util.h

   1 /*
   2  * util.c - useful functions header
   3  *
   4  * Copyright © 2007 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_MEM_H
  24 #define AWESOME_MEM_H
  25
  26 #include <string.h>
  27 #include <stdlib.h>
  28 #include "config.h"
  29
  30 /** \brief replace \c NULL strings with emtpy strings */
  31 #define NONULL(x)       (x ? x : "")
  32
  33 #define ssizeof(foo)            (ssize_t)sizeof(foo)
  34 #define countof(foo)            (ssizeof(foo) / ssizeof(foo[0]))
  35
  36 #define p_new(type, count)      ((type *)xmalloc(sizeof(type) * (count)))
  37 #define p_clear(p, count)       ((void)memset((p), 0, sizeof(*(p)) * (count)))
  38 #define p_realloc(pp, count)    xrealloc((void*)(pp), sizeof(**(pp)) * (count))
  39 #define p_dup(p, count)         xmemdup((p), sizeof(*(p)) * (count))
  40
  41 #ifdef __GNUC__
  42
  43 #define p_delete(mem_pp)                           \
  44     do {                                           \
  45         typeof(**(mem_pp)) **__ptr = (mem_pp);     \
  46         free(*__ptr);                              \
  47         *__ptr = NULL;                             \
  48     } while(0)
  49
  50 #else
  51
  52 #define p_delete(mem_p)                            \
  53     do {                                           \
  54         void *__ptr = (mem_p);                     \
  55         free(*__ptr);                              \
  56         *(void **)__ptr = NULL;                    \
  57     } while (0)
  58
  59 #endif
  60
  61 static inline void * __attribute__ ((malloc)) xmalloc(ssize_t size)
  62 {
  63     void *ptr;
  64
  65     if(size <= 0)
  66         return NULL;
  67
  68     ptr = calloc(1, size);
  69
  70     if(!ptr)
  71         abort();
  72
  73     return ptr;
  74 }
  75
  76 static inline void
  77 xrealloc(void **ptr, ssize_t newsize)
  78 {
  79     if(newsize <= 0)
  80         p_delete(ptr);
  81     else
  82     {
  83         *ptr = realloc(*ptr, newsize);
  84         if(!*ptr)
  85             abort();
  86     }
  87 }
  88
  89 static inline void *xmemdup(const void *src, ssize_t size)
  90 {
  91     return memcpy(xmalloc(size), src, size);
  92 }
  93
  94 /** \brief \c NULL resistant strlen.
  95  *
  96  * Unlinke it's libc sibling, a_strlen returns a ssize_t, and supports its
  97  * argument beeing NULL.
  98  *
  99  * \param[in] s the string.
 100  * \return the string length (or 0 if \c s is \c NULL).
 101  */
 102 static inline ssize_t a_strlen(const char *s)
 103 {
 104     return s ? strlen(s) : 0;
 105 }
 106
 107
 108 /** \brief \c NULL resistant strdup.
 109  *
 110  * the a_strdup() function returns a pointer to a new string, which is a
 111  * duplicate of \c s. Memory should be freed using p_delete().
 112  *
 113  * \warning when s is \c "", it returns NULL !
 114  *
 115  * \param[in] s the string to duplicate.
 116  * \return a pointer to the duplicated string.
 117  */
 118 static inline char *a_strdup(const char *s)
 119 {
 120     ssize_t len = a_strlen(s);
 121     return len ? p_dup(s, len + 1) : NULL;
 122 }
 123
 124 /** \brief \c NULL resistant strcmp.
 125  * \param[in]  a     the first string.
 126  * \param[in]  b     the second string.
 127  * \return <tt>strcmp(a, b)</tt>, and treats \c NULL strings like \c ""
 128  * ones.
 129  */
 130 static inline int a_strcmp(const char *a, const char *b)
 131 {
 132         return strcmp(NONULL(a), NONULL(b));
 133 }
 134
 135 void die(const char *, ...) __attribute__ ((noreturn)) __attribute__ ((format(printf, 1, 2)));
 136 void eprint(const char *, ...) __attribute__ ((noreturn)) __attribute__ ((format(printf, 1, 2)));
 137 void uicb_spawn(Display *, DC *, awesome_config *, const char *);
 138 Bool xgettextprop(Display *, Window, Atom, char *, unsigned int);
 139 double compute_new_value_from_arg(const char *, double);
 140
 141 #endif