Remove more unnecessary libc usage (immunant#1229)

By using `std::ffi` types. A follow-up to immunant#1221 and immunant#1222.

Author: kkysen

Cargo.lock

@@ -14,8 +14,5 @@ categories.workspace = true
 [dependencies]
 c2rust-bitfields-derive = { version = "0.20.0", path = "../c2rust-bitfields-derive" }
 
-[dev-dependencies]
-libc = "0.2"
-
 [features]
 no_std = []

c2rust-bitfields/Cargo.toml

@@ -43,9 +43,9 @@ And this is enough to build our rust struct:
 #[repr(C, align(1))]
 #[derive(BitfieldStruct)]
 struct Date {
-    #[bitfield(name = "day", ty = "libc::c_uchar", bits = "0..=4")]
-    #[bitfield(name = "month", ty = "libc::c_uchar", bits = "5..=8")]
-    #[bitfield(name = "year", ty = "libc::c_ushort", bits = "9..=23")]
+    #[bitfield(name = "day", ty = "std::ffi::c_uchar", bits = "0..=4")]
+    #[bitfield(name = "month", ty = "std::ffi::c_uchar", bits = "5..=8")]
+    #[bitfield(name = "year", ty = "std::ffi::c_ushort", bits = "9..=23")]
     day_month_year: [u8; 3]
 }
 

c2rust-bitfields/README.md

@@ -1,5 +1,5 @@
 use c2rust_bitfields::BitfieldStruct;
-use libc::{c_double, c_short, c_uchar, c_uint, c_ulong, c_ushort};
+use std::ffi::{c_double, c_short, c_uchar, c_uint, c_ulong, c_ushort};
 use std::mem::{size_of, transmute};
 
 #[link(name = "test")]
@@ -46,8 +46,8 @@ struct CompactDate {
     // Compact combination of d + m
     // which can't be accessed via ptr in C anyway
     // so we combine the fields into one:
-    #[bitfield(name = "d", ty = "libc::c_uchar", bits = "0..=4")]
-    #[bitfield(name = "m", ty = "libc::c_uchar", bits = "8..=11")]
+    #[bitfield(name = "d", ty = "std::ffi::c_uchar", bits = "0..=4")]
+    #[bitfield(name = "m", ty = "std::ffi::c_uchar", bits = "8..=11")]
     d_m: [u8; 2],
     y: u16,
 }
@@ -190,8 +190,8 @@ fn test_overflow() {
 struct OverlappingByteDate {
     // This is also compact, however, the first byte is shared between the two
     // bitfields and the month also has a bit in the second byte
-    #[bitfield(name = "d", ty = "libc::c_ulong", bits = "0..=4")]
-    #[bitfield(name = "m", ty = "libc::c_ushort", bits = "5..=8")]
+    #[bitfield(name = "d", ty = "std::ffi::c_ulong", bits = "0..=4")]
+    #[bitfield(name = "m", ty = "std::ffi::c_ushort", bits = "5..=8")]
     d_m: [u8; 2],
     y: u16,
     #[bitfield(padding)]
@@ -261,11 +261,11 @@ fn test_overlapping_byte_date2() {
 #[derive(BitfieldStruct, Copy, Clone)]
 struct UnnamedBitfield {
     z: f64,
-    #[bitfield(name = "x", ty = "libc::c_ushort", bits = "0..=4")]
+    #[bitfield(name = "x", ty = "std::ffi::c_ushort", bits = "0..=4")]
     x: [u8; 1],
     #[bitfield(padding)]
     _pad: [u8; 1],
-    #[bitfield(name = "y", ty = "libc::c_ushort", bits = "0..=8")]
+    #[bitfield(name = "y", ty = "std::ffi::c_ushort", bits = "0..=8")]
     y: [u8; 2],
 }
 
@@ -301,9 +301,9 @@ fn test_unnamed_bitfield() {
 #[repr(C, align(2))]
 #[derive(BitfieldStruct, Copy, Clone)]
 struct SignedBitfields {
-    #[bitfield(name = "x", ty = "libc::c_short", bits = "0..=3")]
-    #[bitfield(name = "y", ty = "libc::c_ushort", bits = "4..=8")]
-    #[bitfield(name = "z", ty = "libc::c_short", bits = "9..=13")]
+    #[bitfield(name = "x", ty = "std::ffi::c_short", bits = "0..=3")]
+    #[bitfield(name = "y", ty = "std::ffi::c_ushort", bits = "4..=8")]
+    #[bitfield(name = "z", ty = "std::ffi::c_short", bits = "9..=13")]
     x_y_z: [u8; 2],
 }
 
@@ -478,8 +478,8 @@ fn test_signed_underflow_overflow() {
 #[repr(C, align(2))]
 #[derive(BitfieldStruct, Copy, Clone)]
 struct SingleBits {
-    #[bitfield(name = "x", ty = "libc::c_ushort", bits = "0..=0")]
-    #[bitfield(name = "y", ty = "libc::c_short", bits = "1..=1")]
+    #[bitfield(name = "x", ty = "std::ffi::c_ushort", bits = "0..=0")]
+    #[bitfield(name = "y", ty = "std::ffi::c_short", bits = "1..=1")]
     x_y: [u8; 1],
     #[bitfield(padding)]
     _pad: [u8; 1],
@@ -532,9 +532,9 @@ fn test_single_bits() {
 #[repr(C, align(1))]
 #[derive(BitfieldStruct)]
 struct ThreeByteDate {
-    #[bitfield(name = "day", ty = "libc::c_uchar", bits = "0..=4")]
-    #[bitfield(name = "month", ty = "libc::c_uchar", bits = "5..=8")]
-    #[bitfield(name = "year", ty = "libc::c_ushort", bits = "9..=23")]
+    #[bitfield(name = "day", ty = "std::ffi::c_uchar", bits = "0..=4")]
+    #[bitfield(name = "month", ty = "std::ffi::c_uchar", bits = "5..=8")]
+    #[bitfield(name = "year", ty = "std::ffi::c_ushort", bits = "9..=23")]
     day_month_year: [u8; 3],
 }
 

c2rust-bitfields/c2rust-tests/test_structs.rs

@@ -13,7 +13,7 @@ Then create a new `.rs` file with the following skeleton (_does not need to be a
 ```rust
 use crate::c_file::rust_example;
 
-use libc::c_int;
+use std::ffi::c_int;
 
 #[link(name = "test")]
 extern "C" {

tests/README.md

@@ -4,4 +4,3 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-libc = "0.2"

tests/arrays/Cargo.toml

@@ -1,7 +1,7 @@
 use crate::arrays::rust_entry;
 use crate::incomplete_arrays::{rust_check_some_ints, rust_entry2, rust_test_sized_array};
 use crate::variable_arrays::{rust_alloca_arrays, rust_variable_arrays};
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/arrays/src/test_arrays.rs

@@ -4,5 +4,4 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-libc = "0.2"
 c2rust-asm-casts = { path = "../../c2rust-asm-casts", version = "0.20.0" }

tests/asm.aarch64/Cargo.toml

@@ -1,7 +1,7 @@
 //! extern_crate_c2rust_asm_casts
 
 use crate::asm::rust_entry;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/asm.aarch64/src/test_asm.rs

@@ -4,4 +4,3 @@ version = "0.1.0"
 edition = "2021"
 
 [dependencies]
-libc = "0.2"