aboutsummaryrefslogtreecommitdiff
path: root/common/env_common.c
blob: f387f9ab91f6897acb24b1e55c204279f6e26657 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
/*
 * (C) Copyright 2000-2010
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * (C) Copyright 2001 Sysgo Real-Time Solutions, GmbH <www.elinos.com>
 * Andreas Heppel <aheppel@sysgo.de>
 *
 * SPDX-License-Identifier:	GPL-2.0+ 
 */

#include <common.h>
#include <command.h>
#include <environment.h>
#include <linux/stddef.h>
#include <search.h>
#include <errno.h>
#include <malloc.h>

DECLARE_GLOBAL_DATA_PTR;

/************************************************************************
 * Default settings to be used when no valid environment is found
 */
#include <env_default.h>

struct hsearch_data env_htab = {
	.change_ok = env_flags_validate,
};

static uchar __env_get_char_spec(int index)
{
	return *((uchar *)(gd->env_addr + index));
}
uchar env_get_char_spec(int)
	__attribute__((weak, alias("__env_get_char_spec")));

static uchar env_get_char_init(int index)
{
	/* if crc was bad, use the default environment */
	if (gd->env_valid)
		return env_get_char_spec(index);
	else
		return default_environment[index];
}

uchar env_get_char_memory(int index)
{
	return *env_get_addr(index);
}

uchar env_get_char(int index)
{
	/* if relocated to RAM */
	if (gd->flags & GD_FLG_RELOC)
		return env_get_char_memory(index);
	else
		return env_get_char_init(index);
}

const uchar *env_get_addr(int index)
{
	if (gd->env_valid)
		return (uchar *)(gd->env_addr + index);
	else
		return &default_environment[index];
}

/*
 * Read an environment variable as a boolean
 * Return -1 if variable does not exist (default to true)
 */
int getenv_yesno(const char *var)
{
	char *s = getenv(var);

	if (s == NULL)
		return -1;
	return (*s == '1' || *s == 'y' || *s == 'Y' || *s == 't' || *s == 'T') ?
		1 : 0;
}

/*
 * Look up the variable from the default environment
 */
char *getenv_default(const char *name)
{
	char *ret_val;
	unsigned long really_valid = gd->env_valid;
	unsigned long real_gd_flags = gd->flags;

	/* Pretend that the image is bad. */
	gd->flags &= ~GD_FLG_ENV_READY;
	gd->env_valid = 0;
	ret_val = getenv(name);
	gd->env_valid = really_valid;
	gd->flags = real_gd_flags;
	return ret_val;
}

void set_default_env(const char *s)
{
	int flags = 0;

	if (sizeof(default_environment) > ENV_SIZE) {
		puts("*** Error - default environment is too large\n\n");
		return;
	}

	if (s) {
		if (*s == '!') {
			printf("*** Warning - %s, "
				"using default environment\n\n",
				s + 1);
		} else {
			flags = H_INTERACTIVE;
			puts(s);
		}
	} else {
		puts("Using default environment\n\n");
	}

	if (himport_r(&env_htab, (char *)default_environment,
			sizeof(default_environment), '\0', flags,
			0, NULL) == 0)
		error("Environment import failed: errno = %d\n", errno);

	gd->flags |= GD_FLG_ENV_READY;
}


/* [re]set individual variables to their value in the default environment */
int set_default_vars(int nvars, char * const vars[])
{
	/*
	 * Special use-case: import from default environment
	 * (and use \0 as a separator)
	 */
	return himport_r(&env_htab, (const char *)default_environment,
				sizeof(default_environment), '\0',
				H_NOCLEAR | H_INTERACTIVE, nvars, vars);
}

#ifndef CONFIG_SPL_BUILD
/*
 * Check if CRC is valid and (if yes) import the environment.
 * Note that "buf" may or may not be aligned.
 */
int env_import(const char *buf, int check)
{
	env_t *ep = (env_t *)buf;

	if (check) {
		uint32_t crc;

		memcpy(&crc, &ep->crc, sizeof(crc));

		if (crc32(0, ep->data, ENV_SIZE) != crc) {
			set_default_env("!bad CRC");
			return 0;
		}
	}

	if (himport_r(&env_htab, (char *)ep->data, ENV_SIZE, '\0', 0,
			0, NULL)) {
		gd->flags |= GD_FLG_ENV_READY;
		return 1;
	}

	error("Cannot import environment: errno = %d\n", errno);

	set_default_env("!import failed");

	return 0;
}
#endif

void env_relocate(void)
{
#if defined(CONFIG_NEEDS_MANUAL_RELOC)
	env_reloc();
	env_htab.change_ok += gd->reloc_off;
#endif
	if (gd->env_valid == 0) {
#if defined(CONFIG_ENV_IS_NOWHERE) || defined(CONFIG_SPL_BUILD)
		/* Environment not changable */
		set_default_env(NULL);
#else
		bootstage_error(BOOTSTAGE_ID_NET_CHECKSUM);
		set_default_env("!bad CRC");
#endif
	} else {
		env_relocate_spec();
	}
}

#if defined(CONFIG_AUTO_COMPLETE) && !defined(CONFIG_SPL_BUILD)
int env_complete(char *var, int maxv, char *cmdv[], int bufsz, char *buf)
{
	ENTRY *match;
	int found, idx;

	idx = 0;
	found = 0;
	cmdv[0] = NULL;

	while ((idx = hmatch_r(var, idx, &match, &env_htab))) {
		int vallen = strlen(match->key) + 1;

		if (found >= maxv - 2 || bufsz < vallen)
			break;

		cmdv[found++] = buf;
		memcpy(buf, match->key, vallen);
		buf += vallen;
		bufsz -= vallen;
	}

	qsort(cmdv, found, sizeof(cmdv[0]), strcmp_compar);

	if (idx)
		cmdv[found++] = "...";

	cmdv[found] = NULL;
	return found;
}
#endif