From: Michael Tremer <michael.tremer@ipfire.org>
Date: Tue, 31 Dec 2024 12:10:38 +0000 (+0000)
Subject: file: Add function to replace file content from another fd
X-Git-Tag: 0.9.30~640
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=131d27a02e8e00d9931c1eaf9bbdc36feddc2a22;p=pakfire.git

file: Add function to replace file content from another fd

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

diff --git a/src/libpakfire/file.c b/src/libpakfire/file.c
index 144c917d3..141bca85c 100644
--- a/src/libpakfire/file.c
+++ b/src/libpakfire/file.c
@@ -28,6 +28,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <sys/capability.h>
+#include <sys/sendfile.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <time.h>
@@ -1791,3 +1792,42 @@ PAKFIRE_EXPORT int pakfire_file_matches(struct pakfire_file* file, const char* p
 
 	return pakfire_path_match(pattern, path);
 }
+
+int pakfire_file_consume(struct pakfire_file* file, int srcfd) {
+	ssize_t bytes_written = 0;
+	struct stat st = {};
+	int fd = -EBADF;
+	int r;
+
+	// Stat the source
+	r = fstat(srcfd, &st);
+	if (r < 0) {
+		ERROR(file->ctx, "Could not stat the source file descriptor: %m\n");
+		r = -errno;
+		goto ERROR;
+	}
+
+	// Open the file for writing
+	fd = r = pakfire_file_open(file, O_WRONLY|O_TRUNC);
+	if (r < 0)
+		goto ERROR;
+
+	// Write everything to the file
+	bytes_written = sendfile(fd, srcfd, 0, st.st_size);
+	if (bytes_written < st.st_size) {
+		ERROR(file->ctx, "Could not sendfile() to %s: %m\n", pakfire_file_get_path(file));
+		r = -errno;
+		goto ERROR;
+	}
+
+	DEBUG(file->ctx, "Wrote %zd byte(s) to %s\n", bytes_written, pakfire_file_get_abspath(file));
+
+	// Reset r
+	r = 0;
+
+ERROR:
+	if (fd >= 0)
+		close(fd);
+
+	return r;
+}
diff --git a/src/libpakfire/include/pakfire/file.h b/src/libpakfire/include/pakfire/file.h
index 3c2bb104e..07005b0ae 100644
--- a/src/libpakfire/include/pakfire/file.h
+++ b/src/libpakfire/include/pakfire/file.h
@@ -179,5 +179,7 @@ int pakfire_file_matches_class(struct pakfire_file* file, const int class);
 
 int pakfire_file_verify(struct pakfire_file* file, int* status);
 
+int pakfire_file_consume(struct pakfire_file* file, int srcfd);
+
 #endif /* PAKFIRE_PRIVATE */
 #endif /* PAKFIRE_FILE_H */