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