verify monetary header includes

src/header/monetary/cbindgen.toml

@@ -1,5 +1,16 @@
-sys_includes = ["stddef.h", "stdint.h", "features.h"]
+# POSIX header spec: https://pubs.opengroup.org/onlinepubs/9799919799/basedefs/monetary.h.html
+#
+# Spec quotations relating to includes:
+# - "The <monetary.h> header shall define the locale_t type as described in <locale.h>."
+# - "The <monetary.h> header shall define the size_t type as described in <stddef.h>."
+# - "The <monetary.h> header shall define the ssize_t type as described in <sys/types.h>."
+#
+# sys/types.h brings in stddef.h
+sys_includes = ["sys/types.h"]
 include_guard = "_RELIBC_MONETARY_H"
+after_includes = """
+#include <bits/locale-t.h> // for locale_t from locale.h
+"""
 language = "C"
 style = "tag"
 no_includes = true
@@ -7,6 +18,3 @@ cpp_compat = true
 
 [enum]
 prefix_with_name = true
-
-
-

src/header/monetary/strfmon.rs

@@ -14,6 +14,7 @@ use libm::{fabs, pow, round, trunc};
 /// Returns:
 /// - The number of characters written (excluding the null terminator), or -1 if
 ///   an error occurs (e.g., invalid input, buffer overflow)
+#[unsafe(no_mangle)]
 pub unsafe extern "C" fn strfmon(
     s: *mut c_char,        // Output buffer
     maxsize: usize,        // Maximum size of the buffer