clean up cmakefile a little bit more.

commit f0944a89f27e44b1764988806e655f09764e80df
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Tue Aug 30 12:24:08 2016 -0400

    exit throws execution of input error w/ possible 0 value.  catch it.

commit 9e7f9c1ae049aa26513413f4767268b47ee22e98
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Tue Aug 30 12:23:21 2016 -0400

    builtins - more consistent argument handling.

commit be4c1c902f5a3a3f01e92ae52c7d6cc5d8731b65
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Tue Aug 30 12:23:01 2016 -0400

    .

commit 68d0c29fec112c6e7bc3a672b41eb7eb758a8941
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Tue Aug 30 12:22:51 2016 -0400

    exit command.

commit 25b0a7f7da9220b03026123bb5072c2da1d73fde
Author: Kelvin Sherlock <ksherlock@gmail.com>
Date:   Tue Aug 30 12:21:16 2016 -0400

    builtin quit command.

CMakeLists.txt

@@ -1,25 +1,50 @@
 
 # CMAKE_INSTALL_PREFIX defaults to /usr/local.
 
-cmake_minimum_required(VERSION 2.6)
+cmake_minimum_required(VERSION 3.1)
 project("mpw-shell")
 set (PROJECT_TYPE "CXX")
 set (PROJECT_NAME "MPW Shell")
 
-set(CMAKE_CXX_FLAGS "-g -Wall -Wno-unused-variable -Wno-multichar -O1")
+
+# -std=c++14
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD_REQUIRED TRUE)
+set(CMAKE_CXX_EXTENSIONS FALSE)
+
+
+#
+# build config.h
+#
+
+INCLUDE (CheckFunctionExists)
+INCLUDE (CheckLibraryExists)
+
+SET(CMAKE_EXTRA_INCLUDE_FILES stdio.h)
+CHECK_FUNCTION_EXISTS(dprintf HAVE_DPRINTF)
+SET(CMAKE_EXTRA_INCLUDE_FILES)
+
+CHECK_LIBRARY_EXISTS(edit readline "" HAVE_LIBEDIT)
+CHECK_LIBRARY_EXISTS(readline readline "" HAVE_LIBREADLINE)
+CHECK_LIBRARY_EXISTS(history add_history "" HAVE_LIBHISTORY)
+
+CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/config.h.in ${CMAKE_CURRENT_BINARY_DIR}/config.h)
+
+
+add_compile_options(-g -Wall -Wno-unused-variable -Wno-multichar -O1)
 
 if(${CMAKE_CXX_COMPILER_ID} MATCHES "Clang")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-const-variable ")
+	add_compile_options(-Wno-unused-const-variable)
 endif()
 
 
 if(${CMAKE_CXX_COMPILER_ID} MATCHES "GNU")
-	set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -Wno-unused-but-set-variable")
+	add_compile_options(-Wno-unused-but-set-variable)
 endif()
 
 
-
-add_definitions(-I ${CMAKE_SOURCE_DIR}/ -I ${CMAKE_CURRENT_BINARY_DIR}/ )
+include_directories(${CMAKE_SOURCE_DIR})
+include_directories(${CMAKE_CURRENT_BINARY_DIR})
 
 # from https://github.com/gsauthof/cmake-ragel
 macro(RAGEL_TARGET Name Input Output)
@@ -65,17 +90,17 @@ RAGEL_TARGET(value value.rl value.cpp COMPILE_FLAGS "-p -G2")
 
 # need to copy all OUTPUT file to the build dir
 add_custom_command(
-	OUTPUT phase2-parser.cpp phase2-parser.h phase2-parser.out
-	COMMAND lemon++ phase2-parser.lemon
-	COMMAND mv -f phase2-parser.cpp phase2-parser.h phase2-parser.out ${CMAKE_CURRENT_BINARY_DIR}/
-	MAIN_DEPENDENCY phase2-parser.lemon 
+	OUTPUT phase3.cpp phase3.h phase3.out
+	COMMAND lemon++ phase3.lemon
+	COMMAND mv -f phase3.cpp phase3.h phase3.out ${CMAKE_CURRENT_BINARY_DIR}/
+	MAIN_DEPENDENCY phase3.lemon 
 	WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
 )
 
 
 add_executable(mpw-shell mpw-shell.cpp  mpw-shell-token.cpp mpw-shell-expand.cpp 
-	mpw-shell-parser.cpp value.cpp mpw-shell-quote.cpp 
-	phase1.cpp phase2.cpp phase2-parser.cpp command.cpp environment.cpp builtins.cpp 
+	mpw-shell-parser.cpp mpw_parser.cpp value.cpp mpw-shell-quote.cpp 
+	phase1.cpp phase2.cpp phase3.cpp command.cpp environment.cpp builtins.cpp 
 	pathnames.cpp
 	macroman.cpp
 	cxx/mapped_file.cpp
@@ -84,12 +109,19 @@ add_executable(mpw-shell mpw-shell.cpp  mpw-shell-token.cpp mpw-shell-expand.cpp
 	cxx/directory_iterator.cpp
 )
 
+#
+# -ledit includes history stuff.  gnu -lreadline does not.
+#
+if(HAVE_LIBEDIT)
 	target_link_libraries(mpw-shell edit)
+elseif(HAVE_LIBREADLINE)
+	target_link_libraries(mpw-shell readline)
+	if (HAVE_LIBHISTORY)
+		target_link_libraries(mpw-shell history)
+	endif()
+endif()
+
 
-# all this for -std=c++14
-set_property (TARGET mpw-shell PROPERTY CXX_STANDARD 14)
-set_property (TARGET mpw-shell PROPERTY CXX_STANDARD_REQUIRED TRUE)
-set_property (TARGET mpw-shell PROPERTY CXX_EXTENSIONS FALSE)
 
 # create a symlink for mpw-make
 add_custom_command(

README.md

@@ -11,16 +11,17 @@ Supported features
 * Begin ... End
 * Loop ... End
 * For name In [word...] ... End
-* Break [If], Continue [If]
+* Break [If], Continue [If], Exit [If]
 * ( ... )
 * ||
 * &&
-* redirection
+* Redirection
 * | "pipes" (via a temporary file. Presumably, that's what MPW did as well.)
+* Subshells (`...`, ``...``)
+
 
 Not (yet) supported
 -------------
-* subshells (`...`, ``...``)
 * aliases
 * regular expressions
 * text-editing commands (search forward/backward, et cetera)
@@ -33,9 +34,11 @@ Builtin Commands
 * Directory
 * Echo
 * Evaluate
+* Execute
 * Exists
 * Export
 * Parameters
+* Quit
 * Quote
 * Set
 * Shift
@@ -49,7 +52,18 @@ Builtin Commands
 Setup
 -----
 1. Install MPW.  The mpw binary should be somewhere in your `$PATH`.
-It also checks `/usr/local/bin/mpw` and `$HOME/mpw/bin/mpw`
+It also checks `/usr/local/bin/mpw` and `$HOME/mpw/bin/mpw`.  You can
+use mpw-shell without it but only with builtin commands.
 2. Copy the `Startup` script to `$HOME/mpw/`.  This script is executed
 when mpw-shell (or mpw-make) starts up (imagine that) and should
 be used to set environment variables.
+
+
+Command Line Flags
+------------------
+
+    -D name=value  Define environment variable
+    -v             Be verbose (equivalent to -Decho=1)
+    -f             Ignore the Startup script
+    -c string      Execute string
+    -h             Display help

builtins.cpp

@@ -4,6 +4,7 @@
 #include "fdset.h"
 #include "value.h"
 #include "environment.h"
+#include "error.h"
 
 #include <string>
 #include <vector>
@@ -25,6 +26,7 @@
 #include <fcntl.h>
 
 #include "version.h"
+#include "config.h"
 
 namespace ToolBox {
 	std::string MacToUnix(const std::string path);
@@ -114,16 +116,23 @@ namespace {
 #define fputc DO_NOT_USE_FPUTC
 
 inline int fdputs(const char *data, int fd) {
-	auto rv = write(fd, data, strlen(data));  return rv < 0 ? EOF : rv;
+	auto rv = write(fd, data, strlen(data));
+	return rv < 0 ? EOF : rv;
+}
+
+inline int fdputs(const std::string &s, int fd) {
+	auto rv = write(fd, s.data(), s.size());
+	return rv < 0 ? EOF : rv;
 }
 
 inline int fdputc(int c, int fd) {
 	unsigned char tmp = c;
-	auto rv = write(fd, &tmp, 1);  return rv < 0 ? EOF : c;
+	auto rv = write(fd, &tmp, 1);
+	return rv < 0 ? EOF : c;
 }
 
 #ifdef HAVE_DPRINTF
-#define fdprintf(...) dprintf(__VA_ARGS__)
+#define fdprintf dprintf
 #else
 inline int fdprintf(int fd, const char *format, ...) {
 	char *cp = nullptr;
@@ -271,22 +280,14 @@ static int export_common(Environment &env, bool export_or_unexport, const std::v
 
 	const char *name = export_or_unexport ? "Export" : "Unexport";
 
-	struct {
-		int _r = 0;
-		int _s = 0;
-	} flags;
+	bool _r = false;
+	bool _s = false;
 	bool error = false;
 
-	std::vector<std::string> argv = getopt(tokens, [&](char c){
-		switch(c) {
-			case 'r':
-			case 'R':
-				flags._r = true;
-				break;
-			case 's':
-			case 'S':
-				flags._s = true;
-				break;
+	auto argv = getopt(tokens, [&](char c){
+		switch(tolower(c)) {
+			case 'r': _r = true; break;
+			case 's': _s = true; break;
 			default:
 				fdprintf(stderr, "### %s - \"-%c\" is not an option.\n", name, c);
 				error = true;
@@ -300,7 +301,7 @@ static int export_common(Environment &env, bool export_or_unexport, const std::v
 	}
 
 	if (argv.empty()) {
-		if (flags._r && flags._s) goto conflict;
+		if (_r && _s) goto conflict;
 
 		// list of exported vars.
 		// -r will generate unexport commands for exported variables.
@@ -312,14 +313,14 @@ static int export_common(Environment &env, bool export_or_unexport, const std::v
 		for (const auto &kv : env) {
 			const std::string& vname = kv.first;
 			if (kv.second == export_or_unexport)
-				fdprintf(stdout, "%s%s\n", flags._s ? "" : name, quote(vname).c_str());
+				fdprintf(stdout, "%s%s\n", _s ? "" : name, quote(vname).c_str());
 		}
 		return 0;
 	}
 	else {
 		// mark as exported.
 
-		if (flags._r || flags._s) goto conflict;
+		if (_r || _s) goto conflict;
 
 		for (std::string s : argv) {
 			auto iter = env.find(s);
@@ -501,12 +502,9 @@ int builtin_directory(Environment &env, const std::vector<std::string> &tokens,
 	bool error = false;
 
 	std::vector<std::string> argv = getopt(tokens, [&](char c){
-		switch(c)
+		switch(tolower(c))
 		{
-			case 'q':
-			case 'Q':
-				q = true;
-				break;
+			case 'q': q = true; break;
 			default:
 				fdprintf(stderr, "### Directory - \"-%c\" is not an option.\n", c);
 				error = true;
@@ -577,24 +575,12 @@ int builtin_exists(Environment &env, const std::vector<std::string> &tokens, con
 	std::vector<std::string> argv = getopt(tokens, [&](char c){
 		switch(tolower(c))
 		{
-			case 'a':
-				_a = true;
-				break;
-			case 'd':
-				_d = true;
-				break;
-			case 'f':
-				_f = true;
-				break;
-			case 'n':
-				_n = true;
-				break;
-			case 'q':
-				_q = true;
-				break;
-			case 'w':
-				_w = true;
-				break;
+			case 'a': _a = true; break;
+			case 'd': _d = true; break;
+			case 'f': _f = true; break;
+			case 'n': _n = true; break;
+			case 'q': _q = true; break;
+			case 'w': _w = true; break;
 			default:
 				fdprintf(stderr, "### Exists - \"-%c\" is not an option.\n", c);
 				error = true;
@@ -765,15 +751,15 @@ int builtin_evaluate(Environment &env, std::vector<token> &&tokens, const fdmask
 int builtin_which(Environment &env, const std::vector<std::string> &tokens, const fdmask &fds) {
 
 	// which [-a] [-p] [command]
-	bool a = false;
-	bool p = false;
+	bool _a = false;
+	bool _p = false;
 	bool error = false;
 
 	std::vector<std::string> argv = getopt(tokens, [&](char c){
-		switch(c)
+		switch(tolower(c))
 		{
-			case 'a': case 'A': a = true; break;
-			case 'p': case 'P': p = true; break;
+			case 'a': _a = true; break;
+			case 'p': _p = true; break;
 
 			default:
 				fdprintf(stderr, "### Which - \"-%c\" is not an option.\n", c);
@@ -824,7 +810,7 @@ int builtin_which(Environment &env, const std::vector<std::string> &tokens, cons
 	}
 
 	for(; ss; ++ss) {
-		if (p) fdprintf(stderr, "checking %s\n", ss->c_str());
+		if (_p) fdprintf(stderr, "checking %s\n", ss->c_str());
 
 		std::error_code ec;
 		fs::path p(ToolBox::MacToUnix(ss->c_str()));
@@ -833,13 +819,13 @@ int builtin_which(Environment &env, const std::vector<std::string> &tokens, cons
 		if (fs::exists(p, ec)) {
 			found = true;
 			fdprintf(stdout, "%s\n", quote(p).c_str());
-			if (!a) break;
+			if (!_a) break;
 		}
 
 	}
 
 	// check builtins...
-	if (!found || a) {
+	if (!found || _a) {
 
 		static const char *builtins[] = {
 			"aboutbox",
@@ -847,12 +833,15 @@ int builtin_which(Environment &env, const std::vector<std::string> &tokens, cons
 			"catenate",
 			"directory",
 			"echo",
+			"execute",
 			"exists",
 			"export",
+			"false", // not in MPW
 			"parameters",
 			"quote",
 			"set",
 			"shift",
+			"true", // not in MPW
 			"unalias",
 			"unexport",
 			"unset",
@@ -940,9 +929,7 @@ int builtin_version(Environment &env, const std::vector<std::string> &tokens, co
 	auto argv = getopt(tokens, [&](char c){
 		switch(tolower(c))
 		{
-			case 'v':
-				_v = true;
-				break;
+			case 'v': _v = true; break;
 			default:
 				fdprintf(stderr, "### Version - \"-%c\" is not an option.\n", c);
 				error = true;
@@ -1026,3 +1013,63 @@ int builtin_true(Environment &, const std::vector<std::string> &, const fdmask &
 int builtin_false(Environment &, const std::vector<std::string> &, const fdmask &) {
 	return 1;
 }
+
+
+int builtin_quit(Environment &, const std::vector<std::string> &tokens, const fdmask &fds) {
+
+	bool error = false;
+	bool _y = false;
+	bool _n = false;
+	bool _c = false;
+
+	auto argv = getopt(tokens, [&](char c){
+		switch(tolower(c))
+		{
+			case 'c': _c = true; break;
+			case 'n': _n = true; break;
+			case 'y': _y = true; break;
+
+			default:
+				fdprintf(stderr, "### Quit - \"-%c\" is not an option.\n", c);
+				error = true;
+				break;
+		}
+	});
+	if (_y + _n + _c > 1) {
+		fdprintf(stderr, "### Quit - Conflicting options were specified.\n");
+		error = true;		
+	}
+
+	if (argv.size() > 0) {
+		fdprintf(stderr, "### Quit - Too many parameters were specified.\n");
+		error = true;
+	}
+
+	if (error) {
+		fdprintf(stderr, "# Usage - Quit [-y | -n | -c]\n");
+		return 1;
+	}
+
+	throw quit_command_t{};
+	return 0;
+}
+
+
+int builtin_execute(Environment &e, const std::vector<std::string> &tokens, const fdmask &fds) {
+
+	// runs argv[1] in the current environment. unlike MPW, argv[1] must be a script.
+	// special enhancement -- '-' means execute stdin.
+
+	if (tokens.size() < 2) return 0;
+	std::string filename = tokens[1];
+	if (filename == "-") {
+		// since we're parsing stdin, don't let any children read it. [???]
+		fdset new_fds;
+		int fd = open("/dev/null", O_RDONLY);
+		new_fds.set(0, fd);
+
+		return read_fd(e, fds[0], new_fds | fds);
+	}
+
+	return read_file(e, filename, fds);
+}

builtins.h

@@ -25,6 +25,12 @@ int builtin_which(Environment &e, const std::vector<std::string> &, const fdmask
 int builtin_alias(Environment &e, const std::vector<std::string> &, const fdmask &);
 int builtin_unalias(Environment &e, const std::vector<std::string> &, const fdmask &);
 
+int builtin_execute(Environment &e, const std::vector<std::string> &, const fdmask &);
+int builtin_true(Environment &e, const std::vector<std::string> &, const fdmask &);
+int builtin_false(Environment &e, const std::vector<std::string> &, const fdmask &);
+int builtin_quit(Environment &e, const std::vector<std::string> &, const fdmask &);
+
+
 int builtin_evaluate(Environment &e, std::vector<token> &&, const fdmask &);
 
 #endif

command.cpp

@@ -1,10 +1,11 @@
 #include "command.h"
-#include "phase2-parser.h"
+#include "phase3.h"
 #include "environment.h"
 #include "fdset.h"
 #include "builtins.h"
 #include "mpw-shell.h"
 #include "error.h"
+#include "value.h"
 
 #include <stdexcept>
 #include <unordered_map>
@@ -17,6 +18,7 @@
 #include "cxx/filesystem.h"
 #include "cxx/string_splitter.h"
 
+
 #include <strings.h>
 #include <unistd.h>
 #include <sys/wait.h>
@@ -40,8 +42,7 @@ typedef std::vector<token> token_vector;
 
 namespace {
 
-	struct break_command_t {};
-	struct continue_command_t {};
+
 
 	/*
 	 * returns:
@@ -56,6 +57,12 @@ namespace {
 		return -3;
 	}
 
+	int bad_exit() {
+		fprintf(stderr, "### Exit - Missing if keyword.\n");
+		fprintf(stderr, "# Usage - Exit [Number] [if expression...]\n");
+		return -3;
+	}
+
 	int evaluate(int type, token_vector &&tokens, Environment &env) {
 		std::reverse(tokens.begin(), tokens.end());
 
@@ -64,6 +71,8 @@ namespace {
 		switch(type) {
 			default: return 0;
 
+					// exit [number] [if expr] ([number has been removed])
+			case EXIT:
 			case BREAK:
 			case CONTINUE:
 			case ELSE:
@@ -77,10 +86,12 @@ namespace {
 						case BREAK: name = "Break"; break;
 						case CONTINUE: name = "Continue"; break;
 						case ELSE: name = "Else"; break;
+						case EXIT: name = "Exit"; return bad_exit(); break;
 					}
 					return bad_if(name);
 				}
 				// fall through.
+
 			case IF:
 				tokens.pop_back();
 				try {
@@ -198,9 +209,11 @@ namespace {
 		{"catenate", builtin_catenate},
 		{"directory", builtin_directory},
 		{"echo", builtin_echo},
+		{"execute", builtin_execute},
 		{"exists", builtin_exists},
 		{"export", builtin_export},
 		{"parameters", builtin_parameters},
+		{"quit", builtin_quit},
 		{"quote", builtin_quote},
 		{"set", builtin_set},
 		{"shift", builtin_shift},
@@ -209,6 +222,10 @@ namespace {
 		{"unset", builtin_unset},
 		{"version", builtin_version},
 		{"which", builtin_which},
+
+		// not in MPW.
+		{"true", builtin_true},
+		{"false", builtin_false},
 	};
 
 
@@ -278,9 +295,6 @@ namespace {
 }
 
 
-
-//std::string expand_vars(const std::string &s, const class Environment &);
-
 command::~command()
 {}
 
@@ -293,7 +307,7 @@ command::~command()
 
 
 template<class F>
-int exec(std::string command, Environment &env, bool throwup, F &&fx) {
+int exec(std::string command, Environment &env, const fdmask &fds, bool throwup, F &&fx) {
 
 	bool echo = true;
 	int rv = 0;
@@ -302,7 +316,7 @@ int exec(std::string command, Environment &env, bool throwup, F &&fx) {
 
 	try {
 		process p;
-		command = expand_vars(command, env);
+		command = expand_vars(command, env, fds);
 		auto tokens = tokenize(command, false);
 		if (tokens.empty()) return 0;
 		parse_tokens(std::move(tokens), p);
@@ -330,7 +344,7 @@ int exec(std::string command, Environment &env, bool throwup, F &&fx) {
 int simple_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
 
-	return exec(text, env, throwup, [&](process &p){
+	return exec(text, env, fds, throwup, [&](process &p){
 
 		fdmask newfds = p.fds | fds;
 
@@ -367,7 +381,7 @@ int simple_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 }
 
 template<class F>
-int eval_exec(std::string command, Environment &env, bool throwup, F &&fx){
+int eval_exec(std::string command, Environment &env, const fdmask &fds, bool throwup, F &&fx){
 
 	std::string name;
 	bool echo = true;
@@ -376,7 +390,7 @@ int eval_exec(std::string command, Environment &env, bool throwup, F &&fx){
 	if (control_c) throw execution_of_input_terminated();
 
 	try {
-		command = expand_vars(command, env);
+		command = expand_vars(command, env, fds);
 		auto tokens = tokenize(command, true);
 
 		if (tokens.empty()) return 0;
@@ -386,6 +400,10 @@ int eval_exec(std::string command, Environment &env, bool throwup, F &&fx){
 
 		rv = fx(tokens);
 	}
+	catch (const exit_command_t &ex) {
+		// convert to execution of input terminated.
+		throw execution_of_input_terminated(ex.value);
+	}
 
 	catch (mpw_error &e) {
 		if (echo) env.echo("%s", command.c_str());
@@ -406,29 +424,8 @@ int eval_exec(std::string command, Environment &env, bool throwup, F &&fx){
 
 int evaluate_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-#if 0
-	if (control_c) throw execution_of_input_terminated();
 
-	std::string s = expand_vars(text, env);
-
-	env.set("command", "evaluate");
-
-	env.echo("%s", s.c_str());
-
-	try {
-		auto tokens = tokenize(s, true);
-		if (tokens.empty()) return 0;
-
-		int status = builtin_evaluate(env, std::move(tokens), fds);
-
-		return env.status(status, throwup);
-	} catch (std::exception &e) {
-		fprintf(stderr, "%s\n", e.what());
-		return env.status(1, throwup);
-	}
-#endif
-
-	return eval_exec(text, env, throwup, [&](token_vector &tokens){
+	return eval_exec(text, env, fds, throwup, [&](token_vector &tokens){
 		env.set("command", "evaluate");
 		return builtin_evaluate(env, std::move(tokens), fds);
 	});
@@ -439,7 +436,7 @@ int evaluate_command::execute(Environment &env, const fdmask &fds, bool throwup)
 
 int break_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-	return eval_exec(text, env, throwup, [&](token_vector &tokens){
+	return eval_exec(text, env, fds, throwup, [&](token_vector &tokens){
 		env.set("command", "break");
 		if (!env.loop()) throw break_error();
 		int status = evaluate(BREAK, std::move(tokens), env);
@@ -447,30 +444,11 @@ int break_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 		return status;
 	});
 
-#if 0
-	if (control_c) throw execution_of_input_terminated();
-
-	std::string s = expand_vars(text, env);
-
-	env.set("command", "break");
-
-	env.echo("%s", s.c_str());
-	if (!env.loop()) {
-		fputs("### MPW Shell - Break must be within for or loop.\n", stderr);
-		return env.status(-3, throwup);
-	}
-
-	// check/evaluate if clause.
-	int status = evaluate(BREAK, s, env);
-	if (status > 0)
-		throw break_command_t();
-	return env.status(status, throwup);
-#endif
 }
 
 int continue_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-	return eval_exec(text, env, throwup, [&](token_vector &tokens){
+	return eval_exec(text, env, fds, throwup, [&](token_vector &tokens){
 		env.set("command", "continue");
 		if (!env.loop()) throw continue_error();
 		int status = evaluate(CONTINUE, std::move(tokens), env);
@@ -478,26 +456,39 @@ int continue_command::execute(Environment &env, const fdmask &fds, bool throwup)
 		return status;
 	});
 
-#if 0
-	if (control_c) throw execution_of_input_terminated();
-
-	std::string s = expand_vars(text, env);
-
-	env.set("command", "continue");
-
-	env.echo("%s", s.c_str());
-	if (!env.loop()) {
-		fputs("### MPW Shell - Continue must be within for or loop.\n", stderr);
-		return env.status(-3, throwup);
 }
 
 
-	// check/evaluate if clause.
-	int status = evaluate(CONTINUE, s, env);
-	if (status > 0)
-		throw continue_command_t();
-	return env.status(status, throwup);
-#endif
+int exit_command::execute(Environment &env, const fdmask &fds, bool throwup) {
+
+	// exit
+	// exit [number] [if expr ]]
+	// todo -- 
+
+	return eval_exec(text, env, fds, throwup, [&](token_vector &tokens){
+		env.set("command", "exit");
+		env.status(0);
+
+		if (tokens.size() <= 1) {
+			throw exit_command_t{};
+		}
+
+
+		int status = 0;
+		value v(tokens[1]);
+		// remove the return value to make processing easier.
+		if (v.is_number()) {
+			tokens.erase(tokens.begin() + 1);
+		}
+		status = evaluate(EXIT, std::move(tokens), env);
+
+		if (status) {
+			int ok = v.to_number(0);
+			throw exit_command_t{ok};
+		}
+
+		return 0;
+	});
 }
 
 int or_command::execute(Environment &e, const fdmask &fds, bool throwup) {
@@ -550,8 +541,9 @@ int pipe_command::execute(Environment &e, const fdmask &fds, bool throwup) {
 		lseek(fd, 0, SEEK_SET);
 
 		rv = children[1]->execute(e, pipe_fd | fds, throwup);
-
+		return e.status(rv, throwup);
 	}
+
 	if (children[0]) return children[0]->execute(e, fds, throwup);
 	if (children[1]) return children[1]->execute(e, fds, throwup);
 	return e.status(0, throwup);
@@ -576,7 +568,7 @@ int error_command::execute(Environment &e, const fdmask &fds, bool throwup) {
 		return e.status(-3);
 	}
 
-	std::string s = expand_vars(text, e);
+	std::string s = expand_vars(text, e, fds);
 
 	e.echo("%s", s.c_str());
 
@@ -600,7 +592,7 @@ int error_command::execute(Environment &e, const fdmask &fds, bool throwup) {
 }
 
 template<class F>
-int begin_end_exec(std::string begin, std::string end, Environment &env, bool throwup, F &&fx) {
+int begin_end_exec(std::string begin, std::string end, Environment &env, const fdmask &fds, bool throwup, F &&fx) {
 
 
 	bool echo = true;
@@ -610,8 +602,8 @@ int begin_end_exec(std::string begin, std::string end, Environment &env, bool th
 
 	try {
 		process p;
-		begin = expand_vars(begin, env);
-		end = expand_vars(end, env);
+		begin = expand_vars(begin, env, fds);
+		end = expand_vars(end, env, fds);
 
 		auto b = tokenize(begin, true);
 		auto e = tokenize(end, false);
@@ -638,12 +630,11 @@ int begin_end_exec(std::string begin, std::string end, Environment &env, bool th
 	}
 
 	return env.status(rv, throwup);
-
 }
 
 int begin_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-	return begin_end_exec(begin, end, env, throwup, [&](token_vector &b, process &p){
+	return begin_end_exec(begin, end, env, fds, throwup, [&](token_vector &b, process &p){
 
 		env.set("command", type == BEGIN ? "end" : ")");
 		if (b.size() != 1) {
@@ -663,53 +654,12 @@ int begin_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
 		return rv;
 	});
-
-#if 0
-
-	std::string b = expand_vars(begin, env);
-	std::string e = expand_vars(end, env);
-
-
-	env.set("command", type == BEGIN ? "end" : ")");
-
-	// echo!
-	env.echo("%s ... %s",
-		b.c_str(),
-		e.c_str()
-	);
-
-
-
-	// tokenize the begin and end commands.
-	// begin may not have extra arguments.  end may have redirection.
-
-	auto bt = tokenize(b, true);
-	if (bt.size() != 1) {
-		fprintf(stderr, "### Begin - Too many parameters were specified.\n");
-		fprintf(stderr, "Usage - Begin\n");
-		return env.status(-3);
-	}
-
-	fdmask newfds;
-	int status = check_ends(e, newfds);
-	newfds |= fds;
-	if (status) return env.status(status);
-
-	int rv;
-	env.indent_and([&]{
-		rv = vector_command::execute(env, newfds);		
-	});
-
-	env.echo("%s", type == BEGIN ? "end" : ")");
-
-	return env.status(rv);
-#endif
 }
 
 
 int loop_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-	return begin_end_exec(begin, end, env, throwup, [&](token_vector &b, process &p){
+	return begin_end_exec(begin, end, env, fds, throwup, [&](token_vector &b, process &p){
 
 		env.set("command", "end");
 		if (b.size() != 1) {
@@ -741,58 +691,11 @@ int loop_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
 		return rv;
 	});
-
-
-#if 0
-	std::string b = expand_vars(begin, env);
-	std::string e = expand_vars(end, env);
-
-
-	env.set("command", "end");
-
-	// echo!
-	env.echo("%s ... %s",
-		b.c_str(),
-		e.c_str()
-	);
-
-	// check for extra tokens...
-	auto bt = tokenize(b, true);
-	if (bt.size() != 1) {
-		fprintf(stderr, "### Loop - Too many parameters were specified.\n");
-		fprintf(stderr, "Usage - Loop\n");
-		return env.status(-3);
-	}
-
-	fdmask newfds;
-	int status = check_ends(e, newfds);
-	newfds |= fds;
-	if (status) return env.status(status);
-
-	int rv = 0;
-	for(;;) {
-
-		if (control_c) throw execution_of_input_terminated();
-
-		try {
-			env.loop_indent_and([&]{
-				rv = vector_command::execute(env, newfds);		
-			});
-		}
-		catch (break_command_t &ex) {
-			env.echo("end");
-			break;
-		}
-		catch (continue_command_t &ex) {}
-		env.echo("end");
-	}
-	return env.status(rv);
-#endif
 }
 
 int for_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
-	return begin_end_exec(begin, end, env, throwup, [&](token_vector &b, process &p){
+	return begin_end_exec(begin, end, env, fds, throwup, [&](token_vector &b, process &p){
 
 		env.set("command", "end");
 
@@ -826,56 +729,6 @@ int for_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 
 		return rv;
 	});
-
-#if 0
-	std::string b = expand_vars(begin, env);
-	std::string e = expand_vars(end, env);
-
-
-	env.set("command", "end");
-
-	// echo!
-	env.echo("%s ... %s",
-		b.c_str(),
-		e.c_str()
-	);
-
-	// check for extra tokens...
-	auto bt = tokenize(b, true);
-	if (bt.size() < 3 || strcasecmp(bt[2].string.c_str(), "in")) {
-		fprintf(stderr, "### For - Missing in keyword.\n");
-		fprintf(stderr, "Usage - For name in [word...]\n");
-		return env.status(-3);
-	}
-
-	fdmask newfds;
-	int status = check_ends(e, newfds);
-	newfds |= fds;
-	if (status) return env.status(status);
-
-	int rv = 0;
-	for (int i = 3; i < bt.size(); ++i ) {
-
-		if (control_c) throw execution_of_input_terminated();
-
-		env.set(bt[1].string, bt[i].string);
-
-		try {
-			env.loop_indent_and([&]{
-				rv = vector_command::execute(env, newfds);		
-			});
-		}
-		catch (break_command_t &ex) {
-			env.echo("end");
-			break;
-		}
-		catch (continue_command_t &ex) {}
-		env.echo("end");
-	}
-
-	return env.status(rv);
-
-#endif
 }
 
 
@@ -900,7 +753,7 @@ int if_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 		int tmp;
 		if (first) {
 			first = false;
-			tmp = begin_end_exec(c->clause, end, env, false, [&](token_vector &b, process &p){
+			tmp = begin_end_exec(c->clause, end, env, fds, false, [&](token_vector &b, process &p){
 
 				newfds = p.fds | fds;
 
@@ -922,7 +775,7 @@ int if_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 		}
 		else {
 		// second...
-			tmp = eval_exec(c->clause, env, false, [&](token_vector &b){
+			tmp = eval_exec(c->clause, env, fds, false, [&](token_vector &b){
 				if (skip || error) return 0;
 
 				int status = evaluate(c->type, std::move(b), env);
@@ -945,49 +798,5 @@ int if_command::execute(Environment &env, const fdmask &fds, bool throwup) {
 	env.echo("end");
 	if (error) return env.status(error, throwup);
 	return env.status(rv, throwup);
-
-#if 0
-
-
-
-
-	int rv = 0;
-	bool ok = false;
-
-	std::string e = expand_vars(end, env);
-
-	env.set("command", "end");
-
-	// parse end for indirection.
-	fdmask newfds;
-	int status = check_ends(e, newfds);
-	newfds |= fds;
-	if (status) {
-		rv = status;
-		ok = true;
-	}
-
-	for (auto &c : clauses) {
-		std::string s = expand_vars(c->clause, env);
-
-		if (c->type == IF)
-			env.echo("%s ... %s", s.c_str(), e.c_str());
-		else
-			env.echo("%s", s.c_str());
-
-		if (ok) continue;
-
-		int tmp = evaluate(c->type, s, env);
-		if (tmp < 0) { ok = true; rv = tmp; continue; }
-		if (tmp == 0) continue;
-
-		env.indent_and([&](){
-			rv = c->execute(env, newfds);
-		});
-	}
-
-	env.echo("end");
-	return env.status(rv);
-#endif
 }
 

command.h

@@ -6,7 +6,7 @@
 #include <vector>
 #include <array>
 #include <string>
-#include "phase2-parser.h"
+#include "phase3.h"
 
 typedef std::unique_ptr<struct command> command_ptr;
 typedef std::vector<command_ptr> command_ptr_vector;
@@ -22,7 +22,7 @@ struct command {
 	{}
 
 	virtual bool terminal() const noexcept {
-		return type == EVALUATE || type == COMMAND || type == BREAK || type == CONTINUE || type == ERROR;
+		return type == EVALUATE || type == COMMAND || type == BREAK || type == CONTINUE || type == ERROR || type == EXIT;
 	}
 
 	int type = 0;
@@ -81,6 +81,15 @@ struct continue_command : public command {
 	virtual int execute(Environment &e, const fdmask &fds, bool throwup) final override;
 };
 
+struct exit_command : public command {
+
+	template<class S>
+	exit_command(S &&s) : command(EXIT), text(std::forward<S>(s))
+	{}
+
+	std::string text;
+	virtual int execute(Environment &e, const fdmask &fds, bool throwup) final override;
+};
 
 
 struct binary_command : public command {

config.h.in

@@ -0,0 +1,7 @@
+#ifndef __mpw_shell_config_h__
+#define __mpw_shell_config_h__
+
+#cmakedefine HAVE_DPRINTF
+
+#endif
+

cxx/filesystem.cpp

@@ -269,10 +269,10 @@ namespace filesystem {
 	path current_path(error_code& ec) {
 
 		char *cp;
-		char buffer[PATH_MAX];
+		char buffer[PATH_MAX+1];
 
 		ec.clear();
-		cp = ::getcwd(buffer, sizeof(buffer));
+		cp = ::getcwd(buffer, PATH_MAX);
 		if (cp) return path(cp);
 
 		ec = error_code(errno, std::system_category());
@@ -304,7 +304,7 @@ namespace filesystem {
 
 	path canonical(const path& p, error_code& ec) {
 		char *cp;
-		char buffer[PATH_MAX];
+		char buffer[PATH_MAX+1];
 
 		ec.clear();
 		cp = realpath(p.c_str(), buffer);
@@ -316,7 +316,7 @@ namespace filesystem {
 	path canonical(const path& p, const path& base, error_code& ec) {
 
 		char *cp;
-		char buffer[PATH_MAX];
+		char buffer[PATH_MAX+1];
 		
 		ec.clear();
 

cxx/mapped_file.cpp

@@ -23,17 +23,12 @@ namespace {
 		FX _fx;
 	};
 
-	void throw_error(int error) {
-		throw std::system_error(error, std::system_category());
+
+	void set_or_throw_error(std::error_code *ec, int error, const std::string &what) {
+		if (ec) *ec = std::error_code(error, std::system_category());
+		else throw std::system_error(error, std::system_category(), what);
 	}
 
-
-	void throw_error(int error, const std::string &what) {
-		throw std::system_error(error, std::system_category(), what);
-	}
-
-
-
 }
 
 #ifdef _WIN32
@@ -41,12 +36,8 @@ namespace {
 
 namespace {
 
-	void throw_error() {
-		throw_error(GetLastError());
-	}
-
-	void throw_error(const std::string &what) {
-		throw_error(GetLastError(), what);
+	void set_or_throw_error(std::error_code *ec, const std::string &what) {
+		set_or_throw_error(ec, GetLastError(), what);
 	}
 
 }
@@ -61,7 +52,7 @@ void mapped_file_base::close() {
 	}
 }
 
-void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, size_t offset) {
+void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, size_t offset, std::error_code *ec) {
 
 
 	HANDLE fh;
@@ -70,9 +61,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 	// length of 0 in CreateFileMapping / MapViewOfFile
 	// means map the entire file.
 
-	if (is_open()) {
-		throw std::runtime_error("mapped_file_base::open - file already open");
-	}
+	if (is_open()) close();
 
 	fh = CreateFile(p.c_str(), 
 		flags == readonly ? GENERIC_READ : GENERIC_READ | GENERIC_WRITE,
@@ -83,7 +72,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 		nullptr
 	);
 	if (fh == INVALID_HANDLE_VALUE) {
-		throw_error();
+		return set_or_throw_error(ec, "CreateFile");
 	}
 
 	auto fh_close = make_unique_resource(fh, CloseHandle);
@@ -116,7 +105,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 
 	mh = CreateFileMapping(fh, nullptr, protect, 0, 0, 0);
 	if (mh == INVALID_HANDLE_VALUE) {
-		throw_error();
+		return set_or_throw_error(ec, "CreateFileMapping");
 	}
 
 	auto mh_close = make_unique_resource(mh, CloseHandle);
@@ -129,7 +118,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 		length, 
 		nullptr);
 	if (!_data) {
-		throw_error();
+		return set_or_throw_error(ec, "MapViewOfFileEx");
 	}
 
 
@@ -152,10 +141,7 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 	const DWORD access = FILE_MAP_WRITE;
 
 
-	if (is_open()) {
-		throw std::runtime_error("mapped_file_base::create - file already open");
-	}
-
+	if (is_open()) close();
 
 	fh = CreateFile(p.c_str(), 
 		GENERIC_READ | GENERIC_WRITE,
@@ -166,7 +152,7 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 		nullptr
 	);
 	if (fh == INVALID_HANDLE_VALUE) {
-		throw_error();
+		return set_or_throw_error(nullptr, "CreateFile");
 	}
 
 	auto fh_close = make_unique_resource(fh, CloseHandle);
@@ -174,11 +160,11 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 
 	file_size.QuadPart = length;
 	if (!SetFilePointerEx(fh, file_size, nullptr, FILE_BEGIN));
-	if (!SetEndOfFile(fh)) throw_error();
+	if (!SetEndOfFile(fh)) return set_or_throw_error(nullptr, "SetEndOfFile");
 
 	mh = CreateFileMapping(fh, nullptr, protect, 0, 0, 0);
 	if (mh == INVALID_HANDLE_VALUE) {
-		throw_error();
+		return set_or_throw_error(nullptr, "CreateFileMapping");
 	}
 
 	auto mh_close = make_unique_resource(mh, CloseHandle);
@@ -191,7 +177,7 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 		nullptr);
 
 	if (!_data) {
-		throw_error();
+		return set_or_throw_error(nullptr, "MapViewOfFileEx");
 	}
 
 	_file_handle = fh_close.release();
@@ -213,13 +199,10 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 
 namespace {
 
-	void throw_error() {
-		throw_error(errno);
+	void set_or_throw_error(std::error_code *ec, const std::string &what) {
+		set_or_throw_error(ec, errno, what);
 	}
 
-	void throw_error(const std::string &what) {
-		throw_error(errno, what);
-	}
 
 }
 
@@ -232,15 +215,15 @@ void mapped_file_base::close() {
 }
 
 
-void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, size_t offset) {
+void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, size_t offset, std::error_code *ec) {
+
+	if (ec) ec->clear();
 
 	int fd;
 
 	int oflags = 0;
 
-	if (is_open()) {
-		throw std::runtime_error("mapped_file_base::open - file already open");
-	}
+	if (is_open()) close();
 
 	switch (flags) {
 	case readonly:
@@ -253,7 +236,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 
 	fd = ::open(p.c_str(), oflags);
 	if (fd < 0) {
-		throw_error(errno);
+		return set_or_throw_error(ec, "open");
 	}
 
 	//defer([fd](){::close(fd); });
@@ -265,7 +248,8 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 		struct stat st;
 
 		if (::fstat(fd, &st) < 0) {
-			throw_error(errno);
+			set_or_throw_error(ec, "stat");
+			return;
 		}
 		length = st.st_size;
 	}
@@ -279,7 +263,7 @@ void mapped_file_base::open(const path_type& p, mapmode flags, size_t length, si
 
 	if (_data == MAP_FAILED) {
 		_data = nullptr;
-		throw_error(errno);
+		return set_or_throw_error(ec, "mmap");
 	}
 
 	_fd = close_fd.release();
@@ -292,15 +276,11 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 	int fd;
 	const size_t offset = 0;
 
-	if (is_open()) {
-		throw std::runtime_error("mapped_file_base::create - file already open");
-	}
-
-
+	if (is_open()) close();
 
 	fd = ::open(p.c_str(), O_RDWR | O_CREAT | O_TRUNC);
 	if (fd < 0) {
-		throw_error(errno);
+		return set_or_throw_error(nullptr, "open");
 	}
 
 	//defer([fd](){::close(fd); });
@@ -309,7 +289,7 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 
 
 	if (::ftruncate(fd, length) < 0) {
-		throw_error(errno);
+		return set_or_throw_error(nullptr, "ftruncate");
 	}
 
 
@@ -320,7 +300,7 @@ void mapped_file_base::create(const path_type& p, size_t length) {
 
 	if (_data == MAP_FAILED) {
 		_data = nullptr;
-		throw_error(errno);
+		return set_or_throw_error(nullptr, "mmap");
 	}
 
 	_fd = close_fd.release();

cxx/mapped_file.h

@@ -8,7 +8,7 @@
 #endif
 
 #include <cstddef>
-
+#include <system_error>
 
 class mapped_file_base {
 public:
@@ -40,7 +40,7 @@ protected:
 
 	void swap(mapped_file_base &rhs);
 
-	void open(const path_type& p, mapmode flags, size_t length, size_t offset);
+	void open(const path_type& p, mapmode flags, size_t length, size_t offset, std::error_code *ec);
 	void create(const path_type &p, size_t new_size); // always creates readwrite.
 	void reset();
 
@@ -79,6 +79,22 @@ public:
 		open(p, flags, length, offset);
 	}
 
+	mapped_file(const path_type &p, std::error_code &ec) noexcept {
+		open(p, readonly, -1, 0, ec);
+	}
+	mapped_file(const path_type &p, mapmode flags, std::error_code &ec) noexcept {
+		open(p, flags, -1, 0, ec);
+	}
+
+	mapped_file(const path_type &p, mapmode flags, size_t length, std::error_code &ec) noexcept {
+		open(p, flags, length, 0, ec);
+	}
+
+	mapped_file(const path_type &p, mapmode flags, size_t length, size_t offset, std::error_code &ec) noexcept {
+		open(p, flags, length, offset, ec);
+	}
+
+
 	mapped_file(mapped_file &&);
 	mapped_file(const mapped_file &) = delete;
 
@@ -87,7 +103,20 @@ public:
 
 
 	void open(const path_type& p, mapmode flags, size_t length = -1, size_t offset = 0) {
-		base::open(p, flags, length, offset);
+		base::open(p, flags, length, offset, nullptr);
+	}
+
+	void open(const path_type &p, std::error_code &ec) noexcept {
+		base::open(p, readonly, -1, 0, &ec);
+	}
+	void open(const path_type &p, mapmode flags, std::error_code &ec) noexcept {
+		base::open(p, flags, -1, 0, &ec);
+	}
+	void open(const path_type &p, mapmode flags, size_t length, std::error_code &ec) noexcept {
+		base::open(p, flags, length, 0, &ec);
+	}
+	void open(const path_type &p, mapmode flags, size_t length, size_t offset, std::error_code &ec) noexcept {
+		base::open(p, flags, length, offset, &ec);
 	}
 
 

error.h

@@ -67,4 +67,15 @@ public:
 	{}
 };
 
+/*
+  these are used for flow-control.
+  they do not inherit from std::exception to prevent being caught
+  by normal handlers.
+*/
+
+struct break_command_t {};
+struct continue_command_t {};
+struct exit_command_t { int value = 0; };
+struct quit_command_t {};
+
 #endif

etc/Startup

@@ -49,3 +49,9 @@ set -e MWCIncludes "{CIncludes}"
 set -e ARMCIncludes "{MPW}Interfaces:ARMCIncludes:"
 
 set -e AsmMatOpts "-t 4"
+
+# customizations can go in the UserStartup file.
+if `exists {MPW}UserStartup` != ""
+	execute {MPW}UserStartup
+end
+

macroman.cpp

@@ -81,7 +81,7 @@ std::string utf8_to_macroman(const std::string &s) {
 	rv.reserve(s.size());
 
 	unsigned cs = 0;
-	uint16_t tmp;
+	uint16_t tmp = 0;
 
 	for (unsigned char c : s) {
 		switch(cs) {

mpw-shell-expand.rl

@@ -4,6 +4,8 @@
 #include <string>
 #include <unordered_map>
 #include <stdexcept>
+#include <system_error>
+#include <algorithm>
 
 #include <stdio.h>
 
@@ -46,12 +48,25 @@
 	action epush { /* epush */ ev.push_back(fc); }
 	action efinish1 {
 		/* efinish1 */
+
+		/*
 		throw std::runtime_error("MPW Shell - `...` not yet supported.");
+		*/
+
+		std::string s = subshell(ev, env, fds);
+		scratch.append(s);
+
 		fgoto *xcs;
 	}
 	action efinish2 {
 		/* efinish2 */
-		throw std::runtime_error("MPW Shell - `...` not yet supported.");
+
+		std::string s = subshell(ev, env, fds);
+		for (auto c : s) {
+			if (c == '\'' || c == '"' ) scratch.push_back(escape);
+			scratch.push_back(c);
+		}
+
 		fgoto *xcs;
 	}
 
@@ -110,9 +125,48 @@
 
 namespace {
 	%% write data;
+
+
+std::string subshell(const std::string &s, Environment &env, const fdmask &fds) {
+	
+
+	char temp[32] = "/tmp/mpw-shell-XXXXXXXX";
+
+	int fd = mkstemp(temp);
+	unlink(temp);
+
+	fdset new_fds;
+	new_fds.set(1, fd);
+
+	int rv = 0;
+	env.indent_and([&](){
+
+		rv = read_string(env, s, new_fds | fds);
+
+	});
+
+	std::string tmp;
+	lseek(fd, 0, SEEK_SET);
+	for(;;) {
+		uint8_t buffer[1024];
+		ssize_t len = read(fd, buffer, sizeof(buffer));
+		if (len == 0) break;
+		if (len < 0) {
+			if (errno == EINTR) continue;
+			throw std::system_error(errno, std::system_category(), "read");
+		}
+		tmp.append(buffer, buffer + len);
+	}
+	std::transform(tmp.begin(), tmp.end(), tmp.begin(), [](uint8_t x){
+		if (x == '\r' || x == '\n') x = ' ';
+		return x;
+	});
+	return tmp;
 }
 
-std::string expand_vars(const std::string &s, const Environment &env) {
+}
+
+std::string expand_vars(const std::string &s, Environment &env, const fdmask &fds) {
 	if (s.find_first_of("{`", 0, 2) == s.npos) return s;
 
 	int cs;

mpw-shell-token.rl

@@ -106,7 +106,7 @@
 
 
 			'-'  when eval
-				 %push_token => { tokens.emplace_back("+", '-'); };
+				 %push_token => { tokens.emplace_back("-", '-'); };
 
 			'!'  when eval
 				 %push_token => { tokens.emplace_back("!", '!'); };

mpw-shell.cpp

@@ -2,6 +2,8 @@
 #include <vector>
 #include <string>
 #include <unordered_map>
+#include <atomic>
+#include <algorithm>
 
 #include <unistd.h>
 #include <fcntl.h>
@@ -10,16 +12,15 @@
 #include <cerrno>
 #include <signal.h>
 #include <sys/wait.h>
+#include <getopt.h>
 
 #include "mpw-shell.h"
+#include "mpw_parser.h"
+
 #include "fdset.h"
 
 #include "macroman.h"
 
-#include "phase1.h"
-#include "phase2.h"
-#include "command.h"
-
 #include "cxx/mapped_file.h"
 #include "cxx/filesystem.h"
 #include "cxx/string_splitter.h"
@@ -33,7 +34,6 @@
 #include <pwd.h>
 #include <sysexits.h>
 #include <paths.h>
-#include <atomic>
 
 #include "version.h"
 
@@ -80,42 +80,73 @@ void init(Environment &env) {
 }
 
 
-int read_file(phase1 &p, const std::string &file) {
-	const mapped_file mf(file, mapped_file::readonly);
 
-	p.process(mf.begin(), mf.end(), false);
-	p.finish();
-	return 0;
+int read_file(Environment &e, const std::string &file, const fdmask &fds) {
+	std::error_code ec;
+	const mapped_file mf(file, mapped_file::readonly, ec);
+	if (ec) {
+		fprintf(stderr, "# Error reading %s: %s\n", file.c_str(), ec.message().c_str());
+		return e.status(-1, false);
 	}
 
-int read_fd(phase1 &p, int fd) {
+
+	mpw_parser p(e, fds);
+	e.status(0, false);
+
+	try {
+		p.parse(mf.begin(), mf.end());
+		p.finish();
+	} catch(const execution_of_input_terminated &ex) {
+		return ex.status();
+	}
+	return e.status();
+}
+
+
+int read_string(Environment &e, const std::string &s, const fdmask &fds) {
+	mpw_parser p(e, fds);
+	e.status(0, false);
+	try {
+		p.parse(s);
+		p.finish();
+	} catch(const execution_of_input_terminated &ex) {
+		return ex.status();
+	}
+	return e.status();
+
+}
+
+
+int read_fd(Environment &e, int fd, const fdmask &fds) {
 
 	unsigned char buffer[2048];
 	ssize_t size;
 
+	mpw_parser p(e, fds);
+	e.status(0, false);
+
+	try {
 		for (;;) {
 			size = read(fd, buffer, sizeof(buffer));
 			if (size < 0) {
 				if (errno == EINTR) continue;
-			perror("read: ");
-			return -1;
-		}
-		try {
-			if (size == 0) p.finish();
-			else p.process(buffer, buffer + size);
-		} catch(std::exception &ex) {
-			fprintf(stderr, "### %s\n", ex.what());
-			p.reset();
+				perror("read");
+				e.status(-1, false);
 			}
 			if (size == 0) break;
+			p.parse(buffer, buffer + size);
 		}
-
-	return 0;
+		p.finish();
+	} catch(const execution_of_input_terminated &ex) {
+		return ex.status();
+	}
+	return e.status();
 }
 
 void launch_mpw(const Environment &env, const std::vector<std::string> &argv, const fdmask &fds);
+fs::path which(const Environment &env, const std::string &name);
 
-int read_make(phase1 &p1, phase2 &p2, Environment &env, const std::vector<std::string> &argv) {
+int read_make(Environment &env, const std::vector<std::string> &argv) {
 
 	int out[2];
 	int ok;
@@ -147,10 +178,9 @@ int read_make(phase1 &p1, phase2 &p2, Environment &env, const std::vector<std::s
 	}
 
 	close(out[1]);
-	int rv = read_fd(p1, out[0]);
+	int rv = read_fd(env, out[0]);
 	close(out[0]);
-	p1.finish();
-	p2.finish();
+
 
 	// check for make errors.
 	for(;;) {
@@ -176,7 +206,7 @@ int read_make(phase1 &p1, phase2 &p2, Environment &env, const std::vector<std::s
 		exit(EX_OSERR);
 	}
 
-	return env.status();
+	return rv;
 }
 
 std::atomic<int> control_c{0};
@@ -190,7 +220,7 @@ void control_c_handler(int signal, siginfo_t *sinfo, void *context) {
 }
 
 
-int interactive(Environment &env, phase1 &p1, phase2& p2) {
+int interactive(Environment &env) {
 
 	std::string history_file = root();
 	history_file += ".history";
@@ -207,18 +237,18 @@ int interactive(Environment &env, phase1 &p1, phase2& p2) {
 
 	sigaction(SIGINT, &act, &old_act);
 
+	mpw_parser p(env, true);
 
 
 	for(;;) {
 		const char *prompt = "# ";
-		if (p1.continuation() || p2.continuation()) prompt = "> ";
+		if (p.continuation()) prompt = "> ";
 		char *cp = readline(prompt);
 		if (!cp) {
 			if (control_c) {
 				control_c = 0;
 				fprintf(stdout, "\n");
-				p1.abort();
-				p2.abort();
+				p.abort();
 				env.status(-9, false);
 				continue;
 			}
@@ -240,29 +270,17 @@ int interactive(Environment &env, phase1 &p1, phase2& p2) {
 			s = utf8_to_macroman(s);
 
 		s.push_back('\n');
-		try {
-			p1.process(s);
 
-		} catch(std::exception &ex) {
-			fprintf(stderr, "### %s\n", ex.what());
-			p1.reset();
-		}
+		p.parse(s);
 
 	}
-
-	try {
-		p1.finish();
-	} catch(std::exception &ex) {
-		fprintf(stderr, "### %s\n", ex.what());
-		p1.reset();
-	}
+	p.finish();
 
 	sigaction(SIGINT, &old_act, nullptr);
 
 	write_history(history_file.c_str());
 	fprintf(stdout, "\n");
 
-
 	return 0;
 }
 
@@ -294,6 +312,10 @@ void define(Environment &env, const std::string &s) {
 
 }
 
+/*
+ *
+ * todo:  prevent -r and -s (don't generate shell code)
+ */
 void make_help(void) {
 
 	#undef _
@@ -329,59 +351,92 @@ int make(int argc, char **argv) {
 
 	std::vector<std::string> args;
 	args.reserve(argc+1);
-	bool __ = false;
+	int c;
+	bool passthrough = false;
 
-	args.emplace_back("make");
-
-	for (auto iter = argv; *iter; ++iter) {
-		std::string tmp(*iter);
-
-		if (!__) {
-			if (tmp == "--")
-				{ __ = true; continue; }
-
-			if (tmp == "--help")
-				{ make_help(); exit(0); }
-
-			if (tmp == "--test" || tmp == "--dry-run") 
-				{ e.set("test", "1"); continue; }
-		}
-		args.emplace_back(std::move(tmp));
-
-	}
-
-	phase1 p1;
-	phase2 p2;
-
-	p1 >>= [&p2](std::string &&s) {
-		if (s.empty()) p2.finish();
-		else p2(std::move(s));
+	static struct option longopts[] = {
+		{ "help",    no_argument, nullptr, 'h' },
+		{ "verbose", no_argument, nullptr, 'v' },
+		{ "test",    no_argument, nullptr, 1 },
+		{ "dry-run", no_argument, nullptr, 2 },
+		{ nullptr, 0, nullptr, 0},
 	};
 
-	p2 >>= [&e](command_ptr_vector &&v) {
+	args.push_back(""); // place-holder.
 
-		for (auto iter = v.begin(); iter != v.end(); ++iter) {
-			auto &ptr = *iter;
-			fdmask fds;
-			try {
-				ptr->execute(e, fds);
-			} catch (execution_of_input_terminated &ex) {
-				control_c = 0;
-				fprintf(stderr, "### %s\n", ex.what());
-				if (e.exit()) 
-					exit(ex.status());
-				e.status(ex.status(), false);
+	while ((c = getopt_long(argc, argv, "d:ef:i:prstuvwy", longopts, nullptr)) != -1) {
+		std::string flag = "-"; flag.push_back(c);
+		switch(c) {
+			default:
+				make_help();
+				return EX_USAGE;
+
+			case 'h':
+				make_help();
+				return 0;
+
+			case 1:
+				e.set("test", 1);
+				break;
+
+			case 2:
+				passthrough = true;
+				break;
+
+			case 'd':
+			case 'f':
+			case 'i':
+				args.push_back(std::move(flag));
+				args.push_back(optarg);
+				break;
+
+			case 'e':
+			case 'p':
+			case 't':
+			case 'u':
+			case 'v':
+			case 'w':
+			case 'y':
+				args.push_back(std::move(flag));
+				break;
+
+			case 'r':
+			case 's':
+				args.push_back(std::move(flag));
+				passthrough = true;
+				break;
 		}
+
+
 	}
-	};
+
+	argc -= optind;
+	argv += optind;
+	std::transform(argv, argv+argc, std::back_inserter(args), [](const char *cp){
+		return std::string(cp);
+	});
+
 
 
 	e.startup(true);
-	read_file(p1, root() / "Startup");
+	read_file(e, root() / "Startup");
 	e.startup(false);
 
+	auto path = which(e, "Make");
+	if (path.empty()) {
+		fputs("### MPW Shell - Command \"Make\" was not found.\n", stderr);
+		return -1;
+	}
+	e.set("command", path);
+	args[0] = path;
 
-	return read_make(p1, p2, e, args);
+	if (passthrough) {
+
+		launch_mpw(e, args, fdmask());
+		exit(EX_OSERR);
+	}
+
+	return read_make(e, args);
 
 }
 
@@ -458,8 +513,11 @@ int main(int argc, char **argv) {
 	mpw_path();
 
 	fs::path self = fs::path(argv[0]).filename();
-	if (self == "mpw-make") return make(argc - 1, argv + 1);
-	if (self == "mpw-shell" && argc > 1 && !strcmp(argv[1],"make")) return make(argc - 2, argv + 2);
+	if (self == "mpw-make") return make(argc, argv);
+	if (self == "mpw-shell" && argc > 1 && !strcmp(argv[1],"make")) {
+		argv[1] = (char *)"mpw-make";
+		return make(argc - 1, argv + 1);
+	}
 	
 	Environment e;
 	init(e);
@@ -499,59 +557,38 @@ int main(int argc, char **argv) {
 
 
 
-
-
-	phase1 p1;
-	phase2 p2;
-
-	p1 >>= [&p2](std::string &&s) {
-		if (s.empty()) p2.finish();
-		else p2(std::move(s));
-	};
-
-	p2 >>= [&e](command_ptr_vector &&v) {
-
-		for (auto iter = v.begin(); iter != v.end(); ++iter) {
-			auto &ptr = *iter;
-			fdmask fds;
-			try {
-				ptr->execute(e, fds);
-			} catch (execution_of_input_terminated &ex) {
-				control_c = 0;
-				if (!(ptr->terminal() && ++iter == v.end())) {
-					fprintf(stderr, "### %s\n", ex.what());
-				}
-				e.status(ex.status(), false);
-				return;
-			}
-		}
-	};
-
 	if (!cflag) fprintf(stdout, "MPW Shell " VERSION "\n");
 	if (!fflag) {
 		fs::path startup = root() / "Startup";
 		e.startup(true);
+		mpw_parser p(e);
+
 		try {
-			read_file(p1, startup);
+			read_file(e, startup);
 		} catch (const std::system_error &ex) {
 			fprintf(stderr, "### %s: %s\n", startup.c_str(), ex.what());
+		} catch (const quit_command_t &) {
 		}
+
 		e.startup(false);
 	}
 
+	try {
+
+		int rv = 0;
 		if (cflag) {
-		std::string s(cflag);
-		s.push_back('\n');
-		p1.process(s, true);
-		p2.finish();
-		exit(e.status());
+			rv = read_string(e, cflag);
+			exit(rv);
 		}
 
 		if (isatty(STDIN_FILENO))
-		interactive(e, p1, p2);
+			rv = interactive(e);
 		else 
-		read_fd(p1, STDIN_FILENO);
-	p2.finish();
+			rv = read_fd(e, STDIN_FILENO);
 
-	exit(e.status());
+		exit(rv);
+	}
+	catch (const quit_command_t &) {
+		exit(0);
+	}
 }

mpw-shell.h

@@ -8,6 +8,7 @@
 #include <cstdint>
 
 #include "environment.h"
+#include "fdset.h"
 
 const unsigned char escape = 0xb6;
 
@@ -49,7 +50,7 @@ public:
 
 
 std::vector<token> tokenize(std::string &s, bool eval = false);
-std::string expand_vars(const std::string &s, const class Environment &);
+std::string expand_vars(const std::string &s, class Environment &, const fdmask &fds = fdmask());
 
 //std::string quote(std::string &&s);
 std::string quote(const std::string &s);
@@ -67,4 +68,9 @@ int32_t evaluate_expression(const std::string &name, std::vector<token> &&tokens
 
 
 
+int read_file(Environment &e, const std::string &file, const fdmask &fds = fdmask());
+int read_string(Environment &e, const std::string &s, const fdmask &fds = fdmask());
+int read_fd(Environment &e, int fd, const fdmask &fds = fdmask());
+
+
 #endif

mpw_parser.cpp

@@ -0,0 +1,106 @@
+#include <algorithm>
+
+#include "mpw_parser.h"
+#include "phase3_parser.h"
+
+#include "command.h"
+#include "error.h"
+
+mpw_parser::mpw_parser(Environment &e, fdmask fds, bool interactive) : _env(e), _fds(fds), _interactive(interactive)
+{
+
+	_p3 = phase3::make();
+	_p2.set_next([this](int type, std::string &&s){
+		_p3->parse(type, std::move(s));
+	});
+
+	_p1.set_next([this](std::string &&s){
+		_p2.parse(std::move(s));
+	});
+}
+
+
+mpw_parser::~mpw_parser() {
+
+}
+
+
+bool mpw_parser::continuation() const {
+	if (_p1.continuation()) return true;
+	if (_p2.continuation()) return true;
+	if (_p3->continuation()) return true;
+	return false;
+}
+
+void mpw_parser::finish() {
+	_p1.finish();
+	_p2.finish();
+	_p3->parse(0, "");
+
+	// and now execute the commands...
+	execute();
+}
+
+
+void mpw_parser::reset() {
+	_p1.reset();
+	_p2.reset();
+	_p3->reset();
+	_abort = false;
+}
+
+void mpw_parser::abort() {
+	_p1.abort();
+	_p2.abort();
+	//_p3->abort();
+	_p3->reset();
+	_abort = true;
+}
+
+
+void mpw_parser::parse(const void *begin, const void *end) {
+	if (_abort) return;
+	_p1.parse((const unsigned char *)begin, (const unsigned char *)end);
+
+	// and execute...
+	execute();
+}
+
+
+void mpw_parser::execute() {
+	if (_abort) {
+		_p3->command_queue.clear();
+		return;
+	}
+
+	auto commands = std::move(_p3->command_queue);
+	_p3->command_queue.clear();
+
+
+	std::reverse(commands.begin(), commands.end());
+
+	command_ptr cmd;
+
+
+	try {
+		while (!commands.empty()) {
+			cmd = std::move(commands.back());
+			commands.pop_back();
+			cmd->execute(_env, _fds);
+		}
+
+	} catch (execution_of_input_terminated &ex) {
+
+		_env.status(ex.status(), false);
+
+		if (_interactive) {
+			if (!cmd->terminal() || !commands.empty()) {
+				if (ex.status()) fprintf(stderr, "### %s\n", ex.what());
+			}
+			return;
+		}
+		_abort = true;
+		throw;
+	}
+
+}

mpw_parser.h

@@ -0,0 +1,59 @@
+#ifndef __mpw_parser__
+#define __mpw_parser__
+
+#include <string>
+#include <memory>
+
+#include "environment.h"
+#include "fdset.h"
+
+#include "phase1.h"
+#include "phase2.h"
+
+class mpw_parser {
+
+public:
+
+	mpw_parser(Environment &e, fdmask fds = fdmask(), bool interactive = false);
+	mpw_parser(Environment &e, bool interactive) : mpw_parser(e, fdmask(), interactive)
+	{}
+
+	~mpw_parser();
+
+	void parse(const void *begin, const void *end);
+	void parse(const std::string &s) {
+		parse(s.data(), s.data() + s.size());
+	}
+	void parse(const void *begin, size_t length) {
+		parse(begin, (const char *)begin + length);
+	}
+
+	void reset();
+	void abort();
+	void finish();
+
+	bool continuation() const;
+
+private:
+
+	mpw_parser& operator=(const mpw_parser &) = delete;
+	mpw_parser& operator=(mpw_parser &&) = delete;
+
+	mpw_parser(const mpw_parser &) = delete;
+	mpw_parser(mpw_parser &&) = delete;
+
+	void execute();
+
+	Environment &_env;
+	fdmask _fds;
+	bool _interactive = false;
+	bool _abort = false;
+
+	phase1 _p1;
+	phase2 _p2;
+	std::unique_ptr<class phase3> _p3;
+
+};
+
+
+#endif

phase1.cpp

@@ -150,19 +150,10 @@ text:
 }
 
 
-void phase1::process(const std::string &s, bool final) {
-	
-	for (auto c : s) {
-		cs = process(c, cs);
-	}
-	if (final) finish();
-}
-
-void phase1::process(const unsigned char *begin, const unsigned char *end, bool final) {
+void phase1::parse(const unsigned char *begin, const unsigned char *end) {
 	while (begin != end) {
 		cs = process(*begin++, cs);
 	}
-	if (final) finish();
 }
 
 void phase1::finish() {
@@ -181,7 +172,6 @@ void phase1::reset() {
 void phase1::flush() {
 	multiline = false;
 	if (scratch.empty()) return;
-	// strip trailing whitespace?
-	if (pipe_to) pipe_to(std::move(scratch));
+	if (_then) _then(std::move(scratch));
 	scratch.clear();
 }

phase1.h

@@ -8,47 +8,33 @@
 class phase1 {
 	
 public:
-	typedef std::function<void(std::string &&)> pipe_function;
+
+	typedef std::function<void(std::string &&)> next_function_type;
 
 	phase1() = default;
 
-	void process(const unsigned char *begin, const unsigned char *end, bool final = false);
-
-	void process(const char *begin, const char *end, bool final = false) {
-		process((const unsigned char *)begin, (const unsigned char *)end, final);
-	}
-
-	void process(const std::string &s, bool final = false);// { process(s.data(), s.data() + s.size(), final); }
-
-	void finish();// { const char *tmp = "\n"; process(tmp, tmp+1, true); }
+	void parse(const unsigned char *begin, const unsigned char *end);
+	void parse(const std::string &s) { parse((const unsigned char *)s.data(), (const unsigned char *)s.data() + s.size()); }
+	void finish();
 
 	void reset();
 	void abort() { reset(); }
 
-
-	phase1 &operator >>= (pipe_function f) { pipe_to = f; return *this; }
-
-
-	template<class F>
-	phase1 &operator >>= (F &f) { 
-		using std::placeholders::_1;
-		pipe_to = std::bind(&F::operator(), &f, _1);
-		return *this;
-	}
-
-
 	bool continuation() const { return multiline; }
 
+	void set_next(next_function_type &&fx) { _then = std::move(fx); }
+
 private:
 
 	int process(unsigned char, int);
 	void flush();
 
 	std::string scratch;
-	pipe_function pipe_to;
 	int line = 1;
 	int cs = 0;
 	bool multiline = false;
+
+	next_function_type _then;
 };
 
 #endif

phase2.h

@@ -3,95 +3,41 @@
 #define __phase2_h__
 
 #include <string>
-#include <vector>
 #include <functional>
-#include <memory>
-
-#include "command.h"
-#include <lemon_base.h>
-
-//typedef std::unique_ptr<struct command> command_ptr;
-//typedef std::vector<command_ptr> command_ptr_vector;
-
-class phase2_parser : public lemon_base<std::string> {
-
-public:
-	static std::unique_ptr<phase2_parser> make();
-
-	virtual void syntax_error(int yymajor, std::string &yyminor) override final;
-	virtual void parse_accept() override final;
-	virtual void parse_failure() override final;
-
-	bool continuation() const;
-
-private:
-	friend class phase2;
-
-	phase2_parser(const phase2_parser &) = delete;
-	phase2_parser(phase2_parser &&) = delete;
-
-	phase2_parser& operator=(const phase2_parser &) = delete;
-	phase2_parser& operator=(phase2_parser &&) = delete;
-
-protected:
-	// these need to be accessible to the lemon-generated parser.
-	phase2_parser() = default;
-
-	command_ptr_vector command_queue;
-	bool error = false;
-};
-
 
 class phase2  {
 	
 public:
-	typedef std::function<void(command_ptr_vector &&)> pipe_function;
 
-	phase2();
-	phase2(const phase2 &) = delete;
-	phase2(phase2 &&) = default;
+	typedef std::function<void(int, std::string &&)> next_function_type;
 
-	phase2 & operator=(const phase2 &) = delete;
-	phase2 & operator=(phase2 &&) = default;
+	phase2() = default;
 
-	void operator()(const std::string &line) { process(line); }
-	void process(const std::string &line);
+	void parse(std::string &&);
 	void finish();
 
-	phase2 &operator >>=(pipe_function f) { pipe_to = f; return *this; }
+	void reset();
+	void abort() { reset(); }
 
-	template<class F>
-	phase2 &operator >>= (F &f) { 
-		using std::placeholders::_1;
-		pipe_to = std::bind(&F::operator(), &f, _1);
-		return *this;
-	}
+	bool continuation() const { return false; }
 
-	bool continuation() const {
-		return parser ? parser->continuation() : false;
-	}
-
-	void abort();
+	void set_next(next_function_type &&fx) { _then = std::move(fx); }
 
 private:
 
-	void parse(int, std::string &&);
-
-
-	std::unique_ptr<phase2_parser> parser;
+	void parse(int type, std::string &&s);
 
 	std::string scratch;
 	int type = 0;
 	int pcount = 0;
 
-	pipe_function pipe_to;
 
 	void flush();
 	bool special();
 	int classify();
 	void exec();
 
-
+	next_function_type _then;
 };
 
 

phase2.rl

@@ -4,9 +4,8 @@
  *
  */
 
-#include "phase2-parser.h"
 #include "phase2.h"
-#include "command.h"
+#include "phase3.h"
 
 %%{
 	machine main;
@@ -194,6 +193,7 @@ int phase2::classify() {
 	_("else", ELSE)
 	_("end", END)
 	_("evaluate", EVALUATE)
+	_("exit", EXIT)
 	_("for", FOR)
 	_("if", IF)
 	_("loop", LOOP)
@@ -217,9 +217,7 @@ void phase2::flush() {
 	while (!scratch.empty() && isspace(scratch.back())) scratch.pop_back();
 
 
-	if (!scratch.empty()) {
-		parse(classify(), std::move(scratch));
-	}
+	if (!scratch.empty()) parse(classify(), std::move(scratch));
 
 	type = 0;
 	pcount = 0;
@@ -236,20 +234,21 @@ bool phase2::special() {
 	case EVALUATE:
 	case BREAK:
 	case CONTINUE:
+	case EXIT:
 		return true;
 	default:
 		return false;
 	}
 }
 
-void phase2::process(const std::string &line) {
+void phase2::parse(int type, std::string &&s) {
+	if (_then) _then(type, std::move(s));
+}
+
+void phase2::parse(std::string &&line) {
 	
 	//fprintf(stderr, "-> %s\n", line.c_str());
 
-	// still needed?
-	if (line.empty()) { finish(); return; }
-
-
 	int cs;
 	const unsigned char *p = (const unsigned char *)line.data();
 	const unsigned char *pe = p + line.size();
@@ -264,81 +263,19 @@ void phase2::process(const std::string &line) {
 	%% write exec;
 
 	flush();
-	// 2 NLs to make the stack reduce.  harmless if in a multi-line constuct.
-	parse(NL, "");
-	parse(NL, "");
-
-	exec();
+	if (_then) {
+		_then(NL, "");
+		_then(NL, "");
+	}
 }
 
 void phase2::finish() {
-	parse(0, "");
-	exec();
 }
 
-void phase2::parse(int token, std::string &&s) {
-	if (parser) parser->parse(token, std::move(s));
-}
-
-void phase2::exec() {
-
-	if (pipe_to && parser) {
-		command_ptr_vector tmp;
-		for (auto &p : parser->command_queue) {
-			if (p) tmp.emplace_back(std::move(p));
-		}
-		parser->command_queue.clear();
-
-		if (!tmp.empty()) pipe_to(std::move(tmp));
-	}
-	
-}
-
-phase2::phase2() {
-	parser = phase2_parser::make();
-	//parser->trace(stdout, " ] ");
-
-}
-
-void phase2::abort() {
-	parser = nullptr;
-	parser = phase2_parser::make();
-}
-
-#pragma mark - phase2_parser
-
-void phase2_parser::parse_accept() {
-	error = false;
-}
-
-void phase2_parser::parse_failure() {
-	error = false;
-}
-
-void phase2_parser::syntax_error(int yymajor, std::string &yyminor) {
-/*
-	switch (yymajor) {
-	case END:
-		fprintf(stderr, "### MPW Shell - Extra END command.\n");
-		break;
-
-	case RPAREN:
-		fprintf(stderr, "### MPW Shell - Extra ) command.\n");
-		break;
-
-	case ELSE:
-	case ELSE_IF:
-		fprintf(stderr, "### MPW Shell - ELSE must be within IF ... END.\n");
-		break;
-
-	default:
-		fprintf(stderr, "### Parse error near %s\n", yyminor.c_str());
-		break;
-	}
-*/
-
-	
-	fprintf(stderr, "### MPW Shell - Parse error near %s\n", yymajor ? yyminor.c_str() : "EOF");
-	error = true;
+void phase2::reset() {
+
+	type = 0;
+	pcount = 0;
+	scratch.clear();
 }
 

phase3.lemon

@@ -6,19 +6,19 @@
 
 %include {
 
-#include "phase2.h"
+#include "phase3_parser.h"
 #include "command.h"
-#define LEMON_SUPER phase2_parser
-#include "phase2-parser.h"
+#define LEMON_SUPER phase3
 }
 
+
 %code {
 	
-std::unique_ptr<phase2_parser> phase2_parser::make() {
+std::unique_ptr<phase3> phase3::make() {
 	return std::make_unique<yypParser>();
 }
 
-bool phase2_parser::continuation() const {
+bool phase3::continuation() const {
 	yypParser *self = (yypParser *)this;
 
 	for (const auto &e : *self) {
@@ -36,6 +36,43 @@ bool phase2_parser::continuation() const {
 	return false;
 }
 
+
+void phase3::parse_accept() {
+	error = false;
+}
+
+void phase3::parse_failure() {
+	error = false;
+}
+
+void phase3::syntax_error(int yymajor, std::string &yyminor) {
+/*
+	switch (yymajor) {
+	case END:
+		fprintf(stderr, "### MPW Shell - Extra END command.\n");
+		break;
+
+	case RPAREN:
+		fprintf(stderr, "### MPW Shell - Extra ) command.\n");
+		break;
+
+	case ELSE:
+	case ELSE_IF:
+		fprintf(stderr, "### MPW Shell - ELSE must be within IF ... END.\n");
+		break;
+
+	default:
+		fprintf(stderr, "### Parse error near %s\n", yyminor.c_str());
+		break;
+	}
+*/
+
+	
+	fprintf(stderr, "### MPW Shell - Parse error near %s\n", yymajor ? yyminor.c_str() : "EOF");
+	error = true;
+}
+
+
 }
 
 %left PIPE_PIPE AMP_AMP.
@@ -102,6 +139,7 @@ term(RV) ::= COMMAND(C).       { RV = std::make_unique<simple_command>(std::move
 term(RV) ::= EVALUATE(C).      { RV = std::make_unique<evaluate_command>(std::move(C)); }
 term(RV) ::= BREAK(C).         { RV = std::make_unique<break_command>(std::move(C)); }
 term(RV) ::= CONTINUE(C).      { RV = std::make_unique<continue_command>(std::move(C)); }
+term(RV) ::= EXIT(C).          { RV = std::make_unique<exit_command>(std::move(C)); }
 term(C) ::= if_command(C).
 term(C) ::= begin_command(C).
 term(C) ::= paren_command(C).

phase3_parser.h

@@ -0,0 +1,43 @@
+
+#ifndef __phase3_h__
+#define __phase3_h__
+
+#include <string>
+#include <vector>
+#include <memory>
+
+#include "command.h"
+#include <lemon_base.h>
+
+class phase3 : public lemon_base<std::string> {
+
+public:
+	static std::unique_ptr<phase3> make();
+
+	virtual void syntax_error(int yymajor, std::string &yyminor) override final;
+	virtual void parse_accept() override final;
+	virtual void parse_failure() override final;
+
+	bool continuation() const;
+
+	//void parse(int type, std::string &&s) override final;
+
+private:
+
+	phase3(const phase3 &) = delete;
+	phase3(phase3 &&) = delete;
+
+	phase3& operator=(const phase3 &) = delete;
+	phase3& operator=(phase3 &&) = delete;
+
+protected:
+	// these need to be accessible to the lemon-generated parser.
+	phase3() = default;
+
+	command_ptr_vector command_queue;
+	bool error = false;
+
+	friend class mpw_parser;
+};
+
+#endif