xref: /netbsd-src/external/ibm-public/postfix/dist/src/cleanup/cleanup_out.c (revision 413d532bcc3f62d122e56d92e13ac64825a40baf)
1 /*	$NetBSD: cleanup_out.c,v 1.1.1.1 2009/06/23 10:08:43 tron Exp $	*/
2 
3 /*++
4 /* NAME
5 /*	cleanup_out 3
6 /* SUMMARY
7 /*	record output support
8 /* SYNOPSIS
9 /*	#include "cleanup.h"
10 /*
11 /*	int	CLEANUP_OUT_OK(state)
12 /*	CLEANUP_STATE *state;
13 /*
14 /*	void	cleanup_out(state, type, data, len)
15 /*	CLEANUP_STATE *state;
16 /*	int	type;
17 /*	const char *data;
18 /*	ssize_t	len;
19 /*
20 /*	void	cleanup_out_string(state, type, str)
21 /*	CLEANUP_STATE *state;
22 /*	int	type;
23 /*	const char *str;
24 /*
25 /*	void	CLEANUP_OUT_BUF(state, type, buf)
26 /*	CLEANUP_STATE *state;
27 /*	int	type;
28 /*	VSTRING	*buf;
29 /*
30 /*	void	cleanup_out_format(state, type, format, ...)
31 /*	CLEANUP_STATE *state;
32 /*	int	type;
33 /*	const char *format;
34 /*
35 /*	void	cleanup_out_header(state, buf)
36 /*	CLEANUP_STATE *state;
37 /*	VSTRING	*buf;
38 /* DESCRIPTION
39 /*	This module writes records to the output stream.
40 /*
41 /*	CLEANUP_OUT_OK() is a macro that evaluates to non-zero
42 /*	as long as it makes sense to produce output. All output
43 /*	routines below check for this condition.
44 /*
45 /*	cleanup_out() is the main record output routine. It writes
46 /*	one record of the specified type, with the specified data
47 /*	and length to the output stream.
48 /*
49 /*	cleanup_out_string() outputs one string as a record.
50 /*
51 /*	CLEANUP_OUT_BUF() is an unsafe macro that outputs
52 /*	one string buffer as a record.
53 /*
54 /*	cleanup_out_format() formats its arguments and writes
55 /*	the result as a record.
56 /*
57 /*	cleanup_out_header() outputs a multi-line header as records
58 /*	of the specified type. The input is expected to be newline
59 /*	separated (not newline terminated), and is modified.
60 /* LICENSE
61 /* .ad
62 /* .fi
63 /*	The Secure Mailer license must be distributed with this software.
64 /* AUTHOR(S)
65 /*	Wietse Venema
66 /*	IBM T.J. Watson Research
67 /*	P.O. Box 704
68 /*	Yorktown Heights, NY 10598, USA
69 /*--*/
70 
71 /* System library. */
72 
73 #include <sys_defs.h>
74 #include <errno.h>
75 #include <stdlib.h>			/* 44BSD stdarg.h uses abort() */
76 #include <stdarg.h>
77 #include <string.h>
78 
79 /* Utility library. */
80 
81 #include <msg.h>
82 #include <vstring.h>
83 #include <vstream.h>
84 #include <split_at.h>
85 
86 /* Global library. */
87 
88 #include <record.h>
89 #include <rec_type.h>
90 #include <cleanup_user.h>
91 #include <mail_params.h>
92 #include <lex_822.h>
93 
94 /* Application-specific. */
95 
96 #include "cleanup.h"
97 
98 /* cleanup_out - output one single record */
99 
100 void    cleanup_out(CLEANUP_STATE *state, int type, const char *string, ssize_t len)
101 {
102     int     err = 0;
103 
104     /*
105      * Long message header lines have to be read and written as multiple
106      * records. Other header/body content, and envelope data, is copied one
107      * record at a time. Be sure to not skip a zero-length request.
108      *
109      * XXX We don't know if we're writing a message header or not, but that is
110      * not a problem. A REC_TYPE_NORM or REC_TYPE_CONT record can always be
111      * chopped up into an equivalent set of REC_TYPE_CONT plus REC_TYPE_NORM
112      * records.
113      */
114     if (CLEANUP_OUT_OK(state) == 0)
115 	return;
116 
117 #define TEXT_RECORD(t)	((t) == REC_TYPE_NORM || (t) == REC_TYPE_CONT)
118 
119     if (var_line_limit <= 0)
120 	msg_panic("cleanup_out: bad line length limit: %d", var_line_limit);
121     do {
122 	if (len > var_line_limit && TEXT_RECORD(type)) {
123 	    err = rec_put(state->dst, REC_TYPE_CONT, string, var_line_limit);
124 	    string += var_line_limit;
125 	    len -= var_line_limit;
126 	} else {
127 	    err = rec_put(state->dst, type, string, len);
128 	    break;
129 	}
130     } while (len > 0 && err >= 0);
131 
132     if (err < 0) {
133 	if (errno == EFBIG) {
134 	    msg_warn("%s: queue file size limit exceeded",
135 		     state->queue_id);
136 	    state->errs |= CLEANUP_STAT_SIZE;
137 	} else {
138 	    msg_warn("%s: write queue file: %m", state->queue_id);
139 	    state->errs |= CLEANUP_STAT_WRITE;
140 	}
141     }
142 }
143 
144 /* cleanup_out_string - output string to one single record */
145 
146 void    cleanup_out_string(CLEANUP_STATE *state, int type, const char *string)
147 {
148     cleanup_out(state, type, string, strlen(string));
149 }
150 
151 /* cleanup_out_format - output one formatted record */
152 
153 void    cleanup_out_format(CLEANUP_STATE *state, int type, const char *fmt,...)
154 {
155     static VSTRING *vp;
156     va_list ap;
157 
158     if (vp == 0)
159 	vp = vstring_alloc(100);
160     va_start(ap, fmt);
161     vstring_vsprintf(vp, fmt, ap);
162     va_end(ap);
163     CLEANUP_OUT_BUF(state, type, vp);
164 }
165 
166 /* cleanup_out_header - output one multi-line header as a bunch of records */
167 
168 void    cleanup_out_header(CLEANUP_STATE *state, VSTRING *header_buf)
169 {
170     char   *start = vstring_str(header_buf);
171     char   *line;
172     char   *next_line;
173     ssize_t line_len;
174 
175     /*
176      * Prepend a tab to continued header lines that went through the address
177      * rewriting machinery. See cleanup_fold_header(state) below for the form
178      * of such header lines. NB: This code destroys the header. We could try
179      * to avoid clobbering it, but we're not going to use the data any
180      * further.
181      *
182      * XXX We prefer to truncate a header at the last line boundary before the
183      * header size limit. If this would undershoot the limit by more than
184      * 10%, we truncate between line boundaries to avoid losing too much
185      * text. This "unkind cut" may result in syntax errors and may trigger
186      * warnings from down-stream MTAs.
187      *
188      * If Milter is enabled, pad a short header record with a dummy record so
189      * that a header record can safely be overwritten by a pointer record.
190      * This simplifies header modification enormously.
191      */
192     for (line = start; line; line = next_line) {
193 	next_line = split_at(line, '\n');
194 	line_len = next_line ? next_line - 1 - line : strlen(line);
195 	if (line + line_len > start + var_header_limit) {
196 	    if (line - start > 0.9 * var_header_limit)	/* nice cut */
197 		break;
198 	    start[var_header_limit] = 0;	/* unkind cut */
199 	    next_line = 0;
200 	}
201 	if (line == start) {
202 	    cleanup_out_string(state, REC_TYPE_NORM, line);
203 	    if ((state->milters || cleanup_milters)
204 		&& line_len < REC_TYPE_PTR_PAYL_SIZE)
205 		rec_pad(state->dst, REC_TYPE_DTXT,
206 			REC_TYPE_PTR_PAYL_SIZE - line_len);
207 	} else if (IS_SPACE_TAB(*line)) {
208 	    cleanup_out_string(state, REC_TYPE_NORM, line);
209 	} else {
210 	    cleanup_out_format(state, REC_TYPE_NORM, "\t%s", line);
211 	}
212     }
213 }
214