xref: /freebsd/lib/libc/gen/fmtmsg.c (revision 22cf89c938886d14f5796fc49f9f020c23ea8eaf)
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 <sys/cdefs.h>
30 #include <fmtmsg.h>
31 #include <stdio.h>
32 #include <stdlib.h>
33 #include <string.h>
34 
35 /* Default value for MSGVERB. */
36 #define	DFLT_MSGVERB	"label:severity:text:action:tag"
37 
38 /* Maximum valid size for a MSGVERB. */
39 #define	MAX_MSGVERB	sizeof(DFLT_MSGVERB)
40 
41 static char	*printfmt(char *, long, const char *, int, const char *,
42 		    const char *, const char *);
43 static char	*nextcomp(const char *);
44 static const char
45 		*sevinfo(int);
46 static int	 validmsgverb(const char *);
47 
48 int
49 fmtmsg(long class, const char *label, int sev, const char *text,
50     const char *action, const char *tag)
51 {
52 	FILE *fp;
53 	char *env, *msgverb, *output;
54 
55 	if (class & MM_PRINT) {
56 		if ((env = getenv("MSGVERB")) != NULL && *env != '\0' &&
57 		    strlen(env) <= strlen(DFLT_MSGVERB)) {
58 			if ((msgverb = strdup(env)) == NULL)
59 				return (MM_NOTOK);
60 			else if (validmsgverb(msgverb) == 0) {
61 				free(msgverb);
62 				goto def;
63 			}
64 		} else {
65 def:
66 			if ((msgverb = strdup(DFLT_MSGVERB)) == NULL)
67 				return (MM_NOTOK);
68 		}
69 		output = printfmt(msgverb, class, label, sev, text, action,
70 		    tag);
71 		if (output == NULL) {
72 			free(msgverb);
73 			return (MM_NOTOK);
74 		}
75 		if (*output != '\0')
76 			fprintf(stderr, "%s", output);
77 		free(msgverb);
78 		free(output);
79 	}
80 	if (class & MM_CONSOLE) {
81 		output = printfmt(DFLT_MSGVERB, class, label, sev, text,
82 		    action, tag);
83 		if (output == NULL)
84 			return (MM_NOCON);
85 		if (*output != '\0') {
86 			if ((fp = fopen("/dev/console", "ae")) == NULL) {
87 				free(output);
88 				return (MM_NOCON);
89 			}
90 			fprintf(fp, "%s", output);
91 			fclose(fp);
92 		}
93 		free(output);
94 	}
95 	return (MM_OK);
96 }
97 
98 #define INSERT_COLON							\
99 	if (*output != '\0')						\
100 		strlcat(output, ": ", size)
101 #define INSERT_NEWLINE							\
102 	if (*output != '\0')						\
103 		strlcat(output, "\n", size)
104 #define INSERT_SPACE							\
105 	if (*output != '\0')						\
106 		strlcat(output, " ", size)
107 
108 /*
109  * Returns NULL on memory allocation failure, otherwise returns a pointer to
110  * a newly malloc()'d output buffer.
111  */
112 static char *
113 printfmt(char *msgverb, long class, const char *label, int sev,
114     const char *text, const char *act, const char *tag)
115 {
116 	size_t size;
117 	char *comp, *output;
118 	const char *sevname;
119 
120 	size = 32;
121 	if (label != MM_NULLLBL)
122 		size += strlen(label);
123 	if ((sevname = sevinfo(sev)) != NULL)
124 		size += strlen(sevname);
125 	if (text != MM_NULLTXT)
126 		size += strlen(text);
127 	if (act != MM_NULLACT)
128 		size += strlen(act);
129 	if (tag != MM_NULLTAG)
130 		size += strlen(tag);
131 
132 	if ((output = malloc(size)) == NULL)
133 		return (NULL);
134 	*output = '\0';
135 	while ((comp = nextcomp(msgverb)) != NULL) {
136 		if (strcmp(comp, "label") == 0 && label != MM_NULLLBL) {
137 			INSERT_COLON;
138 			strlcat(output, label, size);
139 		} else if (strcmp(comp, "severity") == 0 && sevname != NULL) {
140 			INSERT_COLON;
141 			strlcat(output, sevinfo(sev), size);
142 		} else if (strcmp(comp, "text") == 0 && text != MM_NULLTXT) {
143 			INSERT_COLON;
144 			strlcat(output, text, size);
145 		} else if (strcmp(comp, "action") == 0 && act != MM_NULLACT) {
146 			INSERT_NEWLINE;
147 			strlcat(output, "TO FIX: ", size);
148 			strlcat(output, act, size);
149 		} else if (strcmp(comp, "tag") == 0 && tag != MM_NULLTAG) {
150 			INSERT_SPACE;
151 			strlcat(output, tag, size);
152 		}
153 	}
154 	INSERT_NEWLINE;
155 	return (output);
156 }
157 
158 /*
159  * Returns a component of a colon delimited string.  NULL is returned to
160  * indicate that there are no remaining components.  This function must be
161  * called until it returns NULL in order for the local state to be cleared.
162  */
163 static char *
164 nextcomp(const char *msgverb)
165 {
166 	static char lmsgverb[MAX_MSGVERB], *state;
167 	char *retval;
168 
169 	if (*lmsgverb == '\0') {
170 		strlcpy(lmsgverb, msgverb, sizeof(lmsgverb));
171 		retval = strtok_r(lmsgverb, ":", &state);
172 	} else {
173 		retval = strtok_r(NULL, ":", &state);
174 	}
175 	if (retval == NULL)
176 		*lmsgverb = '\0';
177 	return (retval);
178 }
179 
180 static const char *
181 sevinfo(int sev)
182 {
183 
184 	switch (sev) {
185 	case MM_HALT:
186 		return ("HALT");
187 	case MM_ERROR:
188 		return ("ERROR");
189 	case MM_WARNING:
190 		return ("WARNING");
191 	case MM_INFO:
192 		return ("INFO");
193 	default:
194 		return (NULL);
195 	}
196 }
197 
198 /*
199  * Returns 1 if the msgverb list is valid, otherwise 0.
200  */
201 static int
202 validmsgverb(const char *msgverb)
203 {
204 	const char *validlist = "label\0severity\0text\0action\0tag\0";
205 	char *msgcomp;
206 	size_t len1, len2;
207 	const char *p;
208 	int equality;
209 
210 	equality = 0;
211 	while ((msgcomp = nextcomp(msgverb)) != NULL) {
212 		equality--;
213 		len1 = strlen(msgcomp);
214 		for (p = validlist; (len2 = strlen(p)) != 0; p += len2 + 1) {
215 			if (len1 == len2 && memcmp(msgcomp, p, len1) == 0)
216 				equality++;
217 		}
218 	}
219 	return (!equality);
220 }
221