Initial revision

src/cmd/sam/shell.c

@@ -0,0 +1,152 @@
+#include "sam.h"
+#include "parse.h"
+
+extern	jmp_buf	mainloop;
+
+char	errfile[64];
+String	plan9cmd;	/* null terminated */
+Buffer	plan9buf;
+void	checkerrs(void);
+
+int
+plan9(File *f, int type, String *s, int nest)
+{
+	long l;
+	int m;
+	int pid, fd;
+	int retcode;
+	int pipe1[2], pipe2[2];
+
+	if(s->s[0]==0 && plan9cmd.s[0]==0)
+		error(Enocmd);
+	else if(s->s[0])
+		Strduplstr(&plan9cmd, s);
+	if(downloaded){
+		samerr(errfile);
+		remove(errfile);
+	}
+	if(type!='!' && pipe(pipe1)==-1)
+		error(Epipe);
+	if(type=='|')
+		snarf(f, addr.r.p1, addr.r.p2, &plan9buf, 1);
+	if((pid=fork()) == 0){
+		if(downloaded){	/* also put nasty fd's into errfile */
+			fd = create(errfile, 1, 0666L);
+			if(fd < 0)
+				fd = create("/dev/null", 1, 0666L);
+			dup(fd, 2);
+			close(fd);
+			/* 2 now points at err file */
+			if(type == '>')
+				dup(2, 1);
+			else if(type=='!'){
+				dup(2, 1);
+				fd = open("/dev/null", 0);
+				dup(fd, 0);
+				close(fd);
+			}
+		}
+		if(type != '!') {
+			if(type=='<' || type=='|')
+				dup(pipe1[1], 1);
+			else if(type == '>')
+				dup(pipe1[0], 0);
+			close(pipe1[0]);
+			close(pipe1[1]);
+		}
+		if(type == '|'){
+			if(pipe(pipe2) == -1)
+				exits("pipe");
+			if((pid = fork())==0){
+				/*
+				 * It's ok if we get SIGPIPE here
+				 */
+				close(pipe2[0]);
+				io = pipe2[1];
+				if(retcode=!setjmp(mainloop)){	/* assignment = */
+					char *c;
+					for(l = 0; l<plan9buf.nc; l+=m){
+						m = plan9buf.nc-l;
+						if(m>BLOCKSIZE-1)
+							m = BLOCKSIZE-1;
+						bufread(&plan9buf, l, genbuf, m);
+						genbuf[m] = 0;
+						c = Strtoc(tmprstr(genbuf, m+1));
+						Write(pipe2[1], c, strlen(c));
+						free(c);
+					}
+				}
+				exits(retcode? "error" : 0);
+			}
+			if(pid==-1){
+				fprint(2, "Can't fork?!\n");
+				exits("fork");
+			}
+			dup(pipe2[0], 0);
+			close(pipe2[0]);
+			close(pipe2[1]);
+		}
+		if(type=='<'){
+			close(0);	/* so it won't read from terminal */
+			open("/dev/null", 0);
+		}
+		execl(SHPATH, SH, "-c", Strtoc(&plan9cmd), (char *)0);
+		exits("exec");
+	}
+	if(pid == -1)
+		error(Efork);
+	if(type=='<' || type=='|'){
+		int nulls;
+		if(downloaded && addr.r.p1 != addr.r.p2)
+			outTl(Hsnarflen, addr.r.p2-addr.r.p1);
+		snarf(f, addr.r.p1, addr.r.p2, &snarfbuf, 0);
+		logdelete(f, addr.r.p1, addr.r.p2);
+		close(pipe1[1]);
+		io = pipe1[0];
+		f->tdot.p1 = -1;
+		f->ndot.r.p2 = addr.r.p2+readio(f, &nulls, 0, FALSE);
+		f->ndot.r.p1 = addr.r.p2;
+		closeio((Posn)-1);
+	}else if(type=='>'){
+		close(pipe1[0]);
+		io = pipe1[1];
+		bpipeok = 1;
+		writeio(f);
+		bpipeok = 0;
+		closeio((Posn)-1);
+	}
+	retcode = waitfor(pid);
+	if(type=='|' || type=='<')
+		if(retcode!=0)
+			warn(Wbadstatus);
+	if(downloaded)
+		checkerrs();
+	if(!nest)
+		dprint("!\n");
+	return retcode;
+}
+
+void
+checkerrs(void)
+{
+	char buf[256];
+	int f, n, nl;
+	char *p;
+	long l;
+
+	if(statfile(errfile, 0, 0, 0, &l, 0) > 0 && l != 0){
+		if((f=open((char *)errfile, 0)) != -1){
+			if((n=read(f, buf, sizeof buf-1)) > 0){
+				for(nl=0,p=buf; nl<3 && p<&buf[n]; p++)
+					if(*p=='\n')
+						nl++;
+				*p = 0;
+				dprint("%s", buf);
+				if(p-buf < l-1)
+					dprint("(sam: more in %s)\n", errfile);
+			}
+			close(f);
+		}
+	}else
+		remove((char *)errfile);
+}