Add and use FastAccurateRipChecksumTask

morituri/program/arc.py

@@ -0,0 +1,50 @@
+import logging
+from subprocess import Popen, PIPE
+from os.path import exists
+
+ARB = 'accuraterip-checksum'
+FLAC = 'flac'
+
+def accuraterip_checksum(f, track, tracks, wave=False, v2=False):
+    v = '--accuraterip-v1'
+    if v2:
+        v = '--accuraterip-v2'
+
+    track, tracks = str(track), str(tracks)
+
+    if not wave:
+        flac = Popen([FLAC, '-cds', f], stdout=PIPE)
+
+        arc = Popen([ARB, v, '/dev/stdin', track, tracks],
+                    stdin=flac.stdout, stdout=PIPE, stderr=PIPE)
+    else:
+        arc = Popen([ARB, v, f, track, tracks],
+                    stdout=PIPE, stderr=PIPE)
+
+    if not wave:
+        flac.stdout.close()
+
+    out, err = arc.communicate()
+
+    if not wave:
+        flac.wait()
+        flac_rc = flac.returncode
+
+    arc_rc = arc.returncode
+
+    if not wave and flac_rc != 0:
+        logging.warning('ARC calculation failed: flac return code is non zero')
+        return None
+
+    if arc_rc != 0:
+        logging.warning('ARC calculation failed: arc return code is non zero')
+        return None
+
+    out = out.strip()
+    try:
+        outh = int('0x%s' % out, base=16)
+    except ValueError:
+        logging.warning('ARC output is not usable')
+        return None
+
+    return outh