discover/grub2: Add nops for unnecessary builtins
[petitboot] / discover / grub2 / builtins.c
1
2 #include <stdio.h>
3 #include <string.h>
4
5 #include <log/log.h>
6 #include <types/types.h>
7 #include <talloc/talloc.h>
8 #include <array-size/array-size.h>
9
10 #include "grub2.h"
11
12
13 static int builtin_set(struct grub2_script *script,
14                 void *data __attribute__((unused)),
15                 int argc, char *argv[])
16 {
17         char *name, *value, *p;
18         int i;
19
20         if (argc < 2)
21                 return -1;
22
23         p = strchr(argv[1], '=');
24         if (!p)
25                 return -1;
26
27         name = talloc_strndup(script, argv[1], p - argv[1]);
28         value = talloc_strdup(script, p+1);
29
30         for (i = 2; i < argc; i++)
31                 value = talloc_asprintf_append(value, " %s", argv[i]);
32
33         script_env_set(script, name, value);
34
35         return 0;
36 }
37
38 static int builtin_linux(struct grub2_script *script,
39                 void *data __attribute__((unused)),
40                 int argc, char *argv[])
41 {
42         struct discover_boot_option *opt = script->opt;
43         const char *root;
44         int i;
45
46         if (!opt) {
47                 pb_log("grub2 syntax error: 'linux' statement outside "
48                                 "a menuentry.\n");
49                 return -1;
50         }
51
52         if (argc < 2) {
53                 pb_log("grub2 syntax error: no filename provided to "
54                                 "linux statement\n");
55                 return -1;
56         }
57
58         root = script_env_get(script, "root");
59
60         opt->boot_image = create_grub2_resource(opt, script->ctx->device,
61                                                 root, argv[1]);
62         opt->option->boot_args = NULL;
63
64         if (argc > 2)
65                 opt->option->boot_args = talloc_strdup(opt, argv[2]);
66
67         for (i = 3; i < argc; i++)
68                 opt->option->boot_args = talloc_asprintf_append(
69                                                 opt->option->boot_args,
70                                                 " %s", argv[i]);
71         return 0;
72 }
73
74 static int builtin_initrd(struct grub2_script *script,
75                 void *data __attribute__((unused)),
76                 int argc, char *argv[])
77 {
78         struct discover_boot_option *opt = script->opt;
79         const char *root;
80
81         if (!opt) {
82                 pb_log("grub2 syntax error: 'initrd' statement outside "
83                                 "a menuentry.\n");
84                 return -1;
85         }
86
87         if (argc < 2) {
88                 pb_log("grub2 syntax error: no filename provided to "
89                                 "initrd statement\n");
90                 return -1;
91         }
92
93         root = script_env_get(script, "root");
94         opt->initrd = create_grub2_resource(opt, script->ctx->device,
95                                                 root, argv[1]);
96
97         return 0;
98 }
99
100 static int builtin_search(struct grub2_script *script,
101                 void *data __attribute__((unused)),
102                 int argc, char *argv[])
103 {
104         const char *env_var, *spec;
105         int i;
106
107         env_var = NULL;
108
109         for (i = 1; i < argc - 1; i++) {
110                 if (!strncmp(argv[i], "--set=", strlen("--set="))) {
111                         env_var = argv[i] + strlen("--set=");
112                         break;
113                 }
114         }
115
116         if (!env_var)
117                 return 0;
118
119         spec = argv[argc - 1];
120
121         script_env_set(script, env_var, spec);
122
123         return 0;
124 }
125
126 static int builtin_nop(struct grub2_script *script __attribute__((unused)),
127                 void *data __attribute__((unused)),
128                 int argc __attribute__((unused)),
129                 char *argv[] __attribute__((unused)))
130 {
131         return 0;
132 }
133
134 static struct {
135         const char *name;
136         grub2_function fn;
137 } builtins[] = {
138         {
139                 .name = "set",
140                 .fn = builtin_set,
141         },
142         {
143                 .name = "linux",
144                 .fn = builtin_linux,
145         },
146         {
147                 .name = "initrd",
148                 .fn = builtin_initrd,
149         },
150         {
151                 .name = "search",
152                 .fn = builtin_search,
153         }
154 };
155
156 static const char *nops[] = {
157         "echo", "export", "insmod", "loadfont", "terminfo",
158 };
159
160 void register_builtins(struct grub2_script *script)
161 {
162         unsigned int i;
163
164         for (i = 0; i < ARRAY_SIZE(builtins); i++)
165                 script_register_function(script, builtins[i].name,
166                                 builtins[i].fn, NULL);
167
168         for (i = 0; i < ARRAY_SIZE(nops); i++)
169                 script_register_function(script, nops[i], builtin_nop, NULL);
170 }