src/main/native/localsocket.cc - bazel - Git at Google

 // Copyright 2014 Google Inc. All rights reserved.
 //
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
 //
 //    http://www.apache.org/licenses/LICENSE-2.0
 //
 // Unless required by applicable law or agreed to in writing, software
 // distributed under the License is distributed on an "AS IS" BASIS,
 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 // See the License for the specific language governing permissions and
 // limitations under the License.

 #include <jni.h>

 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
 #include <poll.h>
 #include <sys/types.h>
 #include <sys/socket.h>
 #include <sys/un.h>

 #include <string>

 #include "src/main/native/unix_jni.h"

 // Returns the field ID for FileDescriptor.fd.
 static jfieldID GetFileDescriptorField(JNIEnv *env) {
   // See http://java.sun.com/docs/books/jni/html/fldmeth.html#26855
   static jclass fd_class = NULL;
   if (fd_class == NULL) { /* note: harmless race condition */
     jclass local = env->FindClass("java/io/FileDescriptor");
     CHECK(local != NULL);
     fd_class = static_cast<jclass>(env->NewGlobalRef(local));
   }
   static jfieldID fieldId = NULL;
   if (fieldId == NULL) { /* note: harmless race condition */
     fieldId = env->GetFieldID(fd_class, "fd", "I");
     CHECK(fieldId != NULL);
   }
   return fieldId;
 }

 // Returns the UNIX filedescriptor from a java.io.FileDescriptor instance.
 static jint GetUnixFileDescriptor(JNIEnv *env, jobject fd_obj) {
   return env->GetIntField(fd_obj, GetFileDescriptorField(env));
 }

 // Sets the UNIX filedescriptor of a java.io.FileDescriptor instance.
 static void SetUnixFileDescriptor(JNIEnv *env, jobject fd_obj, jint fd) {
   env->SetIntField(fd_obj, GetFileDescriptorField(env), fd);
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    socket
  * Signature: (Ljava/io/FileDescriptor;)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_socket(JNIEnv *env,
                                                jclass clazz,
                                                jobject fd_sock) {
   int sock;
   if ((sock = ::socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
     return;
   }
   SetUnixFileDescriptor(env, fd_sock, sock);
 }

 // Initialize "addr" from "name_chars", reporting error and returning
 // false on failure.
 static bool InitializeSockaddr(JNIEnv *env,
                                struct sockaddr_un *addr,
                                const char* name_chars) {
   memset(addr, 0, sizeof *addr);
   addr->sun_family = AF_UNIX;
   // Note: UNIX_PATH_MAX is quite small!
   if (strlen(name_chars) >= sizeof(addr->sun_path)) {
     ::PostFileException(env, ENAMETOOLONG, name_chars);
     return false;
   }
   strcpy((char*) &addr->sun_path, name_chars);
   return true;
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    bind
  * Signature: (Ljava/io/FileDescriptor;Ljava/lang/String;)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_bind(JNIEnv *env,
                                              jclass clazz,
                                              jobject fd_svr,
                                              jstring name) {
   int svr_sock = GetUnixFileDescriptor(env, fd_svr);
   const char* name_chars = env->GetStringUTFChars(name, NULL);
   struct sockaddr_un addr;
   if (InitializeSockaddr(env, &addr, name_chars) &&
       ::bind(svr_sock, (struct sockaddr *) &addr, sizeof addr) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
   }
   env->ReleaseStringUTFChars(name, name_chars);
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    listen
  * Signature: (Ljava/io/FileDescriptor;I)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_listen(JNIEnv *env,
                                                jclass clazz,
                                                jobject fd_svr,
                                                jint backlog) {
   int svr_sock = GetUnixFileDescriptor(env, fd_svr);
   if (::listen(svr_sock, backlog) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
   }
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    select
  * Signature: (L[java/io/FileDescriptor;[java/io/FileDescriptor;[java/io/FileDescriptor;J)Ljava/io/FileDescriptor
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_poll(JNIEnv *env,
                                                jclass clazz,
                                                jobject rfds_svr,
                                                jlong timeoutMillis) {
   // TODO(bazel-team): Handle Unix signals, namely SIGTERM.

   // Copy Java FD into pollfd
   pollfd pollfd;
   pollfd.fd = GetUnixFileDescriptor(env, rfds_svr);
   pollfd.events = POLLIN;
   pollfd.revents = 0;

   int count = poll(&pollfd, 1, timeoutMillis);
   if (count == 0) {
     // throws a timeout exception.
     ::PostException(env, ETIMEDOUT, ::ErrorMessage(ETIMEDOUT));
   } else if (count < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
   }
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    accept
  * Signature: (Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_accept(JNIEnv *env,
                                                jclass clazz,
                                                jobject fd_svr,
                                                jobject fd_cli) {
   int svr_sock = GetUnixFileDescriptor(env, fd_svr);
   int cli_sock;
   if ((cli_sock = ::accept(svr_sock, NULL, NULL)) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
     return;
   }
   SetUnixFileDescriptor(env, fd_cli, cli_sock);
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    close
  * Signature: (Ljava/io/FileDescriptor;)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_close(JNIEnv *env,
                                               jclass clazz,
                                               jobject fd_svr) {
   int svr_sock = GetUnixFileDescriptor(env, fd_svr);
   if (::close(svr_sock) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
   }
   SetUnixFileDescriptor(env, fd_svr, -1);
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    connect
  * Signature: (Ljava/io/FileDescriptor;Ljava/lang/String;)V
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_connect(JNIEnv *env,
                                                 jclass clazz,
                                                 jobject fd_cli,
                                                 jstring name) {
   const char* name_chars = env->GetStringUTFChars(name, NULL);
   jint cli_sock = GetUnixFileDescriptor(env, fd_cli);
   if (cli_sock == -1) {
     ::PostFileException(env, ENOTSOCK, name_chars);
   } else {
     struct sockaddr_un addr;
     if (InitializeSockaddr(env, &addr, name_chars)) {
       if (::connect(cli_sock, (struct sockaddr *) &addr, sizeof addr) < 0) {
         ::PostException(env, errno, ::ErrorMessage(errno));
       }
     }
   }
   env->ReleaseStringUTFChars(name, name_chars);
 }

 /*
  * Class:     com.google.devtools.build.lib.unix.LocalSocket
  * Method:    shutdown()
  * Signature: (Ljava/io/FileDescriptor;I)V
  * Parameters: code: 0 to shutdown input and 1 to shutdown output.
  */
 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocket_shutdown(JNIEnv *env,
                                                  jclass clazz,
                                                  jobject fd,
                                                  jint code) {
   int action;
   if (code == 0) {
     action = SHUT_RD;
   } else {
     CHECK(code == 1);
     action = SHUT_WR;
   }

   int sock = GetUnixFileDescriptor(env, fd);
   if (shutdown(sock, action) < 0) {
     ::PostException(env, errno, ::ErrorMessage(errno));
   }
 }

 // TODO(bazel-team): These methods were removed in JDK8, so they
 // can be removed when we are no longer using JDK7.  See note in
 // LocalSocketImpl.
 static jmethodID increment_use_count_;
 static jmethodID decrement_use_count_;

 // >=JDK8
 static jmethodID fd_attach_;
 static jmethodID fd_close_all_;

 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocketImpl_init(JNIEnv *env, jclass ignored) {
   jclass cls = env->FindClass("java/io/FileDescriptor");
   if (cls == NULL) {
     cls = env->FindClass("java/lang/NoClassDefFoundError");
     env->ThrowNew(cls, "FileDescriptor class not found");
     return;
   }

   // JDK7
   increment_use_count_ =
       env->GetMethodID(cls, "incrementAndGetUseCount", "()I");
   if (increment_use_count_ != NULL) {
     decrement_use_count_ =
         env->GetMethodID(cls, "decrementAndGetUseCount", "()I");
   } else {
     // JDK8
     env->ExceptionClear();  // The pending exception from increment_use_count_

     fd_attach_ = env->GetMethodID(cls, "attach", "(Ljava/io/Closeable;)V");
     fd_close_all_ = env->GetMethodID(cls, "closeAll", "(Ljava/io/Closeable;)V");

     if (fd_attach_ == NULL || fd_close_all_ == NULL) {
       cls = env->FindClass("java/lang/NoSuchMethodError");
       env->ThrowNew(cls, "FileDescriptor methods not found");
       return;
     }
   }
 }

 extern "C" JNIEXPORT void JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocketImpl_ref(JNIEnv *env, jclass clazz,
                                                 jobject fd, jobject closer) {
   if (increment_use_count_ != NULL) {
     env->CallIntMethod(fd, increment_use_count_);
   }

   if (fd_attach_ != NULL) {
     env->CallVoidMethod(fd, fd_attach_, closer);
   }
 }

 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocketImpl_unref(JNIEnv *env, jclass clazz,
                                                   jobject fd) {
   if (decrement_use_count_ != NULL) {
     env->CallIntMethod(fd, decrement_use_count_);
     return true;
   }
   return false;
 }

 extern "C" JNIEXPORT jboolean JNICALL
 Java_com_google_devtools_build_lib_unix_LocalSocketImpl_close0(JNIEnv *env, jclass clazz,
                                                    jobject fd,
                                                    jobject closeable) {
   if (fd_close_all_ != NULL) {
     env->CallVoidMethod(fd, fd_close_all_, closeable);
     return true;
   }
   // This will happen if fd_close_all_ is NULL, which means we are running in
   // <=JDK7, which means that the caller needs to invoke close() explicitly.
   return false;
 }
	// Copyright 2014 Google Inc. All rights reserved.
	//
	// Licensed under the Apache License, Version 2.0 (the "License");
	// you may not use this file except in compliance with the License.
	// You may obtain a copy of the License at
	//
	// http://www.apache.org/licenses/LICENSE-2.0
	//
	// Unless required by applicable law or agreed to in writing, software
	// distributed under the License is distributed on an "AS IS" BASIS,
	// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	// See the License for the specific language governing permissions and
	// limitations under the License.

	#include <jni.h>

	#include <errno.h>
	#include <stdio.h>
	#include <stdlib.h>
	#include <string.h>
	#include <unistd.h>
	#include <poll.h>
	#include <sys/types.h>
	#include <sys/socket.h>
	#include <sys/un.h>

	#include <string>

	#include "src/main/native/unix_jni.h"

	// Returns the field ID for FileDescriptor.fd.
	static jfieldID GetFileDescriptorField(JNIEnv *env) {
	// See http://java.sun.com/docs/books/jni/html/fldmeth.html#26855
	static jclass fd_class = NULL;
	if (fd_class == NULL) { /* note: harmless race condition */
	jclass local = env->FindClass("java/io/FileDescriptor");
	CHECK(local != NULL);
	fd_class = static_cast<jclass>(env->NewGlobalRef(local));
	}
	static jfieldID fieldId = NULL;
	if (fieldId == NULL) { /* note: harmless race condition */
	fieldId = env->GetFieldID(fd_class, "fd", "I");
	CHECK(fieldId != NULL);
	}
	return fieldId;
	}

	// Returns the UNIX filedescriptor from a java.io.FileDescriptor instance.
	static jint GetUnixFileDescriptor(JNIEnv *env, jobject fd_obj) {
	return env->GetIntField(fd_obj, GetFileDescriptorField(env));
	}

	// Sets the UNIX filedescriptor of a java.io.FileDescriptor instance.
	static void SetUnixFileDescriptor(JNIEnv *env, jobject fd_obj, jint fd) {
	env->SetIntField(fd_obj, GetFileDescriptorField(env), fd);
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: socket
	* Signature: (Ljava/io/FileDescriptor;)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_socket(JNIEnv *env,
	jclass clazz,
	jobject fd_sock) {
	int sock;
	if ((sock = ::socket(AF_UNIX, SOCK_STREAM, 0)) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	return;
	}
	SetUnixFileDescriptor(env, fd_sock, sock);
	}

	// Initialize "addr" from "name_chars", reporting error and returning
	// false on failure.
	static bool InitializeSockaddr(JNIEnv *env,
	struct sockaddr_un *addr,
	const char* name_chars) {
	memset(addr, 0, sizeof *addr);
	addr->sun_family = AF_UNIX;
	// Note: UNIX_PATH_MAX is quite small!
	if (strlen(name_chars) >= sizeof(addr->sun_path)) {
	::PostFileException(env, ENAMETOOLONG, name_chars);
	return false;
	}
	strcpy((char*) &addr->sun_path, name_chars);
	return true;
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: bind
	* Signature: (Ljava/io/FileDescriptor;Ljava/lang/String;)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_bind(JNIEnv *env,
	jclass clazz,
	jobject fd_svr,
	jstring name) {
	int svr_sock = GetUnixFileDescriptor(env, fd_svr);
	const char* name_chars = env->GetStringUTFChars(name, NULL);
	struct sockaddr_un addr;
	if (InitializeSockaddr(env, &addr, name_chars) &&
	::bind(svr_sock, (struct sockaddr *) &addr, sizeof addr) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	env->ReleaseStringUTFChars(name, name_chars);
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: listen
	* Signature: (Ljava/io/FileDescriptor;I)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_listen(JNIEnv *env,
	jclass clazz,
	jobject fd_svr,
	jint backlog) {
	int svr_sock = GetUnixFileDescriptor(env, fd_svr);
	if (::listen(svr_sock, backlog) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: select
	* Signature: (L[java/io/FileDescriptor;[java/io/FileDescriptor;[java/io/FileDescriptor;J)Ljava/io/FileDescriptor
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_poll(JNIEnv *env,
	jclass clazz,
	jobject rfds_svr,
	jlong timeoutMillis) {
	// TODO(bazel-team): Handle Unix signals, namely SIGTERM.

	// Copy Java FD into pollfd
	pollfd pollfd;
	pollfd.fd = GetUnixFileDescriptor(env, rfds_svr);
	pollfd.events = POLLIN;
	pollfd.revents = 0;

	int count = poll(&pollfd, 1, timeoutMillis);
	if (count == 0) {
	// throws a timeout exception.
	::PostException(env, ETIMEDOUT, ::ErrorMessage(ETIMEDOUT));
	} else if (count < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: accept
	* Signature: (Ljava/io/FileDescriptor;Ljava/io/FileDescriptor;)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_accept(JNIEnv *env,
	jclass clazz,
	jobject fd_svr,
	jobject fd_cli) {
	int svr_sock = GetUnixFileDescriptor(env, fd_svr);
	int cli_sock;
	if ((cli_sock = ::accept(svr_sock, NULL, NULL)) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	return;
	}
	SetUnixFileDescriptor(env, fd_cli, cli_sock);
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: close
	* Signature: (Ljava/io/FileDescriptor;)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_close(JNIEnv *env,
	jclass clazz,
	jobject fd_svr) {
	int svr_sock = GetUnixFileDescriptor(env, fd_svr);
	if (::close(svr_sock) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	SetUnixFileDescriptor(env, fd_svr, -1);
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: connect
	* Signature: (Ljava/io/FileDescriptor;Ljava/lang/String;)V
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_connect(JNIEnv *env,
	jclass clazz,
	jobject fd_cli,
	jstring name) {
	const char* name_chars = env->GetStringUTFChars(name, NULL);
	jint cli_sock = GetUnixFileDescriptor(env, fd_cli);
	if (cli_sock == -1) {
	::PostFileException(env, ENOTSOCK, name_chars);
	} else {
	struct sockaddr_un addr;
	if (InitializeSockaddr(env, &addr, name_chars)) {
	if (::connect(cli_sock, (struct sockaddr *) &addr, sizeof addr) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	}
	}
	env->ReleaseStringUTFChars(name, name_chars);
	}

	/*
	* Class: com.google.devtools.build.lib.unix.LocalSocket
	* Method: shutdown()
	* Signature: (Ljava/io/FileDescriptor;I)V
	* Parameters: code: 0 to shutdown input and 1 to shutdown output.
	*/
	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocket_shutdown(JNIEnv *env,
	jclass clazz,
	jobject fd,
	jint code) {
	int action;
	if (code == 0) {
	action = SHUT_RD;
	} else {
	CHECK(code == 1);
	action = SHUT_WR;
	}

	int sock = GetUnixFileDescriptor(env, fd);
	if (shutdown(sock, action) < 0) {
	::PostException(env, errno, ::ErrorMessage(errno));
	}
	}

	// TODO(bazel-team): These methods were removed in JDK8, so they
	// can be removed when we are no longer using JDK7. See note in
	// LocalSocketImpl.
	static jmethodID increment_use_count_;
	static jmethodID decrement_use_count_;

	// >=JDK8
	static jmethodID fd_attach_;
	static jmethodID fd_close_all_;

	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocketImpl_init(JNIEnv *env, jclass ignored) {
	jclass cls = env->FindClass("java/io/FileDescriptor");
	if (cls == NULL) {
	cls = env->FindClass("java/lang/NoClassDefFoundError");
	env->ThrowNew(cls, "FileDescriptor class not found");
	return;
	}

	// JDK7
	increment_use_count_ =
	env->GetMethodID(cls, "incrementAndGetUseCount", "()I");
	if (increment_use_count_ != NULL) {
	decrement_use_count_ =
	env->GetMethodID(cls, "decrementAndGetUseCount", "()I");
	} else {
	// JDK8
	env->ExceptionClear(); // The pending exception from increment_use_count_

	fd_attach_ = env->GetMethodID(cls, "attach", "(Ljava/io/Closeable;)V");
	fd_close_all_ = env->GetMethodID(cls, "closeAll", "(Ljava/io/Closeable;)V");

	if (fd_attach_ == NULL \|\| fd_close_all_ == NULL) {
	cls = env->FindClass("java/lang/NoSuchMethodError");
	env->ThrowNew(cls, "FileDescriptor methods not found");
	return;
	}
	}
	}

	extern "C" JNIEXPORT void JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocketImpl_ref(JNIEnv *env, jclass clazz,
	jobject fd, jobject closer) {
	if (increment_use_count_ != NULL) {
	env->CallIntMethod(fd, increment_use_count_);
	}

	if (fd_attach_ != NULL) {
	env->CallVoidMethod(fd, fd_attach_, closer);
	}
	}

	extern "C" JNIEXPORT jboolean JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocketImpl_unref(JNIEnv *env, jclass clazz,
	jobject fd) {
	if (decrement_use_count_ != NULL) {
	env->CallIntMethod(fd, decrement_use_count_);
	return true;
	}
	return false;
	}

	extern "C" JNIEXPORT jboolean JNICALL
	Java_com_google_devtools_build_lib_unix_LocalSocketImpl_close0(JNIEnv *env, jclass clazz,
	jobject fd,
	jobject closeable) {
	if (fd_close_all_ != NULL) {
	env->CallVoidMethod(fd, fd_close_all_, closeable);
	return true;
	}
	// This will happen if fd_close_all_ is NULL, which means we are running in
	// <=JDK7, which means that the caller needs to invoke close() explicitly.
	return false;
	}