diff options
Diffstat (limited to 'libbuild2/script')
| -rw-r--r-- | libbuild2/script/run.cxx | 249 |
1 files changed, 215 insertions, 34 deletions
diff --git a/libbuild2/script/run.cxx b/libbuild2/script/run.cxx index 6f5934e..1106421 100644 --- a/libbuild2/script/run.cxx +++ b/libbuild2/script/run.cxx @@ -1237,6 +1237,17 @@ namespace build2 bool terminated = false; // True if this command has been terminated. + // True if this command has been terminated but we failed to read out + // its stdout and/or stderr streams in the reasonable timeframe (2 + // seconds) after the termination. + // + // Note that this may happen if there is a still running child process + // of the terminated command which has inherited the parent's stdout and + // stderr file descriptors. + // + bool unread_stdout = false; + bool unread_stderr = false; + // Only for diagnostics. // const location& loc; @@ -1397,32 +1408,121 @@ namespace build2 diag_buffer& b (c->dbuf); if (b.is.is_open ()) - fds.emplace_back (b.is.fd (), &b); + fds.emplace_back (b.is.fd (), c); } fds.emplace_back (is.fd ()); fdselect_state& ist (fds.back ()); + size_t unread (fds.size ()); optional<timestamp> dlt (dl ? dl->value : optional<timestamp> ()); // If there are some left-hand side processes/builtins running, then - // terminate them and reset the deadline to nullopt. Otherwise, fail - // straigh away. + // terminate them and, if there are unread stdout/stderr file + // descriptors, then increase the deadline by another 2 seconds and + // return true. In this case the term() should be called again upon + // reaching the timeout. Otherwise return false. If there are no + // left-hand side processes/builtins running, then fail straight away. // // Note that in the former case the further reading will be performed - // without timeout. This, however, is fine since all the processes and - // builtins are terminated and we only need to read out the buffered - // data. - // - auto term = [&dlt, pipeline, &trace, &ll, what] () + // with the adjusted timeout. We assume that this timeout is normally + // sufficient to read out the buffered data written by the already + // terminated processes. If, however, that's not the case (see + // pipe_command for the possible reasons), then term() needs to be + // called for the second time and the reading should be interrupted + // afterwards. + // + auto term = [&dlt, pipeline, &fds, &ist, &is, &unread, + &trace, &ll, what, terminated = false] () mutable -> bool { - if (pipeline != nullptr) + // Can only be called if the deadline is specified. + // + assert (dlt); + + if (pipeline == nullptr) + fail (ll) << what << " terminated: execution timeout expired"; + + if (!terminated) { + // Terminate the pipeline and adjust the deadline. + // + + // Note that if we are still reading the stream and it's a builtin + // stdout, then we need to close it before terminating the pipeline. + // Not doing so can result in blocking this builtin on the write + // operation and thus aborting the build2 process (see term_pipe() + // for details). + // + // Should we do the same for all the pipeline builtins' stderr + // streams? No we don't, since the builtin diagnostics is assumed to + // always fit the pipe buffer (see libbutl/builtin.cxx for details). + // Thus, we will leave them open to fully read out the diagnostics. + // + if (ist.fd != nullfd && pipeline->bltn != nullptr) + { + try + { + is.close (); + } + catch (const io_error&) + { + // Not much we can do here. + } + + ist.fd = nullfd; + --unread; + } + term_pipe (pipeline, trace); - dlt = nullopt; + terminated = true; + + if (unread != 0) + dlt = system_clock::now () + chrono::seconds (2); + + return unread != 0; } else - fail (ll) << what << " terminated: execution timeout expired"; + { + // Set the unread_{stderr,stdout} flags to true for the commands + // whose streams are not fully read yet. + // + + // Can only be called after the first call of term() which would + // throw failed if pipeline is NULL. + // + assert (pipeline != nullptr); + + for (fdselect_state& s: fds) + { + if (s.fd != nullfd) + { + if (s.data != nullptr) // stderr. + { + pipe_command* c (static_cast<pipe_command*> (s.data)); + + c->unread_stderr = true; + + // Let's also close the stderr stream not to confuse + // diag_buffer::close() with a not fully read stream (eof is + // not reached, etc). + // + try + { + c->dbuf.is.close (); + } + catch (const io_error&) + { + // Not much we can do here. Anyway the diagnostics will be + // issued by complete_pipe(). + } + } + else // stdout. + pipeline->unread_stdout = true; + } + } + + return false; + } }; // Note that on Windows if the file descriptor is not a pipe, then @@ -1434,7 +1534,7 @@ namespace build2 // return true and thus no ifdselect() calls will ever be made. // string s; - for (size_t unread (fds.size ()); unread != 0;) + while (unread != 0) { // Read any pending data from the input stream. // @@ -1448,7 +1548,10 @@ namespace build2 // blocking file descriptor. // if (dlt && *dlt <= system_clock::now ()) - term (); + { + if (!term ()) + break; + } if (sr.next (s)) { @@ -1480,8 +1583,10 @@ namespace build2 if (*dlt <= now || ifdselect (fds, *dlt - now) == 0) { - term (); - continue; + if (term ()) + continue; + else + break; } } else @@ -1493,7 +1598,7 @@ namespace build2 { if (s.ready && s.data != nullptr && - !static_cast<diag_buffer*> (s.data)->read ()) + !static_cast<pipe_command*> (s.data)->dbuf.read ()) { s.fd = nullfd; --unread; @@ -2238,10 +2343,14 @@ namespace build2 // Read out all the pipeline's buffered strerr streams watching for the // deadline, if specified. If the deadline is reached, then terminate - // the whole pipeline, reset the deadline to nullopt, and continue - // reading. Note that the further reading will be performed without - // timeout. This, however, is fine since all the processes and builtins - // are terminated and we only need to read out the buffered data. + // the whole pipeline, move the deadline by another 2 seconds, and + // continue reading. + // + // Note that we assume that this timeout increment is normally + // sufficient to read out the buffered data written by the already + // terminated processes. If, however, that's not the case (see + // pipe_command for the possible reasons), then we just set + // unread_stderr flag to true for such commands and bail out. // // Also note that this is a reduced version of the above read() function. // @@ -2253,13 +2362,15 @@ namespace build2 diag_buffer& b (c->dbuf); if (b.is.is_open ()) - fds.emplace_back (b.is.fd (), &b); + fds.emplace_back (b.is.fd (), c); } // Note that the current command deadline is the earliest (see above). // optional<timestamp> dlt (pc.dl ? pc.dl->value : optional<timestamp> ()); + bool terminated (false); + for (size_t unread (fds.size ()); unread != 0;) { try @@ -2272,9 +2383,37 @@ namespace build2 if (*dlt <= now || ifdselect (fds, *dlt - now) == 0) { - term_pipe (&pc, trace); - dlt = nullopt; - continue; + if (!terminated) + { + term_pipe (&pc, trace); + terminated = true; + + dlt = system_clock::now () + chrono::seconds (2); + continue; + } + else + { + for (fdselect_state& s: fds) + { + if (s.fd != nullfd) + { + pipe_command* c (static_cast<pipe_command*> (s.data)); + + c->unread_stderr = true; + + // Let's also close the stderr stream not to confuse + // diag_buffer::close() (see read() for details). + // + try + { + c->dbuf.is.close (); + } + catch (const io_error&) {} + } + } + + break; + } } } else @@ -2282,7 +2421,8 @@ namespace build2 for (fdselect_state& s: fds) { - if (s.ready && !static_cast<diag_buffer*> (s.data)->read ()) + if (s.ready && + !static_cast<pipe_command*> (s.data)->dbuf.read ()) { s.fd = nullfd; --unread; @@ -2336,10 +2476,11 @@ namespace build2 // Iterate over the pipeline processes and builtins left to right, // printing their stderr if buffered and issuing the diagnostics if the // exit code is not available (terminated abnormally or due to a - // deadline) or is unexpected. Throw failed at the end if the exit code - // for any of them is not available. Return false if exit code for any - // of them is unexpected (the return is used, for example, in the if- - // conditions). + // deadline), is unexpected, or stdout and/or stderr was not fully + // read. Throw failed at the end if the exit code for any of them is not + // available or stdout and/or stderr was not fully read. Return false if + // exit code for any of them is unexpected (the return is used, for + // example, in the if-conditions). // // Note: must be called after wait_pipe() and only once. // @@ -2410,6 +2551,30 @@ namespace build2 path pr (cmd_path (cmd)); + // Print the diagnostics if the command stdout and/or stderr are not + // fully read. + // + auto unread_output_diag = [&dr, c, w, &pr] (bool main_error) + { + if (main_error) + dr << error (c->loc) << w << ' ' << pr << ' '; + else + dr << error; + + if (c->unread_stdout) + { + dr << "stdout "; + + if (c->unread_stderr) + dr << "and "; + } + + if (c->unread_stderr) + dr << "stderr "; + + dr << "not closed after exit"; + }; + // Fail if the process is terminated due to reaching the deadline. // if (!exit) @@ -2417,6 +2582,9 @@ namespace build2 dr << error (ll) << w << ' ' << pr << " terminated: execution timeout expired"; + if (c->unread_stdout || c->unread_stderr) + unread_output_diag (false /* main_error */); + if (verb == 1) { dr << info << "command line: "; @@ -2443,10 +2611,18 @@ namespace build2 valid = exit->code () < 256; #endif - // In the presense of a valid exit code we print the diagnostics - // and return false rather than throw. + // In the presense of a valid exit code and given stdout and + // stderr are fully read out we print the diagnostics and return + // false rather than throw. + // + // Note that there can be a race, so that the process we have + // terminated due to reaching the deadline has in fact exited + // normally. Thus, the 'unread stderr' situation can also happen + // to a successfully terminated process. If that's the case, we + // report this problem as the main error and the secondary error + // otherwise. // - if (!valid) + if (!valid || c->unread_stdout || c->unread_stderr) fail = true; exit_comparison cmp (cmd.exit @@ -2473,11 +2649,11 @@ namespace build2 uint16_t ec (exit->code ()); // Make sure printed as integer. if (!valid) + { dr << "exit code " << ec << " out of 0-255 range"; + } else { - assert (!success && diag); - if (cmd.exit) dr << "exit code " << ec << (cmp == exit_comparison::eq ? " != " : " == ") @@ -2487,6 +2663,9 @@ namespace build2 } } + if (c->unread_stdout || c->unread_stderr) + unread_output_diag (false /* main_error */); + if (verb == 1) { dr << info << "command line: "; @@ -2506,6 +2685,8 @@ namespace build2 // print_file (dr, *c->esp, ll); } + else if (c->unread_stdout || c->unread_stderr) + unread_output_diag (true /* main_error */); } // Now print the buffered stderr, if present, and/or flush the |