diff options
Diffstat (limited to 'libbuild2/script/run.cxx')
| -rw-r--r-- | libbuild2/script/run.cxx | 391 |
1 files changed, 243 insertions, 148 deletions
diff --git a/libbuild2/script/run.cxx b/libbuild2/script/run.cxx index 81abdab..b7f3314 100644 --- a/libbuild2/script/run.cxx +++ b/libbuild2/script/run.cxx @@ -9,7 +9,8 @@ # include <libbutl/win32-utility.hxx> // DBG_TERMINATE_PROCESS #endif -#include <ios> // streamsize +#include <ios> // streamsize +#include <cstring> // strchr() #include <libbutl/regex.hxx> #include <libbutl/builtin.hxx> @@ -971,81 +972,201 @@ 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, + stream_reader:: + stream_reader(auto_fd&& in, #ifndef _WIN32 - bool, + bool, #else - bool pipe, + bool pipe, #endif - const optional<deadline>& dl, - const command& deadline_cmd, - const location& ll) + bool ws, bool nl, bool ex, + const optional<deadline>& dl, + const command& dc, + const location& l) + : whitespace_ (ws), + newline_ (nl), + exact_ (ex), + deadline_cmd_ (dc), + location_ (l) { - 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); + is_.open (move (in), fdstream_mode::non_blocking); + deadline_ = dl; + } + else + is_.open (move (in)); + } - const timestamp& dlt (dl->value); + optional<string> stream_reader:: + next () + { + if (!is_.is_open ()) + return nullopt; + + // If eos is not reached, then read and return a character. Otherwise + // close the stream and return nullopt. If the deadline is specified and + // is reached, then return nullopt for the successful deadline (as if + // eof is reached) and fail otherwise. + // + // Set the empty_ flag to false after the first character is read. + // + auto get = [this] () -> optional<char> + { + char r; - for (char buf[4096];; ) + if (deadline_) // Reading a character in the non-blocking mode. { - timestamp now (system_clock::now ()); + fdselect_set fds {is_.fd ()}; - if (dlt <= now || ifdselect (fds, dlt - now) == 0) + // Only fallback to ifdselect() if there is no character immediately + // available. + // + for (;;) { - if (!dl->success) - fail (ll) << cmd_path (deadline_cmd) - << " terminated: execution timeout expired"; - else + streamsize n (is_.readsome (&r, 1)); + + if (n == 1) break; + + if (is_.eof ()) + { + is_.close (); + return nullopt; + } + + const timestamp& dlt (deadline_->value); + timestamp now (system_clock::now ()); + + if (dlt <= now || ifdselect (fds, dlt - now) == 0) + { + is_.close (); + + if (!deadline_->success) + fail (location_) << cmd_path (deadline_cmd_) + << " terminated: execution timeout expired"; + else + return nullopt; + } + } + } + else // Reading a character in the blocking mode. + { + if (is_.peek () == ifdstream::traits_type::eof ()) + { + is_.close (); + return nullopt; } - streamsize n (cin.readsome (buf, sizeof (buf))); + is_.get (r); + } - // Bail out if eos is reached. - // - if (n == 0) - break; + empty_ = false; + return r; + }; + + if (whitespace_) // The whitespace mode. + { + const char* sep (" \n\r\t"); + + // Note that we collapse multiple consecutive whitespaces. + // + optional<char> c; + + // Skip the whitespaces. + // + while ((c = get ()) && strchr (sep, *c) != nullptr) ; - r.append (buf, n); + // Bail out for the trailing whitespace(s) or an empty stream. + // + if (!c) + { + // Return the trailing "blank" after the trailing whitespaces in the + // exact mode, unless the stream is empty. + // + return exact_ && !empty_ ? empty_string : optional<string> (); } + + // Read the word until eof or a whitespace character is encountered. + // + string r (1, *c); + while ((c = get ()) && strchr (sep, *c) == nullptr) + r += *c; + + return optional<string> (move (r)); } - else + else // The newline or no-split mode. { - cin.open (move (in)); - r = cin.read_text (); - } + // Note that we don't collapse multiple consecutive newlines. + // + // Note also that we always sanitize CRs, so in the no-split mode we + // need to loop rather than read the whole text at once. + // + optional<string> r; - cin.close (); + do + { + string l; + optional<char> c; - return r; + // Read the line until eof or newline character is encountered. + // + while ((c = get ()) && *c != '\n') + l += *c; + + // Strip the trailing CRs that can appear while, for example, + // cross-testing Windows target or as a part of msvcrt junk + // production (see above). + // + while (!l.empty () && l.back () == '\r') + l.pop_back (); + + // Append the line. + // + if (!l.empty () || // Non-empty. + c || // Empty, non-trailing. + (exact_ && // Empty, trailing, in the exact mode for + !empty_)) // non-empty stream. + { + if (newline_ || !r) + { + r = move (l); + } + else + { + *r += '\n'; + *r += l; + } + } + } + while (!newline_ && is_.is_open ()); + + return r; + } + } + + string + stream_read (auto_fd&& in, + bool pipe, + const optional<deadline>& dl, + const command& dc, + const location& ll) + { + stream_reader sr (move (in), + pipe, + false /* whitespace */, + false /* newline */, + true /* exact */, + dl, + dc, + ll); + + optional<string> s (sr.next ()); + return s ? move (*s) : empty_string; } // The set pseudo-builtin: set variable from the stdin input. @@ -1087,87 +1208,17 @@ namespace build2 if (vname.empty ()) fail (ll) << "set: empty variable name"; - // Read out the stream content into a string while keeping an eye on - // the deadline. - // - string s (read (move (in), pipe, dl, deadline_cmd, ll)); + stream_reader sr (move (in), pipe, + ops.whitespace (), ops.newline (), ops.exact (), + dl, deadline_cmd, + ll); // Parse the stream content into the variable value. // names ns; - if (!s.empty ()) - { - if (ops.whitespace ()) // The whitespace mode. - { - // Note that we collapse multiple consecutive whitespaces. - // - for (size_t p (0); p != string::npos; ) - { - // Skip the whitespaces. - // - const char* sep (" \n\r\t"); - size_t b (s.find_first_not_of (sep, p)); - - if (b != string::npos) // Word beginning. - { - size_t e (s.find_first_of (sep, b)); // Find the word end. - ns.emplace_back (string (s, b, e != string::npos ? e - b : e)); - - p = e; - } - else // Trailings whitespaces. - { - // Append the trailing "blank" after the trailing whitespaces - // in the exact mode. - // - if (ops.exact ()) - ns.emplace_back (empty_string); - - // Bail out since the end of the string is reached. - // - break; - } - } - } - else // The newline or no-split mode. - { - // Note that we don't collapse multiple consecutive newlines. - // - // Note also that we always sanitize CRs so this loop is always - // needed. - // - for (size_t p (0); p != string::npos; ) - { - size_t e (s.find ('\n', p)); - string l (s, p, e != string::npos ? e - p : e); - - // Strip the trailing CRs that can appear while, for example, - // cross-testing Windows target or as a part of msvcrt junk - // production (see above). - // - while (!l.empty () && l.back () == '\r') - l.pop_back (); - - // Append the line. - // - if (!l.empty () || // Non-empty. - e != string::npos || // Empty, non-trailing. - ops.exact ()) // Empty, trailing, in the exact mode. - { - if (ops.newline () || ns.empty ()) - ns.emplace_back (move (l)); - else - { - ns[0].value += '\n'; - ns[0].value += l; - } - } - - p = e != string::npos ? e + 1 : e; - } - } - } + for (optional<string> s; (s = sr.next ()); ) + ns.emplace_back (move (*s)); env.set_variable (move (vname), move (ns), @@ -1242,7 +1293,7 @@ namespace build2 const iteration_index* ii, size_t li, size_t ci, const location& ll, bool diag, - string* output, + const function<command_function>& cf, bool last_cmd, optional<deadline> dl = nullopt, const command* dl_cmd = nullptr, // env -t <cmd> pipe_command* prev_cmd = nullptr) @@ -1253,8 +1304,10 @@ namespace build2 // if (bc == ec) { - if (output != nullptr) + if (cf != nullptr) { + assert (!last_cmd); // Otherwise we wouldn't be here. + // The pipeline can't be empty. // assert (ifd != nullfd && prev_cmd != nullptr); @@ -1263,15 +1316,14 @@ namespace build2 try { - *output = read (move (ifd), - true /* pipe */, - dl, - dl_cmd != nullptr ? *dl_cmd : c, - ll); + cf (env, strings () /* arguments */, + 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: " + fail (ll) << "unable to read from " << cmd_path (c) << " output: " << e; } } @@ -1329,9 +1381,10 @@ 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. + // Make sure that stdout is not redirected if meant to be read (last_cmd + // is false) or cannot not be produced (last_cmd is true). // - if (last && output != nullptr && c.out) + if (last && c.out && cf != nullptr) fail (ll) << "stdout cannot be redirected"; // True if the process path is not pre-searched and the program path @@ -1345,7 +1398,7 @@ namespace build2 const redirect& in ((c.in ? *c.in : env.in).effective ()); - const redirect* out (!last || output != nullptr + const redirect* out (!last || (cf != nullptr && !last_cmd) ? nullptr // stdout is piped. : &(c.out ? *c.out : env.out).effective ()); @@ -1413,7 +1466,7 @@ namespace build2 if (c.out) fail (ll) << program << " builtin stdout cannot be redirected"; - if (output != nullptr) + if (cf != nullptr && !last_cmd) fail (ll) << program << " builtin stdout cannot be read"; if (c.err) @@ -1620,7 +1673,7 @@ namespace build2 if (c.out) fail (ll) << "set builtin stdout cannot be redirected"; - if (output != nullptr) + if (cf != nullptr && !last_cmd) fail (ll) << "set builtin stdout cannot be read"; if (c.err) @@ -1640,6 +1693,39 @@ namespace build2 return true; } + // If this is the last command in the pipe and the command function is + // specified for it, then call it. + // + if (last && cf != nullptr && last_cmd) + { + // Must be enforced by the caller. + // + assert (!c.out && !c.err && !c.exit); + + try + { + cf (env, c.arguments, + move (ifd), !first, + dl, dl_cmd != nullptr ? *dl_cmd : c, + ll); + } + catch (const io_error& e) + { + diag_record dr (fail (ll)); + + dr << cmd_path (c) << ": unable to read from "; + + if (prev_cmd != nullptr) + dr << cmd_path (prev_cmd->cmd) << " output"; + else + dr << "stdin"; + + dr << ": " << e; + } + + return true; + } + // Open a file for command output redirect if requested explicitly // (file overwrite/append redirects) or for the purpose of the output // validation (none, here_*, file comparison redirects), register the @@ -2220,7 +2306,7 @@ namespace build2 nc, ec, move (ofd.in), ii, li, ci + 1, ll, diag, - output, + cf, last_cmd, dl, dl_cmd, &pc); @@ -2347,7 +2433,7 @@ namespace build2 nc, ec, move (ofd.in), ii, li, ci + 1, ll, diag, - output, + cf, last_cmd, dl, dl_cmd, &pc); @@ -2487,7 +2573,7 @@ namespace build2 const iteration_index* ii, size_t li, const location& ll, bool diag, - string* output) + const function<command_function>& cf, bool last_cmd) { // Commands are numbered sequentially throughout the expression // starting with 1. Number 0 means the command is a single one. @@ -2532,7 +2618,7 @@ namespace build2 p.begin (), p.end (), auto_fd (), ii, li, ci, ll, print, - output); + cf, last_cmd); } ci += p.size (); @@ -2546,13 +2632,18 @@ namespace build2 const command_expr& expr, const iteration_index* ii, size_t li, const location& ll, - string* output) + const function<command_function>& cf, + bool last_cmd) { // 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, ii, li, ll, true /* diag */, output)) + if (!run_expr (env, + expr, + ii, li, ll, + true /* diag */, + cf, last_cmd)) throw failed (); // Assume diagnostics is already printed. } @@ -2561,11 +2652,15 @@ namespace build2 const command_expr& expr, const iteration_index* ii, size_t li, const location& ll, - string* output) + const function<command_function>& cf, bool last_cmd) { // Note that we don't print the expression here (see above). // - return run_expr (env, expr, ii, li, ll, false /* diag */, output); + return run_expr (env, + expr, + ii, li, ll, + false /* diag */, + cf, last_cmd); } void |