1 files changed, 199 insertions, 0 deletions
diff --git a/src/contrib/files.c b/src/contrib/files.c
new file mode 100644
index 0000000..7f24426
--- /dev/null
+++ b/src/contrib/files.c
@@ -0,0 +1,199 @@
+/*  Copyright (C) 2020 CZ.NIC, z.s.p.o. <knot-dns@labs.nic.cz>
+
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    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 <https://www.gnu.org/licenses/>.
+ */
+
+#include <assert.h>
+#include <dirent.h>
+#include <fcntl.h>
+#include <ftw.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/stat.h>
+#include <unistd.h>
+
+#include "contrib/files.h"
+#include "contrib/string.h"
+#include "libknot/errcode.h"
+
+#if defined(MAXBSIZE)
+  #define BUFSIZE MAXBSIZE
+#else
+  #define BUFSIZE (64 * 1024)
+#endif
+
+static int remove_file(const char *path, const struct stat *stat, int type, struct FTW *ftw)
+{
+	(void)stat;
+	(void)ftw;
+	if (type == FTW_DP) {
+		return rmdir(path);
+	} else {
+		return unlink(path);
+	}
+}
+
+bool remove_path(const char *path)
+{
+	return (0 == nftw(path, remove_file, 1, FTW_DEPTH | FTW_PHYS));
+}
+
+int make_dir(const char *path, mode_t mode, bool ignore_existing)
+{
+	if (mkdir(path, mode) == 0) {
+		return KNOT_EOK;
+	}
+
+	if (!ignore_existing || errno != EEXIST) {
+		return knot_map_errno();
+	}
+
+	assert(errno == EEXIST);
+
+	struct stat st = { 0 };
+	if (stat(path, &st) != 0) {
+		return knot_map_errno();
+	}
+
+	if (!S_ISDIR(st.st_mode)) {
+		return knot_map_errno_code(ENOTDIR);
+	}
+
+	return KNOT_EOK;
+}
+
+int make_path(const char *path, mode_t mode)
+{
+	if (path == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	char *dir = strdup(path);
+	if (dir == NULL) {
+		return KNOT_ENOMEM;
+	}
+
+	for (char *p = strchr(dir + 1, '/'); p != NULL; p = strchr(p + 1, '/')) {
+		*p = '\0';
+		if (mkdir(dir, mode) == -1 && errno != EEXIST) {
+			free(dir);
+			return knot_map_errno();
+		}
+		*p = '/';
+	}
+
+	free(dir);
+
+	return KNOT_EOK;
+}
+
+int open_tmp_file(const char *path, char **tmp_name, FILE **file, mode_t mode)
+{
+	int ret;
+
+	*tmp_name = sprintf_alloc("%s.XXXXXX", path);
+	if (*tmp_name == NULL) {
+		ret = KNOT_ENOMEM;
+		goto open_tmp_failed;
+	}
+
+	int fd = mkstemp(*tmp_name);
+	if (fd < 0) {
+		ret = knot_map_errno();
+		goto open_tmp_failed;
+	}
+
+	if (fchmod(fd, mode) != 0) {
+		ret = knot_map_errno();
+		close(fd);
+		unlink(*tmp_name);
+		goto open_tmp_failed;
+	}
+
+	*file = fdopen(fd, "w");
+	if (*file == NULL) {
+		ret = knot_map_errno();
+		close(fd);
+		unlink(*tmp_name);
+		goto open_tmp_failed;
+	}
+
+	return KNOT_EOK;
+open_tmp_failed:
+	free(*tmp_name);
+	*tmp_name = NULL;
+	*file = NULL;
+
+	assert(ret != KNOT_EOK);
+	return ret;
+}
+
+int copy_file(const char *dest, const char *src)
+{
+	if (dest == NULL || src == NULL) {
+		return KNOT_EINVAL;
+	}
+
+	int ret = 0;
+	char *buf = NULL, *tmp_name = NULL;
+	FILE *file = NULL;
+
+	FILE *from = fopen(src, "r");
+	if (from == NULL) {
+		ret = knot_map_errno();
+		goto done;
+	}
+
+	buf = malloc(sizeof(*buf) * BUFSIZE);
+	if (buf == NULL) {
+		ret = KNOT_ENOMEM;
+		goto done;
+	}
+
+	ret = open_tmp_file(dest, &tmp_name, &file, S_IRUSR|S_IWUSR|S_IRGRP|S_IWGRP);
+	if (ret != KNOT_EOK) {
+		goto done;
+	}
+
+	ssize_t cnt;
+	while ((cnt = fread(buf, sizeof(*buf), BUFSIZE, from)) != 0 &&
+	       (ret = (fwrite(buf, sizeof(*buf), cnt, file) == cnt))) {
+	}
+
+	ret = !ret || ferror(from);
+	if (ret != 0) {
+		ret = knot_map_errno();
+		unlink(tmp_name);
+		goto done;
+	}
+
+	ret = rename(tmp_name, dest);
+	if (ret != 0) {
+		ret = knot_map_errno();
+		unlink(tmp_name);
+		goto done;
+	}
+	ret = KNOT_EOK;
+
+done:
+	free(tmp_name);
+	if (file != NULL) {
+		fclose(file);
+	}
+	free(buf);
+	if (from != NULL) {
+		fclose(from);
+	}
+	return ret;
+}