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-rw-r--r--libevent-2.0.20-stable/event_tagging.c590
1 files changed, 590 insertions, 0 deletions
diff --git a/libevent-2.0.20-stable/event_tagging.c b/libevent-2.0.20-stable/event_tagging.c
new file mode 100644
index 0000000..a83e719
--- /dev/null
+++ b/libevent-2.0.20-stable/event_tagging.c
@@ -0,0 +1,590 @@
+/*
+ * Copyright (c) 2003-2009 Niels Provos <provos@citi.umich.edu>
+ * Copyright (c) 2009-2012 Niels Provos and Nick Mathewson
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "event2/event-config.h"
+
+#ifdef _EVENT_HAVE_SYS_TYPES_H
+#include <sys/types.h>
+#endif
+#ifdef _EVENT_HAVE_SYS_PARAM_H
+#include <sys/param.h>
+#endif
+
+#ifdef WIN32
+#define WIN32_LEAN_AND_MEAN
+#include <winsock2.h>
+#include <windows.h>
+#undef WIN32_LEAN_AND_MEAN
+#else
+#include <sys/ioctl.h>
+#endif
+
+#include <sys/queue.h>
+#ifdef _EVENT_HAVE_SYS_TIME_H
+#include <sys/time.h>
+#endif
+
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#ifndef WIN32
+#include <syslog.h>
+#endif
+#ifdef _EVENT_HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+#include <limits.h>
+
+#include "event2/event.h"
+#include "event2/tag.h"
+#include "event2/buffer.h"
+#include "log-internal.h"
+#include "mm-internal.h"
+#include "util-internal.h"
+
+/*
+ Here's our wire format:
+
+ Stream = TaggedData*
+
+ TaggedData = Tag Length Data
+ where the integer value of 'Length' is the length of 'data'.
+
+ Tag = HByte* LByte
+ where HByte is a byte with the high bit set, and LByte is a byte
+ with the high bit clear. The integer value of the tag is taken
+ by concatenating the lower 7 bits from all the tags. So for example,
+ the tag 0x66 is encoded as [66], whereas the tag 0x166 is encoded as
+ [82 66]
+
+ Length = Integer
+
+ Integer = NNibbles Nibble* Padding?
+ where NNibbles is a 4-bit value encoding the number of nibbles-1,
+ and each Nibble is 4 bits worth of encoded integer, in big-endian
+ order. If the total encoded integer size is an odd number of nibbles,
+ a final padding nibble with value 0 is appended.
+*/
+
+int evtag_decode_int(ev_uint32_t *pnumber, struct evbuffer *evbuf);
+int evtag_decode_int64(ev_uint64_t *pnumber, struct evbuffer *evbuf);
+int evtag_encode_tag(struct evbuffer *evbuf, ev_uint32_t tag);
+int evtag_decode_tag(ev_uint32_t *ptag, struct evbuffer *evbuf);
+
+void
+evtag_init(void)
+{
+}
+
+/*
+ * We encode integers by nibbles; the first nibble contains the number
+ * of significant nibbles - 1; this allows us to encode up to 64-bit
+ * integers. This function is byte-order independent.
+ *
+ * @param number a 32-bit unsigned integer to encode
+ * @param data a pointer to where the data should be written. Must
+ * have at least 5 bytes free.
+ * @return the number of bytes written into data.
+ */
+
+#define ENCODE_INT_INTERNAL(data, number) do { \
+ int off = 1, nibbles = 0; \
+ \
+ memset(data, 0, sizeof(number)+1); \
+ while (number) { \
+ if (off & 0x1) \
+ data[off/2] = (data[off/2] & 0xf0) | (number & 0x0f); \
+ else \
+ data[off/2] = (data[off/2] & 0x0f) | \
+ ((number & 0x0f) << 4); \
+ number >>= 4; \
+ off++; \
+ } \
+ \
+ if (off > 2) \
+ nibbles = off - 2; \
+ \
+ /* Off - 1 is the number of encoded nibbles */ \
+ data[0] = (data[0] & 0x0f) | ((nibbles & 0x0f) << 4); \
+ \
+ return ((off + 1) / 2); \
+} while (0)
+
+static inline int
+encode_int_internal(ev_uint8_t *data, ev_uint32_t number)
+{
+ ENCODE_INT_INTERNAL(data, number);
+}
+
+static inline int
+encode_int64_internal(ev_uint8_t *data, ev_uint64_t number)
+{
+ ENCODE_INT_INTERNAL(data, number);
+}
+
+void
+evtag_encode_int(struct evbuffer *evbuf, ev_uint32_t number)
+{
+ ev_uint8_t data[5];
+ int len = encode_int_internal(data, number);
+ evbuffer_add(evbuf, data, len);
+}
+
+void
+evtag_encode_int64(struct evbuffer *evbuf, ev_uint64_t number)
+{
+ ev_uint8_t data[9];
+ int len = encode_int64_internal(data, number);
+ evbuffer_add(evbuf, data, len);
+}
+
+/*
+ * Support variable length encoding of tags; we use the high bit in each
+ * octet as a continuation signal.
+ */
+
+int
+evtag_encode_tag(struct evbuffer *evbuf, ev_uint32_t tag)
+{
+ int bytes = 0;
+ ev_uint8_t data[5];
+
+ memset(data, 0, sizeof(data));
+ do {
+ ev_uint8_t lower = tag & 0x7f;
+ tag >>= 7;
+
+ if (tag)
+ lower |= 0x80;
+
+ data[bytes++] = lower;
+ } while (tag);
+
+ if (evbuf != NULL)
+ evbuffer_add(evbuf, data, bytes);
+
+ return (bytes);
+}
+
+static int
+decode_tag_internal(ev_uint32_t *ptag, struct evbuffer *evbuf, int dodrain)
+{
+ ev_uint32_t number = 0;
+ size_t len = evbuffer_get_length(evbuf);
+ ev_uint8_t *data;
+ size_t count = 0;
+ int shift = 0, done = 0;
+
+ /*
+ * the encoding of a number is at most one byte more than its
+ * storage size. however, it may also be much smaller.
+ */
+ data = evbuffer_pullup(
+ evbuf, len < sizeof(number) + 1 ? len : sizeof(number) + 1);
+
+ while (count++ < len) {
+ ev_uint8_t lower = *data++;
+ number |= (lower & 0x7f) << shift;
+ shift += 7;
+
+ if (!(lower & 0x80)) {
+ done = 1;
+ break;
+ }
+ }
+
+ if (!done)
+ return (-1);
+
+ if (dodrain)
+ evbuffer_drain(evbuf, count);
+
+ if (ptag != NULL)
+ *ptag = number;
+
+ return count > INT_MAX ? INT_MAX : (int)(count);
+}
+
+int
+evtag_decode_tag(ev_uint32_t *ptag, struct evbuffer *evbuf)
+{
+ return (decode_tag_internal(ptag, evbuf, 1 /* dodrain */));
+}
+
+/*
+ * Marshal a data type, the general format is as follows:
+ *
+ * tag number: one byte; length: var bytes; payload: var bytes
+ */
+
+void
+evtag_marshal(struct evbuffer *evbuf, ev_uint32_t tag,
+ const void *data, ev_uint32_t len)
+{
+ evtag_encode_tag(evbuf, tag);
+ evtag_encode_int(evbuf, len);
+ evbuffer_add(evbuf, (void *)data, len);
+}
+
+void
+evtag_marshal_buffer(struct evbuffer *evbuf, ev_uint32_t tag,
+ struct evbuffer *data)
+{
+ evtag_encode_tag(evbuf, tag);
+ /* XXX support more than UINT32_MAX data */
+ evtag_encode_int(evbuf, (ev_uint32_t)evbuffer_get_length(data));
+ evbuffer_add_buffer(evbuf, data);
+}
+
+/* Marshaling for integers */
+void
+evtag_marshal_int(struct evbuffer *evbuf, ev_uint32_t tag, ev_uint32_t integer)
+{
+ ev_uint8_t data[5];
+ int len = encode_int_internal(data, integer);
+
+ evtag_encode_tag(evbuf, tag);
+ evtag_encode_int(evbuf, len);
+ evbuffer_add(evbuf, data, len);
+}
+
+void
+evtag_marshal_int64(struct evbuffer *evbuf, ev_uint32_t tag,
+ ev_uint64_t integer)
+{
+ ev_uint8_t data[9];
+ int len = encode_int64_internal(data, integer);
+
+ evtag_encode_tag(evbuf, tag);
+ evtag_encode_int(evbuf, len);
+ evbuffer_add(evbuf, data, len);
+}
+
+void
+evtag_marshal_string(struct evbuffer *buf, ev_uint32_t tag, const char *string)
+{
+ /* TODO support strings longer than UINT32_MAX ? */
+ evtag_marshal(buf, tag, string, (ev_uint32_t)strlen(string));
+}
+
+void
+evtag_marshal_timeval(struct evbuffer *evbuf, ev_uint32_t tag, struct timeval *tv)
+{
+ ev_uint8_t data[10];
+ int len = encode_int_internal(data, tv->tv_sec);
+ len += encode_int_internal(data + len, tv->tv_usec);
+ evtag_marshal(evbuf, tag, data, len);
+}
+
+#define DECODE_INT_INTERNAL(number, maxnibbles, pnumber, evbuf, offset) \
+do { \
+ ev_uint8_t *data; \
+ ev_ssize_t len = evbuffer_get_length(evbuf) - offset; \
+ int nibbles = 0; \
+ \
+ if (len <= 0) \
+ return (-1); \
+ \
+ /* XXX(niels): faster? */ \
+ data = evbuffer_pullup(evbuf, offset + 1) + offset; \
+ \
+ nibbles = ((data[0] & 0xf0) >> 4) + 1; \
+ if (nibbles > maxnibbles || (nibbles >> 1) + 1 > len) \
+ return (-1); \
+ len = (nibbles >> 1) + 1; \
+ \
+ data = evbuffer_pullup(evbuf, offset + len) + offset; \
+ \
+ while (nibbles > 0) { \
+ number <<= 4; \
+ if (nibbles & 0x1) \
+ number |= data[nibbles >> 1] & 0x0f; \
+ else \
+ number |= (data[nibbles >> 1] & 0xf0) >> 4; \
+ nibbles--; \
+ } \
+ \
+ *pnumber = number; \
+ \
+ return (int)(len); \
+} while (0)
+
+/* Internal: decode an integer from an evbuffer, without draining it.
+ * Only integers up to 32-bits are supported.
+ *
+ * @param evbuf the buffer to read from
+ * @param offset an index into the buffer at which we should start reading.
+ * @param pnumber a pointer to receive the integer.
+ * @return The length of the number as encoded, or -1 on error.
+ */
+
+static int
+decode_int_internal(ev_uint32_t *pnumber, struct evbuffer *evbuf, int offset)
+{
+ ev_uint32_t number = 0;
+ DECODE_INT_INTERNAL(number, 8, pnumber, evbuf, offset);
+}
+
+static int
+decode_int64_internal(ev_uint64_t *pnumber, struct evbuffer *evbuf, int offset)
+{
+ ev_uint64_t number = 0;
+ DECODE_INT_INTERNAL(number, 16, pnumber, evbuf, offset);
+}
+
+int
+evtag_decode_int(ev_uint32_t *pnumber, struct evbuffer *evbuf)
+{
+ int res = decode_int_internal(pnumber, evbuf, 0);
+ if (res != -1)
+ evbuffer_drain(evbuf, res);
+
+ return (res == -1 ? -1 : 0);
+}
+
+int
+evtag_decode_int64(ev_uint64_t *pnumber, struct evbuffer *evbuf)
+{
+ int res = decode_int64_internal(pnumber, evbuf, 0);
+ if (res != -1)
+ evbuffer_drain(evbuf, res);
+
+ return (res == -1 ? -1 : 0);
+}
+
+int
+evtag_peek(struct evbuffer *evbuf, ev_uint32_t *ptag)
+{
+ return (decode_tag_internal(ptag, evbuf, 0 /* dodrain */));
+}
+
+int
+evtag_peek_length(struct evbuffer *evbuf, ev_uint32_t *plength)
+{
+ int res, len;
+
+ len = decode_tag_internal(NULL, evbuf, 0 /* dodrain */);
+ if (len == -1)
+ return (-1);
+
+ res = decode_int_internal(plength, evbuf, len);
+ if (res == -1)
+ return (-1);
+
+ *plength += res + len;
+
+ return (0);
+}
+
+int
+evtag_payload_length(struct evbuffer *evbuf, ev_uint32_t *plength)
+{
+ int res, len;
+
+ len = decode_tag_internal(NULL, evbuf, 0 /* dodrain */);
+ if (len == -1)
+ return (-1);
+
+ res = decode_int_internal(plength, evbuf, len);
+ if (res == -1)
+ return (-1);
+
+ return (0);
+}
+
+/* just unmarshals the header and returns the length of the remaining data */
+
+int
+evtag_unmarshal_header(struct evbuffer *evbuf, ev_uint32_t *ptag)
+{
+ ev_uint32_t len;
+
+ if (decode_tag_internal(ptag, evbuf, 1 /* dodrain */) == -1)
+ return (-1);
+ if (evtag_decode_int(&len, evbuf) == -1)
+ return (-1);
+
+ if (evbuffer_get_length(evbuf) < len)
+ return (-1);
+
+ return (len);
+}
+
+int
+evtag_consume(struct evbuffer *evbuf)
+{
+ int len;
+ if ((len = evtag_unmarshal_header(evbuf, NULL)) == -1)
+ return (-1);
+ evbuffer_drain(evbuf, len);
+
+ return (0);
+}
+
+/* Reads the data type from an event buffer */
+
+int
+evtag_unmarshal(struct evbuffer *src, ev_uint32_t *ptag, struct evbuffer *dst)
+{
+ int len;
+
+ if ((len = evtag_unmarshal_header(src, ptag)) == -1)
+ return (-1);
+
+ if (evbuffer_add(dst, evbuffer_pullup(src, len), len) == -1)
+ return (-1);
+
+ evbuffer_drain(src, len);
+
+ return (len);
+}
+
+/* Marshaling for integers */
+
+int
+evtag_unmarshal_int(struct evbuffer *evbuf, ev_uint32_t need_tag,
+ ev_uint32_t *pinteger)
+{
+ ev_uint32_t tag;
+ ev_uint32_t len;
+ int result;
+
+ if (decode_tag_internal(&tag, evbuf, 1 /* dodrain */) == -1)
+ return (-1);
+ if (need_tag != tag)
+ return (-1);
+ if (evtag_decode_int(&len, evbuf) == -1)
+ return (-1);
+
+ if (evbuffer_get_length(evbuf) < len)
+ return (-1);
+
+ result = decode_int_internal(pinteger, evbuf, 0);
+ evbuffer_drain(evbuf, len);
+ if (result < 0 || (size_t)result > len) /* XXX Should this be != rather than > ?*/
+ return (-1);
+ else
+ return result;
+}
+
+int
+evtag_unmarshal_int64(struct evbuffer *evbuf, ev_uint32_t need_tag,
+ ev_uint64_t *pinteger)
+{
+ ev_uint32_t tag;
+ ev_uint32_t len;
+ int result;
+
+ if (decode_tag_internal(&tag, evbuf, 1 /* dodrain */) == -1)
+ return (-1);
+ if (need_tag != tag)
+ return (-1);
+ if (evtag_decode_int(&len, evbuf) == -1)
+ return (-1);
+
+ if (evbuffer_get_length(evbuf) < len)
+ return (-1);
+
+ result = decode_int64_internal(pinteger, evbuf, 0);
+ evbuffer_drain(evbuf, len);
+ if (result < 0 || (size_t)result > len) /* XXX Should this be != rather than > ?*/
+ return (-1);
+ else
+ return result;
+}
+
+/* Unmarshal a fixed length tag */
+
+int
+evtag_unmarshal_fixed(struct evbuffer *src, ev_uint32_t need_tag, void *data,
+ size_t len)
+{
+ ev_uint32_t tag;
+ int tag_len;
+
+ /* Now unmarshal a tag and check that it matches the tag we want */
+ if ((tag_len = evtag_unmarshal_header(src, &tag)) < 0 ||
+ tag != need_tag)
+ return (-1);
+
+ if ((size_t)tag_len != len)
+ return (-1);
+
+ evbuffer_remove(src, data, len);
+ return (0);
+}
+
+int
+evtag_unmarshal_string(struct evbuffer *evbuf, ev_uint32_t need_tag,
+ char **pstring)
+{
+ ev_uint32_t tag;
+ int tag_len;
+
+ if ((tag_len = evtag_unmarshal_header(evbuf, &tag)) == -1 ||
+ tag != need_tag)
+ return (-1);
+
+ *pstring = mm_malloc(tag_len + 1);
+ if (*pstring == NULL) {
+ event_warn("%s: malloc", __func__);
+ return -1;
+ }
+ evbuffer_remove(evbuf, *pstring, tag_len);
+ (*pstring)[tag_len] = '\0';
+
+ return (0);
+}
+
+int
+evtag_unmarshal_timeval(struct evbuffer *evbuf, ev_uint32_t need_tag,
+ struct timeval *ptv)
+{
+ ev_uint32_t tag;
+ ev_uint32_t integer;
+ int len, offset, offset2;
+ int result = -1;
+
+ if ((len = evtag_unmarshal_header(evbuf, &tag)) == -1)
+ return (-1);
+ if (tag != need_tag)
+ goto done;
+ if ((offset = decode_int_internal(&integer, evbuf, 0)) == -1)
+ goto done;
+ ptv->tv_sec = integer;
+ if ((offset2 = decode_int_internal(&integer, evbuf, offset)) == -1)
+ goto done;
+ ptv->tv_usec = integer;
+ if (offset + offset2 > len) /* XXX Should this be != instead of > ? */
+ goto done;
+
+ result = 0;
+ done:
+ evbuffer_drain(evbuf, len);
+ return result;
+}