Add a simple task console driver

Close #3320.

1 files changed, 218 insertions, 0 deletions

diff --git a/cpukit/libcsupport/src/consolesimpletask.c b/cpukit/libcsupport/src/consolesimpletask.c
new file mode 100644
index 0000000000..29bab8cb86
--- /dev/null
+++ b/cpukit/libcsupport/src/consolesimpletask.c
@@ -0,0 +1,218 @@
+/*
+ * Copyright (c) 2018 embedded brains GmbH.  All rights reserved.
+ *
+ *  embedded brains GmbH
+ *  Dornierstr. 4
+ *  82178 Puchheim
+ *  Germany
+ *  <rtems@embedded-brains.de>
+ *
+ * The license and distribution terms for this file may be
+ * found in the file LICENSE in this distribution or at
+ * http://www.rtems.org/license/LICENSE.
+ */
+
+#include <rtems/console.h>
+#include <rtems/bspIo.h>
+#include <rtems/imfs.h>
+#include <rtems/thread.h>
+
+#include "consolesimple.h"
+
+#define CONSOLE_SIMPLE_TASK_BUFFER_SIZE 2048
+
+#define CONSOLE_SIMPLE_TASK_MAX_JUNK_SIZE 80
+
+typedef struct {
+  RTEMS_INTERRUPT_LOCK_MEMBER( buf_lock )
+  rtems_mutex output_mutex;
+  rtems_id task;
+  size_t head;
+  size_t tail;
+  char buf[ CONSOLE_SIMPLE_TASK_BUFFER_SIZE ];
+} Console_simple_task_Control;
+
+static Console_simple_task_Control _Console_simple_task_Instance;
+
+static size_t _Console_simple_task_Capacity(
+  const Console_simple_task_Control *cons
+)
+{
+  return ( cons->tail - cons->head - 1 ) % CONSOLE_SIMPLE_TASK_BUFFER_SIZE;
+}
+
+static size_t _Console_simple_task_Available(
+  const Console_simple_task_Control *cons
+)
+{
+  return ( cons->head - cons->tail ) % CONSOLE_SIMPLE_TASK_BUFFER_SIZE;
+}
+
+static ssize_t _Console_simple_task_Write(
+  rtems_libio_t *iop,
+  const void    *buffer,
+  size_t         count
+)
+{
+  Console_simple_task_Control *cons;
+  const char                  *buf;
+  size_t                       todo;
+
+  cons = IMFS_generic_get_context_by_iop( iop );
+  buf = buffer;
+  todo = count;
+
+  while ( todo > 0 ) {
+    rtems_interrupt_lock_context lock_context;
+    size_t                       junk;
+    size_t                       head;
+    size_t                       i;
+
+    rtems_interrupt_lock_acquire( &cons->buf_lock, &lock_context );
+
+    junk = _Console_simple_task_Capacity( cons );
+
+    if ( junk > todo ) {
+      junk = todo;
+    }
+
+    if ( junk > CONSOLE_SIMPLE_TASK_MAX_JUNK_SIZE ) {
+      junk = CONSOLE_SIMPLE_TASK_MAX_JUNK_SIZE;
+    }
+
+    head = cons->head;
+
+    for ( i = 0; i < junk; ++i ) {
+      cons->buf[ head ] = *buf;
+      head = ( head + 1 ) % CONSOLE_SIMPLE_TASK_BUFFER_SIZE;
+      --todo;
+      ++buf;
+    }
+
+    cons->head = head;
+
+    rtems_interrupt_lock_release( &cons->buf_lock, &lock_context );
+
+    if ( junk == 0 ) {
+      break;
+    }
+  }
+
+  rtems_event_system_send( cons->task, RTEMS_EVENT_SYSTEM_SERVER );
+
+  return (ssize_t) ( count - todo );
+}
+
+static void _Console_simple_task_Put_chars( Console_simple_task_Control *cons )
+{
+  rtems_interrupt_lock_context lock_context;
+  size_t                       available;
+  size_t                       tail;
+  size_t                       i;
+
+  rtems_mutex_lock( &cons->output_mutex );
+
+  rtems_interrupt_lock_acquire( &cons->buf_lock, &lock_context );
+
+  available = _Console_simple_task_Available( cons );
+  tail = cons->tail;
+
+  rtems_interrupt_lock_release( &cons->buf_lock, &lock_context );
+
+  for ( i = 0; i < available; ++i) {
+    rtems_putc( cons->buf[ tail ] );
+    tail = ( tail + 1 ) % CONSOLE_SIMPLE_TASK_BUFFER_SIZE;
+  }
+
+  rtems_interrupt_lock_acquire( &cons->buf_lock, &lock_context );
+
+  cons->tail = tail;
+
+  rtems_interrupt_lock_release( &cons->buf_lock, &lock_context );
+
+  rtems_mutex_unlock( &cons->output_mutex );
+}
+
+static int _Console_simple_task_Fsync( rtems_libio_t *iop )
+{
+  Console_simple_task_Control *cons;
+
+  cons = IMFS_generic_get_context_by_iop( iop );
+  _Console_simple_task_Put_chars( cons );
+}
+
+static const rtems_filesystem_file_handlers_r _Console_simple_task_Handlers = {
+  .open_h = rtems_filesystem_default_open,
+  .close_h = rtems_filesystem_default_close,
+  .read_h = _Console_simple_Read,
+  .write_h = _Console_simple_task_Write,
+  .ioctl_h = rtems_filesystem_default_ioctl,
+  .lseek_h = rtems_filesystem_default_lseek,
+  .fstat_h = IMFS_stat,
+  .ftruncate_h = rtems_filesystem_default_ftruncate,
+  .fsync_h = _Console_simple_task_Fsync,
+  .fdatasync_h = _Console_simple_task_Fsync,
+  .fcntl_h = rtems_filesystem_default_fcntl,
+  .readv_h = rtems_filesystem_default_readv,
+  .writev_h = rtems_filesystem_default_writev,
+  .mmap_h = rtems_filesystem_default_mmap
+};
+
+static const IMFS_node_control
+_Console_simple_task_Node_control = IMFS_GENERIC_INITIALIZER(
+  &_Console_simple_task_Handlers,
+  IMFS_node_initialize_generic,
+  IMFS_node_destroy_default
+);
+
+static void _Console_simple_task_Task( rtems_task_argument arg )
+{
+  Console_simple_task_Control *cons;
+
+  cons = (Console_simple_task_Control *) arg;
+
+  while ( true ) {
+    rtems_event_set events;
+
+    rtems_event_system_receive(
+      RTEMS_EVENT_SYSTEM_SERVER,
+      RTEMS_WAIT | RTEMS_EVENT_ALL,
+      RTEMS_NO_TIMEOUT,
+      &events
+    );
+
+    _Console_simple_task_Put_chars( cons );
+  }
+}
+
+void _Console_simple_task_Initialize( void )
+{
+  Console_simple_task_Control *cons;
+
+  cons = &_Console_simple_task_Instance;
+
+  rtems_interrupt_lock_initialize( &cons->buf_lock, "Console" );
+  rtems_mutex_init( &cons->output_mutex, "Console" );
+
+  IMFS_make_generic_node(
+    CONSOLE_DEVICE_NAME,
+    S_IFCHR | S_IRWXU | S_IRWXG | S_IRWXO,
+    &_Console_simple_task_Node_control,
+    cons
+  );
+
+  rtems_task_create(
+    rtems_build_name('C', 'O', 'N', 'S'),
+    RTEMS_MAXIMUM_PRIORITY - 1,
+    RTEMS_MINIMUM_STACK_SIZE,
+    RTEMS_DEFAULT_ATTRIBUTES,
+    RTEMS_DEFAULT_MODES,
+    &cons->task
+  );
+
+  rtems_task_start(
+    cons->task,
+    _Console_simple_task_Task,
+    (rtems_task_argument) cons
+  );
+}