[functional-tests] Check *_restore doesn't touch the metadata if the xml doesn't exists, or isn't xml.

functional-tests/cache-functional-tests.scm

@@ -167,8 +167,16 @@
     "the input file can't be found"
     (with-empty-metadata (md)
       (receive (_ stderr) (run-fail "cache_restore -i no-such-file -o" md)
+        (assert-superblock-untouched md)
         (assert-starts-with "Couldn't stat file" stderr))))
 
+  (define-scenario (cache-restore garbage-input-file)
+    "the input file is just zeroes"
+    (with-empty-metadata (md)
+      (with-temp-file-sized ((xml "cache.xml" 4096))
+        (receive (_ stderr) (run-fail "cache_restore -i " xml "-o" md)
+          (assert-superblock-untouched md)))))
+
   (define-scenario (cache-restore missing-output-file)
     "the output file can't be found"
     (with-cache-xml (xml)

functional-tests/era-functional-tests.scm

@@ -136,6 +136,20 @@
       (receive (_ stderr) (run-fail "era_restore" "-o" md)
         (assert-starts-with "No input file provided." stderr))))
 
+  (define-scenario (era-restore missing-input-file)
+    "the input file can't be found"
+    (with-empty-metadata (md)
+      (receive (_ stderr) (run-fail "era_restore -i no-such-file -o" md)
+        (assert-superblock-untouched md)
+        (assert-starts-with "Couldn't stat file" stderr))))
+
+  (define-scenario (era-restore garbage-input-file)
+    "the input file is just zeroes"
+    (with-empty-metadata (md)
+      (with-temp-file-sized ((xml "era.xml" 4096))
+        (receive (_ stderr) (run-fail "era_restore -i " xml "-o" md)
+          (assert-superblock-untouched md)))))
+
   (define-scenario (era-restore output-unspecified)
     "Fails if no metadata dev specified"
     (with-era-xml (xml)

functional-tests/functional-tests.scm

@@ -20,10 +20,12 @@
     assert-equal
     assert-eof
     assert-starts-with
-    assert-matches)
+    assert-matches
+    assert-superblock-untouched)
 
   (import
     (chezscheme)
+    (bcache block-manager)
     (fmt fmt)
     (list-utils)
     (logging)
@@ -221,5 +223,20 @@
           (unless ((regex pattern) str)
                   (fail (fmt #f "string should match: " pattern ", " str))))
 
+  (define (all-zeroes? ptr count)
+    (let ((u8-ptr (make-ftype-pointer unsigned-8 ptr)))
+     (let loop ((i 0))
+      (if (= count i)
+          #t
+          (if (zero? (ftype-ref unsigned-8 () u8-ptr i))
+              (loop (+ i 1))
+              #f)))))
+
+  (define (assert-superblock-untouched md)
+    (with-bcache (cache md 1)
+      (with-block (b cache 0 (get-flags))
+        (unless (all-zeroes? (block-data b) 4096)
+                (fail "superblock contains non-zero data")))))
+
   )
 

functional-tests/temp-file.scm

@@ -97,9 +97,8 @@
    (define (with-temp-file-sized-thunk filename size fn)
      (with-temp-file-thunk filename
        (lambda (path)
-         (let ((cmd (fmt #f (dsp "fallocate -l ") (wrt size) (dsp " ") (dsp path))))
-          (system cmd)
-          (fn path)))))
+         (system (fmt #f "fallocate -l " (wrt size) " " path))
+         (fn path))))
 
    (define-syntax with-temp-file-sized
      (syntax-rules ()

functional-tests/thin-functional-tests.scm

@@ -5,6 +5,7 @@
 
   (import
     (chezscheme)
+    (bcache block-manager)
     (disk-units)
     (fmt fmt)
     (functional-tests)
@@ -158,8 +159,16 @@
     "the input file can't be found"
     (with-empty-metadata (md)
       (receive (_ stderr) (run-fail "thin_restore -i no-such-file -o" md)
+        (assert-superblock-untouched md)
         (assert-starts-with "Couldn't stat file" stderr))))
 
+  (define-scenario (thin-restore garbage-input-file)
+    "the input file is just zeroes"
+    (with-empty-metadata (md)
+      (with-temp-file-sized ((xml "thin.xml" 4096))
+        (receive (_ stderr) (run-fail "thin_restore -i " xml "-o" md)
+          (assert-superblock-untouched md)))))
+
   (define-scenario (thin-restore missing-output-file)
     "the output file can't be found"
     (with-thin-xml (xml)