1 files changed, 152 insertions, 0 deletions
diff --git a/lib/isc/stdio.c b/lib/isc/stdio.c
new file mode 100644
index 0000000..12ab678
--- /dev/null
+++ b/lib/isc/stdio.c
@@ -0,0 +1,152 @@
+/*
+ * Copyright (C) Internet Systems Consortium, Inc. ("ISC")
+ *
+ * SPDX-License-Identifier: MPL-2.0
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, you can obtain one at https://mozilla.org/MPL/2.0/.
+ *
+ * See the COPYRIGHT file distributed with this work for additional
+ * information regarding copyright ownership.
+ */
+
+#include <errno.h>
+#include <unistd.h>
+
+#include <isc/stat.h>
+#include <isc/stdio.h>
+#include <isc/util.h>
+
+#include "errno2result.h"
+
+isc_result_t
+isc_stdio_open(const char *filename, const char *mode, FILE **fp) {
+	FILE *f;
+
+	f = fopen(filename, mode);
+	if (f == NULL) {
+		return (isc__errno2result(errno));
+	}
+	*fp = f;
+	return (ISC_R_SUCCESS);
+}
+
+isc_result_t
+isc_stdio_close(FILE *f) {
+	int r;
+
+	r = fclose(f);
+	if (r == 0) {
+		return (ISC_R_SUCCESS);
+	} else {
+		return (isc__errno2result(errno));
+	}
+}
+
+isc_result_t
+isc_stdio_seek(FILE *f, off_t offset, int whence) {
+	int r;
+
+	r = fseeko(f, offset, whence);
+	if (r == 0) {
+		return (ISC_R_SUCCESS);
+	} else {
+		return (isc__errno2result(errno));
+	}
+}
+
+isc_result_t
+isc_stdio_tell(FILE *f, off_t *offsetp) {
+	off_t r;
+
+	REQUIRE(offsetp != NULL);
+
+	r = ftello(f);
+	if (r >= 0) {
+		*offsetp = r;
+		return (ISC_R_SUCCESS);
+	} else {
+		return (isc__errno2result(errno));
+	}
+}
+
+isc_result_t
+isc_stdio_read(void *ptr, size_t size, size_t nmemb, FILE *f, size_t *nret) {
+	isc_result_t result = ISC_R_SUCCESS;
+	size_t r;
+
+	clearerr(f);
+	r = fread(ptr, size, nmemb, f);
+	if (r != nmemb) {
+		if (feof(f)) {
+			result = ISC_R_EOF;
+		} else {
+			result = isc__errno2result(errno);
+		}
+	}
+	if (nret != NULL) {
+		*nret = r;
+	}
+	return (result);
+}
+
+isc_result_t
+isc_stdio_write(const void *ptr, size_t size, size_t nmemb, FILE *f,
+		size_t *nret) {
+	isc_result_t result = ISC_R_SUCCESS;
+	size_t r;
+
+	clearerr(f);
+	r = fwrite(ptr, size, nmemb, f);
+	if (r != nmemb) {
+		result = isc__errno2result(errno);
+	}
+	if (nret != NULL) {
+		*nret = r;
+	}
+	return (result);
+}
+
+isc_result_t
+isc_stdio_flush(FILE *f) {
+	int r;
+
+	r = fflush(f);
+	if (r == 0) {
+		return (ISC_R_SUCCESS);
+	} else {
+		return (isc__errno2result(errno));
+	}
+}
+
+/*
+ * OpenBSD has deprecated ENOTSUP in favor of EOPNOTSUPP.
+ */
+#if defined(EOPNOTSUPP) && !defined(ENOTSUP)
+#define ENOTSUP EOPNOTSUPP
+#endif /* if defined(EOPNOTSUPP) && !defined(ENOTSUP) */
+
+isc_result_t
+isc_stdio_sync(FILE *f) {
+	struct stat buf;
+	int r;
+
+	if (fstat(fileno(f), &buf) != 0) {
+		return (isc__errno2result(errno));
+	}
+
+	/*
+	 * Only call fsync() on regular files.
+	 */
+	if ((buf.st_mode & S_IFMT) != S_IFREG) {
+		return (ISC_R_SUCCESS);
+	}
+
+	r = fsync(fileno(f));
+	if (r == 0) {
+		return (ISC_R_SUCCESS);
+	} else {
+		return (isc__errno2result(errno));
+	}
+}