hello world from initrd

1 files changed, 62 insertions, 10 deletions

diff --git a/src/kernel/vfs.c b/src/kernel/vfs.c
index 6236691..b9be9bc 100644
--- a/src/kernel/vfs.c
+++ b/src/kernel/vfs.c
@@ -1,3 +1,23 @@
+/**
+ * @file vfs.c
+ * An implementation of filesystem abstraction
+ *
+ * Copyright (C) 2018 Clyne Sullivan
+ *
+ * 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 3 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, see <https://www.gnu.org/licenses/>.
+ */
+
 #include "vfs.h"
 
 #include <kernel/task.h>
@@ -10,6 +30,11 @@
 static vfs_volume vfs_volumes[VFS_MAX_VOLS];
 static vfs_file vfs_files[VFS_MAX_FILES];
 
+#define VFS_PID_CHECK(fpid) { \
+	uint32_t pid = task_getpid(); \
+	if (pid != fpid && fpid != 0) \
+		return 0; }
+
 void vfs_svc(uint32_t *args)
 {
 	switch (args[0]) {
@@ -114,7 +139,8 @@ int vfs_open(const char *path, uint32_t flags)
 	vfs_files[file].flags = VFS_FILE_OPEN | flags;
 	vfs_files[file].vol = drive;
 	vfs_files[file].pid = task_getpid();
-	vfs_files[file].fsinfo = fsinfo;
+	vfs_files[file].info.pos = 0;
+	vfs_files[file].info.fsinfo = fsinfo;
 
 	return file;
 }
@@ -125,14 +151,13 @@ int vfs_close(int fd)
 		return -1;
 	if (vfs_volumes[vfs_files[fd].vol].funcs->close == 0)
 		return -1;
-	if (vfs_files[fd].pid != task_getpid())
-		return -1;
+	VFS_PID_CHECK(vfs_files[fd].pid);
 	if (!(vfs_files[fd].flags & VFS_FILE_OPEN))
 		return 0;
 
 	// TODO care
 	/*int ret =*/ vfs_volumes[vfs_files[fd].vol].funcs->close(
-		vfs_files[fd].fsinfo);
+		&vfs_files[fd].info);
 
 	vfs_files[fd].flags = 0;
 	vfs_files[fd].pid = 0;
@@ -143,16 +168,17 @@ uint32_t vfs_read(int fd, uint32_t count, uint8_t *buffer)
 {
 	if (fd < 0 || fd > VFS_MAX_FILES || count == 0 || buffer == 0)
 		return 0;
+	if (!(vfs_files[fd].flags & VFS_FILE_OPEN))
+		return -1;
 	if (vfs_volumes[vfs_files[fd].vol].funcs->read == 0)
 		return -1;
-	if (vfs_files[fd].pid != task_getpid())
-		return 0;
+	VFS_PID_CHECK(vfs_files[fd].pid);
 	if ((!(vfs_files[fd].flags & VFS_FILE_READ)) || (vfs_files[fd].flags &
 		VFS_EOF))
 		return 0;
 
 	uint32_t ret = vfs_volumes[vfs_files[fd].vol].funcs->read(
-		vfs_files[fd].fsinfo, count, buffer);
+		&vfs_files[fd].info, count, buffer);
 
 	if (ret < count)
 		vfs_files[fd].flags |= VFS_EOF;
@@ -164,17 +190,18 @@ uint32_t vfs_write(int fd, uint32_t count, const uint8_t *buffer)
 {
 	if (fd < 0 || fd > VFS_MAX_FILES || count == 0 || buffer == 0)
 		return 0;
+	if (!(vfs_files[fd].flags & VFS_FILE_OPEN))
+		return -1;
 	if (vfs_volumes[vfs_files[fd].vol].funcs->write == 0)
 		return -1;
-	if (vfs_files[fd].pid != task_getpid())
-		return 0;
+	VFS_PID_CHECK(vfs_files[fd].pid);
 	// TODO append?
 	if ((!(vfs_files[fd].flags & VFS_FILE_WRITE)) || (vfs_files[fd].flags &
 		VFS_EOF))
 		return 0;
 
 	uint32_t ret = vfs_volumes[vfs_files[fd].vol].funcs->write(
-		vfs_files[fd].fsinfo, count, buffer);
+		&vfs_files[fd].info, count, buffer);
 
 	if (ret < count)
 		vfs_files[fd].flags |= VFS_EOF;
@@ -182,3 +209,28 @@ uint32_t vfs_write(int fd, uint32_t count, const uint8_t *buffer)
 	return ret;
 }
 
+int vfs_seek(int fd, int32_t offset, int whence)
+{
+	if (fd < 0 || fd > VFS_MAX_FILES)
+		return -1;
+	if (!(vfs_files[fd].flags & VFS_FILE_OPEN))
+		return -1;
+	if (vfs_volumes[vfs_files[fd].vol].funcs->seek == 0)
+		return -1;
+	VFS_PID_CHECK(vfs_files[fd].pid);
+
+	return vfs_volumes[vfs_files[fd].vol].funcs->seek(&vfs_files[fd].info,
+		offset, whence);
+}
+
+int32_t vfs_tell(int fd)
+{
+	if (fd < 0 || fd > VFS_MAX_FILES)
+		return -1;
+	if (!(vfs_files[fd].flags & VFS_FILE_OPEN))
+		return -1;
+	VFS_PID_CHECK(vfs_files[fd].pid);
+
+	return (int32_t)vfs_files[fd].info.pos;
+}
+