If URL download fails, delete the partially downloaded file (if it exists). If unzipping fails, print an error, and if the zip was corrupted, delete the corrupted file. Fixes https://github.com/kripken/emscripten/issues/1687.

emsdk

@@ -110,11 +110,13 @@ def unzip(source_filename, dest_dir, unpack_even_if_exists=False):
   print "Unpacking '" + source_filename + "' to '" + dest_dir + "'"
   mkdir_p(dest_dir)
   common_subdir = None
+  try:
     with zipfile.ZipFile(source_filename) as zf:
       # Implement '--strip 1' behavior to unzipping by testing if all the files in the zip reside in a common subdirectory, and if so,
       # we move the output tree at the end of uncompression step.
       for member in zf.infolist():
         words = member.filename.split('/')
+        if len(words) > 1: # If there is a directory component?
           if common_subdir == None:
             common_subdir = words[0]
           elif common_subdir != words[0]:
@@ -130,16 +132,12 @@ def unzip(source_filename, dest_dir, unpack_even_if_exists=False):
         # Path traversal defense copied from
         # http://hg.python.org/cpython/file/tip/Lib/http/server.py#l789
         words = member.filename.split('/')
-#      print "words: " + str(words)
         path = unzip_to_dir
         for word in words[:-1]:
           drive, word = os.path.splitdrive(word)
           head, word = os.path.split(word)
           if word in (os.curdir, os.pardir, ''): continue
           path = os.path.join(path, word)
-#      print "Extracting " + member.filename + " to " + path
-#      zf.extract(member, path)
-#      print "Extracting " + member.filename + " to " + unzip_to_dir
         zf.extract(member, unzip_to_dir)
 
       if common_subdir:
@@ -153,6 +151,13 @@ def unzip(source_filename, dest_dir, unpack_even_if_exists=False):
           shutil.rmtree(unzip_to_dir)
         except:
           pass
+  except zipfile.BadZipfile, e:
+    print "Unzipping file '" + source_filename + "' failed due to reason: " + str(e) + "! Removing the corrupted zip file."
+    rmfile(source_filename)
+    return False
+  except Exception, e:
+    print "Unzipping file '" + source_filename + "' failed due to reason: " + str(e)
+    return False
 
   return True
 
@@ -190,7 +195,7 @@ def download_file(url, dstpath, download_even_if_exists=False):
   try:
     u = urllib2.urlopen(url)
     mkdir_p(os.path.dirname(file_name))
-    f = open(file_name, 'wb')
+    with open(file_name, 'wb') as f: 
       meta = u.info()
       file_size = int(meta.getheaders("Content-Length")[0])
       print "Downloading: %s from %s Bytes: %s" % (file_name, url, file_size)
@@ -207,10 +212,13 @@ def download_file(url, dstpath, download_even_if_exists=False):
           status = r"%10d  [%3.2f%%]" % (file_size_dl, file_size_dl * 100. / file_size)
           status = status + chr(8)*(len(status)+1)
           print status,
-
-    f.close()
   except urllib2.HTTPError, e:
     print "HTTP error with URL '" + url + "': " + str(e)
+    rmfile(file_name)
+    return None
+  except:
+    print "Error downloading URL '" + url + "'!"
+    rmfile(file_name)
     return None
   return file_name