include/msgbuf.h

   1 /*
   2  * solanum - an advanced ircd.
   3  * Copyright (c) 2016 Ariadne Conill <ariadne@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 SOLANUM__MSGBUF_H
  23 #define SOLANUM__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         char *endp;                     /* one past the end of the original array */
  42
  43         size_t n_para;                  /* the number of parameters (always at least 1 if a full message) */
  44         const char *para[MAXPARA];      /* parameters vector (starting with cmd as para[0]) */
  45 };
  46
  47 struct MsgBuf_str_data {
  48         const struct MsgBuf *msgbuf;
  49         unsigned int caps;
  50 };
  51
  52 #define MSGBUF_CACHE_SIZE 32
  53
  54 struct MsgBuf_cache_entry {
  55         unsigned int caps;
  56         buf_head_t linebuf;
  57         struct MsgBuf_cache_entry *next;
  58 };
  59
  60 struct MsgBuf_cache {
  61         const struct MsgBuf *msgbuf;
  62         char message[DATALEN + 1];
  63         unsigned int overall_capmask;
  64
  65         /* Fixed maximum size linked list, new entries are allocated at the end
  66          * of the array but are accessed through the "next" pointers.
  67          *
  68          * This does not use rb dlink to avoid unnecessary individual allocations.
  69          */
  70         struct MsgBuf_cache_entry entry[MSGBUF_CACHE_SIZE];
  71         struct MsgBuf_cache_entry *head; /* LRU cache head */
  72 };
  73
  74 /*
  75  * parse a message into a MsgBuf.
  76  * returns 0 on success, 1 on error.
  77  */
  78 int msgbuf_parse(struct MsgBuf *msgbuf, char *line);
  79
  80 /*
  81  * Unparse the tail of a msgbuf perfectly, preserving framing details
  82  * msgbuf->para[n] will reach to the end of the line
  83  */
  84 void msgbuf_reconstruct_tail(struct MsgBuf *msgbuf, size_t n);
  85
  86 /*
  87  * unparse a pure MsgBuf into a buffer.
  88  * if origin is NULL, me.name will be used.
  89  * cmd may not be NULL.
  90  * returns 0 on success, 1 on error.
  91  */
  92 int msgbuf_unparse(char *buf, size_t buflen, const struct MsgBuf *msgbuf, unsigned int capmask);
  93
  94 /*
  95  * unparse a MsgBuf header plus payload into a buffer.
  96  * if origin is NULL, me.name will be used.
  97  * cmd may not be NULL.
  98  * returns 0 on success, 1 on error.
  99  */
 100 int msgbuf_unparse_fmt(char *buf, size_t buflen, const struct MsgBuf *head, unsigned int capmask, const char *fmt, ...) AFP(5, 6);
 101 int msgbuf_vunparse_fmt(char *buf, size_t buflen, const struct MsgBuf *head, unsigned int capmask, const char *fmt, va_list va);
 102
 103 int msgbuf_unparse_linebuf_tags(char *buf, size_t buflen, void *data);
 104 int msgbuf_unparse_prefix(char *buf, size_t *buflen, const struct MsgBuf *msgbuf, unsigned int capmask);
 105
 106 void msgbuf_cache_init(struct MsgBuf_cache *cache, const struct MsgBuf *msgbuf, const rb_strf_t *message);
 107 void msgbuf_cache_initf(struct MsgBuf_cache *cache, const struct MsgBuf *msgbuf, const rb_strf_t *message, const char *format, ...) AFP(4, 5);
 108 buf_head_t *msgbuf_cache_get(struct MsgBuf_cache *cache, unsigned int caps);
 109 void msgbuf_cache_free(struct MsgBuf_cache *cache);
 110
 111 static inline void
 112 msgbuf_init(struct MsgBuf *msgbuf)
 113 {
 114         memset(msgbuf, 0, sizeof(*msgbuf));
 115 }
 116
 117 static inline void
 118 msgbuf_append_tag(struct MsgBuf *msgbuf, const char *key, const char *value, unsigned int capmask)
 119 {
 120         if (msgbuf->n_tags < MAXPARA) {
 121                 msgbuf->tags[msgbuf->n_tags].key = key;
 122                 msgbuf->tags[msgbuf->n_tags].value = value;
 123                 msgbuf->tags[msgbuf->n_tags].capmask = capmask;
 124                 msgbuf->n_tags++;
 125         }
 126 }
 127
 128 #endif