Minidump: Add support for reading/writing strings

Summary:
Strings in minidump files are stored as a 32-bit length field, giving
the length of the string in *bytes*, which is followed by the
appropriate number of UTF16 code units. The string is also supposed to
be null-terminated, and the null-terminator is not a part of the length
field. This patch:
- adds support for reading these strings out of the minidump file (this
  implementation does not depend on proper null-termination)
- adds support for writing them to a minidump file
- using the previous two pieces implements proper (de)serialization of
  the CSDVersion field of the SystemInfo stream. Previously, this was
  only read/written as hex, and no attempt was made to access the
  referenced string -- now this string is read and written correctly.

The changes are tested via yaml2obj|obj2yaml round-trip as well as a
unit test which checks the corner cases of the string deserialization
logic.

Reviewers: jhenderson, zturner, clayborg

Subscribers: llvm-commits, aprantl, markmentovai, amccarth, lldb-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D59775

llvm-svn: 357749

1 files changed, 0 insertions, 2 deletions

diff --git a/llvm/unittests/ObjectYAML/MinidumpYAMLTest.cpp b/llvm/unittests/ObjectYAML/MinidumpYAMLTest.cpp
index d172ccf9301..66d44e06759 100644
--- a/llvm/unittests/ObjectYAML/MinidumpYAMLTest.cpp
+++ b/llvm/unittests/ObjectYAML/MinidumpYAMLTest.cpp
@@ -33,7 +33,6 @@ Streams:
   - Type:            SystemInfo
     Processor Arch:  ARM64
     Platform ID:     Linux
-    CSD Version RVA: 0x01020304
     CPU:
       CPUID:           0x05060708
   - Type:            LinuxMaps
@@ -54,7 +53,6 @@ Streams:
   const SystemInfo &SysInfo = *ExpectedSysInfo;
   EXPECT_EQ(ProcessorArchitecture::ARM64, SysInfo.ProcessorArch);
   EXPECT_EQ(OSPlatform::Linux, SysInfo.PlatformId);
-  EXPECT_EQ(0x01020304u, SysInfo.CSDVersionRVA);
   EXPECT_EQ(0x05060708u, SysInfo.CPU.Arm.CPUID);
 
   EXPECT_EQ(StreamType::LinuxMaps, File.streams()[1].Type);