summaryrefslogtreecommitdiffstats
path: root/services/sync/golden_gate/src/log.rs
blob: de7fd0dfc393f9771a7c88871fe47d350c3801ba (plain)
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
159
160
161
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

use std::fmt::{self, Write};

use log::{Level, LevelFilter, Log, Metadata, Record};
use moz_task::{Task, TaskRunnable, ThreadPtrHandle, ThreadPtrHolder};
use nserror::nsresult;
use nsstring::nsString;
use xpcom::{interfaces::mozIServicesLogSink, RefPtr};

pub struct LogSink {
    pub max_level: LevelFilter,
    logger: Option<ThreadPtrHandle<mozIServicesLogSink>>,
}

impl Default for LogSink {
    fn default() -> Self {
        LogSink {
            max_level: LevelFilter::Off,
            logger: None,
        }
    }
}

impl LogSink {
    /// Creates a log sink that adapts the Rust `log` crate to the Sync
    /// `Log.sys.mjs` logger.
    ///
    /// This is copied from `bookmark_sync::Logger`. It would be nice to share
    /// these, but, for now, we've just duplicated it to make prototyping
    /// easier.
    #[inline]
    pub fn new(max_level: LevelFilter, logger: ThreadPtrHandle<mozIServicesLogSink>) -> LogSink {
        LogSink {
            max_level,
            logger: Some(logger),
        }
    }

    /// Creates a log sink using the given Services `logger` as the
    /// underlying implementation. The `logger` will always be called
    /// asynchronously on its owning thread; it doesn't need to be
    /// thread-safe.
    pub fn with_logger(logger: Option<&mozIServicesLogSink>) -> Result<LogSink, nsresult> {
        Ok(if let Some(logger) = logger {
            // Fetch the maximum log level while we're on the main thread, so
            // that `LogSink::enabled()` can check it while on the background
            // thread. Otherwise, we'd need to dispatch a `LogTask` for every
            // log message, only to discard most of them when the task calls
            // into the logger on the main thread.
            let mut raw_max_level = 0i16;
            let rv = unsafe { logger.GetMaxLevel(&mut raw_max_level) };
            let max_level = if rv.succeeded() {
                match raw_max_level {
                    mozIServicesLogSink::LEVEL_ERROR => LevelFilter::Error,
                    mozIServicesLogSink::LEVEL_WARN => LevelFilter::Warn,
                    mozIServicesLogSink::LEVEL_DEBUG => LevelFilter::Debug,
                    mozIServicesLogSink::LEVEL_TRACE => LevelFilter::Trace,
                    mozIServicesLogSink::LEVEL_INFO => LevelFilter::Info,
                    _ => LevelFilter::Off,
                }
            } else {
                LevelFilter::Off
            };
            LogSink::new(
                max_level,
                ThreadPtrHolder::new(cstr!("mozIServicesLogSink"), RefPtr::new(logger))?,
            )
        } else {
            LogSink::default()
        })
    }

    /// Returns a reference to the underlying `mozIServicesLogSink`.
    pub fn logger(&self) -> Option<&mozIServicesLogSink> {
        self.logger.as_ref().and_then(|l| l.get())
    }

    /// Logs a message to the Sync logger, if one is set. This would be better
    /// implemented as a macro, as Dogear does, so that we can pass variadic
    /// arguments without manually invoking `fmt_args!()` every time we want
    /// to log a message.
    ///
    /// The `log` crate's macros aren't suitable here, because those log to the
    /// global logger. However, we don't want to set the global logger in our
    /// crate, because that will log _everything_ that uses the Rust `log` crate
    /// to the Sync logs, including WebRender and audio logging.
    pub fn debug(&self, args: fmt::Arguments) {
        let meta = Metadata::builder()
            .level(Level::Debug)
            .target(module_path!())
            .build();
        if self.enabled(&meta) {
            self.log(&Record::builder().args(args).metadata(meta).build());
        }
    }
}

impl Log for LogSink {
    #[inline]
    fn enabled(&self, meta: &Metadata) -> bool {
        self.logger.is_some() && meta.level() <= self.max_level
    }

    fn log(&self, record: &Record) {
        if !self.enabled(record.metadata()) {
            return;
        }
        if let Some(logger) = &self.logger {
            let mut message = nsString::new();
            if write!(message, "{}", record.args()).is_ok() {
                let task = LogTask {
                    logger: logger.clone(),
                    level: record.metadata().level(),
                    message,
                };
                let _ = TaskRunnable::new("extension_storage_sync::Logger::log", Box::new(task))
                    .and_then(|r| TaskRunnable::dispatch(r, logger.owning_thread()));
            }
        }
    }

    fn flush(&self) {}
}

/// Logs a message to the mirror logger. This task is created on the background
/// thread queue, and dispatched to the main thread.
struct LogTask {
    logger: ThreadPtrHandle<mozIServicesLogSink>,
    level: Level,
    message: nsString,
}

impl Task for LogTask {
    fn run(&self) {
        let logger = self.logger.get().unwrap();
        match self.level {
            Level::Error => unsafe {
                logger.Error(&*self.message);
            },
            Level::Warn => unsafe {
                logger.Warn(&*self.message);
            },
            Level::Debug => unsafe {
                logger.Debug(&*self.message);
            },
            Level::Trace => unsafe {
                logger.Trace(&*self.message);
            },
            Level::Info => unsafe {
                logger.Info(&*self.message);
            },
        }
    }

    fn done(&self) -> Result<(), nsresult> {
        Ok(())
    }
}