graphics/nxterm: Remove the nxterm_unregister interface. The correct way to unregister a device is to unlink it.

TODO

@@ -2486,8 +2486,8 @@ o Graphics Subsystem (graphics/)
                Within the OS, NxTK currently used only in graphics/nxterm.  With
                some effort, I think NxTerm could be moved to apps/ as well.
 
-               Currently, nxterm violates POSIX interface.  nxtk_register() and
+               Currently, nxterm violates POSIX interface.  nxterm_redraw() and
-               nx_register() called from application.  see apps/examples/nxterm
+               nxterm_kbdin() are called from applications.  see apps/examples/nxterm
                and apps/graphics/NxWidgets/nxwm./src/cnxterm.cxx.
 
   Status:      Open

configs/sam4e-ek/nxwm/defconfig

@@ -57,7 +57,6 @@ CONFIG_NET_BROADCAST=y
 CONFIG_NET_ICMP=y
 CONFIG_NET_ICMP_SOCKET=y
 CONFIG_NET_MAX_LISTENPORTS=16
-CONFIG_NET_SOCKOPTS=y
 CONFIG_NET_TCP=y
 CONFIG_NET_TCPBACKLOG=y
 CONFIG_NET_TCP_CONNS=16

configs/samv71-xult/vnxwm/defconfig

@@ -65,7 +65,6 @@ CONFIG_NETUTILS_WEBCLIENT=y
 CONFIG_NET_ARP_SEND=y
 CONFIG_NET_ICMP=y
 CONFIG_NET_ICMP_SOCKET=y
-CONFIG_NET_SOCKOPTS=y
 CONFIG_NET_STATISTICS=y
 CONFIG_NET_TCP=y
 CONFIG_NET_TCPBACKLOG=y

configs/shenzhou/nxwm/defconfig

@@ -48,7 +48,6 @@ CONFIG_NETUTILS_WEBCLIENT=y
 CONFIG_NET_ICMP=y
 CONFIG_NET_ICMP_SOCKET=y
 CONFIG_NET_MAX_LISTENPORTS=16
-CONFIG_NET_SOCKOPTS=y
 CONFIG_NET_STATISTICS=y
 CONFIG_NET_TCP=y
 CONFIG_NET_TCPBACKLOG=y

configs/stm3240g-eval/nxterm/defconfig

@@ -52,7 +52,6 @@ CONFIG_NET_BROADCAST=y
 CONFIG_NET_ICMP=y
 CONFIG_NET_ICMP_SOCKET=y
 CONFIG_NET_MAX_LISTENPORTS=40
-CONFIG_NET_SOCKOPTS=y
 CONFIG_NET_STATISTICS=y
 CONFIG_NET_TCP=y
 CONFIG_NET_TCPBACKLOG=y

configs/stm32f429i-disco/nxwm/defconfig

@@ -6,7 +6,6 @@
 # modifications.
 #
 # CONFIG_ARCH_FPU is not set
-# CONFIG_FB_CMAP is not set
 # CONFIG_NXFONTS_DISABLE_16BPP is not set
 # CONFIG_NXTK_DEFAULT_BORDERCOLORS is not set
 # CONFIG_NX_DISABLE_16BPP is not set

graphics/nxterm/Make.defs

@@ -37,8 +37,11 @@ ifeq ($(CONFIG_NXTERM),y)
 
 CSRCS += nx_register.c nxterm_driver.c nxterm_font.c nxterm_putc.c
 CSRCS += nxterm_redraw.c nxterm_register.c nxterm_scroll.c
-CSRCS += nxterm_vt100.c nxterm_unregister.c nxtk_register.c
+CSRCS += nxterm_vt100.c nxtk_register.c nxtool_register.c
-CSRCS += nxtool_register.c
+
+ifneq ($(CONFIG_DISABLE_PSEUDOFS_OPERATIONS),y)
+CSRCS += nxterm_unregister.c
+endif
 
 ifeq ($(CONFIG_NXTERM_NXKBDIN),y)
 CSRCS += nxterm_kbdin.c

graphics/nxterm/nxterm.h

@@ -122,43 +122,47 @@ struct nxterm_bitmap_s
 struct nxterm_state_s
 {
   FAR const struct nxterm_operations_s *ops; /* Window operations */
-  FAR void *handle;                         /* The window handle */
+  FAR void *handle;                          /* The window handle */
-  FAR struct nxterm_window_s wndo;          /* Describes the window and font */
+  FAR struct nxterm_window_s wndo;           /* Describes the window and font */
-  sem_t exclsem;                            /* Forces mutually exclusive access */
+  sem_t exclsem;                             /* Forces mutually exclusive access */
 #ifdef CONFIG_DEBUG_FEATURES
-  pid_t holder;                             /* Deadlock avoidance */
+  pid_t holder;                              /* Deadlock avoidance */
 #endif
-  uint8_t minor;                            /* Device minor number */
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  bool unlinked;                             /* True:  Driver has been unlinked */
+  uint8_t orefs;                             /* Open reference count */
+#endif
+  uint8_t minor;                             /* Device minor number */
 
   /* Text output support */
 
-  uint8_t fheight;                          /* Max height of a font in pixels */
+  uint8_t fheight;                           /* Max height of a font in pixels */
-  uint8_t fwidth;                           /* Max width of a font in pixels */
+  uint8_t fwidth;                            /* Max width of a font in pixels */
-  uint8_t spwidth;                          /* The width of a space */
+  uint8_t spwidth;                           /* The width of a space */
 
-  uint16_t maxchars;                        /* Size of the bm[] array */
+  uint16_t maxchars;                         /* Size of the bm[] array */
-  uint16_t nchars;                          /* Number of chars in the bm[] array */
+  uint16_t nchars;                           /* Number of chars in the bm[] array */
 
-  struct nxgl_point_s fpos;                 /* Next display position */
+  struct nxgl_point_s fpos;                  /* Next display position */
 
   /* VT100 escape sequence processing */
 
-  char seq[VT100_MAX_SEQUENCE];             /* Buffered characters */
+  char seq[VT100_MAX_SEQUENCE];              /* Buffered characters */
-  uint8_t nseq;                             /* Number of buffered characters */
+  uint8_t nseq;                              /* Number of buffered characters */
 
   /* Font cache data storage */
 
-  FCACHE fcache;                            /* Font cache handle */
+  FCACHE fcache;                             /* Font cache handle */
   struct nxterm_bitmap_s cursor;
   struct nxterm_bitmap_s bm[CONFIG_NXTERM_MXCHARS];
 
   /* Keyboard input support */
 
 #ifdef CONFIG_NXTERM_NXKBDIN
-  sem_t waitsem;                            /* Supports waiting for input data */
+  sem_t waitsem;                             /* Supports waiting for input data */
-  uint8_t nwaiters;                         /* Number of threads waiting for data */
+  uint8_t nwaiters;                          /* Number of threads waiting for data */
-  uint8_t head;                             /* rxbuffer head/input index */
+  uint8_t head;                              /* rxbuffer head/input index */
-  uint8_t tail;                             /* rxbuffer tail/output index */
+  uint8_t tail;                              /* rxbuffer tail/output index */
 
   uint8_t rxbuffer[CONFIG_NXTERM_KBDBUFSIZE];
 
@@ -184,6 +188,7 @@ extern const struct file_operations g_nxterm_drvrops;
 /****************************************************************************
  * Public Function Prototypes
  ****************************************************************************/
+
 /* Semaphore helpers */
 
 #ifdef CONFIG_DEBUG_FEATURES
@@ -194,11 +199,14 @@ int nxterm_sempost(FAR struct nxterm_state_s *priv);
 #  define nxterm_sempost(p) nxsem_post(&p->exclsem)
 #endif
 
-/* Common device registration */
+/* Common device registration/un-registration */
 
 FAR struct nxterm_state_s *nxterm_register(NXTERM handle,
     FAR struct nxterm_window_s *wndo, FAR const struct nxterm_operations_s *ops,
     int minor);
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+void nxterm_unregister(FAR struct nxterm_state_s *priv);
+#endif
 
 #ifdef CONFIG_NXTERM_NXKBDIN
 ssize_t nxterm_read(FAR struct file *filep, FAR char *buffer, size_t len);

graphics/nxterm/nxterm_driver.c

@@ -56,8 +56,12 @@
  ****************************************************************************/
 
 static int     nxterm_open(FAR struct file *filep);
+static int     nxterm_close(FAR struct file *filep);
 static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
                  size_t buflen);
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+static int     nxterm_unlink(FAR struct inode *inode);
+#endif
 
 /****************************************************************************
  * Public Data
@@ -70,15 +74,19 @@ static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
 const struct file_operations g_nxterm_drvrops =
 {
   nxterm_open,  /* open */
-  0,           /* close */
+  nxterm_close, /* close */
   nxterm_read,  /* read */
   nxterm_write, /* write */
-  0,           /* seek */
+  0,            /* seek */
-  0            /* ioctl */
+  0             /* ioctl */
 #ifndef CONFIG_DISABLE_POLL
   ,
   nxterm_poll   /* poll */
 #endif
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  ,
+  nxterm_unlink /* unlink */
+#endif
 };
 
 #else /* CONFIG_NXTERM_NXKBDIN */
@@ -86,14 +94,18 @@ const struct file_operations g_nxterm_drvrops =
 const struct file_operations g_nxterm_drvrops =
 {
   nxterm_open,  /* open */
-  0,           /* close */
+  nxterm_close, /* close */
-  0,           /* read */
+  0,            /* read */
   nxterm_write, /* write */
-  0,           /* seek */
+  0,            /* seek */
-  0            /* ioctl */
+  0             /* ioctl */
 #ifndef CONFIG_DISABLE_POLL
   ,
-  0            /* poll */
+  0             /* poll */
+#endif
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  ,
+  nxterm_unlink /* unlink */
 #endif
 };
 
@@ -130,12 +142,66 @@ static int nxterm_open(FAR struct file *filep)
     }
 #endif
 
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  /* Increment the count of open file references */
+
+  DEBUGASSERT(priv->orefs != UINT8_MAX);
+  priv->orefs++;
+#endif
+
   /* Assign the driver structure to the file */
 
   filep->f_priv = priv;
   return OK;
 }
 
+/****************************************************************************
+ * Name: nxterm_close
+ ****************************************************************************/
+
+static int nxterm_close(FAR struct file *filep)
+{
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+  FAR struct nxterm_state_s *priv;
+  int ret;
+
+  /* Recover our private state structure */
+
+  DEBUGASSERT(filep != NULL && filep->f_priv != NULL);
+  priv = (FAR struct nxterm_state_s *)filep->f_priv;
+
+  /* Get exclusive access */
+
+  ret = nxterm_semwait(priv);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Has the driver been unlinked?  Was this the last open refernce to the
+   * terminal driver?
+   */
+
+  DEBUGASSERT(priv->orefs > 0);
+  if (priv->unlinked && priv->orefs <= 1)
+    {
+      /* Yes.. Unregister the terminal device */
+
+      nxterm_unregister(priv);
+    }
+  else
+    {
+      /* No.. Just decrement the count of open file references */
+
+      priv->orefs--;
+    }
+
+  nxterm_sempost(priv);
+#endif
+
+  return OK;
+}
+
 /****************************************************************************
  * Name: nxterm_write
  ****************************************************************************/
@@ -151,7 +217,7 @@ static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
 
   /* Recover our private state structure */
 
-  DEBUGASSERT(filep && filep->f_priv);
+  DEBUGASSERT(filep != NULL && filep->f_priv != NULL);
   priv = (FAR struct nxterm_state_s *)filep->f_priv;
 
   /* Get exclusive access */
@@ -248,6 +314,49 @@ static ssize_t nxterm_write(FAR struct file *filep, FAR const char *buffer,
   return (ssize_t)buflen;
 }
 
+/****************************************************************************
+ * Name: nxterm_unlink
+ ****************************************************************************/
+
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+static int nxterm_unlink(FAR struct inode *inode)
+{
+  FAR struct nxterm_state_s *priv;
+  int ret;
+
+  DEBUGASSERT(inode != NULLL && inode->i_private != NULL);
+  priv = inode->i_private;
+
+  /* Get exclusive access */
+
+  ret = nxterm_semwait(priv);
+  if (ret < 0)
+    {
+      return ret;
+    }
+
+  /* Are there open references to the terminal driver? */
+
+  if (priv->orefs > 0)
+    {
+      /* Yes.. Just mark the driver unlinked.  Resources will be cleaned up
+       * when the final reference is close.
+       */
+
+      priv->unlinked = true;
+    }
+  else
+    {
+      /* No.. Unregister the terminal device now */
+
+      nxterm_unregister(priv);
+    }
+
+  nxterm_sempost(priv);
+  return OK;
+}
+#endif
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/

graphics/nxterm/nxterm_unregister.c

@@ -50,6 +50,8 @@
 
 #include "nxterm.h"
 
+#ifndef CONFIG_DISABLE_PSEUDOFS_OPERATIONS
+
 /****************************************************************************
  * Public Functions
  ****************************************************************************/
@@ -58,27 +60,24 @@
  * Name: nxterm_unregister
  *
  * Description:
- *   Un-register to NX console device.
+ *   Un-register an NX console device.
  *
  * Input Parameters:
- *   handle - A handle previously returned by nx_register, nxtk_register, or
+ *   priv - NxTerm private state structure instance.
- *     nxtool_register.
  *
  * Returned Value:
  *   None
  *
  ****************************************************************************/
 
-void nxterm_unregister(NXTERM handle)
+void nxterm_unregister(FAR struct nxterm_state_s *priv)
 {
-  FAR struct nxterm_state_s *priv;
   char devname[NX_DEVNAME_SIZE];
 
-  DEBUGASSERT(handle);
+  DEBUGASSERT(priv != NULL);
 
-  /* Get the reference to the driver structure from the handle */
+  /* Destroy semaphores */
 
-  priv = (FAR struct nxterm_state_s *)handle;
   nxsem_destroy(&priv->exclsem);
 #ifdef CONFIG_NXTERM_NXKBDIN
   nxsem_destroy(&priv->waitsem);
@@ -95,5 +94,7 @@ void nxterm_unregister(NXTERM handle)
 
   /* Free the private data structure */
 
-  kmm_free(handle);
+  kmm_free(priv);
 }
+
+#endif /* !CONFIG_DISABLE_PSEUDOFS_OPERATIONS */

include/nuttx/nx/nxterm.h

@@ -298,26 +298,6 @@ NXTERM nxtk_register(NXTKWINDOW hfwnd, FAR struct nxterm_window_s *wndo,
 NXTERM nxtool_register(NXTKWINDOW hfwnd, FAR struct nxterm_window_s *wndo,
                        int minor);
 
-/****************************************************************************
- * Name: nxterm_unregister
- *
- * Description:
- *   Un-register to NX console device.
- *
- *   This is an internal NuttX interface and should not be called directly
- *   from applications.
- *
- * Input Parameters:
- *   handle - A handle previously returned by nx_register, nxtk_register, or
- *     nxtool_register.
- *
- * Returned Value:
- *   None
- *
- ****************************************************************************/
-
-void nxterm_unregister(NXTERM handle);
-
 /****************************************************************************
  * Name: nxterm_redraw
  *