hidraw/libusb: fix -Wall -Wextra -pedantic -Werror compilation (#214)

- minor code-style fixes;

hidtest/test.c

@@ -7,7 +7,7 @@
  8/22/2009
 
  Copyright 2009
- 
+
  This contents of this file may be used by anyone
  for any reason without any conditions and may be
  used as a starting point for your own applications
@@ -29,18 +29,16 @@
 
 int main(int argc, char* argv[])
 {
+ (void)argc;
+ (void)argv;
+
  int res;
  unsigned char buf[256];
  #define MAX_STR 255
  wchar_t wstr[MAX_STR];
  hid_device *handle;
  int i;
 
-#ifdef WIN32
- UNREFERENCED_PARAMETER(argc);
- UNREFERENCED_PARAMETER(argv);
-#endif
-
  struct hid_device_info *devs, *cur_dev;
 
  printf("hidapi test/example tool. Compiled with hidapi version %s, runtime version %s.\n", HID_API_VERSION_STR, hid_version_str());
@@ -55,7 +53,7 @@ int main(int argc, char* argv[])
  return -1;
 
  devs = hid_enumerate(0x0, 0x0);
- cur_dev = devs; 
+ cur_dev = devs;
  while (cur_dev) {
  printf("Device Found\n type: %04hx %04hx\n path: %s\n serial_number: %ls", cur_dev->vendor_id, cur_dev->product_id, cur_dev->path, cur_dev->serial_number);
  printf("\n");
@@ -73,7 +71,7 @@ int main(int argc, char* argv[])
  memset(buf,0x00,sizeof(buf));
  buf[0] = 0x01;
  buf[1] = 0x81;
- 
+
 
  // Open the device using the VID, PID,
  // and optionally the Serial number.
@@ -115,7 +113,7 @@ int main(int argc, char* argv[])
 
  // Set the hid_read() function to be non-blocking.
  hid_set_nonblocking(handle, 1);
- 
+
  // Try to read from the device. There should be no
  // data here, but execution should not block.
  res = hid_read(handle, buf, 17);
@@ -158,7 +156,7 @@ int main(int argc, char* argv[])
  printf("Unable to write()\n");
  printf("Error: %ls\n", hid_error(handle));
  }
- 
+
 
  // Request state (cmd 0x81). The first byte is the report number (0x1).
  buf[0] = 0x1;

libusb/hid.c

@@ -1098,18 +1098,21 @@ static void cleanup_mutex(void *param)
 
 int HID_API_EXPORT hid_read_timeout(hid_device *dev, unsigned char *data, size_t length, int milliseconds)
 {
- int bytes_read = -1;
-
 #if 0
  int transferred;
  int res = libusb_interrupt_transfer(dev->device_handle, dev->input_endpoint, data, length, &transferred, 5000);
  LOG("transferred: %d\n", transferred);
  return transferred;
 #endif
+ /* by initialising this variable right here, GCC gives a compilation warning/error: */
+ /* error: variable ‘bytes_read’ might be clobbered by ‘longjmp’ or ‘vfork’ [-Werror=clobbered] */
+ int bytes_read; /* = -1; */
 
  pthread_mutex_lock(&dev->mutex);
  pthread_cleanup_push(&cleanup_mutex, dev);
 
+ bytes_read = -1;
+
  /* There's an input report queued up. Return it. */
  if (dev->input_reports) {
  /* Return the first one */
@@ -1359,6 +1362,7 @@ int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *dev, int string_index
 
 HID_API_EXPORT const wchar_t * HID_API_CALL hid_error(hid_device *dev)
 {
+ (void)dev;
  return L"hid_error is not implemented yet";
 }
 

linux/hid.c

@@ -412,7 +412,7 @@ static int get_hid_report_descriptor_from_sysfs(const char *sysfs_path, struct h
  * strings pointed to by serial_number_utf8 and product_name_utf8 after use.
  */
 static int
-parse_uevent_info(const char *uevent, int *bus_type,
+parse_uevent_info(const char *uevent, unsigned *bus_type,
  unsigned short *vendor_id, unsigned short *product_id,
  char **serial_number_utf8, char **product_name_utf8)
 {
@@ -471,8 +471,8 @@ static int get_device_string(hid_device *dev, enum device_string_id key, wchar_t
  struct udev_device *udev_dev, *parent, *hid_dev;
  struct stat s;
  int ret = -1;
- char *serial_number_utf8 = NULL;
- char *product_name_utf8 = NULL;
+ char *serial_number_utf8 = NULL;
+ char *product_name_utf8 = NULL;
 
  /* Create the udev object */
  udev = udev_new();
@@ -495,7 +495,7 @@ static int get_device_string(hid_device *dev, enum device_string_id key, wchar_t
  if (hid_dev) {
  unsigned short dev_vid;
  unsigned short dev_pid;
- int bus_type;
+ unsigned bus_type;
  size_t retm;
 
  ret = parse_uevent_info(
@@ -567,8 +567,8 @@ static int get_device_string(hid_device *dev, enum device_string_id key, wchar_t
  }
 
 end:
- free(serial_number_utf8);
- free(product_name_utf8);
+ free(serial_number_utf8);
+ free(product_name_utf8);
 
  udev_device_unref(udev_dev);
  /* parent and hid_dev don't need to be (and can't be) unref'd.
@@ -647,7 +647,7 @@ struct hid_device_info HID_API_EXPORT *hid_enumerate(unsigned short vendor_id,
  unsigned short dev_pid;
  char *serial_number_utf8 = NULL;
  char *product_name_utf8 = NULL;
- int bus_type;
+ unsigned bus_type;
  int result;
  struct hidraw_report_descriptor report_desc;
 
@@ -1046,6 +1046,9 @@ int HID_API_EXPORT hid_get_feature_report(hid_device *dev, unsigned char *data,
 // Not supported by Linux HidRaw yet
 int HID_API_EXPORT HID_API_CALL hid_get_input_report(hid_device *dev, unsigned char *data, size_t length)
 {
+ (void)dev;
+ (void)data;
+ (void)length;
  return -1;
 }
 
@@ -1082,6 +1085,10 @@ int HID_API_EXPORT_CALL hid_get_serial_number_string(hid_device *dev, wchar_t *s
 
 int HID_API_EXPORT_CALL hid_get_indexed_string(hid_device *dev, int string_index, wchar_t *string, size_t maxlen)
 {
+ (void)dev;
+ (void)string_index;
+ (void)string;
+ (void)maxlen;
  return -1;
 }