[GNUnet-SVN] r23948 - Extractor/src/main

[gnunet]

Author: grothoff
Date: 2012-09-22 22:10:13 +0200 (Sat, 22 Sep 2012)
New Revision: 23948

Modified:
   Extractor/src/main/extractor_plugpath.c
Log:
-dos2unix

Modified: Extractor/src/main/extractor_plugpath.c
===================================================================
--- Extractor/src/main/extractor_plugpath.c     2012-09-22 20:04:16 UTC (rev 
23947)
+++ Extractor/src/main/extractor_plugpath.c     2012-09-22 20:10:13 UTC (rev 
23948)
@@ -1,663 +1,663 @@
-/*
-     This file is part of libextractor.
-     (C) 2002, 2003, 2004, 2005, 2006, 2009, 2012 Vidyut Samanta and Christian 
Grothoff
-
-     libextractor is free software; you can redistribute it and/or modify
-     it under the terms of the GNU General Public License as published
-     by the Free Software Foundation; either version 3, or (at your
-     option) any later version.
-
-     libextractor 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
-     General Public License for more details.
-
-     You should have received a copy of the GNU General Public License
-     along with libextractor; see the file COPYING.  If not, write to the
-     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
-     Boston, MA 02111-1307, USA.
- */
-/**
- * @file main/extractor_plugpath.c
- * @brief determine path where plugins are installed
- * @author Christian Grothoff
- */
-
-#include "platform.h"
-#include "plibc.h"
-#include "extractor.h"
-#include <dirent.h>
-#include <sys/types.h>
-#include <signal.h>
-#include <ltdl.h>
-
-#include "extractor_plugpath.h"
-#include "extractor_logging.h"
-
-/**
- * Function to call on paths.
- * 
- * @param cls closure
- * @param path a directory path
- */
-typedef void (*EXTRACTOR_PathProcessor) (void *cls,
-                                        const char *path);
-
-
-/**
- * Remove a trailing '/bin/' from 'in' (if present).
- *
- * @param in input string, modified
- * @return NULL if 'in' is NULL, otherwise 'in' with '/bin/' removed
- */
-static char * 
-cut_bin (char * in) 
-{
-  size_t p;
-
-  if (NULL == in)
-    return NULL;
-  p = strlen (in);
-  if (p < 4)
-    return in;
-  if ( ('/' == in[p-1]) ||
-       ('\\' == in[p-1]) )
-    in[--p] = '\0';
-  if (0 == strcmp (&in[p-4],
-                  "/bin")) 
-    {
-      in[p-4] = '\0';
-      p -= 4;
-    }
-  else if (0 == strcmp (&in[p-4],
-                       "\\bin"))
-    {
-      in[p-4] = '\0';
-      p -= 4;
-    }
-  return in;
-}
-
-
-#if GNU_LINUX
-/**
- * Try to determine path by reading /proc/PID/exe or
- * /proc/PID/maps.
- *
- * Note that this may fail if LE is installed in one directory
- * and the binary linking against it sits elsewhere.
- */
-static char *
-get_path_from_proc_exe () 
-{
-  char fn[64];
-  char line[1024];
-  char dir[1024];
-  char *lnk;
-  char *ret;
-  char *lestr;
-  ssize_t size;
-  FILE *f;
-
-  snprintf (fn,
-           sizeof (fn),
-           "/proc/%u/maps",
-           getpid ());
-  if (NULL != (f = FOPEN (fn, "r")))
-    {
-      while (NULL != fgets (line, 1024, f)) 
-       {
-         if ( (1 == sscanf (line,
-                            "%*x-%*x %*c%*c%*c%*c %*x %*2x:%*2x %*u%*[ ]%s",
-                            dir)) &&
-              (NULL != (lestr = strstr (dir,
-                                        "libextractor")) ) ) 
-           {
-             lestr[0] = '\0';
-             fclose (f);
-             return strdup (dir);
-           }
-       }
-      fclose (f);
-    }
-  snprintf (fn,
-           sizeof (fn),
-           "/proc/%u/exe",
-           getpid ());
-  if (NULL == (lnk = malloc (1029))) /* 1024 + 6 for "/lib/" catenation */
-    return NULL;
-  size = readlink (fn, lnk, 1023);
-  if ( (size <= 0) || (size >= 1024) )
-    {
-      free (lnk);
-      return NULL;
-    }
-  lnk[size] = '\0';
-  while ( ('/' != lnk[size]) &&
-         (size > 0) )
-    size--;
-  if ( (size < 4) ||
-       ('/' != lnk[size-4]) )
-    {
-      /* not installed in "/bin/" -- binary path probably useless */
-      free (lnk);
-      return NULL;
-    }
-  lnk[size] = '\0';
-  lnk = cut_bin (lnk);
-  if (NULL == (ret = realloc (lnk, strlen(lnk) + 6)))
-    {
-      LOG_STRERROR ("realloc");
-      free (lnk);
-      return NULL;
-    }
-  strcat (ret, "/lib/"); /* guess "lib/" as the library dir */
-  return ret;
-}
-#endif
-
-
-#if WINDOWS
-/**
- * Try to determine path with win32-specific function
- */
-static char * 
-get_path_from_module_filename () 
-{
-  char *path;
-  char *ret;
-  char *idx;
-
-  if (NULL == (path = malloc (4103))) /* 4096+nil+6 for "/lib/" catenation */
-    return NULL;
-  GetModuleFileName (NULL, path, 4096);
-  idx = path + strlen (path);
-  while ( (idx > path) &&
-         ('\\' != *idx) &&
-         ('/' != *idx) )
-    idx--;
-  *idx = '\0';
-  path = cut_bin (path);
-  if (NULL == (ret = realloc (path, strlen(path) + 6)))
-    {
-      LOG_STRERROR ("realloc");
-      free (path);
-      return NULL;
-    }
-  strcat (ret, "/lib/"); /* guess "lib/" as the library dir */
-  return ret;
-}
-#endif
-
-
-#if DARWIN
-#include <dlfcn.h>
-#include <mach-o/dyld.h>
-
-/**
- * Signature of the '_NSGetExecutablePath" function.
- *
- * @param buf where to write the path
- * @param number of bytes available in 'buf'
- * @return 0 on success, otherwise desired number of bytes is stored in 
'bufsize'
- */
-typedef int (*MyNSGetExecutablePathProto) (char *buf, 
-                                          size_t *bufsize);
-
-
-/**
- * Try to obtain the path of our executable using '_NSGetExecutablePath'.
- *
- * @return NULL on error
- */
-static char *
-get_path_from_NSGetExecutablePath ()
-{
-  static char zero;
-  char *path;
-  size_t len;
-  MyNSGetExecutablePathProto func;
-
-  path = NULL;
-  if (NULL == (func =
-              (MyNSGetExecutablePathProto) dlsym (RTLD_DEFAULT,
-                                                  "_NSGetExecutablePath")))
-    return NULL;
-  path = &zero;
-  len = 0;
-  /* get the path len, including the trailing \0 */
-  (void) func (path, &len);
-  if (0 == len)
-    return NULL;
-  if (NULL == (path = malloc (len)))
-    {
-      LOG_STRERROR ("malloc");
-      return NULL;
-    }
-  if (0 != func (path, &len))
-  {
-    GNUNET_free (path);
-    return NULL;
-  }
-  len = strlen (path);
-  while ((path[len] != '/') && (len > 0))
-    len--;
-  path[len] = '\0';
-  return path;
-}
-
-
-/**
- * Try to obtain the path of our executable using '_dyld_image' API.
- *
- * @return NULL on error
- */
-static char * 
-get_path_from_dyld_image () 
-{
-  const char *path;
-  char *s;
-  char *p;
-  unsigned int i;
-  int c;
-
-  c = _dyld_image_count ();
-  for (i = 0; i < c; i++) 
-    {
-      if (((void *) _dyld_get_image_header (i)) != (void *) &_mh_dylib_header)
-       continue;
-      path = _dyld_get_image_name (i);
-      if ( (NULL == path) || (0 == strlen (path)) )
-       continue;
-      if (NULL == (p = strdup (path)))
-       {
-         LOG_STRERROR ("strdup");
-         return NULL;
-       }
-      s = p + strlen (p);
-      while ( (s > p) && ('/' != *s) )
-       s--;
-      s++;
-      *s = '\0';
-      return p;
-    }
-  return NULL;
-}
-#endif
-
-
-/**
- * Return the actual path to a file found in the current
- * PATH environment variable.
- *
- * @return path to binary, NULL if not found
- */
-static char *
-get_path_from_PATH() {
-  struct stat sbuf;
-  char *path;
-  char *pos;
-  char *end;
-  char *buf;
-  char *ret;
-  const char *p;
-
-  if (NULL == (p = getenv ("PATH")))
-    return NULL;
-  if (NULL == (path = strdup (p))) /* because we write on it */
-    {
-      LOG_STRERROR ("strdup");
-      return NULL;
-    }
-  if (NULL == (buf = malloc (strlen (path) + 20)))
-    {
-      LOG_STRERROR ("malloc");
-      free (path);
-      return NULL;
-    }
-  pos = path;
-  while (NULL != (end = strchr(pos, ':'))) 
-    {
-      *end = '\0';
-      sprintf (buf, "%s/%s", pos, "extract");
-      if (0 == stat(buf, &sbuf)) 
-       {
-         free (buf);
-         if (NULL == (pos = strdup (pos)))
-           {
-             LOG_STRERROR ("strdup");
-             free (path);
-             return NULL;
-           }
-         free (path);
-         pos = cut_bin (pos);
-         if (NULL == (ret = realloc (pos, strlen (pos) + 5)))
-           {
-             LOG_STRERROR ("realloc");
-             free (pos);
-             return NULL;
-           }
-         strcat (ret, "lib/");
-         return ret;
-       }
-      pos = end + 1;
-    }
-  sprintf (buf, "%s/%s", pos, "extract");
-  if (0 == stat (buf, &sbuf)) 
-    {
-      pos = strdup (pos);
-      free (buf);
-      free (path);
-      if (NULL == pos)
-       return NULL;
-      pos = cut_bin (pos);
-      if (NULL == (ret = realloc (pos, strlen (pos) + 5)))
-       {
-         LOG_STRERROR ("realloc");
-         free (pos);
-         return NULL;
-       }
-      strcat (ret, "lib/");
-      return ret;
-    }
-  free (buf);
-  free (path);
-  return NULL;
-}
-
-
-/**
- * Create a filename by appending 'fname' to 'path'.
- *
- * @param path the base path 
- * @param fname the filename to append
- * @return '$path/$fname', NULL on error
- */
-static char *
-append_to_dir (const char *path,
-              const char *fname)
-{
-  char *ret;
-  size_t slen;
-
-  if (0 == (slen = strlen (path)))
-    return NULL;
-  if (DIR_SEPARATOR == fname[0])
-    fname++;
-  ret = malloc (slen + strlen(fname) + 2);
-  if (NULL == ret)
-    return NULL;
-#ifdef MINGW
-  if ('\\' == path[slen-1])
-    sprintf (ret,
-            "%s%s",
-            path, 
-            fname);
-  else
-    sprintf (ret,
-            "%s\\%s",
-            path, 
-            fname);
-#else
-  if ('/' == path[slen-1])
-    sprintf (ret,
-            "%s%s",
-            path, 
-            fname);
-  else
-    sprintf (ret,
-            "%s/%s",
-            path, 
-            fname);
-#endif
-  return ret;
-}
-
-
-/**
- * Iterate over all paths where we expect to find GNU libextractor
- * plugins.
- *
- * @param pp function to call for each path
- * @param pp_cls cls argument for pp.
- */
-static void
-get_installation_paths (EXTRACTOR_PathProcessor pp,
-                       void *pp_cls)
-{
-  const char *p;
-  char *path;
-  char *prefix;
-  char *d;
-  char *saveptr;
-
-  prefix = NULL;
-  if (NULL != (p = getenv ("LIBEXTRACTOR_PREFIX")))
-    {
-      if (NULL == (d = strdup (p)))
-       {
-         LOG_STRERROR ("strdup");
-         return;
-       }
-      for (prefix = strtok_r (d, PATH_SEPARATOR_STR, &saveptr);
-          NULL != prefix;
-          prefix = strtok_r (NULL, PATH_SEPARATOR_STR, &saveptr))
-       pp (pp_cls, prefix);    
-      free (d);
-      return;
-    }
-#if GNU_LINUX
-  if (NULL == prefix)
-    prefix = get_path_from_proc_exe ();
-#endif
-#if WINDOWS
-  if (NULL == prefix)
-    prefix = get_path_from_module_filename ();
-#endif
-#if DARWIN
-  if (NULL == prefix)
-    prefix = get_path_from_NSGetExecutablePath ();
-  if (NULL == prefix)
-    prefix = get_path_from_dyld_image ();
-#endif
-  if (NULL == prefix)
-    prefix = get_path_from_PATH ();
-  pp (pp_cls, PLUGININSTDIR);
-  if (NULL == prefix)
-    return;
-  path = append_to_dir (prefix, PLUGINDIR);
-  if (NULL != path)
-    {
-      if (0 != strcmp (path,
-                      PLUGININSTDIR))
-       pp (pp_cls, path);
-      free (path);
-    }
-  free (prefix);
-}
-
-
-/**
- * Closure for 'find_plugin_in_path'.
- */
-struct SearchContext
-{
-  /**
-   * Name of the plugin we are looking for.
-   */
-  const char *short_name;
-  
-  /**
-   * Location for storing the path to the plugin upon success.
-   */ 
-  char *path;
-};
-
-
-/**
- * Load all plugins from the given directory.
- * 
- * @param cls pointer to the "struct EXTRACTOR_PluginList*" to extend
- * @param path path to a directory with plugins
- */
-static void
-find_plugin_in_path (void *cls,
-                    const char *path)
-{
-  struct SearchContext *sc = cls;
-  DIR *dir;
-  struct dirent *ent;
-  const char *sym_name;
-  char *sym;
-  char *dot;
-  size_t dlen;
-
-  if (NULL != sc->path)
-    return;
-  if (NULL == (dir = OPENDIR (path)))
-    return;
-  while (NULL != (ent = READDIR (dir)))
-    {
-      if ('.' == ent->d_name[0])
-       continue;
-      dlen = strlen (ent->d_name);
-      if ( (dlen < 4) ||
-          ( (0 != strcmp (&ent->d_name[dlen-3], ".so")) &&
-            (0 != strcasecmp (&ent->d_name[dlen-4], ".dll")) ) )
-       continue; /* only load '.so' and '.dll' */
-      if (NULL == (sym_name = strrchr (ent->d_name, '_')))
-       continue;       
-      sym_name++;
-      if (NULL == (sym = strdup (sym_name)))
-       {
-         LOG_STRERROR ("strdup");
-         CLOSEDIR (dir);
-         return;
-       }
-      dot = strchr (sym, '.');
-      if (NULL != dot)
-       *dot = '\0';
-      if (0 == strcmp (sym, sc->short_name))
-       {
-         sc->path = append_to_dir (path, ent->d_name);
-         free (sym);
-         break;
-       }
-      free (sym);
-    }
-  CLOSEDIR (dir);
-}
-
-
-/**
- * Given a short name of a library (i.e. "mime"), find
- * the full path of the respective plugin.
- */
-char *
-EXTRACTOR_find_plugin_ (const char *short_name)
-{
-  struct SearchContext sc;
-  
-  sc.path = NULL;
-  sc.short_name = short_name;
-  get_installation_paths (&find_plugin_in_path,
-                         &sc);
-  return sc.path;
-}
-
-
-/** 
- * Closure for 'load_plugins_from_dir'.
- */
-struct DefaultLoaderContext
-{
-  /**
-   * Accumulated result list.
-   */ 
-  struct EXTRACTOR_PluginList *res;
-
-  /**
-   * Flags to use for all plugins.
-   */
-  enum EXTRACTOR_Options flags;
-};
-
-
-/**
- * Load all plugins from the given directory.
- * 
- * @param cls pointer to the "struct EXTRACTOR_PluginList*" to extend
- * @param path path to a directory with plugins
- */
-static void
-load_plugins_from_dir (void *cls,
-                      const char *path)
-{
-  struct DefaultLoaderContext *dlc = cls;
-  DIR *dir;
-  struct dirent *ent;
-  const char *sym_name;
-  char *sym;
-  char *dot;
-  size_t dlen;
-
-  if (NULL == (dir = opendir (path)))
-    return;
-  while (NULL != (ent = readdir (dir)))
-    {
-      if (ent->d_name[0] == '.')
-       continue;
-      dlen = strlen (ent->d_name);
-      if ( (dlen < 4) ||
-          ( (0 != strcmp (&ent->d_name[dlen-3], ".so")) &&
-            (0 != strcasecmp (&ent->d_name[dlen-4], ".dll")) ) )
-       continue; /* only load '.so' and '.dll' */
-      if (NULL == (sym_name = strrchr (ent->d_name, '_')))
-       continue;
-      sym_name++;
-      if (NULL == (sym = strdup (sym_name)))
-       {
-         LOG_STRERROR ("strdup");
-         closedir (dir);
-         return;
-       }
-      if (NULL != (dot = strchr (sym, '.')))
-       *dot = '\0';
-      dlc->res = EXTRACTOR_plugin_add (dlc->res,
-                                      sym,
-                                      NULL,
-                                      dlc->flags);
-      free (sym);
-    }
-  closedir (dir);
-}
-
-
-/**
- * Load the default set of plugins. The default can be changed
- * by setting the LIBEXTRACTOR_LIBRARIES environment variable.
- * If it is set to "env", then this function will return
- * EXTRACTOR_plugin_add_config (NULL, env, flags).  Otherwise,
- * it will load all of the installed plugins and return them.
- *
- * @param flags options for all of the plugins loaded
- * @return the default set of plugins, NULL if no plugins were found
- */
-struct EXTRACTOR_PluginList * 
-EXTRACTOR_plugin_add_defaults (enum EXTRACTOR_Options flags)
-{
-  struct DefaultLoaderContext dlc;
-  char *env;
-
-  env = getenv ("LIBEXTRACTOR_LIBRARIES");
-  if (NULL != env)
-    return EXTRACTOR_plugin_add_config (NULL, env, flags);
-  dlc.res = NULL;
-  dlc.flags = flags;
-  get_installation_paths (&load_plugins_from_dir,
-                         &dlc);
-  return dlc.res;
-}
-
-
-/* end of extractor_plugpath.c */
+/*
+     This file is part of libextractor.
+     (C) 2002, 2003, 2004, 2005, 2006, 2009, 2012 Vidyut Samanta and Christian 
Grothoff
+
+     libextractor is free software; you can redistribute it and/or modify
+     it under the terms of the GNU General Public License as published
+     by the Free Software Foundation; either version 3, or (at your
+     option) any later version.
+
+     libextractor 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
+     General Public License for more details.
+
+     You should have received a copy of the GNU General Public License
+     along with libextractor; see the file COPYING.  If not, write to the
+     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
+     Boston, MA 02111-1307, USA.
+ */
+/**
+ * @file main/extractor_plugpath.c
+ * @brief determine path where plugins are installed
+ * @author Christian Grothoff
+ */
+
+#include "platform.h"
+#include "plibc.h"
+#include "extractor.h"
+#include <dirent.h>
+#include <sys/types.h>
+#include <signal.h>
+#include <ltdl.h>
+
+#include "extractor_plugpath.h"
+#include "extractor_logging.h"
+
+/**
+ * Function to call on paths.
+ * 
+ * @param cls closure
+ * @param path a directory path
+ */
+typedef void (*EXTRACTOR_PathProcessor) (void *cls,
+                                        const char *path);
+
+
+/**
+ * Remove a trailing '/bin/' from 'in' (if present).
+ *
+ * @param in input string, modified
+ * @return NULL if 'in' is NULL, otherwise 'in' with '/bin/' removed
+ */
+static char * 
+cut_bin (char * in) 
+{
+  size_t p;
+
+  if (NULL == in)
+    return NULL;
+  p = strlen (in);
+  if (p < 4)
+    return in;
+  if ( ('/' == in[p-1]) ||
+       ('\\' == in[p-1]) )
+    in[--p] = '\0';
+  if (0 == strcmp (&in[p-4],
+                  "/bin")) 
+    {
+      in[p-4] = '\0';
+      p -= 4;
+    }
+  else if (0 == strcmp (&in[p-4],
+                       "\\bin"))
+    {
+      in[p-4] = '\0';
+      p -= 4;
+    }
+  return in;
+}
+
+
+#if GNU_LINUX
+/**
+ * Try to determine path by reading /proc/PID/exe or
+ * /proc/PID/maps.
+ *
+ * Note that this may fail if LE is installed in one directory
+ * and the binary linking against it sits elsewhere.
+ */
+static char *
+get_path_from_proc_exe () 
+{
+  char fn[64];
+  char line[1024];
+  char dir[1024];
+  char *lnk;
+  char *ret;
+  char *lestr;
+  ssize_t size;
+  FILE *f;
+
+  snprintf (fn,
+           sizeof (fn),
+           "/proc/%u/maps",
+           getpid ());
+  if (NULL != (f = FOPEN (fn, "r")))
+    {
+      while (NULL != fgets (line, 1024, f)) 
+       {
+         if ( (1 == sscanf (line,
+                            "%*x-%*x %*c%*c%*c%*c %*x %*2x:%*2x %*u%*[ ]%s",
+                            dir)) &&
+              (NULL != (lestr = strstr (dir,
+                                        "libextractor")) ) ) 
+           {
+             lestr[0] = '\0';
+             fclose (f);
+             return strdup (dir);
+           }
+       }
+      fclose (f);
+    }
+  snprintf (fn,
+           sizeof (fn),
+           "/proc/%u/exe",
+           getpid ());
+  if (NULL == (lnk = malloc (1029))) /* 1024 + 6 for "/lib/" catenation */
+    return NULL;
+  size = readlink (fn, lnk, 1023);
+  if ( (size <= 0) || (size >= 1024) )
+    {
+      free (lnk);
+      return NULL;
+    }
+  lnk[size] = '\0';
+  while ( ('/' != lnk[size]) &&
+         (size > 0) )
+    size--;
+  if ( (size < 4) ||
+       ('/' != lnk[size-4]) )
+    {
+      /* not installed in "/bin/" -- binary path probably useless */
+      free (lnk);
+      return NULL;
+    }
+  lnk[size] = '\0';
+  lnk = cut_bin (lnk);
+  if (NULL == (ret = realloc (lnk, strlen(lnk) + 6)))
+    {
+      LOG_STRERROR ("realloc");
+      free (lnk);
+      return NULL;
+    }
+  strcat (ret, "/lib/"); /* guess "lib/" as the library dir */
+  return ret;
+}
+#endif
+
+
+#if WINDOWS
+/**
+ * Try to determine path with win32-specific function
+ */
+static char * 
+get_path_from_module_filename () 
+{
+  char *path;
+  char *ret;
+  char *idx;
+
+  if (NULL == (path = malloc (4103))) /* 4096+nil+6 for "/lib/" catenation */
+    return NULL;
+  GetModuleFileName (NULL, path, 4096);
+  idx = path + strlen (path);
+  while ( (idx > path) &&
+         ('\\' != *idx) &&
+         ('/' != *idx) )
+    idx--;
+  *idx = '\0';
+  path = cut_bin (path);
+  if (NULL == (ret = realloc (path, strlen(path) + 6)))
+    {
+      LOG_STRERROR ("realloc");
+      free (path);
+      return NULL;
+    }
+  strcat (ret, "/lib/"); /* guess "lib/" as the library dir */
+  return ret;
+}
+#endif
+
+
+#if DARWIN
+#include <dlfcn.h>
+#include <mach-o/dyld.h>
+
+/**
+ * Signature of the '_NSGetExecutablePath" function.
+ *
+ * @param buf where to write the path
+ * @param number of bytes available in 'buf'
+ * @return 0 on success, otherwise desired number of bytes is stored in 
'bufsize'
+ */
+typedef int (*MyNSGetExecutablePathProto) (char *buf, 
+                                          size_t *bufsize);
+
+
+/**
+ * Try to obtain the path of our executable using '_NSGetExecutablePath'.
+ *
+ * @return NULL on error
+ */
+static char *
+get_path_from_NSGetExecutablePath ()
+{
+  static char zero;
+  char *path;
+  size_t len;
+  MyNSGetExecutablePathProto func;
+
+  path = NULL;
+  if (NULL == (func =
+              (MyNSGetExecutablePathProto) dlsym (RTLD_DEFAULT,
+                                                  "_NSGetExecutablePath")))
+    return NULL;
+  path = &zero;
+  len = 0;
+  /* get the path len, including the trailing \0 */
+  (void) func (path, &len);
+  if (0 == len)
+    return NULL;
+  if (NULL == (path = malloc (len)))
+    {
+      LOG_STRERROR ("malloc");
+      return NULL;
+    }
+  if (0 != func (path, &len))
+  {
+    free (path);
+    return NULL;
+  }
+  len = strlen (path);
+  while ((path[len] != '/') && (len > 0))
+    len--;
+  path[len] = '\0';
+  return path;
+}
+
+
+/**
+ * Try to obtain the path of our executable using '_dyld_image' API.
+ *
+ * @return NULL on error
+ */
+static char * 
+get_path_from_dyld_image () 
+{
+  const char *path;
+  char *s;
+  char *p;
+  unsigned int i;
+  int c;
+
+  c = _dyld_image_count ();
+  for (i = 0; i < c; i++) 
+    {
+      if (((void *) _dyld_get_image_header (i)) != (void *) &_mh_dylib_header)
+       continue;
+      path = _dyld_get_image_name (i);
+      if ( (NULL == path) || (0 == strlen (path)) )
+       continue;
+      if (NULL == (p = strdup (path)))
+       {
+         LOG_STRERROR ("strdup");
+         return NULL;
+       }
+      s = p + strlen (p);
+      while ( (s > p) && ('/' != *s) )
+       s--;
+      s++;
+      *s = '\0';
+      return p;
+    }
+  return NULL;
+}
+#endif
+
+
+/**
+ * Return the actual path to a file found in the current
+ * PATH environment variable.
+ *
+ * @return path to binary, NULL if not found
+ */
+static char *
+get_path_from_PATH() {
+  struct stat sbuf;
+  char *path;
+  char *pos;
+  char *end;
+  char *buf;
+  char *ret;
+  const char *p;
+
+  if (NULL == (p = getenv ("PATH")))
+    return NULL;
+  if (NULL == (path = strdup (p))) /* because we write on it */
+    {
+      LOG_STRERROR ("strdup");
+      return NULL;
+    }
+  if (NULL == (buf = malloc (strlen (path) + 20)))
+    {
+      LOG_STRERROR ("malloc");
+      free (path);
+      return NULL;
+    }
+  pos = path;
+  while (NULL != (end = strchr(pos, ':'))) 
+    {
+      *end = '\0';
+      sprintf (buf, "%s/%s", pos, "extract");
+      if (0 == stat(buf, &sbuf)) 
+       {
+         free (buf);
+         if (NULL == (pos = strdup (pos)))
+           {
+             LOG_STRERROR ("strdup");
+             free (path);
+             return NULL;
+           }
+         free (path);
+         pos = cut_bin (pos);
+         if (NULL == (ret = realloc (pos, strlen (pos) + 5)))
+           {
+             LOG_STRERROR ("realloc");
+             free (pos);
+             return NULL;
+           }
+         strcat (ret, "lib/");
+         return ret;
+       }
+      pos = end + 1;
+    }
+  sprintf (buf, "%s/%s", pos, "extract");
+  if (0 == stat (buf, &sbuf)) 
+    {
+      pos = strdup (pos);
+      free (buf);
+      free (path);
+      if (NULL == pos)
+       return NULL;
+      pos = cut_bin (pos);
+      if (NULL == (ret = realloc (pos, strlen (pos) + 5)))
+       {
+         LOG_STRERROR ("realloc");
+         free (pos);
+         return NULL;
+       }
+      strcat (ret, "lib/");
+      return ret;
+    }
+  free (buf);
+  free (path);
+  return NULL;
+}
+
+
+/**
+ * Create a filename by appending 'fname' to 'path'.
+ *
+ * @param path the base path 
+ * @param fname the filename to append
+ * @return '$path/$fname', NULL on error
+ */
+static char *
+append_to_dir (const char *path,
+              const char *fname)
+{
+  char *ret;
+  size_t slen;
+
+  if (0 == (slen = strlen (path)))
+    return NULL;
+  if (DIR_SEPARATOR == fname[0])
+    fname++;
+  ret = malloc (slen + strlen(fname) + 2);
+  if (NULL == ret)
+    return NULL;
+#ifdef MINGW
+  if ('\\' == path[slen-1])
+    sprintf (ret,
+            "%s%s",
+            path, 
+            fname);
+  else
+    sprintf (ret,
+            "%s\\%s",
+            path, 
+            fname);
+#else
+  if ('/' == path[slen-1])
+    sprintf (ret,
+            "%s%s",
+            path, 
+            fname);
+  else
+    sprintf (ret,
+            "%s/%s",
+            path, 
+            fname);
+#endif
+  return ret;
+}
+
+
+/**
+ * Iterate over all paths where we expect to find GNU libextractor
+ * plugins.
+ *
+ * @param pp function to call for each path
+ * @param pp_cls cls argument for pp.
+ */
+static void
+get_installation_paths (EXTRACTOR_PathProcessor pp,
+                       void *pp_cls)
+{
+  const char *p;
+  char *path;
+  char *prefix;
+  char *d;
+  char *saveptr;
+
+  prefix = NULL;
+  if (NULL != (p = getenv ("LIBEXTRACTOR_PREFIX")))
+    {
+      if (NULL == (d = strdup (p)))
+       {
+         LOG_STRERROR ("strdup");
+         return;
+       }
+      for (prefix = strtok_r (d, PATH_SEPARATOR_STR, &saveptr);
+          NULL != prefix;
+          prefix = strtok_r (NULL, PATH_SEPARATOR_STR, &saveptr))
+       pp (pp_cls, prefix);    
+      free (d);
+      return;
+    }
+#if GNU_LINUX
+  if (NULL == prefix)
+    prefix = get_path_from_proc_exe ();
+#endif
+#if WINDOWS
+  if (NULL == prefix)
+    prefix = get_path_from_module_filename ();
+#endif
+#if DARWIN
+  if (NULL == prefix)
+    prefix = get_path_from_NSGetExecutablePath ();
+  if (NULL == prefix)
+    prefix = get_path_from_dyld_image ();
+#endif
+  if (NULL == prefix)
+    prefix = get_path_from_PATH ();
+  pp (pp_cls, PLUGININSTDIR);
+  if (NULL == prefix)
+    return;
+  path = append_to_dir (prefix, PLUGINDIR);
+  if (NULL != path)
+    {
+      if (0 != strcmp (path,
+                      PLUGININSTDIR))
+       pp (pp_cls, path);
+      free (path);
+    }
+  free (prefix);
+}
+
+
+/**
+ * Closure for 'find_plugin_in_path'.
+ */
+struct SearchContext
+{
+  /**
+   * Name of the plugin we are looking for.
+   */
+  const char *short_name;
+  
+  /**
+   * Location for storing the path to the plugin upon success.
+   */ 
+  char *path;
+};
+
+
+/**
+ * Load all plugins from the given directory.
+ * 
+ * @param cls pointer to the "struct EXTRACTOR_PluginList*" to extend
+ * @param path path to a directory with plugins
+ */
+static void
+find_plugin_in_path (void *cls,
+                    const char *path)
+{
+  struct SearchContext *sc = cls;
+  DIR *dir;
+  struct dirent *ent;
+  const char *sym_name;
+  char *sym;
+  char *dot;
+  size_t dlen;
+
+  if (NULL != sc->path)
+    return;
+  if (NULL == (dir = OPENDIR (path)))
+    return;
+  while (NULL != (ent = READDIR (dir)))
+    {
+      if ('.' == ent->d_name[0])
+       continue;
+      dlen = strlen (ent->d_name);
+      if ( (dlen < 4) ||
+          ( (0 != strcmp (&ent->d_name[dlen-3], ".so")) &&
+            (0 != strcasecmp (&ent->d_name[dlen-4], ".dll")) ) )
+       continue; /* only load '.so' and '.dll' */
+      if (NULL == (sym_name = strrchr (ent->d_name, '_')))
+       continue;       
+      sym_name++;
+      if (NULL == (sym = strdup (sym_name)))
+       {
+         LOG_STRERROR ("strdup");
+         CLOSEDIR (dir);
+         return;
+       }
+      dot = strchr (sym, '.');
+      if (NULL != dot)
+       *dot = '\0';
+      if (0 == strcmp (sym, sc->short_name))
+       {
+         sc->path = append_to_dir (path, ent->d_name);
+         free (sym);
+         break;
+       }
+      free (sym);
+    }
+  CLOSEDIR (dir);
+}
+
+
+/**
+ * Given a short name of a library (i.e. "mime"), find
+ * the full path of the respective plugin.
+ */
+char *
+EXTRACTOR_find_plugin_ (const char *short_name)
+{
+  struct SearchContext sc;
+  
+  sc.path = NULL;
+  sc.short_name = short_name;
+  get_installation_paths (&find_plugin_in_path,
+                         &sc);
+  return sc.path;
+}
+
+
+/** 
+ * Closure for 'load_plugins_from_dir'.
+ */
+struct DefaultLoaderContext
+{
+  /**
+   * Accumulated result list.
+   */ 
+  struct EXTRACTOR_PluginList *res;
+
+  /**
+   * Flags to use for all plugins.
+   */
+  enum EXTRACTOR_Options flags;
+};
+
+
+/**
+ * Load all plugins from the given directory.
+ * 
+ * @param cls pointer to the "struct EXTRACTOR_PluginList*" to extend
+ * @param path path to a directory with plugins
+ */
+static void
+load_plugins_from_dir (void *cls,
+                      const char *path)
+{
+  struct DefaultLoaderContext *dlc = cls;
+  DIR *dir;
+  struct dirent *ent;
+  const char *sym_name;
+  char *sym;
+  char *dot;
+  size_t dlen;
+
+  if (NULL == (dir = opendir (path)))
+    return;
+  while (NULL != (ent = readdir (dir)))
+    {
+      if (ent->d_name[0] == '.')
+       continue;
+      dlen = strlen (ent->d_name);
+      if ( (dlen < 4) ||
+          ( (0 != strcmp (&ent->d_name[dlen-3], ".so")) &&
+            (0 != strcasecmp (&ent->d_name[dlen-4], ".dll")) ) )
+       continue; /* only load '.so' and '.dll' */
+      if (NULL == (sym_name = strrchr (ent->d_name, '_')))
+       continue;
+      sym_name++;
+      if (NULL == (sym = strdup (sym_name)))
+       {
+         LOG_STRERROR ("strdup");
+         closedir (dir);
+         return;
+       }
+      if (NULL != (dot = strchr (sym, '.')))
+       *dot = '\0';
+      dlc->res = EXTRACTOR_plugin_add (dlc->res,
+                                      sym,
+                                      NULL,
+                                      dlc->flags);
+      free (sym);
+    }
+  closedir (dir);
+}
+
+
+/**
+ * Load the default set of plugins. The default can be changed
+ * by setting the LIBEXTRACTOR_LIBRARIES environment variable.
+ * If it is set to "env", then this function will return
+ * EXTRACTOR_plugin_add_config (NULL, env, flags).  Otherwise,
+ * it will load all of the installed plugins and return them.
+ *
+ * @param flags options for all of the plugins loaded
+ * @return the default set of plugins, NULL if no plugins were found
+ */
+struct EXTRACTOR_PluginList * 
+EXTRACTOR_plugin_add_defaults (enum EXTRACTOR_Options flags)
+{
+  struct DefaultLoaderContext dlc;
+  char *env;
+
+  env = getenv ("LIBEXTRACTOR_LIBRARIES");
+  if (NULL != env)
+    return EXTRACTOR_plugin_add_config (NULL, env, flags);
+  dlc.res = NULL;
+  dlc.flags = flags;
+  get_installation_paths (&load_plugins_from_dir,
+                         &dlc);
+  return dlc.res;
+}
+
+
+/* end of extractor_plugpath.c */