tar: make checksumming of inner files conditional

and force checksumming only when unpacking archive. otherwise
it's extra computation for nothing.

src/apk_archive.h

@@ -20,8 +20,11 @@ typedef int (*apk_archive_entry_parser)(void *ctx,
 					const struct apk_file_info *ae,
 					struct apk_istream *istream);
 
-int apk_tar_parse(struct apk_istream *, apk_archive_entry_parser parser, void *ctx);
+int apk_tar_parse(struct apk_istream *,
-int apk_tar_write_entry(struct apk_ostream *, const struct apk_file_info *ae, char *data);
+		  apk_archive_entry_parser parser, void *ctx,
+		  int soft_checksums);
+int apk_tar_write_entry(struct apk_ostream *, const struct apk_file_info *ae,
+			char *data);
 int apk_tar_write_padding(struct apk_ostream *, const struct apk_file_info *ae);
 
 int apk_archive_entry_extract(const struct apk_file_info *ae,

src/archive.c

@@ -114,7 +114,7 @@ static void tar_entry_close(void *stream)
 }
 
 int apk_tar_parse(struct apk_istream *is, apk_archive_entry_parser parser,
-		  void *ctx)
+		  void *ctx, int soft_checksums)
 {
 	struct apk_file_info entry;
 	struct apk_tar_entry_istream teis = {
@@ -152,6 +152,7 @@ int apk_tar_parse(struct apk_istream *is, apk_archive_entry_parser parser,
 			.device = makedev(GET_OCTAL(buf.devmajor),
 					  GET_OCTAL(buf.devminor)),
 		};
+		teis.csum = NULL;
 
 		switch (buf.typeflag) {
 		case 'L':
@@ -170,8 +171,7 @@ int apk_tar_parse(struct apk_istream *is, apk_archive_entry_parser parser,
 			    di->size <= sizeof(entry.csum.data)) {
 				entry.csum.type = di->size;
 				memcpy(entry.csum.data, di->digest, di->size);
-				teis.csum = NULL;
+			} else if (soft_checksums) {
-			} else {
 				teis.csum = &entry.csum;
 			}
 			break;
@@ -202,7 +202,10 @@ int apk_tar_parse(struct apk_istream *is, apk_archive_entry_parser parser,
 				entry.name = strdup(buf.name);
 
 			/* callback parser function */
-			EVP_DigestInit_ex(&teis.mdctx, apk_default_checksum(), NULL);
+			if (teis.csum != NULL)
+				EVP_DigestInit_ex(&teis.mdctx,
+						  apk_default_checksum(), NULL);
+
 			r = parser(ctx, &entry, &teis.is);
 			free(entry.name);
 			if (r != 0)

src/database.c

@@ -706,7 +706,8 @@ static int apk_db_read_state(struct apk_database *db, int flags)
 	if (!(flags & APK_OPENF_NO_SCRIPTS)) {
 		is = apk_istream_from_file("var/lib/apk/scripts.tar");
 		if (is != NULL) {
-			apk_tar_parse(is, apk_read_script_archive_entry, db);
+			apk_tar_parse(is, apk_read_script_archive_entry, db,
+				      FALSE);
 		} else {
 			is = apk_istream_from_file("var/lib/apk/scripts");
 			if (is != NULL)
@@ -1119,7 +1120,7 @@ int apk_cache_download(struct apk_database *db, struct apk_checksum *csum,
 		apk_sign_ctx_init(&sctx, APK_SIGN_VERIFY, NULL);
 		is = apk_bstream_gunzip_mpart(apk_bstream_from_file(tmp2),
 			apk_sign_ctx_mpart_cb, &sctx);
-		r = apk_tar_parse(is, apk_sign_ctx_verify_tar, &sctx);
+		r = apk_tar_parse(is, apk_sign_ctx_verify_tar, &sctx, FALSE);
 		is->close(is);
 		apk_sign_ctx_free(&sctx);
 		if (r != 0) {
@@ -1224,7 +1225,7 @@ static int load_index(struct apk_database *db, struct apk_bstream *bs,
 		ctx.found = 0;
 		apk_sign_ctx_init(&ctx.sctx, APK_SIGN_VERIFY, NULL);
 		is = apk_bstream_gunzip_mpart(bs, apk_sign_ctx_mpart_cb, &ctx.sctx);
-		r = apk_tar_parse(is, load_apkindex, &ctx);
+		r = apk_tar_parse(is, load_apkindex, &ctx, FALSE);
 		is->close(is);
 		apk_sign_ctx_free(&ctx.sctx);
 		if (ctx.found == 0)
@@ -1639,7 +1640,7 @@ static int apk_db_unpack_pkg(struct apk_database *db,
 	};
 	apk_sign_ctx_init(&ctx.sctx, APK_SIGN_VERIFY_IDENTITY, &newpkg->csum);
 	tar = apk_bstream_gunzip_mpart(bs, apk_sign_ctx_mpart_cb, &ctx.sctx);
-	r = apk_tar_parse(tar, apk_db_install_archive_entry, &ctx);
+	r = apk_tar_parse(tar, apk_db_install_archive_entry, &ctx, TRUE);
 	apk_sign_ctx_free(&ctx.sctx);
 	tar->close(tar);
 

src/package.c

@@ -713,7 +713,7 @@ int apk_pkg_read(struct apk_database *db, const char *file,
 	ctx.pkg->size = fi.size;
 
 	tar = apk_bstream_gunzip_mpart(bs, apk_sign_ctx_mpart_cb, sctx);
-	r = apk_tar_parse(tar, read_info_entry, &ctx);
+	r = apk_tar_parse(tar, read_info_entry, &ctx, FALSE);
 	tar->close(tar);
 	if (r < 0 && r != -ECANCELED)
 		goto err;

src/verify.c

@@ -25,7 +25,7 @@ static int verify_main(void *ctx, int argc, char **argv)
 		apk_sign_ctx_init(&sctx, APK_SIGN_VERIFY, NULL);
 		is = apk_bstream_gunzip_mpart(apk_bstream_from_file(argv[i]),
 					      apk_sign_ctx_mpart_cb, &sctx);
-		r = apk_tar_parse(is, apk_sign_ctx_verify_tar, &sctx);
+		r = apk_tar_parse(is, apk_sign_ctx_verify_tar, &sctx, FALSE);
 		is->close(is);
 		ok = sctx.control_verified && sctx.data_verified;
 		if (apk_verbosity >= 1)