1 /* $NetBSD: rec_streamlf.c,v 1.1.1.1 2009/06/23 10:08:47 tron Exp $ */
2
3 /*++
4 /* NAME
5 /* rec_streamlf 3
6 /* SUMMARY
7 /* record interface to stream-lf files
8 /* SYNOPSIS
9 /* #include <rec_streamlf.h>
10 /*
11 /* int rec_streamlf_get(stream, buf, maxlen)
12 /* VSTREAM *stream;
13 /* VSTRING *buf;
14 /* int maxlen;
15 /*
16 /* int rec_streamlf_put(stream, type, data, len)
17 /* VSTREAM *stream;
18 /* int type;
19 /* const char *data;
20 /* int len;
21 /* AUXILIARY FUNCTIONS
22 /* int REC_STREAMLF_PUT_BUF(stream, type, buf)
23 /* VSTREAM *stream;
24 /* int type;
25 /* VSTRING *buf;
26 /* DESCRIPTION
27 /* This module implements record I/O on top of stream-lf files.
28 /*
29 /* rec_streamlf_get() reads one record from the specified stream.
30 /* The result is null-terminated and may contain embedded null
31 /* characters.
32 /* The \fImaxlen\fR argument specifies an upper bound to the amount
33 /* of data read. The result is REC_TYPE_NORM when the record was
34 /* terminated by newline, REC_TYPE_CONT when no terminating newline
35 /* was found (the record was larger than \fImaxlen\fR characters or
36 /* EOF was reached), and REC_TYPE_EOF when no data could be read or
37 /* when an I/O error was detected.
38 /*
39 /* rec_streamlf_put() writes one record to the named stream.
40 /* When the record type is REC_TYPE_NORM, a newline character is
41 /* appended to the output. The result is the record type, or
42 /* REC_TYPE_EOF in case of problems.
43 /*
44 /* REC_STREAMLF_PUT_BUF() is a wrapper for rec_streamlf_put() that
45 /* makes it more convenient to output VSTRING buffers.
46 /* REC_STREAMLF_PUT_BUF() is an unsafe macro that evaluates some
47 /* arguments more than once.
48 /* SEE ALSO
49 /* record(3) typed records
50 /* LICENSE
51 /* .ad
52 /* .fi
53 /* The Secure Mailer license must be distributed with this software.
54 /* AUTHOR(S)
55 /* Wietse Venema
56 /* IBM T.J. Watson Research
57 /* P.O. Box 704
58 /* Yorktown Heights, NY 10598, USA
59 /*--*/
60
61 /* System library. */
62
63 #include <sys_defs.h>
64
65 /* Utility library. */
66
67 #include <vstring.h>
68 #include <vstream.h>
69
70 /* Global library. */
71
72 #include <record.h>
73 #include <rec_type.h>
74 #include <rec_streamlf.h>
75
76 /* rec_streamlf_get - read record from stream-lf file */
77
rec_streamlf_get(VSTREAM * stream,VSTRING * buf,int maxlen)78 int rec_streamlf_get(VSTREAM *stream, VSTRING *buf, int maxlen)
79 {
80 int n = maxlen;
81 int ch;
82
83 /*
84 * If this one character ar a time code proves to be a performance
85 * bottleneck, switch to block search (memchr()) and to block move
86 * (memcpy()) operations.
87 */
88 VSTRING_RESET(buf);
89 while (n-- > 0) {
90 if ((ch = VSTREAM_GETC(stream)) == VSTREAM_EOF)
91 return (VSTRING_LEN(buf) > 0 ? REC_TYPE_CONT : REC_TYPE_EOF);
92 if (ch == '\n') {
93 VSTRING_TERMINATE(buf);
94 return (REC_TYPE_NORM);
95 }
96 VSTRING_ADDCH(buf, ch);
97 }
98 VSTRING_TERMINATE(buf);
99 return (REC_TYPE_CONT);
100 }
101
102 /* rec_streamlf_put - write record to stream-lf file */
103
rec_streamlf_put(VSTREAM * stream,int type,const char * data,int len)104 int rec_streamlf_put(VSTREAM *stream, int type, const char *data, int len)
105 {
106 if (len > 0)
107 (void) vstream_fwrite(stream, data, len);
108 if (type == REC_TYPE_NORM)
109 (void) VSTREAM_PUTC('\n', stream);
110 return (vstream_ferror(stream) ? REC_TYPE_EOF : type);
111 }
112