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 "common.h"
  29
  30 /** Link a name to a function */
  31 typedef struct
  32 {
  33     const char *name;
  34     void *func;
  35 } NameFuncLink;
  36
  37 /** \brief replace \c NULL strings with emtpy strings */
  38 #define NONULL(x)       (x ? x : "")
  39
  40 #undef MAX
  41 #undef MIN
  42 #define MAX(a,b) ((a) < (b) ? (b) : (a))
  43 #define MIN(a,b) ((a) < (b) ? (a) : (b))
  44
  45 #define ssizeof(foo)            (ssize_t)sizeof(foo)
  46 #define countof(foo)            (ssizeof(foo) / ssizeof(foo[0]))
  47
  48 #define p_new(type, count)      ((type *)xmalloc(sizeof(type) * (count)))
  49 #define p_clear(p, count)       ((void)memset((p), 0, sizeof(*(p)) * (count)))
  50 #define p_realloc(pp, count)    xrealloc((void*)(pp), sizeof(**(pp)) * (count))
  51 #define p_dup(p, count)         xmemdup((p), sizeof(*(p)) * (count))
  52
  53 #ifdef __GNUC__
  54
  55 #define p_delete(mem_pp)                           \
  56     do {                                           \
  57         typeof(**(mem_pp)) **__ptr = (mem_pp);     \
  58         free(*__ptr);                              \
  59         *__ptr = NULL;                             \
  60     } while(0)
  61
  62 #else
  63
  64 #define p_delete(mem_p)                            \
  65     do {                                           \
  66         void *__ptr = (mem_p);                     \
  67         free(*__ptr);                              \
  68         *(void **)__ptr = NULL;                    \
  69     } while (0)
  70
  71 #endif
  72
  73 static inline void * __attribute__ ((malloc)) xmalloc(ssize_t size)
  74 {
  75     void *ptr;
  76
  77     if(size <= 0)
  78         return NULL;
  79
  80     ptr = calloc(1, size);
  81
  82     if(!ptr)
  83         abort();
  84
  85     return ptr;
  86 }
  87
  88 static inline void
  89 xrealloc(void **ptr, ssize_t newsize)
  90 {
  91     if(newsize <= 0)
  92         p_delete(ptr);
  93     else
  94     {
  95         *ptr = realloc(*ptr, newsize);
  96         if(!*ptr)
  97             abort();
  98     }
  99 }
 100
 101 static inline void *xmemdup(const void *src, ssize_t size)
 102 {
 103     return memcpy(xmalloc(size), src, size);
 104 }
 105
 106 /** \brief \c NULL resistant strlen.
 107  *
 108  * Unlinke it's libc sibling, a_strlen returns a ssize_t, and supports its
 109  * argument beeing NULL.
 110  *
 111  * \param[in] s the string.
 112  * \return the string length (or 0 if \c s is \c NULL).
 113  */
 114 static inline ssize_t a_strlen(const char *s)
 115 {
 116     return s ? strlen(s) : 0;
 117 }
 118
 119 /** \brief \c NULL resistant strnlen.
 120  *
 121  * Unlinke it's GNU libc sibling, a_strnlen returns a ssize_t, and supports
 122  * its argument beeing NULL.
 123  *
 124  * The a_strnlen() function returns the number of characters in the string
 125  * pointed to by \c s, not including the terminating \c \\0 character, but at
 126  * most \c n. In doing this, a_strnlen() looks only at the first \c n
 127  * characters at \c s and never beyond \c s+n.
 128  *
 129  * \param[in]  s    the string.
 130  * \param[in]  n    the maximum length to return.
 131  * \return \c a_strlen(s) if less than \c n, else \c n.
 132  */
 133 static inline ssize_t a_strnlen(const char *s, ssize_t n)
 134 {
 135     if (s)
 136     {
 137         const char *p = memchr(s, '\0', n);
 138         return p ? p - s : n;
 139     }
 140     return 0;
 141 }
 142
 143 /** \brief \c NULL resistant strdup.
 144  *
 145  * the a_strdup() function returns a pointer to a new string, which is a
 146  * duplicate of \c s. Memory should be freed using p_delete().
 147  *
 148  * \warning when s is \c "", it returns NULL !
 149  *
 150  * \param[in] s the string to duplicate.
 151  * \return a pointer to the duplicated string.
 152  */
 153 static inline char *a_strdup(const char *s)
 154 {
 155     ssize_t len = a_strlen(s);
 156     return len ? p_dup(s, len + 1) : NULL;
 157 }
 158
 159 /** \brief \c NULL resistant strcmp.
 160  * \param[in]  a     the first string.
 161  * \param[in]  b     the second string.
 162  * \return <tt>strcmp(a, b)</tt>, and treats \c NULL strings like \c ""
 163  * ones.
 164  */
 165 static inline int a_strcmp(const char *a, const char *b)
 166 {
 167         return strcmp(NONULL(a), NONULL(b));
 168 }
 169
 170 /** \brief \c NULL resistant strncmp.
 171  * \param[in]  a     the first string.
 172  * \param[in]  b     the second string.
 173  * \param[in]  n     the number of maximum chars to compare.
 174  * \return <tt>strncmp(a, b, n)</tt>, and treats \c NULL strings like \c ""
 175  * ones.
 176  */
 177 static inline int a_strncmp(const char *a, const char *b, ssize_t n)
 178 {
 179     return strncmp(NONULL(a), NONULL(b), n);
 180 }
 181
 182 ssize_t a_strncpy(char *dst, ssize_t n, const char *src, ssize_t l) __attribute__((nonnull(1)));
 183 ssize_t a_strcpy(char *dst, ssize_t n, const char *src) __attribute__((nonnull(1)));
 184
 185 /** \brief safe strcat.
 186  *
 187  * The a_strcat() function appends the string \c src at the end of the buffer
 188  * \c dst if space is available.
 189  *
 190  * \param[in]  dst   destination buffer.
 191  * \param[in]  n     size of the buffer, Negative sizes are allowed.
 192  * \param[in]  src   the string to append.
 193  * \return <tt>a_strlen(dst) + a_strlen(src)</tt>
 194  */
 195 static inline ssize_t a_strcat(char *dst, ssize_t n, const char *src)
 196 {
 197     ssize_t dlen = a_strnlen(dst, n - 1);
 198     return dlen + a_strcpy(dst + dlen, n - dlen, src);
 199 }
 200
 201 void die(const char *, ...) __attribute__ ((noreturn)) __attribute__ ((format(printf, 1, 2)));
 202 void eprint(const char *, ...) __attribute__ ((noreturn)) __attribute__ ((format(printf, 1, 2)));
 203 Bool xgettextprop(Display *, Window, Atom, char *, ssize_t);
 204 double compute_new_value_from_arg(const char *, double);
 205 void *name_func_lookup(const char *, const NameFuncLink *);
 206
 207 UICB_PROTO(uicb_spawn);
 208 UICB_PROTO(uicb_exec);
 209 #endif
 210 // vim: filetype=c:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:encoding=utf-8:textwidth=99