Add support for dynamic target extraction in addition to prerequisites

This functionality is enabled with the depdb-dyndep --dyn-target option. Only
the make format is supported, where the listed targets are added as ad hoc
group members (unless already specified as static members). This functionality
is not available in the --byproduct mode.

1 files changed, 33 insertions, 8 deletions

diff --git a/libbuild2/build/script/builtin.cli b/libbuild2/build/script/builtin.cli
index 7d0936f..2fba0b0 100644
--- a/libbuild2/build/script/builtin.cli
+++ b/libbuild2/build/script/builtin.cli
@@ -17,8 +17,8 @@ namespace build2
       //
       class depdb_dyndep_options
       {
-        // Note that --byproduct, if any, must be the first option and is
-        // handled ad hoc, kind of as a sub-command.
+        // Note that --byproduct or --dyn-target, if any, must be the first
+        // option and is handled ad hoc.
         //
         // Similarly, --update-{include,exclude} are handled ad hoc and must
         // be literals, similar to the -- separator. They specify prerequisite
@@ -44,16 +44,19 @@ namespace build2
         // and the other for prerequisite, we omit "prerequisite" as that's
         // what we extract by default and most commonly. For example:
         //
-        // --what          --what-target
-        // --default-type  --default-target-type
+        // --what          --target-what
+        // --default-type  --target-default-type
         //
         path --file;                  // Read from file rather than stdin.
 
         string --format;              // Dependency format: make (default).
 
-        string --what;                // Dependency kind, e.g., "header".
+        // Dynamic dependency extraction options.
+        //
+        string --what;                // Prerequisite kind, e.g., "header".
 
-        dir_paths --include-path|-I;  // Search paths for generated files.
+        dir_paths --include-path|-I;  // Search paths for generated
+                                      // prerequisites.
 
         string --default-type;        // Default prerequisite type to use
                                       // if none could be derived from ext.
@@ -64,14 +67,36 @@ namespace build2
                                       // normal mode).
 
         dir_path --cwd;               // Builtin's working directory used
-                                      // to complete relative paths (only
-                                      // in --byproduct mode).
+                                      // to complete relative paths of
+                                      // prerequisites (only in --byproduct
+                                      // mode).
 
         bool --drop-cycles;           // Drop prerequisites that are also
                                       // targets. Only use if you are sure
                                       // such cycles are harmless, that is,
                                       // the output is not affected by such
                                       // prerequisites' content.
+
+        // Dynamic target extraction options.
+        //
+        // This functionality is enabled with the --dyn-target option. Only
+        // the make format is supported, where the listed targets are added as
+        // ad hoc group members (unless already specified as static members).
+        // This functionality is not available in the byproduct mode.
+        //
+        // @@ BTW, here what would likely be more useful than default target
+        //    is the ability to specify custom extension-to-type mapping in
+        //    order to resolve ambiguities. See also the issue with getting
+        //    these options during clean.
+        //
+        string --target-what;         // Target kind, e.g., "source".
+
+        string --target-default-type; // Default target type to use if none
+                                      // could be derived from ext.
+
+        dir_path --target-cwd;        // Builtin's working directory used to
+                                      // complete relative paths of targets.
+
       };
     }
   }