1 /* 2 * Copyright (c) 2000-2007 Niels Provos <provos (at) citi.umich.edu> 3 * Copyright (c) 2007-2012 Niels Provos and Nick Mathewson 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. The name of the author may not be used to endorse or promote products 14 * derived from this software without specific prior written permission. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 26 */ 27 #ifndef _EVENT2_TAG_H_ 28 #define _EVENT2_TAG_H_ 29 30 /** @file event2/tag.h 31 32 Helper functions for reading and writing tagged data onto buffers. 33 34 */ 35 36 #ifdef __cplusplus 37 extern "C" { 38 #endif 39 40 #include <event2/event-config.h> 41 #ifdef _EVENT_HAVE_SYS_TYPES_H 42 #include <sys/types.h> 43 #endif 44 #ifdef _EVENT_HAVE_SYS_TIME_H 45 #include <sys/time.h> 46 #endif 47 48 /* For int types. */ 49 #include <event2/util.h> 50 51 struct evbuffer; 52 53 /* 54 * Marshaling tagged data - We assume that all tags are inserted in their 55 * numeric order - so that unknown tags will always be higher than the 56 * known ones - and we can just ignore the end of an event buffer. 57 */ 58 59 void evtag_init(void); 60 61 /** 62 Unmarshals the header and returns the length of the payload 63 64 @param evbuf the buffer from which to unmarshal data 65 @param ptag a pointer in which the tag id is being stored 66 @returns -1 on failure or the number of bytes in the remaining payload. 67 */ 68 int evtag_unmarshal_header(struct evbuffer *evbuf, ev_uint32_t *ptag); 69 70 void evtag_marshal(struct evbuffer *evbuf, ev_uint32_t tag, const void *data, 71 ev_uint32_t len); 72 void evtag_marshal_buffer(struct evbuffer *evbuf, ev_uint32_t tag, 73 struct evbuffer *data); 74 75 /** 76 Encode an integer and store it in an evbuffer. 77 78 We encode integers by nybbles; the first nibble contains the number 79 of significant nibbles - 1; this allows us to encode up to 64-bit 80 integers. This function is byte-order independent. 81 82 @param evbuf evbuffer to store the encoded number 83 @param number a 32-bit integer 84 */ 85 void evtag_encode_int(struct evbuffer *evbuf, ev_uint32_t number); 86 void evtag_encode_int64(struct evbuffer *evbuf, ev_uint64_t number); 87 88 void evtag_marshal_int(struct evbuffer *evbuf, ev_uint32_t tag, 89 ev_uint32_t integer); 90 void evtag_marshal_int64(struct evbuffer *evbuf, ev_uint32_t tag, 91 ev_uint64_t integer); 92 93 void evtag_marshal_string(struct evbuffer *buf, ev_uint32_t tag, 94 const char *string); 95 96 void evtag_marshal_timeval(struct evbuffer *evbuf, ev_uint32_t tag, 97 struct timeval *tv); 98 99 int evtag_unmarshal(struct evbuffer *src, ev_uint32_t *ptag, 100 struct evbuffer *dst); 101 int evtag_peek(struct evbuffer *evbuf, ev_uint32_t *ptag); 102 int evtag_peek_length(struct evbuffer *evbuf, ev_uint32_t *plength); 103 int evtag_payload_length(struct evbuffer *evbuf, ev_uint32_t *plength); 104 int evtag_consume(struct evbuffer *evbuf); 105 106 int evtag_unmarshal_int(struct evbuffer *evbuf, ev_uint32_t need_tag, 107 ev_uint32_t *pinteger); 108 int evtag_unmarshal_int64(struct evbuffer *evbuf, ev_uint32_t need_tag, 109 ev_uint64_t *pinteger); 110 111 int evtag_unmarshal_fixed(struct evbuffer *src, ev_uint32_t need_tag, 112 void *data, size_t len); 113 114 int evtag_unmarshal_string(struct evbuffer *evbuf, ev_uint32_t need_tag, 115 char **pstring); 116 117 int evtag_unmarshal_timeval(struct evbuffer *evbuf, ev_uint32_t need_tag, 118 struct timeval *ptv); 119 120 #ifdef __cplusplus 121 } 122 #endif 123 124 #endif /* _EVENT2_TAG_H_ */ 125
