def scan_cha(d):
last_file = {}
for f in os.listdir(d):
try:
(net, sta, loc, cha, ext, year, doy) = f.split('.')
nets.add((net, int(year)))
except ValueError:
logs.error("invalid SDS file:" + p, True)
continue
if (net, sta, loc, cha) not in timespan:
continue
try:
if doy > last_file[loc][0]:
last_file[loc] = (doy, f)
except KeyError:
last_file[loc] = (doy, f)
for (loc, (doy, f)) in last_file.items():
with open(d + '/' + f, 'rb') as fd:
nslc = tuple(f.split('.')[:4])
rec = mseedlite.Record(fd)
fd.seek(-rec.size, 2)
rec = mseedlite.Record(fd)
ts = timespan[nslc]
if ts.start < rec.end_time < ts.end:
ts.start = rec.end_time
elif rec.end_time >= ts.end:
del timespan[nslc]
def __time2recno(self, msFile, reclen, timeStart, recStart, timeEnd, recEnd, searchTime):
if searchTime <= timeStart:
msFile.seek(recStart * reclen)
rec = mseedlite.Record(msFile)
return (recStart, rec.end_time)
if searchTime >= timeEnd:
msFile.seek(recEnd * reclen)
rec = mseedlite.Record(msFile)
return (recEnd, rec.end_time)
t1 = timeStart
r1 = recStart
t2 = timeEnd
r2 = recEnd
rn = int(r1 + (r2 - r1) * _total_seconds(searchTime - t1) / _total_seconds(t2 - t1))
if rn < recStart:
rn = recStart
if rn > recEnd:
rn = recEnd
while True:
msFile.seek(rn * reclen)
rec = mseedlite.Record(msFile)
if rec.begin_time < searchTime:
r1 = rn
t1 = rec.begin_time
if t1 == t2:
break
rn = int(r1 + (r2 - r1) * _total_seconds(searchTime - t1) / _total_seconds(t2 - t1))
if rn < recStart:
rn = recStart
if rn > recEnd:
rn = recEnd
if rn == r1:
break
else:
r2 = rn
t2 = rec.begin_time
if t1 == t2:
break
rn = int(r2 - (r2 - r1) * _total_seconds(t2 - searchTime) / _total_seconds(t2 - t1))
if rn < recStart:
rn = recStart
if rn > recEnd:
rn = recEnd
if rn == r2:
break
return (rn, rec.end_time)
def __getWaveform(self, startt, endt, msFile, bufferSize):
if startt >= endt:
return
rec = mseedlite.Record(msFile)
reclen = rec.size
recStart = 0
timeStart = rec.begin_time
if rec.begin_time >= endt:
return
msFile.seek(-reclen, 2)
rec = mseedlite.Record(msFile)
recEnd = msFile.tell() / reclen - 1
timeEnd = rec.begin_time
if rec.end_time <= startt:
return
if timeStart >= timeEnd:
Logging.error("%s: overlap detected (start=%s, end=%s)" % (msFile.name, timeStart, timeEnd))
return
(lower, et1) = self.__time2recno(msFile, reclen, timeStart, recStart, timeEnd, recEnd, startt)
(upper, et2) = self.__time2recno(msFile, reclen, startt, lower, timeEnd, recEnd, endt)
if upper < lower:
Logging.error("%s: overlap detected (lower=%d, upper=%d)" % (msFile.name, lower, upper))
upper = lower
msFile.seek(lower * reclen)
remaining = (upper - lower + 1) * reclen
check = True
if bufferSize % reclen:
bufferSize += reclen - bufferSize % reclen
while remaining > 0:
size = min(remaining, bufferSize)
data = msFile.read(size)
remaining -= size
offset = 0
if not data:
return
if check:
while offset < len(data):
rec = mseedlite.Record(data[offset:offset+reclen])
if rec.begin_time >= endt:
return
if rec.end_time > startt:
break
offset += reclen
check = False
if offset < len(data):
yield data[offset:] if offset else data
while True:
data = msFile.read(reclen)
if not data:
return
rec = mseedlite.Record(data)
if rec.begin_time >= endt:
return
yield data