dj(1): more refactor (get rid of ep pun)

src/dj.c

@@ -156,6 +156,9 @@ Io_fdseek(struct Io *io){
 			|| (!fdisstd(io->fd) && lseek(io->fd, io->seek, SEEK_SET) != -1))
 		return;
 
+	if(io->fl == write_flags)
+		memset(io->buf, '\0', io->bs);
+
 	if(io->fl == write_flags){
 		memset(io->buf, '\0', io->bs);
 		/* We're going to cheat and use bufuse as the retval for write(2),
@@ -273,7 +276,7 @@ usage(void){
 int main(int argc, char *argv[]){
 	int align; /* low 8b used, negative if no alignment is being done */
 	int count; /* 0 if dj(1) runs until no more reads are possible */
-	struct Io ep[2]; /* "engineered pipe"; also "extended play", for the DJ */
+	struct Io io[2];
 	char *fmt_output; /* fmt_asv (default) or fmt_human (-H) */
 	char noerror; /* 0=exits (default) 1=retries on partial reads or writes */
 	int c;
@@ -284,10 +287,10 @@ int main(int argc, char *argv[]){
 	count = 0;
 	fmt_output = fmt_asv;
 	noerror = 0;
-	ep[0].fl = read_flags;
+	io[0].fl = read_flags;
-	Io_setdefaults(&ep[0]);
+	Io_setdefaults(&io[0]);
-	ep[1].fl = write_flags;
+	io[1].fl = write_flags;
-	Io_setdefaults(&ep[1]);
+	Io_setdefaults(&io[1]);
 
 	if(argc > 0){
 		program_name = argv[0];
@@ -296,12 +299,12 @@ int main(int argc, char *argv[]){
 			case 'i': case 'o':
 				i = (c == 'o');
 				if(optarg[0] == '-' && optarg[1] == '\0'){ /* optarg == "-" */
-					ep[i].fd = (i == 0) ? STDIN_FILENO : STDOUT_FILENO;
+					io[i].fd = (i == 0) ? STDIN_FILENO : STDOUT_FILENO;
-					ep[i].fn = (i == 0) ? stdin_name   : stdout_name;
+					io[i].fn = (i == 0) ? stdin_name   : stdout_name;
 					break;
-				}else if(Io_fdopen(&ep[i], optarg) != -1)
+				}else if(Io_fdopen(&io[i], optarg) != -1)
 					break;
-				terminate(ep);
+				terminate(io);
 				return oserr(optarg);
 			case 'A': align = '\0'; break;
 			case 'n': noerror = 1; break;
@@ -317,82 +320,82 @@ int main(int argc, char *argv[]){
 					break;
 				i = isupper(c);
 				c = tolower(c);
-				if((c == 'b' && (ep[i].bs = parse(optarg)) > 0)
+				if((c == 'b' && (io[i].bs = parse(optarg)) > 0)
-						|| (c == 's' && (ep[i].seek = parse(optarg)) >= 0))
+						|| (c == 's' && (io[i].seek = parse(optarg)) >= 0))
 					break;
 				/* FALLTHROUGH */
 			default:
-				terminate(ep);
+				terminate(io);
 				return usage();
 			}
 	}
 
 	if(argc > optind){
-		terminate(ep);
+		terminate(io);
 		return usage();
 	}
 
-	for(i = 0; i <= 1; ++i){
+	for(i = 0; i < 2; ++i){
-		if(Io_bufalloc(&ep[i]) == NULL){
+		if(Io_bufalloc(&io[i]) == NULL){
 			fprintf(stderr, "%s: Failed to allocate %d bytes\n",
-				program_name, ep[i].bs);
+				program_name, io[i].bs);
-			terminate(ep);
+			terminate(io);
 			return EX_OSERR;
-		}else if(ep[i].seek > 0)
+		}else if(io[i].seek > 0)
-			Io_fdseek(&ep[i]);
+			Io_fdseek(&io[i]);
-			if(ep[i].seek > 0){
+			if(io[i].seek > 0){
-				terminate(ep);
+				terminate(io);
-				return oserr(ep[i].fn);
+				return oserr(io[i].fn);
 			}
 	}
 
 	do{	/* read */
-		Io_read(&ep[0]);
+		Io_read(&io[0]);
-		if(!noerror && ep[0].bufuse == 0)
+		if(!noerror && io[0].bufuse == 0)
-			Io_read(&ep[0]); /* second chance */
+			Io_read(&io[0]); /* second chance */
-		if(ep[0].bufuse == 0) /* that's all she wrote */
+		if(io[0].bufuse == 0) /* that's all she wrote */
 			break;
-		else if(ep[0].bufuse < ep[0].bs){
+		else if(io[0].bufuse < io[0].bs){
-			++ep[0].prec;
+			++io[0].prec;
 			fprintf(stderr, "%s: Partial read:\n\t", program_name);
-			output(ep, fmt_output);
+			output(io, fmt_output);
 			if(!noerror)
 				count = 1;
 			if(align >= 0)
-				Io_bufrpad(&ep[0], align);
+				Io_bufrpad(&io[0], align);
 		}else
-			++ep[0].rec;
+			++io[0].rec;
 
 		/* write */
-		do{	if(ep[1].bs > ep[0].bs){ /* io[1].bs > io[0].bs */
+		do{	if(io[1].bs > io[0].bs){ /* io[1].bs > io[0].bs */
-				Io_bufxapp(&ep[1], &ep[0]);
+				Io_bufxapp(&io[1], &io[0]);
-				if(ep[0].bs + ep[1].bufuse <= ep[1].bs && count != 1)
+				if(io[0].bs + io[1].bufuse <= io[1].bs && count != 1)
 					continue; /* we could write more */
 			}else
-				Io_bufxfer(&ep[1], &ep[0], MIN(ep[0].bufuse, ep[1].bs));
+				Io_bufxfer(&io[1], &io[0], MIN(io[0].bufuse, io[1].bs));
 
-			c = ep[1].bufuse;
+			c = io[1].bufuse;
-			Io_write(&ep[1]);
+			Io_write(&io[1]);
-			if(!noerror && ep[1].bufuse == c)
+			if(!noerror && io[1].bufuse == c)
-				Io_write(&ep[1]); /* second chance */
+				Io_write(&io[1]); /* second chance */
-			if(c == ep[1].bufuse){ /* no more love */
+			if(c == io[1].bufuse){ /* no more love */
 				count = 1;
 				break;
-			}else if(c > ep[1].bufuse && ep[1].bufuse > 0){
+			}else if(c > io[1].bufuse && io[1].bufuse > 0){
-				ep[1].prec += 1;
+				io[1].prec += 1;
 				fprintf(stderr, "%s: Partial write:\n\t", program_name);
-				output(ep, fmt_output);
+				output(io, fmt_output);
 				if(!noerror)
 					count = 1;
-			}else if(ep[1].bufuse == 0 && c < ep[1].bs)
+			}else if(io[1].bufuse == 0 && c < io[1].bs)
-				++ep[1].prec;
+				++io[1].prec;
 			else
-				++ep[1].rec;
+				++io[1].rec;
-		}while(ep[0].bufuse > 0);
+		}while(io[0].bufuse > 0);
 	}while(count == 0 || --count > 0);
 
-	output(ep, fmt_output);
+	output(io, fmt_output);
-	terminate(ep);
+	terminate(io);
 
 	return EX_OK;
 }