From 371c51f934acc4496645666633224e2371b53f5d Mon Sep 17 00:00:00 2001
From: Tim Schumacher <timschumi@gmx.de>
Date: Sun, 29 Jan 2023 13:49:42 +0100
Subject: [PATCH] AK: Make `SeekableStream::truncate()` take a `size_t`

Similar to the return values earlier, a signed value doesn't really make
sense here. Relying on the much more standard `size_t` makes it easier
to use Stream in all contexts.
---
 AK/BufferedStream.h                   | 2 +-
 AK/MemoryStream.cpp                   | 2 +-
 AK/MemoryStream.h                     | 2 +-
 AK/Stream.h                           | 2 +-
 Userland/Libraries/LibCore/Stream.cpp | 5 ++++-
 Userland/Libraries/LibCore/Stream.h   | 2 +-
 6 files changed, 9 insertions(+), 6 deletions(-)

diff --git a/AK/BufferedStream.h b/AK/BufferedStream.h
index cb3c3d59ec0..8ff0c9b8897 100644
--- a/AK/BufferedStream.h
+++ b/AK/BufferedStream.h
@@ -295,7 +295,7 @@ public:
 
         return result;
     }
-    virtual ErrorOr<void> truncate(off_t length) override
+    virtual ErrorOr<void> truncate(size_t length) override
     {
         return m_helper.stream().truncate(length);
     }
diff --git a/AK/MemoryStream.cpp b/AK/MemoryStream.cpp
index e4b3bc94f36..d4c9659b3a5 100644
--- a/AK/MemoryStream.cpp
+++ b/AK/MemoryStream.cpp
@@ -48,7 +48,7 @@ void FixedMemoryStream::close()
     // FIXME: It doesn't make sense to close a memory stream. Therefore, we don't do anything here. Is that fine?
 }
 
-ErrorOr<void> FixedMemoryStream::truncate(off_t)
+ErrorOr<void> FixedMemoryStream::truncate(size_t)
 {
     return Error::from_errno(EBADF);
 }
diff --git a/AK/MemoryStream.h b/AK/MemoryStream.h
index c19de82cffa..b81310b0634 100644
--- a/AK/MemoryStream.h
+++ b/AK/MemoryStream.h
@@ -22,7 +22,7 @@ public:
     virtual bool is_eof() const override;
     virtual bool is_open() const override;
     virtual void close() override;
-    virtual ErrorOr<void> truncate(off_t) override;
+    virtual ErrorOr<void> truncate(size_t) override;
     virtual ErrorOr<Bytes> read(Bytes bytes) override;
 
     virtual ErrorOr<size_t> seek(i64 offset, SeekMode seek_mode = SeekMode::SetPosition) override;
diff --git a/AK/Stream.h b/AK/Stream.h
index 9a039ea8e6c..d01ae9ddb33 100644
--- a/AK/Stream.h
+++ b/AK/Stream.h
@@ -120,7 +120,7 @@ public:
     virtual ErrorOr<size_t> size();
     /// Shrinks or extends the stream to the given size. Returns an errno in
     /// the case of an error.
-    virtual ErrorOr<void> truncate(off_t length) = 0;
+    virtual ErrorOr<void> truncate(size_t length) = 0;
     /// Seeks until after the given amount of bytes to be discarded instead of
     /// reading and discarding everything manually;
     virtual ErrorOr<void> discard(size_t discarded_bytes) override;
diff --git a/Userland/Libraries/LibCore/Stream.cpp b/Userland/Libraries/LibCore/Stream.cpp
index 4d68880315d..dc6d744a450 100644
--- a/Userland/Libraries/LibCore/Stream.cpp
+++ b/Userland/Libraries/LibCore/Stream.cpp
@@ -184,8 +184,11 @@ ErrorOr<size_t> File::seek(i64 offset, SeekMode mode)
     return seek_result;
 }
 
-ErrorOr<void> File::truncate(off_t length)
+ErrorOr<void> File::truncate(size_t length)
 {
+    if (length > static_cast<size_t>(NumericLimits<off_t>::max()))
+        return Error::from_string_literal("Length is larger than the maximum supported length");
+
     return System::ftruncate(m_fd, length);
 }
 
diff --git a/Userland/Libraries/LibCore/Stream.h b/Userland/Libraries/LibCore/Stream.h
index 404600e602c..bc4df1775b0 100644
--- a/Userland/Libraries/LibCore/Stream.h
+++ b/Userland/Libraries/LibCore/Stream.h
@@ -169,7 +169,7 @@ public:
     virtual bool is_open() const override;
     virtual void close() override;
     virtual ErrorOr<size_t> seek(i64 offset, SeekMode) override;
-    virtual ErrorOr<void> truncate(off_t length) override;
+    virtual ErrorOr<void> truncate(size_t length) override;
 
     int leak_fd(Badge<::IPC::File>)
     {