xref: /freebsd/lib/libc/gen/fmtmsg.c (revision 7899f917b1c0ea178f1d2be0cfb452086d079d23)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause
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 <fmtmsg.h>
30 #include <stdio.h>
31 #include <stdlib.h>
32 #include <string.h>
33 
34 /* Default value for MSGVERB. */
35 #define	DFLT_MSGVERB	"label:severity:text:action:tag"
36 
37 /* Maximum valid size for a MSGVERB. */
38 #define	MAX_MSGVERB	sizeof(DFLT_MSGVERB)
39 
40 static char	*printfmt(char *, long, const char *, int, const char *,
41 		    const char *, const char *);
42 static char	*nextcomp(const char *);
43 static const char
44 		*sevinfo(int);
45 static int	 validmsgverb(const char *);
46 
47 int
48 fmtmsg(long class, const char *label, int sev, const char *text,
49     const char *action, const char *tag)
50 {
51 	FILE *fp;
52 	char *env, *msgverb, *output;
53 
54 	if (class & MM_PRINT) {
55 		if ((env = getenv("MSGVERB")) != NULL && *env != '\0' &&
56 		    strlen(env) <= strlen(DFLT_MSGVERB)) {
57 			if ((msgverb = strdup(env)) == NULL)
58 				return (MM_NOTOK);
59 			else if (validmsgverb(msgverb) == 0) {
60 				free(msgverb);
61 				goto def;
62 			}
63 		} else {
64 def:
65 			if ((msgverb = strdup(DFLT_MSGVERB)) == NULL)
66 				return (MM_NOTOK);
67 		}
68 		output = printfmt(msgverb, class, label, sev, text, action,
69 		    tag);
70 		if (output == NULL) {
71 			free(msgverb);
72 			return (MM_NOTOK);
73 		}
74 		if (*output != '\0')
75 			fprintf(stderr, "%s", output);
76 		free(msgverb);
77 		free(output);
78 	}
79 	if (class & MM_CONSOLE) {
80 		output = printfmt(DFLT_MSGVERB, class, label, sev, text,
81 		    action, tag);
82 		if (output == NULL)
83 			return (MM_NOCON);
84 		if (*output != '\0') {
85 			if ((fp = fopen("/dev/console", "ae")) == NULL) {
86 				free(output);
87 				return (MM_NOCON);
88 			}
89 			fprintf(fp, "%s", output);
90 			fclose(fp);
91 		}
92 		free(output);
93 	}
94 	return (MM_OK);
95 }
96 
97 #define INSERT_COLON							\
98 	if (*output != '\0')						\
99 		strlcat(output, ": ", size)
100 #define INSERT_NEWLINE							\
101 	if (*output != '\0')						\
102 		strlcat(output, "\n", size)
103 #define INSERT_SPACE							\
104 	if (*output != '\0')						\
105 		strlcat(output, " ", size)
106 
107 /*
108  * Returns NULL on memory allocation failure, otherwise returns a pointer to
109  * a newly malloc()'d output buffer.
110  */
111 static char *
112 printfmt(char *msgverb, long class, const char *label, int sev,
113     const char *text, const char *act, const char *tag)
114 {
115 	size_t size;
116 	char *comp, *output;
117 	const char *sevname;
118 
119 	size = 32;
120 	if (label != MM_NULLLBL)
121 		size += strlen(label);
122 	if ((sevname = sevinfo(sev)) != NULL)
123 		size += strlen(sevname);
124 	if (text != MM_NULLTXT)
125 		size += strlen(text);
126 	if (act != MM_NULLACT)
127 		size += strlen(act);
128 	if (tag != MM_NULLTAG)
129 		size += strlen(tag);
130 
131 	if ((output = malloc(size)) == NULL)
132 		return (NULL);
133 	*output = '\0';
134 	while ((comp = nextcomp(msgverb)) != NULL) {
135 		if (strcmp(comp, "label") == 0 && label != MM_NULLLBL) {
136 			INSERT_COLON;
137 			strlcat(output, label, size);
138 		} else if (strcmp(comp, "severity") == 0 && sevname != NULL) {
139 			INSERT_COLON;
140 			strlcat(output, sevinfo(sev), size);
141 		} else if (strcmp(comp, "text") == 0 && text != MM_NULLTXT) {
142 			INSERT_COLON;
143 			strlcat(output, text, size);
144 		} else if (strcmp(comp, "action") == 0 && act != MM_NULLACT) {
145 			INSERT_NEWLINE;
146 			strlcat(output, "TO FIX: ", size);
147 			strlcat(output, act, size);
148 		} else if (strcmp(comp, "tag") == 0 && tag != MM_NULLTAG) {
149 			INSERT_SPACE;
150 			strlcat(output, tag, size);
151 		}
152 	}
153 	INSERT_NEWLINE;
154 	return (output);
155 }
156 
157 /*
158  * Returns a component of a colon delimited string.  NULL is returned to
159  * indicate that there are no remaining components.  This function must be
160  * called until it returns NULL in order for the local state to be cleared.
161  */
162 static char *
163 nextcomp(const char *msgverb)
164 {
165 	static char lmsgverb[MAX_MSGVERB], *state;
166 	char *retval;
167 
168 	if (*lmsgverb == '\0') {
169 		strlcpy(lmsgverb, msgverb, sizeof(lmsgverb));
170 		retval = strtok_r(lmsgverb, ":", &state);
171 	} else {
172 		retval = strtok_r(NULL, ":", &state);
173 	}
174 	if (retval == NULL)
175 		*lmsgverb = '\0';
176 	return (retval);
177 }
178 
179 static const char *
180 sevinfo(int sev)
181 {
182 
183 	switch (sev) {
184 	case MM_HALT:
185 		return ("HALT");
186 	case MM_ERROR:
187 		return ("ERROR");
188 	case MM_WARNING:
189 		return ("WARNING");
190 	case MM_INFO:
191 		return ("INFO");
192 	default:
193 		return (NULL);
194 	}
195 }
196 
197 /*
198  * Returns 1 if the msgverb list is valid, otherwise 0.
199  */
200 static int
201 validmsgverb(const char *msgverb)
202 {
203 	const char *validlist = "label\0severity\0text\0action\0tag\0";
204 	char *msgcomp;
205 	size_t len1, len2;
206 	const char *p;
207 	int equality;
208 
209 	equality = 0;
210 	while ((msgcomp = nextcomp(msgverb)) != NULL) {
211 		equality--;
212 		len1 = strlen(msgcomp);
213 		for (p = validlist; (len2 = strlen(p)) != 0; p += len2 + 1) {
214 			if (len1 == len2 && memcmp(msgcomp, p, len1) == 0)
215 				equality++;
216 		}
217 	}
218 	return (!equality);
219 }
220