cmd/itest.c

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