check exceptions for Popen, error handling improved

5 files changed, 128 insertions, 56 deletions

diff --git a/cutter/formats/command.py b/cutter/formats/command.py
new file mode 100644
index 0000000..72f2e86
--- /dev/null
+++ b/cutter/formats/command.py
@@ -0,0 +1,62 @@
+from .. coding import to_unicode
+
+import subprocess
+import signal
+
+PIPE = subprocess.PIPE
+STDOUT = subprocess.STDOUT
+
+def strsignal(sig):
+	for k, v in signal.__dict__.items():
+		if k.startswith("SIG") and not k.startswith("SIG_"):
+			if v == sig:
+				return k
+
+	return "signal(%d)" % sig
+
+class CommandError(Exception):
+	pass
+
+class Command:
+	def __init__(self, args, stdin=None, stdout=None, stderr=None):
+		self.proc = None
+		self.status = 0
+		self.status_msg = ""
+
+		try:
+			self.proc = subprocess.Popen(args,
+				stdin=stdin, stdout=stdout, stderr=stderr)
+		except OSError as err:
+			self.status = "not started"
+			self.status_msg = err.strerror
+
+	def __getattr__(self, attr):
+		if self.proc is None:
+			raise CommandError("command not started")
+
+		if attr not in ("stdin", "stdout", "stderr"):
+			raise CommandError("unknown attribute '%s'", attr)
+
+		return getattr(self.proc, attr)
+
+	def ready(self):
+		return self.proc is not None
+
+	def get_status(self):
+		return self.status, self.status_msg
+
+	def close(self, msg=""):
+		if self.proc is None:
+			return
+
+		self.status = self.proc.wait()
+		if self.status and self.proc.stderr:
+			self.status_msg = to_unicode(self.proc.stderr.read())
+
+		if msg and not self.status_msg:
+			self.status_msg = msg
+
+		if self.status < 0:
+			self.status = strsignal(-self.status)
+
+		self.proc = None
diff --git a/cutter/formats/decoder.py b/cutter/formats/decoder.py
index 99f2cbe..b57591d 100644
--- a/cutter/formats/decoder.py
+++ b/cutter/formats/decoder.py
@@ -1,8 +1,9 @@
 from . handler import *
+from . command import *
+
 from .. tools import quote
 from .. coding import to_unicode
 
-import subprocess
 import wave
 
 class DecoderError(Exception):
@@ -42,25 +43,20 @@ class Decoder:
 			return data
 
 	def __init__(self, handler, filename, options=None):
-		self.reader = None
-		self.closed = False
 		self.handler = handler
 
 		args = self.handler.decode(filename)
 		self.command = " ".join(map(quote, args))
 
-		self.proc = subprocess.Popen(
-			args, stdout=subprocess.PIPE, stderr=subprocess.PIPE
-		)
+		self.proc = Command(args, stdout=PIPE, stderr=PIPE)
+		if not self.proc.ready():
+			return
 
 		try:
 			self.reader = wave.open(self.proc.stdout, "r")
 		except Exception as exc:
-			self.close()
-			if self.status:
-				self.status_msg = to_unicode(self.proc.stderr.read())
-			else:
-				self.status_msg = "wave.open: %s" % exc
+			self.proc.stdout.close()
+			self.proc.close("Exception: wave.open: %s" % repr(exc))
 			return
 
 		self._channels		= self.reader.getnchannels()
@@ -68,7 +64,7 @@ class Decoder:
 		self._sample_rate	= self.reader.getframerate()
 
 	def ready(self):
-		return self.reader is not None
+		return self.proc.ready()
 
 	def channels(self):
 		return self._channels
@@ -111,23 +107,13 @@ class Decoder:
 		return self.command
 
 	def get_status(self):
-		return self.status, self.status_msg
+		return self.proc.get_status()
 
 	def close(self):
-		if self.closed:
-			return
-
-		if self.reader:
+		if self.proc.ready():
 			self.reader.close()
-
-		if self.proc:
 			self.proc.stdout.close()
-			self.status = self.proc.wait()
-		else:
-			self.status = 0
-
-		self.status_msg = ""
-		self.closed = True
+			self.proc.close()
 
 	def __del__(self):
 		self.close()
diff --git a/cutter/formats/encoder.py b/cutter/formats/encoder.py
index 23d0c51..8689de8 100644
--- a/cutter/formats/encoder.py
+++ b/cutter/formats/encoder.py
@@ -1,3 +1,4 @@
+from . command import *
 from . handler import *
 from .. tools import quote
 
@@ -52,7 +53,6 @@ class Encoder:
 			return getattr(self.fileobj, attr)
 
 	def __init__(self, handler, reader, filename, options):
-		self.closed = False
 		self.handler = handler
 
 		args = self.handler.encode(filename, options, reader.info())
@@ -62,15 +62,20 @@ class Encoder:
 			self.proc = None
 			return
 
-		self.proc = subprocess.Popen(args, stdin=subprocess.PIPE)
+		self.proc = Command(args, stdin=PIPE)
+		if not self.proc.ready():
+			return
 
 		self.reader = reader
 		self.stream = self.SafeStream(self.proc.stdin)
 		self.writer = wave.open(self.stream, "w")
 		self.writer.setparams(reader.wave_params())
 
+	def ready(self):
+		return self.proc.ready()
+
 	def process(self):
-		if self.proc is None:
+		if not self.proc.ready():
 			return
 
 		while True:
@@ -83,13 +88,14 @@ class Encoder:
 	def get_command(self):
 		return self.command
 
-	def close(self):
-		if self.closed or self.proc is None:
-			return
+	def get_status(self):
+		return self.proc.get_status()
 
-		self.writer.close()
-		self.stream.close()
-		self.proc.wait()
+	def close(self):
+		if self.proc and self.proc.ready():
+			self.writer.close()
+			self.stream.close()
+			self.proc.close()
 
 	def __del__(self):
 		self.close()
diff --git a/cutter/formats/wav.py b/cutter/formats/wav.py
index 41e18d9..d614973 100644
--- a/cutter/formats/wav.py
+++ b/cutter/formats/wav.py
@@ -4,6 +4,9 @@ class WavHandler(SoxHandler):
 	name = "wav"
 	ext = "wav"
 
+	def decode(self, filename):
+		return ["cat", filename]
+
 	def encode(self, path, opt, info):
 		return self.sox_args(path, opt, info)
 
diff --git a/cutter/splitter.py b/cutter/splitter.py
index 3109c14..534815b 100644
--- a/cutter/splitter.py
+++ b/cutter/splitter.py
@@ -239,12 +239,11 @@ class Splitter:
 		path = os.path.join(self.dest, trackname)
 
 		printf("copy %s -> %s", quote(file.path), quote(path))
+		printf("\n" if self.opt.dry_run else ": ")
+
 		if self.opt.dry_run:
-			printf("\n")
 			return
 
-		printf(": ")
-
 		try:
 			shutil.copyfile(file.path, path)
 		except Exception as err:
@@ -255,20 +254,40 @@ class Splitter:
 
 		self.tag(track, path)
 
+	@staticmethod
+	def print_command_error(name, stream):
+		status, msg = stream.get_status()
+
+		cmd = stream.get_command()
+		printerr("%s failed (%s), command: %s", name, status, cmd)
+		for line in msg.split("\n"):
+			if len(line):
+				printf("> %s\n", line)
+
 	def open_decode(self, path):
 		stream = formats.decoder_open(path, self.opt)
 
 		if stream is None:
 			printerr("%s: unsupported type", quote(path))
 		elif not stream.ready():
-			printerr("decode failed, command: %s", stream.get_command())
+			self.print_command_error("decode", stream)
+			stream = None
+		else:
+			if self.opt.verbose and self.opt.dry_run:
+				self.print_decode_info(path, stream)
 
-			status, msg = stream.get_status()
-			if not len(msg):
-				printerr("exit code %d", status)
-			else:
-				printerr("exit code %d, stderr:\n%s", status, msg)
+		return stream
+
+	def open_encode(self, reader, path):
+		stream = self.encoder.open(reader, path, self.opt)
 
+		if self.opt.dry_run:
+			if self.opt.verbose:
+				debug("encode: %s", stream.get_command())
+			return stream
+
+		if not stream.ready():
+			self.print_command_error("encode", stream)
 			stream = None
 
 		return stream
@@ -280,9 +299,6 @@ class Splitter:
 			info.type, info.bits_per_sample, info.sample_rate,
 			info.channels)
 
-	def print_encode_info(self, stream):
-		debug("encode: %s", stream.get_command())
-
 	@staticmethod
 	def track_timerange(track):
 		ts = "%8s -" % msf(track.begin)
@@ -302,10 +318,7 @@ class Splitter:
 	def split_file(self, file):
 		stream = self.open_decode(file.path)
 		if not stream:
-			return
-
-		if self.opt.verbose and self.opt.dry_run:
-			self.print_decode_info(file.path, stream)
+			sys.exit(1)
 
 		if file.ntracks() == 1:
 			if not self.is_need_convert(stream.info()):
@@ -324,19 +337,21 @@ class Splitter:
 			trackname = self.track_name(track)
 			path = os.path.join(self.dest, trackname)
 
-			printf("split %s (%s) -> %s", quote(file.path), ts, quote(trackname))
-			printf("\n" if self.opt.dry_run else ": ")
-
 			stream.seek(track.begin)
 			reader = stream.get_reader(self.track_length(track))
 
-			out = self.encoder.open(reader, path, self.opt)
+			out = self.open_encode(reader, path)
+
+			printf("split %s (%s) -> %s", quote(file.path), ts, quote(trackname))
+			printf("\n" if self.opt.dry_run else ": ")
 
 			if self.opt.dry_run:
-				if self.opt.verbose:
-					self.print_encode_info(out)
 				continue
 
+			if out is None:
+				printf("FAILED\n")
+				sys.exit(1)
+
 			out.process()
 			out.close()