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 <env.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 
evalexp(char * s,int w)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 #ifdef CONFIG_PHYS_64BIT
77 		case 8:
78 			l = (long)(*(unsigned long *)buf);
79 			break;
80 #endif
81 		}
82 		unmap_physmem(buf, w);
83 		return l;
84 	} else {
85 		l = simple_strtoul(s, NULL, 16);
86 	}
87 
88 	/* avoid overflow on mask calculus */
89 	return (w >= sizeof(long)) ? l : (l & ((1UL << (w * 8)) - 1));
90 }
91 
evalstr(char * s)92 static char * evalstr(char *s)
93 {
94 	/* if the parameter starts with a * then assume a string pointer else its a literal */
95 	if (s[0] == '*') {
96 		return (char *)simple_strtoul(&s[1], NULL, 16);
97 	} else if (s[0] == '$') {
98 		int i = 2;
99 
100 		if (s[1] != '{')
101 			return NULL;
102 
103 		while (s[i] != '}') {
104 			if (s[i] == 0)
105 				return NULL;
106 			i++;
107 		}
108 		s[i] = 0;
109 		return  env_get((const char *)&s[2]);
110 	} else {
111 		return s;
112 	}
113 }
114 
stringcomp(char * s,char * t,int op)115 static int stringcomp(char *s, char *t, int op)
116 {
117 	int p;
118 	char *l, *r;
119 
120 	l = evalstr(s);
121 	r = evalstr(t);
122 
123 	p = strcmp(l, r);
124 	switch (op) {
125 	case EQ: return (p == 0);
126 	case NE: return (p != 0);
127 	case LT: return (p < 0);
128 	case GT: return (p > 0);
129 	case LE: return (p <= 0);
130 	case GE: return (p >= 0);
131 	}
132 	return (0);
133 }
134 
arithcomp(char * s,char * t,int op,int w)135 static int arithcomp (char *s, char *t, int op, int w)
136 {
137 	long l, r;
138 
139 	l = evalexp (s, w);
140 	r = evalexp (t, w);
141 
142 	switch (op) {
143 	case EQ: return (l == r);
144 	case NE: return (l != r);
145 	case LT: return (l < r);
146 	case GT: return (l > r);
147 	case LE: return (l <= r);
148 	case GE: return (l >= r);
149 	}
150 	return (0);
151 }
152 
binary_test(char * op,char * arg1,char * arg2,int w)153 static int binary_test(char *op, char *arg1, char *arg2, int w)
154 {
155 	int len, i;
156 	const op_tbl_t *optp;
157 
158 	len = strlen(op);
159 
160 	for (optp = (op_tbl_t *)&op_table, i = 0;
161 	     i < ARRAY_SIZE(op_table);
162 	     optp++, i++) {
163 
164 		if ((strncmp (op, optp->op, len) == 0) && (len == strlen (optp->op))) {
165 			if (w == 0) {
166 				return (stringcomp(arg1, arg2, optp->opcode));
167 			} else {
168 				return (arithcomp (arg1, arg2, optp->opcode, w));
169 			}
170 		}
171 	}
172 
173 	printf("Unknown operator '%s'\n", op);
174 	return 0;	/* op code not found */
175 }
176 
177 /* command line interface to the shell test */
do_itest(struct cmd_tbl * cmdtp,int flag,int argc,char * const argv[])178 static int do_itest(struct cmd_tbl *cmdtp, int flag, int argc,
179 		    char *const argv[])
180 {
181 	int	value, w;
182 
183 	/* Validate arguments */
184 	if ((argc != 4))
185 		return CMD_RET_USAGE;
186 
187 	/* Check for a data width specification.
188 	 * Defaults to long (4) if no specification.
189 	 * Uses -2 as 'width' for .s (string) so as not to upset existing code
190 	 */
191 	switch (w = cmd_get_data_size(argv[0], 4)) {
192 	case 1:
193 	case 2:
194 	case 4:
195 #ifdef CONFIG_PHYS_64BIT
196 	case 8:
197 #endif
198 		value = binary_test (argv[2], argv[1], argv[3], w);
199 		break;
200 	case CMD_DATA_SIZE_STR:
201 		value = binary_test (argv[2], argv[1], argv[3], 0);
202 		break;
203 	case CMD_DATA_SIZE_ERR:
204 	default:
205 		puts("Invalid data width specifier\n");
206 		value = 0;
207 		break;
208 	}
209 
210 	return !value;
211 }
212 
213 U_BOOT_CMD(
214 	itest, 4, 0, do_itest,
215 	"return true/false on integer compare",
216 #ifdef CONFIG_PHYS_64BIT
217 	"[.b, .w, .l, .q, .s] [*]value1 <op> [*]value2"
218 #else
219 	"[.b, .w, .l, .s] [*]value1 <op> [*]value2"
220 #endif
221 );
222