1 47d4646e 2020-05-05 rsc #include "rc.h"
  2 47d4646e 2020-05-05 rsc #include "io.h"
  3 47d4646e 2020-05-05 rsc #include "fns.h"
  4 47d4646e 2020-05-05 rsc 
  5 47d4646e 2020-05-05 rsc static tree*	body(int tok, int *ptok);
  6 47d4646e 2020-05-05 rsc static tree*	brace(int tok);
  7 47d4646e 2020-05-05 rsc static tree*	cmd(int tok, int *ptok);
  8 47d4646e 2020-05-05 rsc static tree*	cmd2(int tok, int *ptok);
  9 47d4646e 2020-05-05 rsc static tree*	cmd3(int tok, int *ptok);
 10 47d4646e 2020-05-05 rsc static tree*	cmds(int tok, int *ptok, int nlok);
 11 47d4646e 2020-05-05 rsc static tree*	epilog(int tok, int *ptok);
 12 47d4646e 2020-05-05 rsc static int	iswordtok(int tok);
 13 47d4646e 2020-05-05 rsc static tree*	line(int tok, int *ptok);
 14 47d4646e 2020-05-05 rsc static tree*	paren(int tok);
 15 47d4646e 2020-05-05 rsc static tree*	yyredir(int tok, int *ptok);
 16 ff74f7cd 2020-05-05 rsc static tree*	yyword(int tok, int *ptok, int eqok);
 17 47d4646e 2020-05-05 rsc static tree*	word1(int tok, int *ptok);
 18 47d4646e 2020-05-05 rsc static tree*	words(int tok, int *ptok);
 19 47d4646e 2020-05-05 rsc 
 20 47d4646e 2020-05-05 rsc static jmp_buf yyjmp;
 21 47d4646e 2020-05-05 rsc 
 22 3caf5c23 2020-05-05 rsc static int
 23 3caf5c23 2020-05-05 rsc dropnl(int tok)
 24 3caf5c23 2020-05-05 rsc {
 25 7d6a248f 2020-05-05 rsc 	while(tok == ' ' || tok == '\n')
 26 3caf5c23 2020-05-05 rsc 		tok = yylex();
 27 3caf5c23 2020-05-05 rsc 	return tok;
 28 3caf5c23 2020-05-05 rsc }
 29 3caf5c23 2020-05-05 rsc 
 30 7d6a248f 2020-05-05 rsc static int
 31 7d6a248f 2020-05-05 rsc dropsp(int tok)
 32 7d6a248f 2020-05-05 rsc {
 33 7d6a248f 2020-05-05 rsc 	while(tok == ' ')
 34 7d6a248f 2020-05-05 rsc 		tok = yylex();
 35 7d6a248f 2020-05-05 rsc 	return tok;
 36 7d6a248f 2020-05-05 rsc }
 37 7d6a248f 2020-05-05 rsc 
 38 47d4646e 2020-05-05 rsc static void
 39 47d4646e 2020-05-05 rsc syntax(int tok)
 40 47d4646e 2020-05-05 rsc {
 41 601e07b6 2020-05-05 rsc 	USED(tok);
 42 601e07b6 2020-05-05 rsc 	yyerror("syntax error");
 43 47d4646e 2020-05-05 rsc 	longjmp(yyjmp, 1);
 44 47d4646e 2020-05-05 rsc }
 45 47d4646e 2020-05-05 rsc 
 46 47d4646e 2020-05-05 rsc int
 47 47d4646e 2020-05-05 rsc parse(void)
 48 47d4646e 2020-05-05 rsc {
 49 47d4646e 2020-05-05 rsc 	tree *t;
 50 47d4646e 2020-05-05 rsc 	int tok;
 51 47d4646e 2020-05-05 rsc 
 52 47d4646e 2020-05-05 rsc 	if(setjmp(yyjmp))
 53 47d4646e 2020-05-05 rsc 		return 1;
 54 47d4646e 2020-05-05 rsc 
 55 47d4646e 2020-05-05 rsc 	// rc:				{ return 1;}
 56 47d4646e 2020-05-05 rsc 	// |	line '\n'		{return !compile($1);}
 57 47d4646e 2020-05-05 rsc 
 58 7d6a248f 2020-05-05 rsc 	tok = dropsp(yylex());
 59 47d4646e 2020-05-05 rsc 	if(tok == EOF)
 60 47d4646e 2020-05-05 rsc 		return 1;
 61 47d4646e 2020-05-05 rsc 	t = line(tok, &tok);
 62 47d4646e 2020-05-05 rsc 	if(tok != '\n')
 63 47d4646e 2020-05-05 rsc 		yyerror("missing newline at end of line");
 64 47d4646e 2020-05-05 rsc 	yylval.tree = t;
 65 47d4646e 2020-05-05 rsc 	return !compile(t);
 66 47d4646e 2020-05-05 rsc }
 67 47d4646e 2020-05-05 rsc 
 68 47d4646e 2020-05-05 rsc static tree*
 69 47d4646e 2020-05-05 rsc line(int tok, int *ptok)
 70 47d4646e 2020-05-05 rsc {
 71 47d4646e 2020-05-05 rsc 	return cmds(tok, ptok, 0);
 72 47d4646e 2020-05-05 rsc }
 73 47d4646e 2020-05-05 rsc 
 74 47d4646e 2020-05-05 rsc static tree*
 75 47d4646e 2020-05-05 rsc body(int tok, int *ptok)
 76 47d4646e 2020-05-05 rsc {
 77 47d4646e 2020-05-05 rsc 	return cmds(tok, ptok, 1);
 78 47d4646e 2020-05-05 rsc }
 79 47d4646e 2020-05-05 rsc 
 80 47d4646e 2020-05-05 rsc static tree*
 81 47d4646e 2020-05-05 rsc cmds(int tok, int *ptok, int nlok)
 82 47d4646e 2020-05-05 rsc {
 83 47d4646e 2020-05-05 rsc 	tree *t, **last, *t2;
 84 47d4646e 2020-05-05 rsc 
 85 47d4646e 2020-05-05 rsc 	// line:	cmd
 86 47d4646e 2020-05-05 rsc 	// |	cmdsa line		{$$=tree2(';', $1, $2);}
 87 47d4646e 2020-05-05 rsc 	// cmdsa:	cmd ';'
 88 47d4646e 2020-05-05 rsc 	// |	cmd '&'			{$$=tree1('&', $1);}
 89 47d4646e 2020-05-05 rsc 
 90 47d4646e 2020-05-05 rsc 	// body:	cmd
 91 47d4646e 2020-05-05 rsc 	// |	cmdsan body		{$$=tree2(';', $1, $2);}
 92 47d4646e 2020-05-05 rsc 	// cmdsan:	cmdsa
 93 47d4646e 2020-05-05 rsc 	// |	cmd '\n'
 94 47d4646e 2020-05-05 rsc 
 95 47d4646e 2020-05-05 rsc 	t = nil;
 96 47d4646e 2020-05-05 rsc 	last = nil;
 97 47d4646e 2020-05-05 rsc 	for(;;) {
 98 47d4646e 2020-05-05 rsc 		t2 = cmd(tok, &tok);
 99 47d4646e 2020-05-05 rsc 		if(tok == '&')
100 47d4646e 2020-05-05 rsc 			t2 = tree1('&', t2);
101 47d4646e 2020-05-05 rsc 		if(t2 != nil) {
102 47d4646e 2020-05-05 rsc 			// slot into list t
103 47d4646e 2020-05-05 rsc 			if(last == nil) {
104 47d4646e 2020-05-05 rsc 				t = t2;
105 47d4646e 2020-05-05 rsc 				last = &t;
106 47d4646e 2020-05-05 rsc 			} else {
107 47d4646e 2020-05-05 rsc 				*last = tree2(';', *last, t2);
108 47d4646e 2020-05-05 rsc 				last = &(*last)->child[1];
109 47d4646e 2020-05-05 rsc 			}
110 47d4646e 2020-05-05 rsc 		}
111 47d4646e 2020-05-05 rsc 		if(tok != ';' && tok != '&' && (!nlok || tok != '\n'))
112 47d4646e 2020-05-05 rsc 			break;
113 47d4646e 2020-05-05 rsc 		tok = yylex();
114 47d4646e 2020-05-05 rsc 	}
115 47d4646e 2020-05-05 rsc 	*ptok = tok;
116 47d4646e 2020-05-05 rsc 	return t;
117 47d4646e 2020-05-05 rsc }
118 47d4646e 2020-05-05 rsc 
119 47d4646e 2020-05-05 rsc static tree*
120 47d4646e 2020-05-05 rsc brace(int tok)
121 47d4646e 2020-05-05 rsc {
122 47d4646e 2020-05-05 rsc 	tree *t;
123 47d4646e 2020-05-05 rsc 
124 47d4646e 2020-05-05 rsc 	// brace:	'{' body '}'		{$$=tree1(BRACE, $2);}
125 47d4646e 2020-05-05 rsc 
126 7d6a248f 2020-05-05 rsc 	tok = dropsp(tok);
127 47d4646e 2020-05-05 rsc 	if(tok != '{')
128 47d4646e 2020-05-05 rsc 		syntax(tok);
129 47d4646e 2020-05-05 rsc 	t = body(yylex(), &tok);
130 47d4646e 2020-05-05 rsc 	if(tok != '}')
131 47d4646e 2020-05-05 rsc 		syntax(tok);
132 47d4646e 2020-05-05 rsc 	return tree1(BRACE, t);
133 47d4646e 2020-05-05 rsc }
134 47d4646e 2020-05-05 rsc 
135 47d4646e 2020-05-05 rsc static tree*
136 47d4646e 2020-05-05 rsc paren(int tok)
137 47d4646e 2020-05-05 rsc {
138 47d4646e 2020-05-05 rsc 	tree *t;
139 47d4646e 2020-05-05 rsc 
140 47d4646e 2020-05-05 rsc 	// paren:	'(' body ')'		{$$=tree1(PCMD, $2);}
141 47d4646e 2020-05-05 rsc 
142 7d6a248f 2020-05-05 rsc 	tok = dropsp(tok);
143 47d4646e 2020-05-05 rsc 	if(tok != '(')
144 47d4646e 2020-05-05 rsc 		syntax(tok);
145 47d4646e 2020-05-05 rsc 	t = body(yylex(), &tok);
146 47d4646e 2020-05-05 rsc 	if(tok != ')')
147 47d4646e 2020-05-05 rsc 		syntax(tok);
148 47d4646e 2020-05-05 rsc 	return tree1(PCMD, t);
149 47d4646e 2020-05-05 rsc }
150 47d4646e 2020-05-05 rsc 
151 47d4646e 2020-05-05 rsc static tree*
152 47d4646e 2020-05-05 rsc epilog(int tok, int *ptok)
153 47d4646e 2020-05-05 rsc {
154 47d4646e 2020-05-05 rsc 	tree *t, *r;
155 47d4646e 2020-05-05 rsc 
156 47d4646e 2020-05-05 rsc 	// epilog:				{$$=0;}
157 47d4646e 2020-05-05 rsc 	// |	redir epilog		{$$=mung2($1, $1->child[0], $2);}
158 47d4646e 2020-05-05 rsc 
159 47d4646e 2020-05-05 rsc 	if(tok != REDIR && tok != DUP) {
160 47d4646e 2020-05-05 rsc 		*ptok = tok;
161 47d4646e 2020-05-05 rsc 		return nil;
162 47d4646e 2020-05-05 rsc 	}
163 47d4646e 2020-05-05 rsc 
164 47d4646e 2020-05-05 rsc 	r = yyredir(tok, &tok);
165 47d4646e 2020-05-05 rsc 	t = epilog(tok, &tok);
166 47d4646e 2020-05-05 rsc 	*ptok = tok;
167 47d4646e 2020-05-05 rsc 	return mung2(r, r->child[0], t);
168 47d4646e 2020-05-05 rsc }
169 47d4646e 2020-05-05 rsc 
170 47d4646e 2020-05-05 rsc static tree*
171 47d4646e 2020-05-05 rsc yyredir(int tok, int *ptok)
172 47d4646e 2020-05-05 rsc {
173 47d4646e 2020-05-05 rsc 	tree *r, *w;
174 47d4646e 2020-05-05 rsc 
175 47d4646e 2020-05-05 rsc 	// redir:	REDIR word		{$$=mung1($1, $1->rtype==HERE?heredoc($2):$2);}
176 47d4646e 2020-05-05 rsc 	// |	DUP
177 47d4646e 2020-05-05 rsc 
178 47d4646e 2020-05-05 rsc 	switch(tok) {
179 47d4646e 2020-05-05 rsc 	default:
180 47d4646e 2020-05-05 rsc 		syntax(tok);
181 47d4646e 2020-05-05 rsc 	case DUP:
182 47d4646e 2020-05-05 rsc 		r = yylval.tree;
183 7d6a248f 2020-05-05 rsc 		*ptok = dropsp(yylex());
184 47d4646e 2020-05-05 rsc 		break;
185 47d4646e 2020-05-05 rsc 	case REDIR:
186 47d4646e 2020-05-05 rsc 		r = yylval.tree;
187 ff74f7cd 2020-05-05 rsc 		w = yyword(yylex(), &tok, 1);
188 7d6a248f 2020-05-05 rsc 		*ptok = dropsp(tok);
189 47d4646e 2020-05-05 rsc 		r = mung1(r, r->rtype==HERE?heredoc(w):w);
190 47d4646e 2020-05-05 rsc 		break;
191 47d4646e 2020-05-05 rsc 	}
192 47d4646e 2020-05-05 rsc 	return r;
193 47d4646e 2020-05-05 rsc }
194 47d4646e 2020-05-05 rsc 
195 47d4646e 2020-05-05 rsc static tree*
196 47d4646e 2020-05-05 rsc cmd(int tok, int *ptok)
197 47d4646e 2020-05-05 rsc {
198 7d6a248f 2020-05-05 rsc 	int op;
199 7d6a248f 2020-05-05 rsc 	tree *t1, *t2;
200 7d6a248f 2020-05-05 rsc 
201 7d6a248f 2020-05-05 rsc 	// |	cmd ANDAND cmd		{$$=tree2(ANDAND, $1, $3);}
202 7d6a248f 2020-05-05 rsc 	// |	cmd OROR cmd		{$$=tree2(OROR, $1, $3);}
203 7d6a248f 2020-05-05 rsc 
204 601e07b6 2020-05-05 rsc 	tok = dropsp(tok);
205 601e07b6 2020-05-05 rsc 	t1 = cmd2(tok, &tok);
206 7d6a248f 2020-05-05 rsc 	while(tok == ANDAND || tok == OROR) {
207 7d6a248f 2020-05-05 rsc 		op = tok;
208 601e07b6 2020-05-05 rsc 		t2 = cmd2(dropnl(yylex()), &tok);
209 7d6a248f 2020-05-05 rsc 		t1 = tree2(op, t1, t2);
210 7d6a248f 2020-05-05 rsc 	}
211 7d6a248f 2020-05-05 rsc 	*ptok = tok;
212 7d6a248f 2020-05-05 rsc 	return t1;
213 7d6a248f 2020-05-05 rsc }
214 7d6a248f 2020-05-05 rsc 
215 7d6a248f 2020-05-05 rsc static tree*
216 601e07b6 2020-05-05 rsc cmd2(int tok, int *ptok)
217 7d6a248f 2020-05-05 rsc {
218 7d6a248f 2020-05-05 rsc 	tree *t1, *t2, *t3;
219 7d6a248f 2020-05-05 rsc 
220 7d6a248f 2020-05-05 rsc 	// |	cmd PIPE cmd		{$$=mung2($2, $1, $3);}
221 601e07b6 2020-05-05 rsc 	t1 = cmd3(tok, &tok);
222 7d6a248f 2020-05-05 rsc 	while(tok == PIPE) {
223 7d6a248f 2020-05-05 rsc 		t2 = yylval.tree;
224 601e07b6 2020-05-05 rsc 		t3 = cmd3(dropnl(yylex()), &tok);
225 7d6a248f 2020-05-05 rsc 		t1 = mung2(t2, t1, t3);
226 7d6a248f 2020-05-05 rsc 	}
227 7d6a248f 2020-05-05 rsc 	*ptok = tok;
228 7d6a248f 2020-05-05 rsc 	return t1;
229 7d6a248f 2020-05-05 rsc }
230 7d6a248f 2020-05-05 rsc 
231 7d6a248f 2020-05-05 rsc static tree*
232 601e07b6 2020-05-05 rsc cmd3(int tok, int *ptok)
233 7d6a248f 2020-05-05 rsc {
234 7d6a248f 2020-05-05 rsc 	tree *t1, *t2, *t3, *t4;
235 7d6a248f 2020-05-05 rsc 
236 7d6a248f 2020-05-05 rsc 	tok = dropsp(tok);
237 7d6a248f 2020-05-05 rsc 	switch(tok) {
238 7d6a248f 2020-05-05 rsc 	case ';':
239 7d6a248f 2020-05-05 rsc 	case '&':
240 7d6a248f 2020-05-05 rsc 	case '\n':
241 7d6a248f 2020-05-05 rsc 		*ptok = tok;
242 7d6a248f 2020-05-05 rsc 		return nil;
243 7d6a248f 2020-05-05 rsc 
244 47d4646e 2020-05-05 rsc 	case IF:
245 47d4646e 2020-05-05 rsc 		// |	IF paren {skipnl();} cmd	{$$=mung2($1, $2, $4);}
246 47d4646e 2020-05-05 rsc 		// |	IF NOT {skipnl();} cmd	{$$=mung1($2, $4);}
247 47d4646e 2020-05-05 rsc 		t1 = yylval.tree;
248 7d6a248f 2020-05-05 rsc 		tok = dropsp(yylex());
249 47d4646e 2020-05-05 rsc 		if(tok == NOT) {
250 47d4646e 2020-05-05 rsc 			t1 = yylval.tree;
251 3caf5c23 2020-05-05 rsc 			t2 = cmd(dropnl(yylex()), ptok);
252 47d4646e 2020-05-05 rsc 			return mung1(t1, t2);
253 47d4646e 2020-05-05 rsc 		}
254 47d4646e 2020-05-05 rsc 		t2 = paren(tok);
255 3caf5c23 2020-05-05 rsc 		t3 = cmd(dropnl(yylex()), ptok);
256 47d4646e 2020-05-05 rsc 		return mung2(t1, t2, t3);
257 47d4646e 2020-05-05 rsc 
258 47d4646e 2020-05-05 rsc 	case FOR:
259 47d4646e 2020-05-05 rsc 		// |	FOR '(' word IN words ')' {skipnl();} cmd
260 47d4646e 2020-05-05 rsc 		//		{$$=mung3($1, $3, $5 ? $5 : tree1(PAREN, $5), $8);}
261 47d4646e 2020-05-05 rsc 		// |	FOR '(' word ')' {skipnl();} cmd
262 47d4646e 2020-05-05 rsc 		//		{$$=mung3($1, $3, (tree *)0, $6);}
263 47d4646e 2020-05-05 rsc 		t1 = yylval.tree;
264 7d6a248f 2020-05-05 rsc 		tok = dropsp(yylex());
265 47d4646e 2020-05-05 rsc 		if(tok != '(')
266 47d4646e 2020-05-05 rsc 			syntax(tok);
267 ff74f7cd 2020-05-05 rsc 		t2 = yyword(yylex(), &tok, 1);
268 47d4646e 2020-05-05 rsc 		switch(tok) {
269 47d4646e 2020-05-05 rsc 		default:
270 47d4646e 2020-05-05 rsc 			syntax(tok);
271 47d4646e 2020-05-05 rsc 		case ')':
272 47d4646e 2020-05-05 rsc 			t3 = nil;
273 47d4646e 2020-05-05 rsc 			break;
274 47d4646e 2020-05-05 rsc 		case IN:
275 47d4646e 2020-05-05 rsc 			t3 = words(yylex(), &tok);
276 47d4646e 2020-05-05 rsc 			if(t3 == nil)
277 47d4646e 2020-05-05 rsc 				t3 = tree1(PAREN, nil);
278 47d4646e 2020-05-05 rsc 			if(tok != ')')
279 47d4646e 2020-05-05 rsc 				syntax(tok);
280 47d4646e 2020-05-05 rsc 			break;
281 47d4646e 2020-05-05 rsc 		}
282 3caf5c23 2020-05-05 rsc 		t4 = cmd(dropnl(yylex()), ptok);
283 47d4646e 2020-05-05 rsc 		return mung3(t1, t2, t3, t4);
284 47d4646e 2020-05-05 rsc 
285 47d4646e 2020-05-05 rsc 	case WHILE:
286 47d4646e 2020-05-05 rsc 		// |	WHILE paren {skipnl();} cmd
287 47d4646e 2020-05-05 rsc 		//		{$$=mung2($1, $2, $4);}
288 47d4646e 2020-05-05 rsc 		t1 = yylval.tree;
289 47d4646e 2020-05-05 rsc 		t2 = paren(yylex());
290 3caf5c23 2020-05-05 rsc 		t3 = cmd(dropnl(yylex()), ptok);
291 47d4646e 2020-05-05 rsc 		return mung2(t1, t2, t3);
292 47d4646e 2020-05-05 rsc 
293 47d4646e 2020-05-05 rsc 	case SWITCH:
294 47d4646e 2020-05-05 rsc 		// |	SWITCH word {skipnl();} brace
295 47d4646e 2020-05-05 rsc 		//		{$$=tree2(SWITCH, $2, $4);}
296 ff74f7cd 2020-05-05 rsc 		t1 = yyword(yylex(), &tok, 1);
297 3caf5c23 2020-05-05 rsc 		tok = dropnl(tok); // doesn't work in yacc grammar but works here!
298 47d4646e 2020-05-05 rsc 		t2 = brace(tok);
299 7d6a248f 2020-05-05 rsc 		*ptok = dropsp(yylex());
300 47d4646e 2020-05-05 rsc 		return tree2(SWITCH, t1, t2);
301 47d4646e 2020-05-05 rsc 
302 47d4646e 2020-05-05 rsc 	case FN:
303 47d4646e 2020-05-05 rsc 		// |	FN words brace		{$$=tree2(FN, $2, $3);}
304 47d4646e 2020-05-05 rsc 		// |	FN words		{$$=tree1(FN, $2);}
305 47d4646e 2020-05-05 rsc 		t1 = words(yylex(), &tok);
306 47d4646e 2020-05-05 rsc 		if(tok != '{') {
307 47d4646e 2020-05-05 rsc 			*ptok = tok;
308 47d4646e 2020-05-05 rsc 			return tree1(FN, t1);
309 47d4646e 2020-05-05 rsc 		}
310 47d4646e 2020-05-05 rsc 		t2 = brace(tok);
311 7d6a248f 2020-05-05 rsc 		*ptok = dropsp(yylex());
312 47d4646e 2020-05-05 rsc 		return tree2(FN, t1, t2);
313 47d4646e 2020-05-05 rsc 
314 47d4646e 2020-05-05 rsc 	case TWIDDLE:
315 47d4646e 2020-05-05 rsc 		// |	TWIDDLE word words	{$$=mung2($1, $2, $3);}
316 47d4646e 2020-05-05 rsc 		t1 = yylval.tree;
317 ff74f7cd 2020-05-05 rsc 		t2 = yyword(yylex(), &tok, 1);
318 47d4646e 2020-05-05 rsc 		t3 = words(tok, ptok);
319 47d4646e 2020-05-05 rsc 		return mung2(t1, t2, t3);
320 47d4646e 2020-05-05 rsc 
321 47d4646e 2020-05-05 rsc 	case BANG:
322 47d4646e 2020-05-05 rsc 	case SUBSHELL:
323 47d4646e 2020-05-05 rsc 		// |	BANG cmd		{$$=mung1($1, $2);}
324 47d4646e 2020-05-05 rsc 		// |	SUBSHELL cmd		{$$=mung1($1, $2);}
325 601e07b6 2020-05-05 rsc 		// Note: cmd2: ! x | y is !{x | y} not {!x} | y.
326 47d4646e 2020-05-05 rsc 		t1 = yylval.tree;
327 601e07b6 2020-05-05 rsc 		return mung1(t1, cmd2(yylex(), ptok));
328 47d4646e 2020-05-05 rsc 
329 47d4646e 2020-05-05 rsc 	case REDIR:
330 47d4646e 2020-05-05 rsc 	case DUP:
331 47d4646e 2020-05-05 rsc 		// |	redir cmd  %prec BANG	{$$=mung2($1, $1->child[0], $2);}
332 601e07b6 2020-05-05 rsc 		// Note: cmd2: {>x echo a | tr a-z A-Z} writes A to x.
333 47d4646e 2020-05-05 rsc 		t1 = yyredir(tok, &tok);
334 601e07b6 2020-05-05 rsc 		t2 = cmd2(tok, ptok);
335 47d4646e 2020-05-05 rsc 		return mung2(t1, t1->child[0], t2);
336 47d4646e 2020-05-05 rsc 
337 47d4646e 2020-05-05 rsc 	case '{':
338 47d4646e 2020-05-05 rsc 		// |	brace epilog		{$$=epimung($1, $2);}
339 47d4646e 2020-05-05 rsc 		t1 = brace(tok);
340 7d6a248f 2020-05-05 rsc 		tok = dropsp(yylex());
341 47d4646e 2020-05-05 rsc 		t2 = epilog(tok, ptok);
342 47d4646e 2020-05-05 rsc 		return epimung(t1, t2);
343 47d4646e 2020-05-05 rsc 	}
344 47d4646e 2020-05-05 rsc 
345 47d4646e 2020-05-05 rsc 	if(!iswordtok(tok)) {
346 47d4646e 2020-05-05 rsc 		*ptok = tok;
347 47d4646e 2020-05-05 rsc 		return nil;
348 47d4646e 2020-05-05 rsc 	}
349 47d4646e 2020-05-05 rsc 
350 47d4646e 2020-05-05 rsc 	// cmd: ...
351 47d4646e 2020-05-05 rsc 	// |	simple			{$$=simplemung($1);}
352 47d4646e 2020-05-05 rsc 	// |	assign cmd %prec BANG	{$$=mung3($1, $1->child[0], $1->child[1], $2);}
353 47d4646e 2020-05-05 rsc 	// assign:	first '=' word		{$$=tree2('=', $1, $3);}
354 47d4646e 2020-05-05 rsc 	// Note: first is same as word except for disallowing all the leading keywords,
355 47d4646e 2020-05-05 rsc 	// but all those keywords have been picked off in the switch above.
356 47d4646e 2020-05-05 rsc 	// Except NOT, but disallowing that in yacc was likely a mistake anyway:
357 47d4646e 2020-05-05 rsc 	// there's no ambiguity in not=1 or not x y z.
358 ff74f7cd 2020-05-05 rsc 	t1 = yyword(tok, &tok, 0);
359 47d4646e 2020-05-05 rsc 	if(tok == '=') {
360 47d4646e 2020-05-05 rsc 		// assignment
361 601e07b6 2020-05-05 rsc 		// Note: cmd2: {x=1 true | echo $x} echoes 1.
362 ff74f7cd 2020-05-05 rsc 		t1 = tree2('=', t1, yyword(yylex(), &tok, 1));
363 601e07b6 2020-05-05 rsc 		t2 = cmd2(tok, ptok);
364 47d4646e 2020-05-05 rsc 		return mung3(t1, t1->child[0], t1->child[1], t2);
365 47d4646e 2020-05-05 rsc 	}
366 47d4646e 2020-05-05 rsc 
367 47d4646e 2020-05-05 rsc 	// simple:	first
368 47d4646e 2020-05-05 rsc 	// |	simple word		{$$=tree2(ARGLIST, $1, $2);}
369 47d4646e 2020-05-05 rsc 	// |	simple redir		{$$=tree2(ARGLIST, $1, $2);}
370 47d4646e 2020-05-05 rsc 	for(;;) {
371 47d4646e 2020-05-05 rsc 		if(tok == REDIR || tok == DUP) {
372 47d4646e 2020-05-05 rsc 			t1 = tree2(ARGLIST, t1, yyredir(tok, &tok));
373 47d4646e 2020-05-05 rsc 		} else if(iswordtok(tok)) {
374 ff74f7cd 2020-05-05 rsc 			t1 = tree2(ARGLIST, t1, yyword(tok, &tok, 1));
375 47d4646e 2020-05-05 rsc 		} else {
376 47d4646e 2020-05-05 rsc 			break;
377 47d4646e 2020-05-05 rsc 		}
378 47d4646e 2020-05-05 rsc 	}
379 47d4646e 2020-05-05 rsc 	*ptok = tok;
380 47d4646e 2020-05-05 rsc 	return simplemung(t1);
381 47d4646e 2020-05-05 rsc }
382 47d4646e 2020-05-05 rsc 
383 47d4646e 2020-05-05 rsc static tree*
384 47d4646e 2020-05-05 rsc words(int tok, int *ptok)
385 47d4646e 2020-05-05 rsc {
386 47d4646e 2020-05-05 rsc 	tree *t;
387 47d4646e 2020-05-05 rsc 
388 47d4646e 2020-05-05 rsc 	// words:				{$$=(tree*)0;}
389 47d4646e 2020-05-05 rsc 	// |	words word		{$$=tree2(WORDS, $1, $2);}
390 47d4646e 2020-05-05 rsc 
391 47d4646e 2020-05-05 rsc 	t = nil;
392 7d6a248f 2020-05-05 rsc 	tok = dropsp(tok);
393 47d4646e 2020-05-05 rsc 	while(iswordtok(tok))
394 ff74f7cd 2020-05-05 rsc 		t = tree2(WORDS, t, yyword(tok, &tok, 1));
395 47d4646e 2020-05-05 rsc 	*ptok = tok;
396 47d4646e 2020-05-05 rsc 	return t;
397 47d4646e 2020-05-05 rsc }
398 47d4646e 2020-05-05 rsc 
399 47d4646e 2020-05-05 rsc static tree*
400 ff74f7cd 2020-05-05 rsc yyword(int tok, int *ptok, int eqok)
401 47d4646e 2020-05-05 rsc {
402 47d4646e 2020-05-05 rsc 	tree *t;
403 47d4646e 2020-05-05 rsc 
404 47d4646e 2020-05-05 rsc 	// word:	keyword			{lastword=1; $1->type=WORD;}
405 47d4646e 2020-05-05 rsc 	// |	comword
406 47d4646e 2020-05-05 rsc 	// |	word '^' word		{$$=tree2('^', $1, $3);}
407 47d4646e 2020-05-05 rsc 	// comword: '$' word		{$$=tree1('$', $2);}
408 47d4646e 2020-05-05 rsc 	// |	'$' word SUB words ')'	{$$=tree2(SUB, $2, $4);}
409 47d4646e 2020-05-05 rsc 	// |	'"' word		{$$=tree1('"', $2);}
410 47d4646e 2020-05-05 rsc 	// |	COUNT word		{$$=tree1(COUNT, $2);}
411 47d4646e 2020-05-05 rsc 	// |	WORD
412 47d4646e 2020-05-05 rsc 	// |	'`' brace		{$$=tree1('`', $2);}
413 47d4646e 2020-05-05 rsc 	// |	'(' words ')'		{$$=tree1(PAREN, $2);}
414 47d4646e 2020-05-05 rsc 	// |	REDIR brace		{$$=mung1($1, $2); $$->type=PIPEFD;}
415 47d4646e 2020-05-05 rsc 	// keyword: FOR|IN|WHILE|IF|NOT|TWIDDLE|BANG|SUBSHELL|SWITCH|FN
416 47d4646e 2020-05-05 rsc 	//
417 47d4646e 2020-05-05 rsc 	// factored into:
418 47d4646e 2020-05-05 rsc 	//
419 47d4646e 2020-05-05 rsc 	// word: word1
420 47d4646e 2020-05-05 rsc 	// | word '^' word1
421 47d4646e 2020-05-05 rsc 	//
422 47d4646e 2020-05-05 rsc 	// word1: keyword | comword
423 47d4646e 2020-05-05 rsc 
424 47d4646e 2020-05-05 rsc 	t = word1(tok, &tok);
425 ff74f7cd 2020-05-05 rsc 	if(tok == '=' && !eqok)
426 ff74f7cd 2020-05-05 rsc 		goto out;
427 7d6a248f 2020-05-05 rsc 	for(;;) {
428 7d6a248f 2020-05-05 rsc 		if(iswordtok(tok)) {
429 601e07b6 2020-05-05 rsc 			// No free carats around parens.
430 601e07b6 2020-05-05 rsc 			if(t->type == PAREN || tok == '(')
431 601e07b6 2020-05-05 rsc 				syntax(tok);
432 7d6a248f 2020-05-05 rsc 			t = tree2('^', t, word1(tok, &tok));
433 7d6a248f 2020-05-05 rsc 			continue;
434 7d6a248f 2020-05-05 rsc 		}
435 7d6a248f 2020-05-05 rsc 		tok = dropsp(tok);
436 7d6a248f 2020-05-05 rsc 		if(tok == '^') {
437 7d6a248f 2020-05-05 rsc 			t = tree2('^', t, word1(yylex(), &tok));
438 7d6a248f 2020-05-05 rsc 			continue;
439 7d6a248f 2020-05-05 rsc 		}
440 7d6a248f 2020-05-05 rsc 		break;
441 7d6a248f 2020-05-05 rsc 	}
442 ff74f7cd 2020-05-05 rsc out:
443 7d6a248f 2020-05-05 rsc 	*ptok = dropsp(tok);
444 47d4646e 2020-05-05 rsc 	return t;
445 47d4646e 2020-05-05 rsc }
446 47d4646e 2020-05-05 rsc 
447 47d4646e 2020-05-05 rsc static tree*
448 47d4646e 2020-05-05 rsc word1(int tok, int *ptok)
449 47d4646e 2020-05-05 rsc {
450 47d4646e 2020-05-05 rsc 	tree *w, *sub, *t;
451 47d4646e 2020-05-05 rsc 
452 7d6a248f 2020-05-05 rsc 	tok = dropsp(tok);
453 47d4646e 2020-05-05 rsc 	switch(tok) {
454 47d4646e 2020-05-05 rsc 	default:
455 47d4646e 2020-05-05 rsc 		syntax(tok);
456 47d4646e 2020-05-05 rsc 
457 47d4646e 2020-05-05 rsc 	case WORD:
458 47d4646e 2020-05-05 rsc 	case FOR:
459 47d4646e 2020-05-05 rsc 	case IN:
460 47d4646e 2020-05-05 rsc 	case WHILE:
461 47d4646e 2020-05-05 rsc 	case IF:
462 47d4646e 2020-05-05 rsc 	case NOT:
463 47d4646e 2020-05-05 rsc 	case TWIDDLE:
464 47d4646e 2020-05-05 rsc 	case BANG:
465 47d4646e 2020-05-05 rsc 	case SUBSHELL:
466 47d4646e 2020-05-05 rsc 	case SWITCH:
467 47d4646e 2020-05-05 rsc 	case FN:
468 47d4646e 2020-05-05 rsc 		// |	WORD
469 47d4646e 2020-05-05 rsc 		// keyword: FOR|IN|WHILE|IF|NOT|TWIDDLE|BANG|SUBSHELL|SWITCH|FN
470 47d4646e 2020-05-05 rsc 		t = yylval.tree;
471 47d4646e 2020-05-05 rsc 		t->type = WORD;
472 47d4646e 2020-05-05 rsc 		*ptok = yylex();
473 47d4646e 2020-05-05 rsc 		return t;
474 47d4646e 2020-05-05 rsc 
475 ff74f7cd 2020-05-05 rsc 	case '=':
476 ff74f7cd 2020-05-05 rsc 		*ptok = yylex();
477 ff74f7cd 2020-05-05 rsc 		return token("=", WORD);
478 ff74f7cd 2020-05-05 rsc 
479 47d4646e 2020-05-05 rsc 	case '$':
480 47d4646e 2020-05-05 rsc 		// comword: '$' word1		{$$=tree1('$', $2);}
481 47d4646e 2020-05-05 rsc 		// |	'$' word1 SUB words ')'	{$$=tree2(SUB, $2, $4);}
482 47d4646e 2020-05-05 rsc 		w = word1(yylex(), &tok);
483 7d6a248f 2020-05-05 rsc 		if(tok == '(') {
484 47d4646e 2020-05-05 rsc 			sub = words(yylex(), &tok);
485 47d4646e 2020-05-05 rsc 			if(tok != ')')
486 47d4646e 2020-05-05 rsc 				syntax(tok);
487 47d4646e 2020-05-05 rsc 			*ptok = yylex();
488 47d4646e 2020-05-05 rsc 			return tree2(SUB, w, sub);
489 47d4646e 2020-05-05 rsc 		}
490 47d4646e 2020-05-05 rsc 		*ptok = tok;
491 47d4646e 2020-05-05 rsc 		return tree1('$', w);
492 47d4646e 2020-05-05 rsc 
493 47d4646e 2020-05-05 rsc 	case '"':
494 47d4646e 2020-05-05 rsc 		// |	'"' word1		{$$=tree1('"', $2);}
495 47d4646e 2020-05-05 rsc 		return tree1('"', word1(yylex(), ptok));
496 47d4646e 2020-05-05 rsc 
497 47d4646e 2020-05-05 rsc 	case COUNT:
498 47d4646e 2020-05-05 rsc 		// |	COUNT word1		{$$=tree1(COUNT, $2);}
499 47d4646e 2020-05-05 rsc 		return tree1(COUNT, word1(yylex(), ptok));
500 47d4646e 2020-05-05 rsc 
501 47d4646e 2020-05-05 rsc 	case '`':
502 47d4646e 2020-05-05 rsc 		// |	'`' brace		{$$=tree1('`', $2);}
503 47d4646e 2020-05-05 rsc 		t = tree1('`', brace(yylex()));
504 47d4646e 2020-05-05 rsc 		*ptok = yylex();
505 47d4646e 2020-05-05 rsc 		return t;
506 47d4646e 2020-05-05 rsc 
507 47d4646e 2020-05-05 rsc 	case '(':
508 47d4646e 2020-05-05 rsc 		// |	'(' words ')'		{$$=tree1(PAREN, $2);}
509 47d4646e 2020-05-05 rsc 		t = tree1(PAREN, words(yylex(), &tok));
510 47d4646e 2020-05-05 rsc 		if(tok != ')')
511 47d4646e 2020-05-05 rsc 			syntax(tok);
512 47d4646e 2020-05-05 rsc 		*ptok = yylex();
513 47d4646e 2020-05-05 rsc 		return t;
514 47d4646e 2020-05-05 rsc 
515 47d4646e 2020-05-05 rsc 	case REDIRW:
516 47d4646e 2020-05-05 rsc 		// |	REDIRW brace		{$$=mung1($1, $2); $$->type=PIPEFD;}
517 47d4646e 2020-05-05 rsc 		t = yylval.tree;
518 47d4646e 2020-05-05 rsc 		t = mung1(t, brace(yylex()));
519 47d4646e 2020-05-05 rsc 		t->type = PIPEFD;
520 47d4646e 2020-05-05 rsc 		*ptok = yylex();
521 47d4646e 2020-05-05 rsc 		return t;
522 47d4646e 2020-05-05 rsc 	}
523 47d4646e 2020-05-05 rsc }
524 47d4646e 2020-05-05 rsc 
525 47d4646e 2020-05-05 rsc static int
526 47d4646e 2020-05-05 rsc iswordtok(int tok)
527 47d4646e 2020-05-05 rsc {
528 47d4646e 2020-05-05 rsc 	switch(tok) {
529 47d4646e 2020-05-05 rsc 	case FOR:
530 47d4646e 2020-05-05 rsc 	case IN:
531 47d4646e 2020-05-05 rsc 	case WHILE:
532 47d4646e 2020-05-05 rsc 	case IF:
533 47d4646e 2020-05-05 rsc 	case NOT:
534 47d4646e 2020-05-05 rsc 	case TWIDDLE:
535 47d4646e 2020-05-05 rsc 	case BANG:
536 47d4646e 2020-05-05 rsc 	case SUBSHELL:
537 47d4646e 2020-05-05 rsc 	case SWITCH:
538 47d4646e 2020-05-05 rsc 	case FN:
539 47d4646e 2020-05-05 rsc 	case '$':
540 47d4646e 2020-05-05 rsc 	case '"':
541 47d4646e 2020-05-05 rsc 	case COUNT:
542 47d4646e 2020-05-05 rsc 	case WORD:
543 47d4646e 2020-05-05 rsc 	case '`':
544 47d4646e 2020-05-05 rsc 	case '(':
545 47d4646e 2020-05-05 rsc 	case REDIRW:
546 ff74f7cd 2020-05-05 rsc 	case '=':
547 47d4646e 2020-05-05 rsc 		return 1;
548 47d4646e 2020-05-05 rsc 	}
549 47d4646e 2020-05-05 rsc 	return 0;
550 47d4646e 2020-05-05 rsc }