1 /*
2  * Copyright (c) 2004 Esben Norby <norby@openbsd.org>
3  * Copyright (c) 2003, 2004 Henning Brauer <henning@openbsd.org>
4  *
5  * Permission to use, copy, modify, and distribute this software for any
6  * purpose with or without fee is hereby granted, provided that the above
7  * copyright notice and this permission notice appear in all copies.
8  *
9  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16  */
17 
18 #include "compat.h"
19 
20 #include <stdint.h>
21 #include <stdio.h>
22 #include <string.h>
23 
24 #include "ctl_parser.h"
25 #include "kamid.h"
26 
27 enum token_type {
28 	NOTOKEN,
29 	ENDTOKEN,
30 	KEYWORD,
31 };
32 
33 struct token {
34 	enum token_type		 type;
35 	const char		*keyword;
36 	int			 value;
37 	const struct token	*next;
38 };
39 
40 static const struct token t_main[];
41 static const struct token t_log[];
42 
43 static const struct token t_main[] = {
44 	{KEYWORD,	"reload",	RELOAD,		NULL},
45 	{KEYWORD,	"log",		NONE,		t_log},
46 	{KEYWORD,	"debug",	DEBUG,		NULL},
47 	{ENDTOKEN,	"",		NONE,		NULL},
48 };
49 
50 static const struct token t_log[] = {
51 	{KEYWORD,	"verbose",	LOG_VERBOSE,	NULL},
52 	{KEYWORD,	"brief",	LOG_BRIEF,	NULL},
53 	{ENDTOKEN,	"",		NONE,		NULL},
54 };
55 
56 static const struct token *match_token(const char *, const struct token *,
57     struct parse_result *);
58 static void show_valid_args(const struct token *);
59 
60 struct parse_result *
61 parse(int argc, char **argv)
62 {
63 	static struct parse_result	 res;
64 	const struct token		*table = t_main;
65 	const struct token		*match;
66 
67 	memset(&res, 0, sizeof(res));
68 
69 	while (argc >= 0) {
70 		if ((match = match_token(argv[0], table, &res)) == NULL) {
71 			fprintf(stderr, "valid commands/args:\n");
72 			show_valid_args(table);
73 			return NULL;
74 		}
75 
76 		argc--;
77 		argv++;
78 
79 		if (match->type == NOTOKEN || match->next == NULL)
80 			break;
81 
82 		table = match->next;
83 	}
84 
85 	if (argc > 0) {
86 		fprintf(stderr, "superfluous argument: %s\n", argv[0]);
87 		return NULL;
88 	}
89 
90 	return &res;
91 }
92 
93 static const struct token *
94 match_token(const char *word, const struct token *table,
95     struct parse_result *res)
96 {
97 	size_t			 i, match;
98 	const struct token	*t = NULL;
99 
100 	match = 0;
101 
102 	for (i = 0; table[i].type != ENDTOKEN; i++) {
103 		switch (table[i].type) {
104 		case NOTOKEN:
105 			if (word == NULL || strlen(word) == 0) {
106 				match++;
107 				t = &table[i];
108 			}
109 			break;
110 		case KEYWORD:
111 			if (word != NULL && strncmp(word, table[i].keyword,
112 			    strlen(word)) == 0) {
113 				match++;
114 				t = &table[i];
115 				if (t->value)
116 					res->action = t->value;
117 			}
118 			break;
119 		case ENDTOKEN:
120 			break;
121 		}
122 	}
123 
124 	if (match != 1) {
125 		if (word == NULL)
126 			fprintf(stderr, "missing argument:\n");
127 		else if (match > 1)
128 			fprintf(stderr, "ambiuous argument: %s\n", word);
129 		else if (match < 1)
130 			fprintf(stderr, "unknown argument: %s\n", word);
131 		return NULL;
132 	}
133 
134 	return t;
135 }
136 
137 static void
138 show_valid_args(const struct token *table)
139 {
140 	int i;
141 
142 	for (i = 0; table[i].type != ENDTOKEN; i++) {
143 		switch (table[i].type) {
144 		case NOTOKEN:
145 			fprintf(stderr, "  <cr>\n");
146 			break;
147 		case KEYWORD:
148 			fprintf(stderr, "  %s\n", table[i].keyword);
149 			break;
150 		case ENDTOKEN:
151 			break;
152 		}
153 	}
154 }