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 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 #define op_tbl_size (sizeof(op_table)/sizeof(op_table[0]))
  66
  67 static long evalexp(char *s, int w)
  68 {
  69         long l = 0;
  70         long *p;
  71
  72         /* if the parameter starts with a * then assume is a pointer to the value we want */
  73         if (s[0] == '*') {
  74                 p = (long *)simple_strtoul(&s[1], NULL, 16);
  75                 switch (w) {
  76                 case 1: return((long)(*(unsigned char *)p));
  77                 case 2: return((long)(*(unsigned short *)p));
  78                 case 4: return(*p);
  79                 }
  80         } else {
  81                 l = simple_strtoul(s, NULL, 16);
  82         }
  83
  84         return (l & ((1 << (w * 8)) - 1));
  85 }
  86
  87 static char * evalstr(char *s)
  88 {
  89         /* if the parameter starts with a * then assume a string pointer else its a literal */
  90         if (s[0] == '*') {
  91                 return (char *)simple_strtoul(&s[1], NULL, 16);
  92         } else {
  93                 return s;
  94         }
  95 }
  96
  97 static int stringcomp(char *s, char *t, int op)
  98 {
  99         int n, p;
 100         char *l, *r;
 101
 102         l = evalstr(s);
 103         r = evalstr(t);
 104
 105         /* we'll do a compare based on the length of the shortest string */
 106         n = min(strlen(l), strlen(r));
 107
 108         p = strncmp(l, r, n);
 109         switch (op) {
 110         case EQ: return (p == 0);
 111         case NE: return (p != 0);
 112         case LT: return (p < 0);
 113         case GT: return (p > 0);
 114         case LE: return (p <= 0);
 115         case GE: return (p >= 0);
 116         }
 117         return (0);
 118 }
 119
 120 static int arithcomp (char *s, char *t, int op, int w)
 121 {
 122         long l, r;
 123
 124         l = evalexp (s, w);
 125         r = evalexp (t, w);
 126
 127         switch (op) {
 128         case EQ: return (l == r);
 129         case NE: return (l != r);
 130         case LT: return (l < r);
 131         case GT: return (l > r);
 132         case LE: return (l <= r);
 133         case GE: return (l >= r);
 134         }
 135         return (0);
 136 }
 137
 138 int binary_test (char *op, char *arg1, char *arg2, int w)
 139 {
 140         int len, i;
 141         op_tbl_t *optp;
 142
 143         len = strlen(op);
 144
 145         for (optp = (op_tbl_t *)&op_table, i = 0;
 146              i < op_tbl_size;
 147              optp++, i++) {
 148
 149                 if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
 150                         if (w == 0) {
 151                                 return (stringcomp(arg1, arg2, optp->opcode));
 152                         } else {
 153                                 return (arithcomp (arg1, arg2, optp->opcode, w));
 154                         }
 155                 }
 156         }
 157
 158         printf("Unknown operator '%s'\n", op);
 159         return 0;       /* op code not found */
 160 }
 161
 162 /* command line interface to the shell test */
 163 int do_itest ( cmd_tbl_t *cmdtp, int flag, int argc, char *argv[] )
 164 {
 165         int     value, w;
 166
 167         /* Validate arguments */
 168         if ((argc != 4)){
 169                 cmd_usage(cmdtp);
 170                 return 1;
 171         }
 172
 173         /* Check for a data width specification.
 174          * Defaults to long (4) if no specification.
 175          * Uses -2 as 'width' for .s (string) so as not to upset existing code
 176          */
 177         switch (w = cmd_get_data_size(argv[0], 4)) {
 178         case 1:
 179         case 2:
 180         case 4:
 181                 value = binary_test (argv[2], argv[1], argv[3], w);
 182                 break;
 183         case -2:
 184                 value = binary_test (argv[2], argv[1], argv[3], 0);
 185                 break;
 186         case -1:
 187         default:
 188                 puts("Invalid data width specifier\n");
 189                 value = 0;
 190                 break;
 191         }
 192
 193         return !value;
 194 }
 195
 196 U_BOOT_CMD(
 197         itest, 4, 0, do_itest,
 198         "return true/false on integer compare",
 199         "[.b, .w, .l, .s] [*]value1 <op> [*]value2"
 200 );