/* Provide relocatable packages.   Copyright (C) 2003 Free Software Foundation, Inc.   Written by Bruno Haible <bruno@clisp.org>, 2003.   This program is free software; you can redistribute it and/or modify it   under the terms of the GNU Library General Public License as published   by the Free Software Foundation; either version 2, or (at your option)   any later version.   This program is distributed in the hope that it will be useful,   but WITHOUT ANY WARRANTY; without even the implied warranty of   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU   Library General Public License for more details.   You should have received a copy of the GNU Library General Public   License along with this program; if not, write to the Free Software   Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307,   USA.  *//* Tell glibc's <stdio.h> to provide a prototype for getline().   This must come before <config.h> because <config.h> may include   <features.h>, and once <features.h> has been included, it's too late.  */#ifndef _GNU_SOURCE# define _GNU_SOURCE	1#endif#ifdef HAVE_CONFIG_H# include "config.h"#endif/* Specification.  */#include "relocatable.h"#if ENABLE_RELOCATABLE#include <stddef.h>#include <stdio.h>#include <stdlib.h>#include <string.h>#ifdef NO_XMALLOC# define xmalloc malloc#else# include "xmalloc.h"#endif#if DEPENDS_ON_LIBCHARSET# include <libcharset.h>#endif#if DEPENDS_ON_LIBICONV && HAVE_ICONV# include <iconv.h>#endif#if DEPENDS_ON_LIBINTL && ENABLE_NLS# include <libintl.h>#endif/* Faked cheap 'bool'.  */#undef bool#undef false#undef true#define bool int#define false 0#define true 1/* Pathname support.   ISSLASH(C)           tests whether C is a directory separator character.   IS_PATH_WITH_DIR(P)  tests whether P contains a directory specification. */#if defined _WIN32 || defined __WIN32__ || defined __EMX__ || defined __DJGPP__  /* Win32, OS/2, DOS */# define ISSLASH(C) ((C) == '/' || (C) == '\\')# define HAS_DEVICE(P) \    ((((P)[0] >= 'A' && (P)[0] <= 'Z') || ((P)[0] >= 'a' && (P)[0] <= 'z')) \     && (P)[1] == ':')# define IS_PATH_WITH_DIR(P) \    (strchr (P, '/') != NULL || strchr (P, '\\') != NULL || HAS_DEVICE (P))# define FILESYSTEM_PREFIX_LEN(P) (HAS_DEVICE (P) ? 2 : 0)#else  /* Unix */# define ISSLASH(C) ((C) == '/')# define IS_PATH_WITH_DIR(P) (strchr (P, '/') != NULL)# define FILESYSTEM_PREFIX_LEN(P) 0#endif/* Original installation prefix.  */static char *orig_prefix;static size_t orig_prefix_len;/* Current installation prefix.  */static char *curr_prefix;static size_t curr_prefix_len;/* These prefixes do not end in a slash.  Anything that will be concatenated   to them must start with a slash.  *//* Sets the original and the current installation prefix of this module.   Relocation simply replaces a pathname starting with the original prefix   by the corresponding pathname with the current prefix instead.  Both   prefixes should be directory names without trailing slash (i.e. use ""   instead of "/").  */static voidset_this_relocation_prefix (const char *orig_prefix_arg,			    const char *curr_prefix_arg){  if (orig_prefix_arg != NULL && curr_prefix_arg != NULL      /* Optimization: if orig_prefix and curr_prefix are equal, the	 relocation is a nop.  */      && strcmp (orig_prefix_arg, curr_prefix_arg) != 0)    {      /* Duplicate the argument strings.  */      char *memory;      orig_prefix_len = strlen (orig_prefix_arg);      curr_prefix_len = strlen (curr_prefix_arg);      memory = (char *) xmalloc (orig_prefix_len + 1 + curr_prefix_len + 1);#ifdef NO_XMALLOC      if (memory != NULL)#endif	{	  memcpy (memory, orig_prefix_arg, orig_prefix_len + 1);	  orig_prefix = memory;	  memory += orig_prefix_len + 1;	  memcpy (memory, curr_prefix_arg, curr_prefix_len + 1);	  curr_prefix = memory;	  return;	}    }  orig_prefix = NULL;  curr_prefix = NULL;  /* Don't worry about wasted memory here - this function is usually only     called once.  */}/* Sets the original and the current installation prefix of the package.   Relocation simply replaces a pathname starting with the original prefix   by the corresponding pathname with the current prefix instead.  Both   prefixes should be directory names without trailing slash (i.e. use ""   instead of "/").  */voidset_relocation_prefix (const char *orig_prefix_arg, const char *curr_prefix_arg){  set_this_relocation_prefix (orig_prefix_arg, curr_prefix_arg);  /* Now notify all dependent libraries.  */#if DEPENDS_ON_LIBCHARSET  libcharset_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg);#endif#if DEPENDS_ON_LIBICONV && HAVE_ICONV && _LIBICONV_VERSION >= 0x0109  libiconv_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg);#endif#if DEPENDS_ON_LIBINTL && ENABLE_NLS && defined libintl_set_relocation_prefix  libintl_set_relocation_prefix (orig_prefix_arg, curr_prefix_arg);#endif}/* Convenience function:   Computes the current installation prefix, based on the original   installation prefix, the original installation directory of a particular   file, and the current pathname of this file.  Returns NULL upon failure.  */#ifdef IN_LIBRARY#define compute_curr_prefix local_compute_curr_prefixstatic#endifconst char *compute_curr_prefix (const char *orig_installprefix,		     const char *orig_installdir,		     const char *curr_pathname){  const char *curr_installdir;  const char *rel_installdir;  if (curr_pathname == NULL)    return NULL;  /* Determine the relative installation directory, relative to the prefix.     This is simply the difference between orig_installprefix and     orig_installdir.  */  if (strncmp (orig_installprefix, orig_installdir, strlen (orig_installprefix))      != 0)    /* Shouldn't happen - nothing should be installed outside $(prefix).  */    return NULL;  rel_installdir = orig_installdir + strlen (orig_installprefix);  /* Determine the current installation directory.  */  {    const char *p_base = curr_pathname + FILESYSTEM_PREFIX_LEN (curr_pathname);    const char *p = curr_pathname + strlen (curr_pathname);    char *q;    while (p > p_base)      {	p--;	if (ISSLASH (*p))	  break;      }    q = (char *) xmalloc (p - curr_pathname + 1);#ifdef NO_XMALLOC    if (q == NULL)      return NULL;#endif    memcpy (q, curr_pathname, p - curr_pathname);    q[p - curr_pathname] = '\0';    curr_installdir = q;  }  /* Compute the current installation prefix by removing the trailing     rel_installdir from it.  */  {    const char *rp = rel_installdir + strlen (rel_installdir);    const char *cp = curr_installdir + strlen (curr_installdir);    const char *cp_base =      curr_installdir + FILESYSTEM_PREFIX_LEN (curr_installdir);    while (rp > rel_installdir && cp > cp_base)      {	bool same = false;	const char *rpi = rp;	const char *cpi = cp;	while (rpi > rel_installdir && cpi > cp_base)	  {	    rpi--;	    cpi--;	    if (ISSLASH (*rpi) || ISSLASH (*cpi))	      {		if (ISSLASH (*rpi) && ISSLASH (*cpi))		  same = true;		break;	      }#if defined _WIN32 || defined __WIN32__ || defined __EMX__ || defined __DJGPP__	    /* Win32, OS/2, DOS - case insignificant filesystem */	    if ((*rpi >= 'a' && *rpi <= 'z' ? *rpi - 'a' + 'A' : *rpi)		!= (*cpi >= 'a' && *cpi <= 'z' ? *cpi - 'a' + 'A' : *cpi))	      break;#else	    if (*rpi != *cpi)	      break;#endif	  }	if (!same)	  break;	/* The last pathname component was the same.  opi and cpi now point	   to the slash before it.  */	rp = rpi;	cp = cpi;      }    if (rp > rel_installdir)      /* Unexpected: The curr_installdir does not end with rel_installdir.  */      return NULL;    {      size_t curr_prefix_len = cp - curr_installdir;      char *curr_prefix;      curr_prefix = (char *) xmalloc (curr_prefix_len + 1);#ifdef NO_XMALLOC      if (curr_prefix == NULL)	return NULL;#endif      memcpy (curr_prefix, curr_installdir, curr_prefix_len);      curr_prefix[curr_prefix_len] = '\0';      return curr_prefix;    }  }}#if defined PIC && defined INSTALLDIR/* Full pathname of shared library, or NULL.  */static char *shared_library_fullname;#if defined _WIN32 || defined __WIN32__/* Determine the full pathname of the shared library when it is loaded.  */BOOL WINAPIDllMain (HINSTANCE module_handle, DWORD event, LPVOID reserved){  (void) reserved;  if (event == DLL_PROCESS_ATTACH)    {      /* The DLL is being loaded into an application's address range.  */      static char location[MAX_PATH];      if (!GetModuleFileName (module_handle, location, sizeof (location)))	/* Shouldn't happen.  */	return FALSE;      if (!IS_PATH_WITH_DIR (location))	/* Shouldn't happen.  */	return FALSE;      shared_library_fullname = strdup (location);    }  return TRUE;}#else /* Unix */static voidfind_shared_library_fullname (){#ifdef __linux__  FILE *fp;  /* Open the current process' maps file.  It describes one VMA per line.  */  fp = fopen ("/proc/self/maps", "r");  if (fp)    {      unsigned long address = (unsigned long) &find_shared_library_fullname;      for (;;)	{	  unsigned long start, end;	  int c;	  if (fscanf (fp, "%lx-%lx", &start, &end) != 2)	    break;	  if (address >= start && address <= end - 1)	    {	      /* Found it.  Now see if this line contains a filename.  */	      while (c = getc (fp), c != EOF && c != '\n' && c != '/')		continue;	      if (c == '/')		{		  size_t size;		  int len;		  ungetc (c, fp);		  shared_library_fullname = NULL; size = 0;		  len = getline (&shared_library_fullname, &size, fp);		  if (len >= 0)		    {		      /* Success: filled shared_library_fullname.  */		      if (len > 0 && shared_library_fullname[len - 1] == '\n')			shared_library_fullname[len - 1] = '\0';		    }		}	      break;	    }	  while (c = getc (fp), c != EOF && c != '\n')	    continue;	}      fclose (fp);    }#endif}#endif /* WIN32 / Unix *//* Return the full pathname of the current shared library.   Return NULL if unknown.   Guaranteed to work only on Linux and Woe32.  */static char *get_shared_library_fullname (){#if !(defined _WIN32 || defined __WIN32__)  static bool tried_find_shared_library_fullname;  if (!tried_find_shared_library_fullname)    {      find_shared_library_fullname ();      tried_find_shared_library_fullname = true;    }#endif  return shared_library_fullname;}#endif /* PIC *//* Returns the pathname, relocated according to the current installation   directory.  */const char *relocate (const char *pathname){#if defined PIC && defined INSTALLDIR  static int initialized;  /* Initialization code for a shared library.  */  if (!initialized)    {      /* At this point, orig_prefix and curr_prefix likely have already been	 set through the main program's set_program_name_and_installdir	 function.  This is sufficient in the case that the library has	 initially been installed in the same orig_prefix.  But we can do	 better, to also cover the cases that 1. it has been installed	 in a different prefix before being moved to orig_prefix and (later)	 to curr_prefix, 2. unlike the program, it has not moved away from	 orig_prefix.  */      const char *orig_installprefix = INSTALLPREFIX;      const char *orig_installdir = INSTALLDIR;      const char *curr_prefix_better;      curr_prefix_better =	compute_curr_prefix (orig_installprefix, orig_installdir,			     get_shared_library_fullname ());      if (curr_prefix_better == NULL)	curr_prefix_better = curr_prefix;      set_relocation_prefix (orig_installprefix, curr_prefix_better);      initialized = 1;    }#endif  /* Note: It is not necessary to perform case insensitive comparison here,     even for DOS-like filesystems, because the pathname argument was     typically created from the same Makefile variable as orig_prefix came     from.  */  if (orig_prefix != NULL && curr_prefix != NULL      && strncmp (pathname, orig_prefix, orig_prefix_len) == 0)    {      if (pathname[orig_prefix_len] == '\0')	/* pathname equals orig_prefix.  */	return curr_prefix;      if (ISSLASH (pathname[orig_prefix_len]))	{	  /* pathname starts with orig_prefix.  */	  const char *pathname_tail = &pathname[orig_prefix_len];	  char *result =	    (char *) xmalloc (curr_prefix_len + strlen (pathname_tail) + 1);#ifdef NO_XMALLOC	  if (result != NULL)#endif	    {	      memcpy (result, curr_prefix, curr_prefix_len);	      strcpy (result + curr_prefix_len, pathname_tail);	      return result;	    }	}    }  /* Nothing to relocate.  */  return pathname;}#endif