Fix SANE_CONFIG_DIR handling, use it for dll.d/; Add sanei_config_get_paths

* include/sane/sanei_config.h sanei/sanei_config.c: Add function
        sanei_config_get_paths to obtain all configuration pathes (from env var
        SANE_CONFIG_DIR and default paths); fix pointers to invalid/freed
        strings when SANE_CONFIG_DIR is set

* backend/dll.c: When searching for the dll.d/ directory, also use
        the SANE_CONFIG_DIR env variable.

ChangeLog

@@ -1,3 +1,11 @@
+2010-09-18 Reinhold Kainhofer <reinhold@kainhofer.com>
+	* include/sane/sanei_config.h sanei/sanei_config.c: Add
+	function sanei_config_get_paths to obtain all configuration pathes
+	(from env var SANE_CONFIG_DIR and default paths); fix pointers to
+	invalid/freed strings when SANE_CONFIG_DIR is set.
+	* backend/dll.c: When searching for the dll.d/ directory,
+	also use the SANE_CONFIG_DIR env variable.
+
 2010-07-12 Julien Blache <jb@jblache.org>
 	* doc/descriptions-external/epkowa.desc: update for iScan 2.26.0,
 	from Alesh Slovak <alesh.slovak@avasys.jp>.

backend/dll.c

@@ -44,7 +44,7 @@
 
 /* Please increase version number with every change 
    (don't forget to update dll.desc) */
-#define DLL_VERSION "1.0.12"
+#define DLL_VERSION "1.0.13"
 
 #ifdef _AIX
 # include "lalloca.h"		/* MUST come first for AIX! */
@@ -773,14 +773,37 @@ read_dlld (void)
   DIR *dlld;
   struct dirent *dllconf;
   struct stat st;
-  char conffile[PATH_MAX];
+  char conffile[PATH_MAX], dlldir[PATH_MAX];
   size_t len, plen;
+  const char *dir_list;
+  char *copy, *next, *dir;
 
-  DBG (5, "sane_init/read_dlld: processing %s ...\n",
-       STRINGIFY(PATH_SANE_CONFIG_DIR) "/dll.d");
+  dir_list = sanei_config_get_paths ();
+  if (!dir_list)
+    {
+      DBG(2, "sane_init/read_dlld: Unable to detect configuration directories\n");
+      return;
+    }
 
-  /* Read files under $sysconfdir/sane.d/dll.d */
-  dlld = opendir (STRINGIFY(PATH_SANE_CONFIG_DIR) "/dll.d");
+  copy = strdup (dir_list);
+
+  for (next = copy; (dir = strsep (&next, DIR_SEP)) != NULL;)
+    {
+      snprintf (dlldir, sizeof (dlldir), "%s%s", dir, "/dll.d");
+
+      DBG(4, "sane_init/read_dlld: attempting to open directory `%s'\n", dlldir);
+
+      dlld = opendir (dlldir);
+      if (dlld)
+	{
+	  /* length of path to parent dir of dll.d/ */
+	  plen = strlen (dir) + 1;
+
+	  DBG(3, "sane_init/read_dlld: using config directory `%s'\n", dlldir);
+	  break;
+	}
+    }
+  free (copy);
 
   if (dlld == NULL)
     {
@@ -789,8 +812,6 @@ read_dlld (void)
       return;
     }
 
-  plen = strlen (STRINGIFY(PATH_SANE_CONFIG_DIR)) + 1;
-
   while ((dllconf = readdir (dlld)) != NULL)
     {
       /* dotfile (or directory) */
@@ -804,8 +825,7 @@ read_dlld (void)
           || (dllconf->d_name[len-1] == '#'))
         continue;
 
-      snprintf (conffile, PATH_MAX, "%s/dll.d/%s",
-                STRINGIFY (PATH_SANE_CONFIG_DIR), dllconf->d_name);
+      snprintf (conffile, PATH_MAX, "%s/%s", dlldir, dllconf->d_name);
 
       DBG (5, "sane_init/read_dlld: considering %s\n", conffile);
 

doc/descriptions/dll.desc

@@ -1,5 +1,5 @@
 :backend "dll"               ; name of backend
-:version "1.0.12"
+:version "1.0.13"
 :manpage "sane-dll"
 :url "mailto:henning@meier-geinitz.de"
 

include/sane/sanei_config.h

@@ -164,4 +164,12 @@ extern SANE_Status sanei_configure_attach (
   SANEI_Config *config,
   SANE_Status (*config_attach)(SANEI_Config *config, const char *devname)
 );
+
+/** Return the list of config directories, extracted from the SANE_CONFIG_DIR
+ * environment variable and the default paths.
+ * @return a string containing the configuration paths, separated by the
+ *         operating system's path separator
+ */
+extern const char *sanei_config_get_paths (void);
+
 #endif	/* sanei_config_h */

sanei/sanei_config.c

@@ -76,21 +76,25 @@
 #include <FindDirectory.h>
 #endif
 
-static const char *dir_list;
+static char *dir_list;
 
-FILE *
-sanei_config_open (const char *filename)
+const char *
+sanei_config_get_paths ()
 {
-  char *copy, *next, *dir, result[PATH_MAX];
-  FILE *fp = 0;
+#ifdef __BEOS__
+  char result[PATH_MAX];
+#endif
+  void *mem;
+  char *dlist;
   size_t len;
-  void *mem = 0;
 
   if (!dir_list)
     {
       DBG_INIT();
 
-      dir_list = getenv ("SANE_CONFIG_DIR");
+      dlist = getenv ("SANE_CONFIG_DIR");
+      if (dlist)
+	dir_list = strdup (dlist);
 #ifdef __BEOS__
       /* ~/config/settings/SANE takes precedence over /etc/sane.d/ */
       if (!dir_list)
@@ -99,7 +103,7 @@ sanei_config_open (const char *filename)
 	    {
 	      strcat(result,"/SANE");
 	      strcat(result,DIR_SEP); /* do append the default ones */
-	      dir_list = result;
+	      dir_list = strdup (result);
 	    }
 	}
 #endif
@@ -110,20 +114,39 @@ sanei_config_open (const char *filename)
 	    {
 	      /* append default search directories: */
 	      mem = malloc (len + sizeof (DEFAULT_DIRS));
-
 	      memcpy (mem, dir_list, len);
 	      memcpy ((char *) mem + len, DEFAULT_DIRS, sizeof (DEFAULT_DIRS));
+	      free (dir_list);
 	      dir_list = mem;
 	    }
 	}
       else
-	dir_list = DEFAULT_DIRS;
+	{
+	  /* Create a copy, since we might call free on it */
+	  dir_list = strdup (DEFAULT_DIRS);
+	}
+    }
+  DBG (5, "sanei_config_get_paths: using config directories  %s\n", dir_list);
+
+  return dir_list;
+}
+
+FILE *
+sanei_config_open (const char *filename)
+{
+  char *next, *dir, result[PATH_MAX];
+  const char *cfg_dir_list;
+  FILE *fp;
+  char *copy;
+
+  cfg_dir_list = sanei_config_get_paths ();
+  if (!cfg_dir_list)
+    {
+      DBG(2, "sanei_config_open: could not find config file `%s'\n", filename);
+      return NULL;
     }
 
-  copy = strdup (dir_list);
-
-  if (mem)
-    free(mem);
+  copy = strdup (cfg_dir_list);
 
   for (next = copy; (dir = strsep (&next, DIR_SEP)) != 0; )
     {