Merge pull request #1773 from lijunzh/sac_string_encoding_flag

Variable string encoding for SAC files

CHANGELOG.txt

@@ -188,6 +188,8 @@ master: (doi: 10.5281/zenodo.165135)
       inheritance. (see #1507)
    * Reference time not written to SAC file when made from scratch
      (see #1575)
+   * Reinforce ASCII encoding in reading non-ASCII SAC files regardless of
+      default encoding setting. (see #1768)
 - obspy.io.sh:
    * Fix writing of long headers for Python 3 (see #1526)
    * Whitespace in header fields is not ignored anymore (see #1552)

obspy/CONTRIBUTORS.txt

@@ -78,3 +78,4 @@ Wassermann, Joachim
 Williams, Mark C.
 Winkelman, Andrew
 Zad, Seyed Kasra Hosseini
+Zhu, Lijun

obspy/io/sac/sactrace.py

@@ -1092,7 +1092,7 @@ def read(cls, source, headonly=False, ascii=False, byteorder=None,
                 val = _ut._clean_str(val, strip_whitespace=False)
                 if val.startswith(native_str('-12345')):
                     val = HD.SNULL
-                hs[i] = val
+                hs[i] = val.encode('ASCII', 'replace')
 
         sac = cls._from_arrays(hf, hi, hs, data)
         if sac.dist is None:

obspy/io/sac/tests/test_core.py

@@ -36,6 +36,7 @@ def setUp(self):
         self.fileseis = os.path.join(self.path, "data", "seism.sac")
         self.file_notascii = os.path.join(self.path, "data",
                                           "non_ascii.sac")
+        self.file_encode = os.path.join(self.path, "data", "test_encode.sac")
         self.testdata = np.array(
             [-8.74227766e-08, -3.09016973e-01,
              -5.87785363e-01, -8.09017122e-01, -9.51056600e-01,
@@ -915,6 +916,13 @@ def test_always_sac_reftime(self):
         self.assertAlmostEqual(tr1.stats.sac.a, a, places=5)
         self.assertEqual(tr1.stats.sac.b, b)
 
+    def test_wrong_encoding(self):
+        """
+        Read SAC file with wrong encoding
+        """
+        tr0 = read(self.file_encode)[0]
+        self.assertEqual(tr0.stats.get('channel'), '????????')
+
 
 def suite():
     return unittest.makeSuite(CoreTestCase, 'test')