rustix/windows-sys for page size; drop maplit (#7876)

The `page_size` crate is a simple libc wrapper for Unix and uses
`winapi-rs` for Windows. `windows-sys` and `windows-rs` are the modern
alternatives for the unmaintained `winapi-rs`. Both crates are
maintained by Microsoft - they're official. Getting the page size is a
simple call for both Unix and Windows.

Besides Unix and Windows, I also added the page size for wasm32 which
the `page_size` crate did not support. `wasm32`'s page size is a
constant that is defined by the spec, so I hard coded it without adding
additional dependencies.

Finally, I dropped `maplit` which is seven years old and only used in
one place. Calling `collect()` with a single item iterator is idiomatic
as well as better in this case because Rust can optimize it. `maplit`
called `HashMap::insert` which over allocates to amortize future allocs.

Cargo.lock

@@ -2141,12 +2141,6 @@ dependencies = [
  "quote",
 ]
 
-[[package]]
-name = "maplit"
-version = "1.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3e2e65a1a2e43cfcb47a895c4c8b10d1f4a61097f9f254f183aee60cad9c651d"
-
 [[package]]
 name = "md-5"
 version = "0.10.6"
@@ -3331,7 +3325,6 @@ name = "rustpython-derive-impl"
 version = "0.5.0"
 dependencies = [
  "itertools 0.14.0",
- "maplit",
  "proc-macro2",
  "quote",
  "rustpython-compiler-core",
@@ -3541,7 +3534,6 @@ dependencies = [
  "openssl",
  "openssl-probe",
  "openssl-sys",
- "page_size",
  "parking_lot",
  "paste",
  "pbkdf2",

Cargo.toml

@@ -233,7 +233,6 @@ mac_address = "1.1.3"
 malachite-bigint = "0.9.1"
 malachite-q = "0.9.1"
 malachite-base = "0.9.1"
-maplit = "1.0.2"
 md-5 = "0.10.1"
 memchr = "2.8.0"
 memmap2 = "0.9.10"
@@ -248,7 +247,6 @@ openssl = "0.10.79"
 openssl-sys = "0.9.110"
 openssl-probe = "0.2.1"
 optional = "0.5"
-page_size = "0.6"
 parking_lot = "0.12.3"
 paste = "1.0.15"
 pbkdf2 = "0.12"
@@ -263,7 +261,7 @@ radium = "1.1.1"
 rand = "0.9"
 rand_core = { version = "0.9", features = ["os_rng"] }
 result-like = "0.5.0"
-rustix = { version = "1.1", features = ["event", "system"] }
+rustix = { version = "1.1", features = ["event", "param", "system"] }
 rustls = { version = "0.23.39", default-features = false }
 rustls-native-certs = "0.8"
 rustls-pemfile = "2.2"

crates/derive-impl/Cargo.toml

@@ -16,7 +16,6 @@ rustpython-doc = { workspace = true }
 itertools = { workspace = true }
 syn = { workspace = true, features = ["full", "extra-traits"] }
 
-maplit = { workspace = true }
 proc-macro2 = { workspace = true }
 quote = { workspace = true }
 syn-ext = { workspace = true, features = ["full"] }

crates/derive-impl/src/compile_bytecode.rs

@@ -83,12 +83,14 @@ impl CompilationSource {
             CompilationSourceKind::Dir { base, rel_path } => {
                 self.compile_dir(base, &base.join(rel_path), "", mode, compiler)
             }
-            _ => Ok(hashmap! {
-                module_name.to_string() => CompiledModule {
+            _ => Ok(core::iter::once((
+                module_name.to_string(),
+                CompiledModule {
                     code: self.compile_single(mode, module_name, compiler)?,
                     package: false,
                 },
-            }),
+            ))
+            .collect()),
         }
     }
 

crates/derive-impl/src/lib.rs

@@ -4,9 +4,6 @@
 
 extern crate proc_macro;
 
-#[macro_use]
-extern crate maplit;
-
 #[macro_use]
 mod error;
 #[macro_use]

crates/host_env/Cargo.toml

@@ -19,10 +19,8 @@ paste = { workspace = true }
 
 [target.'cfg(unix)'.dependencies]
 nix = { workspace = true }
-uname = "0.1.1"
-
-[target.'cfg(any(target_os = "linux", target_os = "android", target_os = "redox"))'.dependencies]
 rustix = { workspace = true }
+uname = "0.1.1"
 
 [target.'cfg(any(not(target_arch = "wasm32"), target_os = "wasi"))'.dependencies]
 num_cpus = "1.17.0"

crates/host_env/src/os.rs

@@ -25,6 +25,7 @@ use {
         Storage::FileSystem::{
             FILE_FLAG_BACKUP_SEMANTICS, INVALID_SET_FILE_POINTER, SetFilePointer, SetFileTime,
         },
+        System::SystemInformation::{GetSystemInfo, SYSTEM_INFO},
     },
 };
 
@@ -132,6 +133,48 @@ pub fn cpu_count() -> usize {
     1
 }
 
+#[cfg(unix)]
+pub fn page_size() -> usize {
+    rustix::param::page_size()
+}
+
+#[cfg(target_arch = "wasm32")]
+pub const fn page_size() -> usize {
+    // WebAssembly's page size is a constant defined by the spec.
+    1024 * 64
+}
+
+#[cfg(windows)]
+pub fn page_size() -> usize {
+    let mut info = SYSTEM_INFO::default();
+    unsafe {
+        GetSystemInfo(&mut info);
+    }
+    info.dwPageSize as _
+}
+
+#[cfg(unix)]
+pub fn alloc_granularity() -> usize {
+    // On Unix-likes, the page size is the smallest allocation unit rather than a separate concept
+    // of allocation granularity.
+    page_size()
+}
+
+#[cfg(target_arch = "wasm32")]
+pub const fn alloc_granularity() -> usize {
+    // Like Unix, WebAssembly doesn't separate page size and alloc granularity.
+    page_size()
+}
+
+#[cfg(windows)]
+pub fn alloc_granularity() -> usize {
+    let mut info = SYSTEM_INFO::default();
+    unsafe {
+        GetSystemInfo(&mut info);
+    }
+    info.dwAllocationGranularity as _
+}
+
 pub fn device_encoding(_fd: i32) -> Option<String> {
     #[cfg(any(
         target_os = "android",

crates/stdlib/Cargo.toml

@@ -102,7 +102,6 @@ uuid = { workspace = true, features = ["v1"] }
 
 # mmap + socket dependencies
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
-page_size = { workspace = true }
 gethostname = { workspace = true }
 socket2 = { workspace = true, features = ["all"] }
 dns-lookup = { workspace = true }

crates/stdlib/src/mmap.rs

@@ -131,16 +131,15 @@ mod mmap {
     #[pyattr]
     const ACCESS_COPY: u32 = AccessMode::Copy as u32;
 
-    #[cfg(not(target_arch = "wasm32"))]
     #[pyattr(name = "PAGESIZE", once)]
     fn page_size(_vm: &VirtualMachine) -> usize {
-        page_size::get()
+        rustpython_host_env::os::page_size()
     }
 
     #[cfg(not(target_arch = "wasm32"))]
     #[pyattr(name = "ALLOCATIONGRANULARITY", once)]
     fn granularity(_vm: &VirtualMachine) -> usize {
-        page_size::get_granularity()
+        rustpython_host_env::os::alloc_granularity()
     }
 
     #[pyattr(name = "error", once)]