common/cmd_itest.c

   1 /*
   2  * (C) Copyright 2003
   3  * Tait Electronics Limited, Christchurch, New Zealand
   4  *
   5  * See file CREDITS for list of people who contributed to this
   6  * project.
   7  *
   8  * This program is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU General Public License as
  10  * published by the Free Software Foundation; either version 2 of
  11  * the License, or (at your option) any later version.
  12  *
  13  * This program is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16  * GNU General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU General Public License
  19  * along with this program; if not, write to the Free Software
  20  * Foundation, Inc., 59 Temple Place, Suite 330, Boston,
  21  * MA 02111-1307 USA
  22  */
  23
  24 /*
  25  * This file provides a shell like 'test' function to return
  26  * true/false from an integer or string compare of two memory
  27  * locations or a location and a scalar/literal.
  28  * A few parts were lifted from bash 'test' command
  29  */
  30
  31 #include <common.h>
  32 #include <config.h>
  33 #include <command.h>
  34
  35 #if (CONFIG_COMMANDS & CFG_CMD_ITEST)
  36
  37 #define EQ      0
  38 #define NE      1
  39 #define LT      2
  40 #define GT      3
  41 #define LE      4
  42 #define GE      5
  43
  44 struct op_tbl_s {
  45         char    *op;            /* operator string */
  46         int     opcode;         /* internal representation of opcode */
  47 };
  48
  49 typedef struct op_tbl_s op_tbl_t;
  50
  51 op_tbl_t op_table [] = {
  52         { "-lt", LT },
  53         { "<"  , LT },
  54         { "-gt", GT },
  55         { ">"  , GT },
  56         { "-eq", EQ },
  57         { "==" , EQ },
  58         { "-ne", NE },
  59         { "!=" , NE },
  60         { "<>" , NE },
  61         { "-ge", GE },
  62         { ">=" , GE },
  63         { "-le", LE },
  64         { "<=" , LE },
  65 };
  66
  67 #define op_tbl_size (sizeof(op_table)/sizeof(op_table[0]))
  68
  69 extern int cmd_get_data_size(char* arg, int default_size);
  70
  71 static long evalexp(char *s, int w)
  72 {
  73         long l, *p;
  74
  75         /* if the parameter starts with a * then assume is a pointer to the value we want */
  76         if (s[0] == '*') {
  77                 p = (long *)simple_strtoul(&s[1], NULL, 16);
  78                 l = *p;
  79         } else {
  80                 l = simple_strtoul(s, NULL, 16);
  81         }
  82
  83         return (l & ((1 << (w * 8)) - 1));
  84 }
  85
  86 static char * evalstr(char *s)
  87 {
  88         /* if the parameter starts with a * then assume a string pointer else its a literal */
  89         if (s[0] == '*') {
  90                 return (char *)simple_strtoul(&s[1], NULL, 16);
  91         } else {
  92                 return s;
  93         }
  94 }
  95
  96 static int stringcomp(char *s, char *t, int op)
  97 {
  98         int n, p;
  99         char *l, *r;
 100
 101         l = evalstr(s);
 102         r = evalstr(t);
 103
 104         /* we'll do a compare based on the length of the shortest string */
 105         n = min(strlen(l), strlen(r));
 106
 107         p = strncmp(l, r, n);
 108         switch (op) {
 109         case EQ: return (p == 0);
 110         case NE: return (p != 0);
 111         case LT: return (p < 0);
 112         case GT: return (p > 0);
 113         case LE: return (p <= 0);
 114         case GE: return (p >= 0);
 115         }
 116         return (0);
 117 }
 118
 119 static int arithcomp (char *s, char *t, int op, int w)
 120 {
 121         long l, r;
 122
 123         l = evalexp (s, w);
 124         r = evalexp (t, w);
 125
 126         switch (op) {
 127         case EQ: return (l == r);
 128         case NE: return (l != r);
 129         case LT: return (l < r);
 130         case GT: return (l > r);
 131         case LE: return (l <= r);
 132         case GE: return (l >= r);
 133         }
 134         return (0);
 135 }
 136
 137 int binary_test (char *op, char *arg1, char *arg2, int w)
 138 {
 139         int len, i;
 140         op_tbl_t *optp;
 141
 142         len = strlen(op);
 143
 144         for (optp = (op_tbl_t *)&op_table, i = 0;
 145              i < op_tbl_size;
 146              optp++, i++) {
 147
 148                 if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
 149                         if (w == 0) {
 150                                 return (stringcomp(arg1, arg2, optp->opcode));
 151                         } else {
 152                                 return (arithcomp (arg1, arg2, optp->opcode, w));
 153                         }
 154                 }
 155         }
 156
 157         printf("Unknown operator '%s'\n", op);
 158         return 0;       /* op code not found */
 159 }
 160
 161 /* command line interface to the shell test */
 162 int do_itest ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[] )
 163 {
 164         int     value, w;
 165
 166         /* Validate arguments */
 167         if ((argc != 4)){
 168                 printf("Usage:\n%s\n", cmdtp->usage);
 169                 return 1;
 170         }
 171
 172         /* Check for a data width specification.
 173          * Defaults to long (4) if no specification.
 174          * Uses -2 as 'width' for .s (string) so as not to upset existing code
 175          */
 176         switch (w = cmd_get_data_size(argv[0], 4)) {
 177         case 1:
 178         case 2:
 179         case 4:
 180                 value = binary_test (argv[2], argv[1], argv[3], w);
 181                 break;
 182         case -2:
 183                 value = binary_test (argv[2], argv[1], argv[3], 0);
 184                 break;
 185         case -1:
 186         default:
 187                 puts("Invalid data width specifier\n");
 188                 value = 0;
 189                 break;
 190         }
 191
 192         return !value;
 193 }
 194
 195 U_BOOT_CMD(
 196         itest, 4, 0, do_itest,
 197         "itest\t- return true/false on integer compare\n",
 198         "[.b, .w, .l, .s] [*]value1 <op> [*]value2\n"
 199 );
 200 #endif  /* CONFIG_COMMANDS & CFG_CMD_ITEST */