cmd/itest.c

   1 /*
   2  * (C) Copyright 2003
   3  * Tait Electronics Limited, Christchurch, New Zealand
   4  *
   5  * SPDX-License-Identifier:     GPL-2.0+
   6  */
   7
   8 /*
   9  * This file provides a shell like 'test' function to return
  10  * true/false from an integer or string compare of two memory
  11  * locations or a location and a scalar/literal.
  12  * A few parts were lifted from bash 'test' command
  13  */
  14
  15 #include <common.h>
  16 #include <config.h>
  17 #include <command.h>
  18 #include <mapmem.h>
  19
  20 #include <asm/io.h>
  21
  22 #define EQ      0
  23 #define NE      1
  24 #define LT      2
  25 #define GT      3
  26 #define LE      4
  27 #define GE      5
  28
  29 struct op_tbl_s {
  30         char    *op;            /* operator string */
  31         int     opcode;         /* internal representation of opcode */
  32 };
  33
  34 typedef struct op_tbl_s op_tbl_t;
  35
  36 static const op_tbl_t op_table [] = {
  37         { "-lt", LT },
  38         { "<"  , LT },
  39         { "-gt", GT },
  40         { ">"  , GT },
  41         { "-eq", EQ },
  42         { "==" , EQ },
  43         { "-ne", NE },
  44         { "!=" , NE },
  45         { "<>" , NE },
  46         { "-ge", GE },
  47         { ">=" , GE },
  48         { "-le", LE },
  49         { "<=" , LE },
  50 };
  51
  52 static long evalexp(char *s, int w)
  53 {
  54         long l = 0;
  55         unsigned long addr;
  56         void *buf;
  57
  58         /* if the parameter starts with a * then assume is a pointer to the value we want */
  59         if (s[0] == '*') {
  60                 addr = simple_strtoul(&s[1], NULL, 16);
  61                 buf = map_physmem(addr, w, MAP_WRBACK);
  62                 if (!buf && addr) {
  63                         puts("Failed to map physical memory\n");
  64                         return 0;
  65                 }
  66                 switch (w) {
  67                 case 1:
  68                         l = (long)(*(u8 *)buf);
  69                         break;
  70                 case 2:
  71                         l = (long)(*(u16 *)buf);
  72                         break;
  73                 case 4:
  74                         l = (long)(*(u32 *)buf);
  75                         break;
  76                 }
  77                 unmap_physmem(buf, w);
  78                 return l;
  79         } else {
  80                 l = simple_strtoul(s, NULL, 16);
  81         }
  82
  83         /* avoid overflow on mask calculus */
  84         return (w >= sizeof(long)) ? l : (l & ((1UL << (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 if (s[0] == '$') {
  93                 int i = 2;
  94
  95                 if (s[1] != '{')
  96                         return NULL;
  97
  98                 while (s[i] != '}') {
  99                         if (s[i] == 0)
 100                                 return NULL;
 101                         i++;
 102                 }
 103                 s[i] = 0;
 104                 return  env_get((const char *)&s[2]);
 105         } else {
 106                 return s;
 107         }
 108 }
 109
 110 static int stringcomp(char *s, char *t, int op)
 111 {
 112         int p;
 113         char *l, *r;
 114
 115         l = evalstr(s);
 116         r = evalstr(t);
 117
 118         p = strcmp(l, r);
 119         switch (op) {
 120         case EQ: return (p == 0);
 121         case NE: return (p != 0);
 122         case LT: return (p < 0);
 123         case GT: return (p > 0);
 124         case LE: return (p <= 0);
 125         case GE: return (p >= 0);
 126         }
 127         return (0);
 128 }
 129
 130 static int arithcomp (char *s, char *t, int op, int w)
 131 {
 132         long l, r;
 133
 134         l = evalexp (s, w);
 135         r = evalexp (t, w);
 136
 137         switch (op) {
 138         case EQ: return (l == r);
 139         case NE: return (l != r);
 140         case LT: return (l < r);
 141         case GT: return (l > r);
 142         case LE: return (l <= r);
 143         case GE: return (l >= r);
 144         }
 145         return (0);
 146 }
 147
 148 static int binary_test(char *op, char *arg1, char *arg2, int w)
 149 {
 150         int len, i;
 151         const op_tbl_t *optp;
 152
 153         len = strlen(op);
 154
 155         for (optp = (op_tbl_t *)&op_table, i = 0;
 156              i < ARRAY_SIZE(op_table);
 157              optp++, i++) {
 158
 159                 if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
 160                         if (w == 0) {
 161                                 return (stringcomp(arg1, arg2, optp->opcode));
 162                         } else {
 163                                 return (arithcomp (arg1, arg2, optp->opcode, w));
 164                         }
 165                 }
 166         }
 167
 168         printf("Unknown operator '%s'\n", op);
 169         return 0;       /* op code not found */
 170 }
 171
 172 /* command line interface to the shell test */
 173 static int do_itest(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
 174 {
 175         int     value, w;
 176
 177         /* Validate arguments */
 178         if ((argc != 4))
 179                 return CMD_RET_USAGE;
 180
 181         /* Check for a data width specification.
 182          * Defaults to long (4) if no specification.
 183          * Uses -2 as 'width' for .s (string) so as not to upset existing code
 184          */
 185         switch (w = cmd_get_data_size(argv[0], 4)) {
 186         case 1:
 187         case 2:
 188         case 4:
 189                 value = binary_test (argv[2], argv[1], argv[3], w);
 190                 break;
 191         case -2:
 192                 value = binary_test (argv[2], argv[1], argv[3], 0);
 193                 break;
 194         case -1:
 195         default:
 196                 puts("Invalid data width specifier\n");
 197                 value = 0;
 198                 break;
 199         }
 200
 201         return !value;
 202 }
 203
 204 U_BOOT_CMD(
 205         itest, 4, 0, do_itest,
 206         "return true/false on integer compare",
 207         "[.b, .w, .l, .s] [*]value1 <op> [*]value2"
 208 );