diff options
Diffstat (limited to 'libbuild2/config/init.cxx')
| -rw-r--r-- | libbuild2/config/init.cxx | 260 |
1 files changed, 232 insertions, 28 deletions
diff --git a/libbuild2/config/init.cxx b/libbuild2/config/init.cxx index 87b492c..2f134c4 100644 --- a/libbuild2/config/init.cxx +++ b/libbuild2/config/init.cxx @@ -26,6 +26,8 @@ namespace build2 { namespace config { + static const file_rule file_rule_ (true /* check_type */); + void functions (function_map&); // functions.cxx @@ -39,7 +41,7 @@ namespace build2 save_environment (const value& d, const value* b, names& storage) { if (b == nullptr) - return make_pair (reverse (d, storage), "="); + return make_pair (reverse (d, storage, true /* reduce */), "="); // The plan is to iterator over environment variables adding those that // are not in base to storage. There is, however, a complication: we may @@ -100,7 +102,10 @@ namespace build2 // reserved to not be valid module names (`build`). We also currently // treat `import` as special. // - auto& vp (rs.var_pool ()); + // All the variables we enter are qualified so go straight for the + // public variable pool. + // + auto& vp (rs.var_pool (true /* public */)); // NOTE: all config.** variables are by default made (via a pattern) to // be overridable with global visibility. So we must override this if a @@ -175,10 +180,6 @@ namespace build2 if (!d) { - // Used as a variable prefix by configure_execute(). - // - vp.insert ("config"); - // Adjust priority for the config module and import pseudo-module so // that their variables come first in config.build. // @@ -209,6 +210,9 @@ namespace build2 #ifndef BUILD2_BOOTSTRAP extern const char host_config[]; extern const char build2_config[]; + + extern const char host_config_no_warnings[]; + extern const char build2_config_no_warnings[]; #endif bool @@ -238,7 +242,7 @@ namespace build2 ? &extra.module_as<module> () : nullptr); - auto& vp (rs.var_pool ()); + auto& vp (rs.var_pool (true /* public */)); // Note: config.* is pattern-typed to global visibility. // @@ -247,6 +251,60 @@ namespace build2 auto& c_v (vp.insert<uint64_t> ("config.version", false /*ovr*/, v_p)); auto& c_l (vp.insert<paths> ("config.config.load", true /* ovr */)); + // Omit loading the configuration from the config.build file (it is + // still loaded from config.config.load if specified). Similar to + // config.config.load, only values specified on this project's root + // scope and global scope are considered. + // + // Note that this variable is not saved in config.build and is expected + // to always be specified as a command line override. + // + auto& c_u (vp.insert<bool> ("config.config.unload", true /*ovr*/)); + + // Configuration variables to disfigure. + // + // The exact semantics is to ignore these variables when loading + // config.build (and any files specified in config.config.load), letting + // them to take on the default values (more precisely, the current + // implementation undefined them after loading config.build). See also + // config.config.unload. + // + // Besides names, variables can also be specified as patterns in the + // config.<prefix>.(*|**)[<suffix>] form where `*` matches single + // component names (i.e., `foo` but not `foo.bar`), and `**` matches + // single and multi-component names. Currently only single wildcard (`*` + // or `**`) is supported. Additionally, a pattern in the + // config.<prefix>(*|**) form (i.e., without `.` after <prefix>) matches + // config.<prefix>.(*|**) plus config.<prefix> itself (but not + // config.<prefix>foo). + // + // For example, to disfigure all the project configuration variables + // (while preserving all the module configuration variables; note + // quoting to prevent pattern expansion): + // + // b config.config.disfigure="'config.hello**'" + // + // Note that this variable is not saved in config.build and is expected + // to always be specified as a command line override. + // + // We also had the idea of using NULL values as a more natural way to + // undefine a configuration variable, which would only work for non- + // nullable variables (such as project configuration variables) or for + // those where NULL is the default value (most of the others). However, + // this cannot work in our model since we cannot reset a NULL override + // to a default value. So setting the variable itself to some special + // value does not seem to be an option and we have to convey this in + // some other way, such as in config.config.disfigure. Another idea is + // to invent a parallel set of variables, such as disfig.*, that can be + // used for that (though they would still have to be specified with some + // dummy value, for example disfig.hello.fancy=). On the other hand, + // this desire to disfigure individual variables does not seem to be + // very common (we lived without it for years without noticing). So + // it's not clear we need to do something like disfig.* which has a + // wiff of hack to it. + // + auto& c_d (vp.insert<strings> ("config.config.disfigure", true /*ovr*/)); + // Hermetic configurations. // // A hermetic configuration stores environment variables that affect the @@ -328,9 +386,10 @@ namespace build2 save_null_omitted | save_empty_omitted | save_base, &save_environment); - // Load config.build if one exists followed by extra files specified in - // config.config.load (we don't need to worry about disfigure since we - // will never be init'ed). + // Load config.build if one exists (and unless config.config.unload is + // specified) followed by extra files specified in config.config.load + // (we don't need to worry about disfigure since we will never be + // init'ed). // auto load_config = [&rs, &c_v] (istream& is, const path_name& in, @@ -375,15 +434,37 @@ namespace build2 auto load_config_file = [&load_config] (const path& f, const location& l) { path_name fn (f); - ifdstream ifs; - load_config (open_file_or_stdin (fn, ifs), fn, l); + try + { + ifdstream ifs; + load_config (open_file_or_stdin (fn, ifs), fn, l); + } + catch (const io_error& e) + { + fail << "unable to read buildfile " << fn << ": " << e; + } }; + // Load config.build unless requested not to. + // { - path f (config_file (rs)); + // The same semantics as in config.config.load below. + // + bool u; + { + lookup l (rs[c_u]); + u = (l && + (l.belongs (rs) || l.belongs (ctx.global_scope)) && + cast_false<bool> (l)); + } + + if (!u) + { + path f (config_file (rs)); - if (exists (f)) - load_config_file (f, l); + if (exists (f)) + load_config_file (f, l); + } } if (lookup l = rs[c_l]) @@ -406,14 +487,23 @@ namespace build2 const string& s (f.string ()); - if (s[0] != '~') + if (s.empty ()) + fail << "empty path in config.config.load"; + else if (s[0] != '~') load_config_file (f, l); - else if (s == "~host" || s == "~build2") + else if (s == "~host" || s == "~host-no-warnings" || + s == "~build2" || s == "~build2-no-warnings") { #ifdef BUILD2_BOOTSTRAP assert (false); #else - istringstream is (s[1] == 'h' ? host_config : build2_config); + istringstream is (s[1] == 'h' + ? (s.size () == 5 + ? host_config + : host_config_no_warnings) + : (s.size () == 7 + ? build2_config + : build2_config_no_warnings)); load_config (is, path_name (s), l); #endif } @@ -424,6 +514,117 @@ namespace build2 } } + // Undefine variables specified with config.config.disfigure. + // + if (const strings* ns = cast_null<strings> (rs[c_d])) + { + auto p (rs.vars.lookup_namespace ("config")); + + for (auto i (p.first); i != p.second; ) + { + const variable& var (i->first); + + // This can be one of the overrides (__override, __prefix, etc), + // which we skip. + // + if (!var.override ()) + { + bool m (false); + + for (const string& n: *ns) + { + if (n.compare (0, 7, "config.") != 0) + fail << "config.* variable expected in " + << "config.config.disfigure instead of '" << n << "'"; + + size_t p (n.find ('*')); + + if (p == string::npos) + { + if ((m = var.name == n)) + break; + } + else + { + // Pattern in one of these forms: + // + // config.<prefix>.(*|**)[<suffix>] + // config.<prefix>(*|**) + // + // BTW, an alternative way to handle this would be to + // translate it to a path and use our path_match() machinery, + // similar to how we do it for build config include/exclude. + // Perhaps one day when/if we decide to support multiple + // wildcards. + // + if (p == 7) + fail << "config.<prefix>* pattern expected in " + << "config.config.disfigure instead of '" << n << "'"; + + bool r (n[p + 1] == '*'); // Recursive. + + size_t pe; // Prefix end/size. + if (n[p - 1] != '.') + { + // Second form should have no suffix. + // + if (p + (r ? 2 : 1) != n.size ()) + fail << "config.<prefix>(*|**) pattern expected in " + << "config.config.disfigure instead of '" << n << "'"; + + // Match just <prefix>. + // + if ((m = n.compare (0, p, var.name) == 0)) + break; + + pe = p; + } + else + pe = p - 1; + + // Match <prefix> followed by `.`. + // + if (n.compare (0, pe, var.name, 0, pe) != 0 || + var.name[pe] != '.') + continue; + + // Match suffix. + // + size_t sb (p + (r ? 2 : 1)); // Suffix begin. + size_t sn (n.size () - sb); // Suffix size. + + size_t te; // Stem end. + if (sn == 0) // No suffix. + te = var.name.size (); + else + { + if (var.name.size () < pe + 1 + sn) // Too short. + continue; + + te = var.name.size () - sn; + + if (n.compare (sb, sn, var.name, te, sn) != 0) + continue; + } + + // Match stem. + // + if ((m = r || var.name.find ('.', pe + 1) >= te)) + break; + } + } + + if (m) + { + i = rs.vars.erase (i); // Undefine. + continue; + } + } + + ++i; + } + } + // Save and cache the config.config.persist value, if any. // if (m != nullptr) @@ -525,20 +726,23 @@ namespace build2 // Register alias and fallback rule for the configure meta-operation. // - // We need this rule for out-of-any-project dependencies (e.g., - // libraries imported from /usr/lib). We are registring it on the - // global scope similar to builtin rules. - // - rs.global_scope ().insert_rule<mtime_target> ( - configure_id, 0, "config.file", file_rule::instance); - - //@@ outer rs.insert_rule<alias> (configure_id, 0, "config.alias", alias_rule::instance); // This allows a custom configure rule while doing nothing by default. // - rs.insert_rule<target> (configure_id, 0, "config", noop_rule::instance); - rs.insert_rule<file> (configure_id, 0, "config.file", noop_rule::instance); + rs.insert_rule<target> (configure_id, 0, "config.noop", noop_rule::instance); + + // We need this rule for out-of-any-project dependencies (for example, + // libraries imported from /usr/lib). We are registering it on the + // global scope similar to builtin rules. + // + // Note: use target instead of anything more specific (such as + // mtime_target) in order not to take precedence over the rules above. + // + // See a similar rule in the dist module. + // + rs.global_scope ().insert_rule<target> ( + configure_id, 0, "config.file", file_rule_); return true; } |