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_destroy(struct buffer_if *buffer);
  27 extern void buffer_copy(struct buffer_if *dst, const struct buffer_if *src);
  28 extern void *buf_append(struct buffer_if *buf, int32_t amount);
  29 extern void *buf_prepend(struct buffer_if *buf, int32_t amount);
  30 extern void *buf_unappend(struct buffer_if *buf, int32_t amount);
  31 extern void *buf_unprepend(struct buffer_if *buf, int32_t amount);
  32
  33 /*
  34  * void BUF_ADD_BYTES(append,    struct buffer_if*, const void*, int32_t size);
  35  * void BUF_ADD_BYTES(prepend,   struct buffer_if*, const void*, int32_t size);
  36  * void BUF_GET_BYTES(unappend,  struct buffer_if*,       void*, int32_t size);
  37  * void BUF_GET_BYTES(unprepend, struct buffer_if*,       void*, int32_t size);
  38  *     // all of these evaluate size twice
  39  *
  40  * void BUF_ADD_OBJ(append,    struct_buffer_if*, const OBJECT& something);
  41  * void BUF_ADD_OBJ(prepend,   struct_buffer_if*, const OBJECT& something);
  42  * void BUF_GET_OBJ(unappend,  struct_buffer_if*,       OBJECT& something);
  43  * void BUF_GET_OBJ(unprepend, struct_buffer_if*,       OBJECT& something);
  44  */
  45 #define BUF_ADD_BYTES(appendprepend, bufp, datap, size)                 \
  46     (buf_un##appendprepend /* ensures we have correct direction */,     \
  47      memcpy(buf_##appendprepend((bufp),(size)),(datap),(size)))
  48 #define BUF_ADD_OBJ(appendprepend, bufp, obj) \
  49     BUF_ADD_BYTES(appendprepend,(bufp),&(obj),sizeof((obj)))
  50 #define BUF_GET_BYTES(unappendunprepend, bufp, datap, size)             \
  51     (BUF_GET__DOESNOTEXIST__buf_un##unappendunprepend,                  \
  52      memcpy((datap),buf_##unappendunprepend((bufp),(size)),(size)))
  53 #define BUF_GET_OBJ(unappendunprepend, bufp, obj) \
  54     BUF_ADD_BYTES(unappendunprepend,&(obj),(bufp),sizeof((obj)))
  55 #define BUF_GET__DOESNOTEXIST__buf_ununappend  0
  56 #define BUF_GET__DOESNOTEXIST__buf_ununprepend 0
  57
  58 static inline int32_t buf_remaining_space(const struct buffer_if *buf)
  59 {
  60     return (buf->base + buf->alloclen) - (buf->start + buf->size);
  61 }
  62
  63 extern void buffer_readonly_view(struct buffer_if *n, const void*, int32_t len);
  64 extern void buffer_readonly_clone(struct buffer_if *n, const struct buffer_if*);
  65   /* Caller must only use unappend, unprepend et al. on n.
  66    * New buffer state (in n) before this can be undefined.  After use,
  67    * it must NOT be freed. */
  68
  69 extern void buf_append_string(struct buffer_if *buf, cstring_t s);
  70
  71 extern void read_mpbin(MP_INT *a, uint8_t *bin, int binsize);
  72
  73 extern char *write_mpstring(MP_INT *a);
  74
  75 extern int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen);
  76
  77 extern struct log_if *init_log(list_t *loglist);
  78
  79 extern void send_nak(const struct comm_addr *dest, uint32_t our_index,
  80                      uint32_t their_index, uint32_t msgtype,
  81                      struct buffer_if *buf, const char *logwhy);
  82
  83 extern int consttime_memeq(const void *s1, const void *s2, size_t n);
  84
  85 const char *iaddr_to_string(const union iaddr *ia);
  86 int iaddr_socklen(const union iaddr *ia);
  87
  88 void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia,
  89                           const char *desc);
  90
  91
  92 #define SBUF (bufs[b]) /* temporary macro */
  93
  94 /*----- line-buffered asynch input -----*/
  95
  96 enum async_linebuf_result {
  97     async_linebuf_nothing,
  98     async_linebuf_ok,
  99     async_linebuf_eof,
 100     async_linebuf_broken,
 101 };
 102
 103 const char *pollbadbit(int revents); /* returns 0, or bad bit description */
 104
 105 enum async_linebuf_result
 106 async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf,
 107                    const char **emsg_out);
 108    /* Implements reading whole lines, asynchronously.  Use like
 109     * this:
 110     *   - set up the fd, which should be readable, O_NONBLOCK
 111     *   - set up and initialise buffer, which should be big enough
 112     *     for one line plus its trailing newline, and be empty
 113     *     with start==base
 114     *   - in your beforepoll_fn, be interested in POLLIN
 115     *   - in your afterpoll_fn, repeatedly call this function
 116     *     until it doesn't return `nothing'
 117     *   - after you're done, simply close fd and free or reset buf
 118     * State on return from async_linebuf_read depends on return value:
 119     *
 120     *   async_linebuf_nothing:
 121     *
 122     *      No complete lines available right now.  You should return
 123     *      from afterpoll.  buf should be left untouched until the
 124     *      next call to async_linebuf_read.
 125     *
 126     *   async_linebuf_ok:
 127     *
 128     *      buf->base contains a input line as a nul-terminated string
 129     *      (\n replaced by \0); *emsg_out==0.  You must call
 130     *      async_linebuf_read again before returning from afterpoll.
 131     *
 132     *   async_linebuf_eof:
 133     *
 134     *      EOF on stream.  buf->base contains any partial
 135     *      (non-newline-terminated) line; *emsg_out!=0 iff there was
 136     *      such a partial line.  You can call async_linebuf_read again
 137     *      if you like but it will probably just return eof again.
 138     *
 139     *   broken:
 140     *
 141     *      Fatal problem (might be overly long lines, nuls in input
 142     *      data, bad bits in pfd->revents, errors from read, etc.)
 143     *
 144     *      *emsg_out is the error message describing the problem;
 145     *      this message might be stored in buf, might be from
 146     *      strerror, or might be a constant.
 147     *
 148     *      You must not call async_linebuf_read again.  buf contents
 149     *      is undefined: it is only safe to reset or free.
 150     *
 151     * While using this function, do not look at buf->start or ->size
 152     * or anything after the first '\0' in buf.
 153     *
 154     * If you decide to stop reading with async_linebuf_read that's
 155     * fine and you can reset or free buf, but you risk missing some
 156     * read-but-not-reported data.
 157     */
 158
 159 /*----- some handy macros -----*/
 160
 161 #define MINMAX(ae,be,op) ({                     \
 162         typeof((ae)) a=(ae);                    \
 163         typeof((be)) b=(be);                    \
 164         a op b ? a : b;                         \
 165     })
 166 #define MAX(a,b) MINMAX((a),(b),>)
 167 #define MIN(a,b) MINMAX((a),(b),<)
 168
 169 #define MAX_RAW(a,b) ((a)>(b)?(a):(b))
 170 #define MIN_RAW(a,b) ((a)<(b)?(a):(b))
 171
 172 static inline bool_t iswouldblock(int e)
 173     { return e==EWOULDBLOCK || e==EAGAIN; }
 174
 175 #endif /* util_h */