xref: /freebsd/lib/libc/gen/fmtmsg.c (revision d4eeb02986980bf33dd56c41ceb9fc5f180c0d47)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 2002 Mike Barcroft <mike@FreeBSD.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 #include <fmtmsg.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 
37 /* Default value for MSGVERB. */
38 #define	DFLT_MSGVERB	"label:severity:text:action:tag"
39 
40 /* Maximum valid size for a MSGVERB. */
41 #define	MAX_MSGVERB	sizeof(DFLT_MSGVERB)
42 
43 static char	*printfmt(char *, long, const char *, int, const char *,
44 		    const char *, const char *);
45 static char	*nextcomp(const char *);
46 static const char
47 		*sevinfo(int);
48 static int	 validmsgverb(const char *);
49 
50 int
51 fmtmsg(long class, const char *label, int sev, const char *text,
52     const char *action, const char *tag)
53 {
54 	FILE *fp;
55 	char *env, *msgverb, *output;
56 
57 	if (class & MM_PRINT) {
58 		if ((env = getenv("MSGVERB")) != NULL && *env != '\0' &&
59 		    strlen(env) <= strlen(DFLT_MSGVERB)) {
60 			if ((msgverb = strdup(env)) == NULL)
61 				return (MM_NOTOK);
62 			else if (validmsgverb(msgverb) == 0) {
63 				free(msgverb);
64 				goto def;
65 			}
66 		} else {
67 def:
68 			if ((msgverb = strdup(DFLT_MSGVERB)) == NULL)
69 				return (MM_NOTOK);
70 		}
71 		output = printfmt(msgverb, class, label, sev, text, action,
72 		    tag);
73 		if (output == NULL) {
74 			free(msgverb);
75 			return (MM_NOTOK);
76 		}
77 		if (*output != '\0')
78 			fprintf(stderr, "%s", output);
79 		free(msgverb);
80 		free(output);
81 	}
82 	if (class & MM_CONSOLE) {
83 		output = printfmt(DFLT_MSGVERB, class, label, sev, text,
84 		    action, tag);
85 		if (output == NULL)
86 			return (MM_NOCON);
87 		if (*output != '\0') {
88 			if ((fp = fopen("/dev/console", "ae")) == NULL) {
89 				free(output);
90 				return (MM_NOCON);
91 			}
92 			fprintf(fp, "%s", output);
93 			fclose(fp);
94 		}
95 		free(output);
96 	}
97 	return (MM_OK);
98 }
99 
100 #define INSERT_COLON							\
101 	if (*output != '\0')						\
102 		strlcat(output, ": ", size)
103 #define INSERT_NEWLINE							\
104 	if (*output != '\0')						\
105 		strlcat(output, "\n", size)
106 #define INSERT_SPACE							\
107 	if (*output != '\0')						\
108 		strlcat(output, " ", size)
109 
110 /*
111  * Returns NULL on memory allocation failure, otherwise returns a pointer to
112  * a newly malloc()'d output buffer.
113  */
114 static char *
115 printfmt(char *msgverb, long class, const char *label, int sev,
116     const char *text, const char *act, const char *tag)
117 {
118 	size_t size;
119 	char *comp, *output;
120 	const char *sevname;
121 
122 	size = 32;
123 	if (label != MM_NULLLBL)
124 		size += strlen(label);
125 	if ((sevname = sevinfo(sev)) != NULL)
126 		size += strlen(sevname);
127 	if (text != MM_NULLTXT)
128 		size += strlen(text);
129 	if (act != MM_NULLACT)
130 		size += strlen(act);
131 	if (tag != MM_NULLTAG)
132 		size += strlen(tag);
133 
134 	if ((output = malloc(size)) == NULL)
135 		return (NULL);
136 	*output = '\0';
137 	while ((comp = nextcomp(msgverb)) != NULL) {
138 		if (strcmp(comp, "label") == 0 && label != MM_NULLLBL) {
139 			INSERT_COLON;
140 			strlcat(output, label, size);
141 		} else if (strcmp(comp, "severity") == 0 && sevname != NULL) {
142 			INSERT_COLON;
143 			strlcat(output, sevinfo(sev), size);
144 		} else if (strcmp(comp, "text") == 0 && text != MM_NULLTXT) {
145 			INSERT_COLON;
146 			strlcat(output, text, size);
147 		} else if (strcmp(comp, "action") == 0 && act != MM_NULLACT) {
148 			INSERT_NEWLINE;
149 			strlcat(output, "TO FIX: ", size);
150 			strlcat(output, act, size);
151 		} else if (strcmp(comp, "tag") == 0 && tag != MM_NULLTAG) {
152 			INSERT_SPACE;
153 			strlcat(output, tag, size);
154 		}
155 	}
156 	INSERT_NEWLINE;
157 	return (output);
158 }
159 
160 /*
161  * Returns a component of a colon delimited string.  NULL is returned to
162  * indicate that there are no remaining components.  This function must be
163  * called until it returns NULL in order for the local state to be cleared.
164  */
165 static char *
166 nextcomp(const char *msgverb)
167 {
168 	static char lmsgverb[MAX_MSGVERB], *state;
169 	char *retval;
170 
171 	if (*lmsgverb == '\0') {
172 		strlcpy(lmsgverb, msgverb, sizeof(lmsgverb));
173 		retval = strtok_r(lmsgverb, ":", &state);
174 	} else {
175 		retval = strtok_r(NULL, ":", &state);
176 	}
177 	if (retval == NULL)
178 		*lmsgverb = '\0';
179 	return (retval);
180 }
181 
182 static const char *
183 sevinfo(int sev)
184 {
185 
186 	switch (sev) {
187 	case MM_HALT:
188 		return ("HALT");
189 	case MM_ERROR:
190 		return ("ERROR");
191 	case MM_WARNING:
192 		return ("WARNING");
193 	case MM_INFO:
194 		return ("INFO");
195 	default:
196 		return (NULL);
197 	}
198 }
199 
200 /*
201  * Returns 1 if the msgverb list is valid, otherwise 0.
202  */
203 static int
204 validmsgverb(const char *msgverb)
205 {
206 	const char *validlist = "label\0severity\0text\0action\0tag\0";
207 	char *msgcomp;
208 	size_t len1, len2;
209 	const char *p;
210 	int equality;
211 
212 	equality = 0;
213 	while ((msgcomp = nextcomp(msgverb)) != NULL) {
214 		equality--;
215 		len1 = strlen(msgcomp);
216 		for (p = validlist; (len2 = strlen(p)) != 0; p += len2 + 1) {
217 			if (len1 == len2 && memcmp(msgcomp, p, len1) == 0)
218 				equality++;
219 		}
220 	}
221 	return (!equality);
222 }
223