ltdl.c

Small Device C Compiler 面向Inter8051

    {
      /* Append a `.' to stop Windows from adding an
	 implicit `.dll' extension. */
      searchname = LT_EMALLOC (char, 2+ LT_STRLEN (filename));
      if (searchname)
	sprintf (searchname, "%s.", filename);
    }
  if (!searchname)
    return 0;

#if __CYGWIN__
  {
    char wpath[MAX_PATH];
    cygwin_conv_to_full_win32_path(searchname, wpath);
    module = LoadLibrary(wpath);
  }
#else
  module = LoadLibrary (searchname);
#endif
  LT_DLFREE (searchname);

  /* libltdl expects this function to fail if it is unable
     to physically load the library.  Sadly, LoadLibrary
     will search the loaded libraries for a match and return
     one of them if the path search load fails.

     We check whether LoadLibrary is returning a handle to
     an already loaded module, and simulate failure if we
     find one. */
  LT_DLMUTEX_LOCK ();
  cur = handles;
  while (cur)
    {
      if (!cur->module)
	{
	  cur = 0;
	  break;
	}

      if (cur->module == module)
	{
	  break;
	}

      cur = cur->next;
  }
  LT_DLMUTEX_UNLOCK ();

  if (cur || !module)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_OPEN));
      module = 0;
    }

  return module;
}

static int
sys_wll_close (loader_data, module)
     lt_user_data loader_data;
     lt_module module;
{
  int	      errors   = 0;

  if (FreeLibrary(module) == 0)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_CLOSE));
      ++errors;
    }

  return errors;
}

static lt_ptr
sys_wll_sym (loader_data, module, symbol)
     lt_user_data loader_data;
     lt_module module;
     const char *symbol;
{
  lt_ptr      address  = GetProcAddress (module, symbol);

  if (!address)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (SYMBOL_NOT_FOUND));
    }

  return address;
}

static struct lt_user_dlloader sys_wll = {
  0, sys_wll_open, sys_wll_close, sys_wll_sym, 0, 0
};

#endif /* __WINDOWS__ */




/* --- LOAD_ADD_ON() INTERFACE LOADER --- */


#ifdef __BEOS__

/* dynamic linking for BeOS */

#include <kernel/image.h>

static lt_module
sys_bedl_open (loader_data, filename)
     lt_user_data loader_data;
     const char *filename;
{
  image_id image = 0;

  if (filename)
    {
      image = load_add_on (filename);
    }
  else
    {
      image_info info;
      int32 cookie = 0;
      if (get_next_image_info (0, &cookie, &info) == B_OK)
	image = load_add_on (info.name);
    }

  if (image <= 0)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_OPEN));
      image = 0;
    }

  return (lt_module) image;
}

static int
sys_bedl_close (loader_data, module)
     lt_user_data loader_data;
     lt_module module;
{
  int errors = 0;

  if (unload_add_on ((image_id) module) != B_OK)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_CLOSE));
      ++errors;
    }

  return errors;
}

static lt_ptr
sys_bedl_sym (loader_data, module, symbol)
     lt_user_data loader_data;
     lt_module module;
     const char *symbol;
{
  lt_ptr address = 0;
  image_id image = (image_id) module;

  if (get_image_symbol (image, symbol, B_SYMBOL_TYPE_ANY, address) != B_OK)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (SYMBOL_NOT_FOUND));
      address = 0;
    }

  return address;
}

static struct lt_user_dlloader sys_bedl = {
  0, sys_bedl_open, sys_bedl_close, sys_bedl_sym, 0, 0
};

#endif /* __BEOS__ */




/* --- DLD_LINK() INTERFACE LOADER --- */


#if HAVE_DLD

/* dynamic linking with dld */

#if HAVE_DLD_H
#include <dld.h>
#endif

static lt_module
sys_dld_open (loader_data, filename)
     lt_user_data loader_data;
     const char *filename;
{
  lt_module module = strdup (filename);

  if (dld_link (filename) != 0)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_OPEN));
      LT_DLFREE (module);
      module = 0;
    }

  return module;
}

static int
sys_dld_close (loader_data, module)
     lt_user_data loader_data;
     lt_module module;
{
  int errors = 0;

  if (dld_unlink_by_file ((char*)(module), 1) != 0)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (CANNOT_CLOSE));
      ++errors;
    }
  else
    {
      LT_DLFREE (module);
    }

  return errors;
}

static lt_ptr
sys_dld_sym (loader_data, module, symbol)
     lt_user_data loader_data;
     lt_module module;
     const char *symbol;
{
  lt_ptr address = dld_get_func (symbol);

  if (!address)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (SYMBOL_NOT_FOUND));
    }

  return address;
}

static struct lt_user_dlloader sys_dld = {
  0, sys_dld_open, sys_dld_close, sys_dld_sym, 0, 0
};

#endif /* HAVE_DLD */




/* --- DLPREOPEN() INTERFACE LOADER --- */


/* emulate dynamic linking using preloaded_symbols */

typedef struct lt_dlsymlists_t
{
  struct lt_dlsymlists_t       *next;
  const lt_dlsymlist	       *syms;
} lt_dlsymlists_t;

static	const lt_dlsymlist     *default_preloaded_symbols	= 0;
static	lt_dlsymlists_t	       *preloaded_symbols		= 0;

static int
presym_init (loader_data)
     lt_user_data loader_data;
{
  int errors = 0;

  LT_DLMUTEX_LOCK ();

  preloaded_symbols = 0;
  if (default_preloaded_symbols)
    {
      errors = lt_dlpreload (default_preloaded_symbols);
    }

  LT_DLMUTEX_UNLOCK ();

  return errors;
}

static int
presym_free_symlists ()
{
  lt_dlsymlists_t *lists;

  LT_DLMUTEX_LOCK ();

  lists = preloaded_symbols;
  while (lists)
    {
      lt_dlsymlists_t	*tmp = lists;

      lists = lists->next;
      LT_DLFREE (tmp);
    }
  preloaded_symbols = 0;

  LT_DLMUTEX_UNLOCK ();

  return 0;
}

static int
presym_exit (loader_data)
     lt_user_data loader_data;
{
  presym_free_symlists ();
  return 0;
}

static int
presym_add_symlist (preloaded)
     const lt_dlsymlist *preloaded;
{
  lt_dlsymlists_t *tmp;
  lt_dlsymlists_t *lists;
  int		   errors   = 0;

  LT_DLMUTEX_LOCK ();

  lists = preloaded_symbols;
  while (lists)
    {
      if (lists->syms == preloaded)
	{
	  goto done;
	}
      lists = lists->next;
    }

  tmp = LT_EMALLOC (lt_dlsymlists_t, 1);
  if (tmp)
    {
      memset (tmp, 0, sizeof(lt_dlsymlists_t));
      tmp->syms = preloaded;
      tmp->next = preloaded_symbols;
      preloaded_symbols = tmp;
    }
  else
    {
      ++errors;
    }

 done:
  LT_DLMUTEX_UNLOCK ();
  return errors;
}

static lt_module
presym_open (loader_data, filename)
     lt_user_data loader_data;
     const char *filename;
{
  lt_dlsymlists_t *lists;
  lt_module	   module = (lt_module) 0;

  LT_DLMUTEX_LOCK ();
  lists = preloaded_symbols;

  if (!lists)
    {
      LT_DLMUTEX_SETERROR (LT_DLSTRERROR (NO_SYMBOLS));
      goto done;
    }

  /* Can't use NULL as the reflective symbol header, as NULL is
     used to mark the end of the entire symbol list.  Self-dlpreopened
     symbols follow this magic number, chosen to be an unlikely
     clash with a real module name.  */
  if (!filename)
    {
      filename = "@PROGRAM@";
    }

  while (lists)
    {
      const lt_dlsymlist *syms = lists->syms;

      while (syms->name)
	{
	  if (!syms->address && strcmp(syms->name, filename) == 0)
	    {
	      module = (lt_module) syms;
	      goto done;
	    }
	  ++syms;
	}

      lists = lists->next;
    }

  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (FILE_NOT_FOUND));

 done:
  LT_DLMUTEX_UNLOCK ();
  return module;
}

static int
presym_close (loader_data, module)
     lt_user_data loader_data;
     lt_module module;
{
  /* Just to silence gcc -Wall */
  module = 0;
  return 0;
}

static lt_ptr
presym_sym (loader_data, module, symbol)
     lt_user_data loader_data;
     lt_module module;
     const char *symbol;
{
  lt_dlsymlist *syms = (lt_dlsymlist*) module;

  ++syms;
  while (syms->address)
    {
      if (strcmp(syms->name, symbol) == 0)
	{
	  return syms->address;
	}

    ++syms;
  }

  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (SYMBOL_NOT_FOUND));

  return 0;
}

static struct lt_user_dlloader presym = {
  0, presym_open, presym_close, presym_sym, presym_exit, 0
};





/* --- DYNAMIC MODULE LOADING --- */


/* The type of a function used at each iteration of  foreach_dirinpath().  */
typedef int	foreach_callback_func LT_PARAMS((char *filename, lt_ptr data1,
						 lt_ptr data2));

static	int	foreach_dirinpath     LT_PARAMS((const char *search_path,
						 const char *base_name,
						 foreach_callback_func *func,
						 lt_ptr data1, lt_ptr data2));

static	int	find_file_callback    LT_PARAMS((char *filename, lt_ptr data,
						 lt_ptr ignored));
static	int	find_handle_callback  LT_PARAMS((char *filename, lt_ptr data,
						 lt_ptr ignored));
static	int	foreachfile_callback  LT_PARAMS((char *filename, lt_ptr data1,
						 lt_ptr data2));


static	int     canonicalize_path     LT_PARAMS((const char *path,
						 char **pcanonical));
static	int	argzize_path 	      LT_PARAMS((const char *path,
						 char **pargz,
						 size_t *pargz_len));
static	FILE   *find_file	      LT_PARAMS((const char *search_path,
						 const char *base_name,
						 char **pdir));
static	lt_dlhandle *find_handle      LT_PARAMS((const char *search_path,
						 const char *base_name,
						 lt_dlhandle *handle));
static	int	find_module	      LT_PARAMS((lt_dlhandle *handle,
						 const char *dir,
						 const char *libdir,
						 const char *dlname,
						 const char *old_name,
						 int installed));
static	int	free_vars	      LT_PARAMS((char *dlname, char *oldname,
						 char *libdir, char *deplibs));
static	int	load_deplibs	      LT_PARAMS((lt_dlhandle handle,
						 char *deplibs));
static	int	trim		      LT_PARAMS((char **dest,
						 const char *str));
static	int	try_dlopen	      LT_PARAMS((lt_dlhandle *handle,
						 const char *filename));
static	int	tryall_dlopen	      LT_PARAMS((lt_dlhandle *handle,
						 const char *filename));
static	int	unload_deplibs	      LT_PARAMS((lt_dlhandle handle));
static	int	lt_argz_insert	      LT_PARAMS((char **pargz,
						 size_t *pargz_len,
						 char *before,
						 const char *entry));
static	int	lt_argz_insertinorder LT_PARAMS((char **pargz,
						 size_t *pargz_len,
						 const char *entry));
static	int	lt_argz_insertdir     LT_PARAMS((char **pargz,
						 size_t *pargz_len,
						 const char *dirnam,
						 struct dirent *dp));
static	int	lt_dlpath_insertdir   LT_PARAMS((char **ppath,
						 char *before,
						 const char *dir));
static	int	list_files_by_dir     LT_PARAMS((const char *dirnam,
						 char **pargz,
						 size_t *pargz_len));
static	int	file_not_found	      LT_PARAMS((void));

static	char	       *user_search_path= 0;
static	lt_dlloader    *loaders		= 0;
static	lt_dlhandle	handles 	= 0;
static	int		initialized 	= 0;

/* Initialize libltdl. */
int
lt_dlinit ()
{
  int	      errors   = 0;

  LT_DLMUTEX_LOCK ();

  /* Initialize only at first call. */
  if (++initialized == 1)
    {
      handles = 0;
      user_search_path = 0; /* empty search path */

#if HAVE_LIBDL && !defined(__CYGWIN__)
      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_dl, "dlopen");
#endif
#if HAVE_SHL_LOAD
      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_shl, "dlopen");
#endif
#ifdef __WINDOWS__
      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_wll, "dlopen");
#endif
#ifdef __BEOS__
      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_bedl, "dlopen");
#endif
#if HAVE_DLD
      errors += lt_dlloader_add (lt_dlloader_next (0), &sys_dld, "dld");
#endif
      errors += lt_dlloader_add (lt_dlloader_next (0), &presym, "dlpreload");

      if (presym_init (presym.dlloader_data))
	{
	  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (INIT_LOADER));
	  ++errors;
	}
      else if (errors != 0)
	{
	  LT_DLMUTEX_SETERROR (LT_DLSTRERROR (DLOPEN_NOT_SUPPORTED));
	  ++errors;
	}
    }

  LT_DLMUTEX_UNLOCK ();

  return errors;
}

int
lt_dlpreload (preloaded)
     const lt_dlsymlist *preloaded;
{
  int errors = 0;

  if (preloaded)
    {
      errors = presym_add_symlist (preloaded);
    }
  else
    {
      presym_free_symlists();

      LT_DLMUTEX_LOCK ();
      if (default_preloaded_symbols)
	{
	  errors = lt_dlpreload (default_preloaded_symbols);
	}
      LT_DLMUTEX_UNLOCK ();
    }

  return errors;
}

int
lt_dlpreload_default (preloaded)
     const lt_dlsymlist *preloaded;
{
  LT_DLMUTEX_LOCK ();
  default_preloaded_symbols = preloaded;
  LT_DLMUTEX_UNLOCK ();
  return 0;
}

int
lt_dlexit ()
{
  /* shut down libltdl */