Messages in this thread | | | Date | Tue, 03 Dec 2013 23:18:42 +0400 | From | Stas Sergeev <> | Subject | Re: Large pastes into readline enabled programs causes breakage from v2.6.31 onwards |
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03.12.2013 21:00, Peter Hurley пишет: > Any unit test is specifically designed to break the code under test. > This unit test does in fact break a possible input: note specifically > that the writer is not changing the termios so has no control over > the timing of when the input is received. > > Also note that the test is a simulation; the patch will break any > input stream under the following conditions: > 1. The writer writes an EOF-terminated buffer > 2. All the input is received _except_ the EOF; this is strictly > timing-related and not controllable. > 3. The reader changes the termios from non-canon -> canon. > > At that point the damage is done; the read_flags will indicate > 2 EOFs and the 2nd EOF will be interpreted as end-of-file because > it will appear to begin on a new line. How is this different from the unpatched kernel? In the unpatched kernel, if you happen on reader side to enable icanon while n_tty received all but VEOF (is this possible at all?), then the buffer will be flushed, and the remaining VEOF will get you a nice EOF. So, in the unpatched kernel you get EOF because the buffer gets wiped. On patched kernel you get EOF because of 2 consequitive marks in read_flags. This is intentional, for backward compatibility. What is the problem with that, why do you call it a breakage? Or am I misreading the scenario you describe? -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
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