nasmlib/string.c

   1 /* ----------------------------------------------------------------------- *
   2  *
   3  *   Copyright 1996-2016 The NASM Authors - All Rights Reserved
   4  *   See the file AUTHORS included with the NASM distribution for
   5  *   the specific copyright holders.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following
   9  *   conditions are met:
  10  *
  11  *   * Redistributions of source code must retain the above copyright
  12  *     notice, this list of conditions and the following disclaimer.
  13  *   * Redistributions in binary form must reproduce the above
  14  *     copyright notice, this list of conditions and the following
  15  *     disclaimer in the documentation and/or other materials provided
  16  *     with the distribution.
  17  *
  18  *     THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
  19  *     CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
  20  *     INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
  21  *     MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
  22  *     DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
  23  *     CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  24  *     SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  25  *     NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
  26  *     LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  27  *     HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  28  *     CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  29  *     OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
  30  *     EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  31  *
  32  * ----------------------------------------------------------------------- */
  33
  34 /*
  35  * nasmlib.c    library routines for the Netwide Assembler
  36  */
  37
  38 #include "compiler.h"
  39 #include "nasmlib.h"
  40 #include "nctype.h"
  41
  42 #ifndef nasm_stricmp
  43 int nasm_stricmp(const char *s1, const char *s2)
  44 {
  45     unsigned char c1, c2;
  46     int d;
  47
  48     while (1) {
  49         c1 = nasm_tolower(*s1++);
  50         c2 = nasm_tolower(*s2++);
  51         d = c1-c2;
  52
  53         if (d)
  54             return d;
  55         if (!c1)
  56             break;
  57     }
  58     return 0;
  59 }
  60 #endif
  61
  62 #ifndef nasm_strnicmp
  63 int nasm_strnicmp(const char *s1, const char *s2, size_t n)
  64 {
  65     unsigned char c1, c2;
  66     int d;
  67
  68     while (n--) {
  69         c1 = nasm_tolower(*s1++);
  70         c2 = nasm_tolower(*s2++);
  71         d = c1-c2;
  72
  73         if (d)
  74             return d;
  75         if (!c1)
  76             break;
  77     }
  78     return 0;
  79 }
  80 #endif
  81
  82 int nasm_memicmp(const char *s1, const char *s2, size_t n)
  83 {
  84     unsigned char c1, c2;
  85     int d;
  86
  87     while (n--) {
  88         c1 = nasm_tolower(*s1++);
  89         c2 = nasm_tolower(*s2++);
  90         d = c1-c2;
  91         if (d)
  92             return d;
  93     }
  94     return 0;
  95 }
  96
  97 #ifndef nasm_strsep
  98 char *nasm_strsep(char **stringp, const char *delim)
  99 {
 100         char *s = *stringp;
 101         char *e;
 102
 103         if (!s)
 104                 return NULL;
 105
 106         e = strpbrk(s, delim);
 107         if (e)
 108                 *e++ = '\0';
 109
 110         *stringp = e;
 111         return s;
 112 }
 113 #endif
 114
 115 /* skip leading spaces */
 116 char *nasm_skip_spaces(const char *p)
 117 {
 118     if (p)
 119         while (*p && nasm_isspace(*p))
 120             p++;
 121     return (char *)p;
 122 }
 123
 124 /* skip leading non-spaces */
 125 char *nasm_skip_word(const char *p)
 126 {
 127     if (p)
 128         while (*p && !nasm_isspace(*p))
 129             p++;
 130     return (char *)p;
 131 }
 132
 133 /* zap leading spaces with zero */
 134 char *nasm_zap_spaces_fwd(char *p)
 135 {
 136     if (p)
 137         while (*p && nasm_isspace(*p))
 138             *p++ = 0x0;
 139     return p;
 140 }
 141
 142 /* zap spaces with zero in reverse order */
 143 char *nasm_zap_spaces_rev(char *p)
 144 {
 145     if (p)
 146         while (*p && nasm_isspace(*p))
 147             *p-- = 0x0;
 148     return p;
 149 }
 150
 151 /* zap leading and trailing spaces */
 152 char *nasm_trim_spaces(char *p)
 153 {
 154     p = nasm_zap_spaces_fwd(p);
 155     nasm_zap_spaces_fwd(nasm_skip_word(p));
 156
 157     return p;
 158 }
 159
 160 /*
 161  * return the word extracted from a stream
 162  * or NULL if nothing left
 163  */
 164 char *nasm_get_word(char *p, char **tail)
 165 {
 166     char *word = nasm_skip_spaces(p);
 167     char *next = nasm_skip_word(word);
 168
 169     if (word && *word) {
 170         if (*next)
 171             *next++ = '\0';
 172     } else
 173         word = next = NULL;
 174
 175     /* NOTE: the tail may start with spaces */
 176     *tail = next;
 177
 178     return word;
 179 }
 180
 181 /*
 182  * Extract "opt=val" values from the stream and
 183  * returns "opt"
 184  *
 185  * Exceptions:
 186  * 1) If "=val" passed the NULL returned though
 187  *    you may continue handling the tail via "next"
 188  * 2) If "=" passed the NULL is returned and "val"
 189  *    is set to NULL as well
 190  */
 191 char *nasm_opt_val(char *p, char **val, char **next)
 192 {
 193     char *q, *nxt;
 194
 195     *val = *next = NULL;
 196
 197     p = nasm_get_word(p, &nxt);
 198     if (!p)
 199         return NULL;
 200
 201     q = strchr(p, '=');
 202     if (q) {
 203         if (q == p)
 204             p = NULL;
 205         *q++='\0';
 206         if (*q) {
 207             *val = q;
 208         } else {
 209             q = nasm_get_word(q + 1, &nxt);
 210             if (q)
 211                 *val = q;
 212         }
 213     } else {
 214         q = nasm_skip_spaces(nxt);
 215         if (q && *q == '=') {
 216             q = nasm_get_word(q + 1, &nxt);
 217             if (q)
 218                 *val = q;
 219         }
 220     }
 221
 222     *next = nxt;
 223     return p;
 224 }