misc.c

   1 /* hexedit -- Hexadecimal Editor for Binary Files
   2    Copyright (C) 1998 Pixel (Pascal Rigaux)
   3
   4    This program is free software; you can redistribute it and/or modify
   5    it under the terms of the GNU General Public License as published by
   6    the Free Software Foundation; either version 2, or (at your option)
   7    any later version.
   8
   9    This program is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12    GNU General Public License for more details.
  13
  14    You should have received a copy of the GNU General Public License
  15    along with this program; if not, write to the Free Software
  16    Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.*/
  17 #include "hexedit.h"
  18
  19
  20 int LSEEK_(int fd, off_t where)
  21 {
  22   off_t result;
  23
  24   result = lseek(fd, where, SEEK_SET);
  25   return (result == where) ? 1 : -1;
  26 }
  27
  28 void LSEEK(int fd, off_t where)
  29 {
  30   off_t result;
  31
  32   result = lseek(fd, where, SEEK_SET);
  33   if (result != where) {
  34     exitCurses();
  35     fprintf(stderr, "the long seek failed (%lld instead of %lld), leaving :(\n", (long long) result, (long long) where);
  36     exit(1);
  37   }
  38 }
  39
  40 /*******************************************************************************/
  41 /* Small common functions */
  42 /*******************************************************************************/
  43 int streq(const char *s1, const char *s2) { return strcmp(s1, s2) == 0; }
  44 off_t myfloor(off_t a, off_t b) { return a - a % b; }
  45 int setLowBits(int p, int val) { return (p & 0xF0) + val; }
  46 int setHighBits(int p, int val) { return (p & 0x0F) + val * 0x10; }
  47
  48 int strbeginswith(const char *a, const char *prefix)
  49 {
  50   return strncmp(a, prefix, strlen(prefix)) == 0;
  51 }
  52
  53 char *strconcat3(char *a, char *b, char *c)
  54 {
  55   size_t la = a ? strlen(a) : 0;
  56   size_t lb = b ? strlen(b) : 0;
  57   size_t lc = c ? strlen(c) : 0;
  58   char *p = malloc(la + lb + lc + 1);
  59   if (a) memcpy(p, a, la);
  60   if (b) memcpy(p + la, b, lb);
  61   if (c) memcpy(p + la + lb, c, lc);
  62   p[la + lb + lc] = '\0';
  63   return p;
  64 }
  65
  66 int hexCharToInt(int c)
  67 {
  68   if (isdigit(c)) return c - '0';
  69   return tolower(c) - 'a' + 10;
  70 }
  71
  72 int not(int b) { return b ? FALSE: TRUE; }
  73
  74 #ifndef HAVE_MEMRCHR
  75 void *memrchr(const void *s, int c, size_t n)
  76 {
  77   ssize_t i;
  78   const char *cs = s;
  79   for (i = n - 1; i >= 0; i--) if (cs[i] == c) return (void *) &cs[i];
  80   return NULL;
  81 }
  82 #endif
  83
  84 #ifndef HAVE_MEMMEM
  85 char *mymemmem(char *a, size_t sizea, char *b, size_t sizeb)
  86 {
  87   char *p;
  88   ssize_t i = sizea - sizeb + 1;
  89   if (i < 0) return 0;
  90   for (; (p = memchr(a, b[0], i)); i -= p - a + 1, a = p + 1)
  91   {
  92     if ((memcmp(p + 1, b + 1, sizeb - 1)) == 0) {
  93          return p;
  94     }
  95   }
  96   return NULL;
  97 }
  98 #endif
  99
 100 #ifndef HAVE_MEMRMEM
 101 char *mymemrmem(char *a, size_t sizea, char *b, size_t sizeb)
 102 {
 103   char *p;
 104   ssize_t i = sizea - sizeb + 1;
 105   if (i < 0) return 0;
 106
 107   a += sizea - 1;
 108   for (; (p = memrchr(a - i + 1, b[sizeb - 1], i)); i -= a - p + 1, a = p - 1)
 109   {
 110     if ((memcmp(p - sizeb + 1, b, sizeb - 1)) == 0) return p;
 111   }
 112   return NULL;
 113 }
 114 #endif
 115
 116
 117 int hexStringToBinString(char *p, size_t *l)
 118 {
 119   size_t i;
 120
 121   for (i = 0; i < *l; i++) {
 122     if (!isxdigit(p[i])) {
 123       displayMessageAndWaitForKey("Invalid hexa string");
 124       return FALSE;
 125     }
 126     p[i / 2] = ((i % 2) ? setLowBits : setHighBits)(p[i / 2], hexCharToInt(p[i]));
 127   }
 128
 129   if ((*l % 2)) {
 130     displayMessageAndWaitForKey("Must be an even number of chars");
 131     return FALSE;
 132   }
 133   *l /= 2;
 134   return TRUE;
 135 }
 136