[TextAPI] TBD Reader/Writer

Add basic infrastructure for reading and writting TBD files (version 1 - 3).

The TextAPI library is not used by anything yet (besides the unit tests). Tool
support will be added in a separate commit.

The TBD format is currently documented in the implementation file (TextStub.cpp).

https://reviews.llvm.org/D53945

Update: This contains changes to fix issues discovered by the bots:
 - add parentheses to silence warnings.
 - rename variables
 - use PlatformType from BinaryFormat
 - Trying if switching from a vector to an array will appeas the bots.
 - Replace the tuple with a struct to work around an explicit constructor bug.
 - This fixes an issue where we were leaking the YAML document if there was a
   parsing error.

Updated the license information in all files.

llvm-svn: 356820

1 files changed, 113 insertions, 0 deletions

diff --git a/llvm/lib/TextAPI/MachO/PackedVersion.cpp b/llvm/lib/TextAPI/MachO/PackedVersion.cpp
new file mode 100644
index 00000000000..8405aba90ed
--- /dev/null
+++ b/llvm/lib/TextAPI/MachO/PackedVersion.cpp
@@ -0,0 +1,113 @@
+//===- PackedVersion.cpp --------------------------------------------------===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Implements the Mach-O packed version.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/TextAPI/MachO/PackedVersion.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
+#include "llvm/ADT/StringExtras.h"
+#include "llvm/Support/Format.h"
+#include "llvm/Support/raw_ostream.h"
+
+namespace llvm {
+namespace MachO {
+
+bool PackedVersion::parse32(StringRef Str) {
+  Version = 0;
+
+  if (Str.empty())
+    return false;
+
+  SmallVector<StringRef, 3> Parts;
+  SplitString(Str, Parts, ".");
+
+  if (Parts.size() > 3)
+    return false;
+
+  unsigned long long Num;
+  if (getAsUnsignedInteger(Parts[0], 10, Num))
+    return false;
+
+  if (Num > UINT16_MAX)
+    return false;
+
+  Version = Num << 16;
+
+  for (unsigned i = 1, ShiftNum = 8; i < Parts.size(); ++i, ShiftNum -= 8) {
+    if (getAsUnsignedInteger(Parts[i], 10, Num))
+      return false;
+
+    if (Num > UINT8_MAX)
+      return false;
+
+    Version |= (Num << ShiftNum);
+  }
+
+  return true;
+}
+
+std::pair<bool, bool> PackedVersion::parse64(StringRef Str) {
+  bool Truncated = false;
+  Version = 0;
+
+  if (Str.empty())
+    return std::make_pair(false, Truncated);
+
+  SmallVector<StringRef, 5> Parts;
+  SplitString(Str, Parts, ".");
+
+  if (Parts.size() > 5)
+    return std::make_pair(false, Truncated);
+
+  unsigned long long Num;
+  if (getAsUnsignedInteger(Parts[0], 10, Num))
+    return std::make_pair(false, Truncated);
+
+  if (Num > 0xFFFFFFULL)
+    return std::make_pair(false, Truncated);
+
+  if (Num > 0xFFFFULL) {
+    Num = 0xFFFFULL;
+    Truncated = true;
+  }
+  Version = Num << 16;
+
+  for (unsigned i = 1, ShiftNum = 8; i < Parts.size() && i < 3;
+       ++i, ShiftNum -= 8) {
+    if (getAsUnsignedInteger(Parts[i], 10, Num))
+      return std::make_pair(false, Truncated);
+
+    if (Num > 0x3FFULL)
+      return std::make_pair(false, Truncated);
+
+    if (Num > 0xFFULL) {
+      Num = 0xFFULL;
+      Truncated = true;
+    }
+    Version |= (Num << ShiftNum);
+  }
+
+  if (Parts.size() > 3)
+    Truncated = true;
+
+  return std::make_pair(true, Truncated);
+}
+
+void PackedVersion::print(raw_ostream &OS) const {
+  OS << format("%d", getMajor());
+  if (getMinor() || getSubminor())
+    OS << format(".%d", getMinor());
+  if (getSubminor())
+    OS << format(".%d", getSubminor());
+}
+
+} // end namespace MachO.
+} // end namespace llvm.