[libc] Migrate from baremetal stdio.h to generic stdio.h

libc/config/baremetal/aarch64/entrypoints.txt

@@ -124,6 +124,8 @@ set(TARGET_LIBC_ENTRYPOINTS
 
     # stdio.h entrypoints
     libc.src.stdio.asprintf
+    libc.src.stdio.fopencookie
+    libc.src.stdio.fprintf
     libc.src.stdio.getchar
     libc.src.stdio.printf
     libc.src.stdio.putchar

libc/config/baremetal/arm/entrypoints.txt

@@ -124,6 +124,8 @@ set(TARGET_LIBC_ENTRYPOINTS
 
     # stdio.h entrypoints
     libc.src.stdio.asprintf
+    libc.src.stdio.fopencookie
+    libc.src.stdio.fprintf
     libc.src.stdio.getchar
     libc.src.stdio.printf
     libc.src.stdio.putchar

libc/config/baremetal/riscv/entrypoints.txt

@@ -124,6 +124,8 @@ set(TARGET_LIBC_ENTRYPOINTS
 
     # stdio.h entrypoints
     libc.src.stdio.asprintf
+    libc.src.stdio.fopencookie
+    libc.src.stdio.fprintf
     libc.src.stdio.getchar
     libc.src.stdio.printf
     libc.src.stdio.putchar

libc/src/__support/File/CMakeLists.txt

@@ -22,6 +22,18 @@ add_object_library(
     libc.src.__support.error_or
 )
 
+add_header_library(
+  cookie_file
+  HDRS
+    cookie_file.h
+  DEPENDS
+    .file
+    libc.hdr.errno_macros
+    libc.hdr.types.cookie_io_functions_t
+    libc.hdr.types.off_t
+    libc.src.__support.CPP.new
+)
+
 add_object_library(
   dir
   SRCS
@@ -41,7 +53,11 @@ endif()
 
 add_subdirectory(${LIBC_TARGET_OS})
 
-set(target_file libc.src.__support.File.${LIBC_TARGET_OS}.file)
+if(LIBC_TARGET_OS_IS_BAREMETAL)
+  set(target_file libc.src.__support.File.cookie_file)
+else()
+  set(target_file libc.src.__support.File.${LIBC_TARGET_OS}.file)
+endif()
 set(target_stdout libc.src.__support.File.${LIBC_TARGET_OS}.stdout)
 set(target_stderr libc.src.__support.File.${LIBC_TARGET_OS}.stderr)
 set(target_stdin libc.src.__support.File.${LIBC_TARGET_OS}.stdin)

libc/src/__support/File/baremetal/CMakeLists.txt

@@ -0,0 +1,32 @@
+add_object_library(
+  stdout
+  SRCS
+    stdout.cpp
+  DEPENDS
+    libc.hdr.stdio_macros
+    libc.src.__support.File.cookie_file
+    libc.src.__support.File.file
+    libc.src.__support.OSUtil.osutil
+)
+
+add_object_library(
+  stdin
+  SRCS
+    stdin.cpp
+  DEPENDS
+    libc.hdr.stdio_macros
+    libc.src.__support.File.cookie_file
+    libc.src.__support.File.file
+    libc.src.__support.OSUtil.osutil
+)
+
+add_object_library(
+  stderr
+  SRCS
+    stderr.cpp
+  DEPENDS
+    libc.hdr.stdio_macros
+    libc.src.__support.File.cookie_file
+    libc.src.__support.File.file
+    libc.src.__support.OSUtil.osutil
+)

libc/src/__support/File/baremetal/stderr.cpp

@@ -0,0 +1,34 @@
+//===--- Definition of baremetal stderr -----------------------------------===//
+//
+// 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 "hdr/stdio_macros.h"
+#include "src/__support/File/cookie_file.h"
+#include "src/__support/File/file.h"
+#include "src/__support/OSUtil/baremetal/io.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+cookie_io_functions_t io_func = {.read = nullptr,
+                                 .write = __llvm_libc_stdio_write,
+                                 .seek = nullptr,
+                                 .close = nullptr};
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wglobal-constructors"
+// Buffering is implementation defined. Therefore to save RAM, we use no
+// buffering
+static CookieFile StdErr(&__llvm_libc_stderr_cookie, io_func, nullptr, 0,
+                         _IONBF, File::mode_flags("w"));
+#pragma clang diagnostic pop
+File *stderr = &StdErr;
+
+} // namespace LIBC_NAMESPACE_DECL
+
+extern "C" {
+FILE *stderr = reinterpret_cast<FILE *>(&LIBC_NAMESPACE::StdErr);
+}

libc/src/__support/File/baremetal/stdin.cpp

@@ -0,0 +1,34 @@
+//===--- Definition of baremetal stdin ------------------------------------===//
+//
+// 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 "hdr/stdio_macros.h"
+#include "src/__support/File/cookie_file.h"
+#include "src/__support/File/file.h"
+#include "src/__support/OSUtil/baremetal/io.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+cookie_io_functions_t io_func = {.read = __llvm_libc_stdio_read,
+                                 .write = nullptr,
+                                 .seek = nullptr,
+                                 .close = nullptr};
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wglobal-constructors"
+// Buffering is implementation defined. Therefore to save RAM, we use no
+// buffering
+static CookieFile StdIn(&__llvm_libc_stdin_cookie, io_func, nullptr, 0, _IONBF,
+                        File::mode_flags("r"));
+#pragma clang diagnostic pop
+File *stdin = &StdIn;
+
+} // namespace LIBC_NAMESPACE_DECL
+
+extern "C" {
+FILE *stdin = reinterpret_cast<FILE *>(&LIBC_NAMESPACE::StdIn);
+}

libc/src/__support/File/baremetal/stdout.cpp

@@ -0,0 +1,34 @@
+//===--- Definition of baremetal stdout -----------------------------------===//
+//
+// 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 "hdr/stdio_macros.h"
+#include "src/__support/File/cookie_file.h"
+#include "src/__support/File/file.h"
+#include "src/__support/OSUtil/baremetal/io.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+cookie_io_functions_t io_func = {.read = nullptr,
+                                 .write = __llvm_libc_stdio_write,
+                                 .seek = nullptr,
+                                 .close = nullptr};
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wglobal-constructors"
+// Buffering is implementation defined. Therefore to save RAM, we use no
+// buffering
+static CookieFile StdOut(&__llvm_libc_stdout_cookie, io_func, nullptr, 0,
+                         _IONBF, File::mode_flags("w"));
+#pragma clang diagnostic pop
+File *stdout = &StdOut;
+
+} // namespace LIBC_NAMESPACE_DECL
+
+extern "C" {
+FILE *stdout = reinterpret_cast<FILE *>(&LIBC_NAMESPACE::StdOut);
+}

libc/src/__support/File/cookie_file.h

@@ -0,0 +1,75 @@
+//===--- A platform independent cookie file class -------------------------===//
+//
+// 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 "hdr/errno_macros.h"
+#include "hdr/types/cookie_io_functions_t.h"
+#include "hdr/types/off_t.h"
+#include "src/__support/CPP/new.h"
+#include "src/__support/File/file.h"
+#include "src/__support/macros/config.h"
+
+namespace LIBC_NAMESPACE_DECL {
+
+class CookieFile : public LIBC_NAMESPACE::File {
+  void *cookie;
+  cookie_io_functions_t ops;
+
+  static FileIOResult cookie_write(File *f, const void *data, size_t size);
+  static FileIOResult cookie_read(File *f, void *data, size_t size);
+  static ErrorOr<off_t> cookie_seek(File *f, off_t offset, int whence);
+  static int cookie_close(File *f);
+
+public:
+  CookieFile(void *c, cookie_io_functions_t cops, uint8_t *buffer,
+             size_t bufsize, int buffer_mode, File::ModeFlags mode)
+      : File(&cookie_write, &cookie_read, &CookieFile::cookie_seek,
+             &cookie_close, buffer, bufsize, buffer_mode,
+             true /* File owns buffer */, mode),
+        cookie(c), ops(cops) {}
+};
+
+FileIOResult CookieFile::cookie_write(File *f, const void *data, size_t size) {
+  auto cookie_file = reinterpret_cast<CookieFile *>(f);
+  if (cookie_file->ops.write == nullptr)
+    return 0;
+  return static_cast<size_t>(cookie_file->ops.write(
+      cookie_file->cookie, reinterpret_cast<const char *>(data), size));
+}
+
+FileIOResult CookieFile::cookie_read(File *f, void *data, size_t size) {
+  auto cookie_file = reinterpret_cast<CookieFile *>(f);
+  if (cookie_file->ops.read == nullptr)
+    return 0;
+  return static_cast<size_t>(cookie_file->ops.read(
+      cookie_file->cookie, reinterpret_cast<char *>(data), size));
+}
+
+ErrorOr<off_t> CookieFile::cookie_seek(File *f, off_t offset, int whence) {
+  auto cookie_file = reinterpret_cast<CookieFile *>(f);
+  if (cookie_file->ops.seek == nullptr) {
+    return Error(EINVAL);
+  }
+  off64_t offset64 = offset;
+  int result = cookie_file->ops.seek(cookie_file->cookie, &offset64, whence);
+  if (result == 0)
+    return offset64;
+  return -1;
+}
+
+int CookieFile::cookie_close(File *f) {
+  auto cookie_file = reinterpret_cast<CookieFile *>(f);
+  if (cookie_file->ops.close == nullptr)
+    return 0;
+  int retval = cookie_file->ops.close(cookie_file->cookie);
+  if (retval != 0)
+    return retval;
+  delete cookie_file;
+  return 0;
+}
+
+} // namespace LIBC_NAMESPACE_DECL

libc/src/__support/OSUtil/baremetal/io.cpp

@@ -13,45 +13,6 @@
 
 namespace LIBC_NAMESPACE_DECL {
 
-// These are intended to be provided by the vendor.
-//
-// The signature of these types and functions intentionally match `fopencookie`
-// which allows the following:
-//
-// ```
-// struct __llvm_libc_stdio_cookie { ... };
-// ...
-// struct __llvm_libc_stdio_cookie __llvm_libc_stdin_cookie;
-// cookie_io_functions_t stdin_func = { .read = __llvm_libc_stdio_read };
-// FILE *stdin = fopencookie(&__llvm_libc_stdin_cookie, "r", stdin_func);
-// ...
-// struct __llvm_libc_stdio_cookie __llvm_libc_stdout_cookie;
-// cookie_io_functions_t stdout_func = { .write = __llvm_libc_stdio_write };
-// FILE *stdout = fopencookie(&__llvm_libc_stdout_cookie, "w", stdout_func);
-// ...
-// struct __llvm_libc_stdio_cookie __llvm_libc_stderr_cookie;
-// cookie_io_functions_t stderr_func = { .write = __llvm_libc_stdio_write };
-// FILE *stderr = fopencookie(&__llvm_libc_stderr_cookie, "w", stderr_func);
-// ```
-//
-// At the same time, implementation of functions like `printf` and `scanf` can
-// use `__llvm_libc_stdio_read` and `__llvm_libc_stdio_write` directly to avoid
-// the extra indirection.
-//
-// All three symbols `__llvm_libc_stdin_cookie`, `__llvm_libc_stdout_cookie`,
-// and `__llvm_libc_stderr_cookie` must be provided, even if they don't point
-// at anything.
-
-struct __llvm_libc_stdio_cookie;
-
-extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stdin_cookie;
-extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stdout_cookie;
-extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stderr_cookie;
-
-extern "C" ssize_t __llvm_libc_stdio_read(void *cookie, char *buf, size_t size);
-extern "C" ssize_t __llvm_libc_stdio_write(void *cookie, const char *buf,
-                                           size_t size);
-
 ssize_t read_from_stdin(char *buf, size_t size) {
   return __llvm_libc_stdio_read(static_cast<void *>(&__llvm_libc_stdin_cookie),
                                 buf, size);

libc/src/__support/OSUtil/baremetal/io.h

@@ -14,8 +14,46 @@
 #include "src/__support/CPP/string_view.h"
 #include "src/__support/macros/config.h"
 
+// These are intended to be provided by the vendor.
+//
+// The signature of these types and functions intentionally match `fopencookie`
+// which allows the following:
+//
+// ```
+// struct __llvm_libc_stdio_cookie { ... };
+// ...
+// struct __llvm_libc_stdio_cookie __llvm_libc_stdin_cookie;
+// cookie_io_functions_t stdin_func = { .read = __llvm_libc_stdio_read };
+// FILE *stdin = fopencookie(&__llvm_libc_stdin_cookie, "r", stdin_func);
+// ...
+// struct __llvm_libc_stdio_cookie __llvm_libc_stdout_cookie;
+// cookie_io_functions_t stdout_func = { .write = __llvm_libc_stdio_write };
+// FILE *stdout = fopencookie(&__llvm_libc_stdout_cookie, "w", stdout_func);
+// ...
+// struct __llvm_libc_stdio_cookie __llvm_libc_stderr_cookie;
+// cookie_io_functions_t stderr_func = { .write = __llvm_libc_stdio_write };
+// FILE *stderr = fopencookie(&__llvm_libc_stderr_cookie, "w", stderr_func);
+// ```
+//
+// At the same time, implementation of functions like `printf` and `scanf` can
+// use `__llvm_libc_stdio_read` and `__llvm_libc_stdio_write` directly to avoid
+// the extra indirection.
+//
+// All three symbols `__llvm_libc_stdin_cookie`, `__llvm_libc_stdout_cookie`,
+// and `__llvm_libc_stderr_cookie` must be provided, even if they don't point
+// at anything.
 namespace LIBC_NAMESPACE_DECL {
 
+struct __llvm_libc_stdio_cookie;
+
+extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stdin_cookie;
+extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stdout_cookie;
+extern "C" struct __llvm_libc_stdio_cookie __llvm_libc_stderr_cookie;
+
+extern "C" ssize_t __llvm_libc_stdio_read(void *cookie, char *buf, size_t size);
+extern "C" ssize_t __llvm_libc_stdio_write(void *cookie, const char *buf,
+                                           size_t size);
+
 ssize_t read_from_stdin(char *buf, size_t size);
 void write_to_stderr(cpp::string_view msg);
 void write_to_stdout(cpp::string_view msg);

libc/src/stdio/CMakeLists.txt

@@ -63,6 +63,7 @@ add_entrypoint_object(
     libc.hdr.types.cookie_io_functions_t
     libc.hdr.types.FILE
     libc.src.__support.CPP.new
+    libc.src.__support.File.cookie_file
     libc.src.__support.File.file
 )