diff options
| -rw-r--r-- | build/parser.cxx | 179 |
1 files changed, 108 insertions, 71 deletions
diff --git a/build/parser.cxx b/build/parser.cxx index b804494..65be0bc 100644 --- a/build/parser.cxx +++ b/build/parser.cxx @@ -1356,12 +1356,38 @@ namespace build // Buildspec parsing. // + // Here is the problem: we "overload" '(' and ')' to mean operation + // application rather than the eval context. At the same time we want + // to use names() to parse names, get variable expansion/function calls, + // quoting, etc. We just need to disable the eval context. The way this + // is done has two parts: Firstly, we parse names in chunks and detect + // and handle the opening paren. In other words, a buildspec like + // 'clean (./)' is "chunked" as 'clean', '(', etc. While this is fairly + // straightforward, there is one snag: concatenating eval contexts, as + // in 'clean(./)'. Normally, this will be treated as a single chunk and + // we don't want that. So here comes the trick (or hack, if you like): + // we will make every opening paren token "separated" (i.e., as if it + // was proceeded by a space). This will disable concatenating eval. In + // fact, we will even go a step further and only do this if we are in + // the original pairs mode. This will allow us to still use eval + // contexts in buildspec, provided that we quote it: '"cle(an)"'. Note + // also that function calls still work as usual: '$filter (clean test)'. + // To disable a function call and make it instead a var that is expanded + // into operation name(s), we can use quoting: '"$ops"(./)'. + // + static void + paren_processor (token& t, const lexer& l) + { + if (t.type == type::lparen && l.mode () == lexer_mode::pairs) + t.separated = true; + } + buildspec parser:: parse_buildspec (istream& is, const std::string& name) { path_ = &name; - lexer l (is, name); + lexer l (is, name, &paren_processor); lexer_ = &l; target_ = nullptr; scope_ = root_ = global_scope; @@ -1405,83 +1431,37 @@ namespace build while (tt != tt_end) { - // We always start with one or more names. No eval context - // support for the time being. + // We always start with one or more names. Eval context + // (lparen) only allowed if quoted. // if (tt != type::name && tt != type::lcbrace && // Untyped name group: '{foo ...' tt != type::dollar && // Variable expansion: '$foo ...' - tt != type::pair_separator) // Empty pair LHS: '=foo ...' + !(tt == type::lparen && lexer_->mode () == lexer_mode::quoted) && + tt != type::pair_separator) // Empty pair LHS: '@foo ...' fail (t) << "operation or target expected instead of " << t; const location l (get_location (t, &path_)); // Start of names. - // This call will produce zero or more names and should stop - // at either tt_end or '('. + // This call will parse the next chunk of output and produce + // zero or more names. // - names_type ns (names (t, tt)); - size_t targets (ns.size ()); - - if (tt == type::lparen) - { - if (targets == 0 || !opname (ns.back ())) - fail (t) << "operation name expected before ("; + names_type ns (names (t, tt, true)); - targets--; // Last one is an operation name. - } - - // Group all the targets into a single operation. In other - // words, 'foo bar' is equivalent to 'build(foo bar)'. + // What these names mean depends on what's next. If it is an + // opening paren, then they are operation/meta-operation names. + // Otherwise they are targets. // - if (targets != 0) + if (tt == type::lparen) // Peeked into by names(). { - if (bs.empty () || !bs.back ().name.empty ()) - bs.push_back (metaopspec ()); // Empty (default) meta operation. - - metaopspec& ms (bs.back ()); - - for (auto i (ns.begin ()), e (i + targets); i != e; ++i) - { - // @@ We may actually want to support this at some point. - // - if (i->qualified ()) - fail (l) << "target name expected instead of " << *i; - - if (opname (*i)) - ms.push_back (opspec (move (i->value))); - else - { - // Do we have the src_base? - // - dir_path src_base; - if (i->pair != '\0') - { - if (i->typed ()) - fail (l) << "expected target src_base instead of " << *i; - - src_base = move (i->dir); - - if (!i->value.empty ()) - src_base /= dir_path (move (i->value)); - - ++i; - assert (i != e); - } - - if (ms.empty () || !ms.back ().name.empty ()) - ms.push_back (opspec ()); // Empty (default) operation. + if (ns.empty ()) + fail (t) << "operation name expected before '('"; - opspec& os (ms.back ()); - os.emplace_back (move (src_base), move (*i)); - } - } - } + for (const name& n: ns) + if (!opname (n)) + fail (l) << "operation name expected instead of '" << n << "'"; - // Handle the operation. - // - if (tt == type::lparen) - { - // Inside '(' and ')' we have another buildspec. + // Inside '(' and ')' we have another, nested, buildspec. // next (t, tt); const location l (get_location (t, &path_)); // Start of nested names. @@ -1494,11 +1474,16 @@ namespace build bool meta (false); for (const metaopspec& nms: nbs) { + // We definitely shouldn't have any meta-operations. + // if (!nms.name.empty ()) fail (l) << "nested meta-operation " << nms.name; if (!meta) { + // If we have any operations in the nested spec, then this + // mean that our names are meta-operation names. + // for (const opspec& nos: nms) { if (!nos.name.empty ()) @@ -1514,12 +1499,15 @@ namespace build // metaopspec object with empty meta-operation name. // assert (nbs.size () == 1); - metaopspec& nmo (nbs.back ()); + const metaopspec& nmo (nbs.back ()); if (meta) { - nmo.name = move (ns.back ().value); - bs.push_back (move (nmo)); + for (name& n: ns) + { + bs.push_back (nmo); + bs.back ().name = move (n.value); + } } else { @@ -1527,16 +1515,65 @@ namespace build // should be just a bunch of targets. // assert (nmo.size () == 1); - opspec& nos (nmo.back ()); + const opspec& nos (nmo.back ()); if (bs.empty () || !bs.back ().name.empty ()) bs.push_back (metaopspec ()); // Empty (default) meta operation. - nos.name = move (ns.back ().value); - bs.back ().push_back (move (nos)); + for (name& n: ns) + { + bs.back ().push_back (nos); + bs.back ().back ().name = move (n.value); + } } - next (t, tt); // Done with ')'. + next (t, tt); // Done with '('. + } + else if (!ns.empty ()) + { + // Group all the targets into a single operation. In other + // words, 'foo bar' is equivalent to 'update(foo bar)'. + // + if (bs.empty () || !bs.back ().name.empty ()) + bs.push_back (metaopspec ()); // Empty (default) meta operation. + + metaopspec& ms (bs.back ()); + + for (auto i (ns.begin ()), e (ns.end ()); i != e; ++i) + { + // @@ We may actually want to support this at some point. + // + if (i->qualified ()) + fail (l) << "target name expected instead of " << *i; + + if (opname (*i)) + ms.push_back (opspec (move (i->value))); + else + { + // Do we have the src_base? + // + dir_path src_base; + if (i->pair != '\0') + { + if (i->typed ()) + fail (l) << "expected target src_base instead of " << *i; + + src_base = move (i->dir); + + if (!i->value.empty ()) + src_base /= dir_path (move (i->value)); + + ++i; + assert (i != e); // Got to have the second half of the pair. + } + + if (ms.empty () || !ms.back ().name.empty ()) + ms.push_back (opspec ()); // Empty (default) operation. + + opspec& os (ms.back ()); + os.emplace_back (move (src_base), move (*i)); + } + } } } |