Clean up on exit, and convert to singly-linked-lists

This adds fp_exit() to the public API, intended to be called while the
driving app is shutting down.

TODO

@@ -4,8 +4,6 @@ identification
 test suite against NFIQ compliance set
 make library optionally asynchronous and maybe thread-safe
 nbis cleanups
-track open devices, so we can close them during libfprint close
-free memory during libfprint close
 API function to determine if img device supports uncond. capture
 race-free way of saying "save this print but don't overwrite"
 

examples/enroll.c

@@ -92,7 +92,7 @@ struct fp_print_data *enroll(struct fp_dev *dev) {
 
 int main(void)
 {
-	int r;
+	int r = 1;
 	struct fp_dscv_dev *ddev;
 	struct fp_dscv_dev **discovered_devs;
 	struct fp_dev *dev;
@@ -113,20 +113,20 @@ int main(void)
 	discovered_devs = fp_discover_devs();
 	if (!discovered_devs) {
 		fprintf(stderr, "Could not discover devices\n");
-		exit(1);
+		goto out;
 	}
 
 	ddev = discover_device(discovered_devs);
 	if (!ddev) {
 		fprintf(stderr, "No devices detected.\n");
-		exit(1);
+		goto out;
 	}
 
 	dev = fp_dev_open(ddev);
 	fp_dscv_devs_free(discovered_devs);
 	if (!dev) {
 		fprintf(stderr, "Could not open device.\n");
-		exit(1);
+		goto out;
 	}
 
 	printf("Opened device. It's now time to enroll your finger.\n\n");
@@ -141,6 +141,8 @@ int main(void)
 	fp_print_data_free(data);
 out_close:
 	fp_dev_close(dev);
+out:
+	fp_exit();
 	return r;
 }
 

examples/img_capture.c

@@ -54,20 +54,20 @@ int main(void)
 	discovered_devs = fp_discover_devs();
 	if (!discovered_devs) {
 		fprintf(stderr, "Could not discover devices\n");
-		exit(1);
+		goto out;
 	}
 
 	ddev = discover_device(discovered_devs);
 	if (!ddev) {
 		fprintf(stderr, "No devices detected.\n");
-		exit(1);
+		goto out;
 	}
 
 	dev = fp_dev_open(ddev);
 	fp_dscv_devs_free(discovered_devs);
 	if (!dev) {
 		fprintf(stderr, "Could not open device.\n");
-		exit(1);
+		goto out;
 	}
 
 	if (!fp_dev_supports_imaging(dev)) {
@@ -100,6 +100,8 @@ int main(void)
 	r = 0;
 out_close:
 	fp_dev_close(dev);
+out:
+	fp_exit();
 	return r;
 }
 

examples/img_capture_continuous.c

@@ -153,25 +153,25 @@ int main(void)
 	discovered_devs = fp_discover_devs();
 	if (!discovered_devs) {
 		fprintf(stderr, "Could not discover devices\n");
-		exit(1);
+		goto out;
 	}
 
 	ddev = discover_device(discovered_devs);
 	if (!ddev) {
 		fprintf(stderr, "No devices detected.\n");
-		exit(1);
+		goto out;
 	}
 
 	dev = fp_dev_open(ddev);
 	fp_dscv_devs_free(discovered_devs);
 	if (!dev) {
 		fprintf(stderr, "Could not open device.\n");
-		exit(1);
+		goto out;
 	}
 
 	if (!fp_dev_supports_imaging(dev)) {
 		fprintf(stderr, "this device does not have imaging capabilities.\n");
-		goto out;
+		goto out_close;
 	}
 
 	img_width = fp_dev_get_img_width(dev);
@@ -179,24 +179,24 @@ int main(void)
 	if (img_width <= 0 || img_height <= 0) {
 		fprintf(stderr, "this device returns images with variable dimensions,"
 			" this example does not support that.\n");
-		goto out;
+		goto out_close;
 	}
 	framebuffer = malloc(img_width * img_height * 2);
 	if (!framebuffer)
-		goto out;
+		goto out_close;
 
 	/* make the window */
 	display = XOpenDisplay(getenv("DISPLAY"));
 	if(display == NULL) {
 		fprintf(stderr,"Could not open display \"%s\"\n",
 				getenv("DISPLAY"));
-		goto out;
+		goto out_close;
 	}
 
 	QueryXv();
 
 	if (adaptor < 0)
-		goto out;
+		goto out_close;
 
 	window = XCreateSimpleWindow(display, DefaultRootWindow(display), 0, 0,
 			img_width, img_height, 0,
@@ -216,7 +216,7 @@ int main(void)
 		r = fp_dev_img_capture(dev, 1, &img);
 		if (r) {
 			fprintf(stderr, "image capture failed, code %d\n", r);
-			goto out;
+			goto out_close;
 		}
 		if (standardize)
 			fp_img_standardize(img);
@@ -234,7 +234,7 @@ int main(void)
 			case XK_q:
 			case XK_Q:
 				r = 0;
-				goto out;
+				goto out_close;
 				break;
 			case XK_s:
 			case XK_S:
@@ -245,7 +245,7 @@ int main(void)
 	}
 
 	r = 0;
-out:
+out_close:
 	if (framebuffer)
 		free(framebuffer);
 	fp_dev_close(dev);
@@ -253,6 +253,8 @@ out:
 		XUnmapWindow(display, window);
 	if (display != NULL)
 		XFlush(display);
+out:
+	fp_exit();
 	return r;
 }
 

examples/verify.c

@@ -76,7 +76,7 @@ int verify(struct fp_dev *dev, struct fp_print_data *data)
 
 int main(void)
 {
-	int r;
+	int r = 1;
 	struct fp_dscv_dev *ddev;
 	struct fp_dscv_dev **discovered_devs;
 	struct fp_dev *dev;
@@ -91,20 +91,20 @@ int main(void)
 	discovered_devs = fp_discover_devs();
 	if (!discovered_devs) {
 		fprintf(stderr, "Could not discover devices\n");
-		exit(1);
+		goto out;
 	}
 
 	ddev = discover_device(discovered_devs);
 	if (!ddev) {
 		fprintf(stderr, "No devices detected.\n");
-		exit(1);
+		goto out;
 	}
 
 	dev = fp_dev_open(ddev);
 	fp_dscv_devs_free(discovered_devs);
 	if (!dev) {
 		fprintf(stderr, "Could not open device.\n");
-		exit(1);
+		goto out;
 	}
 
 	printf("Opened device. Loading previously enrolled right index finger "
@@ -132,6 +132,8 @@ int main(void)
 	fp_print_data_free(data);
 out_close:
 	fp_dev_close(dev);
+out:
+	fp_exit();
 	return r;
 }
 

examples/verify_live.c

@@ -126,7 +126,7 @@ int verify(struct fp_dev *dev, struct fp_print_data *data)
 
 int main(void)
 {
-	int r;
+	int r = 1;
 	struct fp_dscv_dev *ddev;
 	struct fp_dscv_dev **discovered_devs;
 	struct fp_dev *dev;
@@ -141,20 +141,20 @@ int main(void)
 	discovered_devs = fp_discover_devs();
 	if (!discovered_devs) {
 		fprintf(stderr, "Could not discover devices\n");
-		exit(1);
+		goto out;
 	}
 
 	ddev = discover_device(discovered_devs);
 	if (!ddev) {
 		fprintf(stderr, "No devices detected.\n");
-		exit(1);
+		goto out;
 	}
 
 	dev = fp_dev_open(ddev);
 	fp_dscv_devs_free(discovered_devs);
 	if (!dev) {
 		fprintf(stderr, "Could not open device.\n");
-		exit(1);
+		goto out;
 	}
 
 	printf("Opened device. It's now time to enroll your finger.\n\n");
@@ -181,6 +181,8 @@ int main(void)
 	fp_print_data_free(data);
 out_close:
 	fp_dev_close(dev);
+out:
+	fp_exit();
 	return r;
 }
 

libfprint/core.c

@@ -276,7 +276,8 @@
  * circumstances, you don't have to worry about driver IDs at all.
  */
 
-static GList *registered_drivers = NULL;
+static GSList *registered_drivers = NULL;
+static GSList *opened_devices = NULL;
 
 void fpi_log(enum fpi_log_level level, const char *component,
 	const char *function, const char *format, ...)
@@ -323,7 +324,7 @@ static void register_driver(struct fp_driver *drv)
 		fp_err("not registering driver %s: driver ID is 0");
 		return;
 	}
-	registered_drivers = g_list_prepend(registered_drivers, (gpointer) drv);
+	registered_drivers = g_slist_prepend(registered_drivers, (gpointer) drv);
 	fp_dbg("registered driver %s", drv->name);
 }
 
@@ -353,7 +354,7 @@ static void register_drivers(void)
 static struct fp_driver *find_supporting_driver(struct usb_device *udev,
 	const struct usb_id **usb_id)
 {
-	GList *elem = registered_drivers;
+	GSList *elem = registered_drivers;
 	
 	do {
 		struct fp_driver *drv = elem->data;
@@ -367,7 +368,7 @@ static struct fp_driver *find_supporting_driver(struct usb_device *udev,
 				*usb_id = id;
 				return drv;
 			}
-	} while (elem = g_list_next(elem));
+	} while (elem = g_slist_next(elem));
 	return NULL;
 }
 
@@ -405,7 +406,7 @@ static struct fp_dscv_dev *discover_dev(struct usb_device *udev)
  */
 API_EXPORTED struct fp_dscv_dev **fp_discover_devs(void)
 {
-	GList *tmplist = NULL;
+	GSList *tmplist = NULL;
 	struct fp_dscv_dev **list;
 	struct usb_device *udev;
 	struct usb_bus *bus;
@@ -418,7 +419,7 @@ API_EXPORTED struct fp_dscv_dev **fp_discover_devs(void)
 	usb_find_devices();
 
 	/* Check each device against each driver, temporarily storing successfully
-	 * discovered devices in a GList.
+	 * discovered devices in a GSList.
 	 *
 	 * Quite inefficient but excusable as we'll only be dealing with small
 	 * sets of drivers against small sets of USB devices */
@@ -427,23 +428,23 @@ API_EXPORTED struct fp_dscv_dev **fp_discover_devs(void)
 			struct fp_dscv_dev *ddev = discover_dev(udev);
 			if (!ddev)
 				continue;
-			tmplist = g_list_prepend(tmplist, (gpointer) ddev);
+			tmplist = g_slist_prepend(tmplist, (gpointer) ddev);
 			dscv_count++;
 		}
 
-	/* Convert our temporary GList into a standard NULL-terminated pointer
+	/* Convert our temporary GSList into a standard NULL-terminated pointer
 	 * array. */
 	list = g_malloc(sizeof(*list) * (dscv_count + 1));
 	if (dscv_count > 0) {
-		GList *elem = tmplist;
+		GSList *elem = tmplist;
 		int i = 0;
 		do {
 			list[i++] = elem->data;
-		} while (elem = g_list_next(elem));
+		} while (elem = g_slist_next(elem));
 	}
 	list[dscv_count] = NULL; /* NULL-terminate */
 
-	g_list_free(tmplist);
+	g_slist_free(tmplist);
 	return list;
 }
 
@@ -601,9 +602,19 @@ API_EXPORTED struct fp_dev *fp_dev_open(struct fp_dscv_dev *ddev)
 	}
 
 	fp_dbg("");
+	opened_devices = g_slist_prepend(opened_devices, (gpointer) dev);
 	return dev;
 }
 
+/* performs close operation without modifying opened_devices list */
+static void do_close(struct fp_dev *dev)
+{
+	if (dev->drv->exit)
+		dev->drv->exit(dev);
+	usb_close(dev->udev);
+	g_free(dev);
+}
+
 /** \ingroup dev
  * Close a device. You must call this function when you are finished using
  * a fingerprint device.
@@ -612,10 +623,11 @@ API_EXPORTED struct fp_dev *fp_dev_open(struct fp_dscv_dev *ddev)
 API_EXPORTED void fp_dev_close(struct fp_dev *dev)
 {
 	fp_dbg("");
-	if (dev->drv->exit)
-		dev->drv->exit(dev);
-	usb_close(dev->udev);
-	g_free(dev);
+
+	if (g_slist_index(opened_devices, (gconstpointer) dev) == -1)
+		fp_err("device %p not in opened list!", dev);
+	opened_devices = g_slist_remove(opened_devices, (gconstpointer) dev);
+	do_close(dev);
 }
 
 /** \ingroup dev
@@ -986,3 +998,27 @@ API_EXPORTED int fp_init(void)
 	return 0;
 }
 
+/** \ingroup core
+ * Deinitialise libfprint. This function should be called during your program
+ * exit sequence. You must not use any libfprint functions after calling this
+ * function, unless you call fp_init() again.
+ */
+API_EXPORTED void fp_exit(void)
+{
+	GSList *elem = opened_devices;
+	fp_dbg("");
+
+	if (elem != NULL) {
+		do {
+			fp_dbg("naughty app left a device open on exit!");
+			do_close((struct fp_dev *) elem->data);
+		} while (elem = g_slist_next(elem));
+		g_slist_free(opened_devices);
+		opened_devices = NULL;
+	}
+
+	fpi_data_exit();
+	g_slist_free(registered_drivers);
+	registered_drivers = NULL;
+}
+

libfprint/data.c

@@ -45,7 +45,6 @@
  * in any fashion that suits you.
  */
 
-/* FIXME: should free this during library shutdown */
 static char *base_store = NULL;
 
 static void storage_setup(void)
@@ -63,6 +62,11 @@ static void storage_setup(void)
 	/* FIXME handle failure */
 }
 
+void fpi_data_exit(void)
+{
+	g_free(base_store);
+}
+
 #define FP_FINGER_IS_VALID(finger) \
 	((finger) >= LEFT_THUMB && (finger) <= RIGHT_LITTLE)
 

libfprint/fp_internal.h

@@ -182,6 +182,7 @@ struct fpi_print_data_fp1 {
 	unsigned char data[0];
 } __attribute__((__packed__));
 
+void fpi_data_exit(void);
 struct fp_print_data *fpi_print_data_new(struct fp_dev *dev, size_t length);
 gboolean fpi_print_data_compatible(uint16_t driver_id1, uint32_t devtype1,
 	enum fp_print_data_type type1, uint16_t driver_id2, uint32_t devtype2,

libfprint/fprint.h

@@ -183,6 +183,7 @@ void fp_img_free(struct fp_img *img);
 
 /* Library */
 int fp_init(void);
+void fp_exit(void);
 
 #endif