Completes VFS-based named semaphore implemetation. Still a little buggy

fs/binfs/Make.defs

@@ -43,6 +43,5 @@ CSRCS += fs_binfs.c
 
 DEPPATH += --dep-path binfs
 VPATH += :binfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)binfs}
 
 endif

fs/dirent/Make.defs

@@ -43,5 +43,4 @@ CSRCS += fs_closedir.c fs_opendir.c fs_readdir.c fs_rewinddir.c fs_seekdir.c
 
 DEPPATH += --dep-path dirent
 VPATH += :dirent
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)dirent}
 endif

fs/driver/Make.defs

@@ -53,5 +53,4 @@ endif
 
 DEPPATH += --dep-path driver
 VPATH += :driver
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)driver}
 endif

fs/fat/Make.defs

@@ -48,6 +48,5 @@ CSRCS += fs_mkfatfs.c fs_configfat.c fs_writefat.c
 
 DEPPATH += --dep-path fat
 VPATH += :fat
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)fat}
 
 endif

fs/inode/Make.defs

@@ -45,5 +45,4 @@ CSRCS += fs_inoderemove.c fs_inodereserve.c
 
 DEPPATH += --dep-path inode
 VPATH += :inode
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)inode}
 endif

fs/mmap/Make.defs

@@ -44,5 +44,4 @@ endif
 
 DEPPATH += --dep-path mmap
 VPATH += :mmap
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)mmap}
 

fs/mount/Make.defs

@@ -48,6 +48,5 @@ endif
 
 DEPPATH += --dep-path mount
 VPATH += :mount
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)mount}
 endif
 endif

fs/nfs/Make.defs

@@ -48,6 +48,5 @@ CSRCS += rpc_clnt.c nfs_util.c nfs_vfsops.c
 
 DEPPATH += --dep-path nfs
 VPATH += :nfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)nfs}
 
 endif

fs/nxffs/Make.defs

@@ -44,6 +44,5 @@ CSRCS += nxffs_block.c nxffs_blockstats.c nxffs_cache.c nxffs_dirent.c \
 
 DEPPATH += --dep-path nxffs
 VPATH += :nxffs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)nxffs}
 
 endif

fs/procfs/Make.defs

@@ -44,6 +44,5 @@ CSRCS += fs_procfscpuload.c
 
 DEPPATH += --dep-path procfs
 VPATH += :procfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)procfs}
 
 endif

fs/romfs/Make.defs

@@ -43,6 +43,5 @@ CSRCS += fs_romfs.c fs_romfsutil.c
 
 DEPPATH += --dep-path romfs
 VPATH += :romfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)romfs}
 
 endif

fs/semaphore/Make.defs

@@ -37,11 +37,10 @@
 
 ifneq ($(CONFIG_FS_NAMED_SEMAPHORES),0)
 
-CSRCS += sem_open.c
+CSRCS += sem_open.c sem_close.c sem_unlink.c
 
 # Include named semaphore build support
 
 DEPPATH += --dep-path semaphore
 VPATH += :semaphore
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)semaphore}
 endif

fs/semaphore/sem_close.c

@@ -1,7 +1,7 @@
 /****************************************************************************
- * sched/semaphore/sem_close.c
+ * fs/semaphore/sem_close.c
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -39,16 +39,20 @@
 
 #include <nuttx/config.h>
 
-#include <errno.h>
 #include <semaphore.h>
 #include <sched.h>
+#include <errno.h>
 
 #include <nuttx/kmalloc.h>
+#include <nuttx/semaphore.h>
+#include <nuttx/fs/fs.h>
 
-#include "semaphore/semaphore.h"
+#include "fs.h"
+
+#ifdef CONFIG_FS_NAMED_SEMAPHORES
 
 /****************************************************************************
- * Definitions
+ * Pre-processor Definitions
  ****************************************************************************/
 
 /****************************************************************************
@@ -99,43 +103,47 @@
 
 int sem_close(FAR sem_t *sem)
 {
-  FAR nsem_t *psem;
+  FAR struct nsem_inode_s *nsem;
-  int ret = ERROR;
+  struct inode *inode ;
 
-  /* Verify the inputs */
+  DEBUGASSERT(sem);
 
-  if (sem)
+  /* Upcast to get back to out internal representation */
+
+  nsem = (FAR struct nsem_inode_s *)sem;
+  DEBUGASSERT(nsem->ns_inode);
+  inode = nsem->ns_inode;
+
+  /* Decrement the reference count on the inode */
+
+  inode_semtake();
+  if (inode->i_crefs)
     {
-      sched_lock();
+      inode->i_crefs--;
-
-      /* Search the list of named semaphores */
-
-      for (psem = (FAR nsem_t*)g_nsems.head;
-           ((psem) && (sem != &psem->sem));
-           psem = psem->flink);
-
-      /* Check if we found it */
-
-      if (psem)
-        {
-          /* Decrement the count of sem_open connections to this semaphore */
-
-          if (psem->nconnect) psem->nconnect--;
-
-          /* If the semaphore is no long connected to any processes AND the
-           * semaphore was previously unlinked, then deallocate it.
-           */
-
-          if (!psem->nconnect && psem->unlinked)
-            {
-              dq_rem((FAR dq_entry_t*)psem, &g_nsems);
-              sched_kfree(psem);
-            }
-          ret = OK;
-        }
-
-      sched_unlock();
     }
 
-  return ret;
+  /* If the semaphore was previously unlinked and the reference count has
+   * decremented to zero, then release the semaphore and delete the inode
+   * now.
+   */
+
+   if (inode->i_crefs <= 0 && (inode->i_flags & FSNODEFLAG_DELETED) != 0)
+     {
+       /* Destroy the semaphore and free the container */
+
+       sem_destroy(&nsem->ns_sem);
+       group_free(NULL, nsem);
+
+       /* Release and free the inode */
+
+       inode_semgive();
+       inode_free(inode->i_child);
+       kmm_free(inode);
+       return OK;
+     }
+
+  inode_semgive();
+  return OK;
 }
+
+#endif /* CONFIG_FS_NAMED_SEMAPHORES */

fs/semaphore/sem_open.c

@@ -53,6 +53,7 @@
 #include <nuttx/fs/fs.h>
 
 #include "fs.h"
+#include "semaphore/semaphore.h"
 
 #ifdef CONFIG_FS_NAMED_SEMAPHORES
 
@@ -60,8 +61,6 @@
  * Pre-processor Definitions
  ****************************************************************************/
 
-#define MAX_SEMPATH 64
-
 /****************************************************************************
  * Private Type Declarations
  ****************************************************************************/
@@ -122,7 +121,6 @@
 
 FAR sem_t *sem_open (FAR const char *name, int oflags, ...)
 {
-  FAR struct filelist *list;
   FAR struct inode *inode;
   FAR const char *relpath = NULL;
   mode_t mode;
@@ -150,12 +148,7 @@ FAR sem_t *sem_open (FAR const char *name, int oflags, ...)
 
       snprintf(fullpath, MAX_SEMPATH, CONFIG_FS_NAMED_SEMPATH "/%s", name);
 
-      /* Get the thread-specific file list */
+      /* Get the inode for this semaphore.  This should succeed if the semaphore
-
-      list = sched_getfiles();
-      DEBUGASSERT(list);
-
-      /* Get the inode for this file.  This should succeed if the semaphore
        * has already been created.
        */
 
@@ -180,11 +173,11 @@ FAR sem_t *sem_open (FAR const char *name, int oflags, ...)
               goto errout_with_inode;
             }
 
-          /* Allow a new connection to the semaphore */
+          /* Return a reference to the semaphore, retaining the reference
+           * count on the inode.
+           */
 
-          nsem = inode->u.i_nsem;
+          sem = &inode->u.i_nsem->ns_sem;
-          nsem->ns_refs++;
-          sem  = &nsem->ns_sem;
 
         }
       else
@@ -244,11 +237,23 @@ FAR sem_t *sem_open (FAR const char *name, int oflags, ...)
               goto errout_with_lock;
             }
 
-          /* Initialize the semaphore */
+          /* Link to the inode */
 
           inode->u.i_nsem = nsem;
-          nsem->ns_refs   = 1;
+          nsem->ns_inode  = inode;
-          sem             = &nsem->ns_sem;
+
+          /* Initialize the inode */
+
+          INODE_SET_NAMEDSEM(inode);
+          inode->i_crefs = 1;
+
+          /* Initialize the semaphore */
+
+          sem_init(&nsem->ns_sem, 0, value);
+
+          /* Return a reference to the semaphore */
+
+          sem = &nsem->ns_sem;
         }
     }
 

fs/semaphore/sem_unlink.c

@@ -1,7 +1,7 @@
 /****************************************************************************
- * sched/semaphore/sem_unlink.c
+ * fs/semaphore/sem_unlink.c
  *
- *   Copyright (C) 2007-2009 Gregory Nutt. All rights reserved.
+ *   Copyright (C) 2007-2009, 2014 Gregory Nutt. All rights reserved.
  *   Author: Gregory Nutt <gnutt@nuttx.org>
  *
  * Redistribution and use in source and binary forms, with or without
@@ -39,13 +39,15 @@
 
 #include <nuttx/config.h>
 
-#include <stdbool.h>
+#include <stdio.h>
 #include <semaphore.h>
 #include <sched.h>
 #include <queue.h>
+#include <errno.h>
 
 #include <nuttx/kmalloc.h>
 
+#include "fs.h"
 #include "semaphore/semaphore.h"
 
 /****************************************************************************
@@ -95,47 +97,76 @@
 
 int sem_unlink(FAR const char *name)
 {
-  FAR nsem_t *psem;
+  FAR struct inode *inode;
-  int         ret = ERROR;
+  FAR const char  *relpath = NULL;
+  char fullpath[MAX_SEMPATH];
+  int errcode;
+  int ret;
 
-  /* Verify the input values */
+  /* Get the full path to the semaphore */
 
-  if (name)
+  snprintf(fullpath, MAX_SEMPATH, CONFIG_FS_NAMED_SEMPATH "/%s", name);
+
+  /* Get the inode for this semaphore. */
+
+  sched_lock();
+  inode = inode_find(fullpath, &relpath);
+  if (!inode)
     {
-      sched_lock();
+      /* There is no inode that includes in this path */
 
-      /* Find the named semaphore */
+      errcode = ENOENT;
-
+      goto errout;
-      psem = sem_findnamed(name);
-
-      /* Check if the semaphore was found */
-
-      if (psem)
-        {
-          /* If the named semaphore was found and if there are no
-           * connects to it, then deallocate it
-           */
-
-          if (!psem->nconnect)
-            {
-              dq_rem((FAR dq_entry_t*)psem, &g_nsems);
-              sched_kfree(psem);
-            }
-
-          /* If one or more process still has the semaphore open,
-           * then just mark it as unlinked.  The unlinked semaphore will
-           * be deleted when the final process closes the semaphore.
-           */
-
-          else
-            {
-              psem->unlinked = true;
-            }
-          ret = OK;
-        }
-
-      sched_unlock();
     }
 
-  return ret;
+  /* Verify that what we found is, indeed, a semaphore */
+
+  if (!INODE_IS_NAMEDSEM(inode))
+    {
+      errcode = ENXIO;
+      goto errout_with_inode;
+    }
+
+  /* Refuse to unlink the inode if it has children.  I.e., if it is
+   * functioning as a directory and the directory is not empty.
+   */
+
+  inode_semtake();
+  if (inode->i_child != NULL)
+    {
+      errcode = ENOTEMPTY;
+      goto errout_with_semaphore;
+    }
+
+  /* Mark the inode as deleted */
+
+  inode->i_flags |= FSNODEFLAG_DELETED;
+
+  /* Remove the old inode from the tree.  Because we hold a reference count
+   * on the inode, it will not be deleted now.
+   */
+
+  ret = inode_remove(fullpath);
+  if (ret < 0)
+    {
+      errcode = -ret;
+      goto errout_with_semaphore;
+    }
+
+  /* Now we do not release the reference count in the normal way (by calling
+   * inode release.  Rather, we call sem_close().  sem_close will decrement
+   * the reference count on the inode.  But it will also free the semaphore
+   * if that reference count decrements to zero.  Since we hold one reference,
+   * that can only occur if the semaphore is not in-use.
+   */
+
+  return sem_close((FAR sem_t *)&inode->u.i_nsem);
+
+errout_with_semaphore:
+  inode_semgive();
+errout_with_inode:
+  inode_release(inode);
+errout:
+  set_errno(errcode);
+  return ERROR;
 }

fs/smartfs/Make.defs

@@ -49,6 +49,5 @@ CSRCS += smartfs_mksmartfs.c
 
 DEPPATH += --dep-path smartfs
 VPATH += :smartfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)smartfs}
 
 endif

fs/vfs/Make.defs

@@ -59,7 +59,6 @@ endif
 
 DEPPATH += --dep-path vfs
 VPATH += :vfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)vfs}
 endif
 
 else
@@ -87,5 +86,4 @@ endif
 
 DEPPATH += --dep-path vfs
 VPATH += :vfs
-CFLAGS += ${shell $(INCDIR) $(INCDIROPT) "$(CC)" $(TOPDIR)$(DELIM)fs$(DELIM)vfs}
 endif

include/nuttx/semaphore.h

@@ -57,12 +57,14 @@
 #ifdef CONFIG_FS_NAMED_SEMAPHORES
 /* This is the named semaphore inode */
 
+struct inode;
 struct nsem_inode_s
 {
-  /* Payload unique to named semaphores */
+  /* Inode payload unique to named semaphores */
+
+  sem_t ns_sem;                     /* The semaphore */
+  FAR struct inode *ns_inode;       /* Containing inode */
 
-  uint16_t ns_refs;                 /* Number of open references semaphore */
-  sem_t ns_sem;                     /* The semaphore itself */
 };
 #endif
 

sched/semaphore/Make.defs

@@ -33,9 +33,8 @@
 #
 ############################################################################
 
-SEM_SRCS  = sem_initialize.c sem_destroy.c sem_open.c sem_close.c
+SEM_SRCS  = sem_initialize.c sem_destroy.c sem_wait.c sem_trywait.c
-SEM_SRCS += sem_unlink.c sem_wait.c sem_trywait.c sem_timedwait.c
+SEM_SRCS += sem_timedwait.c sem_post.c
-SEM_SRCS += sem_post.c sem_findnamed.c
 
 ifneq ($(CONFIG_DISABLE_SIGNALS),y)
 SEM_SRCS += sem_waitirq.c

sched/semaphore/sem_findnamed.c

@@ -1,100 +0,0 @@
-/************************************************************************
- * sched/semaphore/sem_findnamed.c
- *
- *   Copyright (C) 2007, 2009 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <gnutt@nuttx.org>
- *
- * 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 NuttX 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 <string.h>
-
-#include "semaphore/semaphore.h"
-
-/************************************************************************
- * Definitions
- ************************************************************************/
-
-/************************************************************************
- * Private Type Declarations
- ************************************************************************/
-
-/************************************************************************
- * Global Variables
- ************************************************************************/
-
-/************************************************************************
- * Private Variables
- ************************************************************************/
-
-/************************************************************************
- * Private Functions
- ************************************************************************/
-
-/************************************************************************
- * Public Functions
- ************************************************************************/
-
-/************************************************************************
- * Name: sem_findnamed
- *
- * Description:
- *   Search the g_nsems list to find the semaphore with the matching name.
- *
- * Parameters:
- *   name - semaphore name
- *
- * Return Value:
- *   Pointer to the semaphore or NULL if not found
- *
- ************************************************************************/
-
-FAR nsem_t *sem_findnamed(const char *name)
-{
-  FAR nsem_t *psem;
-
-  /* Search the list of named semaphores */
-
-  for (psem = (FAR nsem_t*)g_nsems.head; (psem); psem = psem->flink)
-    {
-      if (!strcmp(name, psem->name))
-        {
-          break;
-        }
-    }
-
-  return(psem);
-}
-

sched/semaphore/sem_initialize.c

@@ -39,8 +39,6 @@
 
 #include <nuttx/config.h>
 
-#include <queue.h>
-
 #include "semaphore/semaphore.h"
 
 /****************************************************************************
@@ -55,10 +53,6 @@
  * Global Variables
  ****************************************************************************/
 
-/* This is a list of dyanamically allocated named semaphores */
-
-dq_queue_t g_nsems;
-
 /****************************************************************************
  * Private Variables
  ****************************************************************************/
@@ -90,10 +84,6 @@ dq_queue_t g_nsems;
 
 void sem_initialize(void)
 {
-  /* Initialize the queue of named semaphores */
-
-  dq_init(&g_nsems);
-
   /* Initialize holder structures needed to support priority inheritiance */
 
   sem_initholders();

sched/semaphore/sem_open.c

@@ -1,208 +0,0 @@
-/****************************************************************************
- * sched/semaphore/sem_open.c
- *
- *   Copyright (C) 2007, 2008, 2012 Gregory Nutt. All rights reserved.
- *   Author: Gregory Nutt <gnutt@nuttx.org>
- *
- * 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 NuttX 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 <stdbool.h>
-#include <stdarg.h>
-#include <limits.h>
-#include <fcntl.h>
-#include <string.h>
-#include <semaphore.h>
-#include <errno.h>
-
-#include <nuttx/kmalloc.h>
-
-#include "semaphore/semaphore.h"
-
-/****************************************************************************
- * Pre-processor Definitions
- ****************************************************************************/
-
-/****************************************************************************
- * Private Type Declarations
- ****************************************************************************/
-
-/****************************************************************************
- * Global Variables
- ****************************************************************************/
-
-/****************************************************************************
- * Private Variables
- ****************************************************************************/
-
-/****************************************************************************
- * Private Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Public Functions
- ****************************************************************************/
-
-/****************************************************************************
- * Name: sem_open
- *
- * Description:
- *   This function establishes a connection between named semaphores and a
- *   task.  Following a call to sem_open() with the semaphore name, the task
- *   may reference the semaphore associated with name using the address
- *   returned by this call.  The semaphore may be used in subsequent calls
- *   to sem_wait(), sem_trywait(), and sem_post().  The semaphore remains
- *   usable until the semaphore is closed by a successful call to sem_close().
- *
- *   If a task makes multiple calls to sem_open() with the same name, then
- *   the same semaphore address is returned (provided there have been no
- *   calls to sem_unlink()).
- *
- * Parameters:
- *   name  - Semaphore name
- *   oflag - Semaphore creation options.  This may either or both of the
- *     following bit settings.
- *     oflag = 0:  Connect to the semaphore only if it already exists.
- *     oflag = O_CREAT:  Connect to the semaphore if it exists, otherwise
- *        create the semaphore.
- *     oflag = O_CREAT|O_EXCL:  Create a new semaphore
- *        unless one of this name already exists.
- *   Optional parameters.  When the O_CREAT flag is specified, two optional
- *     parameters are expected:
- *     1. mode_t mode (ignored), and
- *     2. unsigned int value.  This initial value of the semaphore. Valid
- *        initial values of the semaphore must be less than or equal to
- *        SEM_VALUE_MAX.
- *
- * Return Value:
- *   A pointer to sem_t or -1 (ERROR) if unsuccessful.
- *
- * Assumptions:
- *
- ****************************************************************************/
-
-FAR sem_t *sem_open (FAR const char *name, int oflag, ...)
-{
-  int          namelen;
-  FAR nsem_t  *psem;
-  FAR sem_t   *sem = (FAR sem_t*)ERROR;
-  va_list      arg;          /* Points to each un-named argument */
-  unsigned int value;        /* Semaphore value parameter */
-
-  /* Make sure that a non-NULL name is supplied */
-
-  if (name)
-    {
-      /* The POSIX specification requires that the "check for the
-       * existence of a semaphore and the creation of the semaphore
-       * if it does not exist shall be atomic with respect to other
-       * processes executing sem_open()..."  A simple sched_lock()
-       * should be sufficient to meet this requirement.
-       */
-
-      sched_lock();
-      namelen = strlen(name);
-      if (namelen > 0)
-        {
-          /* See if the semaphore already exists */
-
-          psem = sem_findnamed(name);
-          if (psem)
-            {
-              /* It does.  Check if the caller wanted to created
-               * a new semahore with this name.
-               */
-
-              if (!(oflag & O_CREAT) || !(oflag & O_EXCL))
-                {
-                  /* Allow a new connection to the semaphore */
-
-                  psem->nconnect++;
-                  sem = &psem->sem;
-                }
-            }
-
-          /* It doesn't exist.  Should we create one? */
-
-          else if ((oflag & O_CREAT) != 0)
-            {
-              /* Set up to get the optional arguments needed to create
-               * a message queue.
-               */
-
-              va_start(arg, oflag);
-              (void)va_arg(arg, mode_t); /* Creation mode parameter (ignored) */
-              value = va_arg(arg, unsigned int);
-
-              /* Verify that a legal initial value was selected. */
-
-              if (value <= SEM_VALUE_MAX)
-                {
-                  /* Allocate memory for the new semaphore */
-
-                  psem = (FAR nsem_t*)kmm_malloc((sizeof(nsem_t) + namelen + 1));
-                  if (psem)
-                    {
-                      /* Initialize the named semaphore */
-
-                      sem = &psem->sem;
-                      sem_init(sem, 0, value);
-
-                      psem->nconnect = 1;
-                      psem->unlinked = false;
-                      psem->name = (FAR char*)psem + sizeof(nsem_t);
-                      strcpy(psem->name, name);
-
-                      /* Add the new semaphore to the list of named
-                       * semaphores
-                       */
-
-                      dq_addfirst((FAR dq_entry_t*)psem, &g_nsems);
-                    }
-
-                  /* Clean-up variable argument stuff */
-
-                  va_end(arg);
-                }
-            }
-        }
-
-      sched_unlock();
-    }
-
-  return sem;
-}
-

sched/semaphore/semaphore.h

@@ -57,28 +57,10 @@
  * Public Type Declarations
  ****************************************************************************/
 
-/* This is the named semaphore structure */
-
-struct nsem_s
-{
-  FAR struct nsem_s *flink;     /* Forward link */
-  FAR struct nsem_s *blink;     /* Backward link */
-  uint16_t           nconnect;  /* Number of connections to semaphore */
-  FAR char          *name;      /* Semaphore name (NULL if un-named) */
-  bool               unlinked;  /* true if the semaphore has been unlinked */
-  sem_t              sem;       /* The semaphore itself */
-};
-
-typedef struct nsem_s nsem_t;
-
 /****************************************************************************
  * Public Variables
  ****************************************************************************/
 
-/* This is a list of dynamically allocated named semaphores */
-
-extern dq_queue_t g_nsems;
-
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
@@ -95,7 +77,6 @@ extern "C"
 
 void weak_function sem_initialize(void);
 void sem_waitirq(FAR struct tcb_s *wtcb, int errcode);
-FAR nsem_t *sem_findnamed(const char *name);
 
 /* Special logic needed only by priority inheritance to manage collections of
  * holders of semaphores.
@@ -129,4 +110,3 @@ void sem_canceled(FAR struct tcb_s *stcb, FAR sem_t *sem);
 #endif
 
 #endif /* __SCHED_SEMAPHORE_SEMAPHORE_H */
-