examples: make main loops finite to ensure proper cleanup

Signed-off-by: Alex Tereschenko <alext.mkrs@gmail.com>
Signed-off-by: Brendan Le Foll <brendan.le.foll@intel.com>

examples/analogin_a0.c

@@ -1,5 +1,6 @@
 /*
  * Author: Nandkishor Sonar
+ * Contributors: Alex Tereschenko <alext.mkrs@gmail.com>
  * Copyright (c) 2014 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -23,30 +24,49 @@
  */
 
 #include <unistd.h>
-//! [Interesting]
+#include <signal.h>
+
 #include "mraa/aio.h"
 
+int running = 0;
+
+void
+sig_handler(int signo)
+{
+    if (signo == SIGINT) {
+        printf("closing down nicely\n");
+        running = -1;
+    }
+}
+
+//! [Interesting]
 int
 main()
 {
     mraa_aio_context adc_a0;
     uint16_t adc_value = 0;
     float adc_value_float = 0.0;
+    mraa_result_t r = MRAA_SUCCESS;
 
     adc_a0 = mraa_aio_init(0);
     if (adc_a0 == NULL) {
         return 1;
     }
 
-    for (;;) {
+    signal(SIGINT, sig_handler);
+
+    while (running == 0) {
         adc_value = mraa_aio_read(adc_a0);
         adc_value_float = mraa_aio_read_float(adc_a0);
         fprintf(stdout, "ADC A0 read %X - %d\n", adc_value, adc_value);
-        fprintf(stdout, "ADC A0 read float - %.5f\n", adc_value_float);
+        fprintf(stdout, "ADC A0 read float - %.5f (Ctrl+C to exit)\n", adc_value_float);
     }
 
-    mraa_aio_close(adc_a0);
+    r = mraa_aio_close(adc_a0);
+    if (r != MRAA_SUCCESS) {
+        mraa_result_print(r);
+    }
 
-    return MRAA_SUCCESS;
+    return r;
 }
 //! [Interesting]

examples/blink_onboard.c

@@ -1,5 +1,6 @@
 /*
  * Author: Brendan Le Foll <brendan.le.foll@intel.com>
+ * Contributors: Alex Tereschenko <alext.mkrs@gmail.com>
  * Copyright (c) 2014 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -25,9 +26,21 @@
 #include <stdio.h>
 #include <string.h>
 #include <unistd.h>
+#include <signal.h>
 
 #include "mraa/gpio.h"
 
+int running = 0;
+
+void
+sig_handler(int signo)
+{
+    if (signo == SIGINT) {
+        printf("closing down nicely\n");
+        running = -1;
+    }
+}
+
 int
 main(int argc, char** argv)
 {
@@ -35,6 +48,7 @@ main(int argc, char** argv)
     mraa_gpio_context gpio, gpio_in = NULL;
     const char* board_name = mraa_get_platform_name();
     int ledstate = 0;
+    mraa_result_t r = MRAA_SUCCESS;
 
     switch (platform) {
         case MRAA_INTEL_GALILEO_GEN1:
@@ -53,7 +67,7 @@ main(int argc, char** argv)
             gpio = mraa_gpio_init(13);
     }
 
-    fprintf(stdout, "Welcome to libmraa\n Version: %s\n Running on %s\n", mraa_get_version(), board_name);
+    fprintf(stdout, "Welcome to libmraa\n Version: %s\n Running on %s (Ctrl+C to exit)\n", mraa_get_version(), board_name);
 
 
     if (gpio == NULL) {
@@ -73,8 +87,11 @@ main(int argc, char** argv)
 
     mraa_gpio_dir(gpio, MRAA_GPIO_OUT);
 
-    for (;;) {
+    signal(SIGINT, sig_handler);
+
+    while (running == 0) {
         if (gpio_in != NULL && mraa_gpio_read(gpio_in) == 0) {
+            mraa_gpio_close(gpio_in);
             return 0;
         }
         ledstate = !ledstate;
@@ -82,5 +99,10 @@ main(int argc, char** argv)
         sleep(1);
     }
 
-    return 0;
+    r = mraa_gpio_close(gpio);
+    if (r != MRAA_SUCCESS) {
+        mraa_result_print(r);
+    }
+
+    return r;
 }

examples/c++/AioA0.cpp

@@ -1,5 +1,6 @@
 /*
  * Author: Brendan Le Foll <brendan.le.foll@intel.com>
+ * Contributors: Alex Tereschenko <alex.mkrs@gmail.com>
  * Copyright (c) 2014 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -22,9 +23,22 @@
  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  */
 
-//! [Interesting]
+#include <signal.h>
+
 #include "mraa.hpp"
 
+int running = 0;
+
+void
+sig_handler(int signo)
+{
+    if (signo == SIGINT) {
+        printf("closing down nicely\n");
+        running = -1;
+    }
+}
+
+//! [Interesting]
 int
 main()
 {
@@ -34,13 +48,16 @@ main()
 
     a0 = new mraa::Aio(0);
 
-    for (;;) {
+    signal(SIGINT, sig_handler);
+
+    while (running == 0) {
         adc_value = a0->read();
         adc_value_float = a0->readFloat();
         fprintf(stdout, "ADC A0 read %X - %d\n", adc_value, adc_value);
-        fprintf(stdout, "ADC A0 read float - %.5f\n", adc_value_float);
+        fprintf(stdout, "ADC A0 read float - %.5f (Ctrl+C to exit)\n", adc_value_float);
     }
 
+    delete a0;
     return MRAA_SUCCESS;
 }
 //! [Interesting]

examples/c++/Isr-pin6.cpp

@@ -1,5 +1,6 @@
 /*
  * Author: Brendan Le Foll
+ * Contributors: Alex Tereschenko <alext.mkrs@gmail.com>
  * Copyright (c) 2015 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -44,7 +45,8 @@ main()
 
     x->isr(mraa::EDGE_BOTH, &interrupt, NULL);
 
-    for (;;) {
+    int i = 100;
+    for (; i > 0; --i) {
         if (counter != oldcounter) {
             fprintf(stdout, "timeout counter == %d\n", counter);
             oldcounter = counter;
@@ -54,5 +56,5 @@ main()
     }
 
     delete x;
-    return EXIT_SUCCESS;
+    return MRAA_SUCCESS;
 }

examples/gpio_read6.c

@@ -1,5 +1,6 @@
 /*
  * Author: Thomas Ingleby <thomas.c.ingleby@intel.com>
+ * Contributors: Alex Tereschenko <alext.mkrs@gmail.com>
  * Copyright (c) 2014 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -24,14 +25,28 @@
 
 #include "stdio.h"
 #include "unistd.h"
+#include <signal.h>
 
 #include "mraa.h"
 
+int running = 0;
+
+void
+sig_handler(int signo)
+{
+    if (signo == SIGINT) {
+        printf("closing down nicely\n");
+        running = -1;
+    }
+}
+
 int
 main(int argc, char** argv)
 {
+    mraa_result_t r = MRAA_SUCCESS;
+
     mraa_init();
-    fprintf(stdout, "MRAA Version: %s\nStarting Read on IO6\n", mraa_get_version());
+    fprintf(stdout, "MRAA Version: %s\nStarting Read on IO6 (Ctrl+C to exit)\n", mraa_get_version());
 
     //! [Interesting]
     mraa_gpio_context gpio;
@@ -40,13 +55,18 @@ main(int argc, char** argv)
 
     mraa_gpio_dir(gpio, MRAA_GPIO_IN);
 
-    for (;;) {
+    signal(SIGINT, sig_handler);
+
+    while (running == 0) {
         fprintf(stdout, "Gpio is %d\n", mraa_gpio_read(gpio));
         sleep(1);
     }
 
-    mraa_gpio_close(gpio);
+    r = mraa_gpio_close(gpio);
     //! [Interesting]
+    if (r != MRAA_SUCCESS) {
+        mraa_result_print(r);
+    }
 
-    return 0;
+    return r;
 }

examples/isr_pin6.c

@@ -1,5 +1,6 @@
 /*
  * Author: Brendan Le Foll
+ * Contributors: Alex Tereschenko <alext.mkrs@gmail.com>
  * Copyright (c) 2014 Intel Corporation.
  *
  * Permission is hereby granted, free of charge, to any person obtaining
@@ -52,7 +53,8 @@ main()
 
     mraa_gpio_isr(x, edge, &interrupt, NULL);
 
-    for (;;) {
+    int i = 100;
+    for (; i > 0; --i) {
         if (counter != oldcounter) {
             fprintf(stdout, "timeout counter == %d\n", counter);
             oldcounter = counter;

examples/java/AioA0.java

@@ -44,11 +44,12 @@ public class AioA0 {
     public static void main(String[] args) {
         Aio a0 = new Aio(0);
 
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             int adc_value = a0.read();
             float adc_value_float = a0.readFloat();
             System.out.println(String.format("ADC A0 read %X - %d", adc_value, adc_value));
             System.out.println(String.format("ADC A0 read %.5f", adc_value_float));
+            Thread.sleep(500);
         }
 
     }

examples/java/BlinkIO.java

@@ -61,7 +61,7 @@ public class BlinkIO {
             System.exit(1);
         }
 
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             gpio.write(1);
             Thread.sleep(1000);
             gpio.write(0);

examples/java/BlinkOnboard.java

@@ -64,7 +64,7 @@ public class BlinkOnboard {
         }
 
         boolean state = false;
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             if (gpio_in != null && gpio_in.read() == 0) {
                 return;
             }

examples/java/CyclePwm3.java

@@ -44,7 +44,7 @@ public class CyclePwm3 {
         pwm.enable(true);
 
         float value = 0;
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             value += 0.01;
             pwm.write(value);
             Thread.sleep(50);

examples/java/FTDITest.java

@@ -50,8 +50,8 @@ public class FTDITest {
             /* Blink FTDI board LED */
             Gpio led = new Gpio(514);
             led.dir(Dir.DIR_OUT);
-            for (int i = 0;; i = (i + 1) % 2) {
+            for (int i = 100; i > 0; --i) {
-                led.write(i);
+                led.write(i % 2);
                 Thread.sleep(500);
             }
         } else {

examples/java/GpioMmapped.java

@@ -50,7 +50,7 @@ public class GpioMmapped {
     
     gpio.useMmap(true);
     
-    while (true) {
+    for (int i = 1000; i > 0; --i) {
         gpio.write(1);
         Thread.sleep(50);
         gpio.write(0);

examples/java/GpioRead6.java

@@ -46,7 +46,7 @@ public class GpioRead6 {
 
         gpio.dir(Dir.DIR_IN);
 
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             System.out.format("Gpio is %d\n", gpio.read());
             Thread.sleep(1000);
         }

examples/java/I2cCompass.java

@@ -110,7 +110,7 @@ public class I2cCompass {
         conf_buf[1] = HMC5883L_CONT_MODE;
         i2c.write(conf_buf);
 
-        while (true) {
+        for (int i = 100; i > 0; --i) {
             i2c.address(HMC5883L_I2C_ADDR);
             i2c.writeByte(HMC5883L_DATA_REG);
 

examples/java/SpiMCP4261.java

@@ -43,7 +43,7 @@ public class SpiMCP4261 {
 
         System.out.println("Hello, SPI initialised");
         byte data[] = {0x00, 100};
-        while (true) {
+        for (int cnt = 100; cnt > 0; --cnt) {
             for (int i = 90; i < 130; i++) {
                 data[1] = (byte) i;
                 byte[] recv = spi.write(data);