Initial Spring 2016 commit.

userland/lib/libc/unix/err.c

@@ -0,0 +1,191 @@
+/*
+ * Copyright (c) 2000, 2001, 2002, 2003, 2004, 2005, 2008, 2009
+ *	The President and Fellows of Harvard College.
+ *
+ * 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.
+ * 3. Neither the name of the University nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE UNIVERSITY 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 UNIVERSITY 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.
+ */
+
+#include <stdio.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <err.h>
+#include <errno.h>
+
+/*
+ * 4.4BSD error printing functions.
+ */
+
+/*
+ * This is initialized by crt0, though it actually lives in errno.c
+ */
+extern char **__argv;
+
+/*
+ * Routine to print error message text to stderr.
+ */
+static
+void
+__senderr(void *junk, const char *data, size_t len)
+{
+	(void)junk;  /* not needed or used */
+
+	write(STDERR_FILENO, data, len);
+}
+
+/*
+ * Shortcut to call __senderr on a null-terminated string.
+ * (__senderr is set up to be called by __vprintf.)
+ */
+static
+void
+__senderrstr(const char *str)
+{
+	__senderr(NULL, str, strlen(str));
+}
+
+/*
+ * Common routine for all the *err* and *warn* functions.
+ */
+static
+void
+__printerr(int use_errno, const char *fmt, va_list ap)
+{
+	const char *errmsg;
+	const char *prog;
+
+	/*
+	 * Get the error message for the current errno.
+	 * Do this early, before doing anything that might change the
+	 * value in errno.
+	 */
+	errmsg = strerror(errno);
+
+	/*
+	 * Look up the program name.
+	 * Strictly speaking we should pull off the rightmost
+	 * path component of argv[0] and use that as the program
+	 * name (this is how BSD err* prints) but it doesn't make
+	 * much difference.
+	 */
+	if (__argv!=NULL && __argv[0]!=NULL) {
+		prog = __argv[0];
+	}
+	else {
+		prog = "(program name unknown)";
+	}
+
+	/* print the program name */
+	__senderrstr(prog);
+	__senderrstr(": ");
+
+	/* process the printf format and args */
+	__vprintf(__senderr, NULL, fmt, ap);
+
+	/* if we're using errno, print the error string from above. */
+	if (use_errno) {
+		__senderrstr(": ");
+		__senderrstr(errmsg);
+	}
+
+	/* and always add a newline. */
+	__senderrstr("\n");
+}
+
+/*
+ * The va_list versions of the warn/err functions.
+ */
+
+/* warn/vwarn: use errno, don't exit */
+void
+vwarn(const char *fmt, va_list ap)
+{
+	__printerr(1, fmt, ap);
+}
+
+/* warnx/vwarnx: don't use errno, don't exit */
+void
+vwarnx(const char *fmt, va_list ap)
+{
+	__printerr(0, fmt, ap);
+}
+
+/* err/verr: use errno, then exit */
+void
+verr(int exitcode, const char *fmt, va_list ap)
+{
+	__printerr(1, fmt, ap);
+	exit(exitcode);
+}
+
+/* errx/verrx: don't use errno, but do then exit */
+void
+verrx(int exitcode, const char *fmt, va_list ap)
+{
+	__printerr(0, fmt, ap);
+	exit(exitcode);
+}
+
+/*
+ * The non-va_list versions of the warn/err functions.
+ * Just hand off to the va_list versions.
+ */
+
+void
+warn(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vwarn(fmt, ap);
+	va_end(ap);
+}
+
+void
+warnx(const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	vwarnx(fmt, ap);
+	va_end(ap);
+}
+
+void
+err(int exitcode, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	verr(exitcode, fmt, ap);
+	va_end(ap);
+}
+
+void
+errx(int exitcode, const char *fmt, ...)
+{
+	va_list ap;
+	va_start(ap, fmt);
+	verrx(exitcode, fmt, ap);
+	va_end(ap);
+}