diff --git a/src/lib.c b/src/lib.c
new file mode 100644
index 0000000..2ca4717
--- /dev/null
+++ b/src/lib.c
@@ -0,0 +1,236 @@
+// Library frontend functions
+// Copyright 2022 by Daniel C (https://github.com/petabyt/camlib)
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <camlib.h>
+#include <ptp.h>
+
+// Reset all fields of PtpRuntime - this must be updated when new fields are added
+void ptp_generic_reset(struct PtpRuntime *r) {
+	r->active_connection = 0;
+	r->transaction = 0;
+	r->session = 0;	
+	r->connection_type = PTP_USB;
+	r->caller_unlocks_mutex = 0;
+	r->mutex = NULL;
+	r->wait_for_response = 1;
+}
+
+void ptp_generic_init(struct PtpRuntime *r) {
+	memset(r, 0, sizeof(struct PtpRuntime));
+	ptp_generic_reset(r);
+
+	r->data = malloc(CAMLIB_DEFAULT_SIZE);
+	r->data_length = CAMLIB_DEFAULT_SIZE;
+
+	#ifndef CAMLIB_DONT_USE_MUTEX
+	r->mutex = malloc(sizeof(pthread_mutex_t));
+	if (pthread_mutex_init(r->mutex, NULL)) {
+		ptp_verbose_log("Failed to init mutex\n");
+		free(r->mutex);
+		r->mutex = NULL;
+	}
+	#endif
+}
+
+struct PtpRuntime *ptp_generic_new() {
+	struct PtpRuntime *r = malloc(sizeof(struct PtpRuntime));
+	ptp_generic_init(r);
+	return r;
+}
+
+#define BUF_EXTRA 1000
+int ptp_buffer_resize(struct PtpRuntime *r, size_t size) {
+	ptp_verbose_log("Extending IO buffer to %X\n", size + BUF_EXTRA);
+	r->data = realloc(r->data, size + BUF_EXTRA);
+	r->data_length = size + BUF_EXTRA;
+	if (r->data == NULL) {
+		return PTP_OUT_OF_MEM;
+	}
+
+	return 0;
+}
+
+void ptp_mutex_lock(struct PtpRuntime *r) {
+	if (r->mutex == NULL) return;
+	pthread_mutex_lock(r->mutex);
+}
+
+void ptp_mutex_keep_locked(struct PtpRuntime *r) {
+	r->caller_unlocks_mutex = 1;
+}
+
+void ptp_mutex_unlock(struct PtpRuntime *r) {
+	if (r->mutex == NULL) return;
+	pthread_mutex_unlock(r->mutex);
+	r->caller_unlocks_mutex = 0;
+}
+
+void ptp_generic_close(struct PtpRuntime *r) {
+	free(r->data);
+}
+
+// Perform a generic command transaction - no data phase
+int ptp_generic_send(struct PtpRuntime *r, struct PtpCommand *cmd) {
+	ptp_mutex_lock(r);
+
+	r->data_phase_length = 0;
+
+	int length = ptp_new_cmd_packet(r, cmd);
+	if (ptp_send_bulk_packets(r, length) != length) {
+		ptp_mutex_unlock(r);
+		ptp_verbose_log("Didn't send all packets\n");
+		return PTP_IO_ERR;
+	}
+
+	if (ptp_receive_bulk_packets(r) < 0) {
+		ptp_mutex_unlock(r);
+		ptp_verbose_log("Failed to recieve packets\n");
+		return PTP_IO_ERR;
+	}
+
+	if (ptp_get_last_transaction(r) != r->transaction) {
+		ptp_verbose_log("Mismatch transaction ID\n");
+		ptp_mutex_unlock(r);
+		return PTP_IO_ERR;
+	}
+
+	r->transaction++;
+
+	if (ptp_get_return_code(r) == PTP_RC_OK) {
+		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
+		return 0;
+	} else {
+		ptp_verbose_log("Invalid return code: %X\n", ptp_get_return_code(r));
+		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
+		return PTP_CHECK_CODE;
+	}
+}
+
+// Perform a command request with a data phase to the camera
+int ptp_generic_send_data(struct PtpRuntime *r, struct PtpCommand *cmd, void *data, int length) {
+	ptp_mutex_lock(r);
+
+	// Required for libWPD backend
+	r->data_phase_length = length;
+
+	// TODO: Expand buffer if needed
+	// (Header packet will never be more than 100 bytes)
+	if (length + 100 > r->data_length) {
+		ptp_verbose_log("ptp_generic_send_data: Not enough memory\n");
+		ptp_mutex_unlock(r);
+		return PTP_OUT_OF_MEM;
+	}
+
+	// Send operation request (data phase later on)
+	int plength = ptp_new_cmd_packet(r, cmd);
+	if (ptp_send_bulk_packets(r, plength) != plength) {
+		ptp_mutex_unlock(r);
+		return PTP_IO_ERR;
+	}
+
+	if (r->connection_type == PTP_IP) {
+		// Send data start packet first (only has payload length)
+		plength = ptpip_data_start_packet(r, length);
+		if (ptp_send_bulk_packets(r, plength) != plength) {
+			ptp_mutex_unlock(r);
+			return PTP_IO_ERR;
+		}
+
+		// Send data end packet, with payload
+		plength = ptpip_data_end_packet(r, data, length);
+		if (ptp_send_bulk_packets(r, plength) != plength) {
+			ptp_mutex_unlock(r);
+			return PTP_IO_ERR;
+		}
+	} else {
+		// Single data packet
+		plength = ptp_new_data_packet(r, cmd, data, length);
+		if (ptp_send_bulk_packets(r, plength) != plength) {
+			ptp_mutex_unlock(r);
+			ptp_verbose_log("Failed to send data packet (%d)\n", plength);
+			return PTP_IO_ERR;
+		}
+	}
+
+	if (ptp_receive_bulk_packets(r) < 0) {
+		ptp_mutex_unlock(r);
+		return PTP_IO_ERR;
+	}
+
+	if (ptp_get_last_transaction(r) != r->transaction) {
+		ptp_verbose_log("ptp_generic_send_data: Mismatch transaction ID (%d/%d)\n",
+			ptp_get_last_transaction(r), r->transaction);
+		ptp_mutex_unlock(r);
+		return PTP_IO_ERR;
+	}
+
+	r->transaction++;
+
+	if (ptp_get_return_code(r) == PTP_RC_OK) {
+		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
+		return 0;
+	} else {
+		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
+		return PTP_CHECK_CODE;
+	}
+}
+
+struct UintArray *ptp_dup_uint_array(struct UintArray *arr) {
+	struct UintArray *arr2 = malloc(4 + arr->length * 4);
+	if (arr2 == NULL) return NULL;
+	memcpy(arr2, arr, 4 + arr->length * 4);
+	return arr2;
+}
+
+int ptp_device_type(struct PtpRuntime *r) {
+	struct PtpDeviceInfo *di = r->di;
+	if (di == NULL) return PTP_DEV_EMPTY;
+	if (!strcmp(di->manufacturer, "Canon Inc.")) {
+		if (ptp_check_opcode(r, PTP_OC_EOS_GetStorageIDs)) {
+			return PTP_DEV_EOS;
+		}
+
+		return PTP_DEV_CANON;
+	} else if (!strcmp(di->manufacturer, "FUJIFILM")) {
+		return PTP_DEV_FUJI;
+	} else if (!strcmp(di->manufacturer, "Sony Corporation")) {
+		return PTP_DEV_SONY;
+	} else if (!strcmp(di->manufacturer, "Nikon Corporation")) {
+		return PTP_DEV_NIKON;
+	}
+
+	return PTP_DEV_EMPTY;
+}
+
+int ptp_check_opcode(struct PtpRuntime *r, int op) {
+	if (r->di == NULL) return 0;
+	for (int i = 0; i < r->di->ops_supported_length; i++) {
+		if (r->di->ops_supported[i] == op) {
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int ptp_check_prop(struct PtpRuntime *r, int code) {
+	if (r->di == NULL) return 0;
+	for (int i = 0; i < r->di->props_supported_length; i++) {
+		if (r->di->props_supported[i] == code) {
+			return 1;
+		}
+	}
+
+	return 0;
+}
+
+int ptp_dump(struct PtpRuntime *r) {
+	FILE *f = fopen("DUMP", "w");
+	fwrite(r->data, r->data_length, 1, f);
+	fclose(f);
+	return 0;
+}
diff --git a/src/util.c b/src/util.c
index 0595f5c..578b7d1 100644
--- a/src/util.c
+++ b/src/util.c
@@ -1,224 +1,2 @@
-// Library frontend functions
-// Copyright 2022 by Daniel C (https://github.com/petabyt/camlib)
-
-#include <stdlib.h>
-#include <stdio.h>
-#include <string.h>
-
-#include <camlib.h>
-#include <ptp.h>
-
-void ptp_generic_reset(struct PtpRuntime *r) {
-	r->active_connection = 0;
-	r->transaction = 0;
-	r->session = 0;	
-	r->connection_type = PTP_USB;
-	r->caller_unlocks_mutex = 0;
-	r->mutex = NULL;
-	r->wait_for_response = 1;
-}
-
-void ptp_generic_init(struct PtpRuntime *r) {
-	memset(r, 0, sizeof(struct PtpRuntime));
-	ptp_generic_reset(r);
-
-	r->data = malloc(CAMLIB_DEFAULT_SIZE);
-	r->data_length = CAMLIB_DEFAULT_SIZE;
-
-	#ifndef CAMLIB_DONT_USE_MUTEX
-	r->mutex = malloc(sizeof(pthread_mutex_t));
-	if (pthread_mutex_init(r->mutex, NULL)) {
-		ptp_verbose_log("Failed to init mutex\n");
-		free(r->mutex);
-		r->mutex = NULL;
-	}
-	#endif
-}
-
-struct PtpRuntime *ptp_generic_new() {
-	struct PtpRuntime *r = malloc(sizeof(struct PtpRuntime));
-	ptp_generic_init(r);
-	return r;
-}
-
-void ptp_mutex_lock(struct PtpRuntime *r) {
-	if (r->mutex == NULL) return;
-	pthread_mutex_lock(r->mutex);
-}
-
-void ptp_mutex_keep_locked(struct PtpRuntime *r) {
-	r->caller_unlocks_mutex = 1;
-}
-
-void ptp_mutex_unlock(struct PtpRuntime *r) {
-	if (r->mutex == NULL) return;
-	pthread_mutex_unlock(r->mutex);
-	r->caller_unlocks_mutex = 0;
-}
-
-void ptp_generic_close(struct PtpRuntime *r) {
-	free(r->data);
-}
-
-// Perform a "generic" command type transaction. Could be a macro, but macros suck.
-int ptp_generic_send(struct PtpRuntime *r, struct PtpCommand *cmd) {
-	ptp_mutex_lock(r);
-
-	r->data_phase_length = 0;
-
-	int length = ptp_new_cmd_packet(r, cmd);
-	if (ptp_send_bulk_packets(r, length) != length) {
-		ptp_mutex_unlock(r);
-		ptp_verbose_log("Didn't send all packets\n");
-		return PTP_IO_ERR;
-	}
-
-	if (ptp_receive_bulk_packets(r) < 0) {
-		ptp_mutex_unlock(r);
-		ptp_verbose_log("Failed to recieve packets\n");
-		return PTP_IO_ERR;
-	}
-
-	if (ptp_get_last_transaction(r) != r->transaction) {
-		ptp_verbose_log("Mismatch transaction ID\n");
-		ptp_mutex_unlock(r);
-		return PTP_IO_ERR;
-	}
-
-	r->transaction++;
-
-	if (ptp_get_return_code(r) == PTP_RC_OK) {
-		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
-		return 0;
-	} else {
-		ptp_verbose_log("Invalid return code: %X\n", ptp_get_return_code(r));
-		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
-		return PTP_CHECK_CODE;
-	}
-}
-
-// Send a cmd packet, then data packet
-// Perform a generic operation with a data phase to the camera
-int ptp_generic_send_data(struct PtpRuntime *r, struct PtpCommand *cmd, void *data, int length) {
-	ptp_mutex_lock(r);
-
-	r->data_phase_length = length;
-
-	// TODO: Expand buffer if needed
-	// (Header packet will never be more than 100 bytes)
-	if (length + 100 > r->data_length) {
-		ptp_verbose_log("ptp_generic_send_data: Not enough memory\n");
-		ptp_mutex_unlock(r);
-		return PTP_OUT_OF_MEM;
-	}
-
-	// Send operation request packet data phase 2
-	int plength = ptp_new_cmd_packet(r, cmd);
-	if (ptp_send_bulk_packets(r, plength) != plength) {
-		ptp_mutex_unlock(r);
-		return PTP_IO_ERR;
-	}
-
-	if (r->connection_type == PTP_IP) {
-		// Send data start packet first (only has payload length)
-		plength = ptpip_data_start_packet(r, length);
-		if (ptp_send_bulk_packets(r, plength) != plength) {
-			ptp_mutex_unlock(r);
-			return PTP_IO_ERR;
-		}
-
-		// Send data end packet, with payload
-		plength = ptpip_data_end_packet(r, data, length);
-		if (ptp_send_bulk_packets(r, plength) != plength) {
-			ptp_mutex_unlock(r);
-			return PTP_IO_ERR;
-		}
-	} else {
-		// Single data packet
-		plength = ptp_new_data_packet(r, cmd, data, length);
-		if (ptp_send_bulk_packets(r, plength) != plength) {
-			ptp_mutex_unlock(r);
-			ptp_verbose_log("Failed to send data packet (%d)\n", plength);
-			return PTP_IO_ERR;
-		}
-	}
-
-	if (ptp_receive_bulk_packets(r) < 0) {
-		ptp_mutex_unlock(r);
-		return PTP_IO_ERR;
-	}
-
-	if (ptp_get_last_transaction(r) != r->transaction) {
-		ptp_verbose_log("ptp_generic_send_data: Mismatch transaction ID (%d/%d)\n",
-			ptp_get_last_transaction(r), r->transaction);
-		ptp_mutex_unlock(r);
-		return PTP_IO_ERR;
-	}
-
-	r->transaction++;
-
-	if (ptp_get_return_code(r) == PTP_RC_OK) {
-		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
-		return 0;
-	} else {
-		if (!r->caller_unlocks_mutex) ptp_mutex_unlock(r);
-		return PTP_CHECK_CODE;
-	}
-}
-
-struct UintArray *ptp_dup_uint_array(struct UintArray *arr) {
-	struct UintArray *arr2 = malloc(4 + arr->length * 4);
-	if (arr2 == NULL) return NULL;
-	memcpy(arr2, arr, 4 + arr->length * 4);
-	return arr2;
-}
-
-// TODO: maybe 'cache' dev type
-int ptp_device_type(struct PtpRuntime *r) {
-	struct PtpDeviceInfo *di = r->di;
-	if (di == NULL) return PTP_DEV_EMPTY;
-	if (!strcmp(di->manufacturer, "Canon Inc.")) {
-		if (ptp_check_opcode(r, PTP_OC_EOS_GetStorageIDs)) {
-			return PTP_DEV_EOS;
-		}
-
-		return PTP_DEV_CANON;
-	} else if (!strcmp(di->manufacturer, "FUJIFILM")) {
-		return PTP_DEV_FUJI;
-	} else if (!strcmp(di->manufacturer, "Sony Corporation")) {
-		return PTP_DEV_SONY;
-	} else if (!strcmp(di->manufacturer, "Nikon Corporation")) {
-		return PTP_DEV_NIKON;
-	}
-
-	return PTP_DEV_EMPTY;
-}
-
-int ptp_check_opcode(struct PtpRuntime *r, int op) {
-	if (r->di == NULL) return 0;
-	for (int i = 0; i < r->di->ops_supported_length; i++) {
-		if (r->di->ops_supported[i] == op) {
-			return 1;
-		}
-	}
-
-	return 0;
-}
-
-int ptp_check_prop(struct PtpRuntime *r, int code) {
-	if (r->di == NULL) return 0;
-	for (int i = 0; i < r->di->props_supported_length; i++) {
-		if (r->di->props_supported[i] == code) {
-			return 1;
-		}
-	}
-
-	return 0;
-}
-
-int ptp_dump(struct PtpRuntime *r) {
-	FILE *f = fopen("DUMP", "w");
-	fwrite(r->data, r->data_length, 1, f);
-	fclose(f);
-	return 0;
-}
+#warning "util.c has been renamed to lib.c"
+#include "lib.c"