replace msleep() by thread signalling in comms.c

diff --git a/client/comms.c b/client/comms.c
index 716a163df24a1f1aeeb0c7492665cf7e89685e73..c8d72b8a5cf036eb733231716fbb71324fc3de0e 100644 (file)
--- a/client/comms.c
+++ b/client/comms.c
@@ -16,6 +16,7 @@
 #include <string.h>
 #include <pthread.h>
 #include <inttypes.h>
+#include <time.h>
 
 #include "uart.h"
 #include "ui.h"
@@ -57,6 +58,7 @@ static int cmd_tail = 0;
 
 // to lock rxBuffer operations from different threads
 static pthread_mutex_t rxBufferMutex = PTHREAD_MUTEX_INITIALIZER;
+static pthread_cond_t rxBufferSig = PTHREAD_COND_INITIALIZER;
 
 // These wrappers are required because it is not possible to access a static
 // global variable outside of the context of a single file.
@@ -127,6 +129,7 @@ static void storeCommand(UsbCommand *command) {
        memcpy(destination, command, sizeof(UsbCommand));
 
        cmd_head = (cmd_head + 1) % CMD_BUFFER_SIZE; //increment head and wrap
+       pthread_cond_signal(&rxBufferSig); // tell main thread that a new command can be retreived
        pthread_mutex_unlock(&rxBufferMutex);
 }
 
@@ -134,12 +137,24 @@ static void storeCommand(UsbCommand *command) {
 /**
  * @brief getCommand gets a command from an internal circular buffer.
  * @param response location to write command
- * @return 1 if response was returned, 0 if nothing has been received
+ * @return 1 if response was returned, 0 if nothing has been received in time
  */
-static int getCommand(UsbCommand* response) {
+static int getCommand(UsbCommand* response, uint32_t ms_timeout) {
+
+       struct timespec end_time;
+       clock_gettime(CLOCK_REALTIME, &end_time);
+       end_time.tv_sec += ms_timeout / 1000;
+       end_time.tv_nsec += (ms_timeout % 1000) * 1000000;
+       if (end_time.tv_nsec > 1000000000) {
+               end_time.tv_nsec -= 1000000000;
+               end_time.tv_sec += 1;
+       }
        pthread_mutex_lock(&rxBufferMutex);
-       // If head == tail, there's nothing to read
-       if (cmd_head == cmd_tail) {
+       int res = 0;
+       while (cmd_head == cmd_tail && !res) {
+               res = pthread_cond_timedwait(&rxBufferSig, &rxBufferMutex, &end_time);
+       }
+       if (res) { // timeout
                pthread_mutex_unlock(&rxBufferMutex);
                return 0;
        }
@@ -187,7 +202,7 @@ static void UsbCommandReceived(UsbCommand *UC) {
 static bool receive_from_serial(serial_port sp, uint8_t *rx_buf, size_t len, size_t *received_len) {
        size_t bytes_read = 0;
        *received_len = 0;
-       // we eventually need to call uart_receive several times if it times out in the middle of a transfer
+       // we eventually need to call uart_receive several times because it may timeout in the middle of a transfer
        while (uart_receive(sp, rx_buf + *received_len, len - *received_len, &bytes_read) && bytes_read && *received_len < len) {
                #ifdef COMMS_DEBUG
                if (bytes_read != len - *received_len) {
@@ -299,10 +314,12 @@ __attribute__((force_align_arg_pointer))
  * @return true if command was returned, otherwise false
  */
 bool GetFromBigBuf(uint8_t *dest, int bytes, int start_index, UsbCommand *response, size_t ms_timeout, bool show_warning) {
-       UsbCommand c = {CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K, {start_index, bytes, 0}};
-       SendCommand(&c);
 
        uint64_t start_time = msclock();
+       uint32_t poll_time = 100; // loop every 100ms
+
+       UsbCommand c = {CMD_DOWNLOAD_RAW_ADC_SAMPLES_125K, {start_index, bytes, 0}};
+       SendCommand(&c);
 
        UsbCommand resp;
        if (response == NULL) {
@@ -311,7 +328,16 @@ bool GetFromBigBuf(uint8_t *dest, int bytes, int start_index, UsbCommand *respon
 
        int bytes_completed = 0;
        while (true) {
-               if (getCommand(response)) {
+               if (msclock() - start_time > ms_timeout) {
+                       break; // timeout
+               }
+               if (msclock() - start_time > 2000 && show_warning) {
+                       // 2 seconds elapsed (but this doesn't mean the timeout was exceeded)
+                       PrintAndLog("Waiting for a response from the proxmark...");
+                       PrintAndLog("You can cancel this operation by pressing the pm3 button");
+                       show_warning = false;
+               }
+               if (getCommand(response, poll_time)) {
                        if (response->cmd == CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K) {
                                int copy_bytes = MIN(bytes - bytes_completed, response->arg[1]);
                                memcpy(dest + response->arg[0], response->d.asBytes, copy_bytes);
@@ -320,16 +346,6 @@ bool GetFromBigBuf(uint8_t *dest, int bytes, int start_index, UsbCommand *respon
                                return true;
                        }
                }
-
-               if (msclock() - start_time > ms_timeout) {
-                       break;
-               }
-
-               if (msclock() - start_time > 2000 && show_warning) {
-                       PrintAndLog("Waiting for a response from the proxmark...");
-                       PrintAndLog("You can cancel this operation by pressing the pm3 button");
-                       show_warning = false;
-               }
        }
 
        return false;
@@ -337,17 +353,24 @@ bool GetFromBigBuf(uint8_t *dest, int bytes, int start_index, UsbCommand *respon
 
 
 bool GetFromFpgaRAM(uint8_t *dest, int bytes) {
-       UsbCommand c = {CMD_HF_PLOT, {0, 0, 0}};
-       SendCommand(&c);
 
        uint64_t start_time = msclock();
+       uint32_t poll_time = 100; // loop every 100ms
+
+       UsbCommand c = {CMD_HF_PLOT, {0, 0, 0}};
+       SendCommand(&c);
 
        UsbCommand response;
 
        int bytes_completed = 0;
        bool show_warning = true;
        while (true) {
-               if (getCommand(&response)) {
+               if (msclock() - start_time > 2000 && show_warning) {
+                       PrintAndLog("Waiting for a response from the proxmark...");
+                       PrintAndLog("You can cancel this operation by pressing the pm3 button");
+                       show_warning = false;
+               }
+               if (getCommand(&response, poll_time)) {
                        if (response.cmd == CMD_DOWNLOADED_RAW_ADC_SAMPLES_125K) {
                                int copy_bytes = MIN(bytes - bytes_completed, response.arg[1]);
                                memcpy(dest + response.arg[0], response.d.asBytes, copy_bytes);
@@ -356,12 +379,6 @@ bool GetFromFpgaRAM(uint8_t *dest, int bytes) {
                                return true;
                        }
                }
-
-               if (msclock() - start_time > 2000 && show_warning) {
-                       PrintAndLog("Waiting for a response from the proxmark...");
-                       PrintAndLog("You can cancel this operation by pressing the pm3 button");
-                       show_warning = false;
-               }
        }
 
        return false;
@@ -454,31 +471,30 @@ bool WaitForResponseTimeoutW(uint32_t cmd, UsbCommand* response, size_t ms_timeo
        printf("Waiting for %04x cmd\n", cmd);
        #endif
 
+       uint64_t start_time = msclock();
+       uint64_t end_time = start_time + ms_timeout;
+
        if (response == NULL) {
                response = &resp;
        }
 
-       uint64_t start_time = msclock();
-
        // Wait until the command is received
        while (true) {
-               while (getCommand(response)) {
-                       if (cmd == CMD_UNKNOWN || response->cmd == cmd) {
-                               return true;
-                       }
-               }
-
-               if (msclock() - start_time > ms_timeout) {
-                       break;
+               int32_t remaining_time = end_time - msclock();
+               if (remaining_time <= 0) {
+                       break; // timeout
                }
-
                if (msclock() - start_time > 2000 && show_warning) {
                        // 2 seconds elapsed (but this doesn't mean the timeout was exceeded)
                        PrintAndLog("Waiting for a response from the proxmark...");
                        PrintAndLog("You can cancel this operation by pressing the pm3 button");
                        show_warning = false;
                }
-               msleep(1);
+               if (getCommand(response, remaining_time)) {
+                       if (cmd == CMD_UNKNOWN || response->cmd == cmd) {
+                               return true;
+                       }
+               }
        }
        return false;
 }