src/java.base/share/native/libjava/io_util.c

*** 120,129 ****
--- 120,226 ----
          free(buf);
      }
      return nread;
  }
  
+ jint
+ readBytesD(JNIEnv *env, jobject this, jbyteArray bytes,
+           jint off, jint len, jfieldID fid, jfieldID pgsz_id)
+ {
+ #ifdef _WIN32
+     JNU_ThrowIOException(env, "DirectIO is not supported on Windows platform!");
+ #else
+     jint nread;
+     void *buf = NULL;
+     int delta = 0;
+     int gap = 0;
+     int newLen = 0;
+     long currentLocation;
+     long newStartLocation;
+     FD fd;
+     int pageSize;
+     if (IS_NULL(bytes)) {
+         JNU_ThrowNullPointerException(env, NULL);
+         return -1;
+     }
+ 
+     if (outOfBounds(env, off, len, bytes)) {
+         JNU_ThrowByName(env, "java/lang/IndexOutOfBoundsException", NULL);
+         return -1;
+     }
+ 
+     if (len == 0) {
+         return 0;
+     }
+ 
+     fd = GET_FD(this, fid);
+     pageSize = GET_PG_SIZE(this, pgsz_id);
+     
+     if (fd == -1) {
+         JNU_ThrowIOException(env, "Stream Closed");
+         return -1;
+     } else if (pageSize == -1) {
+         JNU_ThrowIOException(env, "Error getting kernel pageSize for DirectIO alligment");
+         return -1;
+     } else {
+         currentLocation = IO_Lseek(fd, 0, SEEK_CUR);
+ 
+         if ((currentLocation % pageSize) != 0) {
+             newStartLocation = currentLocation / pageSize * pageSize;
+             gap = currentLocation - newStartLocation;
+         } else {
+             newStartLocation = currentLocation;
+             gap = 0;
+         }
+         IO_Lseek(fd, newStartLocation, SEEK_SET);
+         if ((len % pageSize) != 0) {
+             newLen = (len / pageSize + 1) * pageSize;
+         } else {
+             newLen = len;
+         }
+         if ((newLen - gap) < len) {
+             newLen = newLen + pageSize;
+         }
+ 
+         delta = newLen - len;
+         if (newLen == 0) {
+             return 0;
+         } else {
+             posix_memalign(&buf, pageSize, newLen);
+             if (buf == NULL) {
+                 JNU_ThrowOutOfMemoryError(env, NULL);
+                 return 0;
+             }
+         }
+         nread = IO_Read(fd, buf, newLen);
+         if (nread > 0) {
+               if (nread >= len) {
+                   (*env)->SetByteArrayRegion(env, bytes, off, len, ((jbyte *)(buf) + gap));    //read in the middle of a file
+               } else {
+                   (*env)->SetByteArrayRegion(env, bytes, off, (nread-gap), ((jbyte *)(buf) + gap));    //reached the end of the file
+               }
+         } else if (nread == -1) {
+             JNU_ThrowIOExceptionWithLastError(env, "Read error");
+         } else { /*EOF*/
+             nread = -1;
+         }
+         IO_Lseek(fd, (currentLocation + len), SEEK_SET);
+ 
+         free(buf);
+         if (nread != -1) {
+             if (nread >= len) {
+                 return len;
+             } else {
+                 return (nread - gap);
+             }
+         } else {
+             return -1;
+         }
+     }
+ #endif
+ }
+ 
  void
  writeSingle(JNIEnv *env, jobject this, jint byte, jboolean append, jfieldID fid) {
      // Discard the 24 high-order bits of byte. See OutputStream#write(int)
      char c = (char) byte;
      jint n;
*** 200,209 ****
--- 297,378 ----
          free(buf);
      }
  }
  
  void
+ writeBytesD(JNIEnv *env, jobject this, jbyteArray bytes,
+            jint off, jint len, jboolean append, jfieldID fid, jfieldID pgsz_id)
+ {
+ #ifdef _WIN32
+     JNU_ThrowIOException(env, "DirectIO is not supported on Windows platform!");
+ #else
+     jint n;
+     void *buf = NULL;
+     FD fd;
+     int pageSize;
+     long currentLocation;
+ 
+     fd = GET_FD(this, fid);
+     if (fd == -1) {
+         JNU_ThrowIOException(env, "Stream Closed");
+     }
+ 
+     pageSize = GET_PG_SIZE(this, pgsz_id);
+     if (pageSize == -1) {
+         JNU_ThrowIOException(env, "Error getting kernel pageSize for DirectIO alligment");
+     }
+ 
+     currentLocation = IO_Lseek(fd, 0, SEEK_CUR);
+ 
+     if ((len % pageSize != 0) || (currentLocation % pageSize != 0)) {
+         JNU_ThrowIOException(env, 
+             "In DirectIO mode, the IO size and currentLocation must be aligned with kernel page size!");
+     }
+ 
+     if (IS_NULL(bytes)) {
+         JNU_ThrowNullPointerException(env, NULL);
+         return;
+     }
+ 
+     if (outOfBounds(env, off, len, bytes)) {
+         JNU_ThrowByName(env, "java/lang/IndexOutOfBoundsException", NULL);
+         return;
+     }
+ 
+     if (len == 0) {
+         return;
+     } else {
+         posix_memalign(&buf, pageSize, len);
+         if (buf == NULL) {
+             JNU_ThrowOutOfMemoryError(env, NULL);
+             return;
+         }
+     }
+ 
+     (*env)->GetByteArrayRegion(env, bytes, off, len, (jbyte *)buf);
+ 
+     if (!(*env)->ExceptionOccurred(env)) {
+         off = 0;
+         while (len > 0) {
+             if (append == JNI_TRUE) {
+                 n = IO_Append(fd, buf+off, len);
+             } else {
+                 n = IO_Write(fd, buf+off, len);
+             }
+             if (n == -1) {
+                 JNU_ThrowIOExceptionWithLastError(env, "Write error");
+                 break;
+             }
+             off += n;
+             len -= n;
+         }
+     }
+     free(buf);
+ #endif
+ }
+ 
+ void
  throwFileNotFoundException(JNIEnv *env, jstring path)
  {
      char buf[256];
      size_t n;
      jobject x;