gracefully handle errors on socket-write

[hmcfgusb] / hmcfgusb.c

diff --git a/hmcfgusb.c b/hmcfgusb.c
index a73cd65e6d6a8713d544b76276fb9166afe48567..7ec07142553c45b86a587df47c2213632eb7f7df 100644 (file)
--- a/hmcfgusb.c
+++ b/hmcfgusb.c
@@ -49,7 +49,7 @@
 #define INTERFACE      0
 
 static int quit = 0;
-static int debug = 1;
+static int debug = 0;
 
 /* Not in all libusb-1.0 versions, so we have to roll our own :-( */
 static char * usb_strerror(int e)
@@ -145,7 +145,7 @@ int hmcfgusb_send(struct hmcfgusb_dev *usbdev, unsigned char* send_data, int len
        int cnt;
 
        if (debug)
-               hexdump(send_data, len, "< ");
+               hexdump(send_data, len, "USB < ");
        err = libusb_interrupt_transfer(usbdev->usb_devh, EP_OUT, send_data, len, &cnt, USB_TIMEOUT);
        if (err) {
                fprintf(stderr, "Can't send data: %s\n", usb_strerror(err));
@@ -191,7 +191,6 @@ static struct libusb_transfer *hmcfgusb_prepare_int(libusb_device_handle *devh,
        if (err != 0) {
                fprintf(stderr, "Can't submit transfer: %s\n", usb_strerror(err));
                libusb_free_transfer(transfer);
-               free(data_buf);
                return NULL;
        }
 
@@ -225,8 +224,18 @@ static void LIBUSB_CALL hmcfgusb_interrupt(struct libusb_transfer *transfer)
        } else {
                if (cb_data && cb_data->cb) {
                        if (debug)
-                               hexdump(transfer->buffer, transfer->actual_length, "> ");
-                       cb_data->cb(transfer->buffer, transfer->actual_length, cb_data->data);
+                               hexdump(transfer->buffer, transfer->actual_length, "USB > ");
+
+                       if (!cb_data->cb(transfer->buffer, transfer->actual_length, cb_data->data)) {
+                               quit = EIO;
+
+                               if (cb_data && cb_data->dev && cb_data->dev->transfer) {
+                                       libusb_free_transfer(cb_data->dev->transfer);
+                                       cb_data->dev->transfer = NULL;
+                               }
+
+                               return;
+                       }
                } else {
                        hexdump(transfer->buffer, transfer->actual_length, "> ");
                }
@@ -235,7 +244,6 @@ static void LIBUSB_CALL hmcfgusb_interrupt(struct libusb_transfer *transfer)
        err = libusb_submit_transfer(transfer);
        if (err != 0) {
                fprintf(stderr, "Can't re-submit transfer: %s\n", usb_strerror(err));
-               free(transfer->buffer);
                libusb_free_transfer(transfer);
        }
 }
@@ -317,6 +325,8 @@ struct hmcfgusb_dev *hmcfgusb_init(hmcfgusb_cb_fn cb, void *data)
 
        dev->n_pfd = dev->n_usb_pfd;
 
+       quit = 0;
+
        return dev;
 }
 
@@ -370,6 +380,7 @@ int hmcfgusb_poll(struct hmcfgusb_dev *dev, int timeout)
                n = poll(dev->pfd, dev->n_pfd, tv.tv_sec * 1000);
                if (n < 0) {
                        perror("poll");
+                       errno = 0;
                        return -1;
                } else if (n == 0) {
                        usb_event = 1;
@@ -380,6 +391,7 @@ int hmcfgusb_poll(struct hmcfgusb_dev *dev, int timeout)
                                                usb_event = 1;
                                                break;
                                        } else {
+                                               errno = 0;
                                                return dev->pfd[fd_n].fd;
                                        }
                                }
@@ -397,8 +409,11 @@ int hmcfgusb_poll(struct hmcfgusb_dev *dev, int timeout)
                }
        }
 
-       if (quit)
+       errno = 0;
+       if (quit) {
+               fprintf(stderr, "closing device-connection due to error %d\n", quit);
                errno = quit;
+       }
 
        return -1;
 }
@@ -422,3 +437,8 @@ void hmcfgusb_close(struct hmcfgusb_dev *dev)
 
        libusb_exit(NULL);
 }
+
+void hmcfgusb_set_debug(int d)
+{
+       debug = d;
+}