fix(emscripten): save and restore the stack with a run

Addresses issues with multiple invocations. #760

Co-authored-by: Forrest Li <forrest.li@kitware.com>

Author: thewtex

src/pipeline/PipelineEmscriptenModule.ts

@@ -12,6 +12,8 @@ interface PipelineEmscriptenModule extends EmscriptenModule {
   writeArrayToMemory: typeof writeArrayToMemory;
   writeAsciiToMemory: typeof writeAsciiToMemory;
   AsciiToString: (ptr: number) => string;
+  stackSave: () => number;
+  stackRestore: (ptr: number) => void;
 
   resetModuleStdout: () => void;
   resetModuleStderr: () => void;

src/pipeline/internal/runPipelineEmscripten.ts

@@ -291,6 +291,7 @@ function runPipelineEmscripten (pipelineModule: PipelineEmscriptenModule, args:
 
   pipelineModule.resetModuleStdout()
   pipelineModule.resetModuleStderr()
+  const stackPtr = pipelineModule.stackSave()
   let returnValue = 0
   try {
     returnValue = pipelineModule.callMain(args.slice())
@@ -308,6 +309,8 @@ function runPipelineEmscripten (pipelineModule: PipelineEmscriptenModule, args:
       }
     }
     throw exception
+  } finally {
+    pipelineModule.stackRestore(stackPtr)
   }
   const stdout = pipelineModule.getModuleStdout()
   const stderr = pipelineModule.getModuleStderr()