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 #define EQ      0
  36 #define NE      1
  37 #define LT      2
  38 #define GT      3
  39 #define LE      4
  40 #define GE      5
  41
  42 struct op_tbl_s {
  43         char    *op;            /* operator string */
  44         int     opcode;         /* internal representation of opcode */
  45 };
  46
  47 typedef struct op_tbl_s op_tbl_t;
  48
  49 static const op_tbl_t op_table [] = {
  50         { "-lt", LT },
  51         { "<"  , LT },
  52         { "-gt", GT },
  53         { ">"  , GT },
  54         { "-eq", EQ },
  55         { "==" , EQ },
  56         { "-ne", NE },
  57         { "!=" , NE },
  58         { "<>" , NE },
  59         { "-ge", GE },
  60         { ">=" , GE },
  61         { "-le", LE },
  62         { "<=" , LE },
  63 };
  64
  65 static long evalexp(char *s, int w)
  66 {
  67         long l = 0;
  68         long *p;
  69
  70         /* if the parameter starts with a * then assume is a pointer to the value we want */
  71         if (s[0] == '*') {
  72                 p = (long *)simple_strtoul(&s[1], NULL, 16);
  73                 switch (w) {
  74                 case 1: return((long)(*(unsigned char *)p));
  75                 case 2: return((long)(*(unsigned short *)p));
  76                 case 4: return(*p);
  77                 }
  78         } else {
  79                 l = simple_strtoul(s, NULL, 16);
  80         }
  81
  82         return (l & ((1 << (w * 8)) - 1));
  83 }
  84
  85 static char * evalstr(char *s)
  86 {
  87         /* if the parameter starts with a * then assume a string pointer else its a literal */
  88         if (s[0] == '*') {
  89                 return (char *)simple_strtoul(&s[1], NULL, 16);
  90         } else {
  91                 return s;
  92         }
  93 }
  94
  95 static int stringcomp(char *s, char *t, int op)
  96 {
  97         int p;
  98         char *l, *r;
  99
 100         l = evalstr(s);
 101         r = evalstr(t);
 102
 103         p = strcmp(l, r);
 104         switch (op) {
 105         case EQ: return (p == 0);
 106         case NE: return (p != 0);
 107         case LT: return (p < 0);
 108         case GT: return (p > 0);
 109         case LE: return (p <= 0);
 110         case GE: return (p >= 0);
 111         }
 112         return (0);
 113 }
 114
 115 static int arithcomp (char *s, char *t, int op, int w)
 116 {
 117         long l, r;
 118
 119         l = evalexp (s, w);
 120         r = evalexp (t, w);
 121
 122         switch (op) {
 123         case EQ: return (l == r);
 124         case NE: return (l != r);
 125         case LT: return (l < r);
 126         case GT: return (l > r);
 127         case LE: return (l <= r);
 128         case GE: return (l >= r);
 129         }
 130         return (0);
 131 }
 132
 133 static int binary_test(char *op, char *arg1, char *arg2, int w)
 134 {
 135         int len, i;
 136         const op_tbl_t *optp;
 137
 138         len = strlen(op);
 139
 140         for (optp = (op_tbl_t *)&op_table, i = 0;
 141              i < ARRAY_SIZE(op_table);
 142              optp++, i++) {
 143
 144                 if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
 145                         if (w == 0) {
 146                                 return (stringcomp(arg1, arg2, optp->opcode));
 147                         } else {
 148                                 return (arithcomp (arg1, arg2, optp->opcode, w));
 149                         }
 150                 }
 151         }
 152
 153         printf("Unknown operator '%s'\n", op);
 154         return 0;       /* op code not found */
 155 }
 156
 157 /* command line interface to the shell test */
 158 static int do_itest(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 159 {
 160         int     value, w;
 161
 162         /* Validate arguments */
 163         if ((argc != 4))
 164                 return CMD_RET_USAGE;
 165
 166         /* Check for a data width specification.
 167          * Defaults to long (4) if no specification.
 168          * Uses -2 as 'width' for .s (string) so as not to upset existing code
 169          */
 170         switch (w = cmd_get_data_size(argv[0], 4)) {
 171         case 1:
 172         case 2:
 173         case 4:
 174                 value = binary_test (argv[2], argv[1], argv[3], w);
 175                 break;
 176         case -2:
 177                 value = binary_test (argv[2], argv[1], argv[3], 0);
 178                 break;
 179         case -1:
 180         default:
 181                 puts("Invalid data width specifier\n");
 182                 value = 0;
 183                 break;
 184         }
 185
 186         return !value;
 187 }
 188
 189 U_BOOT_CMD(
 190         itest, 4, 0, do_itest,
 191         "return true/false on integer compare",
 192         "[.b, .w, .l, .s] [*]value1 <op> [*]value2"
 193 );