Add platform specific rule for strerror_r

Author: lucic71

rules/cstring/src.c

@@ -41,6 +41,14 @@ void *f24(const void *a0, int a1, size_t a2) { return memrchr(a0, a1, a2); }
 
 int f27(const char *a0, const char *a1) { return strcasecmp(a0, a1); }
 
+#if defined(__linux__)
 char *f28(int errnum, char *buf, size_t buflen) {
     return strerror_r(errnum, buf, buflen);
 }
+#elif defined(__APPLE__)
+int f28(int errnum, char *buf, size_t buflen) {
+    return strerror_r(errnum, buf, buflen);
+}
+#else
+#error "Unsupported platform for strerror_r"
+#endif

rules/cstring/tgt_unsafe.rs

@@ -138,7 +138,13 @@ unsafe fn f27(a0: *const u8, a1: *const u8) -> i32 {
 // (immutable) static string (in which case buf is unused)
 //
 // So it's not 100% correct to always return a1. But the Rust libc version only returns int.
+#[cfg(target_os = "linux")]
 unsafe fn f28(a0: i32, a1: *mut u8, a2: usize) -> *mut u8 {
     libc::strerror_r(a0, a1 as *mut i8, a2 as usize);
     a1
 }
+
+#[cfg(target_os = "macos")]
+unsafe fn f28(a0: i32, a1: *mut u8, a2: usize) -> i32 {
+    libc::strerror_r(a0, a1 as *mut i8, a2 as usize)
+}