src/solaris/native/java/lang/UNIXProcess_md.c
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*** 45,67 ****
#else
#include <wait.h>
#endif
#include <signal.h>
#include <string.h>
- #include <errno.h>
- #include <dirent.h>
- #include <unistd.h>
- #include <fcntl.h>
- #include <limits.h>
! #ifdef __APPLE__
! #include <crt_externs.h>
! #define environ (*_NSGetEnviron())
#endif
/*
! * There are 3 possible strategies we might use to "fork":
*
* - fork(2). Very portable and reliable but subject to
* failure due to overcommit (see the documentation on
* /proc/sys/vm/overcommit_memory in Linux proc(5)).
* This is the ancient problem of spurious failure whenever a large
--- 45,63 ----
#else
#include <wait.h>
#endif
#include <signal.h>
#include <string.h>
! #if defined(__solaris__) || defined(_ALLBSD_SOURCE)
! #include <spawn.h>
#endif
+ #include "childproc.h"
+
/*
! * There are 4 possible strategies we might use to "fork":
*
* - fork(2). Very portable and reliable but subject to
* failure due to overcommit (see the documentation on
* /proc/sys/vm/overcommit_memory in Linux proc(5)).
* This is the ancient problem of spurious failure whenever a large
*** 92,177 ****
* # Error: pthread_getattr_np failed with errno = 3 (ESRCH)
* We believe this is a glibc bug, reported here:
* http://sources.redhat.com/bugzilla/show_bug.cgi?id=10311
* but the glibc maintainers closed it as WONTFIX.
*
* Based on the above analysis, we are currently using vfork() on
! * Linux and fork() on other Unix systems, but the code to use clone()
! * remains.
*/
- #define START_CHILD_USE_CLONE 0 /* clone() currently disabled; see above. */
- #ifndef START_CHILD_USE_CLONE
- #ifdef __linux__
- #define START_CHILD_USE_CLONE 1
- #else
- #define START_CHILD_USE_CLONE 0
- #endif
- #endif
-
- /* By default, use vfork() on Linux. */
- #ifndef START_CHILD_USE_VFORK
- #ifdef __linux__
- #define START_CHILD_USE_VFORK 1
- #else
- #define START_CHILD_USE_VFORK 0
- #endif
- #endif
-
- #if START_CHILD_USE_CLONE
- #include <sched.h>
- #define START_CHILD_SYSTEM_CALL "clone"
- #elif START_CHILD_USE_VFORK
- #define START_CHILD_SYSTEM_CALL "vfork"
- #else
- #define START_CHILD_SYSTEM_CALL "fork"
- #endif
-
- #ifndef STDIN_FILENO
- #define STDIN_FILENO 0
- #endif
-
- #ifndef STDOUT_FILENO
- #define STDOUT_FILENO 1
- #endif
-
- #ifndef STDERR_FILENO
- #define STDERR_FILENO 2
- #endif
-
- #ifndef SA_NOCLDSTOP
- #define SA_NOCLDSTOP 0
- #endif
-
- #ifndef SA_RESTART
- #define SA_RESTART 0
- #endif
-
- #define FAIL_FILENO (STDERR_FILENO + 1)
-
- /* TODO: Refactor. */
- #define RESTARTABLE(_cmd, _result) do { \
- do { \
- _result = _cmd; \
- } while((_result == -1) && (errno == EINTR)); \
- } while(0)
-
- /* This is one of the rare times it's more portable to declare an
- * external symbol explicitly, rather than via a system header.
- * The declaration is standardized as part of UNIX98, but there is
- * no standard (not even de-facto) header file where the
- * declaration is to be found. See:
- * http://www.opengroup.org/onlinepubs/009695399/functions/environ.html
- * http://www.opengroup.org/onlinepubs/009695399/functions/xsh_chap02_02.html
- *
- * "All identifiers in this volume of IEEE Std 1003.1-2001, except
- * environ, are defined in at least one of the headers" (!)
- */
- extern char **environ;
-
-
static void
setSIGCHLDHandler(JNIEnv *env)
{
/* There is a subtle difference between having the signal handler
* for SIGCHLD be SIG_DFL and SIG_IGN. We cannot obtain process
--- 88,113 ----
* # Error: pthread_getattr_np failed with errno = 3 (ESRCH)
* We believe this is a glibc bug, reported here:
* http://sources.redhat.com/bugzilla/show_bug.cgi?id=10311
* but the glibc maintainers closed it as WONTFIX.
*
+ * - posix_spawn(). While posix_spawn() is a fairly elaborate and
+ * complicated system call, it can't quite do everything that the old
+ * fork()/exec() combination can do, so the only feasible way to do
+ * this, is to use posix_spawn to launch a new helper executable
+ * "jprochelper", which in turn execs the target (after cleaning
+ * up file-descriptors etc.) The end result is the same as before,
+ * a child process linked to the parent in the same way, but it
+ * avoids the problem of duplicating the parent (VM) process
+ * address space temporarily, before launching the target command.
+ *
* Based on the above analysis, we are currently using vfork() on
! * Linux, posix_spawn() on Mac and fork() on Solaris, but the code to
! * use clone() and fork() remains.
*/
static void
setSIGCHLDHandler(JNIEnv *env)
{
/* There is a subtle difference between having the signal handler
* for SIGCHLD be SIG_DFL and SIG_IGN. We cannot obtain process
*** 243,299 ****
count += (*s == c);
return count;
}
static const char * const *
! splitPath(JNIEnv *env, const char *path)
{
! const char *p, *q;
! char **pathv;
int i;
int count = countOccurrences(path, ':') + 1;
! pathv = NEW(char*, count+1);
! pathv[count] = NULL;
! for (p = path, i = 0; i < count; i++, p = q + 1) {
! for (q = p; (*q != ':') && (*q != '\0'); q++)
! ;
! if (q == p) /* empty PATH component => "." */
! pathv[i] = "./";
! else {
! int addSlash = ((*(q - 1)) != '/');
! pathv[i] = NEW(char, q - p + addSlash + 1);
! memcpy(pathv[i], p, q - p);
! if (addSlash)
! pathv[i][q - p] = '/';
! pathv[i][q - p + addSlash] = '\0';
}
! }
! return (const char * const *) pathv;
}
- /**
- * Cached value of JVM's effective PATH.
- * (We don't support putenv("PATH=...") in native code)
- */
- static const char *parentPath;
-
- /**
- * Split, canonicalized version of parentPath
- */
- static const char * const *parentPathv;
-
- static jfieldID field_exitcode;
-
JNIEXPORT void JNICALL
! Java_java_lang_UNIXProcess_initIDs(JNIEnv *env, jclass clazz)
{
! field_exitcode = (*env)->GetFieldID(env, clazz, "exitcode", "I");
!
! parentPath = effectivePath();
! parentPathv = splitPath(env, parentPath);
!
setSIGCHLDHandler(env);
}
#ifndef WIFEXITED
--- 179,217 ----
count += (*s == c);
return count;
}
static const char * const *
! effectivePathv(JNIEnv *env)
{
! char *p;
int i;
+ const char *path = effectivePath();
int count = countOccurrences(path, ':') + 1;
+ size_t pathvsize = sizeof(const char *) * (count+1);
+ size_t pathsize = strlen(path) + 1;
+ const char **pathv = (const char **) xmalloc(env, pathvsize + pathsize);
! if (pathv == NULL)
! return NULL;
! p = (char *) pathv + pathvsize;
! memcpy(p, path, pathsize);
! /* split PATH by replacing ':' with NULs; empty components => "." */
! for (i = 0; i < count; i++) {
! char *q = p + strcspn(p, ":");
! pathv[i] = (p == q) ? "." : p;
! *q = '\0';
! p = q + 1;
}
! pathv[count] = NULL;
! return pathv;
}
JNIEXPORT void JNICALL
! Java_java_lang_UNIXProcess_init(JNIEnv *env, jclass clazz)
{
! parentPathv = effectivePathv(env);
setSIGCHLDHandler(env);
}
#ifndef WIFEXITED
*** 356,455 ****
*/
return status;
}
}
- static ssize_t
- restartableWrite(int fd, const void *buf, size_t count)
- {
- ssize_t result;
- RESTARTABLE(write(fd, buf, count), result);
- return result;
- }
-
- static int
- restartableDup2(int fd_from, int fd_to)
- {
- int err;
- RESTARTABLE(dup2(fd_from, fd_to), err);
- return err;
- }
-
- static int
- restartableClose(int fd)
- {
- int err;
- RESTARTABLE(close(fd), err);
- return err;
- }
-
- static int
- closeSafely(int fd)
- {
- return (fd == -1) ? 0 : restartableClose(fd);
- }
-
- static int
- isAsciiDigit(char c)
- {
- return c >= '0' && c <= '9';
- }
-
- #ifdef _ALLBSD_SOURCE
- #define FD_DIR "/dev/fd"
- #define dirent64 dirent
- #define readdir64 readdir
- #else
- #define FD_DIR "/proc/self/fd"
- #endif
-
- static int
- closeDescriptors(void)
- {
- DIR *dp;
- struct dirent64 *dirp;
- int from_fd = FAIL_FILENO + 1;
-
- /* We're trying to close all file descriptors, but opendir() might
- * itself be implemented using a file descriptor, and we certainly
- * don't want to close that while it's in use. We assume that if
- * opendir() is implemented using a file descriptor, then it uses
- * the lowest numbered file descriptor, just like open(). So we
- * close a couple explicitly. */
-
- restartableClose(from_fd); /* for possible use by opendir() */
- restartableClose(from_fd + 1); /* another one for good luck */
-
- if ((dp = opendir(FD_DIR)) == NULL)
- return 0;
-
- /* We use readdir64 instead of readdir to work around Solaris bug
- * 6395699: /proc/self/fd fails to report file descriptors >= 1024 on Solaris 9
- */
- while ((dirp = readdir64(dp)) != NULL) {
- int fd;
- if (isAsciiDigit(dirp->d_name[0]) &&
- (fd = strtol(dirp->d_name, NULL, 10)) >= from_fd + 2)
- restartableClose(fd);
- }
-
- closedir(dp);
-
- return 1;
- }
-
- static int
- moveDescriptor(int fd_from, int fd_to)
- {
- if (fd_from != fd_to) {
- if ((restartableDup2(fd_from, fd_to) == -1) ||
- (restartableClose(fd_from) == -1))
- return -1;
- }
- return 0;
- }
-
static const char *
getBytes(JNIEnv *env, jbyteArray arr)
{
return arr == NULL ? NULL :
(const char*) (*env)->GetByteArrayElements(env, arr, NULL);
--- 274,283 ----
*** 461,483 ****
if (parr != NULL)
(*env)->ReleaseByteArrayElements(env, arr, (jbyte*) parr, JNI_ABORT);
}
static void
- initVectorFromBlock(const char**vector, const char* block, int count)
- {
- int i;
- const char *p;
- for (i = 0, p = block; i < count; i++) {
- /* Invariant: p always points to the start of a C string. */
- vector[i] = p;
- while (*(p++));
- }
- vector[count] = NULL;
- }
-
- static void
throwIOException(JNIEnv *env, int errnum, const char *defaultDetail)
{
static const char * const format = "error=%d, %s";
const char *detail = defaultDetail;
char *errmsg;
--- 289,298 ----
*** 488,497 ****
--- 303,315 ----
if (strcmp(s, "Unknown error") != 0)
detail = s;
}
/* ASCII Decimal representation uses 2.4 times as many bits as binary. */
errmsg = NEW(char, strlen(format) + strlen(detail) + 3 * sizeof(errnum));
+ if (errmsg == NULL)
+ return;
+
sprintf(errmsg, format, errnum, detail);
s = JNU_NewStringPlatform(env, errmsg);
if (s != NULL) {
jobject x = JNU_NewObjectByName(env, "java/io/IOException",
"(Ljava/lang/String;)V", s);
*** 513,794 ****
va_end(ap);
fclose(tty);
}
#endif /* DEBUG_PROCESS */
- /**
- * Exec FILE as a traditional Bourne shell script (i.e. one without #!).
- * If we could do it over again, we would probably not support such an ancient
- * misfeature, but compatibility wins over sanity. The original support for
- * this was imported accidentally from execvp().
- */
static void
! execve_as_traditional_shell_script(const char *file,
! const char *argv[],
! const char *const envp[])
{
! /* Use the extra word of space provided for us in argv by caller. */
! const char *argv0 = argv[0];
! const char *const *end = argv;
! while (*end != NULL)
! ++end;
! memmove(argv+2, argv+1, (end-argv) * sizeof (*end));
! argv[0] = "/bin/sh";
! argv[1] = file;
! execve(argv[0], (char **) argv, (char **) envp);
! /* Can't even exec /bin/sh? Big trouble, but let's soldier on... */
! memmove(argv+1, argv+2, (end-argv) * sizeof (*end));
! argv[0] = argv0;
}
! /**
! * Like execve(2), except that in case of ENOEXEC, FILE is assumed to
! * be a shell script and the system default shell is invoked to run it.
! */
! static void
! execve_with_shell_fallback(const char *file,
! const char *argv[],
! const char *const envp[])
! {
! #if START_CHILD_USE_CLONE || START_CHILD_USE_VFORK
! /* shared address space; be very careful. */
! execve(file, (char **) argv, (char **) envp);
! if (errno == ENOEXEC)
! execve_as_traditional_shell_script(file, argv, envp);
! #else
! /* unshared address space; we can mutate environ. */
! environ = (char **) envp;
! execvp(file, (char **) argv);
! #endif
! }
!
! /**
! * 'execvpe' should have been included in the Unix standards,
! * and is a GNU extension in glibc 2.10.
*
! * JDK_execvpe is identical to execvp, except that the child environment is
! * specified via the 3rd argument instead of being inherited from environ.
*/
! static void
! JDK_execvpe(const char *file,
! const char *argv[],
! const char *const envp[])
{
! if (envp == NULL || (char **) envp == environ) {
! execvp(file, (char **) argv);
return;
}
!
! if (*file == '\0') {
! errno = ENOENT;
! return;
}
!
! if (strchr(file, '/') != NULL) {
! execve_with_shell_fallback(file, argv, envp);
! } else {
! /* We must search PATH (parent's, not child's) */
! char expanded_file[PATH_MAX];
! int filelen = strlen(file);
! int sticky_errno = 0;
! const char * const * dirs;
! for (dirs = parentPathv; *dirs; dirs++) {
! const char * dir = *dirs;
! int dirlen = strlen(dir);
! if (filelen + dirlen + 1 >= PATH_MAX) {
! errno = ENAMETOOLONG;
! continue;
! }
! memcpy(expanded_file, dir, dirlen);
! memcpy(expanded_file + dirlen, file, filelen);
! expanded_file[dirlen + filelen] = '\0';
! execve_with_shell_fallback(expanded_file, argv, envp);
! /* There are 3 responses to various classes of errno:
! * return immediately, continue (especially for ENOENT),
! * or continue with "sticky" errno.
! *
! * From exec(3):
! *
! * If permission is denied for a file (the attempted
! * execve returned EACCES), these functions will continue
! * searching the rest of the search path. If no other
! * file is found, however, they will return with the
! * global variable errno set to EACCES.
! */
! switch (errno) {
! case EACCES:
! sticky_errno = errno;
! /* FALLTHRU */
! case ENOENT:
! case ENOTDIR:
! #ifdef ELOOP
! case ELOOP:
! #endif
! #ifdef ESTALE
! case ESTALE:
! #endif
! #ifdef ENODEV
! case ENODEV:
! #endif
! #ifdef ETIMEDOUT
! case ETIMEDOUT:
! #endif
! break; /* Try other directories in PATH */
! default:
! return;
! }
! }
! if (sticky_errno != 0)
! errno = sticky_errno;
! }
}
! /*
! * Reads nbyte bytes from file descriptor fd into buf,
! * The read operation is retried in case of EINTR or partial reads.
! *
! * Returns number of bytes read (normally nbyte, but may be less in
! * case of EOF). In case of read errors, returns -1 and sets errno.
*/
! static ssize_t
! readFully(int fd, void *buf, size_t nbyte)
! {
! ssize_t remaining = nbyte;
! for (;;) {
! ssize_t n = read(fd, buf, remaining);
! if (n == 0) {
! return nbyte - remaining;
! } else if (n > 0) {
! remaining -= n;
! if (remaining <= 0)
! return nbyte;
! /* We were interrupted in the middle of reading the bytes.
! * Unlikely, but possible. */
! buf = (void *) (((char *)buf) + n);
! } else if (errno == EINTR) {
! /* Strange signals like SIGJVM1 are possible at any time.
! * See http://www.dreamsongs.com/WorseIsBetter.html */
! } else {
! return -1;
! }
! }
! }
! typedef struct _ChildStuff
! {
! int in[2];
! int out[2];
! int err[2];
! int fail[2];
! int fds[3];
! const char **argv;
! const char **envv;
! const char *pdir;
! jboolean redirectErrorStream;
! #if START_CHILD_USE_CLONE
! void *clone_stack;
! #endif
! } ChildStuff;
!
! static void
! copyPipe(int from[2], int to[2])
! {
! to[0] = from[0];
! to[1] = from[1];
! }
!
! /**
! * Child process after a successful fork() or clone().
! * This function must not return, and must be prepared for either all
! * of its address space to be shared with its parent, or to be a copy.
! * It must not modify global variables such as "environ".
! */
! static int
! childProcess(void *arg)
! {
! const ChildStuff* p = (const ChildStuff*) arg;
!
! /* Close the parent sides of the pipes.
! Closing pipe fds here is redundant, since closeDescriptors()
! would do it anyways, but a little paranoia is a good thing. */
! if ((closeSafely(p->in[1]) == -1) ||
! (closeSafely(p->out[0]) == -1) ||
! (closeSafely(p->err[0]) == -1) ||
! (closeSafely(p->fail[0]) == -1))
! goto WhyCantJohnnyExec;
!
! /* Give the child sides of the pipes the right fileno's. */
! /* Note: it is possible for in[0] == 0 */
! if ((moveDescriptor(p->in[0] != -1 ? p->in[0] : p->fds[0],
! STDIN_FILENO) == -1) ||
! (moveDescriptor(p->out[1]!= -1 ? p->out[1] : p->fds[1],
! STDOUT_FILENO) == -1))
! goto WhyCantJohnnyExec;
!
! if (p->redirectErrorStream) {
! if ((closeSafely(p->err[1]) == -1) ||
! (restartableDup2(STDOUT_FILENO, STDERR_FILENO) == -1))
! goto WhyCantJohnnyExec;
! } else {
! if (moveDescriptor(p->err[1] != -1 ? p->err[1] : p->fds[2],
! STDERR_FILENO) == -1)
! goto WhyCantJohnnyExec;
}
!
! if (moveDescriptor(p->fail[1], FAIL_FILENO) == -1)
! goto WhyCantJohnnyExec;
!
! /* close everything */
! if (closeDescriptors() == 0) { /* failed, close the old way */
! int max_fd = (int)sysconf(_SC_OPEN_MAX);
! int fd;
! for (fd = FAIL_FILENO + 1; fd < max_fd; fd++)
! if (restartableClose(fd) == -1 && errno != EBADF)
! goto WhyCantJohnnyExec;
}
!
! /* change to the new working directory */
! if (p->pdir != NULL && chdir(p->pdir) < 0)
! goto WhyCantJohnnyExec;
!
! if (fcntl(FAIL_FILENO, F_SETFD, FD_CLOEXEC) == -1)
! goto WhyCantJohnnyExec;
!
! JDK_execvpe(p->argv[0], p->argv, p->envv);
!
! WhyCantJohnnyExec:
! /* We used to go to an awful lot of trouble to predict whether the
! * child would fail, but there is no reliable way to predict the
! * success of an operation without *trying* it, and there's no way
! * to try a chdir or exec in the parent. Instead, all we need is a
! * way to communicate any failure back to the parent. Easy; we just
! * send the errno back to the parent over a pipe in case of failure.
! * The tricky thing is, how do we communicate the *success* of exec?
! * We use FD_CLOEXEC together with the fact that a read() on a pipe
! * yields EOF when the write ends (we have two of them!) are closed.
! */
! {
! int errnum = errno;
! restartableWrite(FAIL_FILENO, &errnum, sizeof(errnum));
! }
! restartableClose(FAIL_FILENO);
! _exit(-1);
! return 0; /* Suppress warning "no return value from function" */
}
/**
- * Start a child process running function childProcess.
- * This function only returns in the parent.
* We are unusually paranoid; use of clone/vfork is
* especially likely to tickle gcc/glibc bugs.
*/
#ifdef __attribute_noinline__ /* See: sys/cdefs.h */
__attribute_noinline__
#endif
static pid_t
! startChild(ChildStuff *c) {
! #if START_CHILD_USE_CLONE
#define START_CHILD_CLONE_STACK_SIZE (64 * 1024)
/*
* See clone(2).
* Instead of worrying about which direction the stack grows, just
* allocate twice as much and start the stack in the middle.
--- 331,408 ----
va_end(ap);
fclose(tty);
}
#endif /* DEBUG_PROCESS */
static void
! copyPipe(int from[2], int to[2])
{
! to[0] = from[0];
! to[1] = from[1];
}
! /* arg is an array of pointers to 0 terminated strings. array is terminated
! * by a null element.
*
! * *nelems and *nbytes receive the number of elements of array (incl 0)
! * and total number of bytes (incl. 0)
! * Note. An empty array will have one null element
! * But if arg is null, then *nelems set to 0, and *nbytes to 0
*/
! static void arraysize(const char * const *arg, int *nelems, int *nbytes)
{
! int i, bytes, count;
! const char * const *a = arg;
! char *p;
! int *q;
! if (arg == 0) {
! *nelems = 0;
! *nbytes = 0;
return;
}
! /* count the array elements and number of bytes */
! for (count=0, bytes=0; *a != 0; count++, a++) {
! bytes += strlen(*a)+1;
}
! *nbytes = bytes;
! *nelems = count+1;
}
! /* copy the strings from arg[] into buf, starting at given offset
! * return new offset to next free byte
*/
! static int copystrings(char *buf, int offset, const char * const *arg) {
! char *p;
! const char * const *a;
! int count=0;
! if (arg == 0) {
! return offset;
}
! for (p=buf+offset, a=arg; *a != 0; a++) {
! int len = strlen(*a) +1;
! memcpy(p, *a, len);
! p += len;
! count += len;
}
! return offset+count;
}
/**
* We are unusually paranoid; use of clone/vfork is
* especially likely to tickle gcc/glibc bugs.
*/
#ifdef __attribute_noinline__ /* See: sys/cdefs.h */
__attribute_noinline__
#endif
+
+ #define START_CHILD_USE_CLONE 0 /* clone() currently disabled; see above. */
+
+ #ifdef START_CHILD_USE_CLONE
static pid_t
! cloneChild(ChildStuff *c) {
! #ifdef __linux__
#define START_CHILD_CLONE_STACK_SIZE (64 * 1024)
/*
* See clone(2).
* Instead of worrying about which direction the stack grows, just
* allocate twice as much and start the stack in the middle.
*** 798,869 ****
return -1;
return clone(childProcess,
c->clone_stack + START_CHILD_CLONE_STACK_SIZE,
CLONE_VFORK | CLONE_VM | SIGCHLD, c);
#else
! #if START_CHILD_USE_VFORK
/*
* We separate the call to vfork into a separate function to make
* very sure to keep stack of child from corrupting stack of parent,
* as suggested by the scary gcc warning:
* warning: variable 'foo' might be clobbered by 'longjmp' or 'vfork'
*/
! volatile pid_t resultPid = vfork();
! #else
/*
* From Solaris fork(2): In Solaris 10, a call to fork() is
* identical to a call to fork1(); only the calling thread is
* replicated in the child process. This is the POSIX-specified
* behavior for fork().
*/
! pid_t resultPid = fork();
! #endif
! if (resultPid == 0)
childProcess(c);
assert(resultPid != 0); /* childProcess never returns */
return resultPid;
- #endif /* ! START_CHILD_USE_CLONE */
}
JNIEXPORT jint JNICALL
Java_java_lang_UNIXProcess_forkAndExec(JNIEnv *env,
jobject process,
jbyteArray prog,
jbyteArray argBlock, jint argc,
jbyteArray envBlock, jint envc,
jbyteArray dir,
jintArray std_fds,
jboolean redirectErrorStream)
{
int errnum;
int resultPid = -1;
! int in[2], out[2], err[2], fail[2];
jint *fds = NULL;
const char *pprog = NULL;
const char *pargBlock = NULL;
const char *penvBlock = NULL;
ChildStuff *c;
in[0] = in[1] = out[0] = out[1] = err[0] = err[1] = fail[0] = fail[1] = -1;
if ((c = NEW(ChildStuff, 1)) == NULL) return -1;
c->argv = NULL;
c->envv = NULL;
c->pdir = NULL;
- #if START_CHILD_USE_CLONE
c->clone_stack = NULL;
- #endif
/* Convert prog + argBlock into a char ** argv.
* Add one word room for expansion of argv for use by
* execve_as_traditional_shell_script.
*/
assert(prog != NULL && argBlock != NULL);
if ((pprog = getBytes(env, prog)) == NULL) goto Catch;
if ((pargBlock = getBytes(env, argBlock)) == NULL) goto Catch;
if ((c->argv = NEW(const char *, argc + 3)) == NULL) goto Catch;
c->argv[0] = pprog;
initVectorFromBlock(c->argv+1, pargBlock, argc);
if (envBlock != NULL) {
/* Convert envBlock into a char ** envv */
if ((penvBlock = getBytes(env, envBlock)) == NULL) goto Catch;
--- 412,614 ----
return -1;
return clone(childProcess,
c->clone_stack + START_CHILD_CLONE_STACK_SIZE,
CLONE_VFORK | CLONE_VM | SIGCHLD, c);
#else
! /* not available on Solaris / Mac */
! assert(0);
! return -1;
! #endif
! }
! #endif
!
! static pid_t
! vforkChild(ChildStuff *c) {
! volatile pid_t resultPid;
!
/*
* We separate the call to vfork into a separate function to make
* very sure to keep stack of child from corrupting stack of parent,
* as suggested by the scary gcc warning:
* warning: variable 'foo' might be clobbered by 'longjmp' or 'vfork'
*/
! resultPid = vfork();
!
! if (resultPid == 0) {
! childProcess(c);
! }
! assert(resultPid != 0); /* childProcess never returns */
! return resultPid;
! }
!
! static pid_t
! forkChild(ChildStuff *c) {
! pid_t resultPid;
!
/*
* From Solaris fork(2): In Solaris 10, a call to fork() is
* identical to a call to fork1(); only the calling thread is
* replicated in the child process. This is the POSIX-specified
* behavior for fork().
*/
! resultPid = fork();
!
! if (resultPid == 0) {
childProcess(c);
+ }
assert(resultPid != 0); /* childProcess never returns */
return resultPid;
}
+ #if defined(__solaris__) || defined(_ALLBSD_SOURCE)
+ static pid_t
+ spawnChild(JNIEnv *env, jobject process, ChildStuff *c, const char *helperpath) {
+ pid_t resultPid;
+ jboolean isCopy;
+ int i, offset, rval, bufsize, magic;
+ char *buf, buf1[16];
+ char *hlpargs[2];
+ SpawnInfo sp;
+
+ /* need to tell helper which fd is for receiving the childstuff
+ * and which fd to send response back on
+ */
+ snprintf(buf1, sizeof(buf1), "%d:%d", c->childenv[0], c->fail[1]);
+ /* put the fd string as argument to the helper cmd */
+ hlpargs[0] = buf1;
+ hlpargs[1] = 0;
+
+ /* Following items are sent down the pipe to the helper
+ * after it is spawned.
+ * All strings are null terminated. All arrays of strings
+ * have an empty string for termination.
+ * - the ChildStuff struct
+ * - the SpawnInfo struct
+ * - the argv strings array
+ * - the envv strings array
+ * - the home directory string
+ * - the parentPath string
+ * - the parentPathv array
+ */
+ /* First calculate the sizes */
+ arraysize(c->argv, &sp.nargv, &sp.argvBytes);
+ bufsize = sp.argvBytes;
+ arraysize(c->envv, &sp.nenvv, &sp.envvBytes);
+ bufsize += sp.envvBytes;
+ sp.dirlen = c->pdir == 0 ? 0 : strlen(c->pdir)+1;
+ bufsize += sp.dirlen;
+ arraysize(parentPathv, &sp.nparentPathv, &sp.parentPathvBytes);
+ bufsize += sp.parentPathvBytes;
+ /* We need to clear FD_CLOEXEC if set in the fds[].
+ * Files are created FD_CLOEXEC in Java.
+ * Otherwise, they will be closed when the target gets exec'd */
+ for (i=0; i<3; i++) {
+ if (c->fds[i] != -1) {
+ int flags = fcntl(c->fds[i], F_GETFD);
+ if (flags & FD_CLOEXEC) {
+ fcntl(c->fds[i], F_SETFD, flags & (~1));
+ }
+ }
+ }
+
+ rval = posix_spawn(&resultPid, helperpath, 0, 0, (char * const *) hlpargs, environ);
+
+ if (rval != 0) {
+ return -1;
+ }
+
+ /* now the lengths are known, copy the data */
+ buf = NEW(char, bufsize);
+ if (buf == 0) {
+ return -1;
+ }
+ offset = copystrings(buf, 0, &c->argv[0]);
+ offset = copystrings(buf, offset, &c->envv[0]);
+ memcpy(buf+offset, c->pdir, sp.dirlen);
+ offset += sp.dirlen;
+ offset = copystrings(buf, offset, parentPathv);
+ assert(offset == bufsize);
+
+ magic = magicNumber();
+
+ /* write the two structs and the data buffer */
+ write(c->childenv[1], (char *)&magic, sizeof(magic)); // magic number first
+ write(c->childenv[1], (char *)c, sizeof(*c));
+ write(c->childenv[1], (char *)&sp, sizeof(sp));
+ write(c->childenv[1], buf, bufsize);
+ free(buf);
+
+ /* In this mode an external main() in invoked which calls back into
+ * childProcess() in this file, rather than directly
+ * via the statement below */
+ return resultPid;
+ }
+ #endif
+
+ /*
+ * Start a child process running function childProcess.
+ * This function only returns in the parent.
+ */
+ static pid_t
+ startChild(JNIEnv *env, jobject process, ChildStuff *c, const char *helperpath) {
+ switch (c->mode) {
+ case MODE_VFORK:
+ return vforkChild(c);
+ case MODE_FORK:
+ return forkChild(c);
+ #if defined(__solaris__) || defined(_ALLBSD_SOURCE)
+ case MODE_POSIX_SPAWN:
+ return spawnChild(env, process, c, helperpath);
+ #endif
+ default:
+ return -1;
+ }
+ }
+
JNIEXPORT jint JNICALL
Java_java_lang_UNIXProcess_forkAndExec(JNIEnv *env,
jobject process,
+ jint mode,
+ jbyteArray helperpath,
jbyteArray prog,
jbyteArray argBlock, jint argc,
jbyteArray envBlock, jint envc,
jbyteArray dir,
jintArray std_fds,
jboolean redirectErrorStream)
{
int errnum;
int resultPid = -1;
! int in[2], out[2], err[2], fail[2], childenv[2];
jint *fds = NULL;
+ const char *phelperpath = NULL;
const char *pprog = NULL;
const char *pargBlock = NULL;
const char *penvBlock = NULL;
ChildStuff *c;
in[0] = in[1] = out[0] = out[1] = err[0] = err[1] = fail[0] = fail[1] = -1;
+ childenv[0] = childenv[1] = -1;
if ((c = NEW(ChildStuff, 1)) == NULL) return -1;
c->argv = NULL;
c->envv = NULL;
c->pdir = NULL;
c->clone_stack = NULL;
/* Convert prog + argBlock into a char ** argv.
* Add one word room for expansion of argv for use by
* execve_as_traditional_shell_script.
+ * This word is also used when using spawn mode
*/
assert(prog != NULL && argBlock != NULL);
+ if ((phelperpath = getBytes(env, helperpath)) == NULL) goto Catch;
if ((pprog = getBytes(env, prog)) == NULL) goto Catch;
if ((pargBlock = getBytes(env, argBlock)) == NULL) goto Catch;
if ((c->argv = NEW(const char *, argc + 3)) == NULL) goto Catch;
c->argv[0] = pprog;
+ c->argc = argc + 2;
initVectorFromBlock(c->argv+1, pargBlock, argc);
if (envBlock != NULL) {
/* Convert envBlock into a char ** envv */
if ((penvBlock = getBytes(env, envBlock)) == NULL) goto Catch;
*** 880,889 ****
--- 625,635 ----
if (fds == NULL) goto Catch;
if ((fds[0] == -1 && pipe(in) < 0) ||
(fds[1] == -1 && pipe(out) < 0) ||
(fds[2] == -1 && pipe(err) < 0) ||
+ (pipe(childenv) < 0) ||
(pipe(fail) < 0)) {
throwIOException(env, errno, "Bad file descriptor");
goto Catch;
}
c->fds[0] = fds[0];
*** 892,914 ****
copyPipe(in, c->in);
copyPipe(out, c->out);
copyPipe(err, c->err);
copyPipe(fail, c->fail);
c->redirectErrorStream = redirectErrorStream;
! resultPid = startChild(c);
assert(resultPid != 0);
if (resultPid < 0) {
! throwIOException(env, errno, START_CHILD_SYSTEM_CALL " failed");
goto Catch;
}
- restartableClose(fail[1]); fail[1] = -1; /* See: WhyCantJohnnyExec */
-
switch (readFully(fail[0], &errnum, sizeof(errnum))) {
case 0: break; /* Exec succeeded */
case sizeof(errnum):
waitpid(resultPid, NULL, 0);
throwIOException(env, errnum, "Exec failed");
--- 638,671 ----
copyPipe(in, c->in);
copyPipe(out, c->out);
copyPipe(err, c->err);
copyPipe(fail, c->fail);
+ copyPipe(childenv, c->childenv);
c->redirectErrorStream = redirectErrorStream;
+ c->mode = mode;
! resultPid = startChild(env, process, c, phelperpath);
assert(resultPid != 0);
if (resultPid < 0) {
! switch (c->mode) {
! case MODE_VFORK:
! throwIOException(env, errno, "vfork failed");
! break;
! case MODE_FORK:
! throwIOException(env, errno, "fork failed");
! break;
! case MODE_POSIX_SPAWN:
! throwIOException(env, errno, "spawn failed");
! break;
! }
goto Catch;
}
+ close(fail[1]); fail[1] = -1; /* See: WhyCantJohnnyExec (childproc.c) */
switch (readFully(fail[0], &errnum, sizeof(errnum))) {
case 0: break; /* Exec succeeded */
case sizeof(errnum):
waitpid(resultPid, NULL, 0);
throwIOException(env, errnum, "Exec failed");
*** 921,942 ****
fds[0] = (in [1] != -1) ? in [1] : -1;
fds[1] = (out[0] != -1) ? out[0] : -1;
fds[2] = (err[0] != -1) ? err[0] : -1;
Finally:
- #if START_CHILD_USE_CLONE
free(c->clone_stack);
- #endif
/* Always clean up the child's side of the pipes */
closeSafely(in [0]);
closeSafely(out[1]);
closeSafely(err[1]);
! /* Always clean up fail descriptors */
closeSafely(fail[0]);
closeSafely(fail[1]);
releaseBytes(env, prog, pprog);
releaseBytes(env, argBlock, pargBlock);
releaseBytes(env, envBlock, penvBlock);
releaseBytes(env, dir, c->pdir);
--- 678,699 ----
fds[0] = (in [1] != -1) ? in [1] : -1;
fds[1] = (out[0] != -1) ? out[0] : -1;
fds[2] = (err[0] != -1) ? err[0] : -1;
Finally:
free(c->clone_stack);
/* Always clean up the child's side of the pipes */
closeSafely(in [0]);
closeSafely(out[1]);
closeSafely(err[1]);
! /* Always clean up fail and childEnv descriptors */
closeSafely(fail[0]);
closeSafely(fail[1]);
+ closeSafely(childenv[0]);
+ closeSafely(childenv[1]);
releaseBytes(env, prog, pprog);
releaseBytes(env, argBlock, pargBlock);
releaseBytes(env, envBlock, penvBlock);
releaseBytes(env, dir, c->pdir);
*** 950,962 ****
return resultPid;
Catch:
/* Clean up the parent's side of the pipes in case of failure only */
! closeSafely(in [1]);
! closeSafely(out[0]);
! closeSafely(err[0]);
goto Finally;
}
JNIEXPORT void JNICALL
Java_java_lang_UNIXProcess_destroyProcess(JNIEnv *env, jobject junk, jint pid)
--- 707,719 ----
return resultPid;
Catch:
/* Clean up the parent's side of the pipes in case of failure only */
! closeSafely(in [1]); in[1] = -1;
! closeSafely(out[0]); out[0] = -1;
! closeSafely(err[0]); err[0] = -1;
goto Finally;
}
JNIEXPORT void JNICALL
Java_java_lang_UNIXProcess_destroyProcess(JNIEnv *env, jobject junk, jint pid)