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 tarball for details.
8 */
9
10#include <syslog.h>
11#include "libbb.h"
12
13smallint logmode = LOGMODE_STDIO;
14const char *msg_eol = "\n";
15
16void bb_verror_msg(const char *s, va_list p, const char* strerr)
17{
18	char *msg;
19	int applet_len, strerr_len, msgeol_len, used;
20
21	if (!logmode)
22		return;
23
24	if (!s) /* nomsg[_and_die] uses NULL fmt */
25		s = ""; /* some libc don't like printf(NULL) */
26
27	used = vasprintf(&msg, s, p);
28	if (used < 0)
29		return;
30
31	/* This is ugly and costs +60 bytes compared to multiple
32	 * fprintf's, but is guaranteed to do a single write.
33	 * This is needed for e.g. httpd logging, when multiple
34	 * children can produce log messages simultaneously. */
35
36	applet_len = strlen(applet_name) + 2; /* "applet: " */
37	strerr_len = strerr ? strlen(strerr) : 0;
38	msgeol_len = strlen(msg_eol);
39	/* +3 is for ": " before strerr and for terminating NUL */
40	msg = xrealloc(msg, applet_len + used + strerr_len + msgeol_len + 3);
41	/* TODO: maybe use writev instead of memmoving? Need full_writev? */
42	memmove(msg + applet_len, msg, used);
43	used += applet_len;
44	strcpy(msg, applet_name);
45	msg[applet_len - 2] = ':';
46	msg[applet_len - 1] = ' ';
47	if (strerr) {
48		msg[used++] = ':';
49		msg[used++] = ' ';
50		strcpy(&msg[used], strerr);
51		used += strerr_len;
52	}
53	strcpy(&msg[used], msg_eol);
54
55	if (logmode & LOGMODE_STDIO) {
56		fflush(stdout);
57		full_write(2, msg, used + msgeol_len);
58	}
59	if (logmode & LOGMODE_SYSLOG) {
60		syslog(LOG_ERR, "%s", msg + applet_len);
61	}
62	free(msg);
63}
64
65
66#ifdef VERSION_WITH_WRITEV
67
68/* Code size is approximately the same, but currently it's the only user
69 * of writev in entire bbox. __libc_writev in uclibc is ~50 bytes. */
70
71void bb_verror_msg(const char *s, va_list p, const char* strerr)
72{
73	int strerr_len, msgeol_len;
74	struct iovec iov[3];
75
76#define used   (iov[2].iov_len)
77#define msgv   (iov[2].iov_base)
78#define msgc   ((char*)(iov[2].iov_base))
79#define msgptr (&(iov[2].iov_base))
80
81	if (!logmode)
82		return;
83
84	if (!s) /* nomsg[_and_die] uses NULL fmt */
85		s = ""; /* some libc don't like printf(NULL) */
86
87	/* Prevent "derefing type-punned ptr will break aliasing rules" */
88	used = vasprintf((char**)(void*)msgptr, s, p);
89	if (used < 0)
90		return;
91
92	/* This is ugly and costs +60 bytes compared to multiple
93	 * fprintf's, but is guaranteed to do a single write.
94	 * This is needed for e.g. httpd logging, when multiple
95	 * children can produce log messages simultaneously. */
96
97	strerr_len = strerr ? strlen(strerr) : 0;
98	msgeol_len = strlen(msg_eol);
99	/* +3 is for ": " before strerr and for terminating NUL */
100	msgv = xrealloc(msgv, used + strerr_len + msgeol_len + 3);
101	if (strerr) {
102		msgc[used++] = ':';
103		msgc[used++] = ' ';
104		strcpy(msgc + used, strerr);
105		used += strerr_len;
106	}
107	strcpy(msgc + used, msg_eol);
108	used += msgeol_len;
109
110	if (logmode & LOGMODE_STDIO) {
111		iov[0].iov_base = (char*)applet_name;
112		iov[0].iov_len = strlen(applet_name);
113		iov[1].iov_base = (char*)": ";
114		iov[1].iov_len = 2;
115		/*iov[2].iov_base = msgc;*/
116		/*iov[2].iov_len = used;*/
117		fflush(stdout);
118		writev(2, iov, 3);
119	}
120	if (logmode & LOGMODE_SYSLOG) {
121		syslog(LOG_ERR, "%s", msgc);
122	}
123	free(msgc);
124}
125#endif
126