rusqlite/
limits.rs

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
//! Run-Time Limits

use crate::{ffi, Connection};
use std::os::raw::c_int;

/// Run-Time limit categories, for use with [`Connection::limit`] and
/// [`Connection::set_limit`].
///
/// See the official documentation for more information:
/// - <https://www.sqlite.org/c3ref/c_limit_attached.html>
/// - <https://www.sqlite.org/limits.html>
#[derive(Copy, Clone, Debug)]
#[repr(i32)]
#[non_exhaustive]
#[allow(clippy::upper_case_acronyms, non_camel_case_types)]
#[cfg_attr(docsrs, doc(cfg(feature = "limits")))]
pub enum Limit {
    /// The maximum size of any string or BLOB or table row, in bytes.
    SQLITE_LIMIT_LENGTH = ffi::SQLITE_LIMIT_LENGTH,
    /// The maximum length of an SQL statement, in bytes.
    SQLITE_LIMIT_SQL_LENGTH = ffi::SQLITE_LIMIT_SQL_LENGTH,
    /// The maximum number of columns in a table definition or in the result set
    /// of a SELECT or the maximum number of columns in an index or in an
    /// ORDER BY or GROUP BY clause.
    SQLITE_LIMIT_COLUMN = ffi::SQLITE_LIMIT_COLUMN,
    /// The maximum depth of the parse tree on any expression.
    SQLITE_LIMIT_EXPR_DEPTH = ffi::SQLITE_LIMIT_EXPR_DEPTH,
    /// The maximum number of terms in a compound SELECT statement.
    SQLITE_LIMIT_COMPOUND_SELECT = ffi::SQLITE_LIMIT_COMPOUND_SELECT,
    /// The maximum number of instructions in a virtual machine program used to
    /// implement an SQL statement.
    SQLITE_LIMIT_VDBE_OP = ffi::SQLITE_LIMIT_VDBE_OP,
    /// The maximum number of arguments on a function.
    SQLITE_LIMIT_FUNCTION_ARG = ffi::SQLITE_LIMIT_FUNCTION_ARG,
    /// The maximum number of attached databases.
    SQLITE_LIMIT_ATTACHED = ffi::SQLITE_LIMIT_ATTACHED,
    /// The maximum length of the pattern argument to the LIKE or GLOB
    /// operators.
    SQLITE_LIMIT_LIKE_PATTERN_LENGTH = ffi::SQLITE_LIMIT_LIKE_PATTERN_LENGTH,
    /// The maximum index number of any parameter in an SQL statement.
    SQLITE_LIMIT_VARIABLE_NUMBER = ffi::SQLITE_LIMIT_VARIABLE_NUMBER,
    /// The maximum depth of recursion for triggers.
    SQLITE_LIMIT_TRIGGER_DEPTH = ffi::SQLITE_LIMIT_TRIGGER_DEPTH,
    /// The maximum number of auxiliary worker threads that a single prepared
    /// statement may start.
    SQLITE_LIMIT_WORKER_THREADS = ffi::SQLITE_LIMIT_WORKER_THREADS,
}

impl Connection {
    /// Returns the current value of a [`Limit`].
    #[inline]
    #[cfg_attr(docsrs, doc(cfg(feature = "limits")))]
    pub fn limit(&self, limit: Limit) -> i32 {
        let c = self.db.borrow();
        unsafe { ffi::sqlite3_limit(c.db(), limit as c_int, -1) }
    }

    /// Changes the [`Limit`] to `new_val`, returning the prior
    /// value of the limit.
    #[inline]
    #[cfg_attr(docsrs, doc(cfg(feature = "limits")))]
    pub fn set_limit(&self, limit: Limit, new_val: i32) -> i32 {
        let c = self.db.borrow_mut();
        unsafe { ffi::sqlite3_limit(c.db(), limit as c_int, new_val) }
    }
}

#[cfg(test)]
mod test {
    use super::*;
    use crate::Result;

    #[test]
    fn test_limit_values() {
        assert_eq!(Limit::SQLITE_LIMIT_LENGTH as i32, ffi::SQLITE_LIMIT_LENGTH,);
        assert_eq!(
            Limit::SQLITE_LIMIT_SQL_LENGTH as i32,
            ffi::SQLITE_LIMIT_SQL_LENGTH,
        );
        assert_eq!(Limit::SQLITE_LIMIT_COLUMN as i32, ffi::SQLITE_LIMIT_COLUMN,);
        assert_eq!(
            Limit::SQLITE_LIMIT_EXPR_DEPTH as i32,
            ffi::SQLITE_LIMIT_EXPR_DEPTH,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_COMPOUND_SELECT as i32,
            ffi::SQLITE_LIMIT_COMPOUND_SELECT,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_VDBE_OP as i32,
            ffi::SQLITE_LIMIT_VDBE_OP,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_FUNCTION_ARG as i32,
            ffi::SQLITE_LIMIT_FUNCTION_ARG,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_ATTACHED as i32,
            ffi::SQLITE_LIMIT_ATTACHED,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_LIKE_PATTERN_LENGTH as i32,
            ffi::SQLITE_LIMIT_LIKE_PATTERN_LENGTH,
        );
        assert_eq!(
            Limit::SQLITE_LIMIT_VARIABLE_NUMBER as i32,
            ffi::SQLITE_LIMIT_VARIABLE_NUMBER,
        );
        #[cfg(feature = "bundled")]
        assert_eq!(
            Limit::SQLITE_LIMIT_TRIGGER_DEPTH as i32,
            ffi::SQLITE_LIMIT_TRIGGER_DEPTH,
        );
        #[cfg(feature = "bundled")]
        assert_eq!(
            Limit::SQLITE_LIMIT_WORKER_THREADS as i32,
            ffi::SQLITE_LIMIT_WORKER_THREADS,
        );
    }

    #[test]
    fn test_limit() -> Result<()> {
        let db = Connection::open_in_memory()?;
        db.set_limit(Limit::SQLITE_LIMIT_LENGTH, 1024);
        assert_eq!(1024, db.limit(Limit::SQLITE_LIMIT_LENGTH));

        db.set_limit(Limit::SQLITE_LIMIT_SQL_LENGTH, 1024);
        assert_eq!(1024, db.limit(Limit::SQLITE_LIMIT_SQL_LENGTH));

        db.set_limit(Limit::SQLITE_LIMIT_COLUMN, 64);
        assert_eq!(64, db.limit(Limit::SQLITE_LIMIT_COLUMN));

        db.set_limit(Limit::SQLITE_LIMIT_EXPR_DEPTH, 256);
        assert_eq!(256, db.limit(Limit::SQLITE_LIMIT_EXPR_DEPTH));

        db.set_limit(Limit::SQLITE_LIMIT_COMPOUND_SELECT, 32);
        assert_eq!(32, db.limit(Limit::SQLITE_LIMIT_COMPOUND_SELECT));

        db.set_limit(Limit::SQLITE_LIMIT_FUNCTION_ARG, 32);
        assert_eq!(32, db.limit(Limit::SQLITE_LIMIT_FUNCTION_ARG));

        db.set_limit(Limit::SQLITE_LIMIT_ATTACHED, 2);
        assert_eq!(2, db.limit(Limit::SQLITE_LIMIT_ATTACHED));

        db.set_limit(Limit::SQLITE_LIMIT_LIKE_PATTERN_LENGTH, 128);
        assert_eq!(128, db.limit(Limit::SQLITE_LIMIT_LIKE_PATTERN_LENGTH));

        db.set_limit(Limit::SQLITE_LIMIT_VARIABLE_NUMBER, 99);
        assert_eq!(99, db.limit(Limit::SQLITE_LIMIT_VARIABLE_NUMBER));

        db.set_limit(Limit::SQLITE_LIMIT_TRIGGER_DEPTH, 32);
        assert_eq!(32, db.limit(Limit::SQLITE_LIMIT_TRIGGER_DEPTH));

        db.set_limit(Limit::SQLITE_LIMIT_WORKER_THREADS, 2);
        assert_eq!(2, db.limit(Limit::SQLITE_LIMIT_WORKER_THREADS));
        Ok(())
    }
}