[libc-commits] [libc] [libc]: add `dlfcn.h` headers (PR #97772)

[Izaak Schroeder via libc-commits]

https://github.com/izaakschroeder created https://github.com/llvm/llvm-project/pull/97772

Does what it says on the box.

>From 0dd0cdde271da42a2ffb3877ca3c2723f2ce00b7 Mon Sep 17 00:00:00 2001
From: Izaak Schroeder <izaak.schroeder at gmail.com>
Date: Thu, 4 Jul 2024 16:07:36 -0700
Subject: [PATCH] [libc]: add `dlfcn.h` headers

---
 libc/config/linux/aarch64/headers.txt        |  1 +
 libc/config/linux/x86_64/headers.txt         |  1 +
 libc/include/CMakeLists.txt                  |  9 +++++
 libc/include/dlfcn.h.def                     | 17 ++++++++++
 libc/include/llvm-libc-macros/CMakeLists.txt |  6 ++++
 libc/include/llvm-libc-macros/dlfcn-macros.h | 23 +++++++++++++
 libc/spec/posix.td                           | 35 ++++++++++++++++++++
 7 files changed, 92 insertions(+)
 create mode 100644 libc/include/dlfcn.h.def
 create mode 100644 libc/include/llvm-libc-macros/dlfcn-macros.h

diff --git a/libc/config/linux/aarch64/headers.txt b/libc/config/linux/aarch64/headers.txt
index 7d25877cefcc8..8f898f0150905 100644
--- a/libc/config/linux/aarch64/headers.txt
+++ b/libc/config/linux/aarch64/headers.txt
@@ -1,6 +1,7 @@
 set(TARGET_PUBLIC_HEADERS
     libc.include.assert
     libc.include.ctype
+    libc.include.dlfcn
     libc.include.errno
     libc.include.features
     libc.include.fenv
diff --git a/libc/config/linux/x86_64/headers.txt b/libc/config/linux/x86_64/headers.txt
index 44d640b75e2bf..df276894246c4 100644
--- a/libc/config/linux/x86_64/headers.txt
+++ b/libc/config/linux/x86_64/headers.txt
@@ -2,6 +2,7 @@ set(TARGET_PUBLIC_HEADERS
     libc.include.assert
     libc.include.ctype
     libc.include.dirent
+    libc.include.dlfcn
     libc.include.errno
     libc.include.fcntl
     libc.include.features
diff --git a/libc/include/CMakeLists.txt b/libc/include/CMakeLists.txt
index 3ab7817d8568b..f8ef35078a8c4 100644
--- a/libc/include/CMakeLists.txt
+++ b/libc/include/CMakeLists.txt
@@ -51,6 +51,15 @@ add_gen_header(
     .llvm_libc_common_h
 )
 
+add_gen_header(
+  dlfcn
+  DEF_FILE dlfcn.h.def
+  GEN_HDR dlfcn.h
+  DEPENDS
+    .llvm-libc-macros.dlfcn_macros
+    .llvm_libc_common_h
+)
+
 add_gen_header(
   features
   DEF_FILE features.h.def
diff --git a/libc/include/dlfcn.h.def b/libc/include/dlfcn.h.def
new file mode 100644
index 0000000000000..31395871c6b97
--- /dev/null
+++ b/libc/include/dlfcn.h.def
@@ -0,0 +1,17 @@
+//===-- C standard library header dlfcn.h ---------------------------------===//
+//
+// 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_DLFCN_H
+#define LLVM_LIBC_DLFCN_H
+
+#include "__llvm-libc-common.h"
+#include "llvm-libc-macros/dlfcn-macros.h"
+
+%%public_api()
+
+#endif // LLVM_LIBC_DLFCN_H
diff --git a/libc/include/llvm-libc-macros/CMakeLists.txt b/libc/include/llvm-libc-macros/CMakeLists.txt
index f6af11abd4dd7..5bf573e4e98df 100644
--- a/libc/include/llvm-libc-macros/CMakeLists.txt
+++ b/libc/include/llvm-libc-macros/CMakeLists.txt
@@ -277,3 +277,9 @@ add_macro_header(
   HDR
     stdckdint-macros.h
 )
+
+add_macro_header(
+  dlfcn_macros
+  HDR
+    dlfcn-macros.h
+)
\ No newline at end of file
diff --git a/libc/include/llvm-libc-macros/dlfcn-macros.h b/libc/include/llvm-libc-macros/dlfcn-macros.h
new file mode 100644
index 0000000000000..dcd202b9ab435
--- /dev/null
+++ b/libc/include/llvm-libc-macros/dlfcn-macros.h
@@ -0,0 +1,23 @@
+//===-- Definition of macros from dlfcn.h ---------------------------------===//
+//
+// 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_MACROS_DLFCN_MACROS_H
+#define LLVM_LIBC_MACROS_DLFCN_MACROS_H
+
+#define RTLD_LAZY 0x00001
+#define RTLD_NOW 0x00002
+#define RTLD_GLOBAL 0x00100
+#define RTLD_LOCAL 0
+
+// Non-standard stuff here
+#define RTLD_BINDING_MASK 0x3
+#define RTLD_NOLOAD 0x00004
+#define RTLD_DEEPBIND 0x00008
+#define RTLD_NODELETE 0x01000
+
+#endif // LLVM_LIBC_MACROS_DLFCN_MACROS_H
diff --git a/libc/spec/posix.td b/libc/spec/posix.td
index d14047548e104..1878b1ee2ae41 100644
--- a/libc/spec/posix.td
+++ b/libc/spec/posix.td
@@ -222,6 +222,40 @@ def POSIX : StandardSpec<"POSIX"> {
       []  // Functions
   >;
 
+  HeaderSpec DlFcn = HeaderSpec<
+    "dlfcn.h",
+    [
+      Macro<"RTLD_LAZY">,
+      Macro<"RTLD_NOW">,
+      Macro<"RTLD_GLOBAL">,
+      Macro<"RTLD_LOCAL">,
+    ],
+    [],  // Types
+    [], // Enumerations
+    [
+      FunctionSpec<
+          "dlclose",
+          RetValSpec<IntType>,
+          [ArgSpec<VoidPtr>]
+      >,
+      FunctionSpec<
+          "dlerror",
+          RetValSpec<CharPtr>,
+          []
+      >,
+      FunctionSpec<
+          "dlopen",
+          RetValSpec<VoidPtr>,
+          [ArgSpec<ConstCharPtr>, ArgSpec<IntType>]
+      >,
+      FunctionSpec<
+          "dlsym",
+          RetValSpec<VoidPtr>,
+          [ArgSpec<VoidRestrictedPtr>, ArgSpec<ConstCharRestrictedPtr>]
+      >,
+    ]
+  >;
+
   HeaderSpec FCntl = HeaderSpec<
     "fcntl.h",
     [], // Macros
@@ -1690,6 +1724,7 @@ def POSIX : StandardSpec<"POSIX"> {
     ArpaInet,
     CType,
     Dirent,
+    DlFcn,
     Errno,
     FCntl,
     PThread,