Remove more unnecessary libc usage (#1229)

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

tests/asm.arm/Cargo.toml

@@ -1,5 +1,5 @@
 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.arm/src/test_asm.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.x86_64/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.x86_64/src/test_asm.rs

@@ -3,7 +3,7 @@
 use crate::atomics::{rust_atomics_entry, rust_new_atomics};
 use crate::math::{rust_ffs, rust_ffsl, rust_ffsll, rust_isfinite, rust_isinf_sign, rust_isnan};
 use crate::mem_x_fns::{rust_assume_aligned, rust_mem_x};
-use libc::{c_char, c_double, c_int, c_long, c_longlong, c_uint};
+use std::ffi::{c_char, c_double, c_int, c_long, c_longlong, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/builtins/src/test_builtins.rs

@@ -1,7 +1,7 @@
 use crate::cast_funptr::{rust_entry, rust_get_identity, rust_identity};
 use crate::casts::rust_cast_stuff;
 
-use libc::{c_int, c_uint, c_void};
+use std::ffi::{c_int, c_uint, c_void};
 
 use std::mem::transmute;
 
@@ -46,9 +46,9 @@ pub fn test_identity() {
         assert_eq!(rust_id, i);
     }
 
-    let transmuted_rust_identity: unsafe extern "C" fn(_: libc::c_int) -> libc::c_int =
+    let transmuted_rust_identity: unsafe extern "C" fn(_: c_int) -> c_int =
         unsafe { transmute(rust_get_identity()) };
-    let transmuted_identity: unsafe extern "C" fn(_: libc::c_int) -> libc::c_int =
+    let transmuted_identity: unsafe extern "C" fn(_: c_int) -> c_int =
         unsafe { transmute(get_identity()) };
 
     for i in 0..10 {

tests/casts/src/test_casts.rs

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

tests/conditionals/Cargo.toml

@@ -5,7 +5,7 @@ use crate::unused_conditionals::{
     rust_unused_conditional1, rust_unused_conditional2, rust_unused_conditional3,
 };
 use crate::else_if_chain::rust_entry4;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {
@@ -85,4 +85,4 @@ pub fn test_else_if_chain(){
         assert_eq!(entry4(20) , rust_entry4(20));
         assert_eq!(entry4(30) , rust_entry4(30));
     }
-}
+}

tests/conditionals/src/test_conditionals.rs

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

tests/enums/Cargo.toml

@@ -9,7 +9,7 @@ use crate::non_canonical_enum_def::{
 use crate::top_enum::{rust_entry4, E as otherE};
 use crate::enum_compound::rust_entry6;
 
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/enums/src/test_enums.rs

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

tests/example/Cargo.toml

@@ -1,5 +1,5 @@
 use crate::add::rust_add;
-use libc::c_uint;
+use std::ffi::c_uint;
 
 #[link(name = "test")]
 extern "C" {

tests/example/src/test_add.rs

@@ -1,5 +1,5 @@
 use crate::sub::rust_sub;
-use libc::c_uint;
+use std::ffi::c_uint;
 
 #[link(name = "test")]
 extern "C" {

tests/example/src/test_sub.rs

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

tests/floats/Cargo.toml

@@ -1,5 +1,5 @@
 use crate::no_float_wrapping_neg::{rust_double_inc_dec, rust_float_inc_dec, rust_no_wrapping_neg};
-use libc::{c_double, c_float};
+use std::ffi::{c_double, c_float};
 
 #[link(name = "test")]
 extern "C" {

tests/floats/src/test_no_wrapping_neg.rs

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

tests/gotos/Cargo.toml

@@ -1,5 +1,5 @@
 use crate::irreducible::rust_irreducible;
-use libc::c_int;
+use std::ffi::c_int;
 
 #[link(name = "test")]
 extern "C" {

tests/gotos/src/test_irreducible.rs

@@ -1,6 +1,6 @@
 use crate::stmt_expr::rust_stmt_expr_func;
 
-use libc::c_int;
+use std::ffi::c_int;
 
 pub fn test_stmt_expr_relooper() {
     unsafe {

tests/gotos/src/test_stmt_expr.rs

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

tests/ints/Cargo.toml

@@ -1,18 +1,18 @@
 
 // `const`-ness of variable bindings (both in function arguments and locals) in C corresponds
 // directly to `mut`-ness of pattern bindings in Rust.
-int constant_arguments(int const x /* should be 'x: libc::c_int' */) {
-    int const y = x + 2;           // should be 'y: libc::c_int'
+int constant_arguments(int const x /* should be 'x: std::ffi::c_int' */) {
+    int const y = x + 2;           // should be 'y: std::ffi::c_int'
     return y;
 }
 
 // Still just a `const` argument - nothing special here
-void constant_pointer(int *const x /* should be 'x: *mut libc::c_int' */) {
+void constant_pointer(int *const x /* should be 'x: *mut std::ffi::c_int' */) {
     *x += 1;
 }
 
 // `const`-ness of pointee type in C corresponds directly to `const`/`mut` pointers in Rust
-int pointer_to_constant(int const *x /* should be 'mut x: *const libc::c_int' */) {
+int pointer_to_constant(int const *x /* should be 'mut x: *const std::ffi::c_int' */) {
     return x[1] + 1;
 }
 

tests/ints/src/const_test.c

@@ -13,8 +13,8 @@ int identity(x)
 void implicit_int(void)
 {
     // assign to t using the address-of operator
-    my_fn *t = &identity;                    // 't: my_fn: fn(libc::c_int) -> libc::c_int'
+    my_fn *t = &identity;                    // 't: my_fn: fn(std::ffi::c_int) -> std::ffi::c_int'
     // assign to u using function to pointer decay
-    my_fn *u = identity;                    // 't: my_fn: fn(libc::c_int) -> libc::c_int'
+    my_fn *u = identity;                    // 't: my_fn: fn(std::ffi::c_int) -> std::ffi::c_int'
 }
 

tests/ints/src/implicit_int.c

@@ -1,5 +1,5 @@
 use crate::arithmetic::rust_entry2;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_arithmetic.rs

@@ -1,6 +1,6 @@
 use crate::compound_assignment::rust_compound_assignment;
 
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_compound_assignment.rs

@@ -1,5 +1,5 @@
 use crate::const_test::rust_entry4;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_const.rs

@@ -2,7 +2,7 @@
 
 
 use crate::implicit_int::{identity as rust_identity, implicit_int as rust_implicit_int};
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 extern "C" {
     fn identity(_: c_int) -> c_int;

tests/ints/src/test_implicit_ints.rs

@@ -1,6 +1,6 @@
 use crate::chars::rust_multibyte_chars;
 use crate::size_t::rust_entry;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_ints.rs

@@ -1,5 +1,5 @@
 use crate::sieve_of_eratosthenes::rust_sieve_of_eratosthenes;
-use libc::c_int;
+use std::ffi::c_int;
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_sieve_of_eratosthenes.rs

@@ -1,5 +1,5 @@
 use crate::volatile::rust_entry3;
-use libc::{c_int, c_uint};
+use std::ffi::{c_int, c_uint};
 
 #[link(name = "test")]
 extern "C" {

tests/ints/src/test_volatile.rs

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

tests/items/Cargo.toml

@@ -1,5 +1,5 @@
 use crate::linking::{rust_l, rust_w};
-use libc::c_int;
+use std::ffi::c_int;
 
 #[link(name = "test")]
 extern "C" {