gpxe/src/core/string.c

   1 /*
   2  *  Copyright (C) 1991, 1992  Linus Torvalds
   3  *  Copyright (C) 2004 Tobias Lorenz
   4  *
   5  *  string handling functions
   6  *  based on linux/lib/string.c
   7  *
   8  * This program is free software; you can redistribute it and/or modify
   9  * it under the terms of the GNU General Public License version 2 as
  10  * published by the Free Software Foundation.
  11  */
  12
  13 /*
  14  * stupid library routines.. The optimized versions should generally be found
  15  * as inline code in <asm-xx/string.h>
  16  *
  17  * These are buggy as well..
  18  *
  19  * * Fri Jun 25 1999, Ingo Oeser <ioe@informatik.tu-chemnitz.de>
  20  * -  Added strsep() which will replace strtok() soon (because strsep() is
  21  *    reentrant and should be faster). Use only strsep() in new code, please.
  22  */
  23
  24 #include <stdint.h>
  25 #include <stdlib.h>
  26 #include <string.h>
  27 #include <ctype.h>
  28
  29 /* *** FROM string.c *** */
  30
  31 #ifndef __HAVE_ARCH_STRCPY
  32 /**
  33  * strcpy - Copy a %NUL terminated string
  34  * @dest: Where to copy the string to
  35  * @src: Where to copy the string from
  36  */
  37 char * strcpy(char * dest,const char *src)
  38 {
  39         char *tmp = dest;
  40
  41         while ((*dest++ = *src++) != '\0')
  42                 /* nothing */;
  43         return tmp;
  44 }
  45 #endif
  46
  47 #ifndef __HAVE_ARCH_STRNCPY
  48 /**
  49  * strncpy - Copy a length-limited, %NUL-terminated string
  50  * @dest: Where to copy the string to
  51  * @src: Where to copy the string from
  52  * @count: The maximum number of bytes to copy
  53  *
  54  * Note that unlike userspace strncpy, this does not %NUL-pad the buffer.
  55  * However, the result is not %NUL-terminated if the source exceeds
  56  * @count bytes.
  57  */
  58 char * strncpy(char * dest,const char *src,size_t count)
  59 {
  60         char *tmp = dest;
  61
  62         while (count-- && (*dest++ = *src++) != '\0')
  63                 /* nothing */;
  64
  65         return tmp;
  66 }
  67 #endif
  68
  69 #ifndef __HAVE_ARCH_STRCAT
  70 /**
  71  * strcat - Append one %NUL-terminated string to another
  72  * @dest: The string to be appended to
  73  * @src: The string to append to it
  74  */
  75 char * strcat(char * dest, const char * src)
  76 {
  77         char *tmp = dest;
  78
  79         while (*dest)
  80                 dest++;
  81         while ((*dest++ = *src++) != '\0')
  82                 ;
  83
  84         return tmp;
  85 }
  86 #endif
  87
  88 #ifndef __HAVE_ARCH_STRCMP
  89 /**
  90  * strcmp - Compare two strings
  91  * @cs: One string
  92  * @ct: Another string
  93  */
  94 int strcmp(const char * cs,const char * ct)
  95 {
  96         register signed char __res;
  97
  98         while (1) {
  99                 if ((__res = *cs - *ct++) != 0 || !*cs++)
 100                         break;
 101         }
 102
 103         return __res;
 104 }
 105 #endif
 106
 107 #ifndef __HAVE_ARCH_STRNCMP
 108 /**
 109  * strncmp - Compare two length-limited strings
 110  * @cs: One string
 111  * @ct: Another string
 112  * @count: The maximum number of bytes to compare
 113  */
 114 int strncmp(const char * cs,const char * ct,size_t count)
 115 {
 116         register signed char __res = 0;
 117
 118         while (count) {
 119                 if ((__res = *cs - *ct++) != 0 || !*cs++)
 120                         break;
 121                 count--;
 122         }
 123
 124         return __res;
 125 }
 126 #endif
 127
 128 #ifndef __HAVE_ARCH_STRCASECMP
 129 int strcasecmp(const char *a, const char *b)
 130 {
 131         while (*a && *b && (*a & ~0x20) == (*b & ~0x20)) {a++; b++; }
 132         return((*a & ~0x20) - (*b & ~0x20));
 133 }
 134 #endif
 135
 136 #ifndef __HAVE_ARCH_STRCHR
 137 /**
 138  * strchr - Find the first occurrence of a character in a string
 139  * @s: The string to be searched
 140  * @c: The character to search for
 141  */
 142 char * strchr(const char * s, int c)
 143 {
 144         for(; *s != (char) c; ++s)
 145                 if (*s == '\0')
 146                         return NULL;
 147         return (char *) s;
 148 }
 149 #endif
 150
 151 #ifndef __HAVE_ARCH_STRRCHR
 152 /**
 153  * strrchr - Find the last occurrence of a character in a string
 154  * @s: The string to be searched
 155  * @c: The character to search for
 156  */
 157 char * strrchr(const char * s, int c)
 158 {
 159        const char *p = s + strlen(s);
 160        do {
 161            if (*p == (char)c)
 162                return (char *)p;
 163        } while (--p >= s);
 164        return NULL;
 165 }
 166 #endif
 167
 168 #ifndef __HAVE_ARCH_STRLEN
 169 /**
 170  * strlen - Find the length of a string
 171  * @s: The string to be sized
 172  */
 173 size_t strlen(const char * s)
 174 {
 175         const char *sc;
 176
 177         for (sc = s; *sc != '\0'; ++sc)
 178                 /* nothing */;
 179         return sc - s;
 180 }
 181 #endif
 182
 183 #ifndef __HAVE_ARCH_STRNLEN
 184 /**
 185  * strnlen - Find the length of a length-limited string
 186  * @s: The string to be sized
 187  * @count: The maximum number of bytes to search
 188  */
 189 size_t strnlen(const char * s, size_t count)
 190 {
 191         const char *sc;
 192
 193         for (sc = s; count-- && *sc != '\0'; ++sc)
 194                 /* nothing */;
 195         return sc - s;
 196 }
 197 #endif
 198
 199 #ifndef __HAVE_ARCH_MEMSET
 200 /**
 201  * memset - Fill a region of memory with the given value
 202  * @s: Pointer to the start of the area.
 203  * @c: The byte to fill the area with
 204  * @count: The size of the area.
 205  *
 206  * Do not use memset() to access IO space, use memset_io() instead.
 207  */
 208 void * memset(void * s,int c,size_t count)
 209 {
 210         char *xs = (char *) s;
 211
 212         while (count--)
 213                 *xs++ = c;
 214
 215         return s;
 216 }
 217 #endif
 218
 219 #ifndef __HAVE_ARCH_MEMCPY
 220 /**
 221  * memcpy - Copy one area of memory to another
 222  * @dest: Where to copy to
 223  * @src: Where to copy from
 224  * @count: The size of the area.
 225  *
 226  * You should not use this function to access IO space, use memcpy_toio()
 227  * or memcpy_fromio() instead.
 228  */
 229 void * memcpy(void * dest,const void *src,size_t count)
 230 {
 231         char *tmp = (char *) dest, *s = (char *) src;
 232
 233         while (count--)
 234                 *tmp++ = *s++;
 235
 236         return dest;
 237 }
 238 #endif
 239
 240 #ifndef __HAVE_ARCH_MEMMOVE
 241 /**
 242  * memmove - Copy one area of memory to another
 243  * @dest: Where to copy to
 244  * @src: Where to copy from
 245  * @count: The size of the area.
 246  *
 247  * Unlike memcpy(), memmove() copes with overlapping areas.
 248  */
 249 void * memmove(void * dest,const void *src,size_t count)
 250 {
 251         char *tmp, *s;
 252
 253         if (dest <= src) {
 254                 tmp = (char *) dest;
 255                 s = (char *) src;
 256                 while (count--)
 257                         *tmp++ = *s++;
 258                 }
 259         else {
 260                 tmp = (char *) dest + count;
 261                 s = (char *) src + count;
 262                 while (count--)
 263                         *--tmp = *--s;
 264                 }
 265
 266         return dest;
 267 }
 268 #endif
 269
 270 #ifndef __HAVE_ARCH_MEMCMP
 271 /**
 272  * memcmp - Compare two areas of memory
 273  * @cs: One area of memory
 274  * @ct: Another area of memory
 275  * @count: The size of the area.
 276  */
 277 int memcmp(const void * cs,const void * ct,size_t count)
 278 {
 279         const unsigned char *su1, *su2;
 280         int res = 0;
 281
 282         for( su1 = cs, su2 = ct; 0 < count; ++su1, ++su2, count--)
 283                 if ((res = *su1 - *su2) != 0)
 284                         break;
 285         return res;
 286 }
 287 #endif
 288
 289 #ifndef __HAVE_ARCH_STRSTR
 290 /**
 291  * strstr - Find the first substring in a %NUL terminated string
 292  * @s1: The string to be searched
 293  * @s2: The string to search for
 294  */
 295 char * strstr(const char * s1,const char * s2)
 296 {
 297         int l1, l2;
 298
 299         l2 = strlen(s2);
 300         if (!l2)
 301                 return (char *) s1;
 302         l1 = strlen(s1);
 303         while (l1 >= l2) {
 304                 l1--;
 305                 if (!memcmp(s1,s2,l2))
 306                         return (char *) s1;
 307                 s1++;
 308         }
 309         return NULL;
 310 }
 311 #endif
 312
 313 #ifndef __HAVE_ARCH_MEMCHR
 314 /**
 315  * memchr - Find a character in an area of memory.
 316  * @s: The memory area
 317  * @c: The byte to search for
 318  * @n: The size of the area.
 319  *
 320  * returns the address of the first occurrence of @c, or %NULL
 321  * if @c is not found
 322  */
 323 void * memchr(const void *s, int c, size_t n)
 324 {
 325         const unsigned char *p = s;
 326         while (n-- != 0) {
 327                 if ((unsigned char)c == *p++) {
 328                         return (void *)(p-1);
 329                 }
 330         }
 331         return NULL;
 332 }
 333
 334 #endif
 335
 336 char * strndup(const char *s, size_t n)
 337 {
 338         size_t len = strlen(s);
 339         char *new;
 340
 341         if (len>n)
 342                 len = n;
 343         new = malloc(len+1);
 344         if (new) {
 345                 new[len] = '\0';
 346                 memcpy(new,s,len);
 347         }
 348         return new;
 349 }
 350
 351 char * strdup(const char *s) {
 352         return strndup(s, ~((size_t)0));
 353 }