Allow for retrieval of "memory" type import / export name (#449)

* Store the memory export name

When the memory export is defined in the WASM module,
store the name of the export so that it can be read by
the application.

This is necessary for implementing the JavaScript
`WebAssembly.Module.exports()` function.

* Store the memory import name

When the memory import is defined in the WASM module,
store the name of the import so that it can be read by
the application.

This is necessary for implementing the JavaScript
`WebAssembly.Module.imports()` function.

* Store the table0 export name

When the table export is defined in the WASM module,
store the name of the export so that it can be read by
the application.

This is necessary for implementing the JavaScript
`WebAssembly.Module.exports()` function.

source/m3_env.h

@@ -110,9 +110,12 @@ typedef struct M3Module
 
     IM3Function *           table0;
     u32                     table0Size;
+    const char*             table0ExportName;
 
     M3MemoryInfo            memoryInfo;
+    M3ImportInfo            memoryImport;
     bool                    memoryImported;
+    const char*             memoryExportName;
 
     //bool                    hasWasmCodeCopy;
 

source/m3_parse.c

@@ -184,6 +184,8 @@ _               (Module_AddFunction (io_module, typeIndex, & import))
             {
 _               (ParseType_Memory (& io_module->memoryInfo, & i_bytes, i_end));
                 io_module->memoryImported = true;
+                io_module->memoryImport = import;
+                import = clearImport;
             }
             break;
 
@@ -256,6 +258,18 @@ _       (ReadLEB_u32 (& index, & i_bytes, i_end));
             global->name = utf8;
             utf8 = NULL; // ownership transferred to M3Global
         }
+        else if (exportKind == d_externalKind_memory)
+        {
+            m3_Free (io_module->memoryExportName);
+            io_module->memoryExportName = utf8;
+            utf8 = NULL; // ownership transferred to M3Module
+        }
+        else if (exportKind == d_externalKind_table)
+        {
+            m3_Free (io_module->table0ExportName);
+            io_module->table0ExportName = utf8;
+            utf8 = NULL; // ownership transferred to M3Module
+        }
 
         m3_Free (utf8);
     }