Get rid of small memory leak when using 'scanimage -L'.

backend/dll.c

@@ -178,6 +178,13 @@ struct alias
     char *newname;
   };
 
+/*
+ * List of available devices, allocated by sane_get_devices, released
+ * by sane_exit()
+ */
+static const SANE_Device **devlist = NULL;
+static int devlist_size = 0, devlist_len = 0;
+
 static struct alias *first_alias;
 static SANE_Auth_Callback auth_callback;
 static struct backend *first_backend;
@@ -584,6 +591,18 @@ sane_exit (void)
       free(alias->oldname);
       free(alias);
     }
+
+  if (NULL != devlist)
+    { /* Release memory allocated by sane_get_devices(). */
+      int i = 0;
+      while (devlist[i])
+        free(devlist[i++]);
+      free(devlist);
+
+      devlist = NULL;
+      devlist_size = 0;
+      devlist_len = 0;
+    }
 }
 
 /* Note that a call to get_devices() implies that we'll have to load
@@ -594,8 +613,6 @@ sane_exit (void)
 SANE_Status
 sane_get_devices (const SANE_Device *** device_list, SANE_Bool local_only)
 {
-  static int devlist_size = 0, devlist_len = 0;
-  static const SANE_Device **devlist;
   const SANE_Device **be_list;
   struct backend *be;
   SANE_Status status;

backend/v4l.c

@@ -108,6 +108,7 @@
 #include "sane/sanei_config.h"
 #define V4L_CONFIG_FILE "v4l.conf"
 
+static const SANE_Device ** devlist = NULL;
 static int num_devices;
 static V4L_Device * first_dev;
 static V4L_Scanner * first_handle;
@@ -179,6 +180,9 @@ attach (const char *devname, V4L_Device **devp)
 {
   V4L_Device * q;
 
+  if (!devp)
+    return SANE_STATUS_INVAL;
+
   errno = 0;
 
   q = malloc (sizeof (*q));
@@ -199,12 +203,8 @@ attach (const char *devname, V4L_Device **devp)
   first_dev = q;
 
 
-  if (devp)
-    *devp = q;
+  *devp = q;
   return SANE_STATUS_GOOD;
-
-  free (q);
-  return SANE_STATUS_INVAL;
 }
 
 
@@ -626,12 +626,17 @@ sane_exit (void)
       free ((void *) dev->sane.name);
       free (dev);
     }
+
+  if (NULL != devlist)
+    {
+      free(devlist);
+      devlist = NULL;
+    }
 }
 
 SANE_Status
 sane_get_devices (const SANE_Device *** device_list, SANE_Bool local_only)
 {
-  static const SANE_Device ** devlist = 0;
   V4L_Device *dev;
   int i;