use xdg-mime by default on linux, infer elsewhere

Cargo.lock

@@ -179,6 +179,7 @@ name = "fif"
 version = "0.2.4"
 dependencies = [
  "cached",
+ "cfg-if",
  "clap",
  "env_logger",
  "exitcode",

Cargo.toml

@@ -15,10 +15,10 @@ exclude = [".idea/", "Cross.toml", "*.sh"]
 #license-file = "LICENSE"
 
 [features]
-default = ["multi-threaded", "infer-backend"]
+default = ["multi-threaded"]
 multi-threaded = ["rayon"]
-infer-backend = ["infer"]
+infer-backend = []
-xdg-mime-backend = ["xdg-mime"]
+xdg-mime-backend = []
 
 [dependencies]
 walkdir = "2.3.1"
@@ -27,13 +27,14 @@ smartstring = "0.2.6"
 mime_guess = "2.0.3"
 snailquote = "0.3.0"
 once_cell = "1.5.2"
+infer = { version = "0.3.4" }
 rayon = { version = "1.5.0", optional = true }
-infer = { version = "0.3.4", optional = true }
 exitcode = "1.1.2"
+cfg-if = "1.0.0"
 
 # use git version while waiting on a release incorporating https://github.com/ebassi/xdg-mime-rs/commit/de5a6dd
 [target.'cfg(not(target_os = "windows"))'.dependencies]
-xdg-mime = {git = "https://github.com/ebassi/xdg-mime-rs", version = "0.3", rev = "de5a6dd", optional = true }
+xdg-mime = {git = "https://github.com/ebassi/xdg-mime-rs", version = "0.3", rev = "de5a6dd" }
 
 [dependencies.clap]
 version = "3.0.0-beta.2"

src/inspectors.rs

@@ -10,8 +10,6 @@ use smartstring::alias::String;
 
 use crate::mimedb::MimeDb;
 
-// use log::{debug, warn};
-
 // rather than reading once into a large buffer, it tends to be faster to first try identifying the file from a small
 // chunk read from the top, and *then* proceeding with the large buffer. many file formats can be easily identified by
 // the first 128 bytes. of course, not all formats can, and some (OOXML...) require reading a long ways in.
@@ -87,6 +85,11 @@ cached! {
 				} else if mime == Mime::from_str("application/msword").unwrap() {
 					// classic office files considered harmful
 					vec![String::from("doc"), String::from("xls"), String::from("ppt")]
+
+				} else if mime == Mime::from_str("application/zip").unwrap() {
+					// neither xdg-mime nor infer seem to be able to detect office XML files properly...
+					[vec![String::from("zip"), String::from("docx"), String::from("xlsx"), String::from("pptx")], possible_exts].concat()
+
 				} else {
 					possible_exts
 				})

src/main.rs

@@ -40,10 +40,10 @@ mod mimedb;
 mod parameters;
 mod scanerror;
 
-#[cfg(feature = "infer-backend")]
+#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 static MIMEDB: OnceCell<mimedb::InferDb> = OnceCell::new();
 
-#[cfg(feature = "xdg-mime-backend")]
+#[cfg(any(all(target_os = "linux", not(feature = "infer-backend")), all(not(target_os = "linux"), not(feature = "xdg-mime-backend"))))]
 static MIMEDB: OnceCell<mimedb::XdgDb> = OnceCell::new();
 
 // TODO: test if this actually works on a windows machine
@@ -162,13 +162,13 @@ fn main() {
 		// .target(env_logger::Target::Stdout) // log to stdout rather than stderr
 		.init();
 
-	#[cfg(feature = "infer-backend")]
+	#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 		MIMEDB
 		.set(mimedb::InferDb::init())
 		.or(Err("Failed to initialise Infer backend!"))
 		.unwrap();
 
-	#[cfg(feature = "xdg-mime-backend")]
+	#[cfg(any(all(target_os = "linux", not(feature = "infer-backend")), all(not(target_os = "linux"), not(feature = "xdg-mime-backend"))))]
 	MIMEDB
 		.set(mimedb::XdgDb::init())
 		.or(Err("Failed to initialise XDG Mime backend!"))

src/mimedb.rs

@@ -1,4 +1,4 @@
-#[cfg(feature = "infer-backend")]
+#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 use std::str::FromStr;
 
 use mime_guess::Mime;
@@ -8,11 +8,12 @@ pub trait MimeDb {
 	fn get_type(&self, data: &[u8]) -> Option<Mime>;
 }
 
-#[cfg(feature = "infer-backend")]
+#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 pub struct InferDb {
 	db: infer::Infer,
 }
 
+#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 fn open_document_check(buf: &[u8], kind: &str) -> bool {
 	let mime = format!("application/vnd.oasis.opendocument.{}", kind);
 	let mime = mime.as_bytes();
@@ -20,7 +21,7 @@ fn open_document_check(buf: &[u8], kind: &str) -> bool {
 	buf.len() > 38 + mime.len() && buf.starts_with(b"PK\x03\x04") && buf[38..mime.len() + 38] == mime[..]
 }
 
-#[cfg(feature = "infer-backend")]
+#[cfg(any(all(not(target_os = "linux"), not(feature = "xdg-mime-backend")), all(target_os = "linux", feature = "infer-backend")))]
 impl MimeDb for InferDb {
 	fn init() -> Self {
 		let mut info = infer::Infer::new();
@@ -82,12 +83,12 @@ impl MimeDb for InferDb {
 	}
 }
 
-#[cfg(feature = "xdg-mime-backend")]
+#[cfg(any(all(target_os = "linux", not(feature = "infer-backend")), all(not(target_os = "linux"), not(feature = "xdg-mime-backend"))))]
 pub struct XdgDb {
 	db: xdg_mime::SharedMimeInfo,
 }
 
-#[cfg(feature = "xdg-mime-backend")]
+#[cfg(any(all(target_os = "linux", not(feature = "infer-backend")), all(not(target_os = "linux"), not(feature = "xdg-mime-backend"))))]
 impl MimeDb for XdgDb {
 	fn init() -> Self {
 		Self {