1 files changed, 115 insertions, 0 deletions
diff --git a/lib/libstdbuf/stdbuf.c b/lib/libstdbuf/stdbuf.c
new file mode 100644
index 0000000..1b5d39a
--- /dev/null
+++ b/lib/libstdbuf/stdbuf.c
@@ -0,0 +1,115 @@
+/*-
+ * Copyright (c) 2012 Jeremie Le Hen <jlh@FreeBSD.org>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ *
+ * $FreeBSD$
+ */
+
+#include <err.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+static const char *
+stream_name(FILE *s)
+{
+
+	if (s == stdin)
+		return "stdin";
+	if (s == stdout)
+		return "stdout";
+	if (s == stderr)
+		return "stderr";
+	/* This should not happen. */
+	abort();
+}
+
+static void
+change_buf(FILE *s, const char *bufmode)
+{
+	char *unit;
+	size_t bufsize;
+	int mode;
+
+	bufsize = 0;
+	if (bufmode[0] == '0' && bufmode[1] == '\0')
+		mode = _IONBF;
+	else if (bufmode[0] == 'L' && bufmode[1] == '\0')
+		mode = _IOLBF;
+	else if (bufmode[0] == 'B' && bufmode[1] == '\0') {
+		mode = _IOFBF;
+		bufsize = 0;
+	} else {
+		/*
+		 * This library being preloaded, depending on libutil
+		 * would lead to excessive namespace pollution.
+		 * Thus we do not use expand_number().
+		 */
+		errno = 0;
+		bufsize = strtol(bufmode, &unit, 0);
+		if (errno == EINVAL || errno == ERANGE || unit == bufmode)
+			warn("Wrong buffer mode '%s' for %s", bufmode,
+			    stream_name(s));
+		switch (*unit) {
+		case 'G':
+			bufsize *= 1024 * 1024 * 1024;
+			break;
+		case 'M':
+			bufsize *= 1024 * 1024;
+			break;
+		case 'k':
+			bufsize *= 1024;
+			break;
+		case '\0':
+			break;
+		default:
+			warnx("Unknown suffix '%c' for %s", *unit,
+			    stream_name(s));
+			return;
+		}
+		mode = _IOFBF;
+	}
+	if (setvbuf(s, NULL, mode, bufsize) != 0)
+		warn("Cannot set buffer mode '%s' for %s", bufmode,
+		    stream_name(s));
+}
+
+__attribute__ ((constructor)) static void
+stdbuf(void)
+{
+	char *i_mode, *o_mode, *e_mode;
+
+	i_mode = getenv("_STDBUF_I");
+	o_mode = getenv("_STDBUF_O");
+	e_mode = getenv("_STDBUF_E");
+
+	if (e_mode != NULL)
+		change_buf(stderr, e_mode);
+	if (i_mode != NULL)
+		change_buf(stdin, i_mode);
+	if (o_mode != NULL)
+		change_buf(stdout, o_mode);
+}