1 /* vi: set sw=4 ts=4: */
2 /*
3  * Utility routines.
4  *
5  * Copyright (C) 1999-2004 by Erik Andersen <andersen@codepoet.org>
6  *
7  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
8  */
9 #include "libbb.h"
10 #if ENABLE_FEATURE_SYSLOG
11 # include <syslog.h>
12 #endif
13 
14 #if ENABLE_FEATURE_SYSLOG
15 static smallint syslog_level = LOG_ERR;
16 #endif
17 smallint logmode = LOGMODE_STDIO;
18 const char *msg_eol = "\n";
19 
bb_verror_msg(const char * s,va_list p,const char * strerr)20 void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
21 {
22 	char *msg, *msg1;
23 	char stack_msg[80];
24 	int applet_len, strerr_len, msgeol_len, used;
25 
26 	if (!logmode)
27 		return;
28 
29 	if (!s) /* nomsg[_and_die] uses NULL fmt */
30 		s = ""; /* some libc don't like printf(NULL) */
31 
32 	applet_len = strlen(applet_name) + 2; /* "applet: " */
33 	strerr_len = strerr ? strlen(strerr) : 0;
34 	msgeol_len = strlen(msg_eol);
35 
36 	/* This costs ~90 bytes of code, but avoids costly
37 	 * malloc()[in vasprintf]+realloc()+memmove()+free() in 99% of cases.
38 	 * ~40% speedup.
39 	 */
40 	if ((int)sizeof(stack_msg) - applet_len > 0) {
41 		va_list p2;
42 
43 		/* It is not portable to use va_list twice, need to va_copy it */
44 		va_copy(p2, p);
45 		used = vsnprintf(stack_msg + applet_len, (int)sizeof(stack_msg) - applet_len, s, p2);
46 		va_end(p2);
47 		msg = stack_msg;
48 		used += applet_len;
49 		if (used < (int)sizeof(stack_msg) - 3 - msgeol_len - strerr_len)
50 			goto add_pfx_and_sfx;
51 	}
52 
53 	used = vasprintf(&msg, s, p);
54 	if (used < 0)
55 		return;
56 
57 	/* This is ugly and costs +60 bytes compared to multiple
58 	 * fprintf's, but is guaranteed to do a single write.
59 	 * This is needed for e.g. httpd logging, when multiple
60 	 * children can produce log messages simultaneously. */
61 
62 	/* can't use xrealloc: it calls error_msg on failure,
63 	 * that may result in a recursion */
64 	/* +3 is for ": " before strerr and for terminating NUL */
65 	msg1 = realloc(msg, applet_len + used + strerr_len + msgeol_len + 3);
66 	if (!msg1) {
67 		msg[used++] = '\n'; /* overwrites NUL */
68 		applet_len = 0;
69 	} else {
70 		msg = msg1;
71 		/* TODO: maybe use writev instead of memmoving? Need full_writev? */
72 		memmove(msg + applet_len, msg, used);
73 		used += applet_len;
74  add_pfx_and_sfx:
75 		strcpy(msg, applet_name);
76 		msg[applet_len - 2] = ':';
77 		msg[applet_len - 1] = ' ';
78 		if (strerr) {
79 			if (s[0]) { /* not perror_nomsg? */
80 				msg[used++] = ':';
81 				msg[used++] = ' ';
82 			}
83 			strcpy(&msg[used], strerr);
84 			used += strerr_len;
85 		}
86 		strcpy(&msg[used], msg_eol);
87 		used += msgeol_len;
88 	}
89 
90 	if (logmode & LOGMODE_STDIO) {
91 		fflush_all();
92 		full_write(STDERR_FILENO, msg, used);
93 	}
94 #if ENABLE_FEATURE_SYSLOG
95 	if (logmode & LOGMODE_SYSLOG) {
96 		syslog(syslog_level, "%s", msg + applet_len);
97 	}
98 #endif
99 	if (msg != stack_msg)
100 		free(msg);
101 }
102 
103 #ifdef VERSION_WITH_WRITEV
104 /* Code size is approximately the same, but currently it's the only user
105  * of writev in entire bbox. __libc_writev in uclibc is ~50 bytes. */
bb_verror_msg(const char * s,va_list p,const char * strerr)106 void FAST_FUNC bb_verror_msg(const char *s, va_list p, const char* strerr)
107 {
108 	int strerr_len, msgeol_len;
109 	struct iovec iov[3];
110 
111 #define used   (iov[2].iov_len)
112 #define msgv   (iov[2].iov_base)
113 #define msgc   ((char*)(iov[2].iov_base))
114 #define msgptr (&(iov[2].iov_base))
115 
116 	if (!logmode)
117 		return;
118 
119 	if (!s) /* nomsg[_and_die] uses NULL fmt */
120 		s = ""; /* some libc don't like printf(NULL) */
121 
122 	/* Prevent "derefing type-punned ptr will break aliasing rules" */
123 	used = vasprintf((char**)(void*)msgptr, s, p);
124 	if (used < 0)
125 		return;
126 
127 	/* This is ugly and costs +60 bytes compared to multiple
128 	 * fprintf's, but is guaranteed to do a single write.
129 	 * This is needed for e.g. httpd logging, when multiple
130 	 * children can produce log messages simultaneously. */
131 
132 	strerr_len = strerr ? strlen(strerr) : 0;
133 	msgeol_len = strlen(msg_eol);
134 	/* +3 is for ": " before strerr and for terminating NUL */
135 	msgv = xrealloc(msgv, used + strerr_len + msgeol_len + 3);
136 	if (strerr) {
137 		msgc[used++] = ':';
138 		msgc[used++] = ' ';
139 		strcpy(msgc + used, strerr);
140 		used += strerr_len;
141 	}
142 	strcpy(msgc + used, msg_eol);
143 	used += msgeol_len;
144 
145 	if (logmode & LOGMODE_STDIO) {
146 		iov[0].iov_base = (char*)applet_name;
147 		iov[0].iov_len = strlen(applet_name);
148 		iov[1].iov_base = (char*)": ";
149 		iov[1].iov_len = 2;
150 		/*iov[2].iov_base = msgc;*/
151 		/*iov[2].iov_len = used;*/
152 		fflush_all();
153 		writev(STDERR_FILENO, iov, 3);
154 	}
155 # if ENABLE_FEATURE_SYSLOG
156 	if (logmode & LOGMODE_SYSLOG) {
157 		syslog(syslog_level, "%s", msgc);
158 	}
159 # endif
160 	free(msgc);
161 }
162 #endif
163 
164 
bb_error_msg_and_die(const char * s,...)165 void FAST_FUNC bb_error_msg_and_die(const char *s, ...)
166 {
167 	va_list p;
168 
169 	va_start(p, s);
170 	bb_verror_msg(s, p, NULL);
171 	va_end(p);
172 	xfunc_die();
173 }
174 
bb_error_msg(const char * s,...)175 void FAST_FUNC bb_error_msg(const char *s, ...)
176 {
177 	va_list p;
178 
179 	va_start(p, s);
180 	bb_verror_msg(s, p, NULL);
181 	va_end(p);
182 }
183 
184 #if ENABLE_FEATURE_SYSLOG_INFO
bb_vinfo_msg(const char * s,va_list p)185 void FAST_FUNC bb_vinfo_msg(const char *s, va_list p)
186 {
187 	syslog_level = LOG_INFO;
188 	bb_verror_msg(s, p, NULL);
189 	syslog_level = LOG_ERR;
190 }
191 
bb_info_msg(const char * s,...)192 void FAST_FUNC bb_info_msg(const char *s, ...)
193 {
194 	va_list p;
195 
196 	va_start(p, s);
197 	bb_vinfo_msg(s, p);
198 	va_end(p);
199 }
200 
bb_simple_info_msg(const char * s)201 void FAST_FUNC bb_simple_info_msg(const char *s)
202 {
203 	bb_info_msg("%s", s);
204 }
205 #endif
206 
bb_simple_error_msg(const char * s)207 void FAST_FUNC bb_simple_error_msg(const char *s)
208 {
209 	bb_error_msg("%s", s);
210 }
211 
bb_simple_error_msg_and_die(const char * s)212 void FAST_FUNC bb_simple_error_msg_and_die(const char *s)
213 {
214 	bb_error_msg_and_die("%s", s);
215 }
216