* Implement ioctl support. On high level interface only

"restricted" ioctls are supported (which are defined with the
_IO(), _IOR(), _IOW() or _IOWR() macros).  Unrestricted ioctls
will only be allwed to CUSE (Character Device in Userspace)
servers.  Patch by Tejun Heo

5 files changed, 303 insertions, 1 deletions

diff --git a/example/.cvsignore b/example/.cvsignore
index 56dabc1..7332bc0 100644
--- a/example/.cvsignore
+++ b/example/.cvsignore
@@ -6,4 +6,6 @@ fusexmp_fh
 null
 hello
 hello_ll
+fioc
+fioclient
 .libs
diff --git a/example/Makefile.am b/example/Makefile.am
index 91f33cc..43b195d 100644
--- a/example/Makefile.am
+++ b/example/Makefile.am
@@ -1,7 +1,13 @@
 ## Process this file with automake to produce Makefile.in
 
 AM_CPPFLAGS = -I$(top_srcdir)/include -D_FILE_OFFSET_BITS=64 -D_REENTRANT
-noinst_PROGRAMS = fusexmp fusexmp_fh null hello hello_ll
+noinst_HEADERS = fioc.h
+noinst_PROGRAMS = fusexmp fusexmp_fh null hello hello_ll fioc fioclient
 
 LDADD = ../lib/libfuse.la @libfuse_libs@
 fusexmp_fh_LDADD = ../lib/libfuse.la ../lib/libulockmgr.la @libfuse_libs@
+
+fioclient_CPPFLAGS =
+fioclient_LDFLAGS =
+fioclient_LDADD =
+
diff --git a/example/fioc.c b/example/fioc.c
new file mode 100644
index 0000000..d0dce15
--- /dev/null
+++ b/example/fioc.c
@@ -0,0 +1,211 @@
+/*
+  FUSE fioc: FUSE ioctl example
+  Copyright (C) 2008       SUSE Linux Products GmbH
+  Copyright (C) 2008       Tejun Heo <teheo@suse.de>
+
+  This program can be distributed under the terms of the GNU GPL.
+  See the file COPYING.
+
+  gcc -Wall `pkg-config fuse --cflags --libs` fioc.c -o fioc
+*/
+
+#define FUSE_USE_VERSION 26
+
+#include <fuse.h>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <time.h>
+#include <errno.h>
+
+#include "fioc.h"
+
+#define FIOC_NAME	"fioc"
+
+enum {
+	FIOC_NONE,
+	FIOC_ROOT,
+	FIOC_FILE,
+};
+
+static void *fioc_buf;
+static size_t fioc_size;
+
+static int fioc_resize(size_t new_size)
+{
+	void *new_buf;
+
+	if (new_size == fioc_size)
+		return 0;
+
+	new_buf = realloc(fioc_buf, new_size);
+	if (!new_buf && new_size)
+		return -ENOMEM;
+
+	if (new_size > fioc_size)
+		memset(new_buf + fioc_size, 0, new_size - fioc_size);
+
+	fioc_buf = new_buf;
+	fioc_size = new_size;
+
+	return 0;
+}
+
+static int fioc_expand(size_t new_size)
+{
+	if (new_size > fioc_size)
+		return fioc_resize(new_size);
+	return 0;
+}
+
+static int fioc_file_type(const char *path)
+{
+	if (strcmp(path, "/") == 0)
+		return FIOC_ROOT;
+	if (strcmp(path, "/" FIOC_NAME) == 0)
+		return FIOC_FILE;
+	return FIOC_NONE;
+}
+
+static int fioc_getattr(const char *path, struct stat *stbuf)
+{
+	stbuf->st_uid = getuid();
+	stbuf->st_gid = getgid();
+	stbuf->st_atime = stbuf->st_mtime = time(NULL);
+
+	switch (fioc_file_type(path)) {
+	case FIOC_ROOT:
+		stbuf->st_mode = S_IFDIR | 0755;
+		stbuf->st_nlink = 2;
+		break;
+	case FIOC_FILE:
+		stbuf->st_mode = S_IFREG | 0644;
+		stbuf->st_nlink = 1;
+		stbuf->st_size = fioc_size;
+		break;
+	case FIOC_NONE:
+		return -ENOENT;
+	}
+
+	return 0;
+}
+
+static int fioc_open(const char *path, struct fuse_file_info *fi)
+{
+	(void) fi;
+
+	if (fioc_file_type(path) != FIOC_NONE)
+		return 0;
+	return -ENOENT;
+}
+
+static int fioc_do_read(char *buf, size_t size, off_t offset)
+{
+	if (offset >= fioc_size)
+		return 0;
+
+	if (size > fioc_size - offset)
+		size = fioc_size - offset;
+
+	memcpy(buf, fioc_buf + offset, size);
+
+	return size;
+}
+
+static int fioc_read(const char *path, char *buf, size_t size,
+		     off_t offset, struct fuse_file_info *fi)
+{
+	(void) fi;
+
+	if (fioc_file_type(path) != FIOC_FILE)
+		return -EINVAL;
+
+	return fioc_do_read(buf, size, offset);
+}
+
+static int fioc_do_write(const char *buf, size_t size, off_t offset)
+{
+	if (fioc_expand(offset + size))
+		return -ENOMEM;
+
+	memcpy(fioc_buf + offset, buf, size);
+
+	return size;
+}
+
+static int fioc_write(const char *path, const char *buf, size_t size,
+		      off_t offset, struct fuse_file_info *fi)
+{
+	(void) fi;
+
+	if (fioc_file_type(path) != FIOC_FILE)
+		return -EINVAL;
+
+	return fioc_do_write(buf, size, offset);
+}
+
+static int fioc_truncate(const char *path, off_t size)
+{
+	if (fioc_file_type(path) != FIOC_FILE)
+		return -EINVAL;
+
+	return fioc_resize(size);
+}
+
+static int fioc_readdir(const char *path, void *buf, fuse_fill_dir_t filler,
+			off_t offset, struct fuse_file_info *fi)
+{
+	(void) fi;
+	(void) offset;
+
+	if (fioc_file_type(path) != FIOC_ROOT)
+		return -ENOENT;
+
+	filler(buf, ".", NULL, 0);
+	filler(buf, "..", NULL, 0);
+	filler(buf, FIOC_NAME, NULL, 0);
+
+	return 0;
+}
+
+static int fioc_ioctl(const char *path, int cmd, void *arg,
+		      struct fuse_file_info *fi, unsigned int flags, void *data)
+{
+	(void) arg;
+	(void) fi;
+	(void) flags;
+
+	if (fioc_file_type(path) != FIOC_FILE)
+		return -EINVAL;
+
+	if (flags & FUSE_IOCTL_COMPAT)
+		return -ENOSYS;
+
+	switch (cmd) {
+	case FIOC_GET_SIZE:
+		*(size_t *)data = fioc_size;
+		return 0;
+
+	case FIOC_SET_SIZE:
+		fioc_resize(*(size_t *)data);
+		return 0;
+	}
+
+	return -EINVAL;
+}
+
+static struct fuse_operations fioc_oper = {
+	.getattr	= fioc_getattr,
+	.readdir	= fioc_readdir,
+	.truncate	= fioc_truncate,
+	.open		= fioc_open,
+	.read		= fioc_read,
+	.write		= fioc_write,
+	.ioctl		= fioc_ioctl,
+};
+
+int main(int argc, char *argv[])
+{
+	return fuse_main(argc, argv, &fioc_oper, NULL);
+}
diff --git a/example/fioc.h b/example/fioc.h
new file mode 100644
index 0000000..c1d9cdf
--- /dev/null
+++ b/example/fioc.h
@@ -0,0 +1,17 @@
+/*
+  FUSE-ioctl: ioctl support for FUSE
+  Copyright (C) 2008       SUSE Linux Products GmbH
+  Copyright (C) 2008       Tejun Heo <teheo@suse.de>
+
+  This program can be distributed under the terms of the GNU GPL.
+  See the file COPYING.
+*/
+
+#include <sys/types.h>
+#include <sys/uio.h>
+#include <sys/ioctl.h>
+
+enum {
+	FIOC_GET_SIZE = _IOR('E', 0, size_t),
+	FIOC_SET_SIZE = _IOW('E', 1, size_t),
+};
diff --git a/example/fioclient.c b/example/fioclient.c
new file mode 100644
index 0000000..3ab63b2
--- /dev/null
+++ b/example/fioclient.c
@@ -0,0 +1,66 @@
+/*
+  FUSE fioclient: FUSE ioctl example client
+  Copyright (C) 2008       SUSE Linux Products GmbH
+  Copyright (C) 2008       Tejun Heo <teheo@suse.de>
+
+  This program can be distributed under the terms of the GNU GPL.
+  See the file COPYING.
+
+  gcc -Wall fioclient.c -o fioclient
+*/
+
+#include <sys/types.h>
+#include <sys/fcntl.h>
+#include <sys/stat.h>
+#include <sys/ioctl.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <ctype.h>
+#include <errno.h>
+#include "fioc.h"
+
+const char *usage =
+"Usage: fioclient FIOC_FILE [SIZE]\n"
+"\n"
+"       get size if SIZE is omitted, set size otherwise\n"
+"\n";
+
+int main(int argc, char **argv)
+{
+	size_t size;
+	int fd;
+
+	if (argc < 2) {
+		goto usage;
+	}
+
+	fd = open(argv[1], O_RDWR);
+	if (fd < 0) {
+		perror("open");
+		return 1;
+	}
+
+	if (argc == 2) {
+		if (ioctl(fd, FIOC_GET_SIZE, &size)) {
+			perror("ioctl");
+			return 1;
+		}
+		printf("%zu\n", size);
+	} else {
+		char *endp;
+
+		size = strtoul(argv[2], &endp, 0);
+		if (endp == argv[2] || *endp != '\0')
+			goto usage;
+
+		if (ioctl(fd, FIOC_SET_SIZE, &size)) {
+			perror("ioctl");
+			return 1;
+		}
+	}
+	return 0;
+
+usage:
+	fprintf(stderr, usage);
+	return 1;
+}