Null device

kernel/fs/nulldev.c

@@ -0,0 +1,48 @@
+/* vim: tabstop=4 shiftwidth=4 noexpandtab
+ * Null Device
+ */
+
+#include <system.h>
+#include <fs.h>
+
+uint32_t read_null(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
+uint32_t write_null(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
+void open_null(fs_node_t *node, uint8_t read, uint8_t write);
+void close_null(fs_node_t *node);
+
+uint32_t read_null(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
+	memset(buffer, 0x00, size);
+	return size;
+}
+
+uint32_t write_null(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer) {
+	return size;
+}
+
+void open_null(fs_node_t * node, uint8_t read, uint8_t write) {
+	return;
+}
+
+void close_null(fs_node_t * node) {
+	return;
+}
+
+fs_node_t * null_device_create() {
+	fs_node_t * fnode = malloc(sizeof(fnode));
+	fnode->inode = 0;
+	fnode->name[0] = 'n';
+	fnode->name[1] = 'u';
+	fnode->name[2] = 'l';
+	fnode->name[3] = 'l';
+	fnode->name[4] = '\0';
+	fnode->uid = 0;
+	fnode->gid = 0;
+	fnode->flags = 0;
+	fnode->read    = read_null;
+	fnode->write   = write_null;
+	fnode->open    = open_null;
+	fnode->close   = close_null;
+	fnode->readdir = NULL;
+	fnode->finddir = NULL;
+	return fnode;
+}

kernel/include/fs.h

@@ -45,6 +45,7 @@ struct dirent {
 };
 
 extern fs_node_t *fs_root;
+extern fs_node_t * null_device_create();
 
 uint32_t read_fs(fs_node_t * node, uint32_t offset, uint32_t size, uint8_t * buffer);
 uint32_t write_fs(fs_node_t * node, uint32_t offset, uint32_t size, uint8_t * buffer);

userspace/terminal.c

@@ -2696,7 +2696,10 @@ int main(int argc, char ** argv) {
 					_use_freetype = 1;
 					break;
 				case 'h':
-					printf("terminal - ansi graphical terminal");
+					printf("terminal - ansi graphical terminal\n");
+					printf("   -f      Run with freetype enabled.\n");
+					printf("   -h      Print this help text.\n");
+					return 0;
 					break;
 				default:
 					break;