1 /***********************************************************************
2 *                                                                      *
3 *               This software is part of the ast package               *
4 *          Copyright (c) 1985-2011 AT&T Intellectual Property          *
5 *                      and is licensed under the                       *
6 *                 Eclipse Public License, Version 1.0                  *
7 *                    by AT&T Intellectual Property                     *
8 *                                                                      *
9 *                A copy of the License is available at                 *
10 *          http://www.eclipse.org/org/documents/epl-v10.html           *
11 *         (with md5 checksum b35adb5213ca9657e911e9befb180842)         *
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 #pragma prototyped
23 /*
24  * Glenn Fowler
25  * AT&T Research
26  *
27  * return an Sfio_t* to a file or string that
28  *
29  *	splices \\n to single lines
30  *	checks for "..." and '...' spanning newlines
31  *	drops #...\n comments
32  *
33  * if <arg> is a file and first line matches
34  *	#!!! <level> <message> !!!
35  * then error(<lev>,"%s: %s",<arg>,<msg>) called
36  *
37  * NOTE: seek disabled and string disciplines cannot be composed
38  *	 quoted \n translated to \r
39  */
40 
41 #include <ast.h>
42 #include <error.h>
43 #include <tok.h>
44 
45 typedef struct
46 {
47 	Sfdisc_t	disc;
48 	Sfio_t*		sp;
49 	int		quote;
50 	int*		line;
51 } Splice_t;
52 
53 /*
54  * the splicer
55  */
56 
57 static int
spliceline(Sfio_t * s,int op,void * val,Sfdisc_t * ad)58 spliceline(Sfio_t* s, int op, void* val, Sfdisc_t* ad)
59 {
60 	Splice_t*	d = (Splice_t*)ad;
61 	register char*	b;
62 	register int	c;
63 	register int	n;
64 	register int	q;
65 	register int	j;
66 	register char*	e;
67 	char*		buf;
68 
69 	NoP(val);
70 	switch (op)
71 	{
72 	case SF_CLOSING:
73 		sfclose(d->sp);
74 		return 0;
75 	case SF_DPOP:
76 		free(d);
77 		return 0;
78 	case SF_READ:
79 		do
80 		{
81 			if (!(buf = sfgetr(d->sp, '\n', 0)) && !(buf = sfgetr(d->sp, '\n', -1)))
82 				return 0;
83 			n = sfvalue(d->sp);
84 			q = d->quote;
85 			j = 0;
86 			(*d->line)++;
87 			if (n > 1 && buf[n - 2] == '\\')
88 			{
89 				j = 1;
90 				n -= 2;
91 				if (q == '#')
92 				{
93 					n = 0;
94 					continue;
95 				}
96 			}
97 			else if (q == '#')
98 			{
99 				q = 0;
100 				n = 0;
101 				continue;
102 			}
103 			if (n > 0)
104 			{
105 				e = (b = buf) + n;
106 				while (b < e)
107 				{
108 					if ((c = *b++) == '\\')
109 						b++;
110 					else if (c == q)
111 						q = 0;
112 					else if (!q)
113 					{
114 						if (c == '\'' || c == '"')
115 							q = c;
116 						else if (c == '#' && (b == (buf + 1) || (c = *(b - 2)) == ' ' || c == '\t'))
117 						{
118 							if (buf[n - 1] != '\n')
119 							{
120 								q = '#';
121 								n = b - buf - 2;
122 							}
123 							else if (n = b - buf - 1)
124 								buf[n - 1] = '\n';
125 							break;
126 						}
127 					}
128 				}
129 				if (n > 0)
130 				{
131 					if (!j && buf[n - 1] != '\n' && (s->_flags & SF_STRING))
132 						buf[n++] = '\n';
133 					if (q && buf[n - 1] == '\n')
134 						buf[n - 1] = '\r';
135 				}
136 			}
137 		} while (n <= 0);
138 		sfsetbuf(s, buf, n);
139 		d->quote = q;
140 		return 1;
141 	default:
142 		return 0;
143 	}
144 }
145 
146 /*
147  * open a stream to parse lines
148  *
149  *	flags: 0		arg: open Sfio_t*
150  *	flags: SF_READ		arg: file name
151  *	flags: SF_STRING	arg: null terminated char*
152  *
153  * if line!=0 then it points to a line count that starts at 0
154  * and is incremented for each input line
155  */
156 
157 Sfio_t*
tokline(const char * arg,int flags,int * line)158 tokline(const char* arg, int flags, int* line)
159 {
160 	Sfio_t*		f;
161 	Sfio_t*		s;
162 	Splice_t*	d;
163 	char*		p;
164 	char*		e;
165 
166 	static int	hidden;
167 
168 	if (!(d = newof(0, Splice_t, 1, 0)))
169 		return 0;
170 	if (!(s = sfopen(NiL, NiL, "s")))
171 	{
172 		free(d);
173 		return 0;
174 	}
175 	if (!(flags & (SF_STRING|SF_READ)))
176 		f = (Sfio_t*)arg;
177 	else if (!(f = sfopen(NiL, arg, (flags & SF_STRING) ? "s" : "r")))
178 	{
179 		free(d);
180 		sfclose(s);
181 		return 0;
182 	}
183 	else if ((p = sfreserve(f, 0, 0)) && sfvalue(f) > 11 && strmatch(p, "#!!! +([-0-9]) *([!\n]) !!!\n*") && (e = strchr(p, '\n')))
184 	{
185 		flags = strtol(p + 5, &p, 10);
186 		error(flags, "%s:%-.*s", arg, e - p - 4, p);
187 	}
188 	d->disc.exceptf = spliceline;
189 	d->sp = f;
190 	*(d->line = line ? line : &hidden) = 0;
191 	sfdisc(s, (Sfdisc_t*)d);
192 	return s;
193 }
194