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
162
163
164
165
166
167
168

//! Configuration management.


use crate::common::errors::Error;
use std::fs::OpenOptions;
use std::io::{BufRead, BufReader};
use std::sync::Arc;
use std::sync::Mutex;
use std::sync::MutexGuard;
use log::warn;


#[derive(Clone)]
/// Global configuration with multithreading support.
pub struct ConfigMt {
    conf: Arc<Mutex<Config>>,
}

impl ConfigMt {
    /// Create a new configuration instance.
    pub fn new() -> ConfigMt {
        ConfigMt {
            conf: Arc::new(Mutex::new(Config::new()))
        }
    }

    /// Lock and return configration for reading or modification.
    pub fn get_conf(&self) -> MutexGuard<Config> {
        self.conf.lock().unwrap()
    }
}

macro_rules! gen_config {
    ( $( $name:ident, $data_type:ty, $default_val:expr, $get_fn:ident, $set_fn:ident, $str_name:literal, $conv_fn:path ), *) => {
        /// Struct to access configuration values.
        pub struct Config {
            $(
                $name: $data_type,
            )*
        }

        impl Config {
        
            /// Create a new configuration instance.
            pub fn new() -> Config {
                Config {
                    $(
                        $name: $default_val, 
                    )*
                }
            }

            $(
                /// Get value of a parameter.
                pub fn $get_fn(&self) -> &$data_type {
                    &self.$name
                }

                /// Set value of a parameter.
                pub fn $set_fn(&mut self, $name: $data_type) {
                    self.$name = $name;
                }
            )*

            fn process_config_file_entry(&mut self, name: &str, val: &str) -> Result<(), Error> {

                match name {
                    $(
                        $str_name => { self.$name = $conv_fn(val)?; },
                    )*
                    _ => warn!("Skipping unexpected config entry: {}", name)
                };

                Ok(())
            }
        }
    }
}


impl Config {

    /// Load configuration from a file.
    pub fn load(&mut self, file_path: &str) -> Result<(), Error> {
        let f = BufReader::new(OpenOptions::new()
            .create(false)
            .write(false)
            .read(true)
            .truncate(false)
            .open(file_path)?);

        for line in f.lines() {
            if let Ok(line) = line {
                if let Ok((name, val)) = Self::process_config_file_line(&line) {
                    self.process_config_file_entry(name, val)?;
                }
            }
        }

        Ok(())
    }

    fn process_config_file_line<'a>(s: &'a str) -> Result<(&'a str, &'a str), ()> {
        let line = s.as_bytes();
        let mut p = 0;

        // skip space
        while line[p] == b' ' || line[p] == b'\t' { p += 1; };

        // check for comment line
        if line[p] == b'#' { return Err(()) }

        // read 'name' part
        let p1 = p;
        while (line[p] >= b'a' && line[p] <= b'z') 
            || (line[p] >= b'A' && line[p] <= b'Z')
            || (line[p] >= b'0' && line[p] <= b'9')
            || line[p] == b'_' || line[p] == b'-' 
        {
                p+= 1;
        }
        if p == p1 { return Err(()) }
        let p2 = p;

        // read '='
        while line[p] == b' ' || line[p] == b'\t' { p += 1; };
        if line[p] != b'=' { return Err(()) }
        while line[p] == b' ' || line[p] == b'\t' { p += 1; };

        // return 'name' and 'val'
        Ok((&s[p1..p2], &s[p..]))
    }

    fn load_string(value: &str) -> Result<String, Error> {
        Ok(String::from(value))
    }

    fn load_u32_val(value: &str) -> Result<u32, Error> {
        let ret = str::parse::<u32>(value)?;
        Ok(ret)
    }

    fn load_u64_val(value: &str) -> Result<u64, Error> {
        let ret = str::parse::<u64>(value)?;
        Ok(ret)
    }
}

gen_config![log_dir,            String, "trnlog".to_owned(),    get_log_dir,                   set_log_dir,                   "log_dir", Config::load_string,
    datastore_path,             String, ".".to_owned(),         get_datastore_path,            set_datastore_path,            "datastore_path", Config::load_string,
    max_log_file_size,          u32,    10*1024*1024,           get_max_log_file_size,         set_max_log_file_size,         "max_log_file_size", Config::load_u32_val,
    log_writer_buf_size,        u32,    1048576,                get_log_writer_buf_size,       set_log_writer_buf_size,       "log_writer_buf_size", Config::load_u32_val,
    tran_mgr_n_buckets,         u32,    128,                    get_tran_mgr_n_buckets,        set_tran_mgr_n_buckets,        "tran_mgr_n_buckets", Config::load_u32_val,
    tran_mgr_n_tran,            u32,    1024,                   get_tran_mgr_n_tran,           set_tran_mgr_n_tran,           "tran_mgr_n_tran", Config::load_u32_val,
    tran_mgr_n_obj_buckets,     u32,    128,                    get_tran_mgr_n_obj_buckets,    set_tran_mgr_n_obj_buckets,    "tran_mgr_n_obj_buckets", Config::load_u32_val,
    tran_mgr_n_obj_lock,        u32,    1024,                   get_tran_mgr_n_obj_lock,       set_tran_mgr_n_obj_lock,       "tran_mgr_n_obj_lock", Config::load_u32_val,
    block_mgr_n_lock,           u32,    1024,                   get_block_mgr_n_lock,          set_block_mgr_n_lock,          "block_mgr_n_lock", Config::load_u32_val,
    free_info_n_file_lock,      u32,    16,                     get_free_info_n_file_lock,     set_free_info_n_file_lock,     "free_info_n_file_lock", Config::load_u32_val,
    free_info_n_extent_lock,    u32,    128,                    get_free_info_n_extent_lock,   set_free_info_n_extent_lock,   "free_info_n_extent_lock", Config::load_u32_val,
    block_buf_size,             u64,    32*1024*1024,           get_block_buf_size,            set_block_buf_size,            "block_buf_size", Config::load_u64_val,
    checkpoint_data_threshold,  u64,    10*1024*1024,           get_checkpoint_data_threshold, set_checkpoint_data_threshold, "checkpoint_data_threshold", Config::load_u64_val,
    version_retain_time,        u32,    3600,                   get_version_retain_time,       set_version_retain_time,       "version_retain_time", Config::load_u32_val,
    block_fill_ratio,           u32,    80,                     get_block_fill_ratio,          set_block_fill_ratio,          "block_fill_ratio", Config::load_u32_val,
    writer_num,                 u32,    2,                      get_writer_num,                set_writer_num,                "writer_num", Config::load_u32_val];