remove spMutex, use atomic test&set instead

client/comms.c

@@ -48,8 +48,6 @@ static int cmd_tail = 0;
 
 // to lock rxBuffer operations from different threads
 static pthread_mutex_t rxBufferMutex = PTHREAD_MUTEX_INITIALIZER;
-// serial port access from different threads
-static pthread_mutex_t spMutex = PTHREAD_MUTEX_INITIALIZER;
 
 // Global start time for WaitForResponseTimeout & dl_it, so we can reset timeout when we get packets
 // as sending lot of these packets can slow down things wuite a lot on slow links (e.g. hw status or lf read at 9600)
@@ -344,8 +342,6 @@ __attribute__((force_align_arg_pointer))
             break;
         }
 
-        pthread_mutex_lock(&spMutex);
-
         res = uart_receive(sp, (uint8_t *)&rx_raw.pre, sizeof(PacketResponseNGPreamble), &rxlen);
         if ((res == PM3_SUCCESS) && (rxlen == sizeof(PacketResponseNGPreamble))) {
             rx.magic = rx_raw.pre.magic;
@@ -465,8 +461,6 @@ __attribute__((force_align_arg_pointer))
             }
         }
 
-        pthread_mutex_unlock(&spMutex);
-
         // TODO if error, shall we resync ?
 
         pthread_mutex_lock(&txBufferMutex);
@@ -486,7 +480,6 @@ __attribute__((force_align_arg_pointer))
 
         if (txBuffer_pending) {
 
-            pthread_mutex_lock(&spMutex);
             if (txBufferNGLen) { // NG packet
                 res = uart_send(sp, (uint8_t *) &txBufferNG, txBufferNGLen);
                 if (res == PM3_EIO) {
@@ -501,7 +494,6 @@ __attribute__((force_align_arg_pointer))
                 }
                 conn.last_command = txBuffer.cmd;
             }
-            pthread_mutex_unlock(&spMutex);
 
             txBuffer_pending = false;
 
@@ -628,13 +620,7 @@ int TestProxmark(void) {
 
             // reconfigure.
             if (conn.send_via_fpc_usart == false) {
-#if defined(_WIN32)
+                int res = uart_reconfigure_timeouts(UART_USB_CLIENT_RX_TIMEOUT_MS);
-                pthread_mutex_lock(&spMutex);
-#endif
-                int res = uart_reconfigure_timeouts(sp, UART_USB_CLIENT_RX_TIMEOUT_MS);
-#if defined(_WIN32)
-                pthread_mutex_unlock(&spMutex);
-#endif
                 if (res != PM3_SUCCESS) {
                     return res;
                 }

uart/uart.h

@@ -107,6 +107,6 @@ uint32_t uart_get_speed(const serial_port sp);
 
 /* Reconfigure timeouts
  */
-int uart_reconfigure_timeouts(serial_port sp, uint32_t value);
+int uart_reconfigure_timeouts(uint32_t value);
 #endif // _UART_H_
 

uart/uart_posix.c

@@ -73,8 +73,12 @@ struct timeval timeout = {
     .tv_usec = UART_FPC_CLIENT_RX_TIMEOUT_MS * 1000
 };
 
-int uart_reconfigure_timeouts(serial_port sp, uint32_t value) {
+uint32_t newtimeout_value = 0;
-    timeout.tv_usec = value * 1000;
+bool newtimeout_nopending = true;
+
+int uart_reconfigure_timeouts(uint32_t value) {
+    newtimeout_value = value;
+    __atomic_clear(&newtimeout_nopending, __ATOMIC_SEQ_CST);
     return PM3_SUCCESS;
 }
 
@@ -83,7 +87,7 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
     if (sp == 0) return INVALID_SERIAL_PORT;
 
     // init timeouts
-    uart_reconfigure_timeouts(sp, UART_FPC_CLIENT_RX_TIMEOUT_MS);
+    timeout.tv_usec = UART_FPC_CLIENT_RX_TIMEOUT_MS * 1000;
 
     if (memcmp(pcPortName, "tcp:", 4) == 0) {
         struct addrinfo *addr, *rp;
@@ -241,7 +245,6 @@ int uart_receive(const serial_port sp, uint8_t *pbtRx, uint32_t pszMaxRxLen, uin
 
     // Reset the output count
     *pszRxLen = 0;
-
     do {
         // Reset file descriptor
         FD_ZERO(&rfds);
@@ -299,6 +302,8 @@ int uart_send(const serial_port sp, const uint8_t *pbtTx, const uint32_t len) {
     uint32_t pos = 0;
     fd_set rfds;
     struct timeval tv;
+    if (__atomic_test_and_set(&newtimeout_nopending, __ATOMIC_SEQ_CST) == 0)
+        timeout.tv_usec = newtimeout_value * 1000;
 
     while (pos < len) {
         // Reset file descriptor

uart/uart_win32.c

@@ -48,7 +48,19 @@ typedef struct {
     COMMTIMEOUTS ct;  // Serial port time-out configuration
 } serial_port_windows;
 
-int uart_reconfigure_timeouts(serial_port sp, uint32_t value) {
+uint32_t newtimeout_value = 0;
+bool newtimeout_nopending = true;
+
+int uart_reconfigure_timeouts(uint32_t value) {
+    newtimeout_value = value;
+    __atomic_clear(&newtimeout_nopending, __ATOMIC_SEQ_CST);
+    return PM3_SUCCESS;
+}
+
+static int uart_reconfigure_timeouts_polling(serial_port sp) {
+    if (__atomic_test_and_set(&newtimeout_nopending, __ATOMIC_SEQ_CST) != 0)
+        return PM3_SUCCESS;
+
     serial_port_windows *spw;
     spw = (serial_port_windows *)sp;
     spw->ct.ReadIntervalTimeout         = value;
@@ -103,7 +115,8 @@ serial_port uart_open(const char *pcPortName, uint32_t speed) {
         return INVALID_SERIAL_PORT;
     }
 
-    uart_reconfigure_timeouts(sp, UART_FPC_CLIENT_RX_TIMEOUT_MS);
+    uart_reconfigure_timeouts(UART_FPC_CLIENT_RX_TIMEOUT_MS);
+    uart_reconfigure_timeouts_polling(sp);
 
     if (!uart_set_speed(sp, speed)) {
         // try fallback automatically
@@ -176,6 +189,7 @@ int uart_receive(const serial_port sp, uint8_t *pbtRx, uint32_t pszMaxRxLen, uin
 }
 
 int uart_send(const serial_port sp, const uint8_t *p_tx, const uint32_t len) {
+    uart_reconfigure_timeouts_polling(sp);
     DWORD txlen = 0;
     int res = WriteFile(((serial_port_windows *)sp)->hPort, p_tx, len, &txlen, NULL);
     if (res)