1 /* GNUPLOT - termdoc.c */
2 
3 /*[
4  * Copyright 1986 - 1993, 1998, 2004   Thomas Williams, Colin Kelley
5  *
6  * Permission to use, copy, and distribute this software and its
7  * documentation for any purpose with or without fee is hereby granted,
8  * provided that the above copyright notice appear in all copies and
9  * that both that copyright notice and this permission notice appear
10  * in supporting documentation.
11  *
12  * Permission to modify the software is granted, but not the right to
13  * distribute the complete modified source code.  Modifications are to
14  * be distributed as patches to the released version.  Permission to
15  * distribute binaries produced by compiling modified sources is granted,
16  * provided you
17  *   1. distribute the corresponding source modifications from the
18  *    released version in the form of a patch file along with the binaries,
19  *   2. add special version identification to distinguish your version
20  *    in addition to the base release version number,
21  *   3. provide your name and address as the primary contact for the
22  *    support of your modified version, and
23  *   4. retain our contact information in regard to use of the base
24  *    software.
25  * Permission to distribute the released version of the source code along
26  * with corresponding source modifications in the form of a patch file is
27  * granted with same provisions 2 through 4 for binary distributions.
28  *
29  * This software is provided "as is" without express or implied warranty
30  * to the extent permitted by applicable law.
31 ]*/
32 
33 /*
34  * AUTHORS
35  *
36  *  David Denholm - 1996
37  */
38 
39 /* this file provides a replacement for fgets() which inserts all the
40  * help from the terminal drivers line by line at the < in the
41  * gnuplot.doc file. This way, doc2* dont need to know what's going
42  * on, and think it's all coming from one place.
43  *
44  * Can be compiled as a standalone program to generate the raw
45  * .doc test, when compiled with -DTEST_TERMDOC
46  *
47  * Strips comment lines {so none of doc2* need to bother}
48  * but magic comments beginning  C#  are used as markers
49  * for line number recording (as c compilers)
50  * We set BEGIN_HELP macro to "C#<driver>" as a special marker.
51  *
52  * Hmm - this is turning more and more into a preprocessor !
53  * gnuplot.doc now has multiple top-level entries, but
54  * some help systems (eg VMS) cannot tolerate this.
55  * As a complete bodge, conditional on TBOOLEAN single_top_level == TRUE,
56  * we accept only the first 1, and map any subsequent 1's to 2's
57  * At present, this leaves a bogus, empty section called
58  * commands, but that's a small price to pay to get it
59  * working properly
60  */
61 
62 #include "syscfg.h"
63 
64 #define DOCS_TERMDOC_MAIN
65 
66 #include "stdfn.h"
67 #include "gp_types.h"
68 #include "doc2x.h"
69 
70 /* because we hide details of including terminal drivers,
71  * we provide line numbers and file names
72  */
73 
74 int termdoc_lineno;
75 char termdoc_filename[80];
76 
77 TBOOLEAN single_top_level;
78 
79 char *
get_line(char * buffer,int max,FILE * fp)80 get_line( char *buffer, int max, FILE *fp)
81 {
82     static int line = -1;	/* not going yet */
83     static int level = 0;	/* terminals are at level 1 - we add this */
84     static int save_lineno;	/* for saving lineno */
85     static int seen_a_one = 0;
86 
87     if (line == -1) {
88 
89 	/* we are reading from file */
90 
91 	{
92 	  read_another_line:	/* come here if a comment is read */
93 
94 	    if (!fgets(buffer, max, fp))
95 		return NULL;	/* EOF */
96 	    ++termdoc_lineno;
97 	    if (buffer[0] == 'C') {
98 		if (buffer[1] == '#') {
99 		    /* should not happen in gnuplot.doc, but... */
100 		    safe_strncpy(termdoc_filename, buffer + 2, sizeof(termdoc_filename));
101 		    termdoc_filename[strlen(termdoc_filename) - 1] = NUL;
102 		    termdoc_lineno = 0;
103 		}
104 		goto read_another_line;		/* skip comments */
105 	    }
106 	}
107 
108 	if (single_top_level == TRUE) {
109 	    if (buffer[0] == '1') {
110 		if (seen_a_one) {
111 		    buffer[0] = '2';
112 		}
113 		seen_a_one = 1;
114 	    }
115 	}
116 	if (buffer[0] != '<')
117 	    return buffer;	/* the simple case */
118 
119 	/* prepare to return text from the terminal drivers */
120 	save_lineno = termdoc_lineno;
121 	termdoc_lineno = -1;	/* dont count the C# */
122 	level = buffer[1] - '1';
123 	line = 0;
124     }
125     /* we're sending lines from terminal help */
126 
127     /* process and skip comments. Note that the last line
128      * will invariably be a comment !
129      */
130 
131     while (termtext[line][0] == 'C') {
132 	if (termtext[line][1] == '#') {
133 	    safe_strncpy(termdoc_filename, termtext[line] + 2, sizeof(termdoc_filename));
134 	    termdoc_lineno = 0;
135 	}
136 	++termdoc_lineno;
137 
138 	if (!termtext[++line]) {
139 	    /* end of text : need to return a line from
140 	     * the file. Recursive call is best way out
141 	     */
142 	    termdoc_lineno = save_lineno;
143 	    /* we've done the last line, so get next line from file */
144 	    line = -1;
145 	    return get_line(buffer, max, fp);
146 	}
147     }
148 
149 
150     /* termtext[line] is the next line of text.
151      * more efficient to return pointer, but we need to modify it
152      */
153 
154     ++termdoc_lineno;
155     safe_strncpy(buffer, termtext[line], max);
156     /* dodgy; can overrun buffer; lh */
157     /* strncat(buffer, "\n", max); */
158     if (strlen(buffer) == (max - 1))
159         buffer[max-2] = '\n';
160     else
161         strcat(buffer, "\n");
162 
163     if (isdigit((int)buffer[0]))
164 	buffer[0] += level;
165 
166     if (!termtext[++line]) {
167 	/* end of terminal help : return to input file next time
168 	 * last (pseudo-)line in each terminal should be a comment,
169 	 * so we shouldn't get here, but...
170 	 */
171 	termdoc_lineno = save_lineno;
172 	/* we've done the last line, so get next line from file */
173 	line = -1;
174     }
175     return buffer;
176 }
177 
178 
179 /* Safe, '\0'-terminated version of strncpy()
180  * safe_strncpy(dest, src, n), where n = sizeof(dest)
181  * This is basically the old fit.c(copy_max) function
182  */
183 
184 char *
safe_strncpy(char * d,const char * s,size_t n)185 safe_strncpy( char *d, const char *s, size_t n)
186 {
187     char *ret;
188 
189     ret = strncpy(d, s, n);
190     if (strlen(s) >= n)
191         d[n-1] = NUL;
192 
193     return ret;
194 }
195 
196 
197 #ifdef TEST_TERMDOC
198 int
main()199 main()
200 {
201     char line[256];
202 
203     while (get_line(line, sizeof(line), stdin))
204 	printf("%s:%d:%s", termdoc_filename, termdoc_lineno, line);
205     return 0;
206 }
207 #endif
208