/*
* Determine if there is an acceptable JRE in the registry directory top_key.
* Upon locating the "best" one, return a fully qualified path to it.
* "Best" is defined as the most advanced JRE meeting the constraints
* contained in the manifest_info. If no JRE in this directory meets the
* constraints, return NULL.
*
* It doesn't matter if we get an error reading the registry, or we just
* don't find anything interesting in the directory. We just return NULL
* in either case.
*/
static char *
ProcessDir(manifest_info* info, HKEY top_key) {
DWORD index = 0;
HKEY ver_key;
char name[MAXNAMELEN];
int len;
char *best = NULL;
/*
* Enumerate "<top_key>/SOFTWARE/JavaSoft/Java Runtime Environment"
* searching for the best available version.
*/
while (RegEnumKey(top_key, index, name, MAXNAMELEN) == ERROR_SUCCESS) {
index++;
if (acceptable_release(name, info->jre_version))
if ((best == NULL) || (exact_version_id(name, best) > 0)) {
if (best != NULL)
free(best);
best = strdup(name);
}
}
/*
* Extract "JavaHome" from the "best" registry directory and return
* that path. If no appropriate version was located, or there is an
* error in extracting the "JavaHome" string, return null.
*/
if (best == NULL)
return (NULL);
else {
if (RegOpenKeyEx(top_key, best, 0, KEY_READ, &ver_key)
!= ERROR_SUCCESS) {
free(best);
if (ver_key != NULL)
RegCloseKey(ver_key);
return (NULL);
}
free(best);
len = MAXNAMELEN;
if (RegQueryValueEx(ver_key, "JavaHome", NULL, NULL, (LPBYTE)name, &len)
!= ERROR_SUCCESS) {
if (ver_key != NULL)
RegCloseKey(ver_key);
return (NULL);
}
if (ver_key != NULL)
RegCloseKey(ver_key);
return (strdup(name));
}
}
/*
* The SelectVersion() routine ensures that an appropriate version of
* the JRE is running. The specification for the appropriate version
* is obtained from either the manifest of a jar file (preferred) or
* from command line options.
*/
static void
SelectVersion(int argc, char **argv, char **main_class)
{
char *arg;
char **new_argv;
char **new_argp;
char *operand;
char *version = NULL;
char *jre = NULL;
int jarflag = 0;
int restrict_search = -1; /* -1 implies not known */
manifest_info info;
char env_entry[MAXNAMELEN + 24] = ENV_ENTRY "=";
char *env_in;
int res;
/*
* If the version has already been selected, set *main_class
* with the value passed through the environment (if any) and
* simply return.
*/
if ((env_in = getenv(ENV_ENTRY)) != NULL) {
if (*env_in != '\0')
*main_class = strdup(env_in);
return;
}
/*
* Scan through the arguments for options relevant to multiple JRE
* support. For reference, the command line syntax is defined as:
*
* SYNOPSIS
* java [options] class [argument...]
*
* java [options] -jar file.jar [argument...]
*
* As the scan is performed, make a copy of the argument list with
* the version specification options (new to 1.5) removed, so that
* a version less than 1.5 can be exec'd.
*/
new_argv = MemAlloc((argc + 1) * sizeof(char*));
new_argv[0] = argv[0];
new_argp = &new_argv[1];
argc--;
argv++;
while ((arg = *argv) != 0 && *arg == '-') {
if (strncmp(arg, "-version:", 9) == 0) {
version = arg + 9;
} else if (strcmp(arg, "-jre-restrict-search") == 0) {
restrict_search = 1;
} else if (strcmp(arg, "-no-jre-restrict-search") == 0) {
restrict_search = 0;
} else {
if (strcmp(arg, "-jar") == 0)
jarflag = 1;
/* deal with "unfortunate" classpath syntax */
if (strcmp(arg, "-classpath") == 0 || strcmp(arg, "-cp") == 0) {
if (argc >= 1) {
*new_argp++ = arg;
argc--;
argv++;
arg = *argv;
}
}
*new_argp++ = arg;
}
argc--;
argv++;
}
if (argc <= 0) { /* No operand? Possibly legit with -[full]version */
operand = NULL;
} else {
argc--;
*new_argp++ = operand = *argv++;
}
while (argc-- > 0) /* Copy over [argument...] */
*new_argp++ = *argv++;
*new_argp = NULL;
/*
* If there is a jar file, read the manifest. If the jarfile can't be
* read, the manifest can't be read from the jar file, or the manifest
* is corrupt, issue the appropriate error messages and exit.
*
* Even if there isn't a jar file, construct a manifest_info structure
* containing the command line information. Its a convenient way to carry
* this data around.
*/
if (jarflag && operand) {
if ((res = parse_manifest(operand, &info)) != 0) {
if (res == -1)
ReportErrorMessage2("Unable to access jarfile %s",
operand, JNI_TRUE);
else
ReportErrorMessage2("Invalid or corrupt jarfile %s",
operand, JNI_TRUE);
exit(1);
}
} else {
info.manifest_version = NULL;
info.main_class = NULL;
info.jre_version = NULL;
info.jre_restrict_search = 0;
}
/*
* The JRE-Version and JRE-Restrict-Search values (if any) from the
* manifest are overwritten by any specified on the command line.
*/
if (version != NULL)
info.jre_version = version;
if (restrict_search != -1)
info.jre_restrict_search = restrict_search;
/*
* "Valid" returns (other than unrecoverable errors) follow. Set
* main_class as a side-effect of this routine.
*/
if (info.main_class != NULL)
*main_class = strdup(info.main_class);
/*
* If no version selection information is found either on the command
* line or in the manifest, simply return.
*/
if (info.jre_version == NULL) {
free_manifest();
free(new_argv);
return;
}
/*
* Check for correct syntax of the version specification (JSR 56).
*/
if (!valid_version_string(info.jre_version)) {
ReportErrorMessage2("Syntax error in version specification \"%s\"",
info.jre_version, JNI_TRUE);
exit(1);
}
/*
* Find the appropriate JVM on the system. Just to be as forgiving as
* possible, if the standard algorithms don't locate an appropriate
* jre, check to see if the one running will satisfy the requirements.
* This can happen on systems which haven't been set-up for multiple
* JRE support.
*/
jre = LocateJRE(&info);
if (_launcher_debug)
printf("JRE-Version = %s, JRE-Restrict-Search = %s Selected = %s\n",
(info.jre_version?info.jre_version:"null"),
(info.jre_restrict_search?"true":"false"), (jre?jre:"null"));
if (jre == NULL) {
if (acceptable_release(FULL_VERSION, info.jre_version)) {
free_manifest();
free(new_argv);
return;
} else {
ReportErrorMessage2(
"Unable to locate JRE meeting specification \"%s\"",
info.jre_version, JNI_TRUE);
exit(1);
}
}
/*
* If I'm not the chosen one, exec the chosen one. Returning from
* ExecJRE indicates that I am indeed the chosen one.
*
* The private environment variable _JAVA_VERSION_SET is used to
* prevent the chosen one from re-reading the manifest file and
* using the values found within to override the (potential) command
* line flags stripped from argv (because the target may not
* understand them). Passing the MainClass value is an optimization
* to avoid locating, expanding and parsing the manifest extra
* times.
*/
if (info.main_class != NULL) {
if (strlen(info.main_class) <= MAXNAMELEN) {
(void)strcat(env_entry, info.main_class);
} else {
ReportErrorMessage("Error: main-class: attribute exceeds system limits\n", JNI_TRUE);
exit(1);
}
}
(void)putenv(env_entry);
ExecJRE(jre, new_argv);
free_manifest();
free(new_argv);
return;
}
