GP-4123: CppExporter can now emit referenced globals

Ghidra/Features/Base/src/main/help/help/topics/ExporterPlugin/exporter.htm

@@ -275,6 +275,8 @@
             <LI><B>Use C++ Style Comments (//)</B> - Select to use // or /* style comments.</LI>
             
             <LI><B>Emit Data-type Definitions</B> - Select to export a C/C++ definition for each data-type.</LI>
+			
+			<LI><B>Emit Referenced Globals</B> - Select to export a C/C++ declaration for referended global variable.</LI>
             
             <LI><B>Function Tags to Filter</B> - Optional list of function tags to filter which 
             functions are exported. Multiple tags must be comma separated.   Any tags listed will

Ghidra/Features/Decompiler/src/main/java/ghidra/app/util/exporter/CppExporter.java

@@ -4,9 +4,9 @@
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
- * 
+ *
  *      http://www.apache.org/licenses/LICENSE-2.0
- * 
+ *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
@@ -47,6 +47,7 @@ public class CppExporter extends Exporter {
 	public static final String CREATE_HEADER_FILE = "Create Header File (.h)";
 	public static final String USE_CPP_STYLE_COMMENTS = "Use C++ Style Comments (//)";
 	public static final String EMIT_TYPE_DEFINITONS = "Emit Data-type Definitions";
+	public static final String EMIT_REFERENCED_GLOBALS = "Emit Referenced Globals";
 	public static final String FUNCTION_TAG_FILTERS = "Function Tags to Filter";
 	public static final String FUNCTION_TAG_EXCLUDE = "Function Tags Excluded";
 
@@ -56,6 +57,7 @@ public class CppExporter extends Exporter {
 	private boolean isCreateCFile = true;
 	private boolean isUseCppStyleComments = true;
 	private boolean emitDataTypeDefinitions = true;
+	private boolean emitReferencedGlobals = true;
 	private String tagOptions = "";
 
 	private Set<FunctionTag> functionTagSet = new HashSet<>();
@@ -69,7 +71,7 @@ public class CppExporter extends Exporter {
 	}
 
 	public CppExporter(DecompileOptions options, boolean createHeader, boolean createFile,
-			boolean emitTypes, boolean excludeTags, String tags) {
+			boolean emitTypes, boolean emitGlobals, boolean excludeTags, String tags) {
 		this();
 		this.options = options;
 		if (options != null) {
@@ -78,6 +80,7 @@ public class CppExporter extends Exporter {
 		isCreateHeaderFile = createHeader;
 		isCreateCFile = createFile;
 		emitDataTypeDefinitions = emitTypes;
+		emitReferencedGlobals = emitGlobals;
 		excludeMatchingTags = excludeTags;
 		if (tags != null) {
 			tagOptions = tags;
@@ -164,13 +167,14 @@ public class CppExporter extends Exporter {
 		Listing listing = program.getListing();
 		FunctionIterator iterator = listing.getFunctions(addrSet, true);
 		List<Function> functions = new ArrayList<>();
+		Set<String> processedGlobals = new HashSet<>();
 		for (int i = 0; iterator.hasNext(); i++) {
 			//
 			// Write results every so many items so that we don't blow out memory
 			//
 			if (i % 10000 == 0) {
 				List<CPPResult> results = parallelDecompiler.decompileFunctions(functions);
-				writeResults(results, headerWriter, cFileWriter, chunkingMonitor);
+				writeResults(results, processedGlobals, headerWriter, cFileWriter, chunkingMonitor);
 				functions.clear();
 			}
 
@@ -184,7 +188,7 @@ public class CppExporter extends Exporter {
 
 		// handle any remaining functions
 		List<CPPResult> results = parallelDecompiler.decompileFunctions(functions);
-		writeResults(results, headerWriter, cFileWriter, chunkingMonitor);
+		writeResults(results, processedGlobals, headerWriter, cFileWriter, chunkingMonitor);
 	}
 
 	private boolean excludeFunction(Function currentFunction) {
@@ -205,26 +209,37 @@ public class CppExporter extends Exporter {
 		return excludeMatchingTags == hasTag;
 	}
 
-	private void writeResults(List<CPPResult> results, PrintWriter headerWriter,
+	private void writeResults(List<CPPResult> results, Set<String> processedGlobals,
-			PrintWriter cFileWriter, TaskMonitor monitor) throws CancelledException {
+			PrintWriter headerWriter, PrintWriter cFileWriter, TaskMonitor monitor)
+			throws CancelledException {
 		monitor.checkCancelled();
 
 		Collections.sort(results);
 
+		StringBuilder globalDecls = new StringBuilder();
 		StringBuilder headers = new StringBuilder();
 		StringBuilder bodies = new StringBuilder();
+
 		for (CPPResult result : results) {
 			monitor.checkCancelled();
 			if (result == null) {
 				continue;
 			}
-			String headerCode = result.getHeaderCode();
+			if (emitReferencedGlobals) {
+				for (String global : result.globals()) {
+					if (processedGlobals.add(global)) {
+						globalDecls.append(global);
+						globalDecls.append(EOL);
+					}
+				}
+			}
+			String headerCode = result.headerCode();
 			if (headerCode != null) {
 				headers.append(headerCode);
 				headers.append(EOL);
 			}
 
-			String bodyCode = result.getBodyCode();
+			String bodyCode = result.bodyCode();
 			if (bodyCode != null) {
 				bodies.append(bodyCode);
 				bodies.append(EOL);
@@ -237,6 +252,7 @@ public class CppExporter extends Exporter {
 			headerWriter.println(headers.toString());
 		}
 		if (cFileWriter != null) {
+			cFileWriter.print(globalDecls.toString());
 			cFileWriter.print(bodies.toString());
 		}
 	}
@@ -343,6 +359,7 @@ public class CppExporter extends Exporter {
 		list.add(new Option(CREATE_C_FILE, Boolean.valueOf(isCreateCFile)));
 		list.add(new Option(USE_CPP_STYLE_COMMENTS, Boolean.valueOf(isUseCppStyleComments)));
 		list.add(new Option(EMIT_TYPE_DEFINITONS, Boolean.valueOf(emitDataTypeDefinitions)));
+		list.add(new Option(EMIT_REFERENCED_GLOBALS, Boolean.valueOf(emitReferencedGlobals)));
 		list.add(new Option(FUNCTION_TAG_FILTERS, tagOptions));
 		list.add(new Option(FUNCTION_TAG_EXCLUDE, Boolean.valueOf(excludeMatchingTags)));
 		return list;
@@ -365,6 +382,9 @@ public class CppExporter extends Exporter {
 				else if (optName.equals(EMIT_TYPE_DEFINITONS)) {
 					emitDataTypeDefinitions = ((Boolean) option.getValue()).booleanValue();
 				}
+				else if (optName.equals(EMIT_REFERENCED_GLOBALS)) {
+					emitReferencedGlobals = ((Boolean) option.getValue()).booleanValue();
+				}
 				else if (optName.equals(FUNCTION_TAG_FILTERS)) {
 					tagOptions = (String) option.getValue();
 				}
@@ -452,31 +472,12 @@ public class CppExporter extends Exporter {
 // Inner Classes
 //==================================================================================================
 
-	private class CPPResult implements Comparable<CPPResult> {
+	private record CPPResult(Address address, String headerCode, String bodyCode,
-
+			List<String> globals) implements Comparable<CPPResult> {
-		private Address address;
-		private String bodyCode;
-		private String headerCode;
-
-		CPPResult(Address address, String headerCode, String bodyCode) {
-			this.address = address;
-			this.headerCode = headerCode;
-			this.bodyCode = bodyCode;
-		}
-
-		String getHeaderCode() {
-			return headerCode;
-		}
-
-		String getBodyCode() {
-			return bodyCode;
-		}
-
 		@Override
 		public int compareTo(CPPResult other) {
 			return address.compareTo(other.address);
 		}
-
 	}
 
 	private class DecompilerFactory extends CountingBasicFactory<DecompInterface> {
@@ -492,7 +493,7 @@ public class CppExporter extends Exporter {
 			DecompInterface decompiler = new DecompInterface();
 			decompiler.setOptions(options);
 			decompiler.openProgram(program);
-			decompiler.toggleSyntaxTree(false);		// Don't need syntax tree
+			decompiler.toggleSyntaxTree(true);
 			return decompiler;
 		}
 
@@ -532,7 +533,7 @@ public class CppExporter extends Exporter {
 			CodeUnit codeUnitAt = function.getProgram().getListing().getCodeUnitAt(entryPoint);
 			if (codeUnitAt == null || !(codeUnitAt instanceof Instruction)) {
 				return new CPPResult(entryPoint, function.getPrototypeString(false, false) + ';',
-					null);
+					null, List.of());
 			}
 
 			monitor.setMessage("Decompiling " + function.getName());
@@ -546,14 +547,24 @@ public class CppExporter extends Exporter {
 					monitor.incrementProgress(1);
 					return new CPPResult(entryPoint, null,
 						"/*" + EOL + "Unable to decompile '" + function.getName() + "'" + EOL +
-							"Cause: " + errorMessage + EOL + "*/" + EOL);
+							"Cause: " + errorMessage + EOL + "*/" + EOL,
+						List.of());
 				}
 				return null;
 			}
 
 			DecompiledFunction decompiledFunction = dr.getDecompiledFunction();
+			List<String> globals =
+				CollectionUtils.asStream(dr.getHighFunction().getGlobalSymbolMap().getSymbols())
+						.map(hsym -> {
+							String dt = hsym.getDataType().getDisplayName();
+							String name = hsym.getName();
+							String space = dt.endsWith("*") ? "" : " ";
+							return "%s%s%s;".formatted(dt, space, name);
+						})
+						.toList();
 			return new CPPResult(entryPoint, decompiledFunction.getSignature(),
-				decompiledFunction.getC());
+				decompiledFunction.getC(), globals);
 		}
 	}