New module 'javaversion'.

[gnulib.git] / lib / javaversion.c

diff --git a/lib/javaversion.c b/lib/javaversion.c
new file mode 100644 (file)
index 0000000..a0dea95
--- /dev/null
+++ b/lib/javaversion.c
@@ -0,0 +1,119 @@
+/* Determine the Java version supported by javaexec.
+   Copyright (C) 2006 Free Software Foundation, Inc.
+   Written by Bruno Haible <bruno@clisp.org>, 2006.
+
+   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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */
+
+#ifdef HAVE_CONFIG_H
+# include <config.h>
+#endif
+
+/* Specification.  */
+#include "javaversion.h"
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdio.h>
+
+#if ENABLE_RELOCATABLE
+# include "relocatable.h"
+#else
+# define relocate(pathname) (pathname)
+#endif
+
+#include "javaexec.h"
+#include "pipe.h"
+#include "wait-process.h"
+#include "error.h"
+#include "getline.h"
+#include "gettext.h"
+
+#define _(str) gettext (str)
+
+
+struct locals
+{
+  /* OUT */
+  char *line;
+};
+
+static bool
+execute_and_read_line (const char *progname,
+                      const char *prog_path, char **prog_argv,
+                      void *private_data)
+{
+  struct locals *l = (struct locals *) private_data;
+  pid_t child;
+  int fd[1];
+  FILE *fp;
+  char *line;
+  size_t linesize;
+  size_t linelen;
+  int exitstatus;
+
+  /* Open a pipe to the JVM.  */
+  child = create_pipe_in (progname, prog_path, prog_argv, DEV_NULL, false,
+                         true, false, fd);
+
+  if (child == -1)
+    return false;
+
+  /* Retrieve its result.  */
+  fp = fdopen (fd[0], "r");
+  if (fp == NULL)
+    {
+      error (0, errno, _("fdopen() failed"));
+      return false;
+    }
+
+  line = NULL; linesize = 0;
+  linelen = getline (&line, &linesize, fp);
+  if (linelen == (size_t)(-1))
+    {
+      error (0, 0, _("%s subprocess I/O error"), progname);
+      return false;
+    }
+  if (linelen > 0 && line[linelen - 1] == '\n')
+    line[linelen - 1] = '\0';
+
+  fclose (fp);
+
+  /* Remove zombie process from process list, and retrieve exit status.  */
+  exitstatus = wait_subprocess (child, progname, true, false, true, false);
+  if (exitstatus != 0)
+    {
+      free (line);
+      return false;
+    }
+
+  l->line = line;
+  return false;
+}
+
+char *
+javaexec_version (void)
+{
+  const char *class_name = "javaversion";
+  const char *pkgdatadir = relocate (PKGDATADIR);
+  const char *args[1];
+  struct locals locals;
+
+  args[0] = NULL;
+  locals.line = NULL;
+  execute_java_class (class_name, &pkgdatadir, 1, true, NULL, args,
+                     false, false, execute_and_read_line, &locals);
+
+  return locals.line;
+}