[libc] Add ctime_s

Resolves #110548 Definition: ```c++ int ctime_s(char *buffer, rsize_t buffer_size, const time_t *t_ptr); ```

Author: Rajveer100

libc/config/baremetal/arm/entrypoints.txt

@@ -206,6 +206,7 @@ set(TARGET_LIBC_ENTRYPOINTS
  libc.src.time.asctime_r
  libc.src.time.ctime
  libc.src.time.ctime_r
+ libc.src.time.ctime_s
  libc.src.time.difftime
  libc.src.time.gmtime
  libc.src.time.gmtime_r

libc/config/baremetal/riscv/entrypoints.txt

@@ -202,6 +202,7 @@ set(TARGET_LIBC_ENTRYPOINTS
  libc.src.time.asctime_r
  libc.src.time.ctime
  libc.src.time.ctime_r
+ libc.src.time.ctime_s
  libc.src.time.difftime
  libc.src.time.gmtime
  libc.src.time.gmtime_r

libc/config/linux/aarch64/entrypoints.txt

@@ -1010,6 +1010,7 @@ if(LLVM_LIBC_FULL_BUILD)
  libc.src.time.asctime_r
  libc.src.time.ctime
  libc.src.time.ctime_r
+ libc.src.time.ctime_s
  libc.src.time.clock
  libc.src.time.clock_gettime
  libc.src.time.difftime

libc/config/linux/riscv/entrypoints.txt

@@ -941,6 +941,7 @@ if(LLVM_LIBC_FULL_BUILD)
  libc.src.time.asctime_r
  libc.src.time.ctime
  libc.src.time.ctime_r
+ libc.src.time.ctime_s
  libc.src.time.clock
  libc.src.time.clock_gettime
  libc.src.time.difftime

libc/config/linux/x86_64/entrypoints.txt

@@ -1095,6 +1095,7 @@ if(LLVM_LIBC_FULL_BUILD)
  libc.src.time.asctime_r
  libc.src.time.ctime
  libc.src.time.ctime_r
+ libc.src.time.ctime_s
  libc.src.time.clock
  libc.src.time.clock_gettime
  libc.src.time.difftime

libc/docs/headers/time.rst

@@ -59,6 +59,8 @@ Implementation Status
 +---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
 | ctime_r | |check| | |check| | | |check| | | | | | | | | |
 +---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
+| ctime_s | |check| | |check| | | |check| | | | | | | | | |
++---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
 | clock | |check| | |check| | | |check| | | | | | | | | |
 +---------------------+---------+---------+---------+-----------------+---------+---------+---------+---------+---------+---------+---------+---------+
 | clock_getcpuclockid | | | | | | | | | | | | |

libc/hdr/types/errno_t.h

@@ -0,0 +1,22 @@
+//===-- Proxy for errno_t -------------------------------------------------===//
+//
+// 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_HDR_TYPES_ERRNO_T_H
+#define LLVM_LIBC_HDR_TYPES_ERRNO_T_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/errno_t.h"
+
+#else
+
+#define __STDC_WANT_LIB_EXT1__ 1
+#include <errno.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_ERRNO_T_H

libc/hdr/types/rsize_t.h

@@ -0,0 +1,23 @@
+//===-- Proxy for rsize_t -------------------------------------------------===//
+//
+// 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_HDR_TYPES_RSIZE_T_H
+#define LLVM_LIBC_HDR_TYPES_RSIZE_T_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/rsize_t.h"
+
+#else
+
+#define __need_rsize_t
+#include <stddef.h>
+#undef __need_rsize_t
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_RSIZE_T_H

libc/include/llvm-libc-types/errno_t.h

@@ -0,0 +1,14 @@
+//===-- Definition of errno_t type ----------------------------------------===//
+//
+// 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_TYPES_ERRNO_T_H
+#define LLVM_LIBC_TYPES_ERRNO_T_H
+
+typedef int errno_t;
+
+#endif // LLVM_LIBC_TYPES_ERRNO_T_H

libc/include/llvm-libc-types/rsize_t.h

@@ -0,0 +1,16 @@
+//===-- Definition of rsize_t type ----------------------------------------===//
+//
+// 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_TYPES_RSIZE_T_H
+#define LLVM_LIBC_TYPES_RSIZE_T_H
+
+#include "size_t.h"
+
+typedef size_t rsize_t;
+
+#endif // LLVM_LIBC_TYPES_RSIZE_T_H