[llvm] r350545 - [elfabi] Add option to manually specify file read format

[Armando Montanez via llvm-commits]

Author: amontanez
Date: Mon Jan  7 09:33:10 2019
New Revision: 350545

URL: http://llvm.org/viewvc/llvm-project?rev=350545&view=rev
Log:
[elfabi] Add option to manually specify file read format

Although llvm-elfabi will attempt to read input files without needing the format to be manually specified, doing so has the potential to introduce extraneous errors that can hinder debugging (since multiple readers may fail in attempts to read the file). This change allows the input file format to be manually specified to force elfabi to use a single reader. This makes it easier to test and debug errors specific to a given reader.

Added:
    llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-elf.test
    llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-tbe.test
Modified:
    llvm/trunk/tools/llvm-elfabi/llvm-elfabi.cpp

Added: llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-elf.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-elf.test?rev=350545&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-elf.test (added)
+++ llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-elf.test Mon Jan  7 09:33:10 2019
@@ -0,0 +1,16 @@
+# RUN: not llvm-elfabi --elf %s --emit-tbe=%t  2>&1 | FileCheck %s
+
+--- !tapi-tbe
+SoName: somelib.so
+TbeVersion: 1.0
+Arch: x86_64
+Symbols:
+  foo: { Type: Func }
+  bar: { Type: Object, Size: 42 }
+  baz: { Type: Object, Size: 8 }
+  not: { Type: Object, Undefined: true, Size: 128 }
+  nor: { Type: Func, Undefined: true }
+...
+
+# CHECK: The file was not recognized as a valid object file
+# CHECK: No file readers succeeded reading `{{.*}}read-tbe-as-elf.test` (unsupported/malformed file?)

Added: llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-tbe.test
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-tbe.test?rev=350545&view=auto
==============================================================================
--- llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-tbe.test (added)
+++ llvm/trunk/test/tools/llvm-elfabi/read-tbe-as-tbe.test Mon Jan  7 09:33:10 2019
@@ -0,0 +1,13 @@
+# RUN: llvm-elfabi --tbe %s --emit-tbe=- | FileCheck %s
+
+--- !tapi-tbe
+TbeVersion: 1.0
+Arch: AArch64
+Symbols: {}
+...
+
+# CHECK:      --- !tapi-tbe
+# CHECK-NEXT: TbeVersion: {{[1-9]\d*\.(0|([1-9]\d*))}}
+# CHECK-NEXT: Arch: AArch64
+# CHECK-NEXT: Symbols: {}
+# CHECK-NEXT: ...

Modified: llvm/trunk/tools/llvm-elfabi/llvm-elfabi.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-elfabi/llvm-elfabi.cpp?rev=350545&r1=350544&r2=350545&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-elfabi/llvm-elfabi.cpp (original)
+++ llvm/trunk/tools/llvm-elfabi/llvm-elfabi.cpp Mon Jan  7 09:33:10 2019
@@ -19,10 +19,27 @@
 #include "llvm/TextAPI/ELF/TBEHandler.h"
 #include <string>
 
+namespace llvm {
+namespace elfabi {
+
+enum class FileFormat {
+  TBE,
+  ELF
+};
+
+} // end namespace elfabi
+} // end namespace llvm
+
 using namespace llvm;
 using namespace llvm::elfabi;
 
 // Command line flags:
+cl::opt<FileFormat> InputFileFormat(
+    cl::desc("Force input file format:"),
+    cl::values(clEnumValN(FileFormat::TBE,
+                          "tbe", "Read `input` as text-based ELF stub"),
+               clEnumValN(FileFormat::ELF,
+                          "elf", "Read `input` as ELF binary")));
 cl::opt<std::string> InputFilePath(cl::Positional, cl::desc("input"),
                                    cl::Required);
 cl::opt<std::string>
@@ -67,20 +84,26 @@ static Expected<std::unique_ptr<ELFStub>
   ErrorCollector EC(/*UseFatalErrors=*/false);
 
   // First try to read as a binary (fails fast if not binary).
-  Expected<std::unique_ptr<ELFStub>> StubFromELF =
-      readELFFile(FileReadBuffer->getMemBufferRef());
-  if (StubFromELF) {
-    return std::move(*StubFromELF);
+  if (InputFileFormat.getNumOccurrences() == 0 ||
+      InputFileFormat == FileFormat::ELF) {
+    Expected<std::unique_ptr<ELFStub>> StubFromELF =
+        readELFFile(FileReadBuffer->getMemBufferRef());
+    if (StubFromELF) {
+      return std::move(*StubFromELF);
+    }
+    EC.addError(StubFromELF.takeError(), "BinaryRead");
   }
-  EC.addError(StubFromELF.takeError(), "BinaryRead");
 
   // Fall back to reading as a tbe.
-  Expected<std::unique_ptr<ELFStub>> StubFromTBE =
-      readTBEFromBuffer(FileReadBuffer->getBuffer());
-  if (StubFromTBE) {
-    return std::move(*StubFromTBE);
+  if (InputFileFormat.getNumOccurrences() == 0 ||
+      InputFileFormat == FileFormat::TBE) {
+    Expected<std::unique_ptr<ELFStub>> StubFromTBE =
+        readTBEFromBuffer(FileReadBuffer->getBuffer());
+    if (StubFromTBE) {
+      return std::move(*StubFromTBE);
+    }
+    EC.addError(StubFromTBE.takeError(), "YamlParse");
   }
-  EC.addError(StubFromTBE.takeError(), "YamlParse");
 
   // If both readers fail, build a new error that includes all information.
   EC.addError(createStringError(errc::not_supported,