1 4ee543e5 2005-03-18 devnull #include <u.h>
  2 4ee543e5 2005-03-18 devnull #include <signal.h>
  3 f08fdedc 2003-11-23 devnull #include "rc.h"
  4 f08fdedc 2003-11-23 devnull #include "getflags.h"
  5 f08fdedc 2003-11-23 devnull #include "exec.h"
  6 f08fdedc 2003-11-23 devnull #include "io.h"
  7 f08fdedc 2003-11-23 devnull #include "fns.h"
  8 f08fdedc 2003-11-23 devnull 
  9 f08fdedc 2003-11-23 devnull int havefork = 1;
 10 f08fdedc 2003-11-23 devnull 
 11 f08fdedc 2003-11-23 devnull void
 12 f08fdedc 2003-11-23 devnull Xasync(void)
 13 f08fdedc 2003-11-23 devnull {
 14 f08fdedc 2003-11-23 devnull 	int null = open("/dev/null", 0);
 15 f08fdedc 2003-11-23 devnull 	int pid;
 16 4ee543e5 2005-03-18 devnull 	int tcpgrp, pgrp;
 17 f08fdedc 2003-11-23 devnull 	char npid[10];
 18 4ee543e5 2005-03-18 devnull 
 19 f08fdedc 2003-11-23 devnull 	if(null<0){
 20 f08fdedc 2003-11-23 devnull 		Xerror("Can't open /dev/null\n");
 21 f08fdedc 2003-11-23 devnull 		return;
 22 f08fdedc 2003-11-23 devnull 	}
 23 f08fdedc 2003-11-23 devnull 	switch(pid = rfork(RFFDG|RFPROC|RFNOTEG)){
 24 f08fdedc 2003-11-23 devnull 	case -1:
 25 f08fdedc 2003-11-23 devnull 		close(null);
 26 f08fdedc 2003-11-23 devnull 		Xerror("try again");
 27 f08fdedc 2003-11-23 devnull 		break;
 28 f08fdedc 2003-11-23 devnull 	case 0:
 29 4ee543e5 2005-03-18 devnull 		/*
 30 4ee543e5 2005-03-18 devnull 		 * Should make reads of tty fail, writes succeed.
 31 4ee543e5 2005-03-18 devnull 		 */
 32 4ee543e5 2005-03-18 devnull 		signal(SIGTTIN, SIG_IGN);
 33 4ee543e5 2005-03-18 devnull 		signal(SIGTTOU, SIG_IGN);
 34 4ee543e5 2005-03-18 devnull 
 35 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, null, 0);
 36 f08fdedc 2003-11-23 devnull 		start(runq->code, runq->pc+1, runq->local);
 37 f08fdedc 2003-11-23 devnull 		runq->ret = 0;
 38 f08fdedc 2003-11-23 devnull 		break;
 39 f08fdedc 2003-11-23 devnull 	default:
 40 f08fdedc 2003-11-23 devnull 		close(null);
 41 f08fdedc 2003-11-23 devnull 		runq->pc = runq->code[runq->pc].i;
 42 f08fdedc 2003-11-23 devnull 		inttoascii(npid, pid);
 43 f08fdedc 2003-11-23 devnull 		setvar("apid", newword(npid, (word *)0));
 44 f08fdedc 2003-11-23 devnull 		break;
 45 f08fdedc 2003-11-23 devnull 	}
 46 f08fdedc 2003-11-23 devnull }
 47 f08fdedc 2003-11-23 devnull 
 48 f08fdedc 2003-11-23 devnull void
 49 f08fdedc 2003-11-23 devnull Xpipe(void)
 50 f08fdedc 2003-11-23 devnull {
 51 f08fdedc 2003-11-23 devnull 	struct thread *p = runq;
 52 f08fdedc 2003-11-23 devnull 	int pc = p->pc, forkid;
 53 f08fdedc 2003-11-23 devnull 	int lfd = p->code[pc++].i;
 54 f08fdedc 2003-11-23 devnull 	int rfd = p->code[pc++].i;
 55 f08fdedc 2003-11-23 devnull 	int pfd[2];
 56 f08fdedc 2003-11-23 devnull 	if(pipe(pfd)<0){
 57 f08fdedc 2003-11-23 devnull 		Xerror("can't get pipe");
 58 f08fdedc 2003-11-23 devnull 		return;
 59 f08fdedc 2003-11-23 devnull 	}
 60 f08fdedc 2003-11-23 devnull 	switch(forkid = fork()){
 61 f08fdedc 2003-11-23 devnull 	case -1:
 62 f08fdedc 2003-11-23 devnull 		Xerror("try again");
 63 f08fdedc 2003-11-23 devnull 		break;
 64 f08fdedc 2003-11-23 devnull 	case 0:
 65 f08fdedc 2003-11-23 devnull 		start(p->code, pc+2, runq->local);
 66 f08fdedc 2003-11-23 devnull 		runq->ret = 0;
 67 f08fdedc 2003-11-23 devnull 		close(pfd[PRD]);
 68 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, pfd[PWR], lfd);
 69 f08fdedc 2003-11-23 devnull 		break;
 70 f08fdedc 2003-11-23 devnull 	default:
 71 f08fdedc 2003-11-23 devnull 		start(p->code, p->code[pc].i, runq->local);
 72 f08fdedc 2003-11-23 devnull 		close(pfd[PWR]);
 73 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, pfd[PRD], rfd);
 74 f08fdedc 2003-11-23 devnull 		p->pc = p->code[pc+1].i;
 75 f08fdedc 2003-11-23 devnull 		p->pid = forkid;
 76 f08fdedc 2003-11-23 devnull 		break;
 77 f08fdedc 2003-11-23 devnull 	}
 78 f08fdedc 2003-11-23 devnull }
 79 f08fdedc 2003-11-23 devnull 
 80 f08fdedc 2003-11-23 devnull /*
 81 f08fdedc 2003-11-23 devnull  * Who should wait for the exit from the fork?
 82 f08fdedc 2003-11-23 devnull  */
 83 f08fdedc 2003-11-23 devnull void
 84 f08fdedc 2003-11-23 devnull Xbackq(void)
 85 f08fdedc 2003-11-23 devnull {
 86 f08fdedc 2003-11-23 devnull 	char wd[8193];
 87 f08fdedc 2003-11-23 devnull 	int c;
 88 f08fdedc 2003-11-23 devnull 	char *s, *ewd=&wd[8192], *stop;
 89 f08fdedc 2003-11-23 devnull 	struct io *f;
 90 f08fdedc 2003-11-23 devnull 	var *ifs = vlook("ifs");
 91 f08fdedc 2003-11-23 devnull 	word *v, *nextv;
 92 f08fdedc 2003-11-23 devnull 	int pfd[2];
 93 f08fdedc 2003-11-23 devnull 	int pid;
 94 f08fdedc 2003-11-23 devnull 	stop = ifs->val?ifs->val->word:"";
 95 f08fdedc 2003-11-23 devnull 	if(pipe(pfd)<0){
 96 f08fdedc 2003-11-23 devnull 		Xerror("can't make pipe");
 97 f08fdedc 2003-11-23 devnull 		return;
 98 f08fdedc 2003-11-23 devnull 	}
 99 f08fdedc 2003-11-23 devnull 	switch(pid = fork()){
100 f08fdedc 2003-11-23 devnull 	case -1:
101 f08fdedc 2003-11-23 devnull 		Xerror("try again");
102 f08fdedc 2003-11-23 devnull 		close(pfd[PRD]);
103 f08fdedc 2003-11-23 devnull 		close(pfd[PWR]);
104 f08fdedc 2003-11-23 devnull 		return;
105 f08fdedc 2003-11-23 devnull 	case 0:
106 f08fdedc 2003-11-23 devnull 		close(pfd[PRD]);
107 f08fdedc 2003-11-23 devnull 		start(runq->code, runq->pc+1, runq->local);
108 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, pfd[PWR], 1);
109 f08fdedc 2003-11-23 devnull 		return;
110 f08fdedc 2003-11-23 devnull 	default:
111 f08fdedc 2003-11-23 devnull 		close(pfd[PWR]);
112 f08fdedc 2003-11-23 devnull 		f = openfd(pfd[PRD]);
113 f08fdedc 2003-11-23 devnull 		s = wd;
114 f08fdedc 2003-11-23 devnull 		v = 0;
115 f08fdedc 2003-11-23 devnull 		while((c = rchr(f))!=EOF){
116 f08fdedc 2003-11-23 devnull 			if(strchr(stop, c) || s==ewd){
117 f08fdedc 2003-11-23 devnull 				if(s!=wd){
118 f08fdedc 2003-11-23 devnull 					*s='\0';
119 f08fdedc 2003-11-23 devnull 					v = newword(wd, v);
120 f08fdedc 2003-11-23 devnull 					s = wd;
121 f08fdedc 2003-11-23 devnull 				}
122 f08fdedc 2003-11-23 devnull 			}
123 f08fdedc 2003-11-23 devnull 			else *s++=c;
124 f08fdedc 2003-11-23 devnull 		}
125 f08fdedc 2003-11-23 devnull 		if(s!=wd){
126 f08fdedc 2003-11-23 devnull 			*s='\0';
127 f08fdedc 2003-11-23 devnull 			v = newword(wd, v);
128 f08fdedc 2003-11-23 devnull 		}
129 f08fdedc 2003-11-23 devnull 		closeio(f);
130 f08fdedc 2003-11-23 devnull 		Waitfor(pid, 0);
131 f08fdedc 2003-11-23 devnull 		/* v points to reversed arglist -- reverse it onto argv */
132 f08fdedc 2003-11-23 devnull 		while(v){
133 f08fdedc 2003-11-23 devnull 			nextv = v->next;
134 f08fdedc 2003-11-23 devnull 			v->next = runq->argv->words;
135 f08fdedc 2003-11-23 devnull 			runq->argv->words = v;
136 f08fdedc 2003-11-23 devnull 			v = nextv;
137 f08fdedc 2003-11-23 devnull 		}
138 f08fdedc 2003-11-23 devnull 		runq->pc = runq->code[runq->pc].i;
139 f08fdedc 2003-11-23 devnull 		return;
140 f08fdedc 2003-11-23 devnull 	}
141 f08fdedc 2003-11-23 devnull }
142 f08fdedc 2003-11-23 devnull 
143 f08fdedc 2003-11-23 devnull void
144 f08fdedc 2003-11-23 devnull Xpipefd(void)
145 f08fdedc 2003-11-23 devnull {
146 f08fdedc 2003-11-23 devnull 	struct thread *p = runq;
147 f08fdedc 2003-11-23 devnull 	int pc = p->pc;
148 f08fdedc 2003-11-23 devnull 	char name[40];
149 f08fdedc 2003-11-23 devnull 	int pfd[2];
150 f08fdedc 2003-11-23 devnull 	int sidefd, mainfd;
151 f08fdedc 2003-11-23 devnull 	if(pipe(pfd)<0){
152 f08fdedc 2003-11-23 devnull 		Xerror("can't get pipe");
153 f08fdedc 2003-11-23 devnull 		return;
154 f08fdedc 2003-11-23 devnull 	}
155 f08fdedc 2003-11-23 devnull 	if(p->code[pc].i==READ){
156 f08fdedc 2003-11-23 devnull 		sidefd = pfd[PWR];
157 f08fdedc 2003-11-23 devnull 		mainfd = pfd[PRD];
158 f08fdedc 2003-11-23 devnull 	}
159 f08fdedc 2003-11-23 devnull 	else{
160 f08fdedc 2003-11-23 devnull 		sidefd = pfd[PRD];
161 f08fdedc 2003-11-23 devnull 		mainfd = pfd[PWR];
162 f08fdedc 2003-11-23 devnull 	}
163 f08fdedc 2003-11-23 devnull 	switch(fork()){
164 f08fdedc 2003-11-23 devnull 	case -1:
165 f08fdedc 2003-11-23 devnull 		Xerror("try again");
166 f08fdedc 2003-11-23 devnull 		break;
167 f08fdedc 2003-11-23 devnull 	case 0:
168 f08fdedc 2003-11-23 devnull 		start(p->code, pc+2, runq->local);
169 f08fdedc 2003-11-23 devnull 		close(mainfd);
170 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, sidefd, p->code[pc].i==READ?1:0);
171 f08fdedc 2003-11-23 devnull 		runq->ret = 0;
172 f08fdedc 2003-11-23 devnull 		break;
173 f08fdedc 2003-11-23 devnull 	default:
174 f08fdedc 2003-11-23 devnull 		close(sidefd);
175 f08fdedc 2003-11-23 devnull 		pushredir(ROPEN, mainfd, mainfd);	/* isn't this a noop? */
176 f08fdedc 2003-11-23 devnull 		strcpy(name, Fdprefix);
177 f08fdedc 2003-11-23 devnull 		inttoascii(name+strlen(name), mainfd);
178 f08fdedc 2003-11-23 devnull 		pushword(name);
179 f08fdedc 2003-11-23 devnull 		p->pc = p->code[pc+1].i;
180 f08fdedc 2003-11-23 devnull 		break;
181 f08fdedc 2003-11-23 devnull 	}
182 f08fdedc 2003-11-23 devnull }
183 f08fdedc 2003-11-23 devnull 
184 f08fdedc 2003-11-23 devnull void
185 f08fdedc 2003-11-23 devnull Xsubshell(void)
186 f08fdedc 2003-11-23 devnull {
187 f08fdedc 2003-11-23 devnull 	int pid;
188 f08fdedc 2003-11-23 devnull 	switch(pid = fork()){
189 f08fdedc 2003-11-23 devnull 	case -1:
190 f08fdedc 2003-11-23 devnull 		Xerror("try again");
191 f08fdedc 2003-11-23 devnull 		break;
192 f08fdedc 2003-11-23 devnull 	case 0:
193 f08fdedc 2003-11-23 devnull 		start(runq->code, runq->pc+1, runq->local);
194 f08fdedc 2003-11-23 devnull 		runq->ret = 0;
195 f08fdedc 2003-11-23 devnull 		break;
196 f08fdedc 2003-11-23 devnull 	default:
197 f08fdedc 2003-11-23 devnull 		Waitfor(pid, 1);
198 f08fdedc 2003-11-23 devnull 		runq->pc = runq->code[runq->pc].i;
199 f08fdedc 2003-11-23 devnull 		break;
200 f08fdedc 2003-11-23 devnull 	}
201 f08fdedc 2003-11-23 devnull }
202 f08fdedc 2003-11-23 devnull 
203 f08fdedc 2003-11-23 devnull int
204 f08fdedc 2003-11-23 devnull execforkexec(void)
205 f08fdedc 2003-11-23 devnull {
206 f08fdedc 2003-11-23 devnull 	int pid;
207 f08fdedc 2003-11-23 devnull 	int n;
208 f08fdedc 2003-11-23 devnull 	char buf[ERRMAX];
209 f08fdedc 2003-11-23 devnull 
210 f08fdedc 2003-11-23 devnull 	switch(pid = fork()){
211 f08fdedc 2003-11-23 devnull 	case -1:
212 f08fdedc 2003-11-23 devnull 		return -1;
213 f08fdedc 2003-11-23 devnull 	case 0:
214 f08fdedc 2003-11-23 devnull 		pushword("exec");
215 f08fdedc 2003-11-23 devnull 		execexec();
216 f08fdedc 2003-11-23 devnull 		strcpy(buf, "can't exec: ");
217 f08fdedc 2003-11-23 devnull 		n = strlen(buf);
218 f08fdedc 2003-11-23 devnull 		errstr(buf+n, ERRMAX-n);
219 f08fdedc 2003-11-23 devnull 		Exit(buf);
220 f08fdedc 2003-11-23 devnull 	}
221 f08fdedc 2003-11-23 devnull 	return pid;
222 f08fdedc 2003-11-23 devnull }