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 static inline void *xmemdup(const void *src, ssize_t size)
 152 {
 153     return memcpy(xmalloc(size), src, size);
 154 }
 155
 156 /** \brief \c NULL resistant strlen.
 157  *
 158  * Unlike it's libc sibling, a_strlen returns a ssize_t, and supports its
 159  * argument being NULL.
 160  *
 161  * \param[in] s the string.
 162  * \return the string length (or 0 if \c s is \c NULL).
 163  */
 164 static inline ssize_t a_strlen(const char *s)
 165 {
 166     return s ? strlen(s) : 0;
 167 }
 168
 169 /** \brief \c NULL resistant strnlen.
 170  *
 171  * Unlike it's GNU libc sibling, a_strnlen returns a ssize_t, and supports
 172  * its argument being NULL.
 173  *
 174  * The a_strnlen() function returns the number of characters in the string
 175  * pointed to by \c s, not including the terminating \c \\0 character, but at
 176  * most \c n. In doing this, a_strnlen() looks only at the first \c n
 177  * characters at \c s and never beyond \c s+n.
 178  *
 179  * \param[in]  s    the string.
 180  * \param[in]  n    the maximum length to return.
 181  * \return \c a_strlen(s) if less than \c n, else \c n.
 182  */
 183 static inline ssize_t a_strnlen(const char *s, ssize_t n)
 184 {
 185     if (s)
 186     {
 187         const char *p = memchr(s, '\0', n);
 188         return p ? p - s : n;
 189     }
 190     return 0;
 191 }
 192
 193 /** \brief \c NULL resistant strdup.
 194  *
 195  * the a_strdup() function returns a pointer to a new string, which is a
 196  * duplicate of \c s. Memory should be freed using p_delete().
 197  *
 198  * \warning when s is \c "", it returns NULL !
 199  *
 200  * \param[in] s the string to duplicate.
 201  * \return a pointer to the duplicated string.
 202  */
 203 static inline
 204 char *a_strdup(const char *s)
 205 {
 206     ssize_t len = a_strlen(s);
 207     return len ? p_dup(s, len + 1) : NULL;
 208 }
 209
 210 /** \brief safe limited strdup.
 211  *
 212  * Copies at most min(<tt>n-1</tt>, \c l) characters from \c src into a newly
 213  * allocated buffer, always adding a final \c \\0, and returns that buffer.
 214  *
 215  * \warning when s is \c "" or l is 0, it returns NULL !
 216  *
 217  * \param[in]  s        source string.
 218  * \param[in]  l        maximum number of chars to copy.
 219  * \return a newly allocated buffer containing the first \c l chars of \c src.
 220 */
 221 static inline
 222 char * a_strndup(const char *s, ssize_t l)
 223 {
 224     ssize_t len = MIN(a_strlen(s), l);
 225     if(len)
 226     {
 227         char *p = p_dup(s, len + 1);
 228         p[len] = '\0';
 229         return p;
 230     }
 231     return NULL;
 232 }
 233
 234 /** \brief \c NULL resistant strcmp.
 235  * \param[in]  a     the first string.
 236  * \param[in]  b     the second string.
 237  * \return <tt>strcmp(a, b)</tt>, and treats \c NULL strings like \c ""
 238  * ones.
 239  */
 240 static inline int a_strcmp(const char *a, const char *b)
 241 {
 242     return strcmp(NONULL(a), NONULL(b));
 243 }
 244
 245 /** \brief \c NULL resistant strcasecmp.
 246  * \param[in]  a     the first string.
 247  * \param[in]  b     the second string.
 248  * \return <tt>strcasecmp(a, b)</tt>, and treats \c NULL strings like \c ""
 249  * ones.
 250  */
 251 static inline int a_strcasecmp(const char *a, const char *b)
 252 {
 253     return strcasecmp(NONULL(a), NONULL(b));
 254 }
 255
 256 /** \brief \c NULL resistant strncmp.
 257  * \param[in]  a     the first string.
 258  * \param[in]  b     the second string.
 259  * \param[in]  n     the number of maximum chars to compare.
 260  * \return <tt>strncmp(a, b, n)</tt>, and treats \c NULL strings like \c ""
 261  * ones.
 262  */
 263 static inline int a_strncmp(const char *a, const char *b, ssize_t n)
 264 {
 265     return strncmp(NONULL(a), NONULL(b), n);
 266 }
 267
 268 ssize_t a_strncpy(char *dst, ssize_t n, const char *src, ssize_t l) __attribute__((nonnull(1)));
 269 ssize_t a_strcpy(char *dst, ssize_t n, const char *src) __attribute__((nonnull(1)));
 270
 271 /** \brief safe strcat.
 272  *
 273  * The a_strcat() function appends the string \c src at the end of the buffer
 274  * \c dst if space is available.
 275  *
 276  * \param[in]  dst   destination buffer.
 277  * \param[in]  n     size of the buffer, Negative sizes are allowed.
 278  * \param[in]  src   the string to append.
 279  * \return <tt>a_strlen(dst) + a_strlen(src)</tt>
 280  */
 281 static inline ssize_t a_strcat(char *dst, ssize_t n, const char *src)
 282 {
 283     ssize_t dlen = a_strnlen(dst, n - 1);
 284     return dlen + a_strcpy(dst + dlen, n - dlen, src);
 285 }
 286
 287 /** \brief safe strncat.
 288  *
 289  * The a_strncat() function appends at most \c n chars from the string \c src
 290  * at the end of the buffer \c dst if space is available.
 291  *
 292  * \param[in]  dst   destination buffer.
 293  * \param[in]  n     size of the buffer, Negative sizes are allowed.
 294  * \param[in]  src   the string to append.
 295  * \param[in]  l     maximum number of chars of src to consider.
 296  * \return the smallest value between <tt>a_strlen(dst) + a_strlen(src)</tt>
 297  * and <tt>a_strlen(dst) + l</tt>
 298  */
 299 static inline ssize_t
 300 a_strncat(char *dst, ssize_t n, const char *src, ssize_t l)
 301 {
 302     ssize_t dlen = a_strnlen(dst, n - 1);
 303     return dlen + a_strncpy(dst + dlen, n - dlen, src, l);
 304 }
 305
 306 /** \brief convert a string to a boolean value.
 307  *
 308  * The a_strtobool() function converts a string \c s into a boolean.
 309  * It recognizes the strings "true", "on", "yes" and "1".
 310  *
 311  * \param[in]  s     the string to convert
 312  * \return true if the string is recognized as possibly true, false otherwise.
 313  */
 314 static inline bool
 315 a_strtobool(const char *s, ssize_t len)
 316 {
 317     switch(a_tokenize(s, len))
 318     {
 319         case A_TK_TRUE:
 320         case A_TK_YES:
 321         case A_TK_ON:
 322         case A_TK_1:
 323           return true;
 324         default:
 325           return false;
 326     }
 327 }
 328
 329 #define fatal(string, ...) _fatal(__LINE__, \
 330                                   __FUNCTION__, \
 331                                   string, ## __VA_ARGS__)
 332 void _fatal(int, const char *, const char *, ...)
 333     __attribute__ ((noreturn)) __attribute__ ((format(printf, 3, 4)));
 334
 335 #define warn(string, ...) _warn(__LINE__, \
 336                                 __FUNCTION__, \
 337                                 string, ## __VA_ARGS__)
 338 void _warn(int, const char *, const char *, ...)
 339     __attribute__ ((format(printf, 3, 4)));
 340
 341 position_t position_fromstr(const char *, ssize_t);
 342 const char * position_tostr(position_t);
 343 orientation_t orientation_fromstr(const char *, ssize_t);
 344 const char * orientation_tostr(orientation_t);
 345 void *name_func_lookup(const char *, const name_func_link_t *);
 346 const char * name_func_rlookup(void *, const name_func_link_t *);
 347 void a_exec(const char *);
 348 char ** a_strsplit(const char *, ssize_t, char);
 349
 350 #endif
 351 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=80