Hi
You're right, perror could be used instead of strerror(-ret), it's
simpler. And I've remoded all "fflush", as you said, there are useless
and it's a tutorial about xenomai. So I think that those "fflush" aren't
necessary.
Thanks for feedback,
Philippe
Gilles Chanteperdrix wrote:
> trem wrote:
> > Hi
> >
> > Thanks for the reply (jan too). I've tried to use all of your feedback,
> > and I send you the new release of this tut02.
> >
> > (...)
> > + /* no memory-swapping for this programm */
> > + ret = mlockall(MCL_CURRENT | MCL_FUTURE);
> > + if (ret) {
> > + fprintf(stderr, "ERROR : mlockall failled: %s\n",
> strerror(-ret));
> > + fflush(stdout);
> > + exit(1);
> > + }
>
> Some further comment, mlockall returns its error in errno, so you should
> replace strerror(-ret) with strerror(errno), or to make it short, use
> perror.
> Also note that since you fflush stdout after having printed the error
> message, if there are any non printed message in stdout, they will only
> appear after the error message, which will make it hard for the user to
> catch the error message. Besides, exit already flushes the file
> descriptors, so flushing stdout before calling exit is useless. IMHO,
> you should call fflush(stdout) before printing the error message.
>
Index: tut02-skeleton-app.c
===================================================================
--- tut02-skeleton-app.c (révision 0)
+++ tut02-skeleton-app.c (révision 0)
@@ -0,0 +1,114 @@
+/***************************************************************************
+ * Copyright (C) 2007 by trem (Philippe Reynes) *
+ * [EMAIL PROTECTED] *
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation; either version 2 of the License, or *
+ * (at your option) any later version. *
+ * *
+ * This program is distributed in the hope that it will be useful, *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
+ * GNU General Public License for more details. *
+ * *
+ * You should have received a copy of the GNU General Public License *
+ * along with this program; if not, write to the *
+ * Free Software Foundation, Inc., *
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
+ ***************************************************************************/
+
+/**
+ * This is an example that shows how RTDM devices can be used
+ * with a user space program in realtime context.
+ *
+ * The device tut02-skeleton-drv01 stores data that you write into.
+ * When you read from this device, previously stored data is returned,
+ * and the internal buffer is erased. But you can only do a read once per
+ * write. If you try to read more than you have written, the read is
+ * blocked unless a write is done.
+ *
+ * This program does the following:
+ * - If you give an argument to the command line, this argument is written
+ * in the device (with rt_dev_write)
+ * - If you don't give an argument to the command line, the progam read
+ * in the device (with rt_dev_read).
+ *
+ * To test this application, you just need to:
+ *
+ * $ export LD_LIBRARY_PATH=<path of xenomai>/lib
+ * $ insmod tut02-skeleton-drv.ko
+ * $ ./tut02-skeleton-app "Hello Master"
+ * $ ./tut02-skeleton-app
+ *
+ */
+
+#include <stdlib.h>
+#include <stdio.h>
+#include <sys/mman.h> /* for MCL_CURRENT and MCL_FUTURE */
+#include <rtdm/rtdm.h>
+#include <native/task.h>
+
+#define DEVICE_NAME "tut02-skeleton-drv01"
+
+RT_TASK rt_task_desc;
+
+int main(int argc, char *argv[])
+{
+ char buf[1024];
+ ssize_t size;
+ int device;
+ int ret;
+
+ /* no memory-swapping for this programm */
+ ret = mlockall(MCL_CURRENT | MCL_FUTURE);
+ if (ret) {
+ perror("ERROR : mlockall has failled");
+ exit(1);
+ }
+
+ /*
+ change the current task to RT-task
+ the task has no name to allow this program to be run several times
+ */
+ ret = rt_task_shadow(&rt_task_desc, NULL, 1, 0);
+ if (ret)
+ {
+ fprintf(stderr, "ERROR : rt_task_shadow: %s\n", strerror(-ret));
+ exit(1);
+ }
+
+ /* open the device */
+ device = rt_dev_open(DEVICE_NAME, 0);
+ if (device < 0) {
+ printf("ERROR : can't open device %s (%s)\n",
+ DEVICE_NAME, strerror(-device));
+ exit(1);
+ }
+
+ /*
+ if an argument was given on the command line, write it to the device,
+ otherwise, read in the device.
+ */
+ if (argc == 2)
+ {
+ sprintf(buf, "%s", argv[1]);
+ size = rt_dev_write (device, (const void *)buf, strlen(buf) + 1);
+ printf("Write from device %s\t: %d bytes\n", DEVICE_NAME, size);
+ }
+ else
+ {
+ size = rt_dev_read (device, (void *)buf, 1024);
+ printf("Read in device %s\t: %s\n", DEVICE_NAME, buf);
+ }
+
+ /* close the device */
+ ret = rt_dev_close(device);
+ if (ret < 0) {
+ printf("ERROR : can't close device %s (%s)\n",
+ DEVICE_NAME, strerror(-ret));
+ exit(1);
+ }
+
+ return 0;
+}
Modification de propriétés sur tut02-skeleton-app.c
___________________________________________________________________
Nom : svn:eol-style
+ native
Index: tut02-skeleton-drv.c
===================================================================
--- tut02-skeleton-drv.c (révision 0)
+++ tut02-skeleton-drv.c (révision 0)
@@ -0,0 +1,198 @@
+/***************************************************************************
+ * Copyright (C) 2007 by trem (Philippe Reynes) *
+ * [EMAIL PROTECTED] *
+ * *
+ * This program is free software; you can redistribute it and/or modify *
+ * it under the terms of the GNU General Public License as published by *
+ * the Free Software Foundation; either version 2 of the License, or *
+ * (at your option) any later version. *
+ * *
+ * This program is distributed in the hope that it will be useful, *
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of *
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the *
+ * GNU General Public License for more details. *
+ * *
+ * You should have received a copy of the GNU General Public License *
+ * along with this program; if not, write to the *
+ * Free Software Foundation, Inc., *
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. *
+ ***************************************************************************/
+
+/**
+ * This kernel driver demonstrates how an RTDM device can be called from
+ * a RT task and how to use a semaphore.
+ *
+ * It is a simple device, only 4 operation are provided:
+ * - open: start device usage
+ * - close: ends device usage
+ * - write: store transfered data in an internal buffer (realtime context)
+ * - read: return previously stored data and erase buffer (realtime context)
+ *
+ */
+
+#include <linux/module.h>
+#include <rtdm/rtdm_driver.h>
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("trem");
+
+#define SIZE_MAX 1024
+#define DEVICE_NAME "tut02-skeleton-drv01"
+#define SOME_SUB_CLASS 4711
+
+/**
+ * The structure of the buffer
+ *
+ */
+typedef struct buffer_s {
+ int size;
+ char data[SIZE_MAX];
+} buffer_t;
+
+/**
+ * The global buffer
+ *
+ */
+buffer_t buffer;
+
+/**
+ * The global semaphore
+ *
+ */
+rtdm_sem_t sem;
+
+/**
+ * Open the device
+ *
+ * This function is called when the device shall be opened.
+ *
+ */
+static int simple_rtdm_open(struct rtdm_dev_context *context,
+ rtdm_user_info_t * user_info, int oflags)
+{
+ return 0;
+}
+
+/**
+ * Close the device
+ *
+ * This function is called when the device shall be closed.
+ *
+ */
+static int simple_rtdm_close(struct rtdm_dev_context *context,
+ rtdm_user_info_t * user_info)
+{
+ return 0;
+}
+
+/**
+ * Read from the device
+ *
+ * This function is called when the device is read in realtime context.
+ *
+ */
+static ssize_t simple_rtdm_read_rt(struct rtdm_dev_context *context,
+ rtdm_user_info_t * user_info, void *buf,
+ size_t nbyte)
+{
+ int ret, size;
+
+ /* take the semaphore */
+ rtdm_sem_down(&sem);
+
+ /* read the kernel buffer and sent it to user space */
+ size = (buffer.size > nbyte) ? nbyte : buffer.size;
+ ret = rtdm_safe_copy_to_user(user_info, buf, buffer.data, size);
+
+ /* if an error has occured, send it to user */
+ if (ret) return ret;
+
+ /* clean the kernel buffer */
+ buffer.size = 0;
+
+ return size;
+}
+
+/**
+ * Write in the device
+ *
+ * This function is called when the device is written in realtime context.
+ *
+ */
+static ssize_t simple_rtdm_write_rt(struct rtdm_dev_context *context,
+ rtdm_user_info_t * user_info,
+ const void *buf, size_t nbyte)
+{
+ int ret;
+
+ /* write the user buffer in the kernel buffer */
+ buffer.size = (nbyte > SIZE_MAX) ? SIZE_MAX : nbyte;
+ ret = rtdm_safe_copy_from_user(user_info, buffer.data, buf, buffer.size);
+
+ /* if an error has occured, send it to user */
+ if (ret) return ret;
+
+ /* release the semaphore */
+ rtdm_sem_up(&sem);
+
+ return nbyte;
+}
+
+/**
+ * This structure describe the simple RTDM device
+ *
+ */
+static struct rtdm_device device = {
+ .struct_version = RTDM_DEVICE_STRUCT_VER,
+
+ .device_flags = RTDM_NAMED_DEVICE,
+ .context_size = 0,
+ .device_name = DEVICE_NAME,
+
+ .open_nrt = simple_rtdm_open,
+ .open_rt = simple_rtdm_open,
+
+ .ops = {
+ .close_nrt = simple_rtdm_close,
+ .close_rt = simple_rtdm_close,
+ .read_rt = simple_rtdm_read_rt,
+ .write_rt = simple_rtdm_write_rt,
+ },
+
+ .device_class = RTDM_CLASS_EXPERIMENTAL,
+ .device_sub_class = SOME_SUB_CLASS,
+ .profile_version = 1,
+ .driver_name = "SimpleRTDM",
+ .driver_version = RTDM_DRIVER_VER(0, 1, 2),
+ .peripheral_name = "Simple RTDM example",
+ .provider_name = "trem",
+ .proc_name = device.device_name,
+};
+
+/**
+ * This function is called when the module is loaded
+ *
+ * It simply registers the RTDM device.
+ *
+ */
+int __init simple_rtdm_init(void)
+{
+ buffer.size = 0; /* clear the buffer */
+ rtdm_sem_init(&sem, 0); /* init the global semaphore */
+
+ return rtdm_dev_register(&device);
+}
+
+/**
+ * This function is called when the module is unloaded
+ *
+ * It unregister the RTDM device, polling at 1000 ms for pending users.
+ *
+ */
+void __exit simple_rtdm_exit(void)
+{
+ rtdm_dev_unregister(&device, 1000);
+}
+
+module_init(simple_rtdm_init);
+module_exit(simple_rtdm_exit);
Modification de propriétés sur tut02-skeleton-drv.c
___________________________________________________________________
Nom : svn:eol-style
+ native
Index: Makefile
===================================================================
--- Makefile (révision 2484)
+++ Makefile (copie de travail)
@@ -1,13 +1,13 @@
###### CONFIGURATION ######
### List of applications to be build
-APPLICATIONS = tut01-skeleton-app
+APPLICATIONS = tut01-skeleton-app tut02-skeleton-app
### Note: to override the search path for the xeno-config script, use "make XENO=..."
### List of modules to be build
-MODULES = heartbeat-x86 tut01-skeleton-drv
+MODULES = heartbeat-x86 tut01-skeleton-drv tut02-skeleton-drv
### Note: to override the kernel source path, use "make KSRC=..."
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