libmtp_rs/
util.rs

1//! Utilities that doesn't fit anywhere else, mostly contains internal crate functions
2//! (which are not public) and other useful public items.
3
4use libmtp_sys as ffi;
5
6/// Must return type on callbacks (send and get files)
7#[derive(Debug, Copy, Clone)]
8pub enum CallbackReturn {
9    /// Return this to continue the operation.
10    Continue,
11    /// Return this to cancel the operation.
12    Cancel,
13}
14
15#[allow(clippy::transmute_ptr_to_ref)]
16pub(crate) unsafe extern "C" fn progress_func_handler(
17    sent: u64,
18    total: u64,
19    data: *const libc::c_void,
20) -> libc::c_int {
21    let closure: &mut &mut dyn FnMut(u64, u64) -> CallbackReturn = std::mem::transmute(data);
22    match closure(sent, total) {
23        CallbackReturn::Continue => 0,
24        CallbackReturn::Cancel => 1,
25    }
26}
27
28/// Must return type of send and getter handlers that deal with raw bytes.
29#[derive(Debug, Copy, Clone)]
30pub enum HandlerReturn {
31    /// Return this if every went ok together with how many bytes
32    /// you read or writed.
33    Ok(u32),
34
35    /// Return this if there was an error.
36    Error,
37
38    /// Return this if you want to cancel the operation earlier.
39    Cancel,
40}
41
42impl HandlerReturn {
43    pub(crate) fn is_error(&self) -> bool {
44        matches!(&self, HandlerReturn::Error)
45    }
46
47    pub(crate) fn is_cancel(&self) -> bool {
48        matches!(&self, HandlerReturn::Cancel)
49    }
50}
51
52#[allow(clippy::transmute_ptr_to_ref)]
53pub(crate) unsafe extern "C" fn data_put_func_handler(
54    _params: *mut libc::c_void,
55    private: *mut libc::c_void,
56    sendlen: u32,
57    data: *mut libc::c_uchar,
58    putlen: *mut u32,
59) -> u16 {
60    let (handler_return, closure): &mut (
61        &mut HandlerReturn,
62        &mut dyn FnMut(&[u8]) -> HandlerReturn,
63    ) = std::mem::transmute(private);
64
65    let data = prim_array_ptr_to_vec!(data, u8, sendlen);
66
67    **handler_return = closure(&data);
68    let ret = match **handler_return {
69        HandlerReturn::Ok(len) => {
70            // Shouldn't be null
71            *putlen = len;
72
73            ffi::LIBMTP_HANDLER_RETURN_OK
74        }
75
76        HandlerReturn::Error => ffi::LIBMTP_HANDLER_RETURN_ERROR,
77        HandlerReturn::Cancel => ffi::LIBMTP_HANDLER_RETURN_CANCEL,
78    };
79
80    ret as u16
81}
82
83#[allow(clippy::transmute_ptr_to_ref)]
84pub(crate) unsafe extern "C" fn data_get_func_handler(
85    _params: *mut libc::c_void,
86    private: *mut libc::c_void,
87    wantlen: u32,
88    data: *mut libc::c_uchar,
89    gotlen: *mut u32,
90) -> u16 {
91    let (handler_return, closure): &mut (
92        &mut HandlerReturn,
93        &mut dyn FnMut(&mut [u8]) -> HandlerReturn,
94    ) = std::mem::transmute(private);
95
96    let mut rsdata = vec![0 as u8; wantlen as usize];
97
98    **handler_return = closure(&mut rsdata);
99    let ret = match **handler_return {
100        HandlerReturn::Ok(len) => {
101            // Shouldn't be null
102            *gotlen = len;
103
104            libc::memcpy(
105                data as *mut _,
106                rsdata.as_ptr() as *const _,
107                wantlen as usize,
108            );
109
110            ffi::LIBMTP_HANDLER_RETURN_OK
111        }
112
113        HandlerReturn::Error => ffi::LIBMTP_HANDLER_RETURN_ERROR,
114        HandlerReturn::Cancel => ffi::LIBMTP_HANDLER_RETURN_CANCEL,
115    };
116
117    ret as u16
118}
libmtp_rs/util.rs

libmtp_rs/
util.rs
