cmake: fix libusb search
[libam7xxx.git] / src / am7xxx.c
index 7ef981e..b63067e 100644 (file)
@@ -18,7 +18,9 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 #include <errno.h>
+#include <libusb.h>
 
 #include "am7xxx.h"
 #include "serialize.h"
 #define AM7XXX_VENDOR_ID  0x1de1
 #define AM7XXX_PRODUCT_ID 0xc101
 
+/* The header size on the wire is known to be always 24 bytes, regardless of
+ * the memory configuration enforced by different architechtures or compilers
+ * for struct am7xxx_header
+ */
+#define AM7XXX_HEADER_WIRE_SIZE 24
+
+struct _am7xxx_device {
+       libusb_device_handle *usb_device;
+       uint8_t buffer[AM7XXX_HEADER_WIRE_SIZE];
+};
+
 typedef enum {
        AM7XXX_PACKET_TYPE_DEVINFO = 0x01,
        AM7XXX_PACKET_TYPE_IMAGE   = 0x02,
@@ -70,12 +83,6 @@ struct am7xxx_power_header {
  * 04 00 00 00 00 0c ff ff 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00
  */
 
-/* The header size on the wire is known to be always 24 bytes, regardless of
- * the memory configuration enforced by different architechtures or compilers
- * for struct am7xxx_header
- */
-#define AM7XXX_HEADER_WIRE_SIZE 24
-
 struct am7xxx_header {
        uint32_t packet_type;
        uint8_t unknown0;
@@ -178,12 +185,12 @@ static void dump_buffer(uint8_t *buffer, unsigned int len)
        fflush(stdout);
 }
 
-static int read_data(am7xxx_device dev, uint8_t *buffer, unsigned int len)
+static int read_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 {
        int ret;
-       int transferred;
+       int transferred = 0;
 
-       ret = libusb_bulk_transfer(dev, 0x81, buffer, len, &transferred, 0);
+       ret = libusb_bulk_transfer(dev->usb_device, 0x81, buffer, len, &transferred, 0);
        if (ret != 0 || (unsigned int)transferred != len) {
                fprintf(stderr, "Error: ret: %d\ttransferred: %d (expected %u)\n",
                        ret, transferred, len);
@@ -199,10 +206,10 @@ static int read_data(am7xxx_device dev, uint8_t *buffer, unsigned int len)
        return 0;
 }
 
-static int send_data(am7xxx_device dev, uint8_t *buffer, unsigned int len)
+static int send_data(am7xxx_device *dev, uint8_t *buffer, unsigned int len)
 {
        int ret;
-       int transferred;
+       int transferred = 0;
 
 #if DEBUG
        printf("\nsending -->\n");
@@ -210,7 +217,7 @@ static int send_data(am7xxx_device dev, uint8_t *buffer, unsigned int len)
        printf("\n");
 #endif
 
-       ret = libusb_bulk_transfer(dev, 1, buffer, len, &transferred, 0);
+       ret = libusb_bulk_transfer(dev->usb_device, 1, buffer, len, &transferred, 0);
        if (ret != 0 || (unsigned int)transferred != len) {
                fprintf(stderr, "Error: ret: %d\ttransferred: %d (expected %u)\n",
                        ret, transferred, len);
@@ -250,22 +257,15 @@ static void unserialize_header(uint8_t *buffer, struct am7xxx_header *h)
        h->header_data.data.field3 = get_le32(buffer_iterator);
 }
 
-static int read_header(am7xxx_device dev, struct am7xxx_header *h)
+static int read_header(am7xxx_device *dev, struct am7xxx_header *h)
 {
-       uint8_t *buffer;
        int ret;
 
-       buffer = calloc(AM7XXX_HEADER_WIRE_SIZE, 1);
-       if (buffer == NULL) {
-               perror("calloc buffer");
-               return -ENOMEM;
-       }
-
-       ret = read_data(dev, buffer, AM7XXX_HEADER_WIRE_SIZE);
+       ret = read_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
        if (ret < 0)
                goto out;
 
-       unserialize_header(buffer, h);
+       unserialize_header(dev->buffer, h);
 
 #if DEBUG
        printf("\n");
@@ -276,13 +276,11 @@ static int read_header(am7xxx_device dev, struct am7xxx_header *h)
        ret = 0;
 
 out:
-       free(buffer);
        return ret;
 }
 
-static int send_header(am7xxx_device dev, struct am7xxx_header *h)
+static int send_header(am7xxx_device *dev, struct am7xxx_header *h)
 {
-       uint8_t *buffer;
        int ret;
 
 #if DEBUG
@@ -291,56 +289,60 @@ static int send_header(am7xxx_device dev, struct am7xxx_header *h)
        printf("\n");
 #endif
 
-       buffer = calloc(AM7XXX_HEADER_WIRE_SIZE, 1);
-       if (buffer == NULL) {
-               perror("calloc buffer");
-               return -ENOMEM;
-       }
-
-       serialize_header(h, buffer);
-       ret = send_data(dev, buffer, AM7XXX_HEADER_WIRE_SIZE);
+       serialize_header(h, dev->buffer);
+       ret = send_data(dev, dev->buffer, AM7XXX_HEADER_WIRE_SIZE);
        if (ret < 0)
                fprintf(stderr, "send_header: failed to send data.\n");
 
-       free(buffer);
        return ret;
 }
 
-am7xxx_device am7xxx_init(void)
+am7xxx_device *am7xxx_init(void)
 {
-       am7xxx_device dev;
+       unsigned int i;
+
+       am7xxx_device *dev = malloc(sizeof(*dev));
+       if (dev == NULL) {
+               perror("malloc");
+               goto out;
+       }
+       memset(dev, 0, sizeof(*dev));
 
        libusb_init(NULL);
        libusb_set_debug(NULL, 3);
 
-       dev = libusb_open_device_with_vid_pid(NULL,
+       dev->usb_device = libusb_open_device_with_vid_pid(NULL,
                                              AM7XXX_VENDOR_ID,
                                              AM7XXX_PRODUCT_ID);
-       if (dev == NULL) {
+       if (dev->usb_device == NULL) {
                errno = ENODEV;
                perror("libusb_open_device_with_vid_pid");
                goto out_libusb_exit;
        }
 
-       libusb_set_configuration(dev, 1);
-       libusb_claim_interface(dev, 0);
+       libusb_set_configuration(dev->usb_device, 1);
+       libusb_claim_interface(dev->usb_device, 0);
 
        return dev;
 
 out_libusb_exit:
        libusb_exit(NULL);
+       free(dev);
+out:
        return NULL;
 }
 
-void am7xxx_shutdown(am7xxx_device dev)
+void am7xxx_shutdown(am7xxx_device *dev)
 {
        if (dev) {
-               libusb_close(dev);
+               libusb_close(dev->usb_device);
                libusb_exit(NULL);
+               free(dev);
+               dev = NULL;
        }
 }
 
-int am7xxx_get_device_info(am7xxx_device dev,
+int am7xxx_get_device_info(am7xxx_device *dev,
                           unsigned int *native_width,
                           unsigned int *native_height,
                           unsigned int *unknown0,
@@ -379,7 +381,7 @@ int am7xxx_get_device_info(am7xxx_device dev,
        return 0;
 }
 
-int am7xxx_send_image(am7xxx_device dev,
+int am7xxx_send_image(am7xxx_device *dev,
                      am7xxx_image_format format,
                      unsigned int width,
                      unsigned int height,
@@ -413,7 +415,7 @@ int am7xxx_send_image(am7xxx_device dev,
        return send_data(dev, image, size);
 }
 
-int am7xxx_set_power_mode(am7xxx_device dev, am7xxx_power_mode mode)
+int am7xxx_set_power_mode(am7xxx_device *dev, am7xxx_power_mode mode)
 {
        int ret;
        struct am7xxx_header h = {