Merge "Don't remove existing explicitly stashed blocks" (0de2351e) · Commits · e / os / android_bootable_recovery

updater/blockimg.c

+28 −10

Original line number	Diff line number	Diff line
		@@ -635,12 +635,13 @@ lsout:
		}

		static int WriteStash(const char* base, const char* id, int blocks, uint8_t* buffer,
		int checkspace) {
		int checkspace, int *exists) {
		char *fn = NULL;
		char *cn = NULL;
		int fd = -1;
		int rc = -1;
		int res;
		struct stat st;

		if (base == NULL \|\| buffer == NULL) {
		goto wsout;
		@@ -658,6 +659,22 @@ static int WriteStash(const char* base, const char* id, int blocks, uint8_t* buf
		goto wsout;
		}

		if (exists) {
		res = stat(cn, &st);

		if (res == 0) {
		// The file already exists and since the name is the hash of the contents,
		// it's safe to assume the contents are identical (accidental hash collisions
		// are unlikely)
		fprintf(stderr, " skipping %d existing blocks in %s\n", blocks, cn);
		*exists = 1;
		rc = 0;
		goto wsout;
		}

		*exists = 0;
		}

		fprintf(stderr, " writing %d blocks to %s\n", blocks, cn);

		fd = TEMP_FAILURE_RETRY(open(fn, O_WRONLY \| O_CREAT \| O_TRUNC \| O_SYNC, STASH_FILE_MODE));
		@@ -821,7 +838,7 @@ static int SaveStash(const char* base, char wordsave, uint8_t buffer, size_t
		}

		fprintf(stderr, "stashing %d blocks to %s\n", blocks, id);
		return WriteStash(base, id, blocks, *buffer, 0);
		return WriteStash(base, id, blocks, *buffer, 0, NULL);
		}

		static int FreeStash(const char* base, const char* id) {
		@@ -997,6 +1014,7 @@ static int LoadSrcTgtVersion3(CommandParameters* params, RangeSet** tgt, int* sr
		int onehash, int* overlap) {
		char* srchash = NULL;
		char* tgthash = NULL;
		int stash_exists = 0;
		int overlap_blocks = 0;
		int rc = -1;
		uint8_t* tgtbuffer = NULL;
		@@ -1052,14 +1070,17 @@ static int LoadSrcTgtVersion3(CommandParameters* params, RangeSet** tgt, int* sr
		fprintf(stderr, "stashing %d overlapping blocks to %s\n", *src_blocks,
		srchash);

		if (WriteStash(params->stashbase, srchash, *src_blocks, params->buffer, 1) != 0) {
		if (WriteStash(params->stashbase, srchash, *src_blocks, params->buffer, 1,
		&stash_exists) != 0) {
		fprintf(stderr, "failed to stash overlapping source blocks\n");
		goto v3out;
		}

		// Can be deleted when the write has completed
		if (!stash_exists) {
		params->freestash = srchash;
		}
		}

		// Source blocks have expected content, command can proceed
		rc = 0;
		@@ -1068,12 +1089,9 @@ static int LoadSrcTgtVersion3(CommandParameters* params, RangeSet** tgt, int* sr

		if (*overlap && LoadStash(params->stashbase, srchash, 1, NULL, &params->buffer,
		&params->bufsize, 1) == 0) {
		// Overlapping source blocks were previously stashed, command can proceed
		if (params->canwrite) {
		// We didn't create the stash, so delete after write only if we will
		// actually perform the write
		params->freestash = srchash;
		}
		// Overlapping source blocks were previously stashed, command can proceed.
		// We are recovering from an interrupted command, so we don't know if the
		// stash can safely be deleted after this command.
		rc = 0;
		goto v3out;
		}