Noux: add support for executing shell scripts

With this patch Noux recognizes the '#!' character sequence in executable
files and executes the specified interpreter.

Fixes #255.

ports/run/noux_shell_script.run

@@ -0,0 +1,171 @@
+set build_components {
+	core init drivers/timer noux/minimal lib/libc_noux
+	drivers/framebuffer drivers/pci drivers/input
+	server/terminal server/ram_fs
+	test/libports/ncurses
+}
+
+#
+# Build Noux packages only once
+#
+set noux_pkgs {bash coreutils make}
+
+foreach pkg $noux_pkgs {
+	lappend_if [expr ![file exists bin/$pkg]] build_components noux-pkg/$pkg }
+
+build $build_components
+
+# strip all binaries prior archiving
+set find_args ""
+foreach pkg $noux_pkgs { append find_args " bin/$pkg/" }
+exec sh -c "find $find_args -type f | (xargs [cross_dev_prefix]strip || true) 2>/dev/null"
+
+# create '/bin/sh' symlink
+exec sh -c "ln -sf bash bin/bash/bin/sh"
+
+foreach pkg $noux_pkgs {
+	exec tar cfv bin/$pkg.tar -h -C bin/$pkg . }
+
+create_boot_directory
+
+append config {
+	<config verbose="yes">
+		<parent-provides>
+			<service name="ROM"/>
+			<service name="LOG"/>
+			<service name="CAP"/>
+			<service name="RAM"/>
+			<service name="RM"/>
+			<service name="CPU"/>
+			<service name="PD"/>
+			<service name="IRQ"/>
+			<service name="IO_PORT"/>
+			<service name="IO_MEM"/>
+			<service name="SIGNAL"/>
+		</parent-provides>
+		<default-route>
+			<any-service> <any-child/> <parent/> </any-service>
+		</default-route>
+		<start name="timer">
+			<resource name="RAM" quantum="1M"/>
+			<provides><service name="Timer"/></provides>
+		</start> }
+
+append_if [have_spec sdl] config {
+	<start name="fb_sdl">
+		<resource name="RAM" quantum="4M"/>
+		<provides>
+			<service name="Input"/>
+			<service name="Framebuffer"/>
+		</provides>
+	</start>}
+
+append_if [have_spec pci] config {
+	<start name="pci_drv">
+		<resource name="RAM" quantum="1M"/>
+		<provides><service name="PCI"/></provides>
+	</start>}
+
+append_if [have_spec vesa] config {
+	<start name="vesa_drv">
+		<resource name="RAM" quantum="1M"/>
+		<provides><service name="Framebuffer"/></provides>
+	</start>}
+
+append_if [have_spec pl11x] config {
+	<start name="pl11x_drv">
+		<resource name="RAM" quantum="2M"/>
+		<provides><service name="Framebuffer"/></provides>
+	</start>}
+
+append_if [have_spec ps2] config {
+	<start name="ps2_drv">
+		<resource name="RAM" quantum="1M"/>
+		<provides><service name="Input"/></provides>
+	</start> }
+
+append config {
+	<start name="terminal">
+		<resource name="RAM" quantum="2M"/>
+		<provides><service name="Terminal"/></provides>
+		<config>
+			<keyboard layout="de"/>
+		</config>
+	</start>
+	<start name="ram_fs">
+		<resource name="RAM" quantum="10M"/>
+		<provides><service name="File_system"/></provides>
+		<config>
+
+			<!-- preload RAM file system with some ROM images -->
+			<content>
+				<dir name="home">
+					<dir name="user">
+						<inline name=".bash_profile">/home/test_script correct</inline>
+						<inline name="test_script">#!/bin/make -f
+wrong:
+	@echo "wrong target"
+correct:
+	@echo "correct target"
+						</inline>
+					</dir>
+				</dir>
+			</content>
+
+			<!-- constrain sessions according to their labels -->
+			<policy label="noux -> root" root="/" />
+			<policy label="noux -> home" root="/home/user" writeable="yes" />
+		</config>
+	</start>
+	<start name="noux">
+		<resource name="RAM" quantum="1G" />
+		<config>
+			<fstab> }
+
+foreach pkg $noux_pkgs {
+	append config "				<tar name=\"$pkg.tar\" />" }
+
+append config {
+				<dir name="home"> <fs label="home" /> </dir>
+				<dir name="ram"> <fs label="root" /> </dir>
+
+			</fstab>
+			<start name="/bin/bash">
+				<env name="TERM" value="linux" />
+				<env name="HOME" value="/home" />
+				<arg value="--login" />
+			</start>
+		</config>
+	</start>
+</config>
+}
+
+install_config $config
+
+
+#
+# Boot modules
+#
+
+# generic modules
+set boot_modules {
+	core init timer ld.lib.so noux terminal ram_fs
+	libc.lib.so libm.lib.so libc_noux.lib.so ncurses.lib.so }
+
+foreach pkg $noux_pkgs {
+	lappend boot_modules "$pkg.tar" }
+
+# platform-specific modules
+lappend_if [have_spec linux] boot_modules fb_sdl
+lappend_if [have_spec pci]   boot_modules pci_drv
+lappend_if [have_spec vesa]  boot_modules vesa_drv
+lappend_if [have_spec ps2]   boot_modules ps2_drv
+lappend_if [have_spec pl11x] boot_modules pl11x_drv
+
+build_boot_image $boot_modules
+
+append qemu_args " -m 300 "
+
+run_genode_until forever
+
+exec rm bin/bash.tar

ports/src/noux/child_env.h

@@ -0,0 +1,191 @@
+/*
+ * \brief  Noux child environment
+ * \author Christian Prochaska
+ * \author Norman Feske
+ * \date   2012-07-19
+ */
+
+/*
+ * Copyright (C) 2012 Genode Labs GmbH
+ *
+ * This file is part of the Genode OS framework, which is distributed
+ * under the terms of the GNU General Public License version 2.
+ */
+
+#ifndef _NOUX__CHILD_ENV_H_
+#define _NOUX__CHILD_ENV_H_
+
+/* Genode includes */
+#include <util/string.h>
+
+/* Noux includes */
+#include <noux_session/sysio.h>
+#include <range_checked_index.h>
+
+namespace Noux {
+
+	using namespace Genode;
+
+	/**
+	 * \param ARGS_SIZE  size of the argument buffer given
+	 *                   to the constructor
+	 */
+	template <size_t ARGS_SIZE>
+	class Child_env
+	{
+		private:
+
+			enum { MAX_LEN_INTERPRETER_LINE = 128 };
+
+			char const *_binary_name;
+			char        _args[ARGS_SIZE + MAX_LEN_INTERPRETER_LINE];
+			char        _env[Sysio::ENV_MAX_LEN];
+
+			/**
+			 * Deserialize environment variable buffer into a
+			 * null-terminated string. The source env buffer contains a
+			 * list of strings separated by single 0 characters. Each
+			 * string has the form "name=value" (w/o the quotes). The end
+			 * of the list is marked by an additional 0 character. The
+			 * resulting string is a null-terminated string containing a
+			 * comma-separated list of environment variables.
+			 */
+			void _process_env(Sysio::Env env)
+			{
+				/**
+				 * In the following loop, 'i' is the index into the source
+				 * buffer, 'j' is the index into the destination buffer, 'env'
+				 * is the destination.
+				 */
+				for (unsigned i = 0, j = 0; i < Sysio::ENV_MAX_LEN && env[i]; )
+				{
+					char const *src = &env[i];
+
+					/* prepend a comma in front of each entry except for the first one */
+					if (i) {
+						snprintf(env + j, sizeof(env) - j, ",");
+						j++;
+					}
+
+					snprintf(env + j, sizeof(env) - j, "%s", src);
+
+					/* skip null separator in source string */
+					i += strlen(src) + 1;
+					j += strlen(src);
+				}
+			}
+
+
+			/**
+			 * Handle the case that the given binary needs an interpreter
+			 */
+			void _process_binary_name_and_args(const char *binary_name,
+			                                   Dataspace_capability binary_ds,
+			                                   const char *args)
+			{
+				bool interpretable = true;
+
+				const size_t binary_size = Dataspace_client(binary_ds).size();
+
+				if (binary_size < 4)
+					interpretable = false;
+
+				const char *binary_addr = 0;
+				if (interpretable)
+					try {
+						binary_addr = Genode::env()->rm_session()->attach(binary_ds);
+					} catch(...)  {
+						PWRN("could not attach dataspace");
+						interpretable = false;
+					}
+
+				if (interpretable &&
+				    ((binary_addr[0] != '#') || (binary_addr[1] != '!')))
+					interpretable = false;
+
+				if (!interpretable) {
+					Genode::env()->rm_session()->detach(binary_addr);
+					_binary_name = binary_name;
+					Genode::memcpy(_args, args, ARGS_SIZE);
+					return;
+				}
+
+				/* find end of line */
+				Range_checked_index<unsigned int>
+					eol(2, min(binary_size, MAX_LEN_INTERPRETER_LINE));
+
+				try {
+					while (binary_addr[eol] != '\n') eol++;
+				} catch (Index_out_of_range) { }
+
+				/* skip leading spaces */
+				Range_checked_index<unsigned int>
+					interpreter_line_cursor(2, eol);
+
+				try {
+					while (binary_addr[interpreter_line_cursor] == ' ')
+						interpreter_line_cursor++;
+				} catch (Index_out_of_range) { }
+
+				/* no interpreter name found */
+				if (interpreter_line_cursor == eol)
+					throw Child::Binary_does_not_exist();
+
+				int interpreter_name_start = interpreter_line_cursor;
+
+				/* find end of interpreter name */
+				try {
+					while (binary_addr[interpreter_line_cursor] != ' ')
+						interpreter_line_cursor++;
+				} catch (Index_out_of_range) { }
+
+				size_t interpreter_name_len =
+					interpreter_line_cursor - interpreter_name_start;
+
+				/* copy interpreter name into argument buffer */
+				unsigned int args_buf_cursor = 0;
+				Genode::strncpy(&_args[args_buf_cursor],
+								&binary_addr[interpreter_name_start],
+								interpreter_name_len + 1);
+				_binary_name = &_args[args_buf_cursor];
+				args_buf_cursor += interpreter_name_len + 1;
+
+				/* skip more spaces */
+				try {
+					while (binary_addr[interpreter_line_cursor] == ' ')
+						interpreter_line_cursor++;
+				} catch (Index_out_of_range) { }
+
+				/* append interpreter arguments to argument buffer */
+				size_t interpreter_args_len = eol - interpreter_line_cursor;
+				Genode::strncpy(&_args[args_buf_cursor],
+				                &binary_addr[interpreter_line_cursor],
+				                interpreter_args_len + 1);
+				args_buf_cursor += interpreter_args_len + 1;
+
+				/* append script arguments to argument buffer */
+				Genode::memcpy(&_args[args_buf_cursor],
+				               args, ARGS_SIZE);
+
+				Genode::env()->rm_session()->detach(binary_addr);
+			}
+
+		public:
+
+			Child_env(const char *binary_name, Dataspace_capability binary_ds,
+			          const char *args, Sysio::Env env)
+			{
+				_process_env(env);
+				_process_binary_name_and_args(binary_name, binary_ds, args);
+			}
+
+			char const *binary_name() const { return _binary_name; }
+
+			Args args() { return Args(_args, sizeof(_args)); }
+
+			char const *env() const { return _env; }
+	};
+
+}
+
+#endif /* _NOUX__CHILD_ENV_H_ */

ports/src/noux/main.cc

@@ -45,6 +45,7 @@
 
 /* Noux includes */
 #include <child.h>
+#include <child_env.h>
 #include <vfs_io_channel.h>
 #include <terminal_io_channel.h>
 #include <dummy_input_io_channel.h>
@@ -203,46 +204,23 @@ bool Noux::Child::syscall(Noux::Session::Syscall sc)
 			{
 				Absolute_path absolute_path(_sysio->execve_in.filename, _env.pwd());
 
-				/*
+				Dataspace_capability binary_ds = _root_dir->dataspace(absolute_path.base());
-				 * Deserialize environment variable buffer into a
-				 * null-terminated string. The source env buffer contains a
-				 * list of strings separated by single 0 characters. Each
-				 * string has the form "name=value" (w/o the quotes). The end
-				 * of the list is marked by an additional 0 character. The
-				 * resulting string is a null-terminated string containing a
-				 * comma-separated list of environment variables.
-				 *
-				 * In the following loop, 'i' is the index into the source
-				 * buffer, 'j' is the index into the destination buffer, 'env'
-				 * is the destination.
-				 */
-				char env[Sysio::ENV_MAX_LEN];
-				for (unsigned i = 0, j = 0; i < Sysio::ENV_MAX_LEN && _sysio->execve_in.env[i]; )
-				{
-					char const *src = &_sysio->execve_in.env[i];
 
-					/* prepend a comma in front of each entry except for the first one */
+				if (!binary_ds.valid())
-					if (i) {
+					throw Child::Binary_does_not_exist();
-						snprintf(env + j, sizeof(env) - j, ",");
-						j++;
-					}
 
-					snprintf(env + j, sizeof(env) - j, "%s", src);
+				Child_env<sizeof(_sysio->execve_in.args)> child_env(
-
+				    absolute_path.base(), binary_ds, _sysio->execve_in.args,
-					/* skip null separator in source string */
+				    _sysio->execve_in.env);
-					i += strlen(src) + 1;
-					j += strlen(src);
-				}
 
 				try {
-					Child *child = new Child(absolute_path.base(),
+					Child *child = new Child(child_env.binary_name(),
 					                         parent(),
 					                         pid(),
 					                         _sig_rec,
 					                         _root_dir,
-					                         Args(_sysio->execve_in.args,
+					                         child_env.args(),
-					                              sizeof(_sysio->execve_in.args)),
+					                         child_env.env(),
-					                         env,
 					                         _env.pwd(),
 					                         _cap_session,
 					                         _parent_services,