From: Michael Tremer <michael.tremer@ipfire.org>
Date: Wed, 1 Nov 2023 20:09:22 +0000 (+0000)
Subject: xfer: Implement another version for tmpfiles
X-Git-Tag: 0.9.30~1319
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=8afe94b5dd93ad00f67c425466f94ac01dfa3aee;p=pakfire.git

xfer: Implement another version for tmpfiles

O_TMPFILE requires filesystem support which is sadly not available for
NFS.

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/src/libpakfire/xfer.c b/src/libpakfire/xfer.c
index c6822b90c..c532a0d90 100644
--- a/src/libpakfire/xfer.c
+++ b/src/libpakfire/xfer.c
@@ -60,6 +60,7 @@ struct pakfire_xfer {
 	char url[PATH_MAX];
 	char title[NAME_MAX];
 	char path[PATH_MAX];
+	char tmpfile[PATH_MAX];
 	int tries;
 
 	// POST MIME Object
@@ -103,6 +104,10 @@ struct pakfire_xfer {
 };
 
 static void pakfire_xfer_free(struct pakfire_xfer* xfer) {
+	// Unlink
+	if (*xfer->tmpfile)
+		unlink(xfer->tmpfile);
+
 	// Close any streams
 	if (xfer->fin)
 		fclose(xfer->fin);
@@ -601,6 +606,27 @@ int pakfire_xfer_set_input(struct pakfire_xfer* xfer, FILE* f) {
 	return 0;
 }
 
+static int pakfire_xfer_allocate_tmpfile_legacy(struct pakfire_xfer* xfer, const char* path) {
+	FILE* f = NULL;
+	int r;
+
+	// Compose the path
+	r = pakfire_string_format(xfer->tmpfile, "%s.XXXXXX", path);
+	if (r)
+		return r;
+
+	// Create a temporary file
+	f = pakfire_mktemp(xfer->tmpfile, 0600);
+	if (!f) {
+		CTX_ERROR(xfer->ctx, "Could not open temporary file for %s: %s\n",
+			path, strerror(errno));
+		return -errno;
+	}
+
+	// Set the handle as output
+	return pakfire_xfer_set_output(xfer, f);
+}
+
 static int pakfire_xfer_allocate_tmpfile(struct pakfire_xfer* xfer, const char* path) {
 	char dirname[PATH_MAX];
 	FILE* f = NULL;
@@ -620,9 +646,16 @@ static int pakfire_xfer_allocate_tmpfile(struct pakfire_xfer* xfer, const char*
 	// Open a new temporary file
 	fd = open(dirname, O_TMPFILE|O_RDWR, 0600);
 	if (fd < 0) {
-		CTX_ERROR(xfer->ctx, "Could not open temporary file in %s: %s\n",
-			dirname, strerror(errno));
-		return -errno;
+		switch (errno) {
+			// Fall back to another way for filesystems that don't support O_TMPFILE
+			case ENOTSUP:
+				return pakfire_xfer_allocate_tmpfile_legacy(xfer, path);
+
+			default:
+				CTX_ERROR(xfer->ctx, "Could not open temporary file in %s: %s\n",
+					dirname, strerror(errno));
+				return -errno;
+		}
 	}
 
 	// Turn the file descriptor into a FILE handle
@@ -729,10 +762,18 @@ static int pakfire_xfer_save(struct pakfire_xfer* xfer) {
 	unlink(xfer->path);
 
 	// Move the temporary file to its destination
-	r = linkat(fd, "", AT_FDCWD, xfer->path, AT_EMPTY_PATH);
-	if (r) {
-		CTX_ERROR(xfer->ctx, "Could not link destination file %s: %m\n", xfer->path);
-		return r;
+	if (*xfer->tmpfile) {
+		r = link(xfer->tmpfile, xfer->path);
+		if (r) {
+			CTX_ERROR(xfer->ctx, "Could not link destination file %s: %m\n", xfer->path);
+			return r;
+		}
+	} else {
+		r = linkat(fd, "", AT_FDCWD, xfer->path, AT_EMPTY_PATH);
+		if (r) {
+			CTX_ERROR(xfer->ctx, "Could not link destination file %s: %m\n", xfer->path);
+			return r;
+		}
 	}
 
 	return 0;