30 import java.nio.ByteBuffer;
31
32
33 /**
34 * File-descriptor based I/O utilities that are shared by NIO classes.
35 */
36
37 public class IOUtil {
38
39 /**
40 * Max number of iovec structures that readv/writev supports
41 */
42 static final int IOV_MAX;
43
44 private IOUtil() { } // No instantiation
45
46 static int write(FileDescriptor fd, ByteBuffer src, long position,
47 NativeDispatcher nd)
48 throws IOException
49 {
50 if (src instanceof DirectBuffer)
51 return writeFromNativeBuffer(fd, src, position, nd);
52
53 // Substitute a native buffer
54 int pos = src.position();
55 int lim = src.limit();
56 assert (pos <= lim);
57 int rem = (pos <= lim ? lim - pos : 0);
58 ByteBuffer bb = Util.getTemporaryDirectBuffer(rem);
59 try {
60 bb.put(src);
61 bb.flip();
62 // Do not update src until we see how many bytes were written
63 src.position(pos);
64
65 int n = writeFromNativeBuffer(fd, bb, position, nd);
66 if (n > 0) {
67 // now update src
68 src.position(pos + n);
69 }
70 return n;
71 } finally {
72 Util.offerFirstTemporaryDirectBuffer(bb);
73 }
74 }
75
76 private static int writeFromNativeBuffer(FileDescriptor fd, ByteBuffer bb,
77 long position, NativeDispatcher nd)
78 throws IOException
79 {
80 int pos = bb.position();
81 int lim = bb.limit();
82 assert (pos <= lim);
83 int rem = (pos <= lim ? lim - pos : 0);
84
85 int written = 0;
86 if (rem == 0)
87 return 0;
88 if (position != -1) {
89 written = nd.pwrite(fd,
90 ((DirectBuffer)bb).address() + pos,
91 rem, position);
92 } else {
93 written = nd.write(fd, ((DirectBuffer)bb).address() + pos, rem);
94 }
95 if (written > 0)
96 bb.position(pos + written);
97 return written;
98 }
99
100 static long write(FileDescriptor fd, ByteBuffer[] bufs, NativeDispatcher nd)
101 throws IOException
102 {
103 return write(fd, bufs, 0, bufs.length, nd);
104 }
105
106 static long write(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
107 NativeDispatcher nd)
108 throws IOException
109 {
110 IOVecWrapper vec = IOVecWrapper.get(length);
111
112 boolean completed = false;
113 int iov_len = 0;
114 try {
115
116 // Iterate over buffers to populate native iovec array.
117 int count = offset + length;
118 int i = offset;
119 while (i < count && iov_len < IOV_MAX) {
120 ByteBuffer buf = bufs[i];
121 int pos = buf.position();
122 int lim = buf.limit();
123 assert (pos <= lim);
124 int rem = (pos <= lim ? lim - pos : 0);
125 if (rem > 0) {
126 vec.setBuffer(iov_len, buf, pos, rem);
127
128 // allocate shadow buffer to ensure I/O is done with direct buffer
129 if (!(buf instanceof DirectBuffer)) {
130 ByteBuffer shadow = Util.getTemporaryDirectBuffer(rem);
131 shadow.put(buf);
132 shadow.flip();
133 vec.setShadow(iov_len, shadow);
134 buf.position(pos); // temporarily restore position in user buffer
135 buf = shadow;
136 pos = shadow.position();
137 }
138
139 vec.putBase(iov_len, ((DirectBuffer)buf).address() + pos);
140 vec.putLen(iov_len, rem);
141 iov_len++;
142 }
143 i++;
144 }
145 if (iov_len == 0)
146 return 0L;
147
148 long bytesWritten = nd.writev(fd, vec.address, iov_len);
149
150 // Notify the buffers how many bytes were taken
169 return bytesWritten;
170
171 } finally {
172 // if an error occurred then clear refs to buffers and return any shadow
173 // buffers to cache
174 if (!completed) {
175 for (int j=0; j<iov_len; j++) {
176 ByteBuffer shadow = vec.getShadow(j);
177 if (shadow != null)
178 Util.offerLastTemporaryDirectBuffer(shadow);
179 vec.clearRefs(j);
180 }
181 }
182 }
183 }
184
185 static int read(FileDescriptor fd, ByteBuffer dst, long position,
186 NativeDispatcher nd)
187 throws IOException
188 {
189 if (dst.isReadOnly())
190 throw new IllegalArgumentException("Read-only buffer");
191 if (dst instanceof DirectBuffer)
192 return readIntoNativeBuffer(fd, dst, position, nd);
193
194 // Substitute a native buffer
195 ByteBuffer bb = Util.getTemporaryDirectBuffer(dst.remaining());
196 try {
197 int n = readIntoNativeBuffer(fd, bb, position, nd);
198 bb.flip();
199 if (n > 0)
200 dst.put(bb);
201 return n;
202 } finally {
203 Util.offerFirstTemporaryDirectBuffer(bb);
204 }
205 }
206
207 private static int readIntoNativeBuffer(FileDescriptor fd, ByteBuffer bb,
208 long position, NativeDispatcher nd)
209 throws IOException
210 {
211 int pos = bb.position();
212 int lim = bb.limit();
213 assert (pos <= lim);
214 int rem = (pos <= lim ? lim - pos : 0);
215
216 if (rem == 0)
217 return 0;
218 int n = 0;
219 if (position != -1) {
220 n = nd.pread(fd, ((DirectBuffer)bb).address() + pos,
221 rem, position);
222 } else {
223 n = nd.read(fd, ((DirectBuffer)bb).address() + pos, rem);
224 }
225 if (n > 0)
226 bb.position(pos + n);
227 return n;
228 }
229
230 static long read(FileDescriptor fd, ByteBuffer[] bufs, NativeDispatcher nd)
231 throws IOException
232 {
233 return read(fd, bufs, 0, bufs.length, nd);
234 }
235
236 static long read(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
237 NativeDispatcher nd)
238 throws IOException
239 {
240 IOVecWrapper vec = IOVecWrapper.get(length);
241
242 boolean completed = false;
243 int iov_len = 0;
244 try {
245
246 // Iterate over buffers to populate native iovec array.
247 int count = offset + length;
248 int i = offset;
249 while (i < count && iov_len < IOV_MAX) {
250 ByteBuffer buf = bufs[i];
251 if (buf.isReadOnly())
252 throw new IllegalArgumentException("Read-only buffer");
253 int pos = buf.position();
254 int lim = buf.limit();
255 assert (pos <= lim);
256 int rem = (pos <= lim ? lim - pos : 0);
257
258 if (rem > 0) {
259 vec.setBuffer(iov_len, buf, pos, rem);
260
261 // allocate shadow buffer to ensure I/O is done with direct buffer
262 if (!(buf instanceof DirectBuffer)) {
263 ByteBuffer shadow = Util.getTemporaryDirectBuffer(rem);
264 vec.setShadow(iov_len, shadow);
265 buf = shadow;
266 pos = shadow.position();
267 }
268
269 vec.putBase(iov_len, ((DirectBuffer)buf).address() + pos);
270 vec.putLen(iov_len, rem);
271 iov_len++;
272 }
273 i++;
274 }
275 if (iov_len == 0)
276 return 0L;
277
278 long bytesRead = nd.readv(fd, vec.address, iov_len);
279
280 // Notify the buffers how many bytes were read
281 long left = bytesRead;
282 for (int j=0; j<iov_len; j++) {
283 ByteBuffer shadow = vec.getShadow(j);
|
30 import java.nio.ByteBuffer;
31
32
33 /**
34 * File-descriptor based I/O utilities that are shared by NIO classes.
35 */
36
37 public class IOUtil {
38
39 /**
40 * Max number of iovec structures that readv/writev supports
41 */
42 static final int IOV_MAX;
43
44 private IOUtil() { } // No instantiation
45
46 static int write(FileDescriptor fd, ByteBuffer src, long position,
47 NativeDispatcher nd)
48 throws IOException
49 {
50 return write(fd, src, position, false, -1, nd);
51 }
52
53 static int write(FileDescriptor fd, ByteBuffer src, long position,
54 boolean directIO, int alignment, NativeDispatcher nd)
55 throws IOException
56 {
57 if (src instanceof DirectBuffer) {
58 return writeFromNativeBuffer(fd, src, position, directIO, alignment, nd);
59 }
60
61 // Substitute a native buffer
62 int pos = src.position();
63 int lim = src.limit();
64 assert (pos <= lim);
65 int rem = (pos <= lim ? lim - pos : 0);
66 ByteBuffer bb;
67 if (directIO) {
68 if (rem % alignment != 0)
69 throw new IllegalArgumentException("DirectByteBuffer is not properly aligned");
70 bb = Util.getTemporaryAlignedDirectBuffer(rem, alignment);
71 } else {
72 bb = Util.getTemporaryDirectBuffer(rem);
73 }
74 try {
75 bb.put(src);
76 bb.flip();
77 // Do not update src until we see how many bytes were written
78 src.position(pos);
79
80 int n = writeFromNativeBuffer(fd, bb, position, directIO, alignment, nd);
81 if (n > 0) {
82 // now update src
83 src.position(pos + n);
84 }
85 return n;
86 } finally {
87 Util.offerFirstTemporaryDirectBuffer(bb);
88 }
89 }
90
91 private static int writeFromNativeBuffer(FileDescriptor fd, ByteBuffer bb, long position,
92 boolean directIO, int alignment, NativeDispatcher nd)
93 throws IOException
94 {
95 int pos = bb.position();
96 int lim = bb.limit();
97 assert (pos <= lim);
98 int rem = (pos <= lim ? lim - pos : 0);
99
100 if (directIO && (bb.alignmentOffset(pos, alignment) != 0) && (rem % alignment != 0)) {
101 throw new IllegalArgumentException("DirectByteBuffer is not properly aligned");
102 }
103
104 int written = 0;
105 if (rem == 0)
106 return 0;
107 if (position != -1) {
108 written = nd.pwrite(fd,
109 ((DirectBuffer)bb).address() + pos,
110 rem, position);
111 } else {
112 written = nd.write(fd, ((DirectBuffer)bb).address() + pos, rem);
113 }
114 if (written > 0)
115 bb.position(pos + written);
116 return written;
117 }
118
119 static long write(FileDescriptor fd, ByteBuffer[] bufs, NativeDispatcher nd)
120 throws IOException
121 {
122 return write(fd, bufs, 0, bufs.length, false, -1, nd);
123 }
124
125 static long write(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
126 NativeDispatcher nd)
127 throws IOException
128 {
129 return write(fd, bufs, offset, length, false, -1, nd);
130 }
131
132 static long write(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
133 boolean directIO, int alignment, NativeDispatcher nd)
134 throws IOException
135 {
136 IOVecWrapper vec = IOVecWrapper.get(length);
137
138 boolean completed = false;
139 int iov_len = 0;
140 try {
141
142 // Iterate over buffers to populate native iovec array.
143 int count = offset + length;
144 int i = offset;
145 while (i < count && iov_len < IOV_MAX) {
146 ByteBuffer buf = bufs[i];
147 int pos = buf.position();
148 int lim = buf.limit();
149 assert (pos <= lim);
150 int rem = (pos <= lim ? lim - pos : 0);
151 if (directIO && (rem % alignment != 0))
152 throw new IllegalArgumentException("IO size or position is not aligned");
153
154 if (rem > 0) {
155 vec.setBuffer(iov_len, buf, pos, rem);
156
157 // allocate shadow buffer to ensure I/O is done with direct buffer
158 if (!(buf instanceof DirectBuffer)) {
159 ByteBuffer shadow;
160 if (directIO)
161 shadow = Util.getTemporaryAlignedDirectBuffer(rem, alignment);
162 else
163 shadow = Util.getTemporaryDirectBuffer(rem);
164 shadow.put(buf);
165 shadow.flip();
166 vec.setShadow(iov_len, shadow);
167 buf.position(pos); // temporarily restore position in user buffer
168 buf = shadow;
169 pos = shadow.position();
170 }
171
172 vec.putBase(iov_len, ((DirectBuffer)buf).address() + pos);
173 vec.putLen(iov_len, rem);
174 iov_len++;
175 }
176 i++;
177 }
178 if (iov_len == 0)
179 return 0L;
180
181 long bytesWritten = nd.writev(fd, vec.address, iov_len);
182
183 // Notify the buffers how many bytes were taken
202 return bytesWritten;
203
204 } finally {
205 // if an error occurred then clear refs to buffers and return any shadow
206 // buffers to cache
207 if (!completed) {
208 for (int j=0; j<iov_len; j++) {
209 ByteBuffer shadow = vec.getShadow(j);
210 if (shadow != null)
211 Util.offerLastTemporaryDirectBuffer(shadow);
212 vec.clearRefs(j);
213 }
214 }
215 }
216 }
217
218 static int read(FileDescriptor fd, ByteBuffer dst, long position,
219 NativeDispatcher nd)
220 throws IOException
221 {
222 return read(fd, dst, position, false, -1, nd);
223 }
224
225 static int read(FileDescriptor fd, ByteBuffer dst, long position,
226 boolean directIO, int alignment, NativeDispatcher nd)
227 throws IOException
228 {
229 if (dst.isReadOnly())
230 throw new IllegalArgumentException("Read-only buffer");
231 if (dst instanceof DirectBuffer)
232 return readIntoNativeBuffer(fd, dst, position, directIO, alignment, nd);
233
234 // Substitute a native buffer
235 ByteBuffer bb;
236 if (directIO) {
237 if (dst.remaining() % alignment != 0)
238 throw new IllegalArgumentException("DirectByteBuffer is not properly aligned");
239 bb = Util.getTemporaryAlignedDirectBuffer(dst.remaining(), alignment);
240 } else {
241 bb = Util.getTemporaryDirectBuffer(dst.remaining());
242 }
243 try {
244 int n = readIntoNativeBuffer(fd, bb, position, directIO, alignment,nd);
245 bb.flip();
246 if (n > 0)
247 dst.put(bb);
248 return n;
249 } finally {
250 Util.offerFirstTemporaryDirectBuffer(bb);
251 }
252 }
253
254 private static int readIntoNativeBuffer(FileDescriptor fd, ByteBuffer bb, long position,
255 boolean directIO, int alignment, NativeDispatcher nd)
256 throws IOException
257 {
258 int pos = bb.position();
259 int lim = bb.limit();
260 assert (pos <= lim);
261 int rem = (pos <= lim ? lim - pos : 0);
262
263 if(directIO && !(bb.alignmentOffset(pos, alignment) != 0) && (rem % alignment != 0))
264 throw new IllegalArgumentException("DirectByteBuffer is not properly aligned");
265
266 if (rem == 0)
267 return 0;
268 int n = 0;
269 if (position != -1) {
270 n = nd.pread(fd, ((DirectBuffer)bb).address() + pos,
271 rem, position);
272 } else {
273 n = nd.read(fd, ((DirectBuffer)bb).address() + pos, rem);
274 }
275 if (n > 0)
276 bb.position(pos + n);
277 return n;
278 }
279
280 static long read(FileDescriptor fd, ByteBuffer[] bufs, NativeDispatcher nd)
281 throws IOException
282 {
283 return read(fd, bufs, 0, bufs.length, false, -1, nd);
284 }
285
286 static long read(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
287 NativeDispatcher nd)
288 throws IOException
289 {
290 return read(fd, bufs, offset, bufs.length, false, -1, nd);
291 }
292
293 static long read(FileDescriptor fd, ByteBuffer[] bufs, int offset, int length,
294 boolean directIO, int alignment, NativeDispatcher nd)
295 throws IOException
296 {
297 IOVecWrapper vec = IOVecWrapper.get(length);
298
299 boolean completed = false;
300 int iov_len = 0;
301 try {
302
303 // Iterate over buffers to populate native iovec array.
304 int count = offset + length;
305 int i = offset;
306 while (i < count && iov_len < IOV_MAX) {
307 ByteBuffer buf = bufs[i];
308 if (buf.isReadOnly())
309 throw new IllegalArgumentException("Read-only buffer");
310 int pos = buf.position();
311 int lim = buf.limit();
312 assert (pos <= lim);
313 int rem = (pos <= lim ? lim - pos : 0);
314
315 if (directIO && (rem % alignment != 0))
316 throw new IllegalArgumentException("IO size or position is not aligned");
317
318 if (rem > 0) {
319 vec.setBuffer(iov_len, buf, pos, rem);
320
321 // allocate shadow buffer to ensure I/O is done with direct buffer
322 if (!(buf instanceof DirectBuffer)) {
323 ByteBuffer shadow;
324 if (directIO) {
325 shadow = Util.getTemporaryAlignedDirectBuffer(rem, alignment);
326 } else {
327 shadow = Util.getTemporaryDirectBuffer(rem);
328 }
329 vec.setShadow(iov_len, shadow);
330 buf = shadow;
331 pos = shadow.position();
332 }
333
334 vec.putBase(iov_len, ((DirectBuffer)buf).address() + pos);
335 vec.putLen(iov_len, rem);
336 iov_len++;
337 }
338 i++;
339 }
340 if (iov_len == 0)
341 return 0L;
342
343 long bytesRead = nd.readv(fd, vec.address, iov_len);
344
345 // Notify the buffers how many bytes were read
346 long left = bytesRead;
347 for (int j=0; j<iov_len; j++) {
348 ByteBuffer shadow = vec.getShadow(j);
|