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+/*
+ * upb - a minimalist implementation of protocol buffers.
+ *
+ * Copyright (c) 2011 Google Inc.  See LICENSE for details.
+ * Author: Josh Haberman <jhaberman@gmail.com>
+ *
+ * A simple example that demonstrates creating a standard message object
+ * and parsing into it, using a dynamic reflection-based approach.
+ *
+ * Note that with this approach there are no strongly-typed struct or class
+ * definitions to use from C -- this is essentially a reflection-based
+ * interface.  Note that parsing and serializing are still very fast since
+ * they are JIT-based.
+ *
+ * If this seems a bit verbose, you may prefer an approach that generates
+ * strongly-typed struct definitions (upb will likely provide this, but it is
+ * not yet implemented).
+ *
+ * TODO: make this file compiled as part of "make examples"
+ * TODO: test that this actually works (WARNING: UNTESTED!)
+ */
+
+#include "upb/msg.h"
+#include "upb/pb/glue.h"
+
+const char *descfile = "example.proto.pb";
+const char *type = "example.SampleMessage";
+const char *msgfile = "sample_message.pb";
+
+int main() {
+  // First we load the descriptor that describes the message into a upb_msgdef.
+  // This could come from a string that is compiled into the program or from a
+  // separate file as we do here.  Since defs always live in a symtab, we
+  // create one of those also.
+  upb_symtab *s = upb_symtab_new();
+  upb_status status = UPB_STATUS_INIT;
+  if (!upb_load_descriptor_file_into_symtab(s, descfile, &status)) {
+    fprintf(stderr, "Couldn't load descriptor file '%s': %s\n", descfile,
+            upb_status_getstr(&status));
+    return -1;
+  }
+
+  const upb_msgdef *md = upb_symtab_lookupmsg(s, type);
+  if (!md) {
+    fprintf(stderr, "Descriptor did not contain type '%s'\n", type);
+    return -1;
+  }
+
+  // Parse a file into a new message object.
+  void *msg = upb_filetonewmsg(msgfile, md, &status);
+  if (!msg) {
+    fprintf(stderr, "Error parsing message file '%s': %s\n", msgfile,
+            upb_status_getstr(&status));
+    return -1;
+  }
+
+  // TODO: Inspect some fields.
+  return 0;
+}