common/util.h

   1 /*
   2  * util.h - useful functions header
   3  *
   4  * Copyright © 2007-2008 Julien Danjou <julien@danjou.info>
   5  * Copyright © 2006 Pierre Habouzit <madcoder@debian.org>
   6  *
   7  * This program is free software; you can redistribute it and/or modify
   8  * it under the terms of the GNU General Public License as published by
   9  * the Free Software Foundation; either version 2 of the License, or
  10  * (at your option) any later version.
  11  *
  12  * This program is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15  * GNU General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU General Public License along
  18  * with this program; if not, write to the Free Software Foundation, Inc.,
  19  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  */
  22
  23 #ifndef AWESOME_COMMON_UTIL_H
  24 #define AWESOME_COMMON_UTIL_H
  25
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include <stdbool.h>
  29 #include <stdarg.h>
  30 #include <assert.h>
  31
  32 #if !(defined (__FreeBSD__) || defined(__OpenBSD__))
  33 #include <alloca.h>
  34 #endif
  35
  36 #include "tokenize.h"
  37
  38 typedef enum
  39 {
  40     East,
  41     South,
  42     North,
  43 } orientation_t;
  44
  45 /** A list of possible position, not sex related */
  46 typedef enum
  47 {
  48     Top,
  49     Bottom,
  50     Right,
  51     Left,
  52     Floating
  53 } position_t;
  54
  55 /** Link a name to a function */
  56 typedef struct
  57 {
  58     const char *name;
  59     void *func;
  60 } name_func_link_t;
  61
  62 /** \brief replace \c NULL strings with emtpy strings */
  63 #define NONULL(x)       (x ? x : "")
  64
  65 #define DO_NOTHING(...)
  66
  67 #undef MAX
  68 #undef MIN
  69 #define MAX(a,b) ((a) < (b) ? (b) : (a))
  70 #define MIN(a,b) ((a) < (b) ? (a) : (b))
  71
  72 #define ssizeof(foo)            (ssize_t)sizeof(foo)
  73 #define countof(foo)            (ssizeof(foo) / ssizeof(foo[0]))
  74
  75 #define p_alloca(type, count)                                \
  76         ((type *)memset(alloca(sizeof(type) * (count)),      \
  77                         0, sizeof(type) * (count)))
  78
  79 #define p_alloc_nr(x)           (((x) + 16) * 3 / 2)
  80 #define p_new(type, count)      ((type *)xmalloc(sizeof(type) * (count)))
  81 #define p_clear(p, count)       ((void)memset((p), 0, sizeof(*(p)) * (count)))
  82 #define p_realloc(pp, count)    xrealloc((void*)(pp), sizeof(**(pp)) * (count))
  83 #define p_dup(p, count)         xmemdup((p), sizeof(*(p)) * (count))
  84 #define p_grow(pp, goalnb, allocnb)                  \
  85     do {                                             \
  86         if ((goalnb) > *(allocnb)) {                 \
  87             if (p_alloc_nr(*(allocnb)) < (goalnb)) { \
  88                 *(allocnb) = (goalnb);               \
  89             } else {                                 \
  90                 *(allocnb) = p_alloc_nr(*(allocnb)); \
  91             }                                        \
  92             p_realloc(pp, *(allocnb));               \
  93         }                                            \
  94     } while (0)
  95
  96
  97 #ifdef __GNUC__
  98
  99 #define p_delete(mem_pp)                           \
 100     do {                                           \
 101         typeof(**(mem_pp)) **__ptr = (mem_pp);     \
 102         free(*__ptr);                              \
 103         *__ptr = NULL;                             \
 104     } while(0)
 105
 106 #define likely(expr)    __builtin_expect(!!(expr), 1)
 107 #define unlikely(expr)  __builtin_expect((expr), 0)
 108
 109 #else
 110
 111 #define p_delete(mem_p)                            \
 112     do {                                           \
 113         void *__ptr = (mem_p);                     \
 114         free(*__ptr);                              \
 115         *(void **)__ptr = NULL;                    \
 116     } while (0)
 117
 118 #define likely(expr)    expr
 119 #define unlikely(expr)  expr
 120
 121 #endif
 122
 123 static inline void * __attribute__ ((malloc)) xmalloc(ssize_t size)
 124 {
 125     void *ptr;
 126
 127     if(size <= 0)
 128         return NULL;
 129
 130     ptr = calloc(1, size);
 131
 132     if(!ptr)
 133         abort();
 134
 135     return ptr;
 136 }
 137
 138 static inline void
 139 xrealloc(void **ptr, ssize_t newsize)
 140 {
 141     if(newsize <= 0)
 142         p_delete(ptr);
 143     else
 144     {
 145         *ptr = realloc(*ptr, newsize);
 146         if(!*ptr)
 147             abort();
 148     }
 149 }
 150
 151 /** Duplicate a memory zone.
 152  * \param src The source.
 153  * \param size The source size.
 154  * \return The memory address of the copy.
 155  */
 156 static inline void *xmemdup(const void *src, ssize_t size)
 157 {
 158     return memcpy(xmalloc(size), src, size);
 159 }
 160
 161 /** \brief \c NULL resistant strlen.
 162  *
 163  * Unlike it's libc sibling, a_strlen returns a ssize_t, and supports its
 164  * argument being NULL.
 165  *
 166  * \param[in] s the string.
 167  * \return the string length (or 0 if \c s is \c NULL).
 168  */
 169 static inline ssize_t a_strlen(const char *s)
 170 {
 171     return s ? strlen(s) : 0;
 172 }
 173
 174 /** \brief \c NULL resistant strnlen.
 175  *
 176  * Unlike it's GNU libc sibling, a_strnlen returns a ssize_t, and supports
 177  * its argument being NULL.
 178  *
 179  * The a_strnlen() function returns the number of characters in the string
 180  * pointed to by \c s, not including the terminating \c \\0 character, but at
 181  * most \c n. In doing this, a_strnlen() looks only at the first \c n
 182  * characters at \c s and never beyond \c s+n.
 183  *
 184  * \param[in]  s    the string.
 185  * \param[in]  n    the maximum length to return.
 186  * \return \c a_strlen(s) if less than \c n, else \c n.
 187  */
 188 static inline ssize_t a_strnlen(const char *s, ssize_t n)
 189 {
 190     if (s)
 191     {
 192         const char *p = memchr(s, '\0', n);
 193         return p ? p - s : n;
 194     }
 195     return 0;
 196 }
 197
 198 /** \brief \c NULL resistant strdup.
 199  *
 200  * the a_strdup() function returns a pointer to a new string, which is a
 201  * duplicate of \c s. Memory should be freed using p_delete().
 202  *
 203  * \warning when s is \c "", it returns NULL !
 204  *
 205  * \param[in] s the string to duplicate.
 206  * \return a pointer to the duplicated string.
 207  */
 208 static inline
 209 char *a_strdup(const char *s)
 210 {
 211     ssize_t len = a_strlen(s);
 212     return len ? p_dup(s, len + 1) : NULL;
 213 }
 214
 215 /** \brief safe limited strdup.
 216  *
 217  * Copies at most min(<tt>n-1</tt>, \c l) characters from \c src into a newly
 218  * allocated buffer, always adding a final \c \\0, and returns that buffer.
 219  *
 220  * \warning when s is \c "" or l is 0, it returns NULL !
 221  *
 222  * \param[in]  s        source string.
 223  * \param[in]  l        maximum number of chars to copy.
 224  * \return a newly allocated buffer containing the first \c l chars of \c src.
 225 */
 226 static inline
 227 char * a_strndup(const char *s, ssize_t l)
 228 {
 229     ssize_t len = MIN(a_strlen(s), l);
 230     if(len)
 231     {
 232         char *p = p_dup(s, len + 1);
 233         p[len] = '\0';
 234         return p;
 235     }
 236     return NULL;
 237 }
 238
 239 /** \brief \c NULL resistant strcmp.
 240  * \param[in]  a     the first string.
 241  * \param[in]  b     the second string.
 242  * \return <tt>strcmp(a, b)</tt>, and treats \c NULL strings like \c ""
 243  * ones.
 244  */
 245 static inline int a_strcmp(const char *a, const char *b)
 246 {
 247     return strcmp(NONULL(a), NONULL(b));
 248 }
 249
 250 /** \brief \c NULL resistant strcasecmp.
 251  * \param[in]  a     the first string.
 252  * \param[in]  b     the second string.
 253  * \return <tt>strcasecmp(a, b)</tt>, and treats \c NULL strings like \c ""
 254  * ones.
 255  */
 256 static inline int a_strcasecmp(const char *a, const char *b)
 257 {
 258     return strcasecmp(NONULL(a), NONULL(b));
 259 }
 260
 261 /** \brief \c NULL resistant strncmp.
 262  * \param[in]  a     the first string.
 263  * \param[in]  b     the second string.
 264  * \param[in]  n     the number of maximum chars to compare.
 265  * \return <tt>strncmp(a, b, n)</tt>, and treats \c NULL strings like \c ""
 266  * ones.
 267  */
 268 static inline int a_strncmp(const char *a, const char *b, ssize_t n)
 269 {
 270     return strncmp(NONULL(a), NONULL(b), n);
 271 }
 272
 273 ssize_t a_strncpy(char *dst, ssize_t n, const char *src, ssize_t l) __attribute__((nonnull(1)));
 274 ssize_t a_strcpy(char *dst, ssize_t n, const char *src) __attribute__((nonnull(1)));
 275
 276 /** \brief safe strcat.
 277  *
 278  * The a_strcat() function appends the string \c src at the end of the buffer
 279  * \c dst if space is available.
 280  *
 281  * \param[in]  dst   destination buffer.
 282  * \param[in]  n     size of the buffer, Negative sizes are allowed.
 283  * \param[in]  src   the string to append.
 284  * \return <tt>a_strlen(dst) + a_strlen(src)</tt>
 285  */
 286 static inline ssize_t a_strcat(char *dst, ssize_t n, const char *src)
 287 {
 288     ssize_t dlen = a_strnlen(dst, n - 1);
 289     return dlen + a_strcpy(dst + dlen, n - dlen, src);
 290 }
 291
 292 /** \brief safe strncat.
 293  *
 294  * The a_strncat() function appends at most \c n chars from the string \c src
 295  * at the end of the buffer \c dst if space is available.
 296  *
 297  * \param[in]  dst   destination buffer.
 298  * \param[in]  n     size of the buffer, Negative sizes are allowed.
 299  * \param[in]  src   the string to append.
 300  * \param[in]  l     maximum number of chars of src to consider.
 301  * \return the smallest value between <tt>a_strlen(dst) + a_strlen(src)</tt>
 302  * and <tt>a_strlen(dst) + l</tt>
 303  */
 304 static inline ssize_t
 305 a_strncat(char *dst, ssize_t n, const char *src, ssize_t l)
 306 {
 307     ssize_t dlen = a_strnlen(dst, n - 1);
 308     return dlen + a_strncpy(dst + dlen, n - dlen, src, l);
 309 }
 310
 311 /** \brief convert a string to a boolean value.
 312  *
 313  * The a_strtobool() function converts a string \c s into a boolean.
 314  * It recognizes the strings "true", "on", "yes" and "1".
 315  *
 316  * \param[in]  s     the string to convert
 317  * \return true if the string is recognized as possibly true, false otherwise.
 318  */
 319 static inline bool
 320 a_strtobool(const char *s, ssize_t len)
 321 {
 322     switch(a_tokenize(s, len))
 323     {
 324         case A_TK_TRUE:
 325         case A_TK_YES:
 326         case A_TK_ON:
 327         case A_TK_1:
 328           return true;
 329         default:
 330           return false;
 331     }
 332 }
 333
 334 #define fatal(string, ...) _fatal(__LINE__, \
 335                                   __FUNCTION__, \
 336                                   string, ## __VA_ARGS__)
 337 void _fatal(int, const char *, const char *, ...)
 338     __attribute__ ((noreturn)) __attribute__ ((format(printf, 3, 4)));
 339
 340 #define warn(string, ...) _warn(__LINE__, \
 341                                 __FUNCTION__, \
 342                                 string, ## __VA_ARGS__)
 343 void _warn(int, const char *, const char *, ...)
 344     __attribute__ ((format(printf, 3, 4)));
 345
 346 position_t position_fromstr(const char *, ssize_t);
 347 const char * position_tostr(position_t);
 348 orientation_t orientation_fromstr(const char *, ssize_t);
 349 const char * orientation_tostr(orientation_t);
 350 void *name_func_lookup(const char *, const name_func_link_t *);
 351 const char * name_func_rlookup(void *, const name_func_link_t *);
 352 void a_exec(const char *);
 353 char ** a_strsplit(const char *, ssize_t, char);
 354
 355 #endif
 356 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80