Shared temp file handling code (should have been committed with r617)

git-svn-id: svn+ssh://svn.openpam.org/svn/openpam/trunk@618 185d5e19-27fe-0310-9dcf-9bff6b9f3609

t/t_file.c

@@ -0,0 +1,161 @@
+/*-
+ * Copyright (c) 2012 Dag-Erling Smørgrav
+ * 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
+ *    in this position and unchanged.
+ * 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. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior written
+ *    permission.
+ *
+ * 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.
+ *
+ * $Id$
+ */
+
+#ifdef HAVE_CONFIG_H
+# include "config.h"
+#endif
+
+#include <err.h>
+#include <errno.h>
+#include <fcntl.h>
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "openpam_asprintf.h"
+
+#include "t.h"
+
+static struct t_file *tflist;
+
+/*
+ * Open a temp file.
+ */
+struct t_file *
+t_fopen(const char *filename)
+{
+	struct t_file *tf;
+	int fd;
+
+	if ((tf = calloc(sizeof *tf, 1)) == NULL)
+		err(1, "%s(): calloc()", __func__);
+	if (filename) {
+		if ((tf->name = strdup(filename)) == NULL)
+			err(1, "%s(): strdup()", __func__);
+	} else {
+		asprintf(&tf->name, "%s.%lu.%p.tmp",
+		    t_progname, (unsigned long)getpid(), (void *)tf);
+		if (tf->name == NULL)
+			err(1, "%s(): asprintf()", __func__);
+	}
+	if ((fd = open(tf->name, O_RDWR|O_CREAT|O_TRUNC, 0600)) < 0)
+		err(1, "%s(): %s", __func__, tf->name);
+	if ((tf->file = fdopen(fd, "r+")) == NULL)
+		err(1, "%s(): fdopen()", __func__);
+	if ((tf->next = tflist) != NULL)
+		tf->next->prev = tf;
+	tflist = tf;
+	return (tf);
+}
+
+/*
+ * Write text to the temp file.
+ */
+int
+t_fprintf(struct t_file *tf, const char *fmt, ...)
+{
+	va_list ap;
+	int len;
+
+	va_start(ap, fmt);
+	len = vfprintf(tf->file, fmt, ap);
+	va_end(ap);
+	if (ferror(tf->file))
+		err(1, "%s(): vfprintf()", __func__);
+	return (len);
+}
+
+/*
+ * Rewind the temp file.
+ */
+void
+t_frewind(struct t_file *tf)
+{
+
+	errno = 0;
+	rewind(tf->file);
+	if (errno != 0)
+		err(1, "%s(): rewind()", __func__);
+}
+
+/*
+ * Return non-zero if an error occurred.
+ */
+int
+t_ferror(struct t_file *tf)
+{
+
+	return (ferror(tf->file));
+}
+
+/*
+ * Return non-zero if the end of the file was reached.
+ */
+int
+t_feof(struct t_file *tf)
+{
+
+	return (feof(tf->file));
+}
+
+/*
+ * Close a temp file.
+ */
+void
+t_fclose(struct t_file *tf)
+{
+
+	if (tf == tflist)
+		tflist = tf->next;
+	if (tf->prev)
+		tf->prev->next = tf->next;
+	if (tf->next)
+		tf->next->prev = tf->prev;
+	fclose(tf->file);
+	if (unlink(tf->name) < 0)
+		warn("%s(): unlink()", __func__);
+	free(tf->name);
+	free(tf);
+}
+
+/*
+ * atexit() function to close all remaining files.
+ */
+void
+t_fcloseall(void)
+{
+
+	while (tflist)
+		t_fclose(tflist);
+}