librpm 0.2.0

RPM Package Manager library binding with an idiomatic Rust API
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

/*
 * Copyright (C) RustRPM Developers
 *
 * Licensed under the Mozilla Public License Version 2.0
 * Fedora-License-Identifier: MPLv2.0
 * SPDX-2.0-License-Identifier: MPL-2.0
 * SPDX-3.0-License-Identifier: MPL-2.0
 *
 * This is free software.
 * For more information on the license, see LICENSE.
 * For more information on free software, see <https://www.gnu.org/philosophy/free-sw.en.html>.
 *
 * 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 <https://mozilla.org/MPL/2.0/>.
 */

//! Support for configuring RPM, i.e. reading configuration files

use crate::error::{Error, ErrorKind};
use crate::internal::ConfigState;
use crate::macro_context::MacroContext;
use std::ffi::CString;
use std::os::unix::ffi::OsStrExt;
use std::path::Path;
use std::ptr;

/// Name of the macro which defines the path to the database
const DB_PATH_MACRO: &str = "_dbpath";

/// Read RPM configuration (a.k.a. rpmrc).
///
/// If `None` is passed, the default configuration will be used.
///
/// Configuration is global to the process; this function can only be called
/// once.
pub(crate) fn read_file(config_file: Option<&Path>) -> Result<(), Error> {
    let mut global_state = ConfigState::lock();

    // Avoid invoking `rpmReadConfigFiles` more than once. This vicariously
    // invokes `rpmInitCrypto` which causes segfaults (NULL struct pointer
    // derefs) if invoked more than once.
    if global_state.configured {
        fail!(ErrorKind::Config, "already configured");
    }

    let rc = match config_file {
        Some(path) => {
            if !path.exists() {
                fail!(ErrorKind::Config, "no such file: {}", path.display())
            }

            let cstr = CString::new(path.as_os_str().as_bytes()).map_err(|e| {
                format_err!(
                    ErrorKind::InvalidArg,
                    "invalid path: {} ({})",
                    path.display(),
                    e
                )
            })?;

            unsafe { librpm_sys::rpmReadConfigFiles(cstr.as_ptr(), ptr::null()) }
        }
        None => unsafe { librpm_sys::rpmReadConfigFiles(ptr::null(), ptr::null()) },
    };

    if rc != 0 {
        match config_file {
            Some(path) => fail!(
                ErrorKind::Config,
                "error reading RPM config from: {}",
                path.display()
            ),
            None => fail!(
                ErrorKind::Config,
                "error reading RPM config from default location"
            ),
        }
    }

    global_state.configured = true;

    Ok(())
}

/// Set the path to the global RPM database.
pub(crate) fn set_db_path(path: &Path) -> Result<(), Error> {
    MacroContext::default().define(&format!("{} {}", DB_PATH_MACRO, path.display()), 0)
}