update README

Cargo.lock

@@ -168,6 +168,12 @@ dependencies = [
  "litrs",
 ]
 
+[[package]]
+name = "equivalent"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "877a4ace8713b0bcf2a4e7eec82529c029f1d0619886d18145fea96c3ffe5c0f"
+
 [[package]]
 name = "errno"
 version = "0.3.14"
@@ -178,12 +184,28 @@ dependencies = [
  "windows-sys 0.60.2",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.16.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5419bdc4f6a9207fbeba6d11b604d481addf78ecd10c11ad51e76c2f6482748d"
+
 [[package]]
 name = "heck"
 version = "0.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2304e00983f87ffb38b55b444b5e3b60a884b5d30c0fca7d82fe33449bbe55ea"
 
+[[package]]
+name = "indexmap"
+version = "2.11.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4b0f83760fb341a774ed326568e19f5a863af4a952def8c39f9ab92fd95b88e5"
+dependencies = [
+ "equivalent",
+ "hashbrown",
+]
+
 [[package]]
 name = "is_terminal_polyfill"
 version = "1.70.1"
@@ -495,6 +517,7 @@ dependencies = [
 name = "wfassoc"
 version = "0.1.0"
 dependencies = [
+ "indexmap",
  "regex",
  "thiserror",
  "uuid",

README.md

@@ -6,6 +6,23 @@
 
 ## Introduction
 
-* wfassoc: Core Rust library. Rust programmer can directly utilize it.
-* wfassoc_dylib: A dynamic library exposed for C/C++ and other languages users.
-* wfassoc_exec: A executable configuring file assocation according to user given profile and request.
+* `wfassoc`: Core Rust library. Rust programmer can directly utilize it.
+* `wfassoc_dylib`: A dynamic library exposed for C/C++ and other languages users.
+* `wfassoc_exec`: A executable configuring file assocation according to user given profile and request.
+
+If you are a programmer who just want to silently set your file association for user, 
+`wfassoc_exec` would be your best choice.
+The only things you need to do is that write a TOML description file,
+and provide it and `wfassoc_exec` with your executable.
+By executing `wfassoc_exec` with this TOML file in your executable,
+you can simply achieve this goal and analyze its return value to check whether it success.
+
+However, if you are prefering taht let user decide which file associations should be created,
+even have an UI displaying all current file association related with this program (like 7-Zip File Manager does),
+you can choose `wfassoc_dylib` for your solution.
+`wfassoc_dylib` expose all essential functions for this task.
+And you can build it with your own program.
+
+At last, if all scenarios above can not cover your requirements,
+you can utilize `wfassoc` directly in Rust, change all essential code in your favor,
+and finally produce the application which onlt suit for yourself.

wfassoc/Cargo.toml

@@ -8,7 +8,8 @@ license = "SPDX:MIT"
 
 [dependencies]
 thiserror = { workspace = true }
-windows-sys = { version = "0.60.2", features = ["Win32_Security", "Win32_System_SystemServices"] }
+windows-sys = { version = "0.60.2", features = ["Win32_Security", "Win32_System_SystemServices", "Win32_UI_Shell"] }
 winreg = { version = "0.55.0", features = ["transactions"] }
+indexmap = "2.11.4"
 regex = "1.11.3"
 uuid = "1.18.1"

wfassoc/src/lib.rs

@@ -4,14 +4,18 @@
 #[cfg(not(target_os = "windows"))]
 compile_error!("Crate wfassoc is only supported on Windows.");
 
+use regex::Regex;
 use std::ffi::OsStr;
+use std::fmt::Display;
 use std::path::{Path, PathBuf};
+use std::str::FromStr;
+use std::sync::LazyLock;
 use thiserror::Error as TeError;
+use indexmap::{IndexMap, IndexSet};
 use winreg::RegKey;
 use winreg::enums::{
     HKEY_CLASSES_ROOT, HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE, KEY_READ, KEY_WRITE,
 };
-use winreg::transaction::Transaction;
 
 // region: Error Types
 
@@ -22,10 +26,14 @@ pub enum WfError {
     NoPrivilege,
     #[error("error occurs when manipulating with Registry: {0}")]
     BadRegOper(#[from] std::io::Error),
+
     #[error("given full path to application is invalid")]
     BadFullAppPath,
-    #[error("failed when casting path or OS string into string")]
+    #[error("failed when casting OS string into string")]
     BadOsStrCast,
+    
+    #[error("file extension {0} is already registered")]
+    DupExt(String),
 }
 
 /// The result type used in this crate.
@@ -33,74 +41,6 @@ pub type WfResult<T> = Result<T, WfError>;
 
 // endregion
 
-// region: Scope and View
-
-/// The scope where wfassoc will register and unregister application.
-#[derive(Debug, Copy, Clone)]
-pub enum Scope {
-    /// Scope for current user.
-    User,
-    /// Scope for all users under this computer.
-    System,
-}
-
-/// The error occurs when cast View into Scope.
-#[derive(Debug, TeError)]
-#[error("hybrid view can not be cast into any scope")]
-pub struct TryFromViewError {}
-
-impl TryFromViewError {
-    fn new() -> Self {
-        Self {}
-    }
-}
-
-impl TryFrom<View> for Scope {
-    type Error = TryFromViewError;
-
-    fn try_from(value: View) -> Result<Self, Self::Error> {
-        match value {
-            View::User => Ok(Self::User),
-            View::System => Ok(Self::System),
-            View::Hybrid => Err(TryFromViewError::new()),
-        }
-    }
-}
-
-impl Scope {
-    /// Check whether we have enough privilege when operating in current scope.
-    /// If we have, return true, otherwise false.
-    fn has_privilege(&self) -> bool {
-        // If we operate on System, and we do not has privilege,
-        // we think we do not have privilege, otherwise,
-        // there is no privilege required.
-        !matches!(self, Self::System if !has_privilege())
-    }
-}
-
-/// The view when wfassoc querying file extension association.
-#[derive(Debug, Copy, Clone)]
-pub enum View {
-    /// The view of current user.
-    User,
-    /// The view of system.
-    System,
-    /// Hybrid view of User and System.
-    /// It can be seen as that we use System first and then use User to override any existing items.
-    Hybrid,
-}
-
-impl From<Scope> for View {
-    fn from(value: Scope) -> Self {
-        match value {
-            Scope::User => Self::User,
-            Scope::System => Self::System,
-        }
-    }
-}
-
-// endregion
-
 // region: Utilities
 
 /// The println macro only works on Debug mode
@@ -173,6 +113,20 @@ fn has_privilege() -> bool {
     is_member != 0
 }
 
+/// Notify Windows that some file associations are changed, and should refresh them.
+/// This function must be called once you change any file associations.
+fn notify_assoc_changed() -> () {
+    use windows_sys::Win32::UI::Shell::{SHCNE_ASSOCCHANGED, SHCNF_IDLIST, SHChangeNotify};
+    unsafe {
+        SHChangeNotify(
+            SHCNE_ASSOCCHANGED as i32,
+            SHCNF_IDLIST,
+            Default::default(),
+            Default::default(),
+        )
+    }
+}
+
 /// Try casting given &Path into &str.
 fn path_to_str(path: &Path) -> WfResult<&str> {
     path.to_str().ok_or(WfError::BadOsStrCast)
@@ -185,29 +139,198 @@ fn osstr_to_str(osstr: &OsStr) -> WfResult<&str> {
 
 // endregion
 
-// region: Registrar
+// region: Types
 
-/// The core registrar for register and unregister application.
-pub struct Registrar {
-    /// The fully qualified path to the application.
-    full_path: PathBuf,
+/// The token for access registered items in Program.
+/// This is usually returned when you registering them.
+pub type Token = usize;
+
+/// The scope where wfassoc will register and unregister application.
+#[derive(Debug, Copy, Clone)]
+pub enum Scope {
+    /// Scope for current user.
+    User,
+    /// Scope for all users under this computer.
+    System,
 }
 
-impl Registrar {
-    /// Create a new registrar for following operations.
-    pub fn new(full_path: &Path) -> Self {
-        Self {
-            full_path: full_path.to_path_buf(),
+/// The error occurs when cast View into Scope.
+#[derive(Debug, TeError)]
+#[error("hybrid View can not be cast into Scope")]
+pub struct TryFromViewError {}
+
+impl TryFromViewError {
+    fn new() -> Self {
+        Self {}
+    }
+}
+
+impl TryFrom<View> for Scope {
+    type Error = TryFromViewError;
+
+    fn try_from(value: View) -> Result<Self, Self::Error> {
+        match value {
+            View::User => Ok(Self::User),
+            View::System => Ok(Self::System),
+            View::Hybrid => Err(TryFromViewError::new()),
         }
     }
 }
 
-impl Registrar {
+impl Scope {
+    /// Check whether we have enough privilege when operating in current scope.
+    /// If we have, return true, otherwise false.
+    fn has_privilege(&self) -> bool {
+        // If we operate on System, and we do not has privilege,
+        // we think we do not have privilege, otherwise,
+        // there is no privilege required.
+        !matches!(self, Self::System if !has_privilege())
+    }
+}
+
+/// The view when wfassoc querying file extension association.
+#[derive(Debug, Copy, Clone)]
+pub enum View {
+    /// The view of current user.
+    User,
+    /// The view of system.
+    System,
+    /// Hybrid view of User and System.
+    /// It can be seen as that we use System first and then use User to override any existing items.
+    Hybrid,
+}
+
+impl From<Scope> for View {
+    fn from(value: Scope) -> Self {
+        match value {
+            Scope::User => Self::User,
+            Scope::System => Self::System,
+        }
+    }
+}
+
+// endregion
+
+// region: File Extension
+
+/// The struct representing an file extension which must start with dot (`.`)
+/// and followed by at least one arbitrary characters.
+#[derive(Debug, Clone, PartialEq, Eq, PartialOrd, Ord, Hash)]
+pub struct Ext {
+    /// The body of file extension (excluding dot).
+    body: String,
+}
+
+impl Ext {
+    /// Create an new file extension.
+    pub fn new(raw: &str) -> Result<Self, ParseExtError> {
+        Self::from_str(raw)
+    }
+
+    /// Get the body part of file extension (excluding dot)
+    pub fn inner(&self) -> &str {
+        &self.body
+    }
+}
+
+/// The error occurs when try parsing string into FileExt.
+#[derive(Debug, TeError)]
+#[error("given file extension name \"{inner}\" is invalid")]
+pub struct ParseExtError {
+    inner: String
+}
+
+impl ParseExtError {
+    fn new(inner: &str) -> Self {
+        Self { inner: inner.to_string() }
+    }
+}
+
+impl Display for Ext {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        write!(f, ".{}", self.body)
+    }
+}
+
+impl FromStr for Ext {
+    type Err = ParseExtError;
+
+    fn from_str(s: &str) -> Result<Self, Self::Err> {
+        static RE: LazyLock<Regex> = LazyLock::new(|| Regex::new(r"^\.([^\.]+)$").unwrap());
+        match RE.captures(s) {
+            Some(v) => Ok(Self {
+                body: v[1].to_string(),
+            }),
+            None => Err(ParseExtError::new(s)),
+        }
+    }
+}
+
+// endregion
+
+// region: Program
+
+/// The struct representing a complete program for registration and unregistration.
+pub struct Program {
+    /// The fully qualified path to the application.
+    full_path: PathBuf,
+    /// Optional default icon resource for overriding.
+    ///
+    /// TODO: Use specialized IconRc struct instead.
+    default_icon: Option<String>,
+    /// Optional friendly app name for overriding.
+    ///
+    /// TODO: Use specialized StringRc for overriding.
+    friendly_app_name: Option<String>,
+
+    /// The collection holding all file extensions supported by this program.
+    exts: IndexSet<Ext>,
+}
+
+impl Program {
+    /// Create a new registrar for following operations.
+    ///
+    /// `full_path` is the fully qualified path to the application.
+    ///
+    /// `default_icon` is an optional icon resource replacing the default one
+    /// fetched from the first icon resource of your executable application.
+    ///
+    /// `friendly_app_name` also is an optional string or string resource replacing
+    /// the info fetched from executable application's version information.
+    pub fn new(
+        full_path: &Path,
+        default_icon: Option<&str>,
+        friendly_app_name: Option<&str>,
+    ) -> Self {
+        Self {
+            full_path: full_path.to_path_buf(),
+            default_icon: default_icon.map(|s| s.to_string()),
+            friendly_app_name: friendly_app_name.map(|s| s.to_string()),
+            exts: IndexSet::new(),
+        }
+    }
+
+    /// Add file extension supported by this program.
+    pub fn add_ext(&mut self, ext: &Ext) -> WfResult<()> {
+        if self.exts.insert(ext.clone()) {
+            Ok(())
+        } else {
+            Err(WfError::DupExt(ext.to_string()))
+        }
+    }
+}
+
+impl Program {
     const APP_PATHS: &str = "Software\\Microsoft\\Windows\\CurrentVersion\\App Paths";
     const APPLICATIONS: &str = "Software\\Classes\\Applications";
 
     /// Register this application.
     pub fn register(&self, scope: Scope) -> WfResult<()> {
+        // Check privilege
+        if !scope.has_privilege() {
+            return Err(WfError::NoPrivilege);
+        }
+
         // Fetch root key.
         let hk = RegKey::predef(match scope {
             Scope::User => HKEY_CURRENT_USER,
@@ -216,7 +339,7 @@ impl Registrar {
         // Fetch file name and start in path.
         let file_name = self.extract_file_name()?;
         let start_in = self.extract_start_in()?;
-        
+
         // Create App Paths subkey
         debug_println!("Adding App Paths subkey...");
         let subkey_parent = hk.open_subkey_with_flags(Self::APP_PATHS, KEY_READ)?;
@@ -230,13 +353,31 @@ impl Registrar {
         let subkey_parent = hk.open_subkey_with_flags(Self::APPLICATIONS, KEY_READ)?;
         let (subkey, _) = subkey_parent.create_subkey_with_flags(file_name, KEY_WRITE)?;
         // Write Applications values
-        subkey.set_value("FriendlyAppName", &"WoW!")?;
+        if let Some(default_icon) = &self.default_icon {
+            subkey.set_value("DefaultIcon", default_icon)?;
+        }
+        if let Some(friendly_app_name) = &self.friendly_app_name {
+            subkey.set_value("FriendlyAppName", friendly_app_name)?;
+        }
+        if !self.exts.is_empty() {
+            let (supported_types, _) = subkey.create_subkey_with_flags("SupportedTypes", KEY_WRITE)?;
+            for ext in &self.exts {
+                supported_types.set_value(ext.to_string(), &"")?;
+            }
+        }
 
+        // Okey
+        notify_assoc_changed();
         Ok(())
     }
 
     /// Unregister this application.
     pub fn unregister(&self, scope: Scope) -> WfResult<()> {
+        // Check privilege
+        if !scope.has_privilege() {
+            return Err(WfError::NoPrivilege);
+        }
+
         // Fetch root key and file name.
         let hk = RegKey::predef(match scope {
             Scope::User => HKEY_CURRENT_USER,
@@ -255,6 +396,7 @@ impl Registrar {
         subkey_parent.delete_subkey_all(file_name)?;
 
         // Okey
+        notify_assoc_changed();
         Ok(())
     }
 
@@ -288,11 +430,12 @@ impl Registrar {
     }
 }
 
-impl Registrar {
+impl Program {
     /// Extract the file name part from full path to application,
     /// which was used in Registry path component.
     fn extract_file_name(&self) -> WfResult<&OsStr> {
-        // Get the file name part and make sure it is not empty
+        // Get the file name part and make sure it is not empty.
+        // Empty checker is CRUCIAL!
         self.full_path
             .file_name()
             .and_then(|p| if p.is_empty() { None } else { Some(p) })
@@ -303,6 +446,7 @@ impl Registrar {
     /// which basically is the stem of full path.
     fn extract_start_in(&self) -> WfResult<&OsStr> {
         // Get parent part and make sure it is not empty
+        // Empty checker is CRUCIAL!
         self.full_path
             .parent()
             .map(|p| p.as_os_str())

wfassoc_exec/src/main.rs

@@ -2,7 +2,7 @@ use clap::{Parser, Subcommand};
 use comfy_table::Table;
 use std::process;
 use thiserror::Error as TeError;
-use wfassoc::{Error as WfError, FileExt, Scope, View};
+use wfassoc::{Error as WfError, Ext, Scope, View};
 
 // region: Basic Types
 
@@ -95,7 +95,7 @@ fn run_query(cli: Cli) -> Result<()> {
         ".kra", ".xcf", ".avif", ".qoi", ".apng", ".exr",
     ];
 
-    for ext in exts.iter().map(|e| FileExt::new(e).unwrap()) {
+    for ext in exts.iter().map(|e| Ext::new(e).unwrap()) {
         if let Some(ext_assoc) = ext.query(View::Hybrid) {
             println!("{:?}", ext_assoc)
         }