[libc][POSIX] implement fseeko, ftello #86928

Sh0g0-1758 · 2024-03-28T10:11:00Z

Fixes: #85287

Ran Formatter

Sh0g0-1758 · 2024-03-28T10:11:24Z

@nickdesaulniers

llvmbot · 2024-03-28T10:11:28Z

@llvm/pr-subscribers-libc

Author: Shourya Goel (Sh0g0-1758)

Changes

Fixes: #85287

Full diff: https://github.com/llvm/llvm-project/pull/86928.diff

9 Files Affected:

(modified) libc/config/linux/x86_64/entrypoints.txt (+2)
(modified) libc/src/stdio/CMakeLists.txt (+2)
(added) libc/src/stdio/fseeko.h (+20)
(added) libc/src/stdio/ftello.h (+20)
(modified) libc/src/stdio/generic/CMakeLists.txt (+26)
(added) libc/src/stdio/generic/fseeko.cpp (+27)
(added) libc/src/stdio/generic/ftello.cpp (+26)
(modified) libc/test/src/stdio/CMakeLists.txt (+2)
(modified) libc/test/src/stdio/ftell_test.cpp (+9)

diff --git a/libc/config/linux/x86_64/entrypoints.txt b/libc/config/linux/x86_64/entrypoints.txt
index 5b428e51aee620..a4d0da5e043d4f 100644
--- a/libc/config/linux/x86_64/entrypoints.txt
+++ b/libc/config/linux/x86_64/entrypoints.txt
@@ -681,6 +681,8 @@ if(LLVM_LIBC_FULL_BUILD)
     libc.src.stdio.fread_unlocked
     libc.src.stdio.fseek
     libc.src.stdio.ftell
+    libc.src.stdio.fseeko
+    libc.src.stdio.ftello
     libc.src.stdio.funlockfile
     libc.src.stdio.fwrite
     libc.src.stdio.fwrite_unlocked
diff --git a/libc/src/stdio/CMakeLists.txt b/libc/src/stdio/CMakeLists.txt
index 11e15c91735188..1056f38fc7513a 100644
--- a/libc/src/stdio/CMakeLists.txt
+++ b/libc/src/stdio/CMakeLists.txt
@@ -270,6 +270,8 @@ add_stdio_entrypoint_object(ferror)
 add_stdio_entrypoint_object(ferror_unlocked)
 add_stdio_entrypoint_object(fseek)
 add_stdio_entrypoint_object(ftell)
+add_stdio_entrypoint_object(fseeko)
+add_stdio_entrypoint_object(ftello)
 add_stdio_entrypoint_object(fflush)
 add_stdio_entrypoint_object(clearerr)
 add_stdio_entrypoint_object(clearerr_unlocked)
diff --git a/libc/src/stdio/fseeko.h b/libc/src/stdio/fseeko.h
new file mode 100644
index 00000000000000..77fb41215c318f
--- /dev/null
+++ b/libc/src/stdio/fseeko.h
@@ -0,0 +1,20 @@
+//===-- Implementation header of fseeko -------------------------*- 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_STDIO_FSEEKO_H
+#define LLVM_LIBC_SRC_STDIO_FSEEKO_H
+
+#include <stdio.h>
+
+namespace LIBC_NAMESPACE {
+
+int fseeko(::FILE *stream, off_t offset, int whence);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDIO_FSEEKO_H
diff --git a/libc/src/stdio/ftello.h b/libc/src/stdio/ftello.h
new file mode 100644
index 00000000000000..5ab17f9244a5ad
--- /dev/null
+++ b/libc/src/stdio/ftello.h
@@ -0,0 +1,20 @@
+//===-- Implementation header of ftello -------------------------*- 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_STDIO_FTELLO_H
+#define LLVM_LIBC_SRC_STDIO_FTELLO_H
+
+#include <stdio.h>
+
+namespace LIBC_NAMESPACE {
+
+off_t ftello(::FILE *f);
+
+} // namespace LIBC_NAMESPACE
+
+#endif // LLVM_LIBC_SRC_STDIO_FTELLO_H
diff --git a/libc/src/stdio/generic/CMakeLists.txt b/libc/src/stdio/generic/CMakeLists.txt
index 0aa213caba7b8a..4b04c2e6df6022 100644
--- a/libc/src/stdio/generic/CMakeLists.txt
+++ b/libc/src/stdio/generic/CMakeLists.txt
@@ -121,6 +121,32 @@ add_entrypoint_object(
     libc.src.__support.File.platform_file
 )
 
+add_entrypoint_object(
+  fseeko
+  SRCS
+    fseeko.cpp
+  HDRS
+    ../fseeko.h
+  DEPENDS
+    libc.src.errno.errno
+    libc.include.stdio
+    libc.src.__support.File.file
+    libc.src.__support.File.platform_file
+)
+
+add_entrypoint_object(
+  ftello
+  SRCS
+    ftello.cpp
+  HDRS
+    ../ftello.h
+  DEPENDS
+    libc.src.errno.errno
+    libc.include.stdio
+    libc.src.__support.File.file
+    libc.src.__support.File.platform_file
+)
+
 add_entrypoint_object(
   fopen
   SRCS
diff --git a/libc/src/stdio/generic/fseeko.cpp b/libc/src/stdio/generic/fseeko.cpp
new file mode 100644
index 00000000000000..aa581d9f06ea8c
--- /dev/null
+++ b/libc/src/stdio/generic/fseeko.cpp
@@ -0,0 +1,27 @@
+//===-- Implementation of fseeko ------------------------------------------===//
+//
+// 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/stdio/fseeko.h"
+#include "src/__support/File/file.h"
+
+#include "src/errno/libc_errno.h"
+#include <stdio.h>
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(int, fseeko, (::FILE * stream, off_t offset, int whence)) {
+  auto result =
+      reinterpret_cast<LIBC_NAMESPACE::File *>(stream)->seek(offset, whence);
+  if (!result.has_value()) {
+    libc_errno = result.error();
+    return -1;
+  }
+  return 0;
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/src/stdio/generic/ftello.cpp b/libc/src/stdio/generic/ftello.cpp
new file mode 100644
index 00000000000000..50d222e45249fa
--- /dev/null
+++ b/libc/src/stdio/generic/ftello.cpp
@@ -0,0 +1,26 @@
+//===-- Implementation of ftello ------------------------------------------===//
+//
+// 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/stdio/ftello.h"
+#include "src/__support/File/file.h"
+
+#include "src/errno/libc_errno.h"
+#include <stdio.h>
+
+namespace LIBC_NAMESPACE {
+
+LLVM_LIBC_FUNCTION(off_t, ftello, (::FILE * stream)) {
+  auto result = reinterpret_cast<LIBC_NAMESPACE::File *>(stream)->tell();
+  if (!result.has_value()) {
+    libc_errno = result.error();
+    return -1;
+  }
+  return result.value();
+}
+
+} // namespace LIBC_NAMESPACE
diff --git a/libc/test/src/stdio/CMakeLists.txt b/libc/test/src/stdio/CMakeLists.txt
index 4c38e8aba7d7f2..03c43eaefebe5e 100644
--- a/libc/test/src/stdio/CMakeLists.txt
+++ b/libc/test/src/stdio/CMakeLists.txt
@@ -442,6 +442,8 @@ add_libc_test(
     libc.src.stdio.fread
     libc.src.stdio.fseek
     libc.src.stdio.ftell
+    libc.src.stdio.fseeko
+    libc.src.stdio.ftello
     libc.src.stdio.fwrite
     libc.src.stdio.setvbuf
 )
diff --git a/libc/test/src/stdio/ftell_test.cpp b/libc/test/src/stdio/ftell_test.cpp
index 61b626f53cd26e..68a969ed0c30dd 100644
--- a/libc/test/src/stdio/ftell_test.cpp
+++ b/libc/test/src/stdio/ftell_test.cpp
@@ -10,7 +10,9 @@
 #include "src/stdio/fopen.h"
 #include "src/stdio/fread.h"
 #include "src/stdio/fseek.h"
+#include "src/stdio/fseeko.h"
 #include "src/stdio/ftell.h"
+#include "src/stdio/ftello.h"
 #include "src/stdio/fwrite.h"
 #include "src/stdio/setvbuf.h"
 #include "test/UnitTest/Test.h"
@@ -37,6 +39,13 @@ class LlvmLibcFTellTest : public LIBC_NAMESPACE::testing::Test {
     // still return the correct effective offset.
     ASSERT_EQ(size_t(LIBC_NAMESPACE::ftell(file)), WRITE_SIZE);
 
+    off_t offseto = 42;
+    ASSERT_EQ(0, LIBC_NAMESPACE::fseeko(file, offseto, SEEK_SET));
+    ASSERT_EQ(LIBC_NAMESPACE::ftello(file), offseto);
+    ASSERT_EQ(0, LIBC_NAMESPACE::fseeko(file, -offseto, SEEK_END));
+    ASSERT_EQ(size_t(LIBC_NAMESPACE::ftello(file)),
+              size_t(WRITE_SIZE - offseto));
+
     long offset = 5;
     ASSERT_EQ(0, LIBC_NAMESPACE::fseek(file, offset, SEEK_SET));
     ASSERT_EQ(LIBC_NAMESPACE::ftell(file), offset);

Sh0g0-1758 · 2024-03-28T19:25:59Z

@intue, pinging for comments on this pr.

libc/src/stdio/generic/ftello.cpp

libc/src/stdio/generic/fseeko.cpp

Sh0g0-1758 · 2024-03-30T19:10:07Z

@nickdesaulniers, are any other changes required?

nickdesaulniers · 2024-04-01T17:02:50Z

No, feel free to merge. Or do you need one of us to do so?

Sh0g0-1758 · 2024-04-01T17:08:05Z

I don't have write access yet. Would be needing you to land for me.

nickdesaulniers · 2024-04-01T17:09:44Z

Done, thanks again for the patch!

Sh0g0-1758 · 2024-04-01T17:16:21Z

@nickdesaulniers, the patch is failing in post submit. I think we need to change off_t -> off64_t?

Fixes llvm#86928

nickdesaulniers · 2024-04-01T17:22:42Z

#87266

Fixes #86928

Use a seek offset that fits within the file size. This was missed in presubmit because the FILE based stdio tests aren't run in overlay mode; fullbuild is not tested in presubmit. WRITE_SIZE == 11, so using a value of 42 for offseto would cause the expression `WRITE_SIZE - offseto` to evaluate to -31 as an unsigned 64b integer (18446744073709551585ULL). Fixes llvm#86928

Use a seek offset that fits within the file size. This was missed in presubmit because the FILE based stdio tests aren't run in overlay mode; fullbuild is not tested in presubmit. WRITE_SIZE == 11, so using a value of 42 for offseto would cause the expression `WRITE_SIZE - offseto` to evaluate to -31 as an unsigned 64b integer (18446744073709551585ULL). Fixes #86928

Added implementation

10b8074

Ran Formatter

llvmbot added the libc label Mar 28, 2024

lntue requested review from michaelrj-google, nickdesaulniers and SchrodingerZhu March 28, 2024 19:35

nickdesaulniers reviewed Mar 28, 2024

View reviewed changes

libc/src/stdio/generic/ftello.cpp Outdated Show resolved Hide resolved

Update includes

64ba543

nickdesaulniers reviewed Mar 28, 2024

View reviewed changes

libc/src/stdio/generic/fseeko.cpp Show resolved Hide resolved

nickdesaulniers reviewed Mar 28, 2024

View reviewed changes

libc/src/stdio/generic/fseeko.cpp Show resolved Hide resolved

nickdesaulniers approved these changes Mar 29, 2024

View reviewed changes

nickdesaulniers merged commit 55b7403 into llvm:main Apr 1, 2024

nickdesaulniers mentioned this pull request Apr 1, 2024

[libc] fixup missing include for fullbuild #87266

Merged

nickdesaulniers added a commit to nickdesaulniers/llvm-project that referenced this pull request Apr 1, 2024

[libc] fixup missing include for fullbuild

7ed8424

Fixes llvm#86928

nickdesaulniers added a commit that referenced this pull request Apr 1, 2024

[libc] fixup missing include for fullbuild (#87266)

2cfd7d4

Fixes #86928

nickdesaulniers mentioned this pull request Apr 1, 2024

[libc] fixup ftello test #87282

Merged

Provide feedback

Saved searches

Use saved searches to filter your results more quickly

Uh oh!

[libc][POSIX] implement fseeko, ftello #86928

[libc][POSIX] implement fseeko, ftello #86928

Uh oh!

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

llvmbot commented Mar 28, 2024

Uh oh!

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Sh0g0-1758 commented Mar 30, 2024

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Sh0g0-1758 commented Apr 1, 2024

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Sh0g0-1758 commented Apr 1, 2024 •

edited

Loading

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Uh oh!

[libc][POSIX] implement fseeko, ftello #86928

[libc][POSIX] implement fseeko, ftello #86928

Uh oh!

Conversation

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

llvmbot commented Mar 28, 2024

Uh oh!

Sh0g0-1758 commented Mar 28, 2024

Uh oh!

Uh oh!

Uh oh!

Uh oh!

Sh0g0-1758 commented Mar 30, 2024

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Sh0g0-1758 commented Apr 1, 2024

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Sh0g0-1758 commented Apr 1, 2024 • edited Loading Uh oh! There was an error while loading. Please reload this page.

Uh oh!

Uh oh!

nickdesaulniers commented Apr 1, 2024

Uh oh!

Uh oh!

Sh0g0-1758 commented Apr 1, 2024 •

edited

Loading