[libc] Enable utimes function for riscv

RV32 uses SYS_utimensat_time64 instead of SYS_utimensat but the call is the same.
llvm · mikhailramalho · May 13, 2025 · May 8, 2025 · May 9, 2025 · May 13, 2025
commit 5376c0d2dfa0f8f99c123a35c9b640d66d9cbd93
diff --git a/libc/config/linux/riscv/entrypoints.txt b/libc/config/linux/riscv/entrypoints.txt
@@ -290,7 +290,7 @@ set(TARGET_LIBC_ENTRYPOINTS
    libc.src.sys.statvfs.statvfs

    # sys/utimes.h entrypoints
-    # libc.src.sys.time.utimes
+    libc.src.sys.time.utimes

    # sys/utsname.h entrypoints
    libc.src.sys.utsname.uname

diff --git a/libc/include/sys/syscall.h.def b/libc/include/sys/syscall.h.def
@@ -2301,6 +2301,10 @@
 #define SYS_utimes __NR_utimes
 #endif

+#ifdef __NR_utimensat_time64
+#define SYS_utimensat_time64 __NR_utimensat_time64
+#endif
+
 #ifdef __NR_utrap_install
 #define SYS_utrap_install __NR_utrap_install
 #endif

diff --git a/libc/src/sys/time/linux/utimes.cpp b/libc/src/sys/time/linux/utimes.cpp
@@ -10,6 +10,7 @@

 #include "hdr/fcntl_macros.h"
 #include "hdr/types/struct_timeval.h"
+#include "hdr/types/struct_timespec.h"

 #include "src/__support/OSUtil/syscall.h"
 #include "src/__support/common.h"
@@ -20,14 +21,24 @@

 namespace LIBC_NAMESPACE_DECL {

+#if SYS_utimes
+constexpr auto UTIMES_SYSCALL_ID = SYS_utimes;
+#elif defined(SYS_utimensat)
+constexpr auto UTIMES_SYSCALL_ID = SYS_utimensat;
+#elif defined(SYS_utimensat_time64)
+constexpr auto UTIMES_SYSCALL_ID = SYS_utimensat_time64;
+#else
+#error "utimes, utimensat, utimensat_time64,  syscalls not available."
+#endif
+
 LLVM_LIBC_FUNCTION(int, utimes,
                   (const char *path, const struct timeval times[2])) {
  int ret;

 #ifdef SYS_utimes
  // No need to define a timespec struct, use the syscall directly.
-  ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_utimes, path, times);
-#elif defined(SYS_utimensat)
+  ret = LIBC_NAMESPACE::syscall_impl<int>(UTIMES_SYSCALL_ID, path, times);
+#elif defined(SYS_utimensat) || defined(SYS_utimensat_time64)
  // the utimensat syscall requires a timespec struct, not timeval.
  struct timespec ts[2];
  struct timespec *ts_ptr = nullptr; // default value if times is nullptr
@@ -59,11 +70,8 @@ LLVM_LIBC_FUNCTION(int, utimes,

  // utimensat syscall.
  // flags=0 means don't follow symlinks (like utimes)
-  ret = LIBC_NAMESPACE::syscall_impl<int>(SYS_utimensat, AT_FDCWD, path, ts_ptr,
-                                          0);
-
-#else
-#error "utimensat and utimes syscalls not available."
+  ret = LIBC_NAMESPACE::syscall_impl<int>(UTIMES_SYSCALL_ID, AT_FDCWD, path,
+                                          ts_ptr, 0);
 #endif // SYS_utimensat

  if (ret < 0) {