[libc] Add a definition of pthread_attr_t and its getters and setters.

Not all attributes have been added to phtread_attr_t in this patch. They
will be added gradually in future patches.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D123423

32 files changed, 816 insertions, 2 deletions

diff --git a/libc/config/linux/aarch64/entrypoints.txt b/libc/config/linux/aarch64/entrypoints.txt
index aa66c0d040a4..eaedb4237ed1 100644
--- a/libc/config/linux/aarch64/entrypoints.txt
+++ b/libc/config/linux/aarch64/entrypoints.txt
@@ -230,6 +230,16 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.threads.thrd_join
 
     # pthread.h entrypoints
+    libc.src.pthread.pthread_attr_destroy
+    libc.src.pthread.pthread_attr_init
+    libc.src.pthread.pthread_attr_getdetachstate
+    libc.src.pthread.pthread_attr_getguardsize
+    libc.src.pthread.pthread_attr_getstack
+    libc.src.pthread.pthread_attr_getstacksize
+    libc.src.pthread.pthread_attr_setdetachstate
+    libc.src.pthread.pthread_attr_setguardsize
+    libc.src.pthread.pthread_attr_setstack
+    libc.src.pthread.pthread_attr_setstacksize
     libc.src.pthread.pthread_mutexattr_destroy
     libc.src.pthread.pthread_mutexattr_init
     libc.src.pthread.pthread_mutexattr_getpshared
diff --git a/libc/config/linux/api.td b/libc/config/linux/api.td
index 9d2f142ef43a..ed2b3b6b4ece 100644
--- a/libc/config/linux/api.td
+++ b/libc/config/linux/api.td
@@ -238,7 +238,10 @@ def ThreadsAPI : PublicAPI<"threads.h"> {
 }
 
 def PThreadAPI : PublicAPI<"pthread.h"> {
-  let Types = ["pthread_mutexattr_t"];
+  let Types = [
+      "pthread_attr_t",
+      "pthread_mutexattr_t"
+  ];
 }
 
 def UniStdAPI : PublicAPI<"unistd.h"> {
diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index c5c5e5046de2..5fc5d19f7520 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -223,6 +223,17 @@ if(LLVM_LIBC_FULL_BUILD)
     # libc.src.assert.__assert_fail
 
     # pthread.h entrypoints
+    libc.src.pthread.pthread_attr_destroy
+    libc.src.pthread.pthread_attr_init
+    libc.src.pthread.pthread_attr_getdetachstate
+    libc.src.pthread.pthread_attr_getguardsize
+    libc.src.pthread.pthread_attr_getstack
+    libc.src.pthread.pthread_attr_getstacksize
+    libc.src.pthread.pthread_attr_setdetachstate
+    libc.src.pthread.pthread_attr_setguardsize
+    libc.src.pthread.pthread_attr_setstack
+    libc.src.pthread.pthread_attr_setstacksize
+    libc.src.pthread.pthread_attr_init
     libc.src.pthread.pthread_mutexattr_destroy
     libc.src.pthread.pthread_mutexattr_init
     libc.src.pthread.pthread_mutexattr_getpshared
diff --git a/libc/include/CMakeLists.txt b/libc/include/CMakeLists.txt
index efe9e8107ee7..9a4a888bd2d7 100644
--- a/libc/include/CMakeLists.txt
+++ b/libc/include/CMakeLists.txt
@@ -161,6 +161,7 @@ add_gen_header(
   GEN_HDR pthread.h
   DEPENDS
     .llvm_libc_common_h
+    .llvm-libc-types.pthread_attr_t
     .llvm-libc-types.pthread_mutexattr_t
 )
 
diff --git a/libc/include/llvm-libc-types/CMakeLists.txt b/libc/include/llvm-libc-types/CMakeLists.txt
index 77a86fe25619..9ddeeb73f499 100644
--- a/libc/include/llvm-libc-types/CMakeLists.txt
+++ b/libc/include/llvm-libc-types/CMakeLists.txt
@@ -18,6 +18,7 @@ add_header(mode_t HDR mode_t.h)
 add_header(mtx_t HDR mtx_t.h DEPENDS .__futex_word .__mutex_type)
 add_header(off_t HDR off_t.h)
 add_header(once_flag HDR once_flag.h DEPENDS .__futex_word)
+add_header(pthread_attr_t HDR pthread_attr_t.h)
 add_header(pthread_mutexattr_t HDR pthread_mutexattr_t.h)
 add_header(size_t HDR size_t.h)
 add_header(ssize_t HDR ssize_t.h)
diff --git a/libc/include/llvm-libc-types/pthread_attr_t.h b/libc/include/llvm-libc-types/pthread_attr_t.h
new file mode 100644
index 000000000000..7bf8a5402f28
--- /dev/null
+++ b/libc/include/llvm-libc-types/pthread_attr_t.h
@@ -0,0 +1,21 @@
+//===-- Definition of pthread_attr_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_PTHREAD_ATTR_T_H
+#define __LLVM_LIBC_TYPES_PTHREAD_ATTR_T_H
+
+#include <llvm-libc-types/size_t.h>
+
+typedef struct {
+  int __detachstate;
+  void *__stack;
+  size_t __stacksize;
+  size_t __guardsize;
+} pthread_attr_t;
+
+#endif // __LLVM_LIBC_TYPES_PTHREAD_ATTR_T_H
diff --git a/libc/include/pthread.h.def b/libc/include/pthread.h.def
index 9de3da4b5dee..60f257e7078d 100644
--- a/libc/include/pthread.h.def
+++ b/libc/include/pthread.h.def
@@ -11,7 +11,12 @@
 
 #include <__llvm-libc-common.h>
 
+#define PTHREAD_STACK_MIN (1 << 14) // 16KB
+
 enum {
+  PTHREAD_CREATE_JOINABLE = 0x0,
+  PTHREAD_CREATE_DETACHED = 0x1,
+
   PTHREAD_MUTEX_NORMAL = 0x0,
   PTHREAD_MUTEX_ERRORCHECK = 0x1,
   PTHREAD_MUTEX_RECURSIVE = 0x2,
diff --git a/libc/spec/posix.td b/libc/spec/posix.td
index 882ccf5e6d72..13b4ed4ce49d 100644
--- a/libc/spec/posix.td
+++ b/libc/spec/posix.td
@@ -20,6 +20,13 @@ def POSIX : StandardSpec<"POSIX"> {
   NamedType ModeTType = NamedType<"mode_t">;
   NamedType OffTType = NamedType<"off_t">;
   NamedType SSizeTType = NamedType<"ssize_t">;
+
+  NamedType PThreadAttrTType = NamedType<"pthread_attr_t">;
+  PtrType PThreadAttrTPtr = PtrType<PThreadAttrTType>;
+  RestrictedPtrType RestrictedPThreadAttrTPtr = RestrictedPtrType<PThreadAttrTType>;
+  ConstType ConstPThreadAttrTPtr = ConstType<PThreadAttrTPtr>;
+  ConstType ConstRestrictedPThreadAttrTPtr = ConstType<RestrictedPThreadAttrTPtr>;
+
   NamedType PThreadMutexAttrTType = NamedType<"pthread_mutexattr_t">;
   PtrType PThreadMutexAttrTPtr = PtrType<PThreadMutexAttrTType>;
   RestrictedPtrType RestrictedPThreadMutexAttrTPtr = RestrictedPtrType<PThreadMutexAttrTType>;
@@ -379,10 +386,60 @@ def POSIX : StandardSpec<"POSIX"> {
   HeaderSpec PThread = HeaderSpec<
     "pthread.h",
     [], // Macros
-    [PThreadMutexAttrTType], // Types
+    [PThreadAttrTType, PThreadMutexAttrTType], // Types
     [], // Enumerations
     [
       FunctionSpec<
+          "pthread_attr_init",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_destroy",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_getdetachstate",
+          RetValSpec<IntType>,
+          [ArgSpec<ConstPThreadAttrTPtr>, ArgSpec<IntPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_setdetachstate",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>, ArgSpec<IntType>]
+      >,
+      FunctionSpec<
+          "pthread_attr_getguardsize",
+          RetValSpec<IntType>,
+          [ArgSpec<ConstRestrictedPThreadAttrTPtr>, ArgSpec<RestrictedSizeTPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_setguardsize",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>, ArgSpec<SizeTType>]
+      >,
+      FunctionSpec<
+          "pthread_attr_getstacksize",
+          RetValSpec<IntType>,
+          [ArgSpec<ConstRestrictedPThreadAttrTPtr>, ArgSpec<RestrictedSizeTPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_setstacksize",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>, ArgSpec<SizeTType>]
+      >,
+      FunctionSpec<
+          "pthread_attr_getstack",
+          RetValSpec<IntType>,
+          [ArgSpec<ConstRestrictedPThreadAttrTPtr>, ArgSpec<RestrictedVoidPtrPtr>, ArgSpec<RestrictedSizeTPtr>]
+      >,
+      FunctionSpec<
+          "pthread_attr_setstack",
+          RetValSpec<IntType>,
+          [ArgSpec<PThreadAttrTPtr>, ArgSpec<VoidPtr>, ArgSpec<SizeTType>]
+      >,
+      FunctionSpec<
           "pthread_mutexattr_init",
           RetValSpec<IntType>,
           [ArgSpec<PThreadMutexAttrTPtr>]
diff --git a/libc/spec/spec.td b/libc/spec/spec.td
index 2261043a726c..5c947e4a17ca 100644
--- a/libc/spec/spec.td
+++ b/libc/spec/spec.td
@@ -50,8 +50,14 @@ def CharType : NamedType<"char">;
 
 // Common types
 def VoidPtr : PtrType<VoidType>;
+def VoidPtrPtr : PtrType<VoidPtr>;
+def RestrictedVoidPtrPtr : RestrictedPtrType<VoidPtr>;
 def ConstVoidPtr : ConstType<VoidPtr>;
+
 def SizeTType : NamedType<"size_t">;
+def SizeTPtr : PtrType<SizeTType>;
+def RestrictedSizeTPtr : RestrictedPtrType<SizeTType>;
+
 def LongDoublePtr : PtrType<LongDoubleType>;
 
 def IntMaxTType : NamedType<"intmax_t">;
diff --git a/libc/src/pthread/CMakeLists.txt b/libc/src/pthread/CMakeLists.txt
index 22d61c85af27..5d447baef08a 100644
--- a/libc/src/pthread/CMakeLists.txt
+++ b/libc/src/pthread/CMakeLists.txt
@@ -1,3 +1,103 @@
+add_entrypoint_object(
+  pthread_attr_init
+  SRCS
+    pthread_attr_init.cpp
+  HDRS
+    pthread_attr_init.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_destroy
+  SRCS
+    pthread_attr_destroy.cpp
+  HDRS
+    pthread_attr_destroy.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_getdetachstate
+  SRCS
+    pthread_attr_getdetachstate.cpp
+  HDRS
+    pthread_attr_getdetachstate.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_setdetachstate
+  SRCS
+    pthread_attr_setdetachstate.cpp
+  HDRS
+    pthread_attr_setdetachstate.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_getguardsize
+  SRCS
+    pthread_attr_getguardsize.cpp
+  HDRS
+    pthread_attr_getguardsize.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_setguardsize
+  SRCS
+    pthread_attr_setguardsize.cpp
+  HDRS
+    pthread_attr_setguardsize.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_getstacksize
+  SRCS
+    pthread_attr_getstacksize.cpp
+  HDRS
+    pthread_attr_getstacksize.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_setstacksize
+  SRCS
+    pthread_attr_setstacksize.cpp
+  HDRS
+    pthread_attr_setstacksize.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_getstack
+  SRCS
+    pthread_attr_getstack.cpp
+  HDRS
+    pthread_attr_getstack.h
+  DEPENDS
+    libc.include.pthread
+)
+
+add_entrypoint_object(
+  pthread_attr_setstack
+  SRCS
+    pthread_attr_setstack.cpp
+  HDRS
+    pthread_attr_setstack.h
+  DEPENDS
+    libc.include.pthread
+)
+
 add_header_library(
   pthread_mutexattr
   HDRS
diff --git a/libc/src/pthread/pthread_attr_destroy.cpp b/libc/src/pthread/pthread_attr_destroy.cpp
new file mode 100644
index 000000000000..592d002483d8
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_destroy.cpp
@@ -0,0 +1,22 @@
+//===-- Implementation of the pthread_attr_destroy ------------------------===//
+//
+// 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 "pthread_attr_destroy.h"
+
+#include "src/__support/common.h"
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_destroy, (pthread_attr_t * attr)) {
+  // There is nothing to cleanup.
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_destroy.h b/libc/src/pthread/pthread_attr_destroy.h
new file mode 100644
index 000000000000..5d01bc8d782d
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_destroy.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_destroy ----------*- 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_PTHREAD_PTHREAD_ATTR_DESTROY_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_DESTROY_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_destroy(pthread_attr_t *attr);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_DESTROY_H
diff --git a/libc/src/pthread/pthread_attr_getdetachstate.cpp b/libc/src/pthread/pthread_attr_getdetachstate.cpp
new file mode 100644
index 000000000000..18f4637e1c8f
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getdetachstate.cpp
@@ -0,0 +1,23 @@
+//===-- Implementation of the pthread_attr_getdetachstate -----------------===//
+//
+// 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 "pthread_attr_getdetachstate.h"
+
+#include "src/__support/common.h"
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_getdetachstate,
+                   (const pthread_attr_t *attr, int *detachstate)) {
+  *detachstate = attr->__detachstate;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_getdetachstate.h b/libc/src/pthread/pthread_attr_getdetachstate.h
new file mode 100644
index 000000000000..fd5ee886daeb
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getdetachstate.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_getdetachstate ---*- 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_PTHREAD_PTHREAD_ATTR_GETDETACHSTATE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETDETACHSTATE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_getdetachstate(const pthread_attr_t *attr, int *detach_state);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETDETACHSTATE_H
diff --git a/libc/src/pthread/pthread_attr_getguardsize.cpp b/libc/src/pthread/pthread_attr_getguardsize.cpp
new file mode 100644
index 000000000000..79d80feed713
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getguardsize.cpp
@@ -0,0 +1,24 @@
+//===-- Implementation of the pthread_attr_getguardsize -----------------===//
+//
+// 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 "pthread_attr_getguardsize.h"
+
+#include "src/__support/common.h"
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_getguardsize,
+                   (const pthread_attr_t *__restrict attr,
+                    size_t *__restrict guardsize)) {
+  *guardsize = attr->__guardsize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_getguardsize.h b/libc/src/pthread/pthread_attr_getguardsize.h
new file mode 100644
index 000000000000..61072b9350fe
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getguardsize.h
@@ -0,0 +1,21 @@
+//===-- Implementation header for pthread_attr_getguardsize -----*- 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_PTHREAD_PTHREAD_ATTR_GETGUARDSIZE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETGUARDSIZE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_getguardsize(const pthread_attr_t *__restrict attr,
+                              size_t *__restrict guardsize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETGUARDSIZE_H
diff --git a/libc/src/pthread/pthread_attr_getstack.cpp b/libc/src/pthread/pthread_attr_getstack.cpp
new file mode 100644
index 000000000000..fea940489e6f
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getstack.cpp
@@ -0,0 +1,25 @@
+//===-- Implementation of the pthread_attr_getstack -----------------===//
+//
+// 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 "pthread_attr_getstack.h"
+
+#include "src/__support/common.h"
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_getstack,
+                   (const pthread_attr_t *__restrict attr,
+                    void **__restrict stack, size_t *__restrict stacksize)) {
+  *stack = attr->__stack;
+  *stacksize = attr->__stacksize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_getstack.h b/libc/src/pthread/pthread_attr_getstack.h
new file mode 100644
index 000000000000..d0164738349b
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getstack.h
@@ -0,0 +1,22 @@
+//===-- Implementation header for pthread_attr_getstack ---------*- 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_PTHREAD_PTHREAD_ATTR_GETSTACK_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETSTACK_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_getstack(const pthread_attr_t *__restrict attr,
+                          void **__restrict stack,
+                          size_t *__restrict stacksize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETSTACK_H
diff --git a/libc/src/pthread/pthread_attr_getstacksize.cpp b/libc/src/pthread/pthread_attr_getstacksize.cpp
new file mode 100644
index 000000000000..2b33d6fc8a44
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getstacksize.cpp
@@ -0,0 +1,24 @@
+//===-- Implementation of the pthread_attr_getstacksize -----------------===//
+//
+// 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 "pthread_attr_getstacksize.h"
+
+#include "src/__support/common.h"
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_getstacksize,
+                   (const pthread_attr_t *__restrict attr,
+                    size_t *__restrict stacksize)) {
+  *stacksize = attr->__stacksize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_getstacksize.h b/libc/src/pthread/pthread_attr_getstacksize.h
new file mode 100644
index 000000000000..cb27a5e1927e
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_getstacksize.h
@@ -0,0 +1,21 @@
+//===-- Implementation header for pthread_attr_getstacksize -----*- 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_PTHREAD_PTHREAD_ATTR_GETSTACKSIZE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETSTACKSIZE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_getstacksize(const pthread_attr_t *__restrict attr,
+                              size_t *__restrict stacksize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_GETSTACKSIZE_H
diff --git a/libc/src/pthread/pthread_attr_init.cpp b/libc/src/pthread/pthread_attr_init.cpp
new file mode 100644
index 000000000000..84b352022874
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_init.cpp
@@ -0,0 +1,28 @@
+//===-- Implementation of the pthread_attr_init ---------------------------===//
+//
+// 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 "pthread_attr_init.h"
+
+#include "src/__support/common.h"
+
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_init, (pthread_attr_t * attr)) {
+  *attr = pthread_attr_t{
+      false,         // Not detached
+      nullptr,       // Let the thread manage its stack
+      1 << 16,       // 64KB stack size
+      EXEC_PAGESIZE, // Default page size for the guard size.
+  };
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_init.h b/libc/src/pthread/pthread_attr_init.h
new file mode 100644
index 000000000000..609e65381db7
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_init.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_init -------------*- 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_PTHREAD_PTHREAD_ATTR_INIT_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_INIT_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_init(pthread_attr_t *attr);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_INIT_H
diff --git a/libc/src/pthread/pthread_attr_setdetachstate.cpp b/libc/src/pthread/pthread_attr_setdetachstate.cpp
new file mode 100644
index 000000000000..e136538e054f
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setdetachstate.cpp
@@ -0,0 +1,27 @@
+//===-- Implementation of the pthread_attr_setdetachstate -----------------===//
+//
+// 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 "pthread_attr_setdetachstate.h"
+
+#include "src/__support/common.h"
+
+#include <errno.h>
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_setdetachstate,
+                   (pthread_attr_t * attr, int detachstate)) {
+  if (detachstate != PTHREAD_CREATE_DETACHED &&
+      detachstate != PTHREAD_CREATE_JOINABLE)
+    return EINVAL;
+  attr->__detachstate = detachstate;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_setdetachstate.h b/libc/src/pthread/pthread_attr_setdetachstate.h
new file mode 100644
index 000000000000..a8f586619f53
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setdetachstate.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_setdetachstate ---*- 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_PTHREAD_PTHREAD_ATTR_SETDETACHSTATE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETDETACHSTATE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_setdetachstate(pthread_attr_t *attr, int detach_state);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETDETACHSTATE_H
diff --git a/libc/src/pthread/pthread_attr_setguardsize.cpp b/libc/src/pthread/pthread_attr_setguardsize.cpp
new file mode 100644
index 000000000000..dd2584a55292
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setguardsize.cpp
@@ -0,0 +1,27 @@
+//===-- Implementation of the pthread_attr_setguardsize -----------------===//
+//
+// 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 "pthread_attr_setguardsize.h"
+
+#include "src/__support/common.h"
+
+#include <errno.h>
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_setguardsize,
+                   (pthread_attr_t *__restrict attr, size_t guardsize)) {
+  if (guardsize % EXEC_PAGESIZE != 0)
+    return EINVAL;
+  attr->__guardsize = guardsize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_setguardsize.h b/libc/src/pthread/pthread_attr_setguardsize.h
new file mode 100644
index 000000000000..d9e159874f26
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setguardsize.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_setguardsize -----*- 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_PTHREAD_PTHREAD_ATTR_SETGUARDSIZE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETGUARDSIZE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_setguardsize(pthread_attr_t *attr, size_t guardsize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETGUARDSIZE_H
diff --git a/libc/src/pthread/pthread_attr_setstack.cpp b/libc/src/pthread/pthread_attr_setstack.cpp
new file mode 100644
index 000000000000..60a7a40326ef
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setstack.cpp
@@ -0,0 +1,33 @@
+//===-- Implementation of the pthread_attr_setstack -----------------===//
+//
+// 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 "pthread_attr_setstack.h"
+
+#include "src/__support/common.h"
+
+#include <errno.h>
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <pthread.h>
+#include <stdint.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_setstack,
+                   (pthread_attr_t *__restrict attr, void *stack,
+                    size_t stacksize)) {
+  if (stacksize < PTHREAD_STACK_MIN)
+    return EINVAL;
+  uintptr_t stackaddr = reinterpret_cast<uintptr_t>(stack);
+  if ((stackaddr % 16 != 0) || ((stackaddr + stacksize) % 16 != 0))
+    return EINVAL;
+  attr->__stack = stack;
+  attr->__stacksize = stacksize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_setstack.h b/libc/src/pthread/pthread_attr_setstack.h
new file mode 100644
index 000000000000..44ee2c9e35de
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setstack.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_setstack ---------*- 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_PTHREAD_PTHREAD_ATTR_SETSTACK_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETSTACK_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_setstack(pthread_attr_t *attr, void *stack, size_t stacksize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETSTACK_H
diff --git a/libc/src/pthread/pthread_attr_setstacksize.cpp b/libc/src/pthread/pthread_attr_setstacksize.cpp
new file mode 100644
index 000000000000..adf568db46fa
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setstacksize.cpp
@@ -0,0 +1,28 @@
+//===-- Implementation of the pthread_attr_setstacksize -----------------===//
+//
+// 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 "pthread_attr_setstacksize.h"
+
+#include "src/__support/common.h"
+
+#include <errno.h>
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+LLVM_LIBC_FUNCTION(int, pthread_attr_setstacksize,
+                   (pthread_attr_t *__restrict attr, size_t stacksize)) {
+  if (stacksize < PTHREAD_STACK_MIN)
+    return EINVAL;
+  attr->__stack = nullptr;
+  attr->__stacksize = stacksize;
+  return 0;
+}
+
+} // namespace __llvm_libc
diff --git a/libc/src/pthread/pthread_attr_setstacksize.h b/libc/src/pthread/pthread_attr_setstacksize.h
new file mode 100644
index 000000000000..40ee5c07d44e
--- /dev/null
+++ b/libc/src/pthread/pthread_attr_setstacksize.h
@@ -0,0 +1,20 @@
+//===-- Implementation header for pthread_attr_setstacksize -----*- 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_PTHREAD_PTHREAD_ATTR_SETSTACKSIZE_H
+#define LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETSTACKSIZE_H
+
+#include <pthread.h>
+
+namespace __llvm_libc {
+
+int pthread_attr_setstacksize(pthread_attr_t *attr, size_t stacksize);
+
+} // namespace __llvm_libc
+
+#endif // LLVM_LIBC_SRC_PTHREAD_PTHREAD_ATTR_SETSTACKSIZE_H
diff --git a/libc/test/src/pthread/CMakeLists.txt b/libc/test/src/pthread/CMakeLists.txt
index 552c7feca2d6..db0516cecc4f 100644
--- a/libc/test/src/pthread/CMakeLists.txt
+++ b/libc/test/src/pthread/CMakeLists.txt
@@ -1,6 +1,27 @@
 add_libc_testsuite(libc_pthread_unittests)
 
 add_libc_unittest(
+  pthread_attr_test
+  SUITE
+    libc_pthread_unittests
+  SRCS
+    pthread_attr_test.cpp
+  DEPENDS
+    libc.include.errno
+    libc.include.pthread
+    libc.src.pthread.pthread_attr_destroy
+    libc.src.pthread.pthread_attr_init
+    libc.src.pthread.pthread_attr_getdetachstate
+    libc.src.pthread.pthread_attr_getguardsize
+    libc.src.pthread.pthread_attr_getstacksize
+    libc.src.pthread.pthread_attr_getstack
+    libc.src.pthread.pthread_attr_setdetachstate
+    libc.src.pthread.pthread_attr_setguardsize
+    libc.src.pthread.pthread_attr_setstacksize
+    libc.src.pthread.pthread_attr_setstack
+)
+
+add_libc_unittest(
   pthread_mutexattr_test
   SUITE
     libc_pthread_unittests
diff --git a/libc/test/src/pthread/pthread_attr_test.cpp b/libc/test/src/pthread/pthread_attr_test.cpp
new file mode 100644
index 000000000000..fe002db966dc
--- /dev/null
+++ b/libc/test/src/pthread/pthread_attr_test.cpp
@@ -0,0 +1,113 @@
+//===-- Unittests for pthread_attr_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
+//
+//===----------------------------------------------------------------------===//
+
+#include "src/pthread/pthread_attr_destroy.h"
+#include "src/pthread/pthread_attr_getdetachstate.h"
+#include "src/pthread/pthread_attr_getguardsize.h"
+#include "src/pthread/pthread_attr_getstack.h"
+#include "src/pthread/pthread_attr_getstacksize.h"
+#include "src/pthread/pthread_attr_init.h"
+#include "src/pthread/pthread_attr_setdetachstate.h"
+#include "src/pthread/pthread_attr_setguardsize.h"
+#include "src/pthread/pthread_attr_setstack.h"
+#include "src/pthread/pthread_attr_setstacksize.h"
+
+#include "utils/UnitTest/Test.h"
+
+#include <errno.h>
+#include <linux/param.h> // For EXEC_PAGESIZE.
+#include <pthread.h>
+
+TEST(LlvmLibcPThreadAttrTest, InitAndDestroy) {
+  pthread_attr_t attr;
+  ASSERT_EQ(__llvm_libc::pthread_attr_init(&attr), 0);
+
+  int detachstate;
+  ASSERT_EQ(__llvm_libc::pthread_attr_getdetachstate(&attr, &detachstate), 0);
+  ASSERT_EQ(detachstate, int(PTHREAD_CREATE_JOINABLE));
+
+  size_t guardsize;
+  ASSERT_EQ(__llvm_libc::pthread_attr_getguardsize(&attr, &guardsize), 0);
+  ASSERT_EQ(guardsize, size_t(EXEC_PAGESIZE));
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_destroy(&attr), 0);
+}
+
+TEST(LlvmLibcPThreadattrTest, SetAndGetDetachState) {
+  pthread_attr_t attr;
+  ASSERT_EQ(__llvm_libc::pthread_attr_init(&attr), 0);
+
+  int detachstate;
+  __llvm_libc::pthread_attr_getdetachstate(&attr, &detachstate);
+  ASSERT_EQ(detachstate, int(PTHREAD_CREATE_JOINABLE));
+  ASSERT_EQ(
+      __llvm_libc::pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED),
+      0);
+  ASSERT_EQ(__llvm_libc::pthread_attr_getdetachstate(&attr, &detachstate), 0);
+  ASSERT_EQ(detachstate, int(PTHREAD_CREATE_DETACHED));
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_setdetachstate(&attr, 0xBAD), EINVAL);
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_destroy(&attr), 0);
+}
+
+TEST(LlvmLibcPThreadattrTest, SetAndGetGuardSize) {
+  pthread_attr_t attr;
+  ASSERT_EQ(__llvm_libc::pthread_attr_init(&attr), 0);
+
+  size_t guardsize;
+  ASSERT_EQ(__llvm_libc::pthread_attr_getguardsize(&attr, &guardsize), 0);
+  ASSERT_EQ(guardsize, size_t(EXEC_PAGESIZE));
+  ASSERT_EQ(__llvm_libc::pthread_attr_setguardsize(&attr, 2 * EXEC_PAGESIZE),
+            0);
+  ASSERT_EQ(__llvm_libc::pthread_attr_getguardsize(&attr, &guardsize), 0);
+  ASSERT_EQ(guardsize, size_t(2 * EXEC_PAGESIZE));
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_setguardsize(&attr, EXEC_PAGESIZE / 2),
+            EINVAL);
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_destroy(&attr), 0);
+}
+
+TEST(LlvmLibcPThreadattrTest, SetAndGetStackSize) {
+  pthread_attr_t attr;
+  ASSERT_EQ(__llvm_libc::pthread_attr_init(&attr), 0);
+
+  size_t stacksize;
+  ASSERT_EQ(
+      __llvm_libc::pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN << 2), 0);
+  ASSERT_EQ(__llvm_libc::pthread_attr_getstacksize(&attr, &stacksize), 0);
+  ASSERT_EQ(stacksize, size_t(PTHREAD_STACK_MIN << 2));
+
+  ASSERT_EQ(
+      __llvm_libc::pthread_attr_setstacksize(&attr, PTHREAD_STACK_MIN / 2),
+      EINVAL);
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_destroy(&attr), 0);
+}
+
+TEST(LlvmLibcPThreadattrTest, SetAndGetStack) {
+  pthread_attr_t attr;
+  ASSERT_EQ(__llvm_libc::pthread_attr_init(&attr), 0);
+
+  void *stack;
+  size_t stacksize;
+  ASSERT_EQ(
+      __llvm_libc::pthread_attr_setstack(&attr, 0, PTHREAD_STACK_MIN << 2), 0);
+  ASSERT_EQ(__llvm_libc::pthread_attr_getstack(&attr, &stack, &stacksize), 0);
+  ASSERT_EQ(stacksize, size_t(PTHREAD_STACK_MIN << 2));
+  ASSERT_EQ(reinterpret_cast<uintptr_t>(stack), uintptr_t(0));
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_setstack(
+                &attr, reinterpret_cast<void *>(1), PTHREAD_STACK_MIN << 2),
+            EINVAL);
+  ASSERT_EQ(__llvm_libc::pthread_attr_setstack(&attr, 0, PTHREAD_STACK_MIN / 2),
+            EINVAL);
+
+  ASSERT_EQ(__llvm_libc::pthread_attr_destroy(&attr), 0);
+}