1 /*

     2  * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved.

     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     4  *

     5  * This code is free software; you can redistribute it and/or modify it

     6  * under the terms of the GNU General Public License version 2 only, as

     7  * published by the Free Software Foundation.  Oracle designates this

     8  * particular file as subject to the "Classpath" exception as provided

     9  * by Oracle in the LICENSE file that accompanied this code.

    10  *

    11  * This code is distributed in the hope that it will be useful, but WITHOUT

    12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    14  * version 2 for more details (a copy is included in the LICENSE file that

    15  * accompanied this code).

    16  *

    17  * You should have received a copy of the GNU General Public License version

    18  * 2 along with this work; if not, write to the Free Software Foundation,

    19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    20  *

    21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    22  * or visit www.oracle.com if you need additional information or have any

    23  * questions.

    24  */

    25 #include "java.h"

    26 

    27 /*

    28  * If app is "/foo/bin/javac", or "/foo/bin/sparcv9/javac" then put

    29  * "/foo" into buf.

    30  */

    31 jboolean

    32 GetApplicationHome(char *buf, jint bufsize)

    33 {

    34     const char *execname = GetExecName();

    35     if (execname != NULL) {

    36         JLI_Snprintf(buf, bufsize, "%s", execname);

    37         buf[bufsize-1] = '\0';

    38     } else {

    39         return JNI_FALSE;

    40     }

    41 

    42     if (JLI_StrRChr(buf, '/') == 0) {

    43         buf[0] = '\0';

    44         return JNI_FALSE;

    45     }

    46     *(JLI_StrRChr(buf, '/')) = '\0';    /* executable file      */

    47     if (JLI_StrLen(buf) < 4 || JLI_StrRChr(buf, '/') == 0) {

    48         buf[0] = '\0';

    49         return JNI_FALSE;

    50     }

    51     if (JLI_StrCmp("/bin", buf + JLI_StrLen(buf) - 4) != 0)

    52         *(JLI_StrRChr(buf, '/')) = '\0';        /* sparcv9 or amd64     */

    53     if (JLI_StrLen(buf) < 4 || JLI_StrCmp("/bin", buf + JLI_StrLen(buf) - 4) != 0) {

    54         buf[0] = '\0';

    55         return JNI_FALSE;

    56     }

    57     *(JLI_StrRChr(buf, '/')) = '\0';    /* bin                  */

    58 

    59     return JNI_TRUE;

    60 }

    61 /*

    62  * Return true if the named program exists

    63  */

    64 static int

    65 ProgramExists(char *name)

    66 {

    67     struct stat sb;

    68     if (stat(name, &sb) != 0) return 0;

    69     if (S_ISDIR(sb.st_mode)) return 0;

    70     return (sb.st_mode & S_IEXEC) != 0;

    71 }

    72 

    73 /*

    74  * Find a command in a directory, returning the path.

    75  */

    76 static char *

    77 Resolve(char *indir, char *cmd)

    78 {

    79     char name[PATH_MAX + 2], *real;

    80 

    81     if ((JLI_StrLen(indir) + JLI_StrLen(cmd) + 1)  > PATH_MAX) return 0;

    82     JLI_Snprintf(name, sizeof(name), "%s%c%s", indir, FILE_SEPARATOR, cmd);

    83     if (!ProgramExists(name)) return 0;

    84     real = JLI_MemAlloc(PATH_MAX + 2);

    85     if (!realpath(name, real))

    86         JLI_StrCpy(real, name);

    87     return real;

    88 }

    89 

    90 /*

    91  * Find a path for the executable

    92  */

    93 char *

    94 FindExecName(char *program)

    95 {

    96     char cwdbuf[PATH_MAX+2];

    97     char *path;

    98     char *tmp_path;

    99     char *f;

   100     char *result = NULL;

   101 

   102     /* absolute path? */

   103     if (*program == FILE_SEPARATOR ||

   104         (FILE_SEPARATOR=='\\' && JLI_StrRChr(program, ':')))

   105         return Resolve("", program+1);

   106 

   107     /* relative path? */

   108     if (JLI_StrRChr(program, FILE_SEPARATOR) != 0) {

   109         char buf[PATH_MAX+2];

   110         return Resolve(getcwd(cwdbuf, sizeof(cwdbuf)), program);

   111     }

   112 

   113     /* from search path? */

   114     path = getenv("PATH");

   115     if (!path || !*path) path = ".";

   116     tmp_path = JLI_MemAlloc(JLI_StrLen(path) + 2);

   117     JLI_StrCpy(tmp_path, path);

   118 

   119     for (f=tmp_path; *f && result==0; ) {

   120         char *s = f;

   121         while (*f && (*f != PATH_SEPARATOR)) ++f;

   122         if (*f) *f++ = 0;

   123         if (*s == FILE_SEPARATOR)

   124             result = Resolve(s, program);

   125         else {

   126             /* relative path element */

   127             char dir[2*PATH_MAX];

   128             JLI_Snprintf(dir, sizeof(dir), "%s%c%s", getcwd(cwdbuf, sizeof(cwdbuf)),

   129                     FILE_SEPARATOR, s);

   130             result = Resolve(dir, program);

   131         }

   132         if (result != 0) break;

   133     }

   134 

   135     JLI_MemFree(tmp_path);

   136     return result;

   137 }

   138 

   139 void JLI_ReportErrorMessage(const char* fmt, ...) {

   140     va_list vl;

   141     va_start(vl, fmt);

   142     vfprintf(stderr, fmt, vl);

   143     fprintf(stderr, "\n");

   144     va_end(vl);

   145 }

   146 

   147 void JLI_ReportErrorMessageSys(const char* fmt, ...) {

   148     va_list vl;

   149     char *emsg;

   150 

   151     /*

   152      * TODO: its safer to use strerror_r but is not available on

   153      * Solaris 8. Until then....

   154      */

   155     emsg = strerror(errno);

   156     if (emsg != NULL) {

   157         fprintf(stderr, "%s\n", emsg);

   158     }

   159 

   160     va_start(vl, fmt);

   161     vfprintf(stderr, fmt, vl);

   162     fprintf(stderr, "\n");

   163     va_end(vl);

   164 }

   165 

   166 void  JLI_ReportExceptionDescription(JNIEnv * env) {

   167   (*env)->ExceptionDescribe(env);

   168 }

   169 

   170 /*

   171  *      Since using the file system as a registry is a bit risky, perform

   172  *      additional sanity checks on the identified directory to validate

   173  *      it as a valid jre/sdk.

   174  *

   175  *      Return 0 if the tests fail; otherwise return non-zero (true).

   176  *

   177  *      Note that checking for anything more than the existence of an

   178  *      executable object at bin/java relative to the path being checked

   179  *      will break the regression tests.

   180  */

   181 static int

   182 CheckSanity(char *path, char *dir)

   183 {

   184     char    buffer[PATH_MAX];

   185 

   186     if (JLI_StrLen(path) + JLI_StrLen(dir) + 11 > PATH_MAX)

   187         return (0);     /* Silently reject "impossibly" long paths */

   188 

   189     JLI_Snprintf(buffer, sizeof(buffer), "%s/%s/bin/java", path, dir);

   190     return ((access(buffer, X_OK) == 0) ? 1 : 0);

   191 }

   192 

   193 /*

   194  *      Determine if there is an acceptable JRE in the directory dirname.

   195  *      Upon locating the "best" one, return a fully qualified path to

   196  *      it. "Best" is defined as the most advanced JRE meeting the

   197  *      constraints contained in the manifest_info. If no JRE in this

   198  *      directory meets the constraints, return NULL.

   199  *

   200  *      Note that we don't check for errors in reading the directory

   201  *      (which would be done by checking errno).  This is because it

   202  *      doesn't matter if we get an error reading the directory, or

   203  *      we just don't find anything interesting in the directory.  We

   204  *      just return NULL in either case.

   205  *

   206  *      The historical names of j2sdk and j2re were changed to jdk and

   207  *      jre respecively as part of the 1.5 rebranding effort.  Since the

   208  *      former names are legacy on Linux, they must be recognized for

   209  *      all time.  Fortunately, this is a minor cost.

   210  */

   211 static char

   212 *ProcessDir(manifest_info *info, char *dirname)

   213 {

   214     DIR     *dirp;

   215     struct dirent *dp;

   216     char    *best = NULL;

   217     int     offset;

   218     int     best_offset = 0;

   219     char    *ret_str = NULL;

   220     char    buffer[PATH_MAX];

   221 

   222     if ((dirp = opendir(dirname)) == NULL)

   223         return (NULL);

   224 

   225     do {

   226         if ((dp = readdir(dirp)) != NULL) {

   227             offset = 0;

   228             if ((JLI_StrNCmp(dp->d_name, "jre", 3) == 0) ||

   229                 (JLI_StrNCmp(dp->d_name, "jdk", 3) == 0))

   230                 offset = 3;

   231             else if (JLI_StrNCmp(dp->d_name, "j2re", 4) == 0)

   232                 offset = 4;

   233             else if (JLI_StrNCmp(dp->d_name, "j2sdk", 5) == 0)

   234                 offset = 5;

   235             if (offset > 0) {

   236                 if ((JLI_AcceptableRelease(dp->d_name + offset,

   237                     info->jre_version)) && CheckSanity(dirname, dp->d_name))

   238                     if ((best == NULL) || (JLI_ExactVersionId(

   239                       dp->d_name + offset, best + best_offset) > 0)) {

   240                         if (best != NULL)

   241                             JLI_MemFree(best);

   242                         best = JLI_StringDup(dp->d_name);

   243                         best_offset = offset;

   244                     }

   245             }

   246         }

   247     } while (dp != NULL);

   248     (void) closedir(dirp);

   249     if (best == NULL)

   250         return (NULL);

   251     else {

   252         ret_str = JLI_MemAlloc(JLI_StrLen(dirname) + JLI_StrLen(best) + 2);

   253         sprintf(ret_str, "%s/%s", dirname, best);

   254         JLI_MemFree(best);

   255         return (ret_str);

   256     }

   257 }

   258 

   259 /*

   260  *      This is the global entry point. It examines the host for the optimal

   261  *      JRE to be used by scanning a set of directories.  The set of directories

   262  *      is platform dependent and can be overridden by the environment

   263  *      variable JAVA_VERSION_PATH.

   264  *

   265  *      This routine itself simply determines the set of appropriate

   266  *      directories before passing control onto ProcessDir().

   267  */

   268 char*

   269 LocateJRE(manifest_info* info)

   270 {

   271     char        *path;

   272     char        *home;

   273     char        *target = NULL;

   274     char        *dp;

   275     char        *cp;

   276 

   277     /*

   278      * Start by getting JAVA_VERSION_PATH

   279      */

   280     if (info->jre_restrict_search) {

   281         path = JLI_StringDup(system_dir);

   282     } else if ((path = getenv("JAVA_VERSION_PATH")) != NULL) {

   283         path = JLI_StringDup(path);

   284     } else {

   285         if ((home = getenv("HOME")) != NULL) {

   286             path = (char *)JLI_MemAlloc(JLI_StrLen(home) + \

   287                         JLI_StrLen(system_dir) + JLI_StrLen(user_dir) + 2);

   288             sprintf(path, "%s%s:%s", home, user_dir, system_dir);

   289         } else {

   290             path = JLI_StringDup(system_dir);

   291         }

   292     }

   293 

   294     /*

   295      * Step through each directory on the path. Terminate the scan with

   296      * the first directory with an acceptable JRE.

   297      */

   298     cp = dp = path;

   299     while (dp != NULL) {

   300         cp = JLI_StrChr(dp, (int)':');

   301         if (cp != NULL)

   302             *cp = '\0';

   303         if ((target = ProcessDir(info, dp)) != NULL)

   304             break;

   305         dp = cp;

   306         if (dp != NULL)

   307             dp++;

   308     }

   309     JLI_MemFree(path);

   310     return (target);

   311 }

   312 

   313 /*

   314  * Given a path to a jre to execute, this routine checks if this process

   315  * is indeed that jre.  If not, it exec's that jre.

   316  *

   317  * We want to actually check the paths rather than just the version string

   318  * built into the executable, so that given version specification (and

   319  * JAVA_VERSION_PATH) will yield the exact same Java environment, regardless

   320  * of the version of the arbitrary launcher we start with.

   321  */

   322 void

   323 ExecJRE(char *jre, char **argv)

   324 {

   325     char    wanted[PATH_MAX];

   326     const char* progname = GetProgramName();

   327     const char* execname = NULL;

   328 

   329     /*

   330      * Resolve the real path to the directory containing the selected JRE.

   331      */

   332     if (realpath(jre, wanted) == NULL) {

   333         JLI_ReportErrorMessage(JRE_ERROR9, jre);

   334         exit(1);

   335     }

   336 

   337     /*

   338      * Resolve the real path to the currently running launcher.

   339      */

   340     SetExecname(argv);

   341     execname = GetExecName();

   342     if (execname == NULL) {

   343         JLI_ReportErrorMessage(JRE_ERROR10);

   344         exit(1);

   345     }

   346 

   347     /*

   348      * If the path to the selected JRE directory is a match to the initial

   349      * portion of the path to the currently executing JRE, we have a winner!

   350      * If so, just return.

   351      */

   352     if (JLI_StrNCmp(wanted, execname, JLI_StrLen(wanted)) == 0)

   353         return;                 /* I am the droid you were looking for */

   354 

   355 

   356     /*

   357      * This should never happen (because of the selection code in SelectJRE),

   358      * but check for "impossibly" long path names just because buffer overruns

   359      * can be so deadly.

   360      */

   361     if (JLI_StrLen(wanted) + JLI_StrLen(progname) + 6 > PATH_MAX) {

   362         JLI_ReportErrorMessage(JRE_ERROR11);

   363         exit(1);

   364     }

   365 

   366     /*

   367      * Construct the path and exec it.

   368      */

   369     (void)JLI_StrCat(JLI_StrCat(wanted, "/bin/"), progname);

   370     argv[0] = JLI_StringDup(progname);

   371     if (JLI_IsTraceLauncher()) {

   372         int i;

   373         printf("ReExec Command: %s (%s)\n", wanted, argv[0]);

   374         printf("ReExec Args:");

   375         for (i = 1; argv[i] != NULL; i++)

   376             printf(" %s", argv[i]);

   377         printf("\n");

   378     }

   379     JLI_TraceLauncher("TRACER_MARKER:About to EXEC\n");

   380     (void)fflush(stdout);

   381     (void)fflush(stderr);

   382     execv(wanted, argv);

   383     JLI_ReportErrorMessageSys(JRE_ERROR12, wanted);

   384     exit(1);

   385 }

   386 

   387 /*

   388  * "Borrowed" from Solaris 10 where the unsetenv() function is being added

   389  * to libc thanks to SUSv3 (Standard Unix Specification, version 3). As

   390  * such, in the fullness of time this will appear in libc on all relevant

   391  * Solaris/Linux platforms and maybe even the Windows platform.  At that

   392  * time, this stub can be removed.

   393  *

   394  * This implementation removes the environment locking for multithreaded

   395  * applications.  (We don't have access to these mutexes within libc and

   396  * the launcher isn't multithreaded.)  Note that what remains is platform

   397  * independent, because it only relies on attributes that a POSIX environment

   398  * defines.

   399  *

   400  * Returns 0 on success, -1 on failure.

   401  *

   402  * Also removed was the setting of errno.  The only value of errno set

   403  * was EINVAL ("Invalid Argument").

   404  */

   405 

   406 /*

   407  * s1(environ) is name=value

   408  * s2(name) is name(not the form of name=value).

   409  * if names match, return value of 1, else return 0

   410  */

   411 static int

   412 match_noeq(const char *s1, const char *s2)

   413 {

   414         while (*s1 == *s2++) {

   415                 if (*s1++ == '=')

   416                         return (1);

   417         }

   418         if (*s1 == '=' && s2[-1] == '\0')

   419                 return (1);

   420         return (0);

   421 }

   422 

   423 /*

   424  * added for SUSv3 standard

   425  *

   426  * Delete entry from environ.

   427  * Do not free() memory!  Other threads may be using it.

   428  * Keep it around forever.

   429  */

   430 static int

   431 borrowed_unsetenv(const char *name)

   432 {

   433         long    idx;            /* index into environ */

   434 

   435         if (name == NULL || *name == '\0' ||

   436             JLI_StrChr(name, '=') != NULL) {

   437                 return (-1);

   438         }

   439 

   440         for (idx = 0; environ[idx] != NULL; idx++) {

   441                 if (match_noeq(environ[idx], name))

   442                         break;

   443         }

   444         if (environ[idx] == NULL) {

   445                 /* name not found but still a success */

   446                 return (0);

   447         }

   448         /* squeeze up one entry */

   449         do {

   450                 environ[idx] = environ[idx+1];

   451         } while (environ[++idx] != NULL);

   452 

   453         return (0);

   454 }

   455 /* --- End of "borrowed" code --- */

   456 

   457 /*

   458  * Wrapper for unsetenv() function.

   459  */

   460 int

   461 UnsetEnv(char *name)

   462 {

   463     return(borrowed_unsetenv(name));

   464 }

   465 

   466 const char *

   467 jlong_format_specifier() {

   468     return "%lld";

   469 }

   470 

   471 jboolean

   472 IsJavaw()

   473 {

   474     /* noop on UNIX */

   475     return JNI_FALSE;

   476 }

   477 

   478 void

   479 InitLauncher(jboolean javaw)

   480 {

   481     JLI_SetTraceLauncher();

   482 }

   483 

   484 /*

   485  * The implementation for finding classes from the bootstrap

   486  * class loader, refer to java.h

   487  */

   488 static FindClassFromBootLoader_t *findBootClass = NULL;

   489 

   490 jclass

   491 FindBootStrapClass(JNIEnv *env, const char* classname)

   492 {

   493    if (findBootClass == NULL) {

   494        findBootClass = (FindClassFromBootLoader_t *)dlsym(RTLD_DEFAULT,

   495           "JVM_FindClassFromBootLoader");

   496        if (findBootClass == NULL) {

   497            JLI_ReportErrorMessage(DLL_ERROR4,

   498                "JVM_FindClassFromBootLoader");

   499            return NULL;

   500        }

   501    }

   502    return findBootClass(env, classname);

   503 }

   504