Handle non-inline files that need to be EROFS_INODE_CHUNK_BASED

Signed-off-by: Colin Walters <[email protected]>

libcomposefs/lcfs-writer-erofs.c

@@ -638,6 +638,7 @@ static uint64_t compute_erofs_inode_padding_for_tail(struct lcfs_node_s *node,
 		/* Didn't fit, don't inline the tail. */
 		node->erofs_n_blocks++;
 		node->erofs_tailsize = 0;
+		return round_up(pos, EROFS_BLKSIZ) - pos;
 	}
 
 	return 0;
@@ -817,6 +818,17 @@ static int write_erofs_dentries(struct lcfs_ctx_s *ctx, struct lcfs_node_s *node
 	return 0;
 }
 
+static int write_empty_chunks(struct lcfs_ctx_s *ctx, uint32_t chunk_count)
+{
+	for (size_t i = 0; i < chunk_count; i++) {
+		uint32_t empty_chunk = 0xFFFFFFFF;
+		int ret = lcfs_write(ctx, &empty_chunk, sizeof(empty_chunk));
+		if (ret < 0)
+			return ret;
+	}
+	return 0;
+}
+
 static int write_erofs_inode_data(struct lcfs_ctx_s *ctx, struct lcfs_node_s *node)
 {
 	struct lcfs_ctx_erofs_s *ctx_erofs = (struct lcfs_ctx_erofs_s *)ctx;
@@ -1012,28 +1024,23 @@ static int write_erofs_inode_data(struct lcfs_ctx_s *ctx, struct lcfs_node_s *no
 			if (ret < 0)
 				return ret;
 		}
-	} else if (type == S_IFREG) {
+	} else if (type == S_IFREG && node->erofs_tailsize > 0) {
 		if (node->content != NULL) {
-			if (node->erofs_tailsize) {
 				uint64_t file_size = node->inode.st_size;
 				ret = lcfs_write(ctx,
 						 node->content + file_size -
 							 node->erofs_tailsize,
 						 node->erofs_tailsize);
 				if (ret < 0)
 					return ret;
-			}
 		} else {
 			// Currently we assume this fits within a single block
 			assert(chunk_count <= LCFS_MAX_NONINLINE_CHUNKS);
 			assert(node->erofs_n_blocks == 0 ||
 			       node->erofs_n_blocks == 1);
-			for (size_t i = 0; i < chunk_count; i++) {
-				uint32_t empty_chunk = 0xFFFFFFFF;
-				ret = lcfs_write(ctx, &empty_chunk,
-						 sizeof(empty_chunk));
-				if (ret < 0)
-					return ret;
+			ret = write_empty_chunks(ctx, chunk_count);
+			if (ret < 0) {
+				return ret;
 			}
 		}
 	}
@@ -1071,7 +1078,21 @@ static int write_erofs_file_content(struct lcfs_ctx_s *ctx, struct lcfs_node_s *
 	uint8_t *target;
 	bool has_blocks = node->erofs_n_blocks > 0;
 	if (type == S_IFREG && has_blocks) {
-		assert(node->content != NULL);
+		// If this is a non-inline file, then we need to write at most
+		// a single block-sized chunk.
+		if (node->content == NULL) {
+			assert(node->erofs_tailsize == 0);
+			uint32_t chunkbits;
+			uint32_t chunk_count;
+			erofs_compute_chunking(node->inode.st_size, &chunkbits,
+					       &chunk_count);
+			// Currently we assume this fits within a single block
+			assert(chunk_count <= LCFS_MAX_NONINLINE_CHUNKS);
+			assert(node->erofs_n_blocks == 1);
+			// Note early return here
+			return write_empty_chunks(ctx, chunk_count);
+		}
+		// If it's an inline file, provide the content to write
 		target = node->content;
 	} else if (type == S_IFLNK && has_blocks) {
 		assert(node->payload != NULL);

tests/assets/bigfile-xattr.dump

@@ -0,0 +1,2 @@
+/ 4096 40755 2 0 0 0 0.0 - - -
+/bigfile 9001899274941000 100777 1 0 0 0 0.0 - - - user.foo=

tests/assets/bigfile-xattr.dump.sha256

@@ -0,0 +1 @@
+5bdb37d78dcf03b4ab1adc9a2d5212d3d95213b41628939f5fe3769f93d927cc

tests/meson.build

@@ -5,6 +5,7 @@ test_assets_small = [
   'special.dump',
   'longlink.dump',
   'bigfile.dump',
+  'bigfile-xattr.dump',
   'special_v1.dump',
   'honggfuzz-long-symlink.dump',
   'no-newline.dump',