Move parse_cmdline() to libbuild2

1 files changed, 4 insertions, 403 deletions

diff --git a/build2/b.cxx b/build2/b.cxx
index 03ded28..95be718 100644
--- a/build2/b.cxx
+++ b/build2/b.cxx
@@ -11,17 +11,14 @@
 #  include <locale>
 #endif
 
-#include <limits>
 #include <sstream>
-#include <cstring>   // strcmp(), strchr()
 #include <typeinfo>
 #include <iostream>  // cout
 #include <exception> // terminate(), set_terminate(), terminate_handler
 
 #include <libbutl/pager.hxx>
-#include <libbutl/fdstream.hxx>        // stderr_fd(), fdterm()
-#include <libbutl/backtrace.hxx>       // backtrace()
-#include <libbutl/default-options.hxx>
+#include <libbutl/fdstream.hxx>  // stderr_fd(), fdterm()
+#include <libbutl/backtrace.hxx> // backtrace()
 
 #include <libbuild2/types.hxx>
 #include <libbuild2/utility.hxx>
@@ -44,7 +41,8 @@
 
 #include <libbuild2/parser.hxx>
 
-#include <build2/b-options.hxx>
+#include <libbuild2/cmdline.hxx>
+#include <libbuild2/b-options.hxx>
 
 // Build system modules.
 //
@@ -71,403 +69,6 @@ using namespace std;
 
 namespace build2
 {
-  struct cmdline
-  {
-    strings cmd_vars;
-    string buildspec;
-    uint16_t verbosity;
-  };
-
-  static cmdline
-  parse_cmdline (tracer& trace, int argc, char* argv[], options& ops)
-  {
-    // @@ cl namespace
-
-    // Note that the diagnostics verbosity level can only be calculated after
-    // default options are loaded and merged (see below). Thus, until then we
-    // refer to the verbosity level specified on the command line.
-    //
-    auto verbosity = [&ops] ()
-    {
-      uint16_t v (
-        ops.verbose_specified ()
-        ? ops.verbose ()
-        : ops.V () ? 3 : ops.v () ? 2 : ops.quiet () || ops.silent () ? 0 : 1);
-      return v;
-    };
-
-    cmdline r;
-
-    // We want to be able to specify options, vars, and buildspecs in any
-    // order (it is really handy to just add -v at the end of the command
-    // line).
-    //
-    try
-    {
-      // Command line arguments starting position.
-      //
-      // We want the positions of the command line arguments to be after the
-      // default options files. Normally that would be achieved by passing the
-      // last position of the previous scanner to the next. The problem is
-      // that we parse the command line arguments first (for good reasons).
-      // Also the default options files parsing machinery needs the maximum
-      // number of arguments to be specified and assigns the positions below
-      // this value (see load_default_options() for details). So we are going
-      // to "reserve" the first half of the size_t value range for the default
-      // options positions and the second half for the command line arguments
-      // positions.
-      //
-      size_t args_pos (numeric_limits<size_t>::max () / 2);
-      cl::argv_file_scanner scan (argc, argv, "--options-file", args_pos);
-
-      size_t argn (0);       // Argument count.
-      bool shortcut (false); // True if the shortcut syntax is used.
-
-      for (bool opt (true), var (true); scan.more (); )
-      {
-        if (opt)
-        {
-          // Parse the next chunk of options until we reach an argument (or
-          // eos).
-          //
-          if (ops.parse (scan) && !scan.more ())
-            break;
-
-          // If we see first "--", then we are done parsing options.
-          //
-          if (strcmp (scan.peek (), "--") == 0)
-          {
-            scan.next ();
-            opt = false;
-            continue;
-          }
-
-          // Fall through.
-        }
-
-        const char* s (scan.next ());
-
-        // See if this is a command line variable. What if someone needs to
-        // pass a buildspec that contains '='? One way to support this would
-        // be to quote such a buildspec (e.g., "'/tmp/foo=bar/'"). Or invent
-        // another separator. Or use a second "--". Actually, let's just do
-        // the second "--".
-        //
-        if (var)
-        {
-          // If we see second "--", then we are also done parsing variables.
-          //
-          if (strcmp (s, "--") == 0)
-          {
-            var = false;
-            continue;
-          }
-
-          if (const char* p = strchr (s, '=')) // Covers =, +=, and =+.
-          {
-            // Diagnose the empty variable name situation. Note that we don't
-            // allow "partially broken down" assignments (as in foo =bar)
-            // since foo= bar would be ambigous.
-            //
-            if (p == s || (p == s + 1 && *s == '+'))
-              fail << "missing variable name in '" << s << "'";
-
-            r.cmd_vars.push_back (s);
-            continue;
-          }
-
-          // Handle the "broken down" variable assignments (i.e., foo = bar
-          // instead of foo=bar).
-          //
-          if (scan.more ())
-          {
-            const char* a (scan.peek ());
-
-            if (strcmp (a, "=" ) == 0 ||
-                strcmp (a, "+=") == 0 ||
-                strcmp (a, "=+") == 0)
-            {
-              string v (s);
-              v += a;
-
-              scan.next ();
-
-              if (scan.more ())
-                v += scan.next ();
-
-              r.cmd_vars.push_back (move (v));
-              continue;
-            }
-          }
-
-          // Fall through.
-        }
-
-        // Merge all the individual buildspec arguments into a single string.
-        // We use newlines to separate arguments so that line numbers in
-        // diagnostics signify argument numbers. Clever, huh?
-        //
-        if (argn != 0)
-          r.buildspec += '\n';
-
-        r.buildspec += s;
-
-        // See if we are using the shortcut syntax.
-        //
-        if (argn == 0 && r.buildspec.back () == ':')
-        {
-          r.buildspec.back () = '(';
-          shortcut = true;
-        }
-
-        argn++;
-      }
-
-      // Add the closing parenthesis unless there wasn't anything in between
-      // in which case pop the opening one.
-      //
-      if (shortcut)
-      {
-        if (argn == 1)
-          r.buildspec.pop_back ();
-        else
-          r.buildspec += ')';
-      }
-
-      // Get/set an environment variable tracing the operation.
-      //
-      auto get_env = [&verbosity, &trace] (const char* nm)
-      {
-        optional<string> r (getenv (nm));
-
-        if (verbosity () >= 5)
-        {
-          if (r)
-            trace << nm << ": '" << *r << "'";
-          else
-            trace << nm << ": <NULL>";
-        }
-
-        return r;
-      };
-
-      auto set_env = [&verbosity, &trace] (const char* nm, const string& vl)
-      {
-        try
-        {
-          if (verbosity () >= 5)
-            trace << "setting " << nm << "='" << vl << "'";
-
-          setenv (nm, vl);
-        }
-        catch (const system_error& e)
-        {
-          // The variable value can potentially be long/multi-line, so let's
-          // print it last.
-          //
-          fail << "unable to set environment variable " << nm << ": " << e <<
-            info << "value: '" << vl << "'";
-        }
-      };
-
-      // If the BUILD2_VAR_OVR environment variable is present, then parse its
-      // value as a newline-separated global variable overrides and prepend
-      // them to the overrides specified on the command line.
-      //
-      // Note that this means global overrides may not contain a newline.
-
-      // Verify that the string is a valid global override. Uses the file name
-      // and the options flag for diagnostics only.
-      //
-      auto verify_glb_ovr = [] (const string& v, const path_name& fn, bool opt)
-      {
-        size_t p (v.find ('=', 1));
-        if (p == string::npos || v[0] != '!')
-        {
-          diag_record dr (fail (fn));
-          dr << "expected " << (opt ? "option or " : "") << "global "
-             << "variable override instead of '" << v << "'";
-
-          if (p != string::npos)
-              dr << info << "prefix variable assignment with '!'";
-        }
-
-        if (p == 1 || (p == 2 && v[1] == '+')) // '!=' or '!+=' ?
-          fail (fn) << "missing variable name in '" << v << "'";
-      };
-
-      optional<string> env_ovr (get_env ("BUILD2_VAR_OVR"));
-      if (env_ovr)
-      {
-        path_name fn ("<BUILD2_VAR_OVR>");
-
-        auto i (r.cmd_vars.begin ());
-        for (size_t b (0), e (0); next_word (*env_ovr, b, e, '\n', '\r'); )
-        {
-          // Extract the override from the current line, stripping the leading
-          // and trailing spaces.
-          //
-          string s (*env_ovr, b, e - b);
-          trim (s);
-
-          // Verify and save the override, unless the line is empty.
-          //
-          if (!s.empty ())
-          {
-            verify_glb_ovr (s, fn, false /* opt */);
-            i = r.cmd_vars.insert (i, move (s)) + 1;
-          }
-        }
-      }
-
-      // Load the default options files, unless --no-default-options is
-      // specified on the command line or the BUILD2_DEF_OPT environment
-      // variable is set to a value other than 'true' or '1'.
-      //
-      // If loaded, prepend the default global overrides to the variables
-      // specified on the command line, unless BUILD2_VAR_OVR is set in which
-      // case just ignore them.
-      //
-      optional<string> env_def (get_env ("BUILD2_DEF_OPT"));
-
-      // False if --no-default-options is specified on the command line. Note
-      // that we cache the flag since it can be overridden by a default
-      // options file.
-      //
-      bool cmd_def (!ops.no_default_options ());
-
-      if (cmd_def && (!env_def || *env_def == "true" || *env_def == "1"))
-      try
-      {
-        optional<dir_path> extra;
-        if (ops.default_options_specified ())
-          extra = ops.default_options ();
-
-        // Load default options files.
-        //
-        default_options<options> def_ops (
-          load_default_options<options,
-                               cl::argv_file_scanner,
-                               cl::unknown_mode> (
-            nullopt /* sys_dir */,
-            path::home_directory (), // The home variable is not assigned yet.
-            extra,
-            default_options_files {{path ("b.options")},
-                                   nullopt /* start */},
-            [&trace, &verbosity] (const path& f, bool r, bool o)
-            {
-              if (verbosity () >= 3)
-              {
-                if (o)
-                  trace << "treating " << f << " as "
-                        << (r ? "remote" : "local");
-                else
-                  trace << "loading " << (r ? "remote " : "local ") << f;
-              }
-            },
-            "--options-file",
-            args_pos,
-            1024,
-            true /* args */));
-
-        // Merge the default and command line options.
-        //
-        ops = merge_default_options (def_ops, ops);
-
-        // Merge the default and command line global overrides, unless
-        // BUILD2_VAR_OVR is already set (in which case we assume this has
-        // already been done).
-        //
-        // Note that the "broken down" variable assignments occupying a single
-        // line are naturally supported.
-        //
-        if (!env_ovr)
-          r.cmd_vars =
-            merge_default_arguments (
-              def_ops,
-              r.cmd_vars,
-              [&verify_glb_ovr] (const default_options_entry<options>& e,
-                                 const strings&)
-              {
-                path_name fn (e.file);
-
-                // Verify that all arguments are global overrides.
-                //
-                for (const string& a: e.arguments)
-                  verify_glb_ovr (a, fn, true /* opt */);
-              });
-      }
-      catch (const invalid_argument& e)
-      {
-        fail << "unable to load default options files: " << e;
-      }
-      catch (const pair<path, system_error>& e)
-      {
-        fail << "unable to load default options files: " << e.first << ": "
-             << e.second;
-      }
-      catch (const system_error& e)
-      {
-        fail << "unable to obtain home directory: " << e;
-      }
-
-      // Verify and save the global overrides present in cmd_vars (default,
-      // from the command line, etc), if any, into the BUILD2_VAR_OVR
-      // environment variable.
-      //
-      if (!r.cmd_vars.empty ())
-      {
-        string ovr;
-        for (const string& v: r.cmd_vars)
-        {
-          if (v[0] == '!')
-          {
-            if (v.find_first_of ("\n\r") != string::npos)
-              fail << "newline in global variable override '" << v << "'";
-
-            if (!ovr.empty ())
-              ovr += '\n';
-
-            ovr += v;
-          }
-        }
-
-        // Optimize for the common case.
-        //
-        // Note: cmd_vars may contain non-global overrides.
-        //
-        if (!ovr.empty () && (!env_ovr || *env_ovr != ovr))
-          set_env ("BUILD2_VAR_OVR", ovr);
-      }
-
-      // Propagate disabling of the default options files to the potential
-      // nested invocations.
-      //
-      if (!cmd_def && (!env_def || *env_def != "0"))
-        set_env ("BUILD2_DEF_OPT", "0");
-
-      // Validate options.
-      //
-      if (ops.progress () && ops.no_progress ())
-        fail << "both --progress and --no-progress specified";
-
-      if (ops.mtime_check () && ops.no_mtime_check ())
-        fail << "both --mtime-check and --no-mtime-check specified";
-    }
-    catch (const cl::exception& e)
-    {
-      fail << e;
-    }
-
-    r.verbosity = verbosity ();
-
-    if (ops.silent () && r.verbosity != 0)
-      fail << "specified with -v, -V, or --verbose verbosity level "
-           << r.verbosity << " is incompatible with --silent";
-
-    return r;
-  }
-
   int
   main (int argc, char* argv[]);