Kernel+LibC: Turn errno codes into a strongly typed enum

..and allow implicit creation of KResult and KResultOr from ErrnoCode.
This means that kernel functions that return those types can finally
do "return EINVAL;" and it will just work.

There's a handful of functions that still deal with signed integers
that should be converted to return KResults.

1 files changed, 5 insertions, 5 deletions

diff --git a/Kernel/FileSystem/InodeFile.cpp b/Kernel/FileSystem/InodeFile.cpp
index 58a3f2459e..3cade1cf5f 100644
--- a/Kernel/FileSystem/InodeFile.cpp
+++ b/Kernel/FileSystem/InodeFile.cpp
@@ -52,7 +52,7 @@ KResultOr<size_t> InodeFile::read(FileDescription& description, size_t offset, U
         evaluate_block_conditions();
     }
     if (nread < 0)
-        return KResult(nread);
+        return KResult((ErrnoCode)-nread);
     return nread;
 }
 
@@ -65,7 +65,7 @@ KResultOr<size_t> InodeFile::write(FileDescription& description, size_t offset,
         evaluate_block_conditions();
     }
     if (nwritten < 0)
-        return KResult(nwritten);
+        return KResult((ErrnoCode)-nwritten);
     return nwritten;
 }
 
@@ -78,7 +78,7 @@ KResultOr<Region*> InodeFile::mmap(Process& process, FileDescription& descriptio
     else
         vmobject = PrivateInodeVMObject::create_with_inode(inode());
     if (!vmobject)
-        return KResult(-ENOMEM);
+        return ENOMEM;
     return process.allocate_region_with_vmobject(preferred_vaddr, size, *vmobject, offset, description.absolute_path(), prot, shared);
 }
 
@@ -95,8 +95,8 @@ KResult InodeFile::truncate(u64 size)
     if (truncate_result.is_error())
         return truncate_result;
     int mtime_result = m_inode->set_mtime(kgettimeofday().tv_sec);
-    if (mtime_result != 0)
-        return KResult(mtime_result);
+    if (mtime_result < 0)
+        return KResult((ErrnoCode)-mtime_result);
     return KSuccess;
 }