diff options
Diffstat (limited to 'libbuild2/script/run.cxx')
| -rw-r--r-- | libbuild2/script/run.cxx | 225 |
1 files changed, 143 insertions, 82 deletions
diff --git a/libbuild2/script/run.cxx b/libbuild2/script/run.cxx index f3b5cad..12078c4 100644 --- a/libbuild2/script/run.cxx +++ b/libbuild2/script/run.cxx @@ -944,6 +944,83 @@ namespace build2 : path (c.program.recall_string ()); } + // Read out the stream content into a string. Throw io_error on the + // underlying OS error. + // + // If the execution deadline is specified, then turn the stream into the + // non-blocking mode reading its content in chunks and with a single + // operation otherwise. If the specified deadline is reached while + // reading the stream, then bail out for the successful deadline and + // fail otherwise. Note that in the former case the result will be + // incomplete, but we leave it to the caller to handle that. + // + // Note that on Windows we can only turn pipe file descriptors into the + // non-blocking mode. Thus, we have no choice but to read from + // descriptors of other types synchronously there. That implies that we + // can potentially block indefinitely reading a file and missing the + // deadline on Windows. Note though, that the user can normally rewrite + // the command, for example, `set foo <<<file` with `cat file | set foo` + // to avoid this problem. + // + static string + read (auto_fd in, +#ifndef _WIN32 + bool, +#else + bool pipe, +#endif + const optional<deadline>& dl, + const command& deadline_cmd, + const location& ll) + { + string r; + ifdstream cin; + +#ifndef _WIN32 + if (dl) +#else + if (dl && pipe) +#endif + { + fdselect_set fds {in.get ()}; + cin.open (move (in), fdstream_mode::non_blocking); + + const timestamp& dlt (dl->value); + + for (char buf[4096];; ) + { + timestamp now (system_clock::now ()); + + if (dlt <= now || ifdselect (fds, dlt - now) == 0) + { + if (!dl->success) + fail (ll) << cmd_path (deadline_cmd) + << " terminated: execution timeout expired"; + else + break; + } + + streamsize n (cin.readsome (buf, sizeof (buf))); + + // Bail out if eos is reached. + // + if (n == 0) + break; + + r.append (buf, n); + } + } + else + { + cin.open (move (in)); + r = cin.read_text (); + } + + cin.close (); + + return r; + } + // The set pseudo-builtin: set variable from the stdin input. // // set [-e|--exact] [(-n|--newline)|(-w|--whitespace)] [<attr>] <var> @@ -952,11 +1029,7 @@ namespace build2 set_builtin (environment& env, const strings& args, auto_fd in, -#ifndef _WIN32 - bool, -#else bool pipe, -#endif const optional<deadline>& dl, const command& deadline_cmd, const location& ll) @@ -988,70 +1061,9 @@ namespace build2 fail (ll) << "set: empty variable name"; // Read out the stream content into a string while keeping an eye on - // the deadline. Then parse it according to the split mode. + // the deadline. // - string s; - { - ifdstream cin; - - // If the execution deadline is specified, then turn the stream into - // the non-blocking mode reading its content in chunks and with a - // single operation otherwise. If the specified deadline is reached - // while reading the stream, then bail out for the successful - // deadline and fail otherwise. Note that in the former case the - // variable value will be incomplete, but we leave it to the caller - // to handle that. - // - // Note that on Windows we can only turn pipe file descriptors into - // the non-blocking mode. Thus, we have no choice but to read from - // descriptors of other types synchronously there. That implies that - // we can potentially block indefinitely reading a file and missing - // the deadline on Windows. Note though, that the user can always - // rewrite `set foo <<<file` with `cat file | set foo` to avoid this - // problem. - // -#ifndef _WIN32 - if (dl) -#else - if (dl && pipe) -#endif - { - fdselect_set fds {in.get ()}; - cin.open (move (in), fdstream_mode::non_blocking); - - const timestamp& dlt (dl->value); - - for (char buf[4096];; ) - { - timestamp now (system_clock::now ()); - - if (dlt <= now || ifdselect (fds, dlt - now) == 0) - { - if (!dl->success) - fail (ll) << cmd_path (deadline_cmd) - << " terminated: execution timeout expired"; - else - break; - } - - streamsize n (cin.readsome (buf, sizeof (buf))); - - // Bail out if eos is reached. - // - if (n == 0) - break; - - s.append (buf, n); - } - } - else - { - cin.open (move (in)); - s = cin.read_text (); - } - - cin.close (); - } + string s (read (move (in), pipe, dl, deadline_cmd, ll)); // Parse the stream content into the variable value. // @@ -1137,7 +1149,7 @@ namespace build2 } catch (const io_error& e) { - fail (ll) << "set: " << e; + fail (ll) << "set: unable to read from stdin: " << e; } catch (const cli::exception& e) { @@ -1202,14 +1214,42 @@ namespace build2 auto_fd ifd, size_t ci, size_t li, const location& ll, bool diag, + string* output, optional<deadline> dl = nullopt, const command* dl_cmd = nullptr, // env -t <cmd> pipe_command* prev_cmd = nullptr) { tracer trace ("script::run_pipe"); - if (bc == ec) // End of the pipeline. + // At the end of the pipeline read out its stdout, if requested. + // + if (bc == ec) + { + if (output != nullptr) + { + // The pipeline can't be empty. + // + assert (ifd != nullfd && prev_cmd != nullptr); + + const command& c (prev_cmd->cmd); + + try + { + *output = read (move (ifd), + true /* pipe */, + dl, + dl_cmd != nullptr ? *dl_cmd : c, + ll); + } + catch (const io_error& e) + { + fail (ll) << "io error reading " << cmd_path (c) << " output: " + << e; + } + } + return true; + } // The overall plan is to run the first command in the pipe, reading its // input from the file descriptor passed (or, for the first command, @@ -1261,6 +1301,11 @@ namespace build2 command_pipe::const_iterator nc (bc + 1); bool last (nc == ec); + // Make sure that stdout is not redirected if meant to be read. + // + if (last && output != nullptr && c.out) + fail (ll) << "stdout cannot be redirected"; + // True if the process path is not pre-searched and the program path // still needs to be resolved. // @@ -1272,7 +1317,7 @@ namespace build2 const redirect& in ((c.in ? *c.in : env.in).effective ()); - const redirect* out (!last + const redirect* out (!last || output != nullptr ? nullptr // stdout is piped. : &(c.out ? *c.out : env.out).effective ()); @@ -1340,6 +1385,9 @@ namespace build2 if (c.out) fail (ll) << program << " builtin stdout cannot be redirected"; + if (output != nullptr) + fail (ll) << program << " builtin stdout cannot be read"; + if (c.err) fail (ll) << program << " builtin stderr cannot be redirected"; @@ -1529,6 +1577,9 @@ namespace build2 if (c.out) fail (ll) << "set builtin stdout cannot be redirected"; + if (output != nullptr) + fail (ll) << "set builtin stdout cannot be read"; + if (c.err) fail (ll) << "set builtin stderr cannot be redirected"; @@ -1661,7 +1712,7 @@ namespace build2 // script failures investigation and, for example, for validation // "tightening". // - if (last) + if (last && out != nullptr) ofd.out = open (*out, 1, osp); else { @@ -1690,7 +1741,7 @@ namespace build2 fail (ll) << "stdout and stderr redirected to each other"; auto_fd& self (mo ? ofd.out : efd); - auto_fd& other (mo ? efd : ofd.out); + auto_fd& other (mo ? efd : ofd.out); try { @@ -1704,9 +1755,9 @@ namespace build2 } } - // All descriptors should be open to the date. + // By now all descriptors should be open. // - assert (ofd.out.get () != -1 && efd.get () != -1); + assert (ofd.out != nullfd && efd != nullfd); // Wait for a process/builtin to complete until the deadline is reached // and return the underlying wait function result (optional<something>). @@ -1756,7 +1807,7 @@ namespace build2 // is exiting on Windows, etc) then just ignore this, postponing // the potential failure till the kill() call. // - l5 ([&]{trace (c->loc) <<"unable to terminate " << prog (c) + l5 ([&]{trace (c->loc) << "unable to terminate " << prog (c) << ": " << e;}); } @@ -2123,6 +2174,7 @@ namespace build2 nc, ec, move (ofd.in), ci + 1, li, ll, diag, + output, dl, dl_cmd, &pc); @@ -2249,6 +2301,7 @@ namespace build2 nc, ec, move (ofd.in), ci + 1, li, ll, diag, + output, dl, dl_cmd, &pc); @@ -2376,7 +2429,7 @@ namespace build2 if (success) success = check_output (pr, esp, isp, err, ll, env, diag, "stderr") && - (!last || + (out == nullptr || check_output (pr, osp, isp, *out, ll, env, diag, "stdout")); return success; @@ -2386,7 +2439,8 @@ namespace build2 run_expr (environment& env, const command_expr& expr, size_t li, const location& ll, - bool diag) + bool diag, + string* output) { // Commands are numbered sequentially throughout the expression // starting with 1. Number 0 means the command is a single one. @@ -2424,10 +2478,15 @@ namespace build2 // with false. // if (!((or_op && r) || (!or_op && !r))) + { + assert (!p.empty ()); + r = run_pipe (env, p.begin (), p.end (), auto_fd (), - ci, li, ll, print); + ci, li, ll, print, + output); + } ci += p.size (); } @@ -2438,24 +2497,26 @@ namespace build2 void run (environment& env, const command_expr& expr, - size_t li, const location& ll) + size_t li, const location& ll, + string* output) { // Note that we don't print the expression at any verbosity level // assuming that the caller does this, potentially providing some // additional information (command type, etc). // - if (!run_expr (env, expr, li, ll, true /* diag */)) + if (!run_expr (env, expr, li, ll, true /* diag */, output)) throw failed (); // Assume diagnostics is already printed. } bool run_if (environment& env, const command_expr& expr, - size_t li, const location& ll) + size_t li, const location& ll, + string* output) { // Note that we don't print the expression here (see above). // - return run_expr (env, expr, li, ll, false /* diag */); + return run_expr (env, expr, li, ll, false /* diag */, output); } void |