From: Michael Tremer <michael.tremer@ipfire.org>
Date: Thu, 20 May 2021 17:23:37 +0000 (+0000)
Subject: archive: Make files sticky
X-Git-Tag: 0.9.28~1285^2~119
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=f99c69bb7f9b6ecfb0af44ed4a5511257e2708df;p=pakfire.git

archive: Make files sticky

We can now return to open the archive file once and keep it opened. This
makes files sticky and nobody can replace or delete a file
mid-transaction.

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

diff --git a/src/libpakfire/archive.c b/src/libpakfire/archive.c
index 783020e17..7bc5173d5 100644
--- a/src/libpakfire/archive.c
+++ b/src/libpakfire/archive.c
@@ -65,8 +65,9 @@ struct _PakfireArchive {
 	Pakfire pakfire;
 	int nrefs;
 
-	PakfirePackage package;
 	char path[PATH_MAX];
+	FILE* f;
+	PakfirePackage package;
 
 	// metadata
 	unsigned int format;
@@ -94,7 +95,20 @@ struct _PakfireArchiveSignature {
 	int nrefs;
 };
 
-static int archive_open(PakfireArchive archive, struct archive** a) {
+/*
+	A helper function to close the archive and reset our data structures
+*/
+static void close_archive(PakfireArchive archive, struct archive* a) {
+	archive_read_free(a);
+
+	// Rewind the file descriptor
+	rewind(archive->f);
+}
+
+/*
+	A helper function that opens the archive for reading
+*/
+static int open_archive(PakfireArchive archive, struct archive** a) {
 	*a = archive_read_new();
 	if (!*a)
 		return ENOMEM;
@@ -103,16 +117,21 @@ static int archive_open(PakfireArchive archive, struct archive** a) {
 	archive_read_support_format_tar(*a);
 
 	// Try opening the archive file
-	int r = archive_read_open_filename(*a, archive->path, 8192);
+	int r = archive_read_open_FILE(*a, archive->f);
 	if (r) {
 		ERROR(archive->pakfire, "Could not open archive %s: %s\n",
 			archive->path, archive_error_string(*a));
-		archive_read_free(*a);
-		*a = NULL;
-		return r;
+		goto ERROR;
 	}
 
+	// Success
 	return 0;
+
+ERROR:
+	close_archive(archive, *a);
+	*a = NULL;
+
+	return r;
 }
 
 static int find_archive_entry(struct archive_entry** entry, struct archive* a, const char* filename) {
@@ -336,6 +355,10 @@ static void pakfire_archive_free_chksums(PakfireArchive archive) {
 static void pakfire_archive_free(PakfireArchive archive) {
 	DEBUG(archive->pakfire, "Releasing archive at %p\n", archive);
 
+	// Close the file
+	if (archive->f)
+		fclose(archive->f);
+
 	// Free all checksums
 	pakfire_archive_free_chksums(archive);
 
@@ -428,7 +451,7 @@ static int pakfire_archive_parse_metadata(PakfireArchive archive) {
 		return 0;
 
 	// Open the archive
-	int r = archive_open(archive, &a);
+	int r = open_archive(archive, &a);
 	if (r)
 		goto ERROR;
 
@@ -602,7 +625,7 @@ static int pakfire_archive_walk(PakfireArchive archive,
 	struct archive* a;
 
 	// Open the archive file
-	int r = archive_open(archive, &a);
+	int r = open_archive(archive, &a);
 	if (r)
 		return r;
 
@@ -689,9 +712,14 @@ static int pakfire_archive_try_open(PakfireArchive archive, const char* path) {
 	// Store path
 	pakfire_string_set(archive->path, path);
 
+	// Open the file (and keep the file descriptor open)
+	archive->f = fopen(archive->path, "r");
+	if (!archive->f)
+		return 1;
+
 	// Open the archive file for reading.
 	struct archive* a = NULL;
-	int r = archive_open(archive, &a);
+	int r = open_archive(archive, &a);
 	if (r)
 		goto ERROR;
 
@@ -749,7 +777,7 @@ PAKFIRE_EXPORT int pakfire_archive_read(PakfireArchive archive, const char* file
 	while (*filename == '/')
 		filename++;
 
-	int r = archive_open(archive, &a);
+	int r = open_archive(archive, &a);
 	if (r)
 		goto ERROR;
 
@@ -952,7 +980,7 @@ PAKFIRE_EXPORT int pakfire_archive_extract(PakfireArchive archive, const char* p
 		goto ERROR;
 
 	// Open the archive
-	r = archive_open(archive, &a);
+	r = open_archive(archive, &a);
 	if (r)
 		goto ERROR;
 
@@ -1044,7 +1072,7 @@ static int pakfire_archive_load_filelist(PakfireArchive archive) {
 	int r;
 
 	// Open the archive
-	r = archive_open(archive, &a);
+	r = open_archive(archive, &a);
 	if (r)
 		goto ERROR;
 
@@ -1347,7 +1375,7 @@ PAKFIRE_EXPORT pakfire_archive_verify_status_t pakfire_archive_verify(PakfireArc
 
 	// Open the archive file
 	struct archive* a;
-	int r = archive_open(archive, &a);
+	int r = open_archive(archive, &a);
 	if (r)
 		return PAKFIRE_ARCHIVE_VERIFY_ERROR;