auto import from //depot/cupcake/@135843
diff --git a/libcutils/record_stream.c b/libcutils/record_stream.c
new file mode 100644
index 0000000..274423b
--- /dev/null
+++ b/libcutils/record_stream.c
@@ -0,0 +1,186 @@
+/* libs/cutils/record_stream.c
+**
+** Copyright 2006, The Android Open Source Project
+**
+** 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 <stdlib.h>
+#include <unistd.h>
+#include <assert.h>
+#include <errno.h>
+#include <cutils/record_stream.h>
+#include <string.h>
+#include <stdint.h>
+#ifdef HAVE_WINSOCK
+#include <winsock2.h> /* for ntohl */
+#else
+#include <netinet/in.h>
+#endif
+
+#define HEADER_SIZE 4
+
+struct RecordStream {
+ int fd;
+ size_t maxRecordLen;
+
+ unsigned char *buffer;
+
+ unsigned char *unconsumed;
+ unsigned char *read_end;
+ unsigned char *buffer_end;
+};
+
+
+extern RecordStream *record_stream_new(int fd, size_t maxRecordLen)
+{
+ RecordStream *ret;
+
+ assert (maxRecordLen <= 0xffff);
+
+ ret = (RecordStream *)calloc(1, sizeof(RecordStream));
+
+ ret->fd = fd;
+ ret->maxRecordLen = maxRecordLen;
+ ret->buffer = (unsigned char *)malloc (maxRecordLen + HEADER_SIZE);
+
+ ret->unconsumed = ret->buffer;
+ ret->read_end = ret->buffer;
+ ret->buffer_end = ret->buffer + maxRecordLen + HEADER_SIZE;
+
+ return ret;
+}
+
+
+extern void record_stream_free(RecordStream *rs)
+{
+ free(rs->buffer);
+ free(rs);
+}
+
+
+/* returns NULL; if there isn't a full record in the buffer */
+static unsigned char * getEndOfRecord (unsigned char *p_begin,
+ unsigned char *p_end)
+{
+ size_t len;
+ unsigned char * p_ret;
+
+ if (p_end < p_begin + HEADER_SIZE) {
+ return NULL;
+ }
+
+ //First four bytes are length
+ len = ntohl(*((uint32_t *)p_begin));
+
+ p_ret = p_begin + HEADER_SIZE + len;
+
+ if (p_end < p_ret) {
+ return NULL;
+ }
+
+ return p_ret;
+}
+
+static void *getNextRecord (RecordStream *p_rs, size_t *p_outRecordLen)
+{
+ unsigned char *record_start, *record_end;
+
+ record_end = getEndOfRecord (p_rs->unconsumed, p_rs->read_end);
+
+ if (record_end != NULL) {
+ /* one full line in the buffer */
+ record_start = p_rs->unconsumed + HEADER_SIZE;
+ p_rs->unconsumed = record_end;
+
+ *p_outRecordLen = record_end - record_start;
+
+ return record_start;
+ }
+
+ return NULL;
+}
+
+/**
+ * Reads the next record from stream fd
+ * Records are prefixed by a 16-bit big endian length value
+ * Records may not be larger than maxRecordLen
+ *
+ * Doesn't guard against EINTR
+ *
+ * p_outRecord and p_outRecordLen may not be NULL
+ *
+ * Return 0 on success, -1 on fail
+ * Returns 0 with *p_outRecord set to NULL on end of stream
+ * Returns -1 / errno = EAGAIN if it needs to read again
+ */
+int record_stream_get_next (RecordStream *p_rs, void ** p_outRecord,
+ size_t *p_outRecordLen)
+{
+ void *ret;
+
+ ssize_t countRead;
+
+ /* is there one record already in the buffer? */
+ ret = getNextRecord (p_rs, p_outRecordLen);
+
+ if (ret != NULL) {
+ *p_outRecord = ret;
+ return 0;
+ }
+
+ // if the buffer is full and we don't have a full record
+ if (p_rs->unconsumed == p_rs->buffer
+ && p_rs->read_end == p_rs->buffer_end
+ ) {
+ // this should never happen
+ //LOGE("max record length exceeded\n");
+ assert (0);
+ errno = EFBIG;
+ return -1;
+ }
+
+ if (p_rs->unconsumed != p_rs->buffer) {
+ // move remainder to the beginning of the buffer
+ size_t toMove;
+
+ toMove = p_rs->read_end - p_rs->unconsumed;
+ if (toMove) {
+ memmove(p_rs->buffer, p_rs->unconsumed, toMove);
+ }
+
+ p_rs->read_end = p_rs->buffer + toMove;
+ p_rs->unconsumed = p_rs->buffer;
+ }
+
+ countRead = read (p_rs->fd, p_rs->read_end, p_rs->buffer_end - p_rs->read_end);
+
+ if (countRead <= 0) {
+ /* note: end-of-stream drops through here too */
+ *p_outRecord = NULL;
+ return countRead;
+ }
+
+ p_rs->read_end += countRead;
+
+ ret = getNextRecord (p_rs, p_outRecordLen);
+
+ if (ret == NULL) {
+ /* not enough of a buffer to for a whole command */
+ errno = EAGAIN;
+ return -1;
+ }
+
+ *p_outRecord = ret;
+ return 0;
+}