falk-werner_webfuse/doc/protocol.md

Webufse 2 Protocol

Endianness

All numeric data types are transferred in Big Endian.
For instance, the uint32 value 1 will be transferred as

00 00 00 01

Data Types

Basic data types

Data Type	Width	Description
bool	8 bit	boolean value
u8	8 bit	8 bit unsigned integer
u32	32 bit	32 bit unsigned integer
u64	64 bit	64 bit unsigned integer
i32	32 bit	32 bit signed integer

Derrived integral types

Data Type	Base Type	Description
uid	u32	user ID
gid	u32	group ID
dev	u64	device ID
handle	u64	file handle

Flags and Enums

Data Type	Base Type	Description
result	i32	result type of methods
access_mode	u32	mode of access method
mode	u32	file type and permissions
open_flags	i32	flags of open method
rename_flags	u8	flags of rename method

result

Value Range	Description
0	method call succeed
negative value	error code (see below)
positive value	amount of bytes read or written (read and write only)

Error Code	Value	Description
E2BIG	-7	argument list too long
EACCES	-13	permission denied
EAGAIN	-11	resource temporarily unavailable
EBADF	-9	bad file descriptor
EBUSY	-16	device or resource busy
EDESTADDRREQ	-89	destination address required
EDQUOT	-122	disk quota exceeded
EEXIST	-17	file exists
EFAULT	-14	bad address
EFBIG	-27	file too large
EINTR	-4	interrupt function call
EINVAL	-22	invalid argument
EIO	-5	input / output error
EISDIR	-21	is a directory
ELOOP	-40	too many levels of symbolic links
EMFILE	-24	too many open files
EMLINK	-31	too many links
ENAMETOOLONG	-36	filename too long
ENFILE	-23	too many open files in system
ENODATA	-61	the named attribute does not exist, or the process has not access to this attribute
ENODEV	-19	no such device
ENOENT	-2	no such file or directory
ENOMEM	-12	not enough space / cannot allocate memory
ENOSPC	-28	no space left on device
ENOSYS	-38	function not implemented
ENOTDIR	-20	not a directory
ENOTEMPTY	-39	directory not empty
ENOTSUP	-95	operation not supported
ENXIO	-6	no such device or address
EOVERFLOW	-75	value too large to be stored in data type
EPERM	-1	operation not permitted
EPIPE	-32	broken pipe
ERANGE	-34	result too large
EROFS	-30	read-only filesystem
ETXTBSY	-26	text file busy
EXDEV	-18	improper link
EWOULDBLOCK	-11	resource temporarily unavailable

Complex Types

Data Type	Description
string	UTF-8 string
bytes	array of bytes
timestamp	date and time
attributes	file attributes
statistics	filesystem statistics

string

Field	Data Type	Description
size	u32	length of the string in bytes
data	u8[]	string data (UTF-8)

bytes

Field	Data Type	Description
size	u32	length of the byte array
data	u8[]	array data

timestamp

Field	Data Type	Description
seconds	u64	seconds sind epoch (1.1.1970)
nsec	u32	nano seconds

attributes

Field	Data Type	Description
inode	u64	Inode value
nlink	u64	Number of hard links
mode	mode (u32)	file mode flags
uid	uid (u32)	user ID
gid	gid (u32)	group ID
rdev	dev (u64)	device ID
size	u64	file size
blocks	u64	number 512-byte blocks
atime	timestamp	time of last access
mtime	timestamp	time of last modification
ctime	timestamp	time of last status change

statistics

Message

Methods

access

Field	Data Type	Description
	uint32	message id
type	uint8	message type (0x00)
path	string
mode	access_mode (i8)

Response

| Field |