Add osmpbf.h

The idea is that this file can be included and will include all needed other
files and contain some definitions. Not used yet, though.

.gitignore

@@ -1,3 +1,4 @@
 src/*.pb.h
 src/*.pb.o
 src/libosmpbf.a
+*.swp

src/osmpbf.h

@@ -0,0 +1,20 @@
+#ifndef OSMPBF_H
+#define OSMPBF_H
+
+// this describes the low-level blob storage
+#include <osmpbf/fileformat.pb.h>
+
+// this describes the high-level OSM objects
+#include <osmpbf/osmformat.pb.h>
+
+namespace osmpbf {
+
+    // the maximum size of a blob header in bytes
+    const int max_blob_header_size = 64 * 1024;
+
+    // the maximum size of a blob in bytes
+    const int max_uncompressed_blob_size = 32 * 1024 * 1024;
+
+}
+
+#endif // OSMPBF_H