Remove nfc-defines.h public header.

Use NULL instead of INVALID_DEVICE_INFO to know if device is valid.
Make distcheck OK

src/examples/mifaretag.h

@@ -24,8 +24,6 @@
 #ifndef _LIBNFC_MIFARE_TAG_H_
 #define _LIBNFC_MIFARE_TAG_H_
 
-#include "nfc-defines.h"
-
 typedef struct {
   byte_t abtUID[4];
   byte_t btBCC;

src/examples/mifareultag.h

@@ -24,8 +24,6 @@
 #ifndef _LIBNFC_MIFARE_UL_TAG_H_
 #define _LIBNFC_MIFARE_UL_TAG_H_
 
-#include "nfc-defines.h"
-
 typedef struct {
   byte_t sn0[3];
   byte_t btBCC0;

src/examples/nfc-anticol.c

@@ -35,6 +35,8 @@
 
 #define SAK_FLAG_ATS_SUPPORTED 0x20
 
+#define MAX_FRAME_LEN 264
+
 static byte_t abtRx[MAX_FRAME_LEN];
 static size_t szRxBits;
 static size_t szRxLen;

src/examples/nfc-emulate.c

@@ -32,6 +32,8 @@
 #include "nfc-messages.h"
 #include "bitutils.h"
 
+#define MAX_FRAME_LEN 264
+
 static byte_t abtRecv[MAX_FRAME_LEN];
 static size_t szRecvBits;
 static nfc_device_t* pnd;
@@ -87,7 +89,7 @@ int main(int argc, char *argv[])
   // Try to open the NFC reader
   pnd = nfc_connect(NULL);
 
-  if (pnd == INVALID_DEVICE_INFO)
+  if (pnd == NULL)
   {
     printf("Error connecting NFC reader\n");
     return 1;

src/examples/nfc-list.c

@@ -52,7 +52,7 @@ int main(int argc, const char* argv[])
   pnd = nfc_connect(&ndd);
   */
 
-  if (pnd == INVALID_DEVICE_INFO)
+  if (pnd == NULL)
   {
     ERR("Unable to connect to NFC device.");
     return 1;

src/examples/nfc-mfclassic.c

@@ -405,7 +405,7 @@ int main(int argc, const char* argv[])
     
       // Try to open the NFC reader
       pnd = nfc_connect(NULL);
-      if (pnd == INVALID_DEVICE_INFO)
+      if (pnd == NULL)
       {
         printf("Error connecting NFC reader\n");
         return 1;

src/examples/nfc-mfultralight.c

@@ -149,7 +149,7 @@ int main(int argc, const char* argv[])
 
   // Try to open the NFC reader
   pnd = nfc_connect(NULL);
-  if (pnd == INVALID_DEVICE_INFO)
+  if (pnd == NULL)
   {
     printf("Error connecting NFC reader\n");
     return 1;

src/examples/nfc-relay.c

@@ -31,6 +31,8 @@
 #include "nfc-messages.h"
 #include "bitutils.h"
 
+#define MAX_FRAME_LEN 264
+
 static byte_t abtReaderRx[MAX_FRAME_LEN];
 static byte_t abtReaderRxPar[MAX_FRAME_LEN];
 static size_t szReaderRxBits;
@@ -70,7 +72,7 @@ int main(int argc,char* argv[])
 
   // Try to open the NFC emulator device
   pndTag = nfc_connect(NULL);
-  if (pndTag == INVALID_DEVICE_INFO)
+  if (pndTag == NULL)
   {
     printf("Error connecting NFC emulator device\n");
     return 1;
@@ -89,8 +91,8 @@ int main(int argc,char* argv[])
   printf("[+] Thank you, the emulated tag is initialized\n");
 
   // Try to open the NFC reader
-  pndReader = INVALID_DEVICE_INFO;
-  while (pndReader == INVALID_DEVICE_INFO) pndReader = nfc_connect(NULL);
+  pndReader = NULL;
+  while (pndReader == NULL) pndReader = nfc_connect(NULL);
   printf("[+] Configuring NFC reader settings\n");
   nfc_configure(pndReader,DCO_HANDLE_CRC,false);
   nfc_configure(pndReader,DCO_HANDLE_PARITY,false);

src/examples/nfcip-initiator.c

@@ -25,6 +25,8 @@
 #include <string.h>
 #include <nfc.h>
 
+#define MAX_FRAME_LEN 264
+
 int main(int argc, const char *argv[])
 {
   nfc_device_t *pnd;

src/examples/nfcip-target.c

@@ -24,6 +24,8 @@
 #include <stdio.h>
 #include <nfc.h>
 
+#define MAX_FRAME_LEN 264
+
 int main(int argc, const char *argv[])
 {
   byte_t abtRecv[MAX_FRAME_LEN];