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1 | // ref_sharing.rs |
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1 | // ref_sharing.rs | |
2 | // |
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2 | // | |
3 | // Copyright 2019 Raphaël Gomès <rgomes@octobus.net> |
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3 | // Copyright 2019 Raphaël Gomès <rgomes@octobus.net> | |
4 | // |
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4 | // | |
5 | // Permission is hereby granted, free of charge, to any person obtaining a copy |
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5 | // Permission is hereby granted, free of charge, to any person obtaining a copy | |
6 | // of this software and associated documentation files (the "Software"), to |
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6 | // of this software and associated documentation files (the "Software"), to | |
7 | // deal in the Software without restriction, including without limitation the |
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7 | // deal in the Software without restriction, including without limitation the | |
8 | // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or |
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8 | // rights to use, copy, modify, merge, publish, distribute, sublicense, and/or | |
9 | // sell copies of the Software, and to permit persons to whom the Software is |
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9 | // sell copies of the Software, and to permit persons to whom the Software is | |
10 | // furnished to do so, subject to the following conditions: |
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10 | // furnished to do so, subject to the following conditions: | |
11 | // |
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11 | // | |
12 | // The above copyright notice and this permission notice shall be included in |
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12 | // The above copyright notice and this permission notice shall be included in | |
13 | // all copies or substantial portions of the Software. |
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13 | // all copies or substantial portions of the Software. | |
14 | // |
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14 | // | |
15 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR |
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15 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | |
16 | // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, |
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16 | // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | |
17 | // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE |
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17 | // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE | |
18 | // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER |
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18 | // AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | |
19 | // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING |
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19 | // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | |
20 | // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS |
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20 | // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS | |
21 | // IN THE SOFTWARE. |
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21 | // IN THE SOFTWARE. | |
22 |
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22 | |||
23 | //! Macros for use in the `hg-cpython` bridge library. |
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23 | //! Macros for use in the `hg-cpython` bridge library. | |
24 |
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24 | |||
25 | use crate::exceptions::AlreadyBorrowed; |
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25 | use crate::exceptions::AlreadyBorrowed; | |
26 | use cpython::{PyClone, PyObject, PyResult, Python}; |
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26 | use cpython::{exc, PyClone, PyErr, PyObject, PyResult, Python}; | |
27 | use std::cell::{Cell, Ref, RefCell, RefMut}; |
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27 | use std::cell::{Cell, Ref, RefCell, RefMut}; | |
28 | use std::ops::{Deref, DerefMut}; |
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28 | use std::ops::{Deref, DerefMut}; | |
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29 | use std::sync::atomic::{AtomicUsize, Ordering}; | |||
29 |
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30 | |||
30 | /// Manages the shared state between Python and Rust |
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31 | /// Manages the shared state between Python and Rust | |
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32 | /// | |||
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33 | /// `PySharedState` is owned by `PySharedRefCell`, and is shared across its | |||
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34 | /// derived references. The consistency of these references are guaranteed | |||
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35 | /// as follows: | |||
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36 | /// | |||
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37 | /// - The immutability of `py_class!` object fields. Any mutation of | |||
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38 | /// `PySharedRefCell` is allowed only through its `borrow_mut()`. | |||
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39 | /// - The `py: Python<'_>` token, which makes sure that any data access is | |||
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40 | /// synchronized by the GIL. | |||
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41 | /// - The `generation` counter, which increments on `borrow_mut()`. `PyLeaked` | |||
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42 | /// reference is valid only if the `current_generation()` equals to the | |||
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43 | /// `generation` at the time of `leak_immutable()`. | |||
31 | #[derive(Debug, Default)] |
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44 | #[derive(Debug, Default)] | |
32 | struct PySharedState { |
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45 | struct PySharedState { | |
33 | leak_count: Cell<usize>, |
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46 | leak_count: Cell<usize>, | |
34 | mutably_borrowed: Cell<bool>, |
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47 | mutably_borrowed: Cell<bool>, | |
|
48 | // The counter variable could be Cell<usize> since any operation on | |||
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49 | // PySharedState is synchronized by the GIL, but being "atomic" makes | |||
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50 | // PySharedState inherently Sync. The ordering requirement doesn't | |||
|
51 | // matter thanks to the GIL. | |||
|
52 | generation: AtomicUsize, | |||
35 | } |
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53 | } | |
36 |
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54 | |||
37 | // &PySharedState can be Send because any access to inner cells is |
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55 | // &PySharedState can be Send because any access to inner cells is | |
38 | // synchronized by the GIL. |
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56 | // synchronized by the GIL. | |
39 | unsafe impl Sync for PySharedState {} |
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57 | unsafe impl Sync for PySharedState {} | |
40 |
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58 | |||
41 | impl PySharedState { |
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59 | impl PySharedState { | |
42 | fn borrow_mut<'a, T>( |
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60 | fn borrow_mut<'a, T>( | |
43 | &'a self, |
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61 | &'a self, | |
44 | py: Python<'a>, |
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62 | py: Python<'a>, | |
45 | pyrefmut: RefMut<'a, T>, |
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63 | pyrefmut: RefMut<'a, T>, | |
46 | ) -> PyResult<PyRefMut<'a, T>> { |
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64 | ) -> PyResult<PyRefMut<'a, T>> { | |
47 | if self.mutably_borrowed.get() { |
|
65 | if self.mutably_borrowed.get() { | |
48 | return Err(AlreadyBorrowed::new( |
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66 | return Err(AlreadyBorrowed::new( | |
49 | py, |
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67 | py, | |
50 | "Cannot borrow mutably while there exists another \ |
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68 | "Cannot borrow mutably while there exists another \ | |
51 | mutable reference in a Python object", |
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69 | mutable reference in a Python object", | |
52 | )); |
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70 | )); | |
53 | } |
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71 | } | |
54 | match self.leak_count.get() { |
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72 | match self.leak_count.get() { | |
55 | 0 => { |
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73 | 0 => { | |
56 | self.mutably_borrowed.replace(true); |
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74 | self.mutably_borrowed.replace(true); | |
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75 | // Note that this wraps around to the same value if mutably | |||
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76 | // borrowed more than usize::MAX times, which wouldn't happen | |||
|
77 | // in practice. | |||
|
78 | self.generation.fetch_add(1, Ordering::Relaxed); | |||
57 | Ok(PyRefMut::new(py, pyrefmut, self)) |
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79 | Ok(PyRefMut::new(py, pyrefmut, self)) | |
58 | } |
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80 | } | |
59 | // TODO |
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81 | // TODO | |
60 | // For now, this works differently than Python references |
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82 | // For now, this works differently than Python references | |
61 | // in the case of iterators. |
|
83 | // in the case of iterators. | |
62 | // Python does not complain when the data an iterator |
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84 | // Python does not complain when the data an iterator | |
63 | // points to is modified if the iterator is never used |
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85 | // points to is modified if the iterator is never used | |
64 | // afterwards. |
|
86 | // afterwards. | |
65 | // Here, we are stricter than this by refusing to give a |
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87 | // Here, we are stricter than this by refusing to give a | |
66 | // mutable reference if it is already borrowed. |
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88 | // mutable reference if it is already borrowed. | |
67 | // While the additional safety might be argued for, it |
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89 | // While the additional safety might be argued for, it | |
68 | // breaks valid programming patterns in Python and we need |
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90 | // breaks valid programming patterns in Python and we need | |
69 | // to fix this issue down the line. |
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91 | // to fix this issue down the line. | |
70 | _ => Err(AlreadyBorrowed::new( |
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92 | _ => Err(AlreadyBorrowed::new( | |
71 | py, |
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93 | py, | |
72 | "Cannot borrow mutably while there are \ |
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94 | "Cannot borrow mutably while there are \ | |
73 | immutable references in Python objects", |
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95 | immutable references in Python objects", | |
74 | )), |
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96 | )), | |
75 | } |
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97 | } | |
76 | } |
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98 | } | |
77 |
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99 | |||
78 | /// Return a reference to the wrapped data and its state with an |
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100 | /// Return a reference to the wrapped data and its state with an | |
79 | /// artificial static lifetime. |
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101 | /// artificial static lifetime. | |
80 | /// We need to be protected by the GIL for thread-safety. |
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102 | /// We need to be protected by the GIL for thread-safety. | |
81 | /// |
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103 | /// | |
82 | /// # Safety |
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104 | /// # Safety | |
83 | /// |
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105 | /// | |
84 | /// This is highly unsafe since the lifetime of the given data can be |
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106 | /// This is highly unsafe since the lifetime of the given data can be | |
85 | /// extended. Do not call this function directly. |
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107 | /// extended. Do not call this function directly. | |
86 | unsafe fn leak_immutable<T>( |
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108 | unsafe fn leak_immutable<T>( | |
87 | &self, |
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109 | &self, | |
88 | py: Python, |
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110 | py: Python, | |
89 | data: &PySharedRefCell<T>, |
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111 | data: &PySharedRefCell<T>, | |
90 | ) -> PyResult<(&'static T, &'static PySharedState)> { |
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112 | ) -> PyResult<(&'static T, &'static PySharedState)> { | |
91 | if self.mutably_borrowed.get() { |
|
113 | if self.mutably_borrowed.get() { | |
92 | return Err(AlreadyBorrowed::new( |
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114 | return Err(AlreadyBorrowed::new( | |
93 | py, |
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115 | py, | |
94 | "Cannot borrow immutably while there is a \ |
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116 | "Cannot borrow immutably while there is a \ | |
95 | mutable reference in Python objects", |
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117 | mutable reference in Python objects", | |
96 | )); |
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118 | )); | |
97 | } |
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119 | } | |
98 | // TODO: it's weird that self is data.py_shared_state. Maybe we |
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120 | // TODO: it's weird that self is data.py_shared_state. Maybe we | |
99 | // can move stuff to PySharedRefCell? |
|
121 | // can move stuff to PySharedRefCell? | |
100 | let ptr = data.as_ptr(); |
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122 | let ptr = data.as_ptr(); | |
101 | let state_ptr: *const PySharedState = &data.py_shared_state; |
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123 | let state_ptr: *const PySharedState = &data.py_shared_state; | |
102 | self.leak_count.replace(self.leak_count.get() + 1); |
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124 | self.leak_count.replace(self.leak_count.get() + 1); | |
103 | Ok((&*ptr, &*state_ptr)) |
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125 | Ok((&*ptr, &*state_ptr)) | |
104 | } |
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126 | } | |
105 |
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127 | |||
106 | /// # Safety |
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128 | /// # Safety | |
107 | /// |
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129 | /// | |
108 | /// It's up to you to make sure the reference is about to be deleted |
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130 | /// It's up to you to make sure the reference is about to be deleted | |
109 | /// when updating the leak count. |
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131 | /// when updating the leak count. | |
110 | fn decrease_leak_count(&self, _py: Python, mutable: bool) { |
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132 | fn decrease_leak_count(&self, _py: Python, mutable: bool) { | |
111 | if mutable { |
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133 | if mutable { | |
112 | assert_eq!(self.leak_count.get(), 0); |
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134 | assert_eq!(self.leak_count.get(), 0); | |
113 | assert!(self.mutably_borrowed.get()); |
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135 | assert!(self.mutably_borrowed.get()); | |
114 | self.mutably_borrowed.replace(false); |
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136 | self.mutably_borrowed.replace(false); | |
115 | } else { |
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137 | } else { | |
116 | let count = self.leak_count.get(); |
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138 | let count = self.leak_count.get(); | |
117 | assert!(count > 0); |
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139 | assert!(count > 0); | |
118 | self.leak_count.replace(count - 1); |
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140 | self.leak_count.replace(count - 1); | |
119 | } |
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141 | } | |
120 | } |
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142 | } | |
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143 | ||||
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144 | fn current_generation(&self, _py: Python) -> usize { | |||
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145 | self.generation.load(Ordering::Relaxed) | |||
|
146 | } | |||
121 | } |
|
147 | } | |
122 |
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148 | |||
123 | /// `RefCell` wrapper to be safely used in conjunction with `PySharedState`. |
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149 | /// `RefCell` wrapper to be safely used in conjunction with `PySharedState`. | |
124 | /// |
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150 | /// | |
125 | /// This object can be stored in a `py_class!` object as a data field. Any |
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151 | /// This object can be stored in a `py_class!` object as a data field. Any | |
126 | /// operation is allowed through the `PySharedRef` interface. |
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152 | /// operation is allowed through the `PySharedRef` interface. | |
127 | #[derive(Debug)] |
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153 | #[derive(Debug)] | |
128 | pub struct PySharedRefCell<T> { |
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154 | pub struct PySharedRefCell<T> { | |
129 | inner: RefCell<T>, |
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155 | inner: RefCell<T>, | |
130 | py_shared_state: PySharedState, |
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156 | py_shared_state: PySharedState, | |
131 | } |
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157 | } | |
132 |
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158 | |||
133 | impl<T> PySharedRefCell<T> { |
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159 | impl<T> PySharedRefCell<T> { | |
134 | pub fn new(value: T) -> PySharedRefCell<T> { |
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160 | pub fn new(value: T) -> PySharedRefCell<T> { | |
135 | Self { |
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161 | Self { | |
136 | inner: RefCell::new(value), |
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162 | inner: RefCell::new(value), | |
137 | py_shared_state: PySharedState::default(), |
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163 | py_shared_state: PySharedState::default(), | |
138 | } |
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164 | } | |
139 | } |
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165 | } | |
140 |
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166 | |||
141 | fn borrow<'a>(&'a self, _py: Python<'a>) -> Ref<'a, T> { |
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167 | fn borrow<'a>(&'a self, _py: Python<'a>) -> Ref<'a, T> { | |
142 | // py_shared_state isn't involved since |
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168 | // py_shared_state isn't involved since | |
143 | // - inner.borrow() would fail if self is mutably borrowed, |
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169 | // - inner.borrow() would fail if self is mutably borrowed, | |
144 | // - and inner.borrow_mut() would fail while self is borrowed. |
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170 | // - and inner.borrow_mut() would fail while self is borrowed. | |
145 | self.inner.borrow() |
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171 | self.inner.borrow() | |
146 | } |
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172 | } | |
147 |
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173 | |||
148 | fn as_ptr(&self) -> *mut T { |
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174 | fn as_ptr(&self) -> *mut T { | |
149 | self.inner.as_ptr() |
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175 | self.inner.as_ptr() | |
150 | } |
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176 | } | |
151 |
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177 | |||
152 | // TODO: maybe this should be named as try_borrow_mut(), and use |
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178 | // TODO: maybe this should be named as try_borrow_mut(), and use | |
153 | // inner.try_borrow_mut(). The current implementation panics if |
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179 | // inner.try_borrow_mut(). The current implementation panics if | |
154 | // self.inner has been borrowed, but returns error if py_shared_state |
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180 | // self.inner has been borrowed, but returns error if py_shared_state | |
155 | // refuses to borrow. |
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181 | // refuses to borrow. | |
156 | fn borrow_mut<'a>(&'a self, py: Python<'a>) -> PyResult<PyRefMut<'a, T>> { |
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182 | fn borrow_mut<'a>(&'a self, py: Python<'a>) -> PyResult<PyRefMut<'a, T>> { | |
157 | self.py_shared_state.borrow_mut(py, self.inner.borrow_mut()) |
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183 | self.py_shared_state.borrow_mut(py, self.inner.borrow_mut()) | |
158 | } |
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184 | } | |
159 | } |
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185 | } | |
160 |
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186 | |||
161 | /// Sharable data member of type `T` borrowed from the `PyObject`. |
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187 | /// Sharable data member of type `T` borrowed from the `PyObject`. | |
162 | pub struct PySharedRef<'a, T> { |
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188 | pub struct PySharedRef<'a, T> { | |
163 | py: Python<'a>, |
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189 | py: Python<'a>, | |
164 | owner: &'a PyObject, |
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190 | owner: &'a PyObject, | |
165 | data: &'a PySharedRefCell<T>, |
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191 | data: &'a PySharedRefCell<T>, | |
166 | } |
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192 | } | |
167 |
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193 | |||
168 | impl<'a, T> PySharedRef<'a, T> { |
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194 | impl<'a, T> PySharedRef<'a, T> { | |
169 | /// # Safety |
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195 | /// # Safety | |
170 | /// |
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196 | /// | |
171 | /// The `data` must be owned by the `owner`. Otherwise, the leak count |
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197 | /// The `data` must be owned by the `owner`. Otherwise, the leak count | |
172 | /// would get wrong. |
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198 | /// would get wrong. | |
173 | pub unsafe fn new( |
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199 | pub unsafe fn new( | |
174 | py: Python<'a>, |
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200 | py: Python<'a>, | |
175 | owner: &'a PyObject, |
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201 | owner: &'a PyObject, | |
176 | data: &'a PySharedRefCell<T>, |
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202 | data: &'a PySharedRefCell<T>, | |
177 | ) -> Self { |
|
203 | ) -> Self { | |
178 | Self { py, owner, data } |
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204 | Self { py, owner, data } | |
179 | } |
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205 | } | |
180 |
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206 | |||
181 | pub fn borrow(&self) -> Ref<'a, T> { |
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207 | pub fn borrow(&self) -> Ref<'a, T> { | |
182 | self.data.borrow(self.py) |
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208 | self.data.borrow(self.py) | |
183 | } |
|
209 | } | |
184 |
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210 | |||
185 | pub fn borrow_mut(&self) -> PyResult<PyRefMut<'a, T>> { |
|
211 | pub fn borrow_mut(&self) -> PyResult<PyRefMut<'a, T>> { | |
186 | self.data.borrow_mut(self.py) |
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212 | self.data.borrow_mut(self.py) | |
187 | } |
|
213 | } | |
188 |
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214 | |||
189 | /// Returns a leaked reference. |
|
215 | /// Returns a leaked reference. | |
190 | pub fn leak_immutable(&self) -> PyResult<PyLeaked<&'static T>> { |
|
216 | pub fn leak_immutable(&self) -> PyResult<PyLeaked<&'static T>> { | |
191 | let state = &self.data.py_shared_state; |
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217 | let state = &self.data.py_shared_state; | |
192 | unsafe { |
|
218 | unsafe { | |
193 | let (static_ref, static_state_ref) = |
|
219 | let (static_ref, static_state_ref) = | |
194 | state.leak_immutable(self.py, self.data)?; |
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220 | state.leak_immutable(self.py, self.data)?; | |
195 | Ok(PyLeaked::new( |
|
221 | Ok(PyLeaked::new( | |
196 | self.py, |
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222 | self.py, | |
197 | self.owner, |
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223 | self.owner, | |
198 | static_ref, |
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224 | static_ref, | |
199 | static_state_ref, |
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225 | static_state_ref, | |
200 | )) |
|
226 | )) | |
201 | } |
|
227 | } | |
202 | } |
|
228 | } | |
203 | } |
|
229 | } | |
204 |
|
230 | |||
205 | /// Holds a mutable reference to data shared between Python and Rust. |
|
231 | /// Holds a mutable reference to data shared between Python and Rust. | |
206 | pub struct PyRefMut<'a, T> { |
|
232 | pub struct PyRefMut<'a, T> { | |
207 | py: Python<'a>, |
|
233 | py: Python<'a>, | |
208 | inner: RefMut<'a, T>, |
|
234 | inner: RefMut<'a, T>, | |
209 | py_shared_state: &'a PySharedState, |
|
235 | py_shared_state: &'a PySharedState, | |
210 | } |
|
236 | } | |
211 |
|
237 | |||
212 | impl<'a, T> PyRefMut<'a, T> { |
|
238 | impl<'a, T> PyRefMut<'a, T> { | |
213 | // Must be constructed by PySharedState after checking its leak_count. |
|
239 | // Must be constructed by PySharedState after checking its leak_count. | |
214 | // Otherwise, drop() would incorrectly update the state. |
|
240 | // Otherwise, drop() would incorrectly update the state. | |
215 | fn new( |
|
241 | fn new( | |
216 | py: Python<'a>, |
|
242 | py: Python<'a>, | |
217 | inner: RefMut<'a, T>, |
|
243 | inner: RefMut<'a, T>, | |
218 | py_shared_state: &'a PySharedState, |
|
244 | py_shared_state: &'a PySharedState, | |
219 | ) -> Self { |
|
245 | ) -> Self { | |
220 | Self { |
|
246 | Self { | |
221 | py, |
|
247 | py, | |
222 | inner, |
|
248 | inner, | |
223 | py_shared_state, |
|
249 | py_shared_state, | |
224 | } |
|
250 | } | |
225 | } |
|
251 | } | |
226 | } |
|
252 | } | |
227 |
|
253 | |||
228 | impl<'a, T> std::ops::Deref for PyRefMut<'a, T> { |
|
254 | impl<'a, T> std::ops::Deref for PyRefMut<'a, T> { | |
229 | type Target = RefMut<'a, T>; |
|
255 | type Target = RefMut<'a, T>; | |
230 |
|
256 | |||
231 | fn deref(&self) -> &Self::Target { |
|
257 | fn deref(&self) -> &Self::Target { | |
232 | &self.inner |
|
258 | &self.inner | |
233 | } |
|
259 | } | |
234 | } |
|
260 | } | |
235 | impl<'a, T> std::ops::DerefMut for PyRefMut<'a, T> { |
|
261 | impl<'a, T> std::ops::DerefMut for PyRefMut<'a, T> { | |
236 | fn deref_mut(&mut self) -> &mut Self::Target { |
|
262 | fn deref_mut(&mut self) -> &mut Self::Target { | |
237 | &mut self.inner |
|
263 | &mut self.inner | |
238 | } |
|
264 | } | |
239 | } |
|
265 | } | |
240 |
|
266 | |||
241 | impl<'a, T> Drop for PyRefMut<'a, T> { |
|
267 | impl<'a, T> Drop for PyRefMut<'a, T> { | |
242 | fn drop(&mut self) { |
|
268 | fn drop(&mut self) { | |
243 | self.py_shared_state.decrease_leak_count(self.py, true); |
|
269 | self.py_shared_state.decrease_leak_count(self.py, true); | |
244 | } |
|
270 | } | |
245 | } |
|
271 | } | |
246 |
|
272 | |||
247 | /// Allows a `py_class!` generated struct to share references to one of its |
|
273 | /// Allows a `py_class!` generated struct to share references to one of its | |
248 | /// data members with Python. |
|
274 | /// data members with Python. | |
249 | /// |
|
275 | /// | |
250 | /// # Warning |
|
276 | /// # Warning | |
251 | /// |
|
277 | /// | |
252 | /// TODO allow Python container types: for now, integration with the garbage |
|
278 | /// TODO allow Python container types: for now, integration with the garbage | |
253 | /// collector does not extend to Rust structs holding references to Python |
|
279 | /// collector does not extend to Rust structs holding references to Python | |
254 | /// objects. Should the need surface, `__traverse__` and `__clear__` will |
|
280 | /// objects. Should the need surface, `__traverse__` and `__clear__` will | |
255 | /// need to be written as per the `rust-cpython` docs on GC integration. |
|
281 | /// need to be written as per the `rust-cpython` docs on GC integration. | |
256 | /// |
|
282 | /// | |
257 | /// # Parameters |
|
283 | /// # Parameters | |
258 | /// |
|
284 | /// | |
259 | /// * `$name` is the same identifier used in for `py_class!` macro call. |
|
285 | /// * `$name` is the same identifier used in for `py_class!` macro call. | |
260 | /// * `$inner_struct` is the identifier of the underlying Rust struct |
|
286 | /// * `$inner_struct` is the identifier of the underlying Rust struct | |
261 | /// * `$data_member` is the identifier of the data member of `$inner_struct` |
|
287 | /// * `$data_member` is the identifier of the data member of `$inner_struct` | |
262 | /// that will be shared. |
|
288 | /// that will be shared. | |
263 | /// * `$shared_accessor` is the function name to be generated, which allows |
|
289 | /// * `$shared_accessor` is the function name to be generated, which allows | |
264 | /// safe access to the data member. |
|
290 | /// safe access to the data member. | |
265 | /// |
|
291 | /// | |
266 | /// # Safety |
|
292 | /// # Safety | |
267 | /// |
|
293 | /// | |
268 | /// `$data_member` must persist while the `$name` object is alive. In other |
|
294 | /// `$data_member` must persist while the `$name` object is alive. In other | |
269 | /// words, it must be an accessor to a data field of the Python object. |
|
295 | /// words, it must be an accessor to a data field of the Python object. | |
270 | /// |
|
296 | /// | |
271 | /// # Example |
|
297 | /// # Example | |
272 | /// |
|
298 | /// | |
273 | /// ``` |
|
299 | /// ``` | |
274 | /// struct MyStruct { |
|
300 | /// struct MyStruct { | |
275 | /// inner: Vec<u32>; |
|
301 | /// inner: Vec<u32>; | |
276 | /// } |
|
302 | /// } | |
277 | /// |
|
303 | /// | |
278 | /// py_class!(pub class MyType |py| { |
|
304 | /// py_class!(pub class MyType |py| { | |
279 | /// data inner: PySharedRefCell<MyStruct>; |
|
305 | /// data inner: PySharedRefCell<MyStruct>; | |
280 | /// }); |
|
306 | /// }); | |
281 | /// |
|
307 | /// | |
282 | /// py_shared_ref!(MyType, MyStruct, inner, inner_shared); |
|
308 | /// py_shared_ref!(MyType, MyStruct, inner, inner_shared); | |
283 | /// ``` |
|
309 | /// ``` | |
284 | macro_rules! py_shared_ref { |
|
310 | macro_rules! py_shared_ref { | |
285 | ( |
|
311 | ( | |
286 | $name: ident, |
|
312 | $name: ident, | |
287 | $inner_struct: ident, |
|
313 | $inner_struct: ident, | |
288 | $data_member: ident, |
|
314 | $data_member: ident, | |
289 | $shared_accessor: ident |
|
315 | $shared_accessor: ident | |
290 | ) => { |
|
316 | ) => { | |
291 | impl $name { |
|
317 | impl $name { | |
292 | /// Returns a safe reference to the shared `$data_member`. |
|
318 | /// Returns a safe reference to the shared `$data_member`. | |
293 | /// |
|
319 | /// | |
294 | /// This function guarantees that `PySharedRef` is created with |
|
320 | /// This function guarantees that `PySharedRef` is created with | |
295 | /// the valid `self` and `self.$data_member(py)` pair. |
|
321 | /// the valid `self` and `self.$data_member(py)` pair. | |
296 | fn $shared_accessor<'a>( |
|
322 | fn $shared_accessor<'a>( | |
297 | &'a self, |
|
323 | &'a self, | |
298 | py: Python<'a>, |
|
324 | py: Python<'a>, | |
299 | ) -> $crate::ref_sharing::PySharedRef<'a, $inner_struct> { |
|
325 | ) -> $crate::ref_sharing::PySharedRef<'a, $inner_struct> { | |
300 | use cpython::PythonObject; |
|
326 | use cpython::PythonObject; | |
301 | use $crate::ref_sharing::PySharedRef; |
|
327 | use $crate::ref_sharing::PySharedRef; | |
302 | let owner = self.as_object(); |
|
328 | let owner = self.as_object(); | |
303 | let data = self.$data_member(py); |
|
329 | let data = self.$data_member(py); | |
304 | unsafe { PySharedRef::new(py, owner, data) } |
|
330 | unsafe { PySharedRef::new(py, owner, data) } | |
305 | } |
|
331 | } | |
306 | } |
|
332 | } | |
307 | }; |
|
333 | }; | |
308 | } |
|
334 | } | |
309 |
|
335 | |||
310 | /// Manage immutable references to `PyObject` leaked into Python iterators. |
|
336 | /// Manage immutable references to `PyObject` leaked into Python iterators. | |
|
337 | /// | |||
|
338 | /// This reference will be invalidated once the original value is mutably | |||
|
339 | /// borrowed. | |||
311 | pub struct PyLeaked<T> { |
|
340 | pub struct PyLeaked<T> { | |
312 | inner: PyObject, |
|
341 | inner: PyObject, | |
313 | data: Option<T>, |
|
342 | data: Option<T>, | |
314 | py_shared_state: &'static PySharedState, |
|
343 | py_shared_state: &'static PySharedState, | |
|
344 | /// Generation counter of data `T` captured when PyLeaked is created. | |||
|
345 | generation: usize, | |||
315 | } |
|
346 | } | |
316 |
|
347 | |||
317 | // DO NOT implement Deref for PyLeaked<T>! Dereferencing PyLeaked |
|
348 | // DO NOT implement Deref for PyLeaked<T>! Dereferencing PyLeaked | |
318 | // without taking Python GIL wouldn't be safe. |
|
349 | // without taking Python GIL wouldn't be safe. Also, the underling reference | |
|
350 | // is invalid if generation != py_shared_state.generation. | |||
319 |
|
351 | |||
320 | impl<T> PyLeaked<T> { |
|
352 | impl<T> PyLeaked<T> { | |
321 | /// # Safety |
|
353 | /// # Safety | |
322 | /// |
|
354 | /// | |
323 | /// The `py_shared_state` must be owned by the `inner` Python object. |
|
355 | /// The `py_shared_state` must be owned by the `inner` Python object. | |
324 | fn new( |
|
356 | fn new( | |
325 | py: Python, |
|
357 | py: Python, | |
326 | inner: &PyObject, |
|
358 | inner: &PyObject, | |
327 | data: T, |
|
359 | data: T, | |
328 | py_shared_state: &'static PySharedState, |
|
360 | py_shared_state: &'static PySharedState, | |
329 | ) -> Self { |
|
361 | ) -> Self { | |
330 | Self { |
|
362 | Self { | |
331 | inner: inner.clone_ref(py), |
|
363 | inner: inner.clone_ref(py), | |
332 | data: Some(data), |
|
364 | data: Some(data), | |
333 | py_shared_state, |
|
365 | py_shared_state, | |
|
366 | generation: py_shared_state.current_generation(py), | |||
334 | } |
|
367 | } | |
335 | } |
|
368 | } | |
336 |
|
369 | |||
337 | /// Immutably borrows the wrapped value. |
|
370 | /// Immutably borrows the wrapped value. | |
|
371 | /// | |||
|
372 | /// Borrowing fails if the underlying reference has been invalidated. | |||
338 | pub fn try_borrow<'a>( |
|
373 | pub fn try_borrow<'a>( | |
339 | &'a self, |
|
374 | &'a self, | |
340 | py: Python<'a>, |
|
375 | py: Python<'a>, | |
341 | ) -> PyResult<PyLeakedRef<'a, T>> { |
|
376 | ) -> PyResult<PyLeakedRef<'a, T>> { | |
|
377 | self.validate_generation(py)?; | |||
342 | Ok(PyLeakedRef { |
|
378 | Ok(PyLeakedRef { | |
343 | _py: py, |
|
379 | _py: py, | |
344 | data: self.data.as_ref().unwrap(), |
|
380 | data: self.data.as_ref().unwrap(), | |
345 | }) |
|
381 | }) | |
346 | } |
|
382 | } | |
347 |
|
383 | |||
348 | /// Mutably borrows the wrapped value. |
|
384 | /// Mutably borrows the wrapped value. | |
349 | /// |
|
385 | /// | |
|
386 | /// Borrowing fails if the underlying reference has been invalidated. | |||
|
387 | /// | |||
350 | /// Typically `T` is an iterator. If `T` is an immutable reference, |
|
388 | /// Typically `T` is an iterator. If `T` is an immutable reference, | |
351 | /// `get_mut()` is useless since the inner value can't be mutated. |
|
389 | /// `get_mut()` is useless since the inner value can't be mutated. | |
352 | pub fn try_borrow_mut<'a>( |
|
390 | pub fn try_borrow_mut<'a>( | |
353 | &'a mut self, |
|
391 | &'a mut self, | |
354 | py: Python<'a>, |
|
392 | py: Python<'a>, | |
355 | ) -> PyResult<PyLeakedRefMut<'a, T>> { |
|
393 | ) -> PyResult<PyLeakedRefMut<'a, T>> { | |
|
394 | self.validate_generation(py)?; | |||
356 | Ok(PyLeakedRefMut { |
|
395 | Ok(PyLeakedRefMut { | |
357 | _py: py, |
|
396 | _py: py, | |
358 | data: self.data.as_mut().unwrap(), |
|
397 | data: self.data.as_mut().unwrap(), | |
359 | }) |
|
398 | }) | |
360 | } |
|
399 | } | |
361 |
|
400 | |||
362 | /// Converts the inner value by the given function. |
|
401 | /// Converts the inner value by the given function. | |
363 | /// |
|
402 | /// | |
364 | /// Typically `T` is a static reference to a container, and `U` is an |
|
403 | /// Typically `T` is a static reference to a container, and `U` is an | |
365 | /// iterator of that container. |
|
404 | /// iterator of that container. | |
366 | /// |
|
405 | /// | |
|
406 | /// # Panics | |||
|
407 | /// | |||
|
408 | /// Panics if the underlying reference has been invalidated. | |||
|
409 | /// | |||
|
410 | /// This is typically called immediately after the `PyLeaked` is obtained. | |||
|
411 | /// In which case, the reference must be valid and no panic would occur. | |||
|
412 | /// | |||
367 | /// # Safety |
|
413 | /// # Safety | |
368 | /// |
|
414 | /// | |
369 | /// The lifetime of the object passed in to the function `f` is cheated. |
|
415 | /// The lifetime of the object passed in to the function `f` is cheated. | |
370 | /// It's typically a static reference, but is valid only while the |
|
416 | /// It's typically a static reference, but is valid only while the | |
371 | /// corresponding `PyLeaked` is alive. Do not copy it out of the |
|
417 | /// corresponding `PyLeaked` is alive. Do not copy it out of the | |
372 | /// function call. |
|
418 | /// function call. | |
373 | pub unsafe fn map<U>( |
|
419 | pub unsafe fn map<U>( | |
374 | mut self, |
|
420 | mut self, | |
375 | py: Python, |
|
421 | py: Python, | |
376 | f: impl FnOnce(T) -> U, |
|
422 | f: impl FnOnce(T) -> U, | |
377 | ) -> PyLeaked<U> { |
|
423 | ) -> PyLeaked<U> { | |
|
424 | // Needs to test the generation value to make sure self.data reference | |||
|
425 | // is still intact. | |||
|
426 | self.validate_generation(py) | |||
|
427 | .expect("map() over invalidated leaked reference"); | |||
|
428 | ||||
378 | // f() could make the self.data outlive. That's why map() is unsafe. |
|
429 | // f() could make the self.data outlive. That's why map() is unsafe. | |
379 | // In order to make this function safe, maybe we'll need a way to |
|
430 | // In order to make this function safe, maybe we'll need a way to | |
380 | // temporarily restrict the lifetime of self.data and translate the |
|
431 | // temporarily restrict the lifetime of self.data and translate the | |
381 | // returned object back to Something<'static>. |
|
432 | // returned object back to Something<'static>. | |
382 | let new_data = f(self.data.take().unwrap()); |
|
433 | let new_data = f(self.data.take().unwrap()); | |
383 | PyLeaked { |
|
434 | PyLeaked { | |
384 | inner: self.inner.clone_ref(py), |
|
435 | inner: self.inner.clone_ref(py), | |
385 | data: Some(new_data), |
|
436 | data: Some(new_data), | |
386 | py_shared_state: self.py_shared_state, |
|
437 | py_shared_state: self.py_shared_state, | |
|
438 | generation: self.generation, | |||
|
439 | } | |||
|
440 | } | |||
|
441 | ||||
|
442 | fn validate_generation(&self, py: Python) -> PyResult<()> { | |||
|
443 | if self.py_shared_state.current_generation(py) == self.generation { | |||
|
444 | Ok(()) | |||
|
445 | } else { | |||
|
446 | Err(PyErr::new::<exc::RuntimeError, _>( | |||
|
447 | py, | |||
|
448 | "Cannot access to leaked reference after mutation", | |||
|
449 | )) | |||
387 | } |
|
450 | } | |
388 | } |
|
451 | } | |
389 | } |
|
452 | } | |
390 |
|
453 | |||
391 | impl<T> Drop for PyLeaked<T> { |
|
454 | impl<T> Drop for PyLeaked<T> { | |
392 | fn drop(&mut self) { |
|
455 | fn drop(&mut self) { | |
393 | // py_shared_state should be alive since we do have |
|
456 | // py_shared_state should be alive since we do have | |
394 | // a Python reference to the owner object. Taking GIL makes |
|
457 | // a Python reference to the owner object. Taking GIL makes | |
395 | // sure that the state is only accessed by this thread. |
|
458 | // sure that the state is only accessed by this thread. | |
396 | let gil = Python::acquire_gil(); |
|
459 | let gil = Python::acquire_gil(); | |
397 | let py = gil.python(); |
|
460 | let py = gil.python(); | |
398 | if self.data.is_none() { |
|
461 | if self.data.is_none() { | |
399 | return; // moved to another PyLeaked |
|
462 | return; // moved to another PyLeaked | |
400 | } |
|
463 | } | |
401 | self.py_shared_state.decrease_leak_count(py, false); |
|
464 | self.py_shared_state.decrease_leak_count(py, false); | |
402 | } |
|
465 | } | |
403 | } |
|
466 | } | |
404 |
|
467 | |||
405 | /// Immutably borrowed reference to a leaked value. |
|
468 | /// Immutably borrowed reference to a leaked value. | |
406 | pub struct PyLeakedRef<'a, T> { |
|
469 | pub struct PyLeakedRef<'a, T> { | |
407 | _py: Python<'a>, |
|
470 | _py: Python<'a>, | |
408 | data: &'a T, |
|
471 | data: &'a T, | |
409 | } |
|
472 | } | |
410 |
|
473 | |||
411 | impl<T> Deref for PyLeakedRef<'_, T> { |
|
474 | impl<T> Deref for PyLeakedRef<'_, T> { | |
412 | type Target = T; |
|
475 | type Target = T; | |
413 |
|
476 | |||
414 | fn deref(&self) -> &T { |
|
477 | fn deref(&self) -> &T { | |
415 | self.data |
|
478 | self.data | |
416 | } |
|
479 | } | |
417 | } |
|
480 | } | |
418 |
|
481 | |||
419 | /// Mutably borrowed reference to a leaked value. |
|
482 | /// Mutably borrowed reference to a leaked value. | |
420 | pub struct PyLeakedRefMut<'a, T> { |
|
483 | pub struct PyLeakedRefMut<'a, T> { | |
421 | _py: Python<'a>, |
|
484 | _py: Python<'a>, | |
422 | data: &'a mut T, |
|
485 | data: &'a mut T, | |
423 | } |
|
486 | } | |
424 |
|
487 | |||
425 | impl<T> Deref for PyLeakedRefMut<'_, T> { |
|
488 | impl<T> Deref for PyLeakedRefMut<'_, T> { | |
426 | type Target = T; |
|
489 | type Target = T; | |
427 |
|
490 | |||
428 | fn deref(&self) -> &T { |
|
491 | fn deref(&self) -> &T { | |
429 | self.data |
|
492 | self.data | |
430 | } |
|
493 | } | |
431 | } |
|
494 | } | |
432 |
|
495 | |||
433 | impl<T> DerefMut for PyLeakedRefMut<'_, T> { |
|
496 | impl<T> DerefMut for PyLeakedRefMut<'_, T> { | |
434 | fn deref_mut(&mut self) -> &mut T { |
|
497 | fn deref_mut(&mut self) -> &mut T { | |
435 | self.data |
|
498 | self.data | |
436 | } |
|
499 | } | |
437 | } |
|
500 | } | |
438 |
|
501 | |||
439 | /// Defines a `py_class!` that acts as a Python iterator over a Rust iterator. |
|
502 | /// Defines a `py_class!` that acts as a Python iterator over a Rust iterator. | |
440 | /// |
|
503 | /// | |
441 | /// TODO: this is a bit awkward to use, and a better (more complicated) |
|
504 | /// TODO: this is a bit awkward to use, and a better (more complicated) | |
442 | /// procedural macro would simplify the interface a lot. |
|
505 | /// procedural macro would simplify the interface a lot. | |
443 | /// |
|
506 | /// | |
444 | /// # Parameters |
|
507 | /// # Parameters | |
445 | /// |
|
508 | /// | |
446 | /// * `$name` is the identifier to give to the resulting Rust struct. |
|
509 | /// * `$name` is the identifier to give to the resulting Rust struct. | |
447 | /// * `$leaked` corresponds to `$leaked` in the matching `py_shared_ref!` call. |
|
510 | /// * `$leaked` corresponds to `$leaked` in the matching `py_shared_ref!` call. | |
448 | /// * `$iterator_type` is the type of the Rust iterator. |
|
511 | /// * `$iterator_type` is the type of the Rust iterator. | |
449 | /// * `$success_func` is a function for processing the Rust `(key, value)` |
|
512 | /// * `$success_func` is a function for processing the Rust `(key, value)` | |
450 | /// tuple on iteration success, turning it into something Python understands. |
|
513 | /// tuple on iteration success, turning it into something Python understands. | |
451 | /// * `$success_func` is the return type of `$success_func` |
|
514 | /// * `$success_func` is the return type of `$success_func` | |
452 | /// |
|
515 | /// | |
453 | /// # Example |
|
516 | /// # Example | |
454 | /// |
|
517 | /// | |
455 | /// ``` |
|
518 | /// ``` | |
456 | /// struct MyStruct { |
|
519 | /// struct MyStruct { | |
457 | /// inner: HashMap<Vec<u8>, Vec<u8>>; |
|
520 | /// inner: HashMap<Vec<u8>, Vec<u8>>; | |
458 | /// } |
|
521 | /// } | |
459 | /// |
|
522 | /// | |
460 | /// py_class!(pub class MyType |py| { |
|
523 | /// py_class!(pub class MyType |py| { | |
461 | /// data inner: PySharedRefCell<MyStruct>; |
|
524 | /// data inner: PySharedRefCell<MyStruct>; | |
462 | /// |
|
525 | /// | |
463 | /// def __iter__(&self) -> PyResult<MyTypeItemsIterator> { |
|
526 | /// def __iter__(&self) -> PyResult<MyTypeItemsIterator> { | |
464 | /// let leaked_ref = self.inner_shared(py).leak_immutable()?; |
|
527 | /// let leaked_ref = self.inner_shared(py).leak_immutable()?; | |
465 | /// MyTypeItemsIterator::from_inner( |
|
528 | /// MyTypeItemsIterator::from_inner( | |
466 | /// py, |
|
529 | /// py, | |
467 | /// unsafe { leaked_ref.map(py, |o| o.iter()) }, |
|
530 | /// unsafe { leaked_ref.map(py, |o| o.iter()) }, | |
468 | /// ) |
|
531 | /// ) | |
469 | /// } |
|
532 | /// } | |
470 | /// }); |
|
533 | /// }); | |
471 | /// |
|
534 | /// | |
472 | /// impl MyType { |
|
535 | /// impl MyType { | |
473 | /// fn translate_key_value( |
|
536 | /// fn translate_key_value( | |
474 | /// py: Python, |
|
537 | /// py: Python, | |
475 | /// res: (&Vec<u8>, &Vec<u8>), |
|
538 | /// res: (&Vec<u8>, &Vec<u8>), | |
476 | /// ) -> PyResult<Option<(PyBytes, PyBytes)>> { |
|
539 | /// ) -> PyResult<Option<(PyBytes, PyBytes)>> { | |
477 | /// let (f, entry) = res; |
|
540 | /// let (f, entry) = res; | |
478 | /// Ok(Some(( |
|
541 | /// Ok(Some(( | |
479 | /// PyBytes::new(py, f), |
|
542 | /// PyBytes::new(py, f), | |
480 | /// PyBytes::new(py, entry), |
|
543 | /// PyBytes::new(py, entry), | |
481 | /// ))) |
|
544 | /// ))) | |
482 | /// } |
|
545 | /// } | |
483 | /// } |
|
546 | /// } | |
484 | /// |
|
547 | /// | |
485 | /// py_shared_ref!(MyType, MyStruct, inner, MyTypeLeakedRef); |
|
548 | /// py_shared_ref!(MyType, MyStruct, inner, MyTypeLeakedRef); | |
486 | /// |
|
549 | /// | |
487 | /// py_shared_iterator!( |
|
550 | /// py_shared_iterator!( | |
488 | /// MyTypeItemsIterator, |
|
551 | /// MyTypeItemsIterator, | |
489 | /// PyLeaked<HashMap<'static, Vec<u8>, Vec<u8>>>, |
|
552 | /// PyLeaked<HashMap<'static, Vec<u8>, Vec<u8>>>, | |
490 | /// MyType::translate_key_value, |
|
553 | /// MyType::translate_key_value, | |
491 | /// Option<(PyBytes, PyBytes)> |
|
554 | /// Option<(PyBytes, PyBytes)> | |
492 | /// ); |
|
555 | /// ); | |
493 | /// ``` |
|
556 | /// ``` | |
494 | macro_rules! py_shared_iterator { |
|
557 | macro_rules! py_shared_iterator { | |
495 | ( |
|
558 | ( | |
496 | $name: ident, |
|
559 | $name: ident, | |
497 | $leaked: ty, |
|
560 | $leaked: ty, | |
498 | $success_func: expr, |
|
561 | $success_func: expr, | |
499 | $success_type: ty |
|
562 | $success_type: ty | |
500 | ) => { |
|
563 | ) => { | |
501 | py_class!(pub class $name |py| { |
|
564 | py_class!(pub class $name |py| { | |
502 | data inner: RefCell<Option<$leaked>>; |
|
565 | data inner: RefCell<Option<$leaked>>; | |
503 |
|
566 | |||
504 | def __next__(&self) -> PyResult<$success_type> { |
|
567 | def __next__(&self) -> PyResult<$success_type> { | |
505 | let mut inner_opt = self.inner(py).borrow_mut(); |
|
568 | let mut inner_opt = self.inner(py).borrow_mut(); | |
506 | if let Some(leaked) = inner_opt.as_mut() { |
|
569 | if let Some(leaked) = inner_opt.as_mut() { | |
507 | let mut iter = leaked.try_borrow_mut(py)?; |
|
570 | let mut iter = leaked.try_borrow_mut(py)?; | |
508 | match iter.next() { |
|
571 | match iter.next() { | |
509 | None => { |
|
572 | None => { | |
510 | // replace Some(inner) by None, drop $leaked |
|
573 | // replace Some(inner) by None, drop $leaked | |
511 | inner_opt.take(); |
|
574 | inner_opt.take(); | |
512 | Ok(None) |
|
575 | Ok(None) | |
513 | } |
|
576 | } | |
514 | Some(res) => { |
|
577 | Some(res) => { | |
515 | $success_func(py, res) |
|
578 | $success_func(py, res) | |
516 | } |
|
579 | } | |
517 | } |
|
580 | } | |
518 | } else { |
|
581 | } else { | |
519 | Ok(None) |
|
582 | Ok(None) | |
520 | } |
|
583 | } | |
521 | } |
|
584 | } | |
522 |
|
585 | |||
523 | def __iter__(&self) -> PyResult<Self> { |
|
586 | def __iter__(&self) -> PyResult<Self> { | |
524 | Ok(self.clone_ref(py)) |
|
587 | Ok(self.clone_ref(py)) | |
525 | } |
|
588 | } | |
526 | }); |
|
589 | }); | |
527 |
|
590 | |||
528 | impl $name { |
|
591 | impl $name { | |
529 | pub fn from_inner( |
|
592 | pub fn from_inner( | |
530 | py: Python, |
|
593 | py: Python, | |
531 | leaked: $leaked, |
|
594 | leaked: $leaked, | |
532 | ) -> PyResult<Self> { |
|
595 | ) -> PyResult<Self> { | |
533 | Self::create_instance( |
|
596 | Self::create_instance( | |
534 | py, |
|
597 | py, | |
535 | RefCell::new(Some(leaked)), |
|
598 | RefCell::new(Some(leaked)), | |
536 | ) |
|
599 | ) | |
537 | } |
|
600 | } | |
538 | } |
|
601 | } | |
539 | }; |
|
602 | }; | |
540 | } |
|
603 | } | |
541 |
|
604 | |||
542 | #[cfg(test)] |
|
605 | #[cfg(test)] | |
543 | #[cfg(any(feature = "python27-bin", feature = "python3-bin"))] |
|
606 | #[cfg(any(feature = "python27-bin", feature = "python3-bin"))] | |
544 | mod test { |
|
607 | mod test { | |
545 | use super::*; |
|
608 | use super::*; | |
546 | use cpython::{GILGuard, Python}; |
|
609 | use cpython::{GILGuard, Python}; | |
547 |
|
610 | |||
548 | py_class!(class Owner |py| { |
|
611 | py_class!(class Owner |py| { | |
549 | data string: PySharedRefCell<String>; |
|
612 | data string: PySharedRefCell<String>; | |
550 | }); |
|
613 | }); | |
551 | py_shared_ref!(Owner, String, string, string_shared); |
|
614 | py_shared_ref!(Owner, String, string, string_shared); | |
552 |
|
615 | |||
553 | fn prepare_env() -> (GILGuard, Owner) { |
|
616 | fn prepare_env() -> (GILGuard, Owner) { | |
554 | let gil = Python::acquire_gil(); |
|
617 | let gil = Python::acquire_gil(); | |
555 | let py = gil.python(); |
|
618 | let py = gil.python(); | |
556 | let owner = |
|
619 | let owner = | |
557 | Owner::create_instance(py, PySharedRefCell::new("new".to_owned())) |
|
620 | Owner::create_instance(py, PySharedRefCell::new("new".to_owned())) | |
558 | .unwrap(); |
|
621 | .unwrap(); | |
559 | (gil, owner) |
|
622 | (gil, owner) | |
560 | } |
|
623 | } | |
561 |
|
624 | |||
562 | #[test] |
|
625 | #[test] | |
563 | fn test_leaked_borrow() { |
|
626 | fn test_leaked_borrow() { | |
564 | let (gil, owner) = prepare_env(); |
|
627 | let (gil, owner) = prepare_env(); | |
565 | let py = gil.python(); |
|
628 | let py = gil.python(); | |
566 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); |
|
629 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); | |
567 | let leaked_ref = leaked.try_borrow(py).unwrap(); |
|
630 | let leaked_ref = leaked.try_borrow(py).unwrap(); | |
568 | assert_eq!(*leaked_ref, "new"); |
|
631 | assert_eq!(*leaked_ref, "new"); | |
569 | } |
|
632 | } | |
570 |
|
633 | |||
571 | #[test] |
|
634 | #[test] | |
572 | fn test_leaked_borrow_mut() { |
|
635 | fn test_leaked_borrow_mut() { | |
573 | let (gil, owner) = prepare_env(); |
|
636 | let (gil, owner) = prepare_env(); | |
574 | let py = gil.python(); |
|
637 | let py = gil.python(); | |
575 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); |
|
638 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); | |
576 | let mut leaked_iter = unsafe { leaked.map(py, |s| s.chars()) }; |
|
639 | let mut leaked_iter = unsafe { leaked.map(py, |s| s.chars()) }; | |
577 | let mut leaked_ref = leaked_iter.try_borrow_mut(py).unwrap(); |
|
640 | let mut leaked_ref = leaked_iter.try_borrow_mut(py).unwrap(); | |
578 | assert_eq!(leaked_ref.next(), Some('n')); |
|
641 | assert_eq!(leaked_ref.next(), Some('n')); | |
579 | assert_eq!(leaked_ref.next(), Some('e')); |
|
642 | assert_eq!(leaked_ref.next(), Some('e')); | |
580 | assert_eq!(leaked_ref.next(), Some('w')); |
|
643 | assert_eq!(leaked_ref.next(), Some('w')); | |
581 | assert_eq!(leaked_ref.next(), None); |
|
644 | assert_eq!(leaked_ref.next(), None); | |
582 | } |
|
645 | } | |
583 |
|
646 | |||
584 | #[test] |
|
647 | #[test] | |
|
648 | fn test_leaked_borrow_after_mut() { | |||
|
649 | let (gil, owner) = prepare_env(); | |||
|
650 | let py = gil.python(); | |||
|
651 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); | |||
|
652 | owner.string(py).py_shared_state.leak_count.replace(0); // XXX cheat | |||
|
653 | owner.string_shared(py).borrow_mut().unwrap().clear(); | |||
|
654 | owner.string(py).py_shared_state.leak_count.replace(1); // XXX cheat | |||
|
655 | assert!(leaked.try_borrow(py).is_err()); | |||
|
656 | } | |||
|
657 | ||||
|
658 | #[test] | |||
|
659 | fn test_leaked_borrow_mut_after_mut() { | |||
|
660 | let (gil, owner) = prepare_env(); | |||
|
661 | let py = gil.python(); | |||
|
662 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); | |||
|
663 | let mut leaked_iter = unsafe { leaked.map(py, |s| s.chars()) }; | |||
|
664 | owner.string(py).py_shared_state.leak_count.replace(0); // XXX cheat | |||
|
665 | owner.string_shared(py).borrow_mut().unwrap().clear(); | |||
|
666 | owner.string(py).py_shared_state.leak_count.replace(1); // XXX cheat | |||
|
667 | assert!(leaked_iter.try_borrow_mut(py).is_err()); | |||
|
668 | } | |||
|
669 | ||||
|
670 | #[test] | |||
|
671 | #[should_panic(expected = "map() over invalidated leaked reference")] | |||
|
672 | fn test_leaked_map_after_mut() { | |||
|
673 | let (gil, owner) = prepare_env(); | |||
|
674 | let py = gil.python(); | |||
|
675 | let leaked = owner.string_shared(py).leak_immutable().unwrap(); | |||
|
676 | owner.string(py).py_shared_state.leak_count.replace(0); // XXX cheat | |||
|
677 | owner.string_shared(py).borrow_mut().unwrap().clear(); | |||
|
678 | owner.string(py).py_shared_state.leak_count.replace(1); // XXX cheat | |||
|
679 | let _leaked_iter = unsafe { leaked.map(py, |s| s.chars()) }; | |||
|
680 | } | |||
|
681 | ||||
|
682 | #[test] | |||
585 | fn test_borrow_mut_while_leaked() { |
|
683 | fn test_borrow_mut_while_leaked() { | |
586 | let (gil, owner) = prepare_env(); |
|
684 | let (gil, owner) = prepare_env(); | |
587 | let py = gil.python(); |
|
685 | let py = gil.python(); | |
588 | assert!(owner.string_shared(py).borrow_mut().is_ok()); |
|
686 | assert!(owner.string_shared(py).borrow_mut().is_ok()); | |
589 | let _leaked = owner.string_shared(py).leak_immutable().unwrap(); |
|
687 | let _leaked = owner.string_shared(py).leak_immutable().unwrap(); | |
590 | // TODO: will be allowed |
|
688 | // TODO: will be allowed | |
591 | assert!(owner.string_shared(py).borrow_mut().is_err()); |
|
689 | assert!(owner.string_shared(py).borrow_mut().is_err()); | |
592 | } |
|
690 | } | |
593 | } |
|
691 | } |
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