| 1 | /* |
| 2 | * This file is part of secnet. |
| 3 | * See README for full list of copyright holders. |
| 4 | * |
| 5 | * secnet is free software; you can redistribute it and/or modify it |
| 6 | * under the terms of the GNU General Public License as published by |
| 7 | * the Free Software Foundation; either version d of the License, or |
| 8 | * (at your option) any later version. |
| 9 | * |
| 10 | * secnet is distributed in the hope that it will be useful, but |
| 11 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 13 | * General Public License for more details. |
| 14 | * |
| 15 | * You should have received a copy of the GNU General Public License |
| 16 | * version 3 along with secnet; if not, see |
| 17 | * https://www.gnu.org/licenses/gpl.html. |
| 18 | */ |
| 19 | |
| 20 | #ifndef util_h |
| 21 | #define util_h |
| 22 | |
| 23 | #include "secnet.h" |
| 24 | #include <gmp.h> |
| 25 | |
| 26 | #include "hackypar.h" |
| 27 | |
| 28 | #define BUF_ASSERT_FREE(buf) do { buffer_assert_free((buf), \ |
| 29 | __FILE__,__LINE__); } \ |
| 30 | while(0) |
| 31 | #define BUF_ASSERT_USED(buf) do { buffer_assert_used((buf), \ |
| 32 | __FILE__,__LINE__); } \ |
| 33 | while(0) |
| 34 | #define BUF_ALLOC(buf,own) do { buffer_assert_free((buf),__FILE__,__LINE__); \ |
| 35 | (buf)->free=False; (buf)->owner=(own); (buf)->start=(buf)->base; \ |
| 36 | (buf)->size=0; } while(0) |
| 37 | #define BUF_FREE(buf) do { (buf)->free=True; } while(0) |
| 38 | |
| 39 | extern void buffer_assert_free(struct buffer_if *buffer, cstring_t file, |
| 40 | int line); |
| 41 | extern void buffer_assert_used(struct buffer_if *buffer, cstring_t file, |
| 42 | int line); |
| 43 | extern void buffer_new(struct buffer_if *buffer, int32_t len); |
| 44 | extern void buffer_init(struct buffer_if *buffer, int32_t max_start_pad); |
| 45 | extern void buffer_destroy(struct buffer_if *buffer); |
| 46 | extern void buffer_copy(struct buffer_if *dst, const struct buffer_if *src); |
| 47 | extern void *buf_append(struct buffer_if *buf, int32_t amount); |
| 48 | extern void *buf_prepend(struct buffer_if *buf, int32_t amount); |
| 49 | extern void *buf_unappend(struct buffer_if *buf, int32_t amount); |
| 50 | extern void *buf_unprepend(struct buffer_if *buf, int32_t amount); |
| 51 | |
| 52 | /* |
| 53 | * void BUF_ADD_BYTES(append, struct buffer_if*, const void*, int32_t size); |
| 54 | * void BUF_ADD_BYTES(prepend, struct buffer_if*, const void*, int32_t size); |
| 55 | * void BUF_GET_BYTES(unappend, struct buffer_if*, void*, int32_t size); |
| 56 | * void BUF_GET_BYTES(unprepend, struct buffer_if*, void*, int32_t size); |
| 57 | * // all of these evaluate size twice |
| 58 | * |
| 59 | * void BUF_ADD_OBJ(append, struct_buffer_if*, const OBJECT& something); |
| 60 | * void BUF_ADD_OBJ(prepend, struct_buffer_if*, const OBJECT& something); |
| 61 | * void BUF_GET_OBJ(unappend, struct_buffer_if*, OBJECT& something); |
| 62 | * void BUF_GET_OBJ(unprepend, struct_buffer_if*, OBJECT& something); |
| 63 | */ |
| 64 | #define BUF_ADD_BYTES(appendprepend, bufp, datap, size) \ |
| 65 | (buf_un##appendprepend /* ensures we have correct direction */, \ |
| 66 | memcpy(buf_##appendprepend((bufp),(size)),(datap),(size))) |
| 67 | #define BUF_ADD_OBJ(appendprepend, bufp, obj) \ |
| 68 | BUF_ADD_BYTES(appendprepend,(bufp),&(obj),sizeof((obj))) |
| 69 | #define BUF_GET_BYTES(unappendunprepend, bufp, datap, size) \ |
| 70 | (BUF_GET__DOESNOTEXIST__buf_un##unappendunprepend, \ |
| 71 | memcpy((datap),buf_##unappendunprepend((bufp),(size)),(size))) |
| 72 | #define BUF_GET_OBJ(unappendunprepend, bufp, obj) \ |
| 73 | BUF_ADD_BYTES(unappendunprepend,&(obj),(bufp),sizeof((obj))) |
| 74 | #define BUF_GET__DOESNOTEXIST__buf_ununappend 0 |
| 75 | #define BUF_GET__DOESNOTEXIST__buf_ununprepend 0 |
| 76 | |
| 77 | static inline int32_t buf_remaining_space(const struct buffer_if *buf) |
| 78 | { |
| 79 | return (buf->base + buf->alloclen) - (buf->start + buf->size); |
| 80 | } |
| 81 | |
| 82 | extern void buffer_readonly_view(struct buffer_if *n, const void*, int32_t len); |
| 83 | extern void buffer_readonly_clone(struct buffer_if *n, const struct buffer_if*); |
| 84 | /* Caller must only use unappend, unprepend et al. on n. |
| 85 | * New buffer state (in n) before this can be undefined. After use, |
| 86 | * it must NOT be freed. */ |
| 87 | |
| 88 | extern void buf_append_string(struct buffer_if *buf, cstring_t s); |
| 89 | |
| 90 | extern void read_mpbin(MP_INT *a, uint8_t *bin, int binsize); |
| 91 | |
| 92 | extern char *write_mpstring(MP_INT *a); |
| 93 | |
| 94 | extern int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen); |
| 95 | |
| 96 | extern struct log_if *init_log(list_t *loglist); |
| 97 | |
| 98 | extern void send_nak(const struct comm_addr *dest, uint32_t our_index, |
| 99 | uint32_t their_index, uint32_t msgtype, |
| 100 | struct buffer_if *buf, const char *logwhy); |
| 101 | |
| 102 | extern int consttime_memeq(const void *s1, const void *s2, size_t n); |
| 103 | |
| 104 | const char *iaddr_to_string(const union iaddr *ia); |
| 105 | int iaddr_socklen(const union iaddr *ia); |
| 106 | |
| 107 | void string_item_to_iaddr(const item_t *item, uint16_t port, union iaddr *ia, |
| 108 | const char *desc); |
| 109 | |
| 110 | |
| 111 | /* |
| 112 | * SBUF_DEFINE(int nbufs, size_t size); |
| 113 | * // Generates a number of definitions and statements organising |
| 114 | * // nbufs rotating char[size] buffers such that subsequent code |
| 115 | * // may refer to: |
| 116 | * char *const SBUF; |
| 117 | */ |
| 118 | #define SBUF_DEFINE(nbufs, size) \ |
| 119 | static int static_bufs__bufnum; \ |
| 120 | static char static_bufs__bufs[(nbufs)][(size)]; \ |
| 121 | static_bufs__bufnum++; \ |
| 122 | static_bufs__bufnum %= (nbufs); \ |
| 123 | static_bufs__bufs[static_bufs__bufnum] |
| 124 | #define SBUF (static_bufs__bufs[static_bufs__bufnum]) |
| 125 | |
| 126 | /*----- line-buffered asynch input -----*/ |
| 127 | |
| 128 | enum async_linebuf_result { |
| 129 | async_linebuf_nothing, |
| 130 | async_linebuf_ok, |
| 131 | async_linebuf_eof, |
| 132 | async_linebuf_broken, |
| 133 | }; |
| 134 | |
| 135 | const char *pollbadbit(int revents); /* returns 0, or bad bit description */ |
| 136 | |
| 137 | enum async_linebuf_result |
| 138 | async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf, |
| 139 | const char **emsg_out); |
| 140 | /* Implements reading whole lines, asynchronously. Use like |
| 141 | * this: |
| 142 | * - set up the fd, which should be readable, O_NONBLOCK |
| 143 | * - set up and initialise buffer, which should be big enough |
| 144 | * for one line plus its trailing newline, and be empty |
| 145 | * with start==base |
| 146 | * - in your beforepoll_fn, be interested in POLLIN |
| 147 | * - in your afterpoll_fn, repeatedly call this function |
| 148 | * until it doesn't return `nothing' |
| 149 | * - after you're done, simply close fd and free or reset buf |
| 150 | * State on return from async_linebuf_read depends on return value: |
| 151 | * |
| 152 | * async_linebuf_nothing: |
| 153 | * |
| 154 | * No complete lines available right now. You should return |
| 155 | * from afterpoll. buf should be left untouched until the |
| 156 | * next call to async_linebuf_read. |
| 157 | * |
| 158 | * async_linebuf_ok: |
| 159 | * |
| 160 | * buf->base contains a input line as a nul-terminated string |
| 161 | * (\n replaced by \0); *emsg_out==0. You must call |
| 162 | * async_linebuf_read again before returning from afterpoll. |
| 163 | * |
| 164 | * async_linebuf_eof: |
| 165 | * |
| 166 | * EOF on stream. buf->base contains any partial |
| 167 | * (non-newline-terminated) line; *emsg_out!=0 iff there was |
| 168 | * such a partial line. You can call async_linebuf_read again |
| 169 | * if you like but it will probably just return eof again. |
| 170 | * |
| 171 | * broken: |
| 172 | * |
| 173 | * Fatal problem (might be overly long lines, nuls in input |
| 174 | * data, bad bits in pfd->revents, errors from read, etc.) |
| 175 | * |
| 176 | * *emsg_out is the error message describing the problem; |
| 177 | * this message might be stored in buf, might be from |
| 178 | * strerror, or might be a constant. |
| 179 | * |
| 180 | * You must not call async_linebuf_read again. buf contents |
| 181 | * is undefined: it is only safe to reset or free. |
| 182 | * |
| 183 | * While using this function, do not look at buf->start or ->size |
| 184 | * or anything after the first '\0' in buf. |
| 185 | * |
| 186 | * If you decide to stop reading with async_linebuf_read that's |
| 187 | * fine and you can reset or free buf, but you risk missing some |
| 188 | * read-but-not-reported data. |
| 189 | */ |
| 190 | |
| 191 | /*----- some handy macros -----*/ |
| 192 | |
| 193 | #define MINMAX(ae,be,op) ({ \ |
| 194 | typeof((ae)) a=(ae); \ |
| 195 | typeof((be)) b=(be); \ |
| 196 | a op b ? a : b; \ |
| 197 | }) |
| 198 | #define MAX(a,b) MINMAX((a),(b),>) |
| 199 | #define MIN(a,b) MINMAX((a),(b),<) |
| 200 | |
| 201 | #define MAX_RAW(a,b) ((a)>(b)?(a):(b)) |
| 202 | #define MIN_RAW(a,b) ((a)<(b)?(a):(b)) |
| 203 | |
| 204 | static inline bool_t iswouldblock(int e) |
| 205 | { return e==EWOULDBLOCK || e==EAGAIN; } |
| 206 | |
| 207 | #endif /* util_h */ |