devman and vfs: check if a function is not implemented before calling

src/fs/devfs.c

@@ -45,10 +45,6 @@ static int devfs_open(dirnode_t* parent, char* name){
 }
 
 static int devfs_close(){return 0;}
-static int devfs_mkdir() UNIMPLEMENTED
-static int devfs_create() UNIMPLEMENTED
-static int devfs_write() UNIMPLEMENTED
-static int devfs_read() UNIMPLEMENTED
 
 static int devfs_getdirent(dirnode_t* node, dent_t* buff, size_t count, uintmax_t offset, size_t* readcount){
 
@@ -84,7 +80,7 @@ static int devfs_chmod(vnode_t* node, mode_t mode){
 }
 
 static fscalls_t devfscalls = {
-	devfs_mount, devfs_unmount, devfs_open, devfs_close, devfs_mkdir, devfs_create, devfs_write, devfs_read, devfs_getdirent, devfs_chmod
+	devfs_mount, devfs_unmount, devfs_open, devfs_close, NULL, NULL, NULL, NULL, devfs_getdirent, devfs_chmod
 };
 
 void devfs_init(){

src/fs/vfs.c

@@ -87,7 +87,9 @@ int vfs_write(int* error, vnode_t* node, void* buff, size_t count, size_t offset
 		
 		return writecount;
 	}
-
+	
+	if(!node->fs->calls->write)
+		return ENOSYS;
 	
 	spinlock_acquire(&lock);
 	
@@ -156,7 +158,6 @@ int vfs_read(int* error, vnode_t* node, void* buff, size_t count, size_t offset,
 	if(!fd)
 		fd = &tmpfd;
 
-
 	int type = GETTYPE(node->st.st_mode);
 	
 	if(type == TYPE_SOCKET)
@@ -175,6 +176,9 @@ int vfs_read(int* error, vnode_t* node, void* buff, size_t count, size_t offset,
 		int readcount = devman_read(error, node->st.st_rdev, buff, count, offset);
 		return readcount;
 	}
+
+	if(!node->fs->calls->read)
+		return ENOSYS;
 	
 	spinlock_acquire(&lock);
 	
@@ -187,6 +191,9 @@ int vfs_read(int* error, vnode_t* node, void* buff, size_t count, size_t offset,
 }
 
 int vfs_close(vnode_t* node){
+	
+	if(!node->fs->calls->close)
+		return ENOSYS;
 		
 	spinlock_acquire(&lock);
 	
@@ -207,6 +214,9 @@ int vfs_close(vnode_t* node){
 int vfs_getdirent(dirnode_t* node, dent_t* buff, size_t count, uintmax_t offset, size_t* readcount){
 	
 	int err = 0;
+	
+	if(!node->vnode.fs->calls->getdirent)
+		return ENOSYS;
 
 	spinlock_acquire(&lock);
 	
@@ -295,6 +305,11 @@ int vfs_create(dirnode_t* ref, char* path, mode_t mode){
 		spinlock_release(&lock);
 		return result;
 	}
+	
+	if(!parent->vnode.fs->calls->create){
+		spinlock_release(&lock);
+		return ENOSYS;
+	}
 
 	result = parent->vnode.fs->calls->create(parent, name, mode);
 	

src/sys/devman.c

@@ -31,6 +31,10 @@ int devman_write(int *error, int dev, void* buff, size_t count, size_t offset){
 	if(major(dev) > highestmajor)
 		return ENODEV;
 
+
+	if(!majorcalls[major(dev)]->write)
+                return ENOTTY;
+
 	return majorcalls[major(dev)]->write(error, minor(dev), buff, count, offset);
 	
 	
@@ -40,6 +44,9 @@ int devman_read(int *error, int dev, void* buff, size_t count, size_t offset){
 	
 	if(major(dev) > highestmajor)
 		return ENODEV;
+
+	if(!majorcalls[major(dev)]->read)
+                return ENOTTY;
 	
 
 	return majorcalls[major(dev)]->read(error, minor(dev), buff, count, offset);
@@ -51,6 +58,9 @@ int devman_isatty(int dev){
 	
 	if(major(dev) > highestmajor)
 		return ENOTTY;
+
+	if(!majorcalls[major(dev)]->isatty)
+                return ENOTTY;
 	
 	return majorcalls[major(dev)]->isatty(minor(dev));
 	
@@ -61,6 +71,10 @@ int devman_isseekable(int dev, size_t* max){
         if(major(dev) > highestmajor)
                 return ENOTTY;
 
+	if(!majorcalls[major(dev)]->isseekable)
+                return 0;
+
+
         return majorcalls[major(dev)]->isseekable(minor(dev), max);
 
 }

src/sys/keyboard.c

@@ -127,7 +127,6 @@ int keyboard_getnew(){
 
 }
 
-static int write(int *error, int minor, void* buff, size_t count){*error = EINVAL; return -1;}
 static int read(int *error, int minor, void* buff, size_t count, size_t offset){
 	count /= sizeof(kbpacket_t);
 	if(count == 0){
@@ -146,16 +145,8 @@ static int read(int *error, int minor, void* buff, size_t count, size_t offset){
 
 }
 
-static int isatty(){
-	return ENOTTY;
-}
-
-static int seekable(){
-	return 0;
-}
-
 static devcalls calls = {
-	read, write, isatty, seekable
+	read
 };
 
 void keyboard_init(){

src/sys/pseudodevs/full.c

@@ -13,17 +13,13 @@ static int write(int* error, int minor, void* buff, size_t count, size_t offset)
 	return -1;
 }
 
-static int isatty(int minor){
-	return ENOTTY;
-}
-
 static int isseekable(int minor, size_t* max){
         *max = ~(size_t)0;
         return 0;
 }
 
 static devcalls calls = {
-	read, write, isatty, isseekable
+	read, write, NULL, isseekable
 };
 
 void fulldev_init(){

src/sys/pseudodevs/null.c

@@ -12,17 +12,13 @@ static int write(int* error, int minor, void* buff, size_t count, size_t offset)
 	return count;
 }
 
-static int isatty(int minor){
-	return ENOTTY;
-}
-
 static int isseekable(int minor, size_t* max){
         *max = ~(size_t)0;
         return 0;
 }
 
 static devcalls calls = {
-	read, write, isatty, isseekable
+	read, write, NULL, isseekable
 };
 
 void nulldev_init(){

src/sys/pseudodevs/zero.c

@@ -13,17 +13,13 @@ static int write(int* error, int minor, void* buff, size_t count, size_t offset)
 	return count;
 }
 
-static int isatty(int minor){
-	return ENOTTY;
-}
-
 static int isseekable(int minor, size_t* max){
 	*max = ~(size_t)0;
 	return 0;
 }
 
 static devcalls calls = {
-	read, write, isatty, isseekable
+	read, write, NULL, isseekable
 };
 
 void zerodev_init(){

src/video/framebuffer.c

@@ -121,10 +121,6 @@ int write(int* error, int minor, void* buff, size_t count, size_t offset){
 	return count;
 }
 
-int isatty(int minor){
-	return ENOTTY;
-}
-
 static int isseekable(int minor, size_t* max){
         
 	if(minor >= fbcount)
@@ -201,7 +197,7 @@ static map(int minor, void* addr, size_t len, size_t offset, size_t mmuflags){
 }
 
 static devcalls calls = {
-	read, write, isatty, isseekable, ioctl, NULL, map
+	read, write, NULL, isseekable, ioctl, NULL, map
 };