1 files changed, 171 insertions, 0 deletions
diff --git a/demos/various/RT-Win32-TriBuf/main.c b/demos/various/RT-Win32-TriBuf/main.c
new file mode 100644
index 0000000..bab25cd
--- /dev/null
+++ b/demos/various/RT-Win32-TriBuf/main.c
@@ -0,0 +1,171 @@
+/*
+    Copyright (C) 2015 Andrea Zoppi
+
+    Licensed under the Apache License, Version 2.0 (the "License");
+    you may not use this file except in compliance with the License.
+    You may obtain a copy of the License at
+
+        http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+#include "ch.h"
+#include "hal.h"
+#include "tribuf.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+
+/*===========================================================================*/
+/* TriBuf related.                                                           */
+/*===========================================================================*/
+
+#define WRITER_DELAY_MS        10
+#define READER_DELAY_MS        20
+
+#define WRITER_STACK_SIZE   4096
+#define READER_STACK_SIZE   4096
+
+#define WRITER_PRIORITY     (NORMALPRIO + 1)
+#define READER_PRIORITY     (NORMALPRIO + 2)
+
+static thread_t *writertp;
+static thread_t *readertp;
+
+static tribuf_t tribuf;
+static char buffers[3];
+
+static const char text[] = "ABCDEFGHIJKLMNOPQRSTUVWXYZ\r\n";
+
+/*
+ * Reads from the front buffer.
+ */
+static char read_front(void) {
+
+  const char *front;
+  msg_t error;
+
+  /* Wait until a new front buffer gets available with prepared data */
+  error = tribufWaitReadyTimeout(&tribuf, MS2ST(1000));
+  if (error == MSG_TIMEOUT)
+    chSysHalt("ERROR: read_front() timed out");
+
+  /* Retrieve the new front buffer */
+  tribufSwapFront(&tribuf);
+  front = (const char *)tribufGetFront(&tribuf);
+
+  /* Read data from the new front buffer */
+  return front[0];
+}
+
+/*
+ * Overwrites the back buffer with the provided character.
+ */
+static void write_back(char c) {
+
+  char *back;
+
+  /* Retrieve the current back buffer */
+  back = (char *)tribufGetBack(&tribuf);
+
+  /* Prepare data onto the current back buffer */
+  back[0] = c;
+
+  /* Exchange the prepared buffer with a new one */
+  tribufSwapBack(&tribuf);
+}
+
+/*
+ * Overwrites the back buffer with a fixed text, character by character.
+ */
+static THD_WORKING_AREA(writer_wa, WRITER_STACK_SIZE);
+static THD_FUNCTION(writer_thread, arg) {
+
+  const uint32_t delay = (uint32_t)(msg_t)arg;
+  size_t i;
+  char c;
+
+  chRegSetThreadName("writer_thread");
+  for (;;) {
+    for (i = 0; i < sizeof(text); ++i) {
+      c = text[i];
+      write_back(c);
+      chThdSleepMilliseconds(delay);
+    }
+  }
+}
+
+/*
+ * Reads the front buffer and prints it.
+ */
+static THD_WORKING_AREA(reader_wa, READER_STACK_SIZE);
+static THD_FUNCTION(reader_thread, arg) {
+
+  const uint32_t delay = (uint32_t)(msg_t)arg;
+  char c;
+
+  chRegSetThreadName("reader_thread");
+  for (;;) {
+    c = read_front();
+    fprintf(stdout, "%c", c);
+    chThdSleepMilliseconds(delay);
+  }
+}
+
+/*===========================================================================*/
+/* Initialization and main thread.                                           */
+/*===========================================================================*/
+
+/*
+ * Simulator main.
+ */
+int main(void) {
+
+  /*
+   * System initializations.
+   * - HAL initialization, this also initializes the configured device drivers
+   *   and performs the board-specific initializations.
+   * - Kernel initialization, the main() function becomes a thread and the
+   *   RTOS is active.
+   */
+  halInit();
+  chSysInit();
+
+  /*
+   * Writer and reader threads started for triple buffer demo.
+   */
+  tribufObjectInit(&tribuf, &buffers[0], &buffers[1], &buffers[2]);
+
+  readertp = chThdCreateStatic(reader_wa, sizeof(reader_wa),
+                               READER_PRIORITY,
+                               reader_thread, (void *)READER_DELAY_MS);
+
+  writertp = chThdCreateStatic(writer_wa, sizeof(writer_wa),
+                               WRITER_PRIORITY,
+                               writer_thread, (void *)WRITER_DELAY_MS);
+
+  /*
+   * Let the threads process data.
+   */
+  for (;;)
+    chThdSleepMilliseconds(1000);
+
+  return 0;
+}
+
+/*
+ * Critical error function.
+ */
+void halt(const char *reason) {
+
+  fflush(stdout);
+  fputs("\n", stdout);
+  fputs(reason, stderr);
+  fflush(stderr);
+  exit(1);
+}