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I transfered a file from remote Debian host to my local Windows 10 host using SecureFX.
I found that the file's last modifed date was ‎1900‎/‎1‎/1‎,‏‎0:00:00 on Windows.
I tried to serve this file to be downloaded, and it crashed as follows:
Exception happened during processing of request from ('192.168.1.102', 50978)
Traceback (most recent call last):
 File "C:\Python27\lib\SocketServer.py", line 295, in _handle_request_noblock
 self.process_request(request, client_address)
 File "C:\Python27\lib\SocketServer.py", line 321, in process_request
 self.finish_request(request, client_address)
 File "C:\Python27\lib\SocketServer.py", line 334, in finish_request
 self.RequestHandlerClass(request, client_address, self)
 File "C:\Python27\lib\SocketServer.py", line 655, in __init__
 self.handle()
 File "C:\Python27\lib\BaseHTTPServer.py", line 340, in handle
 self.handle_one_request()
 File "C:\Python27\lib\BaseHTTPServer.py", line 328, in handle_one_request
 method()
 File "C:\Python27\lib\SimpleHTTPServer.py", line 45, in do_GET
 f = self.send_head()
 File "C:\Python27\lib\SimpleHTTPServer.py", line 103, in send_head
 self.send_header("Last-Modified", self.date_time_string(fs.st_mtime))
 File "C:\Python27\lib\BaseHTTPServer.py", line 468, in date_time_string
 year, month, day, hh, mm, ss, wd, y, z = time.gmtime(timestamp)
ValueError: (22, 'Invalid argument')
I have checked the source code, and found it was because of the last modifed date of the file, I got this in console:
>>> os.fstat(f.fileno())
nt.stat_result(st_mode=33206, st_ino=4785074604093500L, st_dev=0L, st_nlink=1, st_uid=0, st_gid=0, st_size=3406L, st_atime=1446477520L, st_mtime=-2209017600L, st_ctime=1446370767L)
-2209017600L cannot be handled by "time.gmtime()" method and it throwed 
error

upload a sample test file

I think your test file’s time is lost on the web server. On Linux it is pretty easy to make a file with an arbitrary time; maybe Windows has an equivalent:
$ touch -d "1 Jan 1900" test
I experimented with Wine, and it seems gmtime() raises ValueError on Python 2 and OSError on Python 3 for negative times, but under Linux negative times are handled successfully. (Wine seems to wrap the st_mtime field to a 32-bit unsigned value though, so I am unable to reproduce the original problem.)
The "time" module documentation says "The functions in this module may not handle dates and times before the epoch", so maybe the HTTP module should be fixed to handle a ValueError (or OSError on Python 3).

I'm afraid we can't say negative epoch is handled successfully on Linux.
Use $ touch -d "1 Jan 1900" test as a test, time.gmtime(os.fstat(f.fileno()).st_mtime) gives time.struct_time(tm_year=1899, tm_mon=12, tm_mday=31, tm_hour=15, tm_min=54, tm_sec=17, tm_wday=6, tm_yday=365, tm_isdst=0), which does not equals "1 Jan 1900". I think this is caused by python gmtime directly uses gmtime in C. Use the epoch of "1 Jan 1900" with C's gmtime does not give a right result. And while I am searching, I can not find any evidence that gmtime in C can give a right result with a negtive epoch.
And when I try the epoch of "1 Jan 1900" with "date -d @", it can generate the right result.

Perhaps you have a timezone set (I don’t). This might work better:
touch -d "1 Jan 1900 UTC" test
My thinking is if os.stat() returns a negative timestamp from the OS (GNU C library in the case of Linux), it may be worth trying gmtime() on that value since it also calls the OS (glibc) function.

You're right. Actually I do think of timezone when I do the experiment. But I think different timezone will only affect the hour. It turns out I should learn more about time.

Does this affect 3.x also? I would expect that it does.
The question for this issue is whether the program should stop on a gmtime error and say "I will not serve this file until you fix the modification time." or whether it should catch and workaround the problem and merely warn about the mtime.
For the latter, BaseHTTPServer could catch the gmtime error and use the current time instead. Or SimpleHTTPServer could catch the exception and omit the Last Modified: header, if that is allowed. I believe the purpose of this header is for caching, and the current time would say to replace any cached value.

I assume it affects Python 3, though I suspect the exception is OSError, not ValueError. But it would be good if someone with Windows (or other affected OS) could confirm.
I think the server should serve the file, with just a best-effort attempt to serve the timestamp. Some other options:
* Maybe using datetime rather than the OS’s gmtime() would be more reliable
* Omit the Last-Modified header if the timestamp cannot be represented
* Make time.gmtime() more platform-independent (probably against the original spirit of the module)
I don’t think setting Last-Modified to the current time is a particularly good idea. I guess omitting the field would have a similar effect on caching, without actually serving a misleading value.