capstone-rs: Remove runtime depdendency on libc

* C types under `core::ffi` have been stable since 1.64.0
* `core::ffi::CStr` was already in use, so we can use it instead
  of `libc::strlen`.

Since libcore has everything we need, remove the dependency on the libc
crate at runtime.

Author: XrXr

Cargo.lock

@@ -17,7 +17,6 @@ travis-ci = { repository = "capstone-rust/capstone-rs" }
 
 [dependencies]
 capstone-sys = { path = "../capstone-sys", version = "0.17.0",  default-features = false }
-libc = { version = "0.2", default-features = false }
 static_assertions = "1.1.0"
 
 [dev-dependencies]

capstone-rs/Cargo.toml

@@ -2,10 +2,10 @@
 
 use core::convert::{From, TryInto};
 use core::{cmp, fmt, slice};
+use core::ffi::c_uint;
 
 use capstone_sys::{
     arm_op_mem, arm_op_type, arm_shifter, cs_ac_type, cs_arm, cs_arm_op, cs_arm_op__bindgen_ty_2};
-use libc::c_uint;
 
 pub use crate::arch::arch_builder::arm::*;
 use crate::arch::DetailsArchInsn;
@@ -301,7 +301,7 @@ mod test {
     fn test_armshift() {
         use super::arm_shifter::*;
         use super::ArmShift::*;
-        use libc::c_uint;
+        use core::ffi::c_uint;
 
         fn t(shift_type_value: (arm_shifter, c_uint), arm_shift: ArmShift) {
             let (shift_type, value) = shift_type_value;

capstone-rs/src/arch/arm.rs

@@ -1,13 +1,12 @@
 //! Contains arm64-specific types
 
-use libc::c_uint;
-
 pub use crate::arch::arch_builder::arm64::*;
 use crate::arch::DetailsArchInsn;
 use crate::instruction::{AccessType, RegId, RegIdInt};
 use capstone_sys::{arm64_op_mem, arm64_op_sme_index, arm64_op_type, cs_ac_type, cs_arm64, cs_arm64_op};
 use core::convert::{From, TryInto};
 use core::{cmp, fmt, mem, slice};
+use core::ffi::c_uint;
 
 // Re-exports
 pub use capstone_sys::arm64_barrier_op as ArmBarrierOp;
@@ -306,7 +305,7 @@ mod test {
     fn test_arm64shift() {
         use super::arm64_shifter::*;
         use super::Arm64Shift::*;
-        use libc::c_uint;
+        use core::ffi::c_uint;
 
         fn t(shift_type_value: (arm64_shifter, c_uint), arm64_shift: Arm64Shift) {
             let (shift_type, value) = shift_type_value;

capstone-rs/src/arch/arm64.rs

@@ -2,8 +2,8 @@
 
 use core::convert::From;
 use core::{cmp, fmt, slice};
+use core::ffi::c_int;
 
-use libc::c_int;
 use capstone_sys::{
     cs_tms320c64x, cs_tms320c64x_op, tms320c64x_funit, tms320c64x_mem_dir, tms320c64x_mem_disp,
     tms320c64x_mem_mod, tms320c64x_op_mem, tms320c64x_op_type,
@@ -256,7 +256,7 @@ def_arch_details_struct!(
 mod test {
     use super::*;
     use capstone_sys::*;
-    use libc::{c_int, c_uint};
+    use core::ffi::{c_int, c_uint};
 
     const OP_MEM_ZERO: tms320c64x_op_mem = tms320c64x_op_mem {
         base: 0,

capstone-rs/src/arch/tms320c64x.rs

@@ -1,14 +1,12 @@
 use alloc::boxed::Box;
 use alloc::string::String;
 use core::convert::From;
-use core::ffi::CStr;
+use core::ffi::{c_int, c_uint, c_void, CStr};
 use core::marker::PhantomData;
 use core::mem::MaybeUninit;
 #[cfg(feature = "std")]
 use std::ffi::CString;
 
-use libc::{c_int, c_void};
-
 use capstone_sys::cs_opt_value::*;
 use capstone_sys::*;
 
@@ -17,7 +15,7 @@ use crate::constants::{Arch, Endian, ExtraMode, Mode, OptValue, Syntax};
 use crate::instruction::{Insn, InsnDetail, InsnGroupId, InsnId, Instructions, RegId};
 use crate::{error::*, PartialInitRegsAccess};
 
-use {crate::ffi::str_from_cstr_ptr, alloc::string::ToString, libc::c_uint};
+use {crate::ffi::str_from_cstr_ptr, alloc::string::ToString};
 
 /// Length of `cs_regs`
 pub(crate) const REGS_ACCESS_BUF_LEN: usize = 64;

capstone-rs/src/capstone.rs

@@ -1,7 +1,7 @@
 //! Functions useful for FFI
 
-use core::{slice, str};
-use libc::{self, c_char};
+use core::ffi::c_char;
+use core::ffi::CStr;
 
 // This function will go unused in Diet mode
 #[allow(unused)]
@@ -17,11 +17,10 @@ pub(crate) unsafe fn str_from_cstr_ptr<'a>(ptr: *const c_char) -> Option<&'a str
     if ptr.is_null() {
         return None;
     }
-    let len = libc::strlen(ptr);
     /* ASSUMPTION: capstone returns NUL terminated string */
-    let view: &[u8] = slice::from_raw_parts(ptr as *const u8, len as usize);
+    let cstr = CStr::from_ptr(ptr);
     /* ASSUMPTION: capstone returns a valid UTF-8 string */
-    Some(str::from_utf8_unchecked(view))
+    Some(core::str::from_utf8_unchecked(cstr.to_bytes()))
 }
 
 #[cfg(test)]

capstone-rs/src/ffi.rs

@@ -5,14 +5,14 @@
     clippy::upper_case_acronyms
 )]
 
+use core::ffi::c_uint;
 use core::{convert::TryInto, fmt::Debug, mem::MaybeUninit};
 
 use alloc::vec::Vec;
 #[cfg(feature = "full")]
 use {alloc::string::String, std::collections::HashSet};
 
 use capstone_sys::cs_group_type;
-use libc::c_uint;
 use pretty_assertions::assert_eq;
 
 use super::arch::*;