1 /***********************************************************************
2 * *
3 * This software is part of the ast package *
4 * Copyright (c) 1985-2010 AT&T Intellectual Property *
5 * and is licensed under the *
6 * Common Public License, Version 1.0 *
7 * by AT&T Intellectual Property *
8 * *
9 * A copy of the License is available at *
10 * http://www.opensource.org/licenses/cpl1.0.txt *
11 * (with md5 checksum 059e8cd6165cb4c31e351f2b69388fd9) *
12 * *
13 * Information and Software Systems Research *
14 * AT&T Research *
15 * Florham Park NJ *
16 * *
17 * Glenn Fowler <gsf@research.att.com> *
18 * David Korn <dgk@research.att.com> *
19 * Phong Vo <kpv@research.att.com> *
20 * *
21 ***********************************************************************/
22 #include "sfdchdr.h"
23
24 /*
25 * a discipline that prepends a prefix string to each output line
26 *
27 * Glenn Fowler
28 * AT&T Research
29 *
30 * @(#)$Id: sfdcprefix (AT&T Research) 1998-06-25 $
31 */
32
33 typedef struct
34 {
35 Sfdisc_t disc; /* sfio discipline */
36 size_t length; /* prefix length */
37 size_t empty; /* empty line prefix length */
38 int skip; /* this line already prefixed */
39 char prefix[1]; /* prefix string */
40 } Prefix_t;
41
42 /*
43 * prefix write
44 */
45
46 #if __STD_C
pfxwrite(Sfio_t * f,const Void_t * buf,register size_t n,Sfdisc_t * dp)47 static ssize_t pfxwrite(Sfio_t* f, const Void_t* buf, register size_t n, Sfdisc_t* dp)
48 #else
49 static ssize_t pfxwrite(f, buf, n, dp)
50 Sfio_t* f;
51 Void_t* buf;
52 register size_t n;
53 Sfdisc_t* dp;
54 #endif
55 {
56 register Prefix_t* pfx = (Prefix_t*)dp;
57 register char* b;
58 register char* s;
59 register char* e;
60 register char* t;
61 register ssize_t w;
62 int skip;
63
64 skip = 0;
65 w = 0;
66 b = (char*)buf;
67 s = b;
68 e = s + n;
69 do
70 {
71 if (!(t = memchr(s, '\n', e - s)))
72 {
73 skip = 1;
74 t = e - 1;
75 }
76 n = t - s + 1;
77 if (pfx->skip)
78 pfx->skip = 0;
79 else
80 sfwr(f, pfx->prefix, n > 1 ? pfx->length : pfx->empty, dp);
81 w += sfwr(f, s, n, dp);
82 if ((s = t + 1) >= e)
83 return w;
84 } while ((s = t + 1) < e);
85 pfx->skip = skip;
86 return w;
87
88 }
89
90 /*
91 * remove the discipline on close
92 */
93
94 #if __STD_C
pfxexcept(Sfio_t * f,int type,Void_t * data,Sfdisc_t * dp)95 static int pfxexcept(Sfio_t* f, int type, Void_t* data, Sfdisc_t* dp)
96 #else
97 static int pfxexcept(f, type, data, dp)
98 Sfio_t* f;
99 int type;
100 Void_t* data;
101 Sfdisc_t* dp;
102 #endif
103 {
104 if (type == SF_FINAL || type == SF_DPOP)
105 free(dp);
106 return 0;
107 }
108
109 /*
110 * push the prefix discipline on f
111 */
112
113 #if __STD_C
sfdcprefix(Sfio_t * f,const char * prefix)114 int sfdcprefix(Sfio_t* f, const char* prefix)
115 #else
116 int sfdcprefix(f, prefix)
117 Sfio_t* f;
118 char* prefix;
119 #endif
120 {
121 register Prefix_t* pfx;
122 register char* s;
123 size_t n;
124
125 /*
126 * this is a writeonly discipline
127 */
128
129 if (!prefix || !(n = strlen(prefix)) || !(sfset(f, 0, 0) & SF_WRITE))
130 return -1;
131 if (!(pfx = (Prefix_t*)malloc(sizeof(Prefix_t) + n)))
132 return -1;
133 memset(pfx, 0, sizeof(*pfx));
134
135 pfx->disc.writef = pfxwrite;
136 pfx->disc.exceptf = pfxexcept;
137 pfx->length = n;
138 memcpy(pfx->prefix, prefix, n);
139 s = (char*)prefix + n;
140 while (--s > (char*)prefix && (*s == ' ' || *s == '\t'));
141 n = s - (char*)prefix;
142 if (*s != ' ' || *s != '\t')
143 n++;
144 pfx->empty = n;
145
146 if (sfdisc(f, &pfx->disc) != &pfx->disc)
147 {
148 free(pfx);
149 return -1;
150 }
151
152 return 0;
153 }
154