From bdc19f90ef7c404cd7d36d7353296d4d570dbe05 Mon Sep 17 00:00:00 2001
From: Matheus <matheusuky@gmail.com>
Date: Sun, 7 Aug 2022 13:13:42 -0300
Subject: [PATCH] vfs and tmpfs read

---
 src/fs/tmpfs.c           | 15 ++++++++++++++-
 src/fs/vfs.c             | 34 +++++++++++++++++++++++++++++-----
 src/include/kernel/vfs.h |  3 +++
 3 files changed, 46 insertions(+), 6 deletions(-)

diff --git a/src/fs/tmpfs.c b/src/fs/tmpfs.c
index e816793b..fbc2e7f0 100644
--- a/src/fs/tmpfs.c
+++ b/src/fs/tmpfs.c
@@ -53,6 +53,19 @@ static int tmpfs_write(int* error, vnode_t* node, void* buff, size_t count, size
 	return count;
 }
 
+static int tmpfs_read(int *error, vnode_t* node, void* buff, size_t count, size_t offset){
+	
+	size_t sizemax = node->st.st_size - offset;
+	
+	if(count > sizemax)
+		count = sizemax;
+	
+	memcpy(buff, node->fsdata, count);
+
+	return count;
+	
+}
+
 static int tmpfs_unmount(fs_t* fs) UNIMPLEMENTED
 static int tmpfs_open(dirnode_t* parent, char* name) UNIMPLEMENTED
 static int tmpfs_close(vnode_t* node) UNIMPLEMENTED
@@ -110,7 +123,7 @@ static int tmpfs_create(dirnode_t* parent, char* name, mode_t mode){
 }
 
 static fscalls_t funcs = {
-	tmpfs_mount, tmpfs_unmount, tmpfs_open, tmpfs_close, tmpfs_mkdir, tmpfs_create, tmpfs_write
+	tmpfs_mount, tmpfs_unmount, tmpfs_open, tmpfs_close, tmpfs_mkdir, tmpfs_create, tmpfs_write, tmpfs_read
 };
 
 
diff --git a/src/fs/vfs.c b/src/fs/vfs.c
index fcd61886..337fb4bd 100644
--- a/src/fs/vfs.c
+++ b/src/fs/vfs.c
@@ -60,11 +60,15 @@ int vfs_write(int* error, vnode_t* node, void* buff, size_t count, size_t offset
 
 	int type = GETTYPE(node->st.st_mode);
 	
-	if(type == TYPE_DIR || type == TYPE_LINK)
-		return EINVAL;
-	
-	if(type == TYPE_BLOCKDEV || type == TYPE_CHARDEV)
-		return ENOSYS; // TODO change this when the device manager is implemented :)
+	if(type == TYPE_DIR || type == TYPE_LINK){
+		*error = EINVAL;
+		return -1;
+	}
+
+	if(type == TYPE_BLOCKDEV || type == TYPE_CHARDEV){
+		*error = ENOSYS;
+		return -1; // TODO change this when the device manager is implemented :)
+	}
 
 	int writecount = node->fs->calls->write(error, node, buff, count, offset);
 
@@ -72,6 +76,26 @@ int vfs_write(int* error, vnode_t* node, void* buff, size_t count, size_t offset
 	
 }
 
+int vfs_read(int* error, vnode_t* node, void* buff, size_t count, size_t offset){
+	
+	int type = GETTYPE(node->st.st_mode);
+	
+	if(type == TYPE_DIR || type == TYPE_LINK){
+		*error = EINVAL;
+		return -1;
+	}
+
+	if(type == TYPE_BLOCKDEV || type == TYPE_CHARDEV){
+		*error = ENOSYS;
+		return -1; // TODO change this when the device manager is implemented :)
+	}
+
+	int readcount = node->fs->calls->read(error, node, buff, count, offset);
+
+	return readcount;
+
+}
+
 int vfs_close(vnode_t* node){
 	
 	vfs_releasenode(node);
diff --git a/src/include/kernel/vfs.h b/src/include/kernel/vfs.h
index 8ee86b4f..191231a8 100644
--- a/src/include/kernel/vfs.h
+++ b/src/include/kernel/vfs.h
@@ -54,6 +54,8 @@ typedef struct _fscalls_t {
 	int	 (*create)(dirnode_t* parent, char* name, mode_t mode);
 	//	 write to a file
 	int	 (*write)(int* error, vnode_t* node, void* buff, size_t count, size_t offset);
+	//	 read from a file
+	int	 (*read)(int* error, vnode_t* node, void* buff, size_t count, size_t offset);
 } fscalls_t;
 
 
@@ -64,6 +66,7 @@ int vfs_close(vnode_t* node);
 int vfs_mkdir(dirnode_t* ref, char* path, mode_t mode);
 int vfs_create(dirnode_t* ref, char* path, mode_t mode);
 int vfs_write(int* error, vnode_t* node, void* buff, size_t count, size_t offset);
+int vfs_read(int* error, vnode_t* node, void* buff, size_t count, size_t offset);
 
 void vfs_init();
 dirnode_t* vfs_root();