nfc_target_send_bits() function returns now sent bits count on success and libnfc error code on failure.

examples/nfc-emulate-uid.c

@@ -205,7 +205,7 @@ main (int argc, char *argv[])
       // Test if we know how to respond
       if (szTxBits) {
         // Send and print the command to the screen
-        if (!nfc_target_send_bits (pnd, pbtTx, szTxBits, NULL)) {
+        if (nfc_target_send_bits (pnd, pbtTx, szTxBits, NULL) < 0) {
           nfc_perror (pnd, "nfc_target_send_bits");
           goto error;
         }

examples/nfc-relay.c

@@ -199,7 +199,7 @@ main (int argc, char *argv[])
       if (nfc_initiator_transceive_bits
           (pndReader, abtReaderRx, szReaderRxBits, abtReaderRxPar, abtTagRx, &szTagRxBits, abtTagRxPar) > 0) {
         // Redirect the answer back to the reader
-        if (!nfc_target_send_bits (pndTag, abtTagRx, szTagRxBits, abtTagRxPar)) {
+        if (nfc_target_send_bits (pndTag, abtTagRx, szTagRxBits, abtTagRxPar) < 0) {
           nfc_perror (pndTag, "nfc_target_send_bits");
           exit (EXIT_FAILURE);
         }

include/nfc/nfc.h

@@ -86,7 +86,7 @@ extern  "C" {
   NFC_EXPORT int nfc_target_init (nfc_device *pnd, nfc_target *pnt, uint8_t *pbtRx, size_t *pszRx);
   NFC_EXPORT int nfc_target_send_bytes (nfc_device *pnd, const uint8_t *pbtTx, const size_t szTx, int timeout);
   NFC_EXPORT int nfc_target_receive_bytes (nfc_device *pnd, uint8_t *pbtRx, size_t *pszRx, int timeout);
-  NFC_EXPORT bool nfc_target_send_bits (nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar);
+  NFC_EXPORT int nfc_target_send_bits (nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar);
   NFC_EXPORT bool nfc_target_receive_bits (nfc_device *pnd, uint8_t *pbtRx, size_t *pszRxBits, uint8_t *pbtRxPar);
 
 /* Error reporting */

libnfc/chips/pn53x.c

@@ -1831,13 +1831,14 @@ pn53x_target_receive_bytes (struct nfc_device *pnd, uint8_t *pbtRx, size_t *pszR
   return *pszRx;
 }
 
-bool
+int
 pn53x_target_send_bits (struct nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar)
 {
   size_t  szFrameBits = 0;
   size_t  szFrameBytes = 0;
   uint8_t ui8Bits = 0;
   uint8_t  abtCmd[PN53x_EXTENDED_FRAME__DATA_MAX_LEN] = { TgResponseToInitiator };
+  int res = 0;
 
   // Check if we should prepare the parity bits ourself
   if (!pnd->bPar) {
@@ -1858,15 +1859,15 @@ pn53x_target_send_bits (struct nfc_device *pnd, const uint8_t *pbtTx, const size
     memcpy (abtCmd + 1, pbtTx, szFrameBytes);
 
   // Set the amount of transmission bits in the PN53X chip register
-  if (pn53x_set_tx_bits (pnd, ui8Bits) < 0)
+  if ((res = pn53x_set_tx_bits (pnd, ui8Bits)) < 0)
-    return false;
+    return res;
 
   // Try to send the bits to the reader
-  if (pn53x_transceive (pnd, abtCmd, szFrameBytes + 1, NULL, NULL, -1) < 0)
+  if ((res = pn53x_transceive (pnd, abtCmd, szFrameBytes + 1, NULL, NULL, -1)) < 0)
-    return false;
+    return res;
 
-  // Everyting seems ok, return true
+  // Everyting seems ok, return return sent bits count
-  return true;
+  return szTxBits;
 }
 
 int

libnfc/chips/pn53x.h

@@ -315,7 +315,7 @@ int    pn53x_initiator_deselect_target (struct nfc_device *pnd);
 int    pn53x_target_init (struct nfc_device *pnd, nfc_target *pnt, uint8_t *pbtRx, size_t *pszRx);
 bool    pn53x_target_receive_bits (struct nfc_device *pnd, uint8_t *pbtRx, size_t *pszRxBits, uint8_t *pbtRxPar);
 int    pn53x_target_receive_bytes (struct nfc_device *pnd, uint8_t *pbtRx, size_t *pszRx, int timeout);
-bool    pn53x_target_send_bits (struct nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar);
+int    pn53x_target_send_bits (struct nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar);
 int    pn53x_target_send_bytes (struct nfc_device *pnd, const uint8_t *pbtTx, const size_t szTx, int timeout);
 
 // Error handling functions

libnfc/nfc-internal.h

@@ -145,7 +145,7 @@ struct nfc_driver_t {
   int (*target_init) (struct nfc_device *pnd, nfc_target * pnt, uint8_t * pbtRx, size_t * pszRx);
   int (*target_send_bytes) (struct nfc_device *pnd, const uint8_t * pbtTx, const size_t szTx, int timeout);
   int (*target_receive_bytes) (struct nfc_device *pnd, uint8_t * pbtRx, size_t * pszRx, int timeout);
-  bool (*target_send_bits) (struct nfc_device *pnd, const uint8_t * pbtTx, const size_t szTxBits, const uint8_t * pbtTxPar);
+  int (*target_send_bits) (struct nfc_device *pnd, const uint8_t * pbtTx, const size_t szTxBits, const uint8_t * pbtTxPar);
   bool (*target_receive_bits) (struct nfc_device *pnd, uint8_t * pbtRx, size_t * pszRxBits, uint8_t * pbtRxPar);
 
   int (*device_set_property_bool) (struct nfc_device *pnd, const nfc_property property, const bool bEnable);

libnfc/nfc.c

@@ -736,12 +736,12 @@ nfc_target_receive_bytes (nfc_device *pnd, uint8_t *pbtRx, size_t *pszRx, int ti
 
 /**
  * @brief Send raw bit-frames
- * @return Returns \c true if action was successfully performed; otherwise returns \c false.
+ * @return Returns sent bits count on success, otherwise returns libnfc's error code.
  *
  * This function can be used to transmit (raw) bit-frames to the \e initiator
  * using the specified NFC device (configured as \e target).
  */
-bool
+int
 nfc_target_send_bits (nfc_device *pnd, const uint8_t *pbtTx, const size_t szTxBits, const uint8_t *pbtTxPar)
 {
   HAL (target_send_bits, pnd, pbtTx, szTxBits, pbtTxPar);