Print discovery

Add concept of "discovered prints" and flesh out the API. A discovered print
was found based on file name but has not been checked for file integrity,
and of course there is no guarantee that it is usable when you try to
use it later (might have been deleted, etc).

The .fprint directory structure was changed - instead of using mnemonics
like "rind" we use their numeric value in the fp_finger enum as the filename.

libfprint/data.c

@@ -48,38 +48,29 @@ static void storage_setup(void)
 	/* FIXME handle failure */
 }
 
-static const char *finger_code_to_str(enum fp_finger finger)
+#define FP_FINGER_IS_VALID(finger) \
+	((finger) >= LEFT_THUMB && (finger) <= RIGHT_LITTLE)
+
+/* for debug messages only */
+static const char *finger_num_to_str(enum fp_finger finger)
 {
 	const char *names[] = {
-		[LEFT_THUMB] = "lthu",
-		[LEFT_INDEX] = "lind",
-		[LEFT_MIDDLE] = "lmid",
-		[LEFT_RING] = "lrin",
-		[LEFT_LITTLE] = "llit",
-		[RIGHT_THUMB] = "rthu",
-		[RIGHT_INDEX] = "rind",
-		[RIGHT_MIDDLE] = "rmid",
-		[RIGHT_RING] = "rrin",
-		[RIGHT_LITTLE] = "rlit",
+		[LEFT_THUMB] = "left thumb",
+		[LEFT_INDEX] = "left index",
+		[LEFT_MIDDLE] = "left middle",
+		[LEFT_RING] = "left ring",
+		[LEFT_LITTLE] = "left little",
+		[RIGHT_THUMB] = "right thumb",
+		[RIGHT_INDEX] = "right index",
+		[RIGHT_MIDDLE] = "right middle",
+		[RIGHT_RING] = "right ring",
+		[RIGHT_LITTLE] = "right little",
 	};
-	if (finger < LEFT_THUMB || finger > RIGHT_LITTLE)
-		return NULL;
+	if (!FP_FINGER_IS_VALID(finger))
+		return "UNKNOWN";
 	return names[finger];
 }
 
-static enum fp_print_data_type get_data_type_for_dev(struct fp_dev *dev)
-{
-	switch (dev->drv->type) {
-	case DRIVER_PRIMITIVE:
-		return PRINT_DATA_RAW;
-	case DRIVER_IMAGING:
-		return PRINT_DATA_NBIS_MINUTIAE;
-	default:
-		fp_err("unrecognised drv type %d", dev->drv->type);
-		return PRINT_DATA_RAW;
-	}
-}
-
 static struct fp_print_data *print_data_new(uint16_t driver_id,
 	uint32_t devtype, enum fp_print_data_type type, size_t length)
 {
@@ -98,7 +89,7 @@ struct fp_print_data *fpi_print_data_new(struct fp_dev *dev, size_t length)
 	struct fp_print_data *data = g_malloc(sizeof(*data) + length);
 	memset(data, 0, sizeof(*data));
 	return print_data_new(dev->drv->id, dev->devtype,
-		get_data_type_for_dev(dev), length);
+		fpi_driver_get_data_type(dev->drv), length);
 }
 
 API_EXPORTED size_t fp_print_data_get_data(struct fp_print_data *data,
@@ -148,7 +139,7 @@ API_EXPORTED struct fp_print_data *fp_print_data_from_data(unsigned char *buf,
 	return data;
 }
 
-static char *__get_path_to_storedir(uint16_t driver_id, uint32_t devtype)
+static char *get_path_to_storedir(uint16_t driver_id, uint32_t devtype)
 {
 	char idstr[5];
 	char devtypestr[9];
@@ -159,53 +150,55 @@ static char *__get_path_to_storedir(uint16_t driver_id, uint32_t devtype)
 	return g_build_filename(base_store, idstr, devtypestr, NULL);
 }
 
-static char *get_path_to_storedir(struct fp_dev *dev)
-{
-	return __get_path_to_storedir(dev->drv->id, dev->devtype);
-}
-
-static char *get_path_to_print(struct fp_dev *dev, const char *fingerstr)
+static char *__get_path_to_print(uint16_t driver_id, uint32_t devtype,
+	enum fp_finger finger)
 {
 	char *dirpath;
 	char *path;
+	char fingername[2];
 
-	dirpath = get_path_to_storedir(dev);
-	path = g_build_filename(dirpath, fingerstr, NULL);
+	g_snprintf(fingername, 2, "%x", finger);
+
+	dirpath = get_path_to_storedir(driver_id, devtype);
+	path = g_build_filename(dirpath, fingername, NULL);
 	g_free(dirpath);
 	return path;
 }
 
+static char *get_path_to_print(struct fp_dev *dev, enum fp_finger finger)
+{
+	return __get_path_to_print(dev->drv->id, dev->devtype, finger);
+}
+
 API_EXPORTED int fp_print_data_save(struct fp_print_data *data,
 	enum fp_finger finger)
 {
 	GError *err = NULL;
 	char *path;
 	char *dirpath;
-	const char *fingerstr = finger_code_to_str(finger);
 	unsigned char *buf;
 	size_t len;
 	int r;
 
-	if (!fingerstr)
-		return -EINVAL;
-
 	if (!base_store)
 		storage_setup();
 
-	fp_dbg("save %s print from driver %04x", fingerstr, data->driver_id);
+	fp_dbg("save %s print from driver %04x", finger_num_to_str(finger),
+		data->driver_id);
 	len = fp_print_data_get_data(data, &buf);
 	if (!len)
 		return -ENOMEM;
 
-	dirpath = __get_path_to_storedir(data->driver_id, data->devtype);
+	path = __get_path_to_print(data->driver_id, data->devtype, finger);
+	dirpath = g_path_get_dirname(path);
 	r = g_mkdir_with_parents(dirpath, DIR_PERMS);
 	if (r < 0) {
 		fp_err("couldn't create storage directory");
+		g_free(path);
 		g_free(dirpath);
 		return r;
 	}
 
-	path = g_build_filename(dirpath, fingerstr, NULL);
 	fp_dbg("saving to %s", path);
 	g_file_set_contents(path, buf, len, &err);
 	free(buf);
@@ -213,7 +206,7 @@ API_EXPORTED int fp_print_data_save(struct fp_print_data *data,
 	g_free(path);
 	if (err) {
 		r = err->code;
-		fp_err("%s save failed: %s", fingerstr, err->message);
+		fp_err("save failed: %s", err->message);
 		g_error_free(err);
 		/* FIXME interpret error codes */
 		return r;
@@ -222,65 +215,39 @@ API_EXPORTED int fp_print_data_save(struct fp_print_data *data,
 	return 0;
 }
 
-gboolean fpi_print_data_compatible(struct fp_print_data *data,
-	struct fp_dev *dev)
+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,
+	enum fp_print_data_type type2)
 {
-	struct fp_driver *drv = dev->drv;
-
-	if (drv->id != data->driver_id) {
-		fp_dbg("driver name mismatch: %02x vs %02x", drv->id, data->driver_id);
+	if (driver_id1 != driver_id2) {
+		fp_dbg("driver ID mismatch: %02x vs %02x", driver_id1, driver_id2);
 		return FALSE;
 	}
 
-	if (dev->devtype != data->devtype) {
-		fp_dbg("devtype mismatch: %04x vs %04x", dev->devtype, data->devtype);
+	if (devtype1 != devtype2) {
+		fp_dbg("devtype mismatch: %04x vs %04x", devtype1, devtype2);
 		return FALSE;
 	}
 
-	switch (data->type) {
-	case PRINT_DATA_RAW:
-		if (drv->type != DRIVER_PRIMITIVE) {
-			fp_dbg("raw data vs primitive driver mismatch");
-			return FALSE;
-		}
-		break;
-	case PRINT_DATA_NBIS_MINUTIAE:
-		if (drv->type != DRIVER_IMAGING) {
-			fp_dbg("minutiae data vs imaging driver mismatch");
-			return FALSE;
-		}
-		break;
-	default:
-		fp_err("unrecognised data type %d", data->type);
+	if (type1 != type2) {
+		fp_dbg("type mismatch: %d vs %d", type1, type2);
 		return FALSE;
 	}
 
 	return TRUE;
 }
 
-API_EXPORTED int fp_print_data_load(struct fp_dev *dev,
-	enum fp_finger finger, struct fp_print_data **data)
+static int load_from_file(char *path, struct fp_print_data **data)
 {
-	const char *fingerstr = finger_code_to_str(finger);
-	gchar *path;
 	gsize length;
 	gchar *contents;
 	GError *err = NULL;
-	struct fp_print_data *fdata;
 
-	if (!fingerstr)
-		return -EINVAL;
-
-	if (!base_store)
-		storage_setup();
-
-	path = get_path_to_print(dev, fingerstr);
 	fp_dbg("from %s", path);
 	g_file_get_contents(path, &contents, &length, &err);
-	g_free(path);
 	if (err) {
 		int r = err->code;
-		fp_err("%s load failed: %s", fingerstr, err->message);
+		fp_err("%s load failed: %s", path, err->message);
 		g_error_free(err);
 		/* FIXME interpret more error codes */
 		if (r == G_FILE_ERROR_NOENT)
@@ -289,11 +256,30 @@ API_EXPORTED int fp_print_data_load(struct fp_dev *dev,
 			return r;
 	}
 
-	fdata = fp_print_data_from_data(contents, length);
+	*data = fp_print_data_from_data(contents, length);
 	g_free(contents);
+	return 0;
+}
 
-	if (!fpi_print_data_compatible(fdata, dev)) {
+API_EXPORTED int fp_print_data_load(struct fp_dev *dev,
+	enum fp_finger finger, struct fp_print_data **data)
+{
+	gchar *path;
+	struct fp_print_data *fdata;
+	int r;
+
+	if (!base_store)
+		storage_setup();
+
+	path = get_path_to_print(dev, finger);
+	r = load_from_file(path, &fdata);
+	g_free(path);
+	if (r)
+		return r;
+
+	if (!fp_dev_supports_print_data(dev, fdata)) {
 		fp_err("print data is not compatible!");
+		fp_print_data_free(fdata);
 		return -EINVAL;
 	}
 
@@ -301,6 +287,12 @@ API_EXPORTED int fp_print_data_load(struct fp_dev *dev,
 	return 0;
 }
 
+API_EXPORTED int fp_print_data_from_dscv_print(struct fp_dscv_print *print,
+	struct fp_print_data **data)
+{
+	return load_from_file(print->path, data);
+}
+
 API_EXPORTED void fp_print_data_free(struct fp_print_data *data)
 {
 	g_free(data);
@@ -315,3 +307,170 @@ API_EXPORTED uint32_t fp_print_data_get_devtype(struct fp_print_data *data)
 {
 	return data->devtype;
 }
+
+static GSList *scan_dev_store_dir(char *devpath, uint16_t driver_id,
+	uint32_t devtype, GSList *list)
+{
+	GError *err = NULL;
+	const gchar *ent;
+	struct fp_dscv_print *print;
+
+	GDir *dir = g_dir_open(devpath, 0, &err);
+	if (!dir) {
+		fp_err("opendir %s failed: %s", devpath, err->message);
+		g_error_free(err);
+		return list;
+	}
+
+	while (ent = g_dir_read_name(dir)) {
+		/* ent is an 1 hex character fp_finger code */
+		guint64 val;
+		enum fp_finger finger;
+		gchar *endptr;
+
+		if (*ent == 0 || strlen(ent) != 1)
+			continue;
+
+		val = g_ascii_strtoull(ent, &endptr, 16);
+		if (endptr == ent || !FP_FINGER_IS_VALID(val)) {
+			fp_dbg("skipping print file %s", ent);
+			continue;
+		}
+
+		finger = (enum fp_finger) val;
+		print = g_malloc(sizeof(*print));
+		print->driver_id = driver_id;
+		print->devtype = devtype;
+		print->path = g_build_filename(devpath, ent, NULL);
+		print->finger = finger;
+		list = g_slist_prepend(list, print);
+	}
+
+	g_dir_close(dir);
+	return list;
+}
+
+static GSList *scan_driver_store_dir(char *drvpath, uint16_t driver_id,
+	GSList *list)
+{
+	GError *err = NULL;
+	const gchar *ent;
+
+	GDir *dir = g_dir_open(drvpath, 0, &err);
+	if (!dir) {
+		fp_err("opendir %s failed: %s", drvpath, err->message);
+		g_error_free(err);
+		return list;
+	}
+
+	while (ent = g_dir_read_name(dir)) {
+		/* ent is an 8 hex character devtype */
+		guint64 val;
+		uint32_t devtype;
+		gchar *endptr;
+		gchar *path;
+
+		if (*ent == 0 || strlen(ent) != 8)
+			continue;
+
+		val = g_ascii_strtoull(ent, &endptr, 16);
+		if (endptr == ent) {
+			fp_dbg("skipping devtype %s", ent);
+			continue;
+		}
+
+		devtype = (uint32_t) val;
+		path = g_build_filename(drvpath, ent, NULL);
+		list = scan_dev_store_dir(path, driver_id, devtype, list);
+		g_free(path);
+	}
+
+	g_dir_close(dir);
+	return list;
+}
+
+API_EXPORTED struct fp_dscv_print **fp_discover_prints(void)
+{
+	GDir *dir;
+	const gchar *ent;
+	GError *err = NULL;
+	GSList *tmplist = NULL;
+	GSList *elem;
+	unsigned int tmplist_len;
+	struct fp_dscv_print **list;
+	unsigned int i;
+
+	if (!base_store)
+		storage_setup();
+
+	dir = g_dir_open(base_store, 0, &err);
+	if (!dir) {
+		fp_err("opendir %s failed: %s", base_store, err->message);
+		g_error_free(err);
+		return NULL;
+	}
+
+	while (ent = g_dir_read_name(dir)) {
+		/* ent is a 4 hex digit driver_id */
+		gchar *endptr;
+		gchar *path;
+		guint64 val;
+		uint16_t driver_id;
+
+		if (*ent == 0 || strlen(ent) != 4)
+			continue;
+
+		val = g_ascii_strtoull(ent, &endptr, 16);
+		if (endptr == ent) {
+			fp_dbg("skipping drv id %s", ent);
+			continue;
+		}
+
+		driver_id = (uint16_t) val;
+		path = g_build_filename(base_store, ent, NULL);
+		tmplist = scan_driver_store_dir(path, driver_id, tmplist);
+		g_free(path);
+	}
+
+	g_dir_close(dir);
+	tmplist_len = g_slist_length(tmplist);
+	list = g_malloc(sizeof(*list) * (tmplist_len + 1));
+	elem = tmplist;
+	for (i = 0; i < tmplist_len; i++, elem = g_slist_next(elem))
+		list[i] = elem->data;
+	list[tmplist_len] = NULL; /* NULL-terminate */
+
+	g_slist_free(tmplist);
+	return list;
+}
+
+API_EXPORTED void fp_dscv_prints_free(struct fp_dscv_print **prints)
+{
+	int i;
+	struct fp_dscv_print *print;
+
+	if (!prints)
+		return;
+
+	for (i = 0; print = prints[i]; i++) {
+		if (print)
+			g_free(print->path);
+		g_free(print);
+	}
+	g_free(prints);
+}
+
+API_EXPORTED uint16_t fp_dscv_print_get_driver_id(struct fp_dscv_print *print)
+{
+	return print->driver_id;
+}
+
+API_EXPORTED uint32_t fp_dscv_print_get_devtype(struct fp_dscv_print *print)
+{
+	return print->devtype;
+}
+
+API_EXPORTED enum fp_finger fp_dscv_print_get_finger(struct fp_dscv_print *print)
+{
+	return print->finger;
+}