aboutsummaryrefslogtreecommitdiff
path: root/libbuild2/build/script/parser.cxx
diff options
context:
space:
mode:
Diffstat (limited to 'libbuild2/build/script/parser.cxx')
-rw-r--r--libbuild2/build/script/parser.cxx201
1 files changed, 148 insertions, 53 deletions
diff --git a/libbuild2/build/script/parser.cxx b/libbuild2/build/script/parser.cxx
index bcea7e0..035ab6b 100644
--- a/libbuild2/build/script/parser.cxx
+++ b/libbuild2/build/script/parser.cxx
@@ -205,10 +205,11 @@ namespace build2
// enter: next token is peeked at (type in tt)
// leave: newline
- assert (!fct ||
- *fct == line_type::cmd_if ||
- *fct == line_type::cmd_while ||
- *fct == line_type::cmd_for);
+ assert (!fct ||
+ *fct == line_type::cmd_if ||
+ *fct == line_type::cmd_while ||
+ *fct == line_type::cmd_for_stream ||
+ *fct == line_type::cmd_for_args);
// Determine the line type/start token.
//
@@ -246,50 +247,107 @@ namespace build2
break;
}
- case line_type::cmd_for:
+ //
+ // See pre_parse_line_start() for details.
+ //
+ case line_type::cmd_for_args: assert (false); break;
+ case line_type::cmd_for_stream:
{
- // First take care of the variable name.
+ // First we need to sense the next few tokens and detect which
+ // form of the loop we are dealing with, the first (for x: ...)
+ // or the third (x <...) one. Note that the second form (... | for
+ // x) is handled separately.
+ //
+ // @@ Do we diagnose `... | for x: ...`?
+ //
+ // If the next token doesn't introduce a variable (doesn't start
+ // attributes and doesn't look like a variable name), then this is
+ // the third form. Otherwise, if colon follows the variable name,
+ // then this is the first form and the third form otherwise.
+ //
+ // Note that for the third form we will need to pass the 'for'
+ // token as a program name to the command expression parsing
+ // function since it will be gone from the token stream by that
+ // time. Thus, we save it.
//
- mode (lexer_mode::normal);
+ // Note also that in this model it won't be possible to support
+ // options in the first form.
+ //
+ token pt (t);
+ assert (pt.type == type::word && pt.value == "for");
+ mode (lexer_mode::for_loop);
next_with_attributes (t, tt);
- attributes_push (t, tt);
- if (tt != type::word || t.qtype != quote_type::unquoted)
- fail (t) << "expected variable name instead of " << t;
+ // Note that we also consider special variable names (those that
+ // don't clash with the command line elements like redirects, etc)
+ // to later fail gracefully.
+ //
+ string& n (t.value);
- const string& n (t.value);
+ if (tt == type::lsbrace || // Attributes.
+ (tt == type::word && // Variable name.
+ t.qtype == quote_type::unquoted &&
+ (n[0] == '_' || alpha (n[0]) || n == "~")))
+ {
+ attributes_push (t, tt);
- if (special_variable (n))
- fail (t) << "attempt to set '" << n << "' variable directly";
+ if (tt != type::word || t.qtype != quote_type::unquoted)
+ fail (t) << "expected variable name instead of " << t;
- // We don't pre-enter variables.
- //
- ln.var = nullptr;
+ if (special_variable (n))
+ fail (t) << "attempt to set '" << n << "' special variable";
- next (t, tt);
+ if (lexer_->peek_char ().first == ':')
+ lt = line_type::cmd_for_args;
+ }
- if (tt != type::colon)
+ if (lt == line_type::cmd_for_stream) // for x <...
{
- // @@ TMP We will need to fallback to parsing the 'for x <...'
- // form instead.
+ // At this point `t` contains the token that follows the `for`
+ // token and, potentially, the attributes. Now pre-parse the
+ // command expression in the command_line lexer mode starting
+ // from this position and also passing the 'for' token as a
+ // program name.
//
- fail (t) << "expected ':' instead of " << t
- << " after variable name";
+ // Note that the fact that the potential attributes are already
+ // parsed doesn't affect the command expression pre-parsing.
+ // Also note that they will be available during the execution
+ // phase being replayed.
+ //
+ expire_mode (); // Expire the for-loop lexer mode.
+
+ parse_command_expr_result r (
+ parse_command_expr (t, tt,
+ lexer::redirect_aliases,
+ move (pt)));
+
+ assert (r.for_loop);
+
+ if (tt != type::newline)
+ fail (t) << "expected newline instead of " << t;
+
+ parse_here_documents (t, tt, r);
}
+ else // for x: ...
+ {
+ next (t, tt);
- expire_mode (); // Expire the normal lexer mode.
+ assert (tt == type::colon);
- // Parse the value similar to the var line type (see above).
- //
- mode (lexer_mode::variable_line);
- parse_variable_line (t, tt);
+ expire_mode (); // Expire the for-loop lexer mode.
- if (tt != type::newline)
- fail (t) << "expected newline instead of " << t << " after for";
+ // Parse the value similar to the var line type (see above).
+ //
+ mode (lexer_mode::variable_line);
+ parse_variable_line (t, tt);
- ++level_;
+ if (tt != type::newline)
+ fail (t) << "expected newline instead of " << t << " after for";
+ }
+ ln.var = nullptr;
+ ++level_;
break;
}
case line_type::cmd_elif:
@@ -321,15 +379,24 @@ namespace build2
// Fall through.
case line_type::cmd:
{
- pair<command_expr, here_docs> p;
+ parse_command_expr_result r;
if (lt != line_type::cmd_else && lt != line_type::cmd_end)
- p = parse_command_expr (t, tt, lexer::redirect_aliases);
+ r = parse_command_expr (t, tt, lexer::redirect_aliases);
+
+ if (r.for_loop)
+ {
+ lt = line_type::cmd_for_stream;
+ ln.var = nullptr;
+
+ ++level_;
+ }
if (tt != type::newline)
fail (t) << "expected newline instead of " << t;
- parse_here_documents (t, tt, p);
+ parse_here_documents (t, tt, r);
+
break;
}
}
@@ -358,7 +425,8 @@ namespace build2
break;
}
case line_type::cmd_while:
- case line_type::cmd_for:
+ case line_type::cmd_for_stream:
+ case line_type::cmd_for_args:
{
tt = peek (lexer_mode::first_token);
@@ -396,7 +464,8 @@ namespace build2
break;
}
case line_type::cmd_while:
- case line_type::cmd_for:
+ case line_type::cmd_for_stream:
+ case line_type::cmd_for_args:
{
fct = bt;
break;
@@ -466,7 +535,9 @@ namespace build2
// enter: peeked first token of next line (type in tt)
// leave: newline
- assert (lt == line_type::cmd_while || lt == line_type::cmd_for);
+ assert (lt == line_type::cmd_while ||
+ lt == line_type::cmd_for_stream ||
+ lt == line_type::cmd_for_args);
// Parse lines until we see closing 'end'.
//
@@ -491,12 +562,12 @@ namespace build2
//
assert (!pre_parse_);
- pair<command_expr, here_docs> p (
+ parse_command_expr_result pr (
parse_command_expr (t, tt, lexer::redirect_aliases));
assert (tt == type::newline);
- parse_here_documents (t, tt, p);
+ parse_here_documents (t, tt, pr);
assert (tt == type::newline);
// @@ Note that currently running programs via a runner (e.g., see
@@ -509,7 +580,7 @@ namespace build2
// passed to the environment constructor, similar to passing the
// script deadline.
//
- return move (p.first);
+ return move (pr.expr);
}
//
@@ -1121,6 +1192,7 @@ namespace build2
auto exec_cmd = [this] (token& t, build2::script::token_type& tt,
const iteration_index* ii, size_t li,
bool single,
+ const function<command_function>& cf,
const location& ll)
{
// We use the 0 index to signal that this is the only command.
@@ -1131,7 +1203,7 @@ namespace build2
command_expr ce (
parse_command_line (t, static_cast<token_type&> (tt)));
- runner_->run (*environment_, ce, ii, li, ll);
+ runner_->run (*environment_, ce, ii, li, cf, ll);
};
exec_lines (s.body, exec_cmd);
@@ -1184,6 +1256,7 @@ namespace build2
build2::script::token_type& tt,
const iteration_index* ii, size_t li,
bool /* single */,
+ const function<command_function>& cf,
const location& ll)
{
// Note that we never reset the line index to zero (as we do in
@@ -1282,14 +1355,17 @@ namespace build2
command_expr ce (
parse_command_line (t, static_cast<token_type&> (tt)));
- // Verify that this expression executes the set builtin.
+ // Verify that this expression executes the set builtin or is a
+ // for-loop.
//
if (find_if (ce.begin (), ce.end (),
- [] (const expr_term& et)
+ [&cf] (const expr_term& et)
{
const process_path& p (et.pipe.back ().program);
return p.initial == nullptr &&
- p.recall.string () == "set";
+ (p.recall.string () == "set" ||
+ (cf != nullptr &&
+ p.recall.string () == "for"));
}) == ce.end ())
{
const replay_tokens& rt (data.scr.depdb_preamble.back ().tokens);
@@ -1301,7 +1377,7 @@ namespace build2
info (rt[0].location ()) << "depdb preamble ends here";
}
- runner_->run (*environment_, ce, ii, li, ll);
+ runner_->run (*environment_, ce, ii, li, cf, ll);
}
};
@@ -2336,18 +2412,36 @@ namespace build2
{
// Note: depdb is disallowed inside flow control constructs.
//
- string s;
- build2::script::run (*environment_,
- cmd,
- nullptr /* iteration_index */, li,
- ll,
- !file ? &s : nullptr);
-
if (!file)
{
- iss.str (move (s));
+ function<command_function> cf (
+ [&iss]
+ (build2::script::environment&,
+ const strings&,
+ auto_fd in,
+ bool pipe,
+ const optional<deadline>& dl,
+ const command& deadline_cmd,
+ const location& ll)
+ {
+ iss.str (stream_read (move (in),
+ pipe,
+ dl,
+ deadline_cmd,
+ ll));
+ });
+
+ build2::script::run (*environment_,
+ cmd,
+ nullptr /* iteration_index */, li,
+ ll,
+ cf, false /* last_cmd */);
+
iss.exceptions (istream::badbit);
}
+ else
+ build2::script::run (
+ *environment_, cmd, nullptr /* iteration_index */, li, ll);
}
ifdstream ifs (ifdstream::badbit);
@@ -2490,7 +2584,8 @@ namespace build2
environment_->set_special_variables (a);
}
- // When add a special variable don't forget to update lexer::word().
+ // When add a special variable don't forget to update lexer::word() and
+ // for-loop parsing in pre_parse_line().
//
bool parser::
special_variable (const string& n) noexcept