summaryrefslogtreecommitdiff
diff options
context:
space:
mode:
authorVito Caputo <vcaputo@pengaru.com>2020-09-22 18:16:38 -0700
committerVito Caputo <vcaputo@pengaru.com>2020-09-22 18:16:38 -0700
commit2944f70ee33de24b023ad1edb04246e4b71eef17 (patch)
treef9841815814e8bc75dbd22290542a7533f520aff
*: initial commit
wye is an input-oriented tee variant The name is derived from the plumbing name for a directional tee, or "Y" intersection.
-rw-r--r--Makefile.am1
-rw-r--r--README12
-rwxr-xr-xbootstrap3
-rw-r--r--configure.ac16
-rw-r--r--src/Makefile.am2
-rw-r--r--src/wye.c93
6 files changed, 127 insertions, 0 deletions
diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..af437a6
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1 @@
+SUBDIRS = src
diff --git a/README b/README
new file mode 100644
index 0000000..e57b6c3
--- /dev/null
+++ b/README
@@ -0,0 +1,12 @@
+`wye` is an input variant of the `tee` utility
+
+Usage is like `tee`: wye [FILE]...
+
+wye always consumes from its stdin, the optional files specified are
+read-multiplexed as alternative inputs to stdin. All reads are
+performed using PIPE_BUF sized buffers which are the atomic units for
+unix pipes, any read data is immediately written to stdout.
+
+Someone should try get this command added upstream in GNU Coreutils
+upstream, and give me credit for the name. This implementation is a
+quick and dirty hack and not particularly robust.
diff --git a/bootstrap b/bootstrap
new file mode 100755
index 0000000..c5a7472
--- /dev/null
+++ b/bootstrap
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+autoreconf --install
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..8cdfc3e
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,16 @@
+AC_INIT([wye], [1.0], [vcaputo@pengaru.com])
+AM_INIT_AUTOMAKE([-Wall -Werror foreign])
+AC_PROG_CC
+AM_PROG_CC_C_O
+AM_PROG_AR
+AC_PROG_RANLIB
+AM_SILENT_RULES([yes])
+
+CFLAGS="$CFLAGS -Wall"
+
+AC_CONFIG_FILES([
+ Makefile
+ src/Makefile
+])
+
+AC_OUTPUT
diff --git a/src/Makefile.am b/src/Makefile.am
new file mode 100644
index 0000000..8490c6e
--- /dev/null
+++ b/src/Makefile.am
@@ -0,0 +1,2 @@
+bin_PROGRAMS = wye
+wye_SOURCES = wye.c
diff --git a/src/wye.c b/src/wye.c
new file mode 100644
index 0000000..17cbc3b
--- /dev/null
+++ b/src/wye.c
@@ -0,0 +1,93 @@
+/*
+ * Copyright (C) 2020 - Vito Caputo - <vcaputo@pengaru.com>
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 3 as published
+ * by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <assert.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <limits.h>
+#include <poll.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <unistd.h>
+
+int main(int argc, char *argv[])
+{
+ int n = argc;
+ struct pollfd *pfds;
+
+ assert(argc >= 1);
+
+ pfds = calloc(n, sizeof(*pfds));
+ if (!pfds) {
+ fprintf(stderr, "Unable to allocate struct pollfd array: %s\n",
+ strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ for (int i = 0; i < n; i++) {
+ if (i > 0) {
+ const char *path = argv[i];
+
+ pfds[i].fd = open(path, O_RDONLY);
+ if (pfds[i].fd == -1) {
+ fprintf(stderr, "Unable to open \"%s\": %s\n",
+ path, strerror(errno));
+ return EXIT_FAILURE;
+ }
+ }
+ pfds[i].events = POLLIN;
+ }
+
+ while (poll(pfds, n, -1) > 0) {
+ for (int i = 0; i < n; i++) {
+ char buf[PIPE_BUF];
+ ssize_t rr, rw;
+
+ if (pfds[i].revents & POLLHUP) {
+ fprintf(stderr, "fd %i hangup, quitting\n",
+ pfds[i].fd);
+ return EXIT_SUCCESS;
+ }
+
+ if (!(pfds[i].revents & POLLIN))
+ continue;
+
+ rr = read(pfds[i].fd, buf, sizeof(buf));
+ if (rr < 0) {
+ fprintf(stderr, "Error reading fd %i: %s\n",
+ pfds[i].fd, strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ rw = write(1, buf, rr);
+ if (rw < 0) {
+ fprintf(stderr, "Error writing: %s\n",
+ strerror(errno));
+ return EXIT_FAILURE;
+ }
+
+ if (rw != rr) {
+ fprintf(stderr, "Short write\n");
+ return EXIT_FAILURE;
+ }
+ }
+ }
+
+ return EXIT_FAILURE;
+}
© 2021 All Rights Reserved