mdw@git.distorted.org.uk Git - secnet/blob - util.h

   1 #ifndef util_h
   2 #define util_h
   3
   4 #include "secnet.h"
   5 #include <gmp.h>
   6
   7 #include "hackypar.h"
   8
   9 #define BUF_ASSERT_FREE(buf) do { buffer_assert_free((buf), \
  10                                                      __FILE__,__LINE__); } \
  11 while(0)
  12 #define BUF_ASSERT_USED(buf) do { buffer_assert_used((buf), \
  13                                                      __FILE__,__LINE__); } \
  14 while(0)
  15 #define BUF_ALLOC(buf,own) do { buffer_assert_free((buf),__FILE__,__LINE__); \
  16          (buf)->free=False; (buf)->owner=(own); (buf)->start=(buf)->base; \
  17          (buf)->size=0; } while(0)
  18 #define BUF_FREE(buf) do { (buf)->free=True; } while(0)
  19
  20 extern void buffer_assert_free(struct buffer_if *buffer, cstring_t file,
  21                                int line);
  22 extern void buffer_assert_used(struct buffer_if *buffer, cstring_t file,
  23                                int line);
  24 extern void buffer_new(struct buffer_if *buffer, int32_t len);
  25 extern void buffer_init(struct buffer_if *buffer, int32_t max_start_pad);
  26 extern void buffer_copy(struct buffer_if *dst, const struct buffer_if *src);
  27 extern void *buf_append(struct buffer_if *buf, int32_t amount);
  28 extern void *buf_prepend(struct buffer_if *buf, int32_t amount);
  29 extern void *buf_unappend(struct buffer_if *buf, int32_t amount);
  30 extern void *buf_unprepend(struct buffer_if *buf, int32_t amount);
  31
  32 /*
  33  * void BUF_ADD_BYTES(append,    struct buffer_if*, const void*, int32_t size);
  34  * void BUF_ADD_BYTES(prepend,   struct buffer_if*, const void*, int32_t size);
  35  * void BUF_GET_BYTES(unappend,  struct buffer_if*,       void*, int32_t size);
  36  * void BUF_GET_BYTES(unprepend, struct buffer_if*,       void*, int32_t size);
  37  *     // all of these evaluate size twice
  38  *
  39  * void BUF_ADD_OBJ(append,    struct_buffer_if*, const OBJECT& something);
  40  * void BUF_ADD_OBJ(prepend,   struct_buffer_if*, const OBJECT& something);
  41  * void BUF_GET_OBJ(unappend,  struct_buffer_if*,       OBJECT& something);
  42  * void BUF_GET_OBJ(unprepend, struct_buffer_if*,       OBJECT& something);
  43  */
  44 #define BUF_ADD_BYTES(appendprepend, bufp, datap, size)                 \
  45     (buf_un##appendprepend /* ensures we have correct direction */,     \
  46      memcpy(buf_##appendprepend((bufp),(size)),(datap),(size)))
  47 #define BUF_ADD_OBJ(appendprepend, bufp, obj) \
  48     BUF_ADD_BYTES(appendprepend,(bufp),&(obj),sizeof((obj)))
  49 #define BUF_GET_BYTES(unappendunprepend, bufp, datap, size)             \
  50     (BUF_GET__DOESNOTEXIST__buf_un##unappendunprepend,                  \
  51      memcpy((datap),buf_##unappendunprepend((bufp),(size)),(size)))
  52 #define BUF_GET_OBJ(unappendunprepend, bufp, obj) \
  53     BUF_ADD_BYTES(unappendunprepend,&(obj),(bufp),sizeof((obj)))
  54 #define BUF_GET__DOESNOTEXIST__buf_ununappend  0
  55 #define BUF_GET__DOESNOTEXIST__buf_ununprepend 0
  56
  57 static inline int32_t buf_remaining_space(const struct buffer_if *buf)
  58 {
  59     return (buf->base + buf->alloclen) - (buf->start + buf->size);
  60 }
  61
  62 extern void buffer_readonly_view(struct buffer_if *n, const void*, int32_t len);
  63 extern void buffer_readonly_clone(struct buffer_if *n, const struct buffer_if*);
  64   /* Caller must only use unappend, unprepend et al. on n.
  65    * New buffer state (in n) before this can be undefined.  After use,
  66    * it must NOT be freed. */
  67
  68 extern void buf_append_string(struct buffer_if *buf, cstring_t s);
  69
  70 extern void read_mpbin(MP_INT *a, uint8_t *bin, int binsize);
  71
  72 extern char *write_mpstring(MP_INT *a);
  73
  74 extern int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen);
  75
  76 extern struct log_if *init_log(list_t *loglist);
  77
  78 extern void send_nak(const struct comm_addr *dest, uint32_t our_index,
  79                      uint32_t their_index, uint32_t msgtype,
  80                      struct buffer_if *buf, const char *logwhy);
  81
  82 extern int consttime_memeq(const void *s1, const void *s2, size_t n);
  83
  84 const char *iaddr_to_string(const union iaddr *ia);
  85 int iaddr_socklen(const union iaddr *ia);
  86
  87 void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia,
  88                           const char *desc);
  89
  90
  91 /*----- line-buffered asynch input -----*/
  92
  93 enum async_linebuf_result {
  94     async_linebuf_nothing,
  95     async_linebuf_ok,
  96     async_linebuf_eof,
  97     async_linebuf_broken,
  98 };
  99
 100 enum async_linebuf_result
 101 async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf,
 102                    const char **emsg_out);
 103    /* Implements reading whole lines, asynchronously.  Use like
 104     * this:
 105     *   - set up the fd, which should be readable, O_NONBLOCK
 106     *   - set up and initialise buffer, which should be big enough
 107     *     for one line plus its trailing newline, and be empty
 108     *     with start==base
 109     *   - in your beforepoll_fn, be interested in POLLIN
 110     *   - in your afterpoll_fn, repeatedly call this function
 111     *     until it doesn't return `nothing'
 112     *   - after you're done, simply close fd and free or reset buf
 113     * State on return from async_linebuf_read depends on return value:
 114     *
 115     *   async_linebuf_nothing:
 116     *
 117     *      No complete lines available right now.  You should return
 118     *      from afterpoll.  buf should be left untouched until the
 119     *      next call to async_linebuf_read.
 120     *
 121     *   async_linebuf_ok:
 122     *
 123     *      buf->base contains a input line as a nul-terminated string
 124     *      (\n replaced by \0); *emsg_out==0.  You must call
 125     *      async_linebuf_read again before returning from afterpoll.
 126     *
 127     *   async_linebuf_eof:
 128     *
 129     *      EOF on stream.  buf->base contains any partial
 130     *      (non-newline-terminated) line; *emsg_out!=0 iff there was
 131     *      such a partial line.  You can call async_linebuf_read again
 132     *      if you like but it will probably just return eof again.
 133     *
 134     *   broken:
 135     *
 136     *      Fatal problem (might be overly long lines, nuls in input
 137     *      data, bad bits in pfd->revents, errors from read, etc.)
 138     *
 139     *      *emsg_out is the error message describing the problem;
 140     *      this message might be stored in buf, might be from
 141     *      strerror, or might be a constant.
 142     *
 143     *      You must not call async_linebuf_read again.  buf contents
 144     *      is undefined: it is only safe to reset or free.
 145     *
 146     * While using this function, do not look at buf->start or ->size
 147     * or anything after the first '\0' in buf.
 148     *
 149     * If you decide to stop reading with async_linebuf_read that's
 150     * fine and you can reset or free buf, but you risk missing some
 151     * read-but-not-reported data.
 152     */
 153
 154 /*----- some handy macros -----*/
 155
 156 #define MINMAX(ae,be,op) ({                     \
 157         typeof((ae)) a=(ae);                    \
 158         typeof((be)) b=(be);                    \
 159         a op b ? a : b;                         \
 160     })
 161 #define MAX(a,b) MINMAX((a),(b),>)
 162 #define MIN(a,b) MINMAX((a),(b),<)
 163
 164 #define MAX_RAW(a,b) ((a)>(b)?(a):(b))
 165 #define MIN_RAW(a,b) ((a)<(b)?(a):(b))
 166
 167 static inline bool_t iswouldblock(int e)
 168     { return e==EWOULDBLOCK || e==EAGAIN; }
 169
 170 #endif /* util_h */