1 files changed, 103 insertions, 12 deletions

diff --git a/src/kernel/vfs.c b/src/kernel/vfs.c
index 538fbee..1720a6b 100644
--- a/src/kernel/vfs.c
+++ b/src/kernel/vfs.c
@@ -1,30 +1,121 @@
 #include "vfs.h"
-#include "task.h"
 
-typedef unsigned int size_t;
+#include <kernel/task.h>
 
-//static vfs_node vfs_root;
+#define VFS_MAX_VOLS  8
+#define VFS_MAX_FILES 10
 
-int vfs_open(const char *path, int flags, int mode);
-size_t vfs_read(int fd, void *buf, size_t count);
-size_t vfs_write(int fd, const void *buf, size_t count);
-int vfs_close(int fd);
+static vfs_volume vfs_volumes[VFS_MAX_VOLS];
+static vfs_file vfs_files[VFS_MAX_FILES];
 
 void vfs_svc(uint32_t *args)
 {
 	switch (args[0]) {
 	case 0:
-		*((int *)args[4]) = vfs_open(args[1], args[2], args[3]);
+		*((int *)args[3]) = vfs_mount((vfs_volume_funcs *)args[1],
+			args[2]);
 		break;
 	case 1:
-		*((int *)args[4]) = vfs_read(args[1], args[2], args[3]);
+		*((int *)args[3]) = vfs_open((const char *)args[1], args[2]);
 		break;
 	case 2:
-		*((int *)args[4]) = vfs_write(args[1], args[2], args[3]);
+		*((int *)args[4]) = vfs_read(args[1], args[2], (uint8_t *)args[3]);
 		break;
-	case 3:
-		*((int *)args[2]) = vfs_close(args[1]);
+	default:
 		break;
 	}
 }
 
+void vfs_init(void)
+{
+	for (int i = 0; i < VFS_MAX_VOLS; i++)
+		vfs_volumes[i].flags = 0;
+	for (int i = 0; i < VFS_MAX_FILES; i++)
+		vfs_files[i].flags = 0;
+}
+
+int vfs_mount(vfs_volume_funcs *funcs, uint32_t flags)
+{
+	for (int i = 0; i < VFS_MAX_VOLS; i++) {
+		if (!(vfs_volumes[i].flags && VFS_MOUNTED)) {
+			vfs_volumes[i].flags = VFS_MOUNTED | flags;
+			vfs_volumes[i].funcs = funcs;
+			return i;
+		}
+	}
+
+	return -1;
+}
+
+int vfs_get_drive(const char *path)
+{
+	// Validate parameters
+	if (path[0] == '\0' || path[1] == '\0' || path[1] != ':' ||
+		path[2] == '\0' || path[2] != '/')
+		return -1;
+
+	// Find chosen drive
+	int drive = -1;
+	for (int i = 0; i < VFS_MAX_VOLS; i++) {
+		if (path[0] == ('a' + i) || path[0] == ('A' + i)) {
+			drive = i;
+			break;
+		}
+	}
+
+	if (drive == -1 || !(vfs_volumes[drive].flags && VFS_MOUNTED))
+		return -1;
+
+	return drive;
+}
+
+int vfs_open(const char *path, uint32_t flags)
+{
+	int drive = vfs_get_drive(path);
+	if (drive == -1)
+		return -1;
+	if (vfs_volumes[drive].funcs->open == 0)
+		return -1;
+
+	// Find available file handle
+	int file = -1;
+	for (int i = 0; i < VFS_MAX_FILES; i++) {
+		if (!(vfs_files[i].flags & VFS_FILE_OPEN)) {
+			file = i;
+			break;
+		}
+	}
+
+	if (file == -1)
+		return -1;
+
+	vfs_files[file].flags = VFS_FILE_OPEN | flags;
+	vfs_files[file].vol = drive;
+	vfs_files[file].pid = task_getpid();
+	vfs_files[file].fsinfo =
+		vfs_volumes[drive].funcs->open(path + 3);
+
+	return file;
+}
+
+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_volumes[vfs_files[fd].vol].funcs->read == 0)
+		return -1;
+	if (vfs_files[fd].pid != task_getpid())
+		return 0;
+	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);
+
+	if (ret < count)
+		vfs_files[fd].flags |= VFS_EOF;
+
+	return ret;
+}
+