new file mode 100644
--- /dev/null
+++ b/lib/javacomp.c
@@ -0,0 +1,479 @@
+/* Compile a Java program.
+   Copyright (C) 2001-2003 Free Software Foundation, Inc.
+   Written by Bruno Haible <haible@clisp.cons.org>, 2001.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 2, or (at your option)
+   any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program; if not, write to the Free Software Foundation,
+   Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+#include <alloca.h>
+
+/* Specification.  */
+#include "javacomp.h"
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "execute.h"
+#include "pipe.h"
+#include "wait-process.h"
+#include "classpath.h"
+#include "xsetenv.h"
+#include "sh-quote.h"
+#include "safe-read.h"
+#include "xalloc.h"
+#include "xallocsa.h"
+#include "error.h"
+#include "gettext.h"
+
+#define _(str) gettext (str)
+
+
+/* Survey of Java compilers.
+
+   A = does it work without CLASSPATH being set
+   C = option to set CLASSPATH, other than setting it in the environment
+   O = option for optimizing
+   g = option for debugging
+   T = test for presence
+
+   Program  from        A  C               O  g  T
+
+   $JAVAC   unknown     N  n/a            -O -g  true
+   gcj -C   GCC 3.2     Y  --classpath=P  -O -g  gcj --version | sed -e 's,^[^0-9]*,,' -e 1q | sed -e '/^3\.[01]/d' | grep '^[3-9]' >/dev/null
+   javac    JDK 1.1.8   Y  -classpath P   -O -g  javac 2>/dev/null; test $? = 1
+   javac    JDK 1.3.0   Y  -classpath P   -O -g  javac 2>/dev/null; test $? -le 2
+   jikes    Jikes 1.14  N  -classpath P   -O -g  jikes 2>/dev/null; test $? = 1
+
+   All compilers support the option "-d DIRECTORY" for the base directory
+   of the classes to be written.
+
+   The CLASSPATH is a colon separated list of pathnames. (On Windows: a
+   semicolon separated list of pathnames.)
+
+   We try the Java compilers in the following order:
+     1. getenv ("JAVAC"), because the user must be able to override our
+	preferences,
+     2. "gcj -C", because it is a completely free compiler,
+     3. "javac", because it is a standard compiler,
+     4. "jikes", comes last because it has some deviating interpretation
+	of the Java Language Specification and because it requires a
+	CLASSPATH environment variable.
+
+   We unset the JAVA_HOME environment variable, because a wrong setting of
+   this variable can confuse the JDK's javac.
+ */
+
+bool
+compile_java_class (const char * const *java_sources,
+		    unsigned int java_sources_count,
+		    const char * const *classpaths,
+		    unsigned int classpaths_count,
+		    const char *directory,
+		    bool optimize, bool debug,
+		    bool use_minimal_classpath,
+		    bool verbose)
+{
+  bool err = false;
+  char *old_JAVA_HOME;
+
+  {
+    const char *javac = getenv ("JAVAC");
+    if (javac != NULL && javac[0] != '\0')
+      {
+	/* Because $JAVAC may consist of a command and options, we use the
+	   shell.  Because $JAVAC has been set by the user, we leave all
+	   all environment variables in place, including JAVA_HOME, and
+	   we don't erase the user's CLASSPATH.  */
+	char *old_classpath;
+	unsigned int command_length;
+	char *command;
+	char *argv[4];
+	int exitstatus;
+	unsigned int i;
+	char *p;
+
+	/* Set CLASSPATH.  */
+	old_classpath =
+	  set_classpath (classpaths, classpaths_count, false,
+			 verbose);
+
+	command_length = strlen (javac);
+	if (optimize)
+	  command_length += 3;
+	if (debug)
+	  command_length += 3;
+	if (directory != NULL)
+	  command_length += 4 + shell_quote_length (directory);
+	for (i = 0; i < java_sources_count; i++)
+	  command_length += 1 + shell_quote_length (java_sources[i]);
+	command_length += 1;
+
+	command = (char *) xallocsa (command_length);
+	p = command;
+	/* Don't shell_quote $JAVAC, because it may consist of a command
+	   and options.  */
+	memcpy (p, javac, strlen (javac));
+	p += strlen (javac);
+	if (optimize)
+	  {
+	    memcpy (p, " -O", 3);
+	    p += 3;
+	  }
+	if (debug)
+	  {
+	    memcpy (p, " -g", 3);
+	    p += 3;
+	  }
+	if (directory != NULL)
+	  {
+	    memcpy (p, " -d ", 4);
+	    p += 4;
+	    p = shell_quote_copy (p, directory);
+	  }
+	for (i = 0; i < java_sources_count; i++)
+	  {
+	    *p++ = ' ';
+	    p = shell_quote_copy (p, java_sources[i]);
+	  }
+	*p++ = '\0';
+	/* Ensure command_length was correctly calculated.  */
+	if (p - command > command_length)
+	  abort ();
+
+	if (verbose)
+	  printf ("%s\n", command);
+
+	argv[0] = "/bin/sh";
+	argv[1] = "-c";
+	argv[2] = command;
+	argv[3] = NULL;
+	exitstatus = execute (javac, "/bin/sh", argv, false, false, false,
+			      false, true, true);
+	err = (exitstatus != 0);
+
+	freesa (command);
+
+	/* Reset CLASSPATH.  */
+	reset_classpath (old_classpath);
+
+	goto done1;
+      }
+  }
+
+  /* Unset the JAVA_HOME environment variable.  */
+  old_JAVA_HOME = getenv ("JAVA_HOME");
+  if (old_JAVA_HOME != NULL)
+    {
+      old_JAVA_HOME = xstrdup (old_JAVA_HOME);
+      unsetenv ("JAVA_HOME");
+    }
+
+  {
+    static bool gcj_tested;
+    static bool gcj_present;
+
+    if (!gcj_tested)
+      {
+	/* Test for presence of gcj:
+	   "gcj --version 2> /dev/null | \
+	    sed -e 's,^[^0-9]*,,' -e 1q | \
+	    sed -e '/^3\.[01]/d' | grep '^[3-9]' > /dev/null"  */
+	char *argv[3];
+	pid_t child;
+	int fd[1];
+	int exitstatus;
+
+	argv[0] = "gcj";
+	argv[1] = "--version";
+	argv[2] = NULL;
+	child = create_pipe_in ("gcj", "gcj", argv, DEV_NULL, true, true,
+				false, fd);
+	gcj_present = false;
+	if (child != -1)
+	  {
+	    /* Read the subprocess output, drop all lines except the first,
+	       drop all characters before the first digit, and test whether
+	       the remaining string starts with a digit >= 3, but not with
+	       "3.0" or "3.1".  */
+	    char c[3];
+	    size_t count = 0;
+
+	    while (safe_read (fd[0], &c[count], 1) > 0)
+	      {
+		if (c[count] == '\n')
+		  break;
+		if (count == 0)
+		  {
+		    if (!(c[0] >= '0' && c[0] <= '9'))
+		      continue;
+		    gcj_present = (c[0] >= '3');
+		  }
+		count++;
+		if (count == 3)
+		  {
+		    if (c[0] == '3' && c[1] == '.'
+			&& (c[2] == '0' || c[2] == '1'))
+		      gcj_present = false;
+		    break;
+		  }
+	      }
+	    while (safe_read (fd[0], &c[0], 1) > 0)
+	      ;
+
+	    close (fd[0]);
+
+	    /* Remove zombie process from process list, and retrieve exit
+	       status.  */
+	    exitstatus =
+	      wait_subprocess (child, "gcj", false, true, true, false);
+	    if (exitstatus != 0)
+	      gcj_present = false;
+	  }
+	gcj_tested = true;
+      }
+
+    if (gcj_present)
+      {
+	char *old_classpath;
+	unsigned int argc;
+	char **argv;
+	char **argp;
+	int exitstatus;
+	unsigned int i;
+
+	/* Set CLASSPATH.  We could also use the --CLASSPATH=... option
+	   of gcj.  Note that --classpath=... option is different: its
+	   argument should also contain gcj's libgcj.jar, but we don't
+	   know its location.  */
+	old_classpath =
+	  set_classpath (classpaths, classpaths_count, use_minimal_classpath,
+			 verbose);
+
+	argc =
+	  2 + (optimize ? 1 : 0) + (debug ? 1 : 0) + (directory != NULL ? 2 : 0)
+	  + java_sources_count;
+	argv = (char **) xallocsa ((argc + 1) * sizeof (char *));
+
+	argp = argv;
+	*argp++ = "gcj";
+	*argp++ = "-C";
+	if (optimize)
+	  *argp++ = "-O";
+	if (debug)
+	  *argp++ = "-g";
+	if (directory != NULL)
+	  {
+	    *argp++ = "-d";
+	    *argp++ = (char *) directory;
+	  }
+	for (i = 0; i < java_sources_count; i++)
+	  *argp++ = (char *) java_sources[i];
+	*argp = NULL;
+	/* Ensure argv length was correctly calculated.  */
+	if (argp - argv != argc)
+	  abort ();
+
+	if (verbose)
+	  {
+	    char *command = shell_quote_argv (argv);
+	    printf ("%s\n", command);
+	    free (command);
+	  }
+
+	exitstatus = execute ("gcj", "gcj", argv, false, false, false, false,
+			      true, true);
+	err = (exitstatus != 0);
+
+	freesa (argv);
+
+	/* Reset CLASSPATH.  */
+	reset_classpath (old_classpath);
+
+	goto done2;
+      }
+  }
+
+  {
+    static bool javac_tested;
+    static bool javac_present;
+
+    if (!javac_tested)
+      {
+	/* Test for presence of javac: "javac 2> /dev/null ; test $? -le 2"  */
+	char *argv[2];
+	int exitstatus;
+
+	argv[0] = "javac";
+	argv[1] = NULL;
+	exitstatus = execute ("javac", "javac", argv, false, false, true, true,
+			      true, false);
+	javac_present = (exitstatus == 0 || exitstatus == 1 || exitstatus == 2);
+	javac_tested = true;
+      }
+
+    if (javac_present)
+      {
+	char *old_classpath;
+	unsigned int argc;
+	char **argv;
+	char **argp;
+	int exitstatus;
+	unsigned int i;
+
+	/* Set CLASSPATH.  We don't use the "-classpath ..." option because
+	   in JDK 1.1.x its argument should also contain the JDK's classes.zip,
+	   but we don't know its location.  (In JDK 1.3.0 it would work.)  */
+	old_classpath =
+	  set_classpath (classpaths, classpaths_count, use_minimal_classpath,
+			 verbose);
+
+	argc =
+	  1 + (optimize ? 1 : 0) + (debug ? 1 : 0) + (directory != NULL ? 2 : 0)
+	  + java_sources_count;
+	argv = (char **) xallocsa ((argc + 1) * sizeof (char *));
+
+	argp = argv;
+	*argp++ = "javac";
+	if (optimize)
+	  *argp++ = "-O";
+	if (debug)
+	  *argp++ = "-g";
+	if (directory != NULL)
+	  {
+	    *argp++ = "-d";
+	    *argp++ = (char *) directory;
+	  }
+	for (i = 0; i < java_sources_count; i++)
+	  *argp++ = (char *) java_sources[i];
+	*argp = NULL;
+	/* Ensure argv length was correctly calculated.  */
+	if (argp - argv != argc)
+	  abort ();
+
+	if (verbose)
+	  {
+	    char *command = shell_quote_argv (argv);
+	    printf ("%s\n", command);
+	    free (command);
+	  }
+
+	exitstatus = execute ("javac", "javac", argv, false, false, false,
+			      false, true, true);
+	err = (exitstatus != 0);
+
+	freesa (argv);
+
+	/* Reset CLASSPATH.  */
+	reset_classpath (old_classpath);
+
+	goto done2;
+      }
+  }
+
+  {
+    static bool jikes_tested;
+    static bool jikes_present;
+
+    if (!jikes_tested)
+      {
+	/* Test for presence of jikes: "jikes 2> /dev/null ; test $? = 1"  */
+	char *argv[2];
+	int exitstatus;
+
+	argv[0] = "jikes";
+	argv[1] = NULL;
+	exitstatus = execute ("jikes", "jikes", argv, false, false, true, true,
+			      true, false);
+	jikes_present = (exitstatus == 0 || exitstatus == 1);
+	jikes_tested = true;
+      }
+
+    if (jikes_present)
+      {
+	char *old_classpath;
+	unsigned int argc;
+	char **argv;
+	char **argp;
+	int exitstatus;
+	unsigned int i;
+
+	/* Set CLASSPATH.  We could also use the "-classpath ..." option.
+	   Since jikes doesn't come with its own standard library, it
+	   needs a classes.zip or rt.jar or libgcj.jar in the CLASSPATH.
+	   To increase the chance of success, we reuse the current CLASSPATH
+	   if the user has set it.  */
+	old_classpath =
+	  set_classpath (classpaths, classpaths_count, false,
+			 verbose);
+
+	argc =
+	  1 + (optimize ? 1 : 0) + (debug ? 1 : 0) + (directory != NULL ? 2 : 0)
+	  + java_sources_count;
+	argv = (char **) xallocsa ((argc + 1) * sizeof (char *));
+
+	argp = argv;
+	*argp++ = "jikes";
+	if (optimize)
+	  *argp++ = "-O";
+	if (debug)
+	  *argp++ = "-g";
+	if (directory != NULL)
+	  {
+	    *argp++ = "-d";
+	    *argp++ = (char *) directory;
+	  }
+	for (i = 0; i < java_sources_count; i++)
+	  *argp++ = (char *) java_sources[i];
+	*argp = NULL;
+	/* Ensure argv length was correctly calculated.  */
+	if (argp - argv != argc)
+	  abort ();
+
+	if (verbose)
+	  {
+	    char *command = shell_quote_argv (argv);
+	    printf ("%s\n", command);
+	    free (command);
+	  }
+
+	exitstatus = execute ("jikes", "jikes", argv, false, false, false,
+			      false, true, true);
+	err = (exitstatus != 0);
+
+	freesa (argv);
+
+	/* Reset CLASSPATH.  */
+	reset_classpath (old_classpath);
+
+	goto done2;
+      }
+  }
+
+  error (0, 0, _("Java compiler not found, try installing gcj or set $JAVAC"));
+  err = true;
+
+ done2:
+  if (old_JAVA_HOME != NULL)
+    {
+      xsetenv ("JAVA_HOME", old_JAVA_HOME, 1);
+      free (old_JAVA_HOME);
+    }
+
+ done1:
+  return err;
+}