Detect corrupt symbol files during minidump processing. Recover from the errors and use the good data if possible.

More specifically:
 - Detect corrupt symbols during minidump processing and provide the list of modules with corrupt symbols in the ProcessState.  This will allow listing the corrupt symbol files in the final crash report.
 - Skip and recover from symbol data parse errors - don't give up until 100 parse errors are seen.
 - In order to recover from '\0' (null terminator) in the middle of a symbol file, a couple of methods have to be updated to require both buffer pointer and length.  Previously they required only a buffer pointer (char *) and the size of the buffer was evaluated using strlen which is not reliable when the data is corrupt.  Most of the changes are due to these signature updates.
 - Added and updated unittests.

Also, updated minidump_stackwalk to show a WARNING for corrupt symbols.  Output looks like this:
...
Loaded modules:
0x000da000 - 0x000dafff  Google Chrome Canary  ???  (main)
0x000e0000 - 0x0417dfff  Google Chrome Framework  0.1500.0.3  (WARNING: Corrupt symbols, Google Chrome Framework, 4682A6B4136436C4BFECEB62D498020E0)
0x044a8000 - 0x04571fff  IOBluetooth  0.1.0.0
...
Review URL: https://breakpad.appspot.com/613002

git-svn-id: http://google-breakpad.googlecode.com/svn/trunk@1200 4c0a9323-5329-0410-9bdc-e9ce6186880e

1 files changed, 9 insertions, 1 deletions

diff --git a/src/processor/source_line_resolver_base_types.h b/src/processor/source_line_resolver_base_types.h
index 1dc3d62a..4a9dfb3c 100644
--- a/src/processor/source_line_resolver_base_types.h
+++ b/src/processor/source_line_resolver_base_types.h
@@ -121,7 +121,15 @@ class SourceLineResolverBase::Module {
   // Loads a map from the given buffer in char* type.
   // Does NOT take ownership of memory_buffer (the caller, source line resolver,
   // is the owner of memory_buffer).
-  virtual bool LoadMapFromMemory(char *memory_buffer) = 0;
+  // The passed in |memory buffer| is of size |memory_buffer_size|.  If it is
+  // not null terminated, LoadMapFromMemory will null terminate it by modifying
+  // the passed in buffer.
+  virtual bool LoadMapFromMemory(char *memory_buffer,
+                                 size_t memory_buffer_size) = 0;
+
+  // Tells whether the loaded symbol data is corrupt.  Return value is
+  // undefined, if the symbol data hasn't been loaded yet.
+  virtual bool IsCorrupt() const = 0;
 
   // Looks up the given relative address, and fills the StackFrame struct
   // with the result.