1 files changed, 312 insertions, 0 deletions
diff --git a/nuttx/sched/task_setup.c b/nuttx/sched/task_setup.c
new file mode 100644
index 000000000..3573e72d9
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+++ b/nuttx/sched/task_setup.c
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+/************************************************************
+ * task_setup.c
+ *
+ *   Copyright (C) 2007 Gregory Nutt. All rights reserved.
+ *   Author: Gregory Nutt <spudmonkey@racsa.co.cr>
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in
+ *    the documentation and/or other materials provided with the
+ *    distribution.
+ * 3. Neither the name Gregory Nutt nor the names of its contributors may be
+ *    used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
+ * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ ************************************************************/
+
+/************************************************************
+ * Included Files
+ ************************************************************/
+
+#include <nuttx/config.h>
+#include <sys/types.h>
+#include <sched.h>
+#include <string.h>
+#include <errno.h>
+#include <debug.h>
+#include <nuttx/arch.h>
+#include "os_internal.h"
+
+/************************************************************
+ * Definitions
+ ************************************************************/
+
+/************************************************************
+ * Private Type Declarations
+ ************************************************************/
+
+/************************************************************
+ * Global Variables
+ ************************************************************/
+
+/************************************************************
+ * Private Variables
+ ************************************************************/
+
+/* This is the name for un-named tasks */
+
+static FAR char g_noname[] = "no name";
+
+/************************************************************
+ * Private Function Prototypes
+ ************************************************************/
+
+static STATUS   task_assignpid(FAR _TCB* tcb);
+
+/************************************************************
+ * Private Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: task_assignpid
+ *
+ * Description:
+ *   This function assigns the next unique task ID to a task.
+ *
+ * Inputs:
+ *   tcb - TCB of task
+ *
+ * Return:
+ *   OK on success; ERROR on failure (errno is not set)
+ *
+ ************************************************************/
+
+static STATUS task_assignpid(FAR _TCB *tcb)
+{
+  pid_t next_pid;
+  int   hash_ndx;
+  int   tries = 0;
+
+  /* Disable pre-emption.  This should provide sufficient protection
+   * for the following operation.
+   */
+
+  (void)sched_lock();
+
+  /* We'll try every allowable pid */
+
+  for (tries = 0; tries < CONFIG_MAX_TASKS; tries++)
+    {
+      /* Get the next process ID candidate */
+
+      next_pid = ++g_lastpid;
+
+      /* Verify that the next_pid is in the valid range */
+
+      if (next_pid <= 0)
+        {
+          g_lastpid = 1;
+          next_pid  = 1;
+        }
+
+      /* Get the hash_ndx associated with the next_pid */
+
+      hash_ndx = PIDHASH(next_pid);
+
+      /* Check if there is a (potential) duplicate of this pid */
+
+      if (!g_pidhash[hash_ndx].tcb)
+        {
+          g_pidhash[hash_ndx].tcb = tcb;
+          g_pidhash[hash_ndx].pid = next_pid;
+          tcb->pid = next_pid;
+          (void)sched_unlock();
+          return OK;
+        }
+    }
+
+  /* If we get here, then the g_pidhash[] table is completely full.
+   * We cannot allow another task to be started.
+   */
+
+  (void)sched_unlock();
+  return ERROR;
+}
+
+/************************************************************
+ * Public Functions
+ ************************************************************/
+
+/************************************************************
+ * Name: task_schedsetup
+ *
+ * Description:
+ *   This functions initializes a Task Control Block (TCB)
+ *   in preparation for starting a new thread.
+ *
+ *   task_schedsetup() is called from task_init(),
+ *   task_start(), and pthread_create();
+ *
+ * Input Parameters:
+ *   tcb        - Address of the new task's TCB
+ *   priority   - Priority of the new task
+ *   entry      - Entry point of a new task
+ *   main       - Application start point of the new task
+ *
+ * Return Value:
+ *   OK on success; ERROR on failure.
+ *
+ *   This function can only failure is it is unable to assign
+ *   a new, unique task ID to the TCB (errno is not set).
+ *
+ ************************************************************/
+
+STATUS task_schedsetup(FAR _TCB *tcb, int priority,
+                       start_t start, main_t main)
+{
+  STATUS ret;
+
+  /* Assign a unique task ID to the task. */
+
+  ret = task_assignpid(tcb);
+  if (ret == OK)
+    {
+      /* Save task priority and entry point in the TCB */
+
+      tcb->init_priority  = (ubyte)priority;
+      tcb->sched_priority = (ubyte)priority;
+      tcb->start          = start;
+      tcb->entry.main     = main;
+
+      /* Initialize other (non-zero) elements of the TCB */
+
+#ifndef CONFIG_DISABLE_SIGNALS
+      tcb->sigprocmask  = ALL_SIGNAL_SET;
+#endif
+      tcb->task_state   = TSTATE_TASK_INVALID;
+
+      /* Initialize the processor-specific portion of the TCB */
+
+      up_initial_state(tcb);
+
+      /* Add the task to the inactive task list */
+
+      sched_lock();
+      dq_addfirst((FAR dq_entry_t*)tcb, &g_inactivetasks);
+      tcb->task_state = TSTATE_TASK_INACTIVE;
+      sched_unlock();
+    }
+
+  return ret;
+}
+
+/************************************************************
+ * Name: task_argsetup
+ *
+ * Description:
+ *   This functions sets up parameters in the Task Control
+ *   Block (TCB) in preparation for starting a new thread.
+ *
+ *   task_argsetup() is called from task_init() and task_start()
+ *   to create a new task (with arguments cloned via strdup)
+ *   or pthread_create() which has one argument passed by
+ *   value (distinguished by the pthread boolean argument).
+ *
+ * Input Parameters:
+ *   tcb        - Address of the new task's TCB
+ *   name       - Name of the new task (not used)
+ *   pthread    - TRUE is the task emulates pthread behavior
+ *   argv       - A pointer to an array of input parameters.
+ *                Up to CONFIG_MAX_TASK_ARG parameters may be
+ *                provided. If fewer than CONFIG_MAX_TASK_ARG
+ *                parameters are passed, the list should be
+ *                terminated with a NULL argv[] value.
+ *                If no parameters are required, argv may be NULL.
+ *
+ * Return Value:
+ *  OK
+ *
+ ************************************************************/
+
+STATUS task_argsetup(FAR _TCB *tcb, const char *name,
+                     boolean pthread, char *argv[])
+{
+  int i;
+
+#if CONFIG_TASK_NAME_SIZE > 0
+  /* Give a name to the unnamed threads */
+
+  if (!name)
+    {
+      name = g_noname;
+    }
+
+  /* copy the name into the TCB */
+
+  strncpy(tcb->name, name, CONFIG_TASK_NAME_SIZE);
+#endif /* CONFIG_TASK_NAME_SIZE */
+
+  /* Save the arguments in the TCB */
+
+#if CONFIG_TASK_NAME_SIZE > 0
+  tcb->argv[0] = tcb->name;
+#else
+  tcb->argv[0] = g_noname;
+#endif
+
+  /* For pthreads, args are strictly pass-by-value; the char*
+   * arguments wrap some unknown value cast to char*.  However,
+   * for tasks, the life of the argument must be as long as
+   * the life of the task and the arguments must be strings.
+   * So for tasks, we have to to dup the strings.
+   */
+
+  if (!pthread)
+    {
+      /* The first NULL argument terminates the list of 
+       * arguments.  The argv pointer may be NULL if no
+       * parameters are passed.
+       */
+
+      i = 1;
+      if (argv)
+        {
+          for (; i < CONFIG_MAX_TASK_ARGS+1 && argv[i-1]; i++)
+            {
+              tcb->argv[i] = strdup(argv[i-1]);
+            }
+        }
+    }
+  else
+    {
+      /* Mark this task as a pthread */
+
+      tcb->flags   |= TCB_FLAG_PTHREAD;
+
+      /* And just copy the argument. For pthreads, there
+       * is really only a single argument, argv[0].  It is
+       * copy as a value -- NOT duplicated.
+       */
+
+      i = 2;
+      tcb->argv[1]  = argv[0];
+    }
+
+  /* Nullify any unused argument storage */
+
+  for (; i < CONFIG_MAX_TASK_ARGS+1; i++)
+    {
+      tcb->argv[i] = NULL;
+    }
+
+  return OK;
+}