diff options
Diffstat (limited to 'libbuild2/in')
| -rw-r--r-- | libbuild2/in/init.cxx | 16 | ||||
| -rw-r--r-- | libbuild2/in/rule.cxx | 47 | ||||
| -rw-r--r-- | libbuild2/in/rule.hxx | 5 |
3 files changed, 59 insertions, 9 deletions
diff --git a/libbuild2/in/init.cxx b/libbuild2/in/init.cxx index 6743e31..8bd5909 100644 --- a/libbuild2/in/init.cxx +++ b/libbuild2/in/init.cxx @@ -64,6 +64,22 @@ namespace build2 // vp.insert_alias (im, "in.substitution"); + // Substitution map. Substitutions can be specified as key-value pairs + // rather than buildfile variables. This map is checked before the + // variables. An absent value in key-value has the NULL semantics. + // + // This mechanism has two primary uses: Firstly, it allows us to have + // substitution names that cannot be specified as buildfile variables. + // For example, a name may start with an underscore and thus be + // reserved or it may refer to one of the predefined variables such a + // `include` or `extension` that may have a wrong visibility and/or + // type. + // + // Secondly, this mechanism allows us to encapsulate a group of + // substitutions and pass this group around as a single value. + // + vp.insert<map<string, optional<string>>> ("in.substitutions"); + // Fallback value to use for NULL value substitutions. If unspecified, // NULL substitutions are an error. // diff --git a/libbuild2/in/rule.cxx b/libbuild2/in/rule.cxx index 3aa92a2..d07adfc 100644 --- a/libbuild2/in/rule.cxx +++ b/libbuild2/in/rule.cxx @@ -116,6 +116,11 @@ namespace build2 fail << "invalid substitution mode '" << *s << "'"; } + // Substitution map. + // + const substitution_map* smap ( + cast_null<map<string, optional<string>>> (t["in.substitutions"])); + // NULL substitutions. // optional<string> null; @@ -251,7 +256,7 @@ namespace build2 substitute (location (ip, ln), a, t, name, flags, - strict, null)); + strict, smap, null)); assert (v); // Rule semantics change without version increment? @@ -379,7 +384,7 @@ namespace build2 a, t, dd, dd_skip, s, 0, - nl, sym, strict, null); + nl, sym, strict, smap, null); ofs << s; } @@ -445,6 +450,7 @@ namespace build2 const char* nl, char sym, bool strict, + const substitution_map* smap, const optional<string>& null) const { // Scan the line looking for substiutions in the $<name>$ form. In the @@ -500,8 +506,7 @@ namespace build2 dd, dd_skip, string (s, b + 1, e - b -1), nullopt /* flags */, - strict, - null)) + strict, smap, null)) { replace_newlines (*val, nl); @@ -522,9 +527,10 @@ namespace build2 const string& n, optional<uint64_t> flags, bool strict, + const substitution_map* smap, const optional<string>& null) const { - optional<string> val (substitute (l, a, t, n, flags, strict, null)); + optional<string> val (substitute (l, a, t, n, flags, strict, smap, null)); if (val) { @@ -561,6 +567,7 @@ namespace build2 const string& n, optional<uint64_t> flags, bool strict, + const substitution_map* smap, const optional<string>& null) const { // In the lax mode scan the fragment to make sure it is a variable name @@ -585,7 +592,7 @@ namespace build2 } } - return lookup (l, a, t, n, flags, null); + return lookup (l, a, t, n, flags, smap, null); } string rule:: @@ -593,10 +600,32 @@ namespace build2 action, const target& t, const string& n, optional<uint64_t> flags, + const substitution_map* smap, const optional<string>& null) const { assert (!flags); + // First look in the substitution map. + // + if (smap != nullptr) + { + auto i (smap->find (n)); + + if (i != smap->end ()) + { + if (i->second) + return *i->second; + + if (null) + return *null; + + fail (loc) << "null value in substitution map entry '" << n << "'" << + info << "use in.null to specify null value substiution string"; + } + } + + // Next look for the buildfile variable. + // auto l (t[n]); if (l.defined ()) @@ -607,9 +636,9 @@ namespace build2 { if (null) return *null; - else - fail (loc) << "null value in variable '" << n << "'" << - info << "use in.null to specify null value substiution string"; + + fail (loc) << "null value in variable '" << n << "'" << + info << "use in.null to specify null value substiution string"; } // For typed values call string() for conversion. diff --git a/libbuild2/in/rule.hxx b/libbuild2/in/rule.hxx index bd0d15a..369fd93 100644 --- a/libbuild2/in/rule.hxx +++ b/libbuild2/in/rule.hxx @@ -54,6 +54,7 @@ namespace build2 // Customization hooks and helpers. // + using substitution_map = map<string, optional<string>>; // Perform prerequisite search. // @@ -89,6 +90,7 @@ namespace build2 action, const target&, const string& name, optional<uint64_t> flags, + const substitution_map*, const optional<string>& null) const; // Perform variable substitution. Return nullopt if it should be @@ -100,6 +102,7 @@ namespace build2 const string& name, optional<uint64_t> flags, bool strict, + const substitution_map*, const optional<string>& null) const; // Call the above version and do any necessary depdb saving. @@ -111,6 +114,7 @@ namespace build2 const string& name, optional<uint64_t> flags, bool strict, + const substitution_map*, const optional<string>& null) const; // Process a line of input from the specified position performing any @@ -124,6 +128,7 @@ namespace build2 const char* newline, char sym, bool strict, + const substitution_map*, const optional<string>& null) const; // Replace newlines in a multi-line value with the given newline |