Add support for bbot.sys-install:config.install.root variable

1 files changed, 71 insertions, 23 deletions

diff --git a/bbot/worker/worker.cxx b/bbot/worker/worker.cxx
index 985d77e..d7222b4 100644
--- a/bbot/worker/worker.cxx
+++ b/bbot/worker/worker.cxx
@@ -505,6 +505,26 @@ log_step_id (tracer& t, string& log, step_id id)
   log += '\n';
 }
 
+// Add the specified string to the log as a comment. Unless the string is
+// empty (e.g., a blank line to separate comments), also trace it.
+//
+static void
+log_comment (tracer& t, string& log, const string& s)
+{
+  if (!s.empty ())
+    l3 ([&]{t << s;});
+
+  log += comment_begin;
+
+  if (!s.empty ())
+  {
+    log += ' ';
+    log += s;
+  }
+
+  log += '\n';
+}
+
 // Run the worker script command. Name is used for logging and diagnostics
 // only. Match lines read from the command's stderr against the regular
 // expressions and return the warning result status (instead of success) in
@@ -2104,14 +2124,24 @@ build (size_t argc, const char* argv[])
     // first entry in the PATH environment variable, except for build system
     // modules which supposedly don't install any executables.
     //
+    // Note that normally the config.install.root is expected to be prefixed
+    // with the bpkg.target.create or, as a fallback, b.create or bpkg.create
+    // step ids. However, for testing of the relocatable installations it can
+    // be desirable to extract the archive distribution package content at the
+    // bbot.sys-install.tar.extract step into a different installation
+    // directory. If that's the case, then this directory needs to also be
+    // specified as bbot.sys-install:config.install.root. If specified, this
+    // directory will be preferred as a base for forming the bin/ directory
+    // path.
+    //
     optional<dir_path> install_bin;
 
-    auto config_install_root = [&step_args, &tgt_args] () -> optional<dir_path>
+    auto config_install_root = [&step_args, &tgt_args]
+                               (step_id s,
+                                optional<step_id> f1 = nullopt,
+                                optional<step_id> f2 = nullopt)
+      -> optional<dir_path>
     {
-      step_id s  (step_id::bpkg_target_create);
-      step_id f1 (step_id::b_create);
-      step_id f2 (step_id::bpkg_create);
-
       size_t n (19);
       auto space = [] (char c) {return c == ' ' || c == '\t';};
 
@@ -2140,7 +2170,9 @@ build (size_t argc, const char* argv[])
     {
       if (!module_pkg)
       {
-        install_root = config_install_root ();
+        install_root = config_install_root (step_id::bpkg_target_create,
+                                            step_id::b_create,
+                                            step_id::bpkg_create);
 
         if (install_root)
           install_bin = *install_root / dir_path ("bin");
@@ -3261,24 +3293,17 @@ build (size_t argc, const char* argv[])
                 s += " - ";
                 s += name;
 
-                l3 ([&]{trace << s;});
-
-                r.log += comment_begin;
-                r.log += ' ';
-                r.log += s;
-                r.log += '\n';
+                log_comment (trace, r.log, s);
               };
 
-              r.log += comment_begin;
-              r.log += '\n';
+              log_comment (trace, r.log, "");
 
               log (target_uuid,  "target");
               log (host_uuid,    "host");
               log (module_uuid,  "module");
               log (install_uuid, "install");
 
-              r.log += comment_begin;
-              r.log += '\n';
+              log_comment (trace, r.log, "");
             }
           });
 
@@ -4346,6 +4371,30 @@ build (size_t argc, const char* argv[])
         //
         else if (*bindist == step_id::bpkg_bindist_archive)
         {
+          // If the bbot.sys-install:config.install.root variable is
+          // specified, then make sure the directory it refers to exists by
+          // the time we run `tar -xf`, so that this command doesn't fail
+          // trying to extract into a non-existent directory. Note that we do
+          // that regardless whether the package is a build system module or
+          // not.
+          //
+          optional<dir_path> ir (
+            config_install_root (step_id::bbot_sys_install));
+
+          if (ir)
+            mk_p (trace, &r.log, *ir);
+
+          if (!module_pkg)
+          {
+            if (!ir)
+              ir = config_install_root (step_id::bpkg_target_create,
+                                        step_id::b_create,
+                                        step_id::bpkg_create);
+
+            if (ir)
+              install_bin = *ir / dir_path ("bin");
+          }
+
           for (const char* f: pfs)
           {
             // [sudo] tar -xf <distribution-package-file> <env-config-args>
@@ -4404,12 +4453,6 @@ build (size_t argc, const char* argv[])
             fail_unreached_breakpoint (r);
             break;
           }
-
-          if (!module_pkg)
-          {
-            if (optional<dir_path> ir = config_install_root ())
-              install_bin = *ir / dir_path ("bin");
-          }
         }
         //
         // Fail if the breakpoint refers to a
@@ -4509,7 +4552,12 @@ build (size_t argc, const char* argv[])
             // beginning of the PATH environment variable value, so the
             // installed executables are found first.
             //
-            string paths ("PATH=" + install_bin->string ());
+            const string& ib (install_bin->string ());
+
+            log_comment (trace, r.log,
+                         "add " + ib + " to PATH environment variable");
+
+            string paths ("PATH=" + ib);
 
             if (optional<string> s = getenv ("PATH"))
             {