Change year in copyright message to 2012.
[paraslash.git] / para.h
1 /*
2 * Copyright (C) 1997-2012 Andre Noll <maan@systemlinux.org>
3 *
4 * Licensed under the GPL v2. For licencing details see COPYING.
5 */
6
7 /** \file para.h global paraslash definitions */
8
9 #include "config.h"
10
11 #include <sys/stat.h>
12 #include <fcntl.h>
13 #include <sys/wait.h>
14 #include <stdio.h>
15 #include <stdlib.h>
16 #include <time.h> /* time(), localtime() */
17 #include <unistd.h>
18 #include <errno.h>
19 #include <limits.h>
20 #include <stdarg.h>
21 #include <ctype.h>
22 #include <netinet/in.h>
23 #include <arpa/inet.h>
24 #include <sys/socket.h>
25 #include <sys/un.h> /* needed by create_pf_socket */
26 #include <string.h>
27 #include <assert.h>
28 #include <stdbool.h>
29 #include "gcc-compat.h"
30
31 /** used in various contexts */
32 #define MAXLINE 255
33
34 /** Compute the minimum of \a x and \a y. */
35 #define PARA_MIN(x, y) ({ \
36 typeof(x) _min1 = (x); \
37 typeof(y) _min2 = (y); \
38 (void) (&_min1 == &_min2); \
39 _min1 < _min2 ? _min1 : _min2; })
40
41 /** Compute the maximum of \a x and \a y. */
42 #define PARA_MAX(x, y) ({ \
43 typeof(x) _max1 = (x); \
44 typeof(y) _max2 = (y); \
45 (void) (&_max1 == &_max2); \
46 _max1 < _max2 ? _max2 : _max1; })
47
48 /** Compute the absolute value of \a x. */
49 #define PARA_ABS(x) ({ \
50 typeof(x) _x = (x); \
51 _x > 0? _x : -_x; })
52
53
54 extern __printf_2_3 void (*para_log)(int, const char*, ...);
55 /**
56 * Define a standard log function that always writes to stderr.
57 *
58 * \param funcname The name of the function to be defined.
59 *
60 * \param loglevel_barrier If the loglevel of the current message
61 * is less than that, the message is going to be ignored.
62 *
63 */
64 #define DEFINE_STDERR_LOGGER(funcname, loglevel_barrier) \
65 __printf_2_3 void funcname(int ll, const char* fmt,...) \
66 { \
67 va_list argp; \
68 if (ll < loglevel_barrier) \
69 return; \
70 va_start(argp, fmt); \
71 vfprintf(stderr, fmt, argp); \
72 va_end(argp); \
73 }
74 #define INIT_STDERR_LOGGING(loglevel_barrier) \
75 DEFINE_STDERR_LOGGER(stderr_log, loglevel_barrier); \
76 __printf_2_3 void (*para_log)(int, const char*, ...) = stderr_log;
77
78 /** Sent by para_client to initiate the authentication procedure. */
79 #define AUTH_REQUEST_MSG "auth rsa "
80 /** Sent by para_server for commands that expect a data file. */
81 #define AWAITING_DATA_MSG "\nAwaiting Data."
82 /** Sent by para_server if authentication was successful. */
83 #define PROCEED_MSG "Proceed."
84 /** Length of the \p PROCEED_MSG string. */
85 #define PROCEED_MSG_LEN strlen(PROCEED_MSG)
86 /** Sent by para_client to indicate the end of the command line. */
87 #define EOC_MSG "\nEnd of Command."
88
89 /* exec */
90 int para_exec_cmdline_pid(pid_t *pid, const char *cmdline, int *fds);
91
92 /* time */
93 int tv_diff(const struct timeval *b, const struct timeval *a, struct timeval *diff);
94 long unsigned tv2ms(const struct timeval*);
95 void d2tv(double, struct timeval*);
96 void tv_add(const struct timeval*, const struct timeval *, struct timeval *);
97 void tv_scale(const unsigned long, const struct timeval *, struct timeval *);
98 void tv_divide(const unsigned long divisor, const struct timeval *tv,
99 struct timeval *result);
100 int tv_convex_combination(const long a, const struct timeval *tv1,
101 const long b, const struct timeval *tv2,
102 struct timeval *result);
103 void ms2tv(const long unsigned n, struct timeval *tv);
104 void compute_chunk_time(long unsigned chunk_num,
105 struct timeval *chunk_tv, struct timeval *stream_start,
106 struct timeval *result);
107
108 /** The enum of all status items. */
109 enum status_items {STATUS_ITEM_ENUM NUM_STAT_ITEMS};
110 extern const char *status_item_list[];
111 /** Loop over each status item. */
112 #define FOR_EACH_STATUS_ITEM(i) for (i = 0; i < NUM_STAT_ITEMS; i++)
113 int for_each_stat_item(char *item_buf, size_t num_bytes,
114 int (*item_handler)(int, char *));
115
116 /**
117 * Write a log message to a dynamically allocated string.
118 *
119 * \param fmt Usual format string.
120 * \param p Result pointer.
121 *
122 * \sa printf(3). */
123 #define PARA_VSPRINTF(fmt, p) \
124 { \
125 int n; \
126 size_t size = 100; \
127 p = para_malloc(size); \
128 while (1) { \
129 va_list ap; \
130 /* Try to print in the allocated space. */ \
131 va_start(ap, fmt); \
132 n = vsnprintf(p, size, fmt, ap); \
133 va_end(ap); \
134 /* If that worked, return the string. */ \
135 if (n > -1 && n < size) \
136 break; \
137 /* Else try again with more space. */ \
138 if (n > -1) /* glibc 2.1 */ \
139 size = n + 1; /* precisely what is needed */ \
140 else /* glibc 2.0 */ \
141 size *= 2; /* twice the old size */ \
142 p = para_realloc(p, size); \
143 } \
144 }
145
146 /**
147 * Return a random non-negative integer in an interval.
148 *
149 * \param max Determines maximal possible return value.
150 *
151 * \return An integer between zero and \p max - 1, inclusively.
152 */
153 _static_inline_ long int para_random(unsigned max)
154 {
155 return ((max + 0.0) * (random() / (RAND_MAX + 1.0)));
156 }
157
158 /** Round up x to next multiple of y. */
159 #define ROUND_UP(x, y) ({ \
160 const typeof(y) _divisor = y; \
161 ((x) + _divisor - 1) / _divisor * _divisor; })
162
163 /** Round down x to multiple of y. */
164 #define ROUND_DOWN(x, y) ({ \
165 const typeof(y) _divisor = y; \
166 (x) / _divisor * _divisor; })
167
168 /** Divide and round up to next integer. */
169 #define DIV_ROUND_UP(x, y) ({ \
170 typeof(y) _divisor = y; \
171 ((x) + _divisor - 1) / _divisor; })
172
173 /**
174 * Assert a build-time dependency, as an expression.
175 *
176 * \param cond The compile-time condition which must be true.
177 *
178 * Compilation will fail if the condition isn't true, or can't be evaluated by
179 * the compiler. This can be used in an expression: its value is "0".
180 *
181 * Taken from ccan.
182 */
183 #define EXPR_BUILD_ASSERT(cond) (sizeof(char [1 - 2 * !(cond)]) - 1)
184
185 /** &a[0] degrades to a pointer: a different type from an array */
186 #define _array_size_chk(arr) EXPR_BUILD_ASSERT(\
187 !__builtin_types_compatible_p(typeof(arr), typeof(&(arr)[0])))
188 /** Get the size of an array */
189 #define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
190
191 /**
192 * Wrapper for isspace.
193 * NetBSD needs this.
194 */
195 /*
196 * The values should be cast to an unsigned char first, then to int.
197 * Why? Because the isdigit (as do all other is/to functions/macros)
198 * expect a number from 0 upto and including 255 as their (int) argument.
199 * Because char is signed on most systems, casting it to int immediately
200 * gives the functions an argument between -128 and 127 (inclusive),
201 * which they will use as an array index, and which will thus fail
202 * horribly for characters which have their most significant bit set.
203 */
204 #define para_isspace(c) isspace((int)(unsigned char)(c))
205
206 /** Data that indicates an eof-condition for a fec-encoded stream. */
207 #define FEC_EOF_PACKET "\xec\x0d\xcc\xfe\0\0\0\0" \
208 "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0" "\0\0\0\0\0\0\0\0"
209 /** The number of bytes of the \a FEC_EOF_PACKET. */
210 #define FEC_EOF_PACKET_LEN 32
211
212 /** Used to avoid a shortcoming in vim's syntax highlighting. */
213 #define EMBRACE(...) { __VA_ARGS__}
214
215 /** A nice cup of STFU for Mr gcc. */
216 #define do_nothing do {/* nothing */} while (0)
217
218 /**
219 * The sample formats supported by paraslash.
220 *
221 * It may be determined by one of the following sources:
222 *
223 * 1. The decoding filter (para_audiod only). In this case, it is always
224 * \p SF_S16_LE which is the canonical format used within decoders.
225 *
226 * 2. The wav header (para_write only).
227 *
228 * 3. The --format option of para_write.
229 */
230 #define SAMPLE_FORMATS \
231 SAMPLE_FORMAT(SF_S8, "8 bit signed"), \
232 SAMPLE_FORMAT(SF_U8, "8 bit unsigned"), \
233 SAMPLE_FORMAT(SF_S16_LE, "16 bit signed, little endian"), \
234 SAMPLE_FORMAT(SF_S16_BE, "16 bit signed, big endian"), \
235 SAMPLE_FORMAT(SF_U16_LE, "16 bit unsigned, little endian"), \
236 SAMPLE_FORMAT(SF_U16_BE, "16 bit unsigned, big endian"), \
237
238 /** \cond sample_format */
239 #define SAMPLE_FORMAT(a, b) a
240 enum sample_format {SAMPLE_FORMATS};
241 #undef SAMPLE_FORMAT
242 #define SAMPLE_FORMAT(a, b) b
243 /** \endcond sample_format */
244
245 /** Debug loglevel, gets really noisy. */
246 #define LL_DEBUG 0
247 /** Still noisy, but won't fill your disk. */
248 #define LL_INFO 1
249 /** Normal, but significant event. */
250 #define LL_NOTICE 2
251 /** Unexpected event that can be handled. */
252 #define LL_WARNING 3
253 /** Unhandled error condition. */
254 #define LL_ERROR 4
255 /** System might be unreliable. */
256 #define LL_CRIT 5
257 /** Last message before exit. */
258 #define LL_EMERG 6
259 /** Number of all loglevels. */
260 #define NUM_LOGLEVELS 7
261
262 /** Log messages with lower priority than that will not be compiled in. */
263 #define COMPILE_TIME_LOGLEVEL 0
264
265 /** \cond log */
266 #if LL_DEBUG >= COMPILE_TIME_LOGLEVEL
267 #define PARA_DEBUG_LOG(f,...) para_log(LL_DEBUG, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
268 #else
269 #define PARA_DEBUG_LOG(...) do {;} while (0)
270 #endif
271
272 #if LL_INFO >= COMPILE_TIME_LOGLEVEL
273 #define PARA_INFO_LOG(f,...) para_log(LL_INFO, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
274 #else
275 #define PARA_INFO_LOG(...) do {;} while (0)
276 #endif
277
278 #if LL_NOTICE >= COMPILE_TIME_LOGLEVEL
279 #define PARA_NOTICE_LOG(f,...) para_log(LL_NOTICE, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
280 #else
281 #define PARA_NOTICE_LOG(...) do {;} while (0)
282 #endif
283
284 #if LL_WARNING >= COMPILE_TIME_LOGLEVEL
285 #define PARA_WARNING_LOG(f,...) para_log(LL_WARNING, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
286 #else
287 #define PARA_WARNING_LOG(...) do {;} while (0)
288 #endif
289
290 #if LL_ERROR >= COMPILE_TIME_LOGLEVEL
291 #define PARA_ERROR_LOG(f,...) para_log(LL_ERROR, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
292 #else
293 #define PARA_ERROR_LOG(...) do {;} while (0)
294 #endif
295
296 #if LL_CRIT >= COMPILE_TIME_LOGLEVEL
297 #define PARA_CRIT_LOG(f,...) para_log(LL_CRIT, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
298 #else
299 #define PARA_CRIT_LOG(...) do {;} while (0)
300 #endif
301
302 #if LL_EMERG >= COMPILE_TIME_LOGLEVEL
303 #define PARA_EMERG_LOG(f,...) para_log(LL_EMERG, "%s: " f, __FUNCTION__, ## __VA_ARGS__)
304 #else
305 #define PARA_EMERG_LOG(...)
306 #endif
307 /** \endcond log */