Beginning of a VFS implemented. C++ is great.

4 files changed, 250 insertions, 0 deletions

diff --git a/src/kernel/vfs/node.cpp b/src/kernel/vfs/node.cpp
new file mode 100644
index 0000000..9900a3c
--- /dev/null
+++ b/src/kernel/vfs/node.cpp
@@ -0,0 +1,122 @@
+#include "node.h"
+#include "vdir.h"
+#include <core/monitor.h>
+
+int node::open(process *proc, int mode) {
+	//TODO : permission checks
+	return 0;	// ok
+}
+
+int node::stat(file_info *info) {
+	info->type = type;
+	info->dev_type = dev_type;
+	info->mode = mode;
+	info->uid = uid;
+	info->gid = gid;
+	info->size = this->get_size();
+	return 0;
+}
+
+node *root = 0;
+
+void vfs_setup() {
+	root = new vdir(0);
+	root->add_child(".dev", new vdir(root));
+
+	monitor_write("[VFS] ");
+}
+
+node* vfs_find(node* root, char* path) {
+	node* el = root;
+	char *member = path;
+	
+	while (*path != 0 && el != 0) {
+		if (*path == '/') {
+			if (member == path) {
+				member++;
+				path++;
+			} else {
+				*path = 0;
+				el = el->get_child(member);
+				path++;
+				member = path;
+			}
+		} else {
+			path++;
+		}
+	}
+	if (el != 0 && member != path) {
+		el = el->get_child(member);
+	}
+
+	return el;
+}
+
+node* vfs_read_fd(FILE d) {
+	return current_process->fd.at(d);
+}
+
+// Syscalls
+
+static FILE i_open(node* r, char* filename, int mode) {
+	node* f = vfs_find(r, filename);
+	if (f == 0) return E_NOT_FOUND;
+	//TODO : different actions depending on open mode
+	int e = f->open(current_process, mode);
+	if (e != 0) return e;
+	return current_process->fd.add(f);
+}
+
+FILE open(char* filename, int mode) {
+	return i_open(root, filename, mode);
+}
+
+FILE open_relative(FILE root, char* filename, int mode) {
+	node* n = vfs_read_fd(root);
+	if (n == 0) return E_INVALID_FD;
+	return i_open(n, filename, mode);
+}
+
+int stat(char* filename, file_info *info) {
+	node *f = vfs_find(root, filename);
+	if (f == 0) return E_NOT_FOUND;
+	return f->stat(info);
+}
+
+int stat_relative(FILE root, char* filename, file_info *info) {
+	node *r = vfs_read_fd(root);
+	if (r == 0) return E_INVALID_FD;
+	node *f = vfs_find(r, filename);
+	if (f == 0) return E_NOT_FOUND;
+	return f->stat(info);
+}
+
+int statf(FILE file, file_info *info) {
+	node *f = vfs_read_fd(file);
+	if (f == 0) return E_INVALID_FD;
+	return f->stat(info);
+}
+
+void close(FILE file) {
+	node *f = vfs_read_fd(file);
+	if (f != 0) {
+		f->close(current_process);
+		current_process->fd.set(file, 0);
+	}
+}
+
+int read(FILE file, size_t offset, size_t len, char* buffer) {
+	node *f = vfs_read_fd(file);
+	if (f == 0) return E_INVALID_FD;
+	return f->read(offset, len, buffer);
+}
+
+int write(FILE file, size_t offset, size_t len, char* buffer) {
+	node *f = vfs_read_fd(file);
+	if (f == 0) return E_INVALID_FD;
+	return f->write(offset, len, buffer);
+}
+
+int link(char* from, char* to, int mode) {
+	return E_NOT_IMPLEMENTED;
+}
diff --git a/src/kernel/vfs/node.h b/src/kernel/vfs/node.h
new file mode 100644
index 0000000..2d16dab
--- /dev/null
+++ b/src/kernel/vfs/node.h
@@ -0,0 +1,41 @@
+#ifndef DEF_VFS_NODE_H
+#define DEF_VFS_NODE_H
+
+#include <tce/vfs.h>
+#include <tce/syscalls.h>
+
+#include <task/task.h>
+
+class node {
+	public:
+	node* parent;
+	int type, dev_type;
+	int mode, uid, gid;
+
+	node(node* p, int t) : parent(p), type(t) {}
+	
+	virtual int open(process *proc, int mode);
+	virtual void close(process *proc) {}
+	virtual int read(size_t offset, size_t len, char *buffer) { return E_NOT_IMPLEMENTED; }
+	virtual int write(size_t offset, size_t len, char* buffer) { return E_NOT_IMPLEMENTED; }
+	int stat(file_info *info);
+	virtual node* get_child(char* name) { return 0; }
+	virtual int add_child(char* name, node *child) { return E_NOT_IMPLEMENTED; }
+	virtual size_t get_size() { return 0; }
+};
+
+void vfs_setup();
+node* vfs_find(node* root, char* filename);
+
+// syscall interface
+FILE open(char* filename, int mode);
+FILE open_relative(FILE root, char* filename, int mode);
+int stat(char* filename, file_info *info);
+int stat_relative(FILE root, char* filename, file_info *info);
+int statf(FILE file, file_info *info);
+void close(FILE file);
+int read(FILE file, size_t offset, size_t len, char *buffer);
+int write(FILE file, size_t offset, size_t len, char *buffer);
+int link(char* from, char* to, int mode);
+
+#endif
diff --git a/src/kernel/vfs/vdir.cpp b/src/kernel/vfs/vdir.cpp
new file mode 100644
index 0000000..299c0e7
--- /dev/null
+++ b/src/kernel/vfs/vdir.cpp
@@ -0,0 +1,55 @@
+#include "vdir.h"
+
+vdir::vdir(node* parent) : node(parent, FT_DIR), children(8, 64) {
+	children.add(new vdir_child(".", this));
+	child_count = 1;
+
+	if (parent != 0) {
+		children.add(new vdir_child("..", parent));
+		child_count++;
+	}
+}
+
+node* vdir::get_child(char* name) {
+	for (unsigned i = 0; i < child_count; i++) {
+		vdir_child *c = children.at(i);
+		ASSERT(c != 0);
+		if (strcmp(c->name, name) == 0) return c->el;
+	}
+	return 0;
+}
+
+int vdir::read(size_t offset, size_t len, char* buffer) {
+	if (offset >= child_count) return 0;
+	vdir_child *c = children.at(offset);
+	ASSERT(c != 0);
+	size_t nlen = strlen(c->name);
+	if (len <= nlen) {
+		return E_TOO_SHORT;
+	}
+	strcpy(buffer, c->name);
+	return nlen;
+}
+
+int vdir::write(size_t offset, size_t len, char* buffer) {
+	// rename file
+	if (offset >= child_count) return E_INVALID_RANGE;
+	vdir_child *c = children.at(offset);
+	ASSERT(c != 0);
+	if (len == 0) return E_INVALID;
+	kfree(c->name);
+	c->name = (char*)kmalloc(len + 1);
+	for (unsigned i = 0; i < len; i++) c->name[i] = buffer[i];
+	c->name[len] = 0;
+	return len;
+}
+
+size_t vdir::get_size() {
+	return child_count;
+}
+
+int vdir::add_child(char* name, node *child) {
+	ASSERT((int)child_count == children.add(new vdir_child(name, child)));
+	child_count++;
+	return 0;
+}
diff --git a/src/kernel/vfs/vdir.h b/src/kernel/vfs/vdir.h
new file mode 100644
index 0000000..9595409
--- /dev/null
+++ b/src/kernel/vfs/vdir.h
@@ -0,0 +1,32 @@
+#ifndef DEF_VFS_VDIR_H
+#define DEF_VFS_VDIR_H
+
+#include "node.h"
+#include <lib/earray.h>
+#include <string.h>
+
+struct vdir_child {
+	char* name;
+	node *el;
+
+	vdir_child(char* na, node* nd) : el(nd) {
+		name = strdup(na);
+	}
+};
+
+class vdir : public node {
+	earray<vdir_child> children;
+	size_t child_count;
+	
+	public:
+	vdir(node* parent);
+
+	virtual int read(size_t offset, size_t len, char* buffer);
+	virtual int write(size_t offset, size_t len, char* buffer);		// rename file
+	virtual node* get_child(char* name);
+	virtual int add_child(char* name, node *child);
+	virtual size_t get_size();
+};
+
+#endif
+