Move cpio end trailer detection to the cpio code

- The fsm shouldn't know any archive format specifics, detect the trailer
  from rpmcpioHeaderRead() and signal EOF through CPIOERR_HDR_TRAILER
  instead.

lib/cpio.c

@@ -21,6 +21,7 @@
 
 #include <rpm/rpmio.h>
 #include <rpm/rpmlog.h>
+#include <rpm/rpmstring.h>
 
 #include "lib/cpio.h"
 
@@ -303,6 +304,9 @@ int rpmcpioHeaderRead(rpmcpio_t cpio, char ** path, struct stat * st)
     rc = rpmcpioReadPad(cpio);
     cpio->fileend = cpio->offset + st->st_size;
 
+    if (!rc && rstreq(*path, CPIO_TRAILER))
+	rc = CPIOERR_HDR_TRAILER;
+
     return rc;
 }
 

lib/fsm.c

@@ -1723,8 +1723,10 @@ int rpmPackageFilesInstall(rpmts ts, rpmte te, rpmfi fi, FD_t cfd,
         rc = rpmcpioHeaderRead(archive, &(fsm->path), &(fsm->sb));
 
 	/* Detect and exit on end-of-payload. */
-	if (!rc && rstreq(fsm->path, CPIO_TRAILER))
+	if (rc == CPIOERR_HDR_TRAILER) {
+	    rc = 0;
 	    break;
+	}
 
 	if (rc) break;