include/msgbuf.h

   1 /*
   2  * charybdis - an advanced ircd.
   3  * Copyright (c) 2016 William Pitcock <nenolod@dereferenced.org>.
   4  *
   5  * Permission to use, copy, modify, and/or distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice is present in all copies.
   8  *
   9  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  10  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  11  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  12  * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
  13  * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
  14  * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
  15  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  16  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
  17  * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
  18  * IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  19  * POSSIBILITY OF SUCH DAMAGE.
  20  */
  21
  22 #ifndef CHARYBDIS__MSGBUF_H
  23 #define CHARYBDIS__MSGBUF_H
  24
  25 #define MAXPARA         (15)
  26
  27 /* a key-value structure for each message tag. */
  28 struct MsgTag {
  29         const char *key;                /* the key of the tag (must be set) */
  30         const char *value;              /* the value of the tag or NULL */
  31         unsigned int capmask;           /* the capability mask this tag belongs to (used only when sending) */
  32 };
  33
  34 struct MsgBuf {
  35         size_t n_tags;                  /* the number of tags in the MsgBuf */
  36         struct MsgTag tags[MAXPARA];    /* the tags themselves, upto MAXPARA tags available */
  37
  38         const char *origin;             /* the origin of the message (or NULL) */
  39         const char *target;             /* the target of the message (either NULL, or custom defined) */
  40         const char *cmd;                /* the cmd/verb of the message (either NULL, or para[0]) */
  41
  42         size_t n_para;                  /* the number of parameters (always at least 1 if a full message) */
  43         const char *para[MAXPARA];      /* parameters vector (starting with cmd as para[0]) */
  44 };
  45
  46 struct MsgBuf_str_data {
  47         const struct MsgBuf *msgbuf;
  48         unsigned int caps;
  49 };
  50
  51 #define MSGBUF_CACHE_SIZE 32
  52
  53 struct MsgBuf_cache_entry {
  54         unsigned int caps;
  55         buf_head_t linebuf;
  56         struct MsgBuf_cache_entry *next;
  57 };
  58
  59 struct MsgBuf_cache {
  60         const struct MsgBuf *msgbuf;
  61         char message[DATALEN + 1];
  62         unsigned int overall_capmask;
  63
  64         /* Fixed maximum size linked list, new entries are allocated at the end
  65          * of the array but are accessed through the "next" pointers.
  66          *
  67          * This does not use rb dlink to avoid unnecessary individual allocations.
  68          */
  69         struct MsgBuf_cache_entry entry[MSGBUF_CACHE_SIZE];
  70         struct MsgBuf_cache_entry *head; /* LRU cache head */
  71 };
  72
  73 /*
  74  * parse a message into a MsgBuf.
  75  * returns 0 on success, 1 on error.
  76  */
  77 int msgbuf_parse(struct MsgBuf *msgbuf, char *line);
  78
  79 /*
  80  * unparse a pure MsgBuf into a buffer.
  81  * if origin is NULL, me.name will be used.
  82  * cmd may not be NULL.
  83  * returns 0 on success, 1 on error.
  84  */
  85 int msgbuf_unparse(char *buf, size_t buflen, const struct MsgBuf *msgbuf, unsigned int capmask);
  86
  87 /*
  88  * unparse a MsgBuf header plus payload into a buffer.
  89  * if origin is NULL, me.name will be used.
  90  * cmd may not be NULL.
  91  * returns 0 on success, 1 on error.
  92  */
  93 int msgbuf_unparse_fmt(char *buf, size_t buflen, const struct MsgBuf *head, unsigned int capmask, const char *fmt, ...) AFP(5, 6);
  94 int msgbuf_vunparse_fmt(char *buf, size_t buflen, const struct MsgBuf *head, unsigned int capmask, const char *fmt, va_list va);
  95
  96 int msgbuf_unparse_linebuf_tags(char *buf, size_t buflen, void *data);
  97 int msgbuf_unparse_prefix(char *buf, size_t *buflen, const struct MsgBuf *msgbuf, unsigned int capmask);
  98
  99 void msgbuf_cache_init(struct MsgBuf_cache *cache, const struct MsgBuf *msgbuf, const rb_strf_t *message);
 100 void msgbuf_cache_initf(struct MsgBuf_cache *cache, const struct MsgBuf *msgbuf, const rb_strf_t *message, const char *format, ...) AFP(4, 5);
 101 buf_head_t *msgbuf_cache_get(struct MsgBuf_cache *cache, unsigned int caps);
 102 void msgbuf_cache_free(struct MsgBuf_cache *cache);
 103
 104 static inline void
 105 msgbuf_init(struct MsgBuf *msgbuf)
 106 {
 107         memset(msgbuf, 0, sizeof(*msgbuf));
 108 }
 109
 110 static inline void
 111 msgbuf_append_tag(struct MsgBuf *msgbuf, const char *key, const char *value, unsigned int capmask)
 112 {
 113         if (msgbuf->n_tags < MAXPARA) {
 114                 msgbuf->tags[msgbuf->n_tags].key = key;
 115                 msgbuf->tags[msgbuf->n_tags].value = value;
 116                 msgbuf->tags[msgbuf->n_tags].capmask = capmask;
 117                 msgbuf->n_tags++;
 118         }
 119 }
 120
 121 #endif