[libc] Implement getitimer and setitimer, add proxy headers for itimerval (#134773)

#133983

Author: tszhin-swe

libc/config/linux/aarch64/entrypoints.txt

@@ -363,6 +363,10 @@ set(TARGET_LIBC_ENTRYPOINTS
     # sys/uio.h entrypoints
     libc.src.sys.uio.writev
     libc.src.sys.uio.readv
+
+    # sys/time.h entrypoints
+    libc.src.sys.time.setitimer
+    libc.src.sys.time.getitimer
 )
 
 if(LLVM_LIBC_INCLUDE_SCUDO)

libc/config/linux/arm/entrypoints.txt

@@ -185,6 +185,9 @@ set(TARGET_LIBC_ENTRYPOINTS
     # libc.src.sys.epoll.epoll_pwait
     # libc.src.sys.epoll.epoll_pwait2
 
+    # sys/time.h entrypoints
+    libc.src.sys.time.setitimer
+    libc.src.sys.time.getitimer
 )
 
 if(LLVM_LIBC_FULL_BUILD)

libc/config/linux/x86_64/entrypoints.txt

@@ -368,6 +368,10 @@ set(TARGET_LIBC_ENTRYPOINTS
     # sys/uio.h entrypoints
     libc.src.sys.uio.writev
     libc.src.sys.uio.readv
+
+    # sys/time.h entrypoints
+    libc.src.sys.time.setitimer
+    libc.src.sys.time.getitimer
 )
 
 if(LLVM_LIBC_INCLUDE_SCUDO)

libc/hdr/types/CMakeLists.txt

@@ -190,6 +190,15 @@ add_proxy_header_library(
     libc.include.sys_time
 )
 
+add_proxy_header_library(
+  struct_itimerval
+  HDRS
+    struct_itimerval.h
+  FULL_BUILD_DEPENDS
+    libc.include.llvm-libc-types.struct_itimerval
+    libc.include.sys_time
+)
+
 add_proxy_header_library(
   pid_t
   HDRS

libc/hdr/types/struct_itimerval.h

@@ -0,0 +1,21 @@
+//===-- Proxy for struct itimerval ----------------------------------------===//
+//
+// 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_STRUCT_ITIMERVAL_H
+#define LLVM_LIBC_HDR_TYPES_STRUCT_ITIMERVAL_H
+
+#ifdef LIBC_FULL_BUILD
+
+#include "include/llvm-libc-types/struct_itimerval.h"
+
+#else
+
+#include <sys/time.h>
+
+#endif // LIBC_FULL_BUILD
+
+#endif // LLVM_LIBC_HDR_TYPES_STRUCT_ITIMERVAL_H

libc/include/llvm-libc-types/CMakeLists.txt

@@ -77,6 +77,7 @@ add_header(struct_pollfd HDR struct_pollfd.h)
 add_header(struct_rlimit HDR struct_rlimit.h DEPENDS .rlim_t)
 add_header(struct_sched_param HDR struct_sched_param.h)
 add_header(struct_timeval HDR struct_timeval.h DEPENDS .suseconds_t .time_t)
+add_header(struct_itimerval HDR struct_itimerval.h DEPENDS .struct_timeval)
 add_header(struct_rusage HDR struct_rusage.h DEPENDS .struct_timeval)
 add_header(union_sigval HDR union_sigval.h)
 add_header(siginfo_t HDR siginfo_t.h DEPENDS .union_sigval .pid_t .uid_t .clock_t)

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

@@ -0,0 +1,19 @@
+//===-- Definition of struct itimerval ------------------------------------===//
+//
+// 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_STRUCT_ITIMERVAL_H
+#define LLVM_LIBC_TYPES_STRUCT_ITIMERVAL_H
+
+#include "struct_timeval.h"
+
+struct itimerval {
+  struct timeval it_interval; /* Interval for periodic timer */
+  struct timeval it_value;    /* Time until next expiration */
+};
+
+#endif // LLVM_LIBC_TYPES_STRUCT_ITIMERVAL_H

libc/include/sys/time.yaml

@@ -4,6 +4,7 @@ standards: Linux
 macros: []
 types:
   - type_name: struct_timeval
+  - type_name: struct_itimerval
 enums: []
 objects: []
 functions:
@@ -12,3 +13,20 @@ functions:
     arguments:
       - type: const char*
       - type: const struct timeval*
+
+  - name: setitimer
+    standards:
+      - POSIX
+    return_type: int
+    arguments:
+      - type: int
+      - type: const struct itimerval *__restrict
+      - type: struct itimerval *__restrict
+  
+  - name: getitimer
+    standards:
+      - POSIX
+    return_type: int
+    arguments:
+      - type: int
+      - type: struct itimerval *

libc/src/sys/time/CMakeLists.txt

@@ -8,3 +8,17 @@ add_entrypoint_object(
   DEPENDS
     .${LIBC_TARGET_OS}.utimes
 )
+
+add_entrypoint_object(
+  setitimer
+  ALIAS
+  DEPENDS
+  .${LIBC_TARGET_OS}.setitimer 
+)
+
+add_entrypoint_object(
+  getitimer
+  ALIAS
+  DEPENDS
+    .${LIBC_TARGET_OS}.getitimer 
+)

libc/src/sys/time/getitimer.h

@@ -0,0 +1,19 @@
+//===-- Implementation header for getitimer -------------------------------===//
+//
+// 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_SYS_TIME_GETITIMER_H
+#define LLVM_LIBC_SRC_SYS_TIME_GETITIMER_H
+
+#include "hdr/types/struct_itimerval.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+int getitimer(int which, struct itimerval *curr_value);
+} // namespace LIBC_NAMESPACE_DECL
+
+#endif // LLVM_LIBC_SRC_SYS_TIME_GETITIMER_H