[libc] Add entrypoint for iswxdigit (#185574)

This PR intends to add entrypoints and some smoke tests for `iswxdigit`
function

Changes made are :-
- Added entrypoint for `iswxdigit` in wctype.yaml
- Added CMake entrypoint object for `iswxdigit`
- Added Header and implementation in `iswxdigit.h` and `iswxdigit.cpp`
- Added test for `iswxdigit` in iswxdigit_test.cpp
- Added `iswxdigit` in entrypoints.txt for available platforms 

Tested using = `ninja libc.test.src.wctype.iswxdigit_test.__unit__`
passes all tests

part of #185136

libc/config/baremetal/arm/entrypoints.txt

@@ -305,6 +305,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 
     # internal entrypoints
     libc.startup.baremetal.init

libc/config/baremetal/riscv/entrypoints.txt

@@ -302,6 +302,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 
     # internal entrypoints
     libc.startup.baremetal.init

libc/config/darwin/aarch64/entrypoints.txt

@@ -108,6 +108,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 )
 
 if(LLVM_LIBC_FULL_BUILD)

libc/config/linux/aarch64/entrypoints.txt

@@ -375,6 +375,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 
     # sys/uio.h entrypoints
     libc.src.sys.uio.writev

libc/config/linux/arm/entrypoints.txt

@@ -200,6 +200,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 )
 
 if(LLVM_LIBC_FULL_BUILD)

libc/config/linux/riscv/entrypoints.txt

@@ -379,6 +379,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 
     # sys/uio.h entrypoints
     libc.src.sys.uio.writev

libc/config/linux/x86_64/entrypoints.txt

@@ -424,6 +424,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 
     # sys/uio.h entrypoints
     libc.src.sys.uio.writev

libc/config/windows/entrypoints.txt

@@ -113,6 +113,7 @@ set(TARGET_LIBC_ENTRYPOINTS
     libc.src.wctype.iswlower
     libc.src.wctype.iswspace
     libc.src.wctype.iswblank
+    libc.src.wctype.iswxdigit
 )
 
 set(TARGET_LIBM_ENTRYPOINTS

libc/include/wctype.yaml

@@ -38,3 +38,9 @@ functions:
     return_type: int
     arguments:
       - type: wint_t
+  - name: iswxdigit
+    standards:
+      - stdc
+    return_type: int
+    arguments:
+      - type: wint_t

libc/src/wctype/CMakeLists.txt

@@ -73,3 +73,14 @@ add_entrypoint_object(
     libc.src.__support.wctype_utils
     libc.hdr.types.wint_t
 )
+
+add_entrypoint_object(
+  iswxdigit
+  SRCS
+    iswxdigit.cpp
+  HDRS
+    iswxdigit.h
+  DEPENDS
+    libc.src.__support.wctype_utils
+    libc.hdr.types.wint_t
+)

libc/src/wctype/iswxdigit.cpp

@@ -0,0 +1,21 @@
+//===-- Implementation of iswxdigit ---------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/wctype/iswxdigit.h"
+#include "src/__support/common.h"
+#include "src/__support/wctype_utils.h"
+
+#include "hdr/types/wint_t.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+LLVM_LIBC_FUNCTION(int, iswxdigit, (wint_t c)) {
+  return internal::isxdigit(static_cast<wchar_t>(c));
+}
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/wctype/iswxdigit.h

@@ -0,0 +1,21 @@
+//===-- Implementation header for iswxdigit ---------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_LIBC_SRC_WCTYPE_ISWXDIGIT_H
+#define LLVM_LIBC_SRC_WCTYPE_ISWXDIGIT_H
+
+#include "hdr/types/wint_t.h"
+#include "src/__support/common.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+int iswxdigit(wint_t c);
+
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_WCTYPE_ISWXDIGIT_H

libc/test/src/wctype/CMakeLists.txt

@@ -71,3 +71,13 @@ add_libc_test(
   DEPENDS
     libc.src.wctype.iswblank
 )
+
+add_libc_test(
+  iswxdigit_test
+  SUITE
+    libc_wctype_unittests
+  SRCS
+    iswxdigit_test.cpp
+  DEPENDS
+    libc.src.wctype.iswxdigit
+)

libc/test/src/wctype/iswxdigit_test.cpp

@@ -0,0 +1,25 @@
+//===-- Unittests for iswxdigit -------------------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/wctype/iswxdigit.h"
+#include "test/UnitTest/Test.h"
+
+TEST(LlvmLibciswxdigit, SimpleTest) {
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'1'), 0);
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'2'), 0);
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'0'), 0);
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'a'), 0);
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'B'), 0);
+  EXPECT_NE(LIBC_NAMESPACE::iswxdigit(L'F'), 0);
+
+  EXPECT_EQ(LIBC_NAMESPACE::iswxdigit(L'g'), 0);
+  EXPECT_EQ(LIBC_NAMESPACE::iswxdigit(L'h'), 0);
+  EXPECT_EQ(LIBC_NAMESPACE::iswxdigit(L'é'), 0);
+  EXPECT_EQ(LIBC_NAMESPACE::iswxdigit(L' '), 0);
+  EXPECT_EQ(LIBC_NAMESPACE::iswxdigit(L'!'), 0);
+}