mode, void *dl_caller);
 111   void *pad[4];
 112 };
 113
 114 extern struct dlfcn_hook *_dlfcn_hook;
 115 libdl_hidden_proto (_dlfcn_hook)
 116
 117 extern void *__dlopen (const char *file, int mode DL_CALLER_DECL)
 118      attribute_hidden;
 119 extern void *__dlmopen (Lmid_t nsid, const char *file, int mode DL_CALLER_DECL)
 120      attribute_hidden;
 121 extern int __dlclose (void *handle)
 122      attribute_hidden;
 123 extern void *__dlsym (void *handle, const char *name DL_CALLER_DECL)
 124      attribute_hidden;
 125 extern void *__dlvsym (void *handle, const char *name, const char *version
 126                        DL_CALLER_DECL)
 127      attribute_hidden;
 128 extern char *__dlerror (void)
 129      attribute_hidden;
 130 extern int __dladdr (const void *address, Dl_info *info)
 131      attribute_hidden;
 132 extern int __dladdr1 (const void *address, Dl_info *info,
 133                       void **extra_info, int flags)
 134      attribute_hidden;
 135 extern int __dlinfo (void *handle, int request, void *arg DL_CALLER_DECL)
 136      attribute_hidden;
 137
 138 #ifndef SHARED
 139 struct link_map;
 140 extern void * __libc_dlsym_private (struct link_map *map, const char *name)
 141      attribute_hidden;
 142 extern void __libc_register_dl_open_hook (struct link_map *map)
 143      attribute_hidden;
 144 extern void __libc_register_dlfcn_hook (struct link_map *map)
 145      attribute_hidden;
 146 #endif
 147
 148 #endif