1 /*
2  * mc - columnate
3  *
4  * mc[-][-LINEWIDTH][-t][file...]
5  *	- causes break on colon
6  *	-LINEWIDTH sets width of line in which to columnate(default 80)
7  *	-t suppresses expanding multiple blanks into tabs
8  *
9  */
10 #include	<u.h>
11 #include	<sys/ioctl.h>
12 #include	<sys/termios.h>
13 #include	<libc.h>
14 #include	<draw.h>
15 #include	<bio.h>
16 
17 #define	WIDTH			80
18 #define	TAB	4
19 #define	WORD_ALLOC_QUANTA	1024
20 #define	ALLOC_QUANTA		4096
21 
22 int linewidth=WIDTH;
23 int colonflag=0;
24 int tabflag=0;	/* -t flag turned off forever */
25 Rune *cbuf, *cbufp;
26 Rune **word;
27 int maxwidth=0;
28 int nalloc=ALLOC_QUANTA;
29 int nwalloc=WORD_ALLOC_QUANTA;
30 int nchars=0;
31 int nwords=0;
32 Biobuf	bin;
33 Biobuf	bout;
34 
35 void getwidth(void), readbuf(int), error(char *);
36 void scanwords(void), columnate(void), morechars(void);
37 
38 void
39 main(int argc, char *argv[])
40 {
41 	int i;
42 	int lineset;
43 	int ifd;
44 
45 	lineset = 0;
46 	Binit(&bout, 1, OWRITE);
47 	while(argc > 1 && argv[1][0] == '-'){
48 		--argc; argv++;
49 		switch(argv[0][1]){
50 		case '\0':
51 			colonflag = 1;
52 			break;
53 		case 't':
54 			tabflag = 0;
55 			break;
56 		default:
57 			linewidth = atoi(&argv[0][1]);
58 			if(linewidth <= 1)
59 				linewidth = WIDTH;
60 			lineset = 1;
61 			break;
62 		}
63 	}
64 	if(lineset == 0)
65 		getwidth();
66 	cbuf = cbufp = malloc(ALLOC_QUANTA*(sizeof *cbuf));
67 	word = malloc(WORD_ALLOC_QUANTA*(sizeof *word));
68 	if(word == 0 || cbuf == 0)
69 		error("out of memory");
70 	if(argc == 1)
71 		readbuf(0);
72 	else{
73 		for(i = 1; i < argc; i++){
74 			if((ifd = open(*++argv, OREAD)) == -1)
75 				fprint(2, "mc: can't open %s (%r)\n", *argv);
76 			else{
77 				readbuf(ifd);
78 				Bflush(&bin);
79 				close(ifd);
80 			}
81 		}
82 	}
83 	columnate();
84 	exits(0);
85 }
86 void
87 error(char *s)
88 {
89 	fprint(2, "mc: %s\n", s);
90 	exits(s);
91 }
92 void
93 readbuf(int fd)
94 {
95 	int lastwascolon = 0;
96 	long c;
97 	int linesiz = 0;
98 
99 	Binit(&bin, fd, OREAD);
100 	do{
101 		if(nchars++ >= nalloc)
102 			morechars();
103 		*cbufp++ = c = Bgetrune(&bin);
104 		linesiz++;
105 		if(c == '\t') {
106 			cbufp[-1] = L' ';
107 			while(linesiz%TAB != 0) {
108 				if(nchars++ >= nalloc)
109 					morechars();
110 				*cbufp++ = L' ';
111 				linesiz++;
112 			}
113 		}
114 		if(colonflag && c == ':')
115 			lastwascolon++;
116 		else if(lastwascolon){
117 			if(c == '\n'){
118 				--nchars; 	/* skip newline */
119 				*cbufp = L'\0';
120 				while(nchars > 0 && cbuf[--nchars] != '\n')
121 					;
122 				if(nchars)
123 					nchars++;
124 				columnate();
125 				if (nchars)
126 					Bputc(&bout, '\n');
127 				Bprint(&bout, "%S", cbuf+nchars);
128 				nchars = 0;
129 				cbufp = cbuf;
130 			}
131 			lastwascolon = 0;
132 		}
133 		if(c == '\n')
134 			linesiz = 0;
135 	}while(c >= 0);
136 }
137 void
138 scanwords(void)
139 {
140 	Rune *p, *q;
141 	int i;
142 
143 	nwords=0;
144 	maxwidth=0;
145 	for(p = q = cbuf, i = 0; i < nchars; i++){
146 		if(*p++ == L'\n'){
147 			if(nwords >= nwalloc){
148 				nwalloc += WORD_ALLOC_QUANTA;
149 				if((word = realloc(word, nwalloc*sizeof(*word)))==0)
150 					error("out of memory");
151 			}
152 			word[nwords++] = q;
153 			p[-1] = L'\0';
154 			if(p-q > maxwidth)
155 				maxwidth = p-q;
156 			q = p;
157 		}
158 	}
159 }
160 
161 void
162 columnate(void)
163 {
164 	int i, j;
165 	int words_per_line;
166 	int nlines;
167 	int col;
168 	int endcol;
169 
170 
171 	scanwords();
172 	if(nwords==0)
173 		return;
174 	words_per_line = linewidth/maxwidth;
175 	if(words_per_line <= 0)
176 		words_per_line = 1;
177 	nlines=(nwords+words_per_line-1)/words_per_line;
178 	for(i = 0; i < nlines; i++){
179 		col = endcol = 0;
180 		for(j = i; j < nwords; j += nlines){
181 			endcol += maxwidth;
182 			Bprint(&bout, "%S", word[j]);
183 			col += word[j+1]-word[j]-1;
184 			if(j+nlines < nwords){
185 				if(tabflag) {
186 					int tabcol = (col|(TAB-1))+1;
187 					while(tabcol <= endcol){
188 						Bputc(&bout, '\t');
189 						col = tabcol;
190 						tabcol += TAB;
191 					}
192 				}
193 				while(col < endcol){
194 					Bputc(&bout, ' ');
195 					col++;
196 				}
197 			}
198 		}
199 		Bputc(&bout, '\n');
200 	}
201 }
202 
203 void
204 morechars(void)
205 {
206 	nalloc += ALLOC_QUANTA;
207 	if((cbuf = realloc(cbuf, nalloc*sizeof(*cbuf))) == 0)
208 		error("out of memory");
209 	cbufp = cbuf+nchars-1;
210 }
211 
212 /*
213  * These routines discover the width of the display.
214  * It takes some work.  If we do the easy calls to the
215  * draw library, the screen flashes due to repainting
216  * when mc exits.
217  */
218 
219 int
220 windowrect(struct winsize *ws)
221 {
222 	int tty;
223 
224 	if((tty = open("/dev/tty", OWRITE)) < 0)
225 		tty = 1;
226 
227 	if(ioctl(tty, TIOCGWINSZ, ws) < 0){
228 		if(tty != 1)
229 			close(tty);
230 		return -1;
231 	}
232 	if(tty != 1)
233 		close(tty);
234 	return 0;
235 }
236 
237 void
238 getwidth(void)
239 {
240 	struct winsize ws;
241 
242 	if(windowrect(&ws) < 0)
243 		return;
244 	linewidth = ws.ws_col;
245 }