[ELF] - Add ability for DWARFContextInMemory to exit early when any error happen.

Change introduces error reporting policy for DWARFContextInMemory.
New callback provided by client is able to handle error on it's
side and return Halt or Continue.

That allows to either keep current behavior when parser prints all errors
but continues parsing object or implement something very different, like
stop parsing on a first error and report an error in a client style.

Differential revision: https://reviews.llvm.org/D34328

llvm-svn: 306512

1 files changed, 21 insertions, 9 deletions

diff --git a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
index 38147946175..fdd191e0cbf 100644
--- a/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
+++ b/llvm/lib/DebugInfo/DWARF/DWARFContext.cpp
@@ -870,13 +870,13 @@ static Expected<SymInfo> getSymbolInfo(const object::ObjectFile &Obj,
 
     Expected<uint64_t> SymAddrOrErr = Sym->getAddress();
     if (!SymAddrOrErr)
-      return createError("error: failed to compute symbol address: ",
+      return createError("failed to compute symbol address: ",
                          SymAddrOrErr.takeError());
 
     // Also remember what section this symbol is in for later
     auto SectOrErr = Sym->getSection();
     if (!SectOrErr)
-      return createError("error: failed to get symbol section: ",
+      return createError("failed to get symbol section: ",
                          SectOrErr.takeError());
 
     RSec = *SectOrErr;
@@ -937,8 +937,14 @@ Error DWARFContextInMemory::maybeDecompress(const SectionRef &Sec,
   return Error::success();
 }
 
-DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
-                                           const LoadedObjectInfo *L)
+ErrorPolicy DWARFContextInMemory::defaultErrorHandler(Error E) {
+  errs() << "error: " + toString(std::move(E)) << '\n';
+  return ErrorPolicy::Continue;
+}
+
+DWARFContextInMemory::DWARFContextInMemory(
+    const object::ObjectFile &Obj, const LoadedObjectInfo *L,
+    function_ref<ErrorPolicy(Error)> HandleError)
     : FileName(Obj.getFileName()), IsLittleEndian(Obj.isLittleEndian()),
       AddressSize(Obj.getBytesInAddress()) {
   for (const SectionRef &Section : Obj.sections()) {
@@ -961,9 +967,10 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
       Section.getContents(data);
 
     if (auto Err = maybeDecompress(Section, name, data)) {
-      errs() << "error: failed to decompress '" + name + "', " +
-                    toString(std::move(Err))
-             << '\n';
+      ErrorPolicy EP = HandleError(
+          createError("failed to decompress '" + name + "', ", std::move(Err)));
+      if (EP == ErrorPolicy::Halt)
+        return;
       continue;
     }
 
@@ -1055,7 +1062,8 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
 
       Expected<SymInfo> SymInfoOrErr = getSymbolInfo(Obj, Reloc, L, AddrCache);
       if (!SymInfoOrErr) {
-        errs() << toString(SymInfoOrErr.takeError()) << '\n';
+        if (HandleError(SymInfoOrErr.takeError()) == ErrorPolicy::Halt)
+          return;
         continue;
       }
 
@@ -1064,7 +1072,11 @@ DWARFContextInMemory::DWARFContextInMemory(const object::ObjectFile &Obj,
       if (V.error()) {
         SmallString<32> Name;
         Reloc.getTypeName(Name);
-        errs() << "error: failed to compute relocation: " << Name << "\n";
+        ErrorPolicy EP = HandleError(
+            createError("failed to compute relocation: " + name + ", ",
+                        errorCodeToError(object_error::parse_failed)));
+        if (EP == ErrorPolicy::Halt)
+          return;
         continue;
       }
       RelocAddrEntry Rel = {SymInfoOrErr->SectionIndex, Val};