melib/utils: add fnmatch(3) interface

Meant for use with mailbox path globbing.

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

Cargo.lock

@@ -1368,6 +1368,7 @@ dependencies = [
  "async-io",
  "base64 0.13.1",
  "bitflags 2.6.0",
+ "cfg-if",
  "chrono",
  "data-encoding",
  "encoding",

melib/Cargo.toml

@@ -22,6 +22,7 @@ async-fn-stream = { version = "=0.2.2" }
 async-io = { version = "2" }
 base64 = { version = "^0.13", optional = true }
 bitflags = { version = "2.4", features = ["serde"] }
+cfg-if = { version = "^1.0.0" }
 chrono = { version = "^0.4", default-features = false }
 data-encoding = { version = "2.1.1" }
 encoding = { version = "0.2.33", default-features = false }

melib/src/utils/fnmatch.rs

@@ -0,0 +1,77 @@
+//
+// meli
+//
+// Copyright 2024 Emmanouil Pitsidianakis <manos@pitsidianak.is>
+//
+// This file is part of meli.
+//
+// meli is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+//
+// meli is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+//
+// You should have received a copy of the GNU General Public License
+// along with meli. If not, see <http://www.gnu.org/licenses/>.
+//
+// SPDX-License-Identifier: EUPL-1.2 OR GPL-3.0-or-later
+
+//! Interface for `libc`'s `fnmatch(3)`.
+
+use std::ffi::CString;
+
+mod ffi {
+    #![allow(dead_code)]
+
+    use std::os::raw::{c_char, c_int};
+
+    use cfg_if::cfg_if;
+
+    pub(super) const FNM_PERIOD: c_int = 1 << 2;
+    pub(super) const FNM_CASEFOLD: c_int = 1 << 4;
+    pub(super) const FNM_NOMATCH: c_int = 1;
+
+    cfg_if! {
+        if #[cfg(any(
+                target_os = "macos",
+                target_os = "freebsd",
+                target_os = "android",
+        ))] {
+            pub(super) const FNM_PATHNAME: c_int = 1 << 1;
+            pub(super) const FNM_NOESCAPE: c_int = 1 << 0;
+        } else {
+            pub(super) const FNM_PATHNAME: c_int = 1 << 0;
+            pub(super) const FNM_NOESCAPE: c_int = 1 << 1;
+        }
+    }
+
+    extern "C" {
+        pub(super) fn fnmatch(pattern: *const c_char, name: *const c_char, flags: c_int) -> c_int;
+    }
+}
+
+/// See `fnmatch(3)`.
+pub trait Fnmatch {
+    /// Returns `true` if glob pattern argument matches `self`.
+    fn fnmatches(&self, pattern: &str) -> bool;
+}
+
+impl Fnmatch for str {
+    fn fnmatches(&self, pattern: &str) -> bool {
+        let (Ok(name_c), Ok(pattern_c)) = (CString::new(self), CString::new(pattern)) else {
+            return false;
+        };
+        // SAFETY: both `pattern_c` and `name_c` are valid and NULL-terminated.
+        unsafe {
+            ffi::fnmatch(
+                pattern_c.as_c_str().as_ptr(),
+                name_c.as_c_str().as_ptr(),
+                ffi::FNM_PERIOD,
+            ) == 0
+        }
+    }
+}

melib/src/utils/mod.rs

@@ -23,6 +23,7 @@
 
 pub mod connections;
 pub mod datetime;
+pub mod fnmatch;
 pub mod futures;
 pub mod random;
 pub mod vobject;

melib/src/utils/tests.rs

@@ -334,3 +334,42 @@ fn test_fd_locks() {
         )
         .unwrap();
 }
+
+#[test]
+fn test_fnmatch() {
+    use crate::utils::fnmatch::*;
+
+    for n in [
+        "INBOX",
+        "Folder",
+        "Something/with/separator",
+        "local.group.name",
+    ] {
+        assert!(n.fnmatches("*"), "`*` should match with {:?}", n);
+    }
+
+    assert!(!".leading.period".fnmatches("*"));
+    assert!("INBOX/Sent".fnmatches("INBOX/*"));
+    assert!("INBOX/nested/mailbox".fnmatches("INBOX/*"));
+    assert!(!"INBOX".fnmatches("INBOX/*"));
+    assert!(!"Other".fnmatches("INBOX/*"));
+
+    assert!("nntp.taxonomy.niche".fnmatches("nntp.taxonomy.*"));
+    assert!(!"nntp.other".fnmatches("nntp.taxonomy.*"));
+    assert!("all.nested.niche".fnmatches("all.*"));
+
+    for n in ["Archives/2012", "Archives/2015"] {
+        assert!(
+            n.fnmatches("Archives/201?"),
+            "`Archives/201?` should match with {:?}",
+            n
+        );
+    }
+    for n in ["Archives/2005", "Archives/2021"] {
+        assert!(
+            !n.fnmatches("Archives/201?"),
+            "`Archives/201?` should not match with {:?}",
+            n
+        );
+    }
+}