nfc_list_devices() function returns now the number of devices found.

examples/nfc-dep-target.c

@@ -63,11 +63,10 @@ main (int argc, const char *argv[])
 {
   uint8_t  abtRx[MAX_FRAME_LEN];
   int  szRx;
-  size_t  szDeviceFound;
   uint8_t  abtTx[] = "Hello Mars!";
   #define MAX_DEVICE_COUNT 2
   nfc_connstring connstrings[MAX_DEVICE_COUNT];
-  nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szDeviceFound);
+  size_t szDeviceFound = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
   // Little hack to allow using nfc-dep-initiator & nfc-dep-target from
   // the same machine: if there is more than one readers connected
   // nfc-dep-target will connect to the second reader

examples/nfc-relay.c

@@ -82,7 +82,6 @@ main (int argc, char *argv[])
 {
   int     arg;
   bool    quiet_output = false;
-  size_t  szFound;
   const char *acLibnfcVersion = nfc_version ();
 
   // Get commandline options
@@ -110,7 +109,7 @@ main (int argc, char *argv[])
 
   nfc_connstring connstrings[MAX_DEVICE_COUNT];
   // List available devices
-  nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szFound);
+  size_t szFound = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
 
   if (szFound < 2) {
     ERR ("%zd device found but two connected devices are needed to relay NFC.", szFound);

examples/pn53x-diagnose.c

@@ -52,7 +52,6 @@
 int
 main (int argc, const char *argv[])
 {
-  size_t  szFound;
   size_t  i;
   nfc_device *pnd;
   const char *acLibnfcVersion;
@@ -73,7 +72,7 @@ main (int argc, const char *argv[])
   printf ("%s uses libnfc %s\n", argv[0], acLibnfcVersion);
 
   nfc_connstring connstrings[MAX_DEVICE_COUNT];
-  nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szFound);
+  size_t szFound = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
 
   if (szFound == 0) {
     printf ("No NFC device found.\n");

include/nfc/nfc.h

@@ -67,7 +67,7 @@ extern  "C" {
   NFC_EXPORT nfc_device *nfc_connect (const nfc_connstring connstring);
   NFC_EXPORT void nfc_disconnect (nfc_device *pnd);
   NFC_EXPORT int nfc_abort_command (nfc_device *pnd);
-  NFC_EXPORT void nfc_list_devices (nfc_connstring connstrings[], size_t connstrings_len, size_t *pszDeviceFound);
+  NFC_EXPORT size_t nfc_list_devices (nfc_connstring connstrings[], size_t connstrings_len);
   NFC_EXPORT int nfc_idle (nfc_device *pnd);
 
 /* NFC initiator: act as "reader" */

libnfc/nfc.c

@@ -81,9 +81,8 @@ nfc_get_default_device (nfc_connstring *connstring)
   char *env_default_connstring = getenv ("LIBNFC_DEFAULT_DEVICE");
   if (NULL == env_default_connstring) {
     // LIBNFC_DEFAULT_DEVICE is not set, we fallback on probing for the first available device
-    size_t szDeviceFound;
     nfc_connstring listed_cs[1];
-    nfc_list_devices (listed_cs, 1, &szDeviceFound);
+    size_t szDeviceFound = nfc_list_devices (listed_cs, 1);
     if (szDeviceFound) {
       strncpy (*connstring, listed_cs[0], sizeof(nfc_connstring));
     } else {
@@ -177,30 +176,32 @@ nfc_disconnect (nfc_device *pnd)
 
 /**
  * @brief Probe for discoverable supported devices (ie. only available for some drivers)
+ * @return Returns the number of devices found.
  * @param[out] pnddDevices array of \a nfc_device_desc_t previously allocated by the caller.
  * @param szDevices size of the \a pnddDevices array.
- * @param[out] pszDeviceFound number of devices found.
+ * 
  */
-void
+size_t
-nfc_list_devices (nfc_connstring connstrings[] , size_t szDevices, size_t *pszDeviceFound)
+nfc_list_devices (nfc_connstring connstrings[] , size_t szDevices)
 {
-  size_t  szN;
+  size_t szN;
-  *pszDeviceFound = 0;
+  size_t szDeviceFound = 0;
   const struct nfc_driver_t *ndr;
   const struct nfc_driver_t **pndr = nfc_drivers;
 
   log_init ();
   while ((ndr = *pndr)) {
     szN = 0;
-    if (ndr->probe (connstrings + (*pszDeviceFound), szDevices - (*pszDeviceFound), &szN)) {
+    if (ndr->probe (connstrings + (szDeviceFound), szDevices - (szDeviceFound), &szN)) {
-      *pszDeviceFound += szN;
+      szDeviceFound += szN;
       log_put (LOG_CATEGORY, NFC_PRIORITY_TRACE, "%ld device(s) found using %s driver", (unsigned long) szN, ndr->name);
-      if (*pszDeviceFound == szDevices)
+      if (szDeviceFound == szDevices)
 	  break;
     }
     pndr++;
   }
   log_fini ();
+  return szDeviceFound;
 }
 
 /**

test/test_access_storm.c

@@ -15,17 +15,16 @@ test_access_storm (void)
 {
     int n = NTESTS;
     nfc_connstring connstrings[MAX_DEVICE_COUNT];
-    size_t device_count, ref_device_count;
     int res = 0;
 
-    nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &ref_device_count);
+    size_t ref_device_count = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
     if (!ref_device_count)
 	cut_omit ("No NFC device found");
 
     while (n) {
 	size_t i;
 
-	nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &device_count);
+	size_t device_count = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
 	cut_assert_equal_int (ref_device_count, device_count, cut_message ("device count"));
 
 	for (i = 0; i < device_count; i++) {

test/test_dep_active.c

@@ -27,9 +27,7 @@ abort_test_by_keypress (int sig)
 void
 cut_setup (void)
 {
-  size_t n;
+  size_t n = nfc_list_devices (connstrings, 2);
-
-  nfc_list_devices (connstrings, 2, &n);
   if (n < 2) {
     cut_omit ("At least two NFC devices must be plugged-in to run this test");
   }

test/test_dep_passive.c

@@ -26,9 +26,7 @@ abort_test_by_keypress (int sig)
 void
 cut_setup (void)
 {
-  size_t n;
+  size_t n = nfc_list_devices (connstrings, 2);
-
-  nfc_list_devices (connstrings, 2, &n);
   if (n < 2) {
     cut_omit ("At least two NFC devices must be plugged-in to run this test");
   }

test/test_register_access.c

@@ -10,10 +10,9 @@ void
 test_register_endianness (void)
 {
     nfc_connstring connstrings[MAX_DEVICE_COUNT];
-    size_t device_count;
     int res = 0;
 
-    nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &device_count);
+    size_t device_count = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
     if (!device_count)
 	cut_omit ("No NFC device found");
 

test/test_register_endianness.c

@@ -11,10 +11,9 @@ void
 test_register_endianness (void)
 {
     nfc_connstring connstrings[MAX_DEVICE_COUNT];
-    size_t device_count;
     int res = 0;
 
-    nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &device_count);
+    size_t device_count = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
     if (!device_count)
 	cut_omit ("No NFC device found");
 

utils/nfc-list.c

@@ -114,9 +114,8 @@ main (int argc, const char *argv[])
   strcpy(ndd.acDevice, "SCM Micro / SCL3711-NFC&RW");
   pnd = nfc_connect (&ndd);
 #endif
-  size_t  szDeviceFound;
   nfc_connstring connstrings[MAX_DEVICE_COUNT];
-  nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szDeviceFound);
+  size_t szDeviceFound = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
 
   if (szDeviceFound == 0) {
     printf ("No NFC device found.\n");

utils/nfc-relay-picc.c

@@ -149,7 +149,6 @@ int
 main (int argc, char *argv[])
 {
   int     arg;
-  size_t  szFound;
   const char *acLibnfcVersion = nfc_version ();
   nfc_target ntRealTarget;
 
@@ -193,7 +192,7 @@ main (int argc, char *argv[])
 
   nfc_connstring connstrings[MAX_DEVICE_COUNT];
   // List available devices
-  nfc_list_devices (connstrings, MAX_DEVICE_COUNT, &szFound);
+  size_t szFound = nfc_list_devices (connstrings, MAX_DEVICE_COUNT);
 
   if (initiator_only_mode || target_only_mode) {
     if (szFound < 1) {