Implement procfs demonstration.

diff --git a/hello_procfs.c b/hello_procfs.c
index 1390972..a78eff8 100644 (file)
--- a/hello_procfs.c
+++ b/hello_procfs.c
@@ -19,17 +19,65 @@
 
 #include <linux/module.h>
 #include <linux/proc_fs.h>
+#include <linux/seq_file.h>
 
 MODULE_AUTHOR("Thadeu Lima de Souza Cascardo <cascardo@holoscopio.com>");
 MODULE_LICENSE("GPL");
 
+static int hello_show(struct seq_file *file, void *data)
+{
+       seq_puts(file, "Hello, world!\n");
+       return 0;
+}
+
+#if 0
+static void * hello_start(struct seq_file *file, loff_t *pos)
+{
+       return NULL;
+}
+
+static void hello_stop(struct seq_file *file, void *data)
+{
+}
+
+static void * hello_next(struct seq_file *file, void *data, loff_t *pos)
+{
+       return NULL;
+}
+
+static const struct seq_operations hello_seqops =
+{
+       .start = hello_start,
+       .stop = hello_stop,
+       .next = hello_next,
+       .show = hello_show,
+};
+#endif
+
+static int hello_procfs_open(struct inode *inode, struct file *file)
+{
+       return single_open(file, hello_show, NULL);
+}
+
+static const struct file_operations hello_procfs_fops =
+{
+       .open = hello_procfs_open,
+       .read = seq_read,
+       .llseek = seq_lseek,
+       .release = seq_release,
+};
+
 static int hello_procfs_init(void)
 {
+       struct proc_dir_entry *entry;
+       entry = create_proc_entry("gnu", 0666, NULL);
+       entry->proc_fops = &hello_procfs_fops;
        return 0;
 }
 
 static void hello_procfs_exit(void)
 {
+       remove_proc_entry("gnu", NULL);
 }
 
 module_init(hello_procfs_init);