Add a StringLexer utility class that can be used when you have string data that needs to be parsed - I don't think such a general purpose facility is part of LLVM, and I am going to need this, so just add it to lldb_utility

llvm-svn: 215133

lldb/include/lldb/Utility/StringLexer.h

@@ -0,0 +1,62 @@
+//===--------------------- StringLexer.h -------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef utility_StringLexer_h_
+#define utility_StringLexer_h_
+
+#include <string>
+#include <list>
+
+namespace lldb_utility {
+    
+class StringLexer
+{
+public:
+    typedef std::string::size_type Position;
+    typedef std::string::size_type Size;
+
+    typedef std::string::value_type Character;
+    
+    StringLexer (std::string s);
+    
+    StringLexer (const StringLexer& rhs);
+    
+    Character
+    Peek ();
+    
+    bool
+    NextIf (Character c);
+    
+    Character
+    Next ();
+    
+    bool
+    HasAtLeast (Size s);
+    
+    bool
+    HasAny (Character c);
+    
+    void
+    PutBack (Character c);
+    
+    StringLexer&
+    operator = (const StringLexer& rhs);
+    
+private:
+    std::string m_data;
+    Position m_position;
+    std::list<Character> m_putback_data;
+    
+    void
+    Consume();
+};
+
+} // namespace lldb_private
+
+#endif // #ifndef utility_StringLexer_h_

lldb/lldb.xcodeproj/project.pbxproj

@@ -617,6 +617,7 @@
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 		941BCC8114E48C4000BB969C /* SBTypeSummary.h in Headers */ = {isa = PBXBuildFile; fileRef = 9461568814E355F2003A195C /* SBTypeSummary.h */; settings = {ATTRIBUTES = (Public, ); }; };
 		941BCC8214E48C4000BB969C /* SBTypeSynthetic.h in Headers */ = {isa = PBXBuildFile; fileRef = 9461568914E355F2003A195C /* SBTypeSynthetic.h */; settings = {ATTRIBUTES = (Public, ); }; };
+		94380B8219940B0A00BFE4A8 /* StringLexer.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 94380B8119940B0A00BFE4A8 /* StringLexer.cpp */; };
 		944372DC171F6B4300E57C32 /* RegisterContextDummy.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 944372DA171F6B4300E57C32 /* RegisterContextDummy.cpp */; };
 		944372DD171F6B4300E57C32 /* RegisterContextDummy.h in Headers */ = {isa = PBXBuildFile; fileRef = 944372DB171F6B4300E57C32 /* RegisterContextDummy.h */; };
 		9443B122140C18C40013457C /* SBData.cpp in Sources */ = {isa = PBXBuildFile; fileRef = 9443B121140C18C10013457C /* SBData.cpp */; };
@@ -1841,6 +1842,8 @@
 		94094C68163B6CCC0083A547 /* ValueObjectCast.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = ValueObjectCast.h; path = include/lldb/Core/ValueObjectCast.h; sourceTree = "<group>"; };
 		94094C69163B6CD90083A547 /* ValueObjectCast.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = ValueObjectCast.cpp; path = source/Core/ValueObjectCast.cpp; sourceTree = "<group>"; };
 		94145430175D7FDE00284436 /* lldb-versioning.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = "lldb-versioning.h"; path = "include/lldb/lldb-versioning.h"; sourceTree = "<group>"; };
+		94380B8019940B0300BFE4A8 /* StringLexer.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = StringLexer.h; path = include/lldb/Utility/StringLexer.h; sourceTree = "<group>"; };
+		94380B8119940B0A00BFE4A8 /* StringLexer.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = StringLexer.cpp; path = source/Utility/StringLexer.cpp; sourceTree = "<group>"; };
 		944372DA171F6B4300E57C32 /* RegisterContextDummy.cpp */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.cpp.cpp; name = RegisterContextDummy.cpp; path = Utility/RegisterContextDummy.cpp; sourceTree = "<group>"; };
 		944372DB171F6B4300E57C32 /* RegisterContextDummy.h */ = {isa = PBXFileReference; fileEncoding = 4; lastKnownFileType = sourcecode.c.h; name = RegisterContextDummy.h; path = Utility/RegisterContextDummy.h; sourceTree = "<group>"; };
 		9443B120140C18A90013457C /* SBData.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; name = SBData.h; path = include/lldb/API/SBData.h; sourceTree = "<group>"; };
@@ -2821,6 +2824,8 @@
 				2660D9F611922A1300958FBD /* StringExtractor.cpp */,
 				2676A094119C93C8008A98EF /* StringExtractorGDBRemote.h */,
 				2676A093119C93C8008A98EF /* StringExtractorGDBRemote.cpp */,
+				94380B8019940B0300BFE4A8 /* StringLexer.h */,
+				94380B8119940B0A00BFE4A8 /* StringLexer.cpp */,
 				26D1804616CEE12C00EDFB5B /* TimeSpecTimeout.h */,
 				26D1804016CEDF0700EDFB5B /* TimeSpecTimeout.cpp */,
 				94EBAC8313D9EE26009BA64E /* PythonPointer.h */,
@@ -4851,6 +4856,7 @@
 				268900C113353E5F00698AC0 /* DWARFDebugPubnames.cpp in Sources */,
 				268900C213353E5F00698AC0 /* DWARFDebugPubnamesSet.cpp in Sources */,
 				268900C313353E5F00698AC0 /* DWARFDebugRanges.cpp in Sources */,
+				94380B8219940B0A00BFE4A8 /* StringLexer.cpp in Sources */,
 				268900C413353E5F00698AC0 /* DWARFDefines.cpp in Sources */,
 				94D0B10C16D5535900EA9C70 /* LibCxx.cpp in Sources */,
 				268900C513353E5F00698AC0 /* DWARFDIECollection.cpp in Sources */,

lldb/source/Utility/StringLexer.cpp

@@ -0,0 +1,93 @@
+//===--------------------- StringLexer.cpp -----------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "lldb/Utility/StringLexer.h"
+
+using namespace lldb_utility;
+
+StringLexer::StringLexer (std::string s) :
+m_data(s),
+m_position(0),
+m_putback_data()
+{ }
+
+StringLexer::StringLexer (const StringLexer& rhs) :
+m_data(rhs.m_data),
+m_position(rhs.m_position),
+m_putback_data(rhs.m_putback_data)
+{ }
+
+StringLexer::Character
+StringLexer::Peek ()
+{
+    if (m_putback_data.empty())
+        return m_data[m_position];
+    else
+        return m_putback_data.front();
+}
+
+bool
+StringLexer::NextIf (Character c)
+{
+    auto val = Peek();
+    if (val == c)
+    {
+        Next();
+        return true;
+    }
+    return false;
+}
+
+StringLexer::Character
+StringLexer::Next ()
+{
+    auto val = Peek();
+    Consume();
+    return val;
+}
+
+bool
+StringLexer::HasAtLeast (Size s)
+{
+    return m_data.size()-m_position >= s;
+}
+
+
+void
+StringLexer::PutBack (Character c)
+{
+    m_putback_data.push_back(c);
+}
+
+bool
+StringLexer::HasAny (Character c)
+{
+    return m_data.find(c, m_position) != std::string::npos;
+}
+
+void
+StringLexer::Consume()
+{
+    if (m_putback_data.empty())
+        m_position++;
+    else
+        m_putback_data.pop_front();
+}
+
+StringLexer&
+StringLexer::operator = (const StringLexer& rhs)
+{
+    if (this != &rhs)
+    {
+        m_data = rhs.m_data;
+        m_position = rhs.m_position;
+        m_putback_data = rhs.m_putback_data;
+    }
+    return *this;
+}