lib/javaexec.c

   1 /* Execute a Java program.
   2    Copyright (C) 2001-2003, 2006-2025 Free Software Foundation, Inc.
   3    Written by Bruno Haible <haible@clisp.cons.org>, 2001.
   4
   5    This program is free software: you can redistribute it and/or modify
   6    it under the terms of the GNU General Public License as published by
   7    the Free Software Foundation, either version 3 of the License, or
   8    (at your option) any later version.
   9
  10    This program is distributed in the hope that it will be useful,
  11    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13    GNU General Public License for more details.
  14
  15    You should have received a copy of the GNU General Public License
  16    along with this program.  If not, see <https://www.gnu.org/licenses/>.  */
  17
  18 #include <config.h>
  19 #include <alloca.h>
  20
  21 /* Specification.  */
  22 #include "javaexec.h"
  23
  24 #include <stdio.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27
  28 #include "execute.h"
  29 #include "classpath.h"
  30 #include "xsetenv.h"
  31 #include "sh-quote.h"
  32 #include "concat-filename.h"
  33 #include "xalloc.h"
  34 #include "xmalloca.h"
  35 #include <error.h>
  36 #include "gettext.h"
  37
  38 #define _(msgid) dgettext ("gnulib", msgid)
  39
  40
  41 /* Survey of Java virtual machines.
  42
  43    A = does it work without CLASSPATH being set
  44    B = does it work with CLASSPATH being set to empty
  45    C = option to set CLASSPATH, other than setting it in the environment
  46    T = test for presence
  47
  48    Program    from         A B  C              T
  49
  50    $JAVA      unknown      N Y  n/a            true
  51    java       JDK 1.1.8    Y Y  -classpath P   java -version 2>/dev/null
  52    jre        JDK 1.1.8    N Y  -classpath P   jre 2>/dev/null; test $? = 1
  53    java       JDK 1.3.0    Y Y  -classpath P   java -version 2>/dev/null
  54
  55    The CLASSPATH is a colon separated list of pathnames. (On Windows: a
  56    semicolon separated list of pathnames.)
  57
  58    We try the Java virtual machines in the following order:
  59      1. getenv ("JAVA"), because the user must be able to override our
  60         preferences,
  61      2. "java", because it is a standard JVM,
  62      3. "jre", comes last because it requires a CLASSPATH environment variable.
  63
  64    We unset the JAVA_HOME environment variable, because a wrong setting of
  65    this variable can confuse the JDK's javac.
  66  */
  67
  68 bool
  69 execute_java_class (const char *class_name,
  70                     const char * const *classpaths,
  71                     unsigned int classpaths_count,
  72                     bool use_minimal_classpath,
  73                     const char *exe_dir,
  74                     const char * const *args,
  75                     bool verbose, bool quiet,
  76                     execute_fn *executer, void *private_data)
  77 {
  78   bool err = false;
  79   unsigned int nargs;
  80   char *old_JAVA_HOME;
  81
  82   /* Count args.  */
  83   {
  84     const char * const *arg;
  85
  86     for (nargs = 0, arg = args; *arg != NULL; nargs++, arg++)
  87      ;
  88   }
  89
  90   /* First, try a class compiled to a native code executable.  */
  91   if (exe_dir != NULL)
  92     {
  93       char *exe_pathname = xconcatenated_filename (exe_dir, class_name, EXEEXT);
  94       char *old_classpath;
  95       const char **argv =
  96         (const char **) xmalloca ((1 + nargs + 1) * sizeof (const char *));
  97       unsigned int i;
  98
  99       /* Set CLASSPATH.  */
 100       old_classpath =
 101         set_classpath (classpaths, classpaths_count, use_minimal_classpath,
 102                        verbose);
 103
 104       argv[0] = exe_pathname;
 105       for (i = 0; i <= nargs; i++)
 106         argv[1 + i] = args[i];
 107
 108       if (verbose)
 109         {
 110           char *command = shell_quote_argv (argv);
 111           printf ("%s\n", command);
 112           free (command);
 113         }
 114
 115       err = executer (class_name, exe_pathname, argv, private_data);
 116
 117       /* Reset CLASSPATH.  */
 118       reset_classpath (old_classpath);
 119
 120       freea (argv);
 121
 122       goto done1;
 123     }
 124
 125   {
 126     const char *java = getenv ("JAVA");
 127     if (java != NULL && java[0] != '\0')
 128       {
 129         /* Because $JAVA may consist of a command and options, we use the
 130            shell.  Because $JAVA has been set by the user, we leave all
 131            all environment variables in place, including JAVA_HOME, and
 132            we don't erase the user's CLASSPATH.  */
 133         char *old_classpath;
 134         unsigned int command_length;
 135         char *command;
 136         const char *argv[4];
 137         const char * const *arg;
 138         char *p;
 139
 140         /* Set CLASSPATH.  */
 141         old_classpath =
 142           set_classpath (classpaths, classpaths_count, false,
 143                          verbose);
 144
 145         command_length = strlen (java);
 146         command_length += 1 + shell_quote_length (class_name);
 147         for (arg = args; *arg != NULL; arg++)
 148           command_length += 1 + shell_quote_length (*arg);
 149         command_length += 1;
 150
 151         command = (char *) xmalloca (command_length);
 152         p = command;
 153         /* Don't shell_quote $JAVA, because it may consist of a command
 154            and options.  */
 155         memcpy (p, java, strlen (java));
 156         p += strlen (java);
 157         *p++ = ' ';
 158         p = shell_quote_copy (p, class_name);
 159         for (arg = args; *arg != NULL; arg++)
 160           {
 161             *p++ = ' ';
 162             p = shell_quote_copy (p, *arg);
 163           }
 164         *p++ = '\0';
 165         /* Ensure command_length was correctly calculated.  */
 166         if (p - command > command_length)
 167           abort ();
 168
 169         if (verbose)
 170           printf ("%s\n", command);
 171
 172         argv[0] = BOURNE_SHELL;
 173         argv[1] = "-c";
 174         argv[2] = command;
 175         argv[3] = NULL;
 176         err = executer (java, BOURNE_SHELL, argv, private_data);
 177
 178         freea (command);
 179
 180         /* Reset CLASSPATH.  */
 181         reset_classpath (old_classpath);
 182
 183         goto done1;
 184       }
 185   }
 186
 187   /* Unset the JAVA_HOME environment variable.  */
 188   old_JAVA_HOME = getenv ("JAVA_HOME");
 189   if (old_JAVA_HOME != NULL)
 190     {
 191       old_JAVA_HOME = xstrdup (old_JAVA_HOME);
 192       unsetenv ("JAVA_HOME");
 193     }
 194
 195   {
 196     static bool java_tested;
 197     static bool java_present;
 198
 199     if (!java_tested)
 200       {
 201         /* Test for presence of java: "java -version 2> /dev/null"  */
 202         const char *argv[3];
 203         int exitstatus;
 204
 205         argv[0] = "java";
 206         argv[1] = "-version";
 207         argv[2] = NULL;
 208         exitstatus = execute ("java", "java", argv, NULL, NULL,
 209                               false, false, true, true,
 210                               true, false, NULL);
 211         java_present = (exitstatus == 0);
 212         java_tested = true;
 213       }
 214
 215     if (java_present)
 216       {
 217         char *old_classpath;
 218         const char **argv =
 219           (const char **) xmalloca ((2 + nargs + 1) * sizeof (const char *));
 220         unsigned int i;
 221
 222         /* Set CLASSPATH.  We don't use the "-classpath ..." option because
 223            in JDK 1.1.x its argument should also contain the JDK's classes.zip,
 224            but we don't know its location.  (In JDK 1.3.0 it would work.)  */
 225         old_classpath =
 226           set_classpath (classpaths, classpaths_count, use_minimal_classpath,
 227                          verbose);
 228
 229         argv[0] = "java";
 230         argv[1] = class_name;
 231         for (i = 0; i <= nargs; i++)
 232           argv[2 + i] = args[i];
 233
 234         if (verbose)
 235           {
 236             char *command = shell_quote_argv (argv);
 237             printf ("%s\n", command);
 238             free (command);
 239           }
 240
 241         err = executer ("java", "java", argv, private_data);
 242
 243         /* Reset CLASSPATH.  */
 244         reset_classpath (old_classpath);
 245
 246         freea (argv);
 247
 248         goto done2;
 249       }
 250   }
 251
 252   {
 253     static bool jre_tested;
 254     static bool jre_present;
 255
 256     if (!jre_tested)
 257       {
 258         /* Test for presence of jre: "jre 2> /dev/null ; test $? = 1"  */
 259         const char *argv[2];
 260         int exitstatus;
 261
 262         argv[0] = "jre";
 263         argv[1] = NULL;
 264         exitstatus = execute ("jre", "jre", argv, NULL, NULL,
 265                               false, false, true, true,
 266                               true, false, NULL);
 267         jre_present = (exitstatus == 0 || exitstatus == 1);
 268         jre_tested = true;
 269       }
 270
 271     if (jre_present)
 272       {
 273         char *old_classpath;
 274         const char **argv =
 275           (const char **) xmalloca ((2 + nargs + 1) * sizeof (const char *));
 276         unsigned int i;
 277
 278         /* Set CLASSPATH.  We don't use the "-classpath ..." option because
 279            in JDK 1.1.x its argument should also contain the JDK's classes.zip,
 280            but we don't know its location.  */
 281         old_classpath =
 282           set_classpath (classpaths, classpaths_count, use_minimal_classpath,
 283                          verbose);
 284
 285         argv[0] = "jre";
 286         argv[1] = class_name;
 287         for (i = 0; i <= nargs; i++)
 288           argv[2 + i] = args[i];
 289
 290         if (verbose)
 291           {
 292             char *command = shell_quote_argv (argv);
 293             printf ("%s\n", command);
 294             free (command);
 295           }
 296
 297         err = executer ("jre", "jre", argv, private_data);
 298
 299         /* Reset CLASSPATH.  */
 300         reset_classpath (old_classpath);
 301
 302         freea (argv);
 303
 304         goto done2;
 305       }
 306   }
 307
 308   if (!quiet)
 309     error (0, 0, _("Java virtual machine not found, try setting $JAVA"));
 310   err = true;
 311
 312  done2:
 313   if (old_JAVA_HOME != NULL)
 314     {
 315       xsetenv ("JAVA_HOME", old_JAVA_HOME, 1);
 316       free (old_JAVA_HOME);
 317     }
 318
 319  done1:
 320   return err;
 321 }