main: Split outer and inner archive initialization

Thus, we can both read the control file and list data files in one pass
through the outer archive.  Unlike dpkg-deb, opkg-opk will allow both -I
and -c options (commands in dpkg-deb syntax) to be used together.

1 files changed, 103 insertions, 67 deletions

diff --git a/src/main.c b/src/main.c
index e2496aa..3b80e8e 100644
--- a/src/main.c
+++ b/src/main.c
@@ -28,22 +28,28 @@
 
 #define OPKG_OPK_MAIN_FILE_BUFFER_SIZE_ 8192
 
-struct _opkg_opk_main_file {
-	FILE *file;
-	char  buffer[OPKG_OPK_MAIN_FILE_BUFFER_SIZE_];
+struct _opkg_opk_main_opk {
+	FILE                  *file;
+	char                   file_buffer[OPKG_OPK_MAIN_FILE_BUFFER_SIZE_];
+	struct opkg_opk_gzip  *outer_gzip;
+	struct opkg_opk_ustar *outer_ustar;
+	char                  *version_buffer;
+	size_t                 version_size;
+	struct opkg_opk_gzip  *inner_gzip;
+	struct opkg_opk_ustar *inner_ustar;
 };
 
 static int
 _opkg_opk_main_file_read(void *user_data, char **buffer, size_t *size)
 {
-	struct _opkg_opk_main_file *file = user_data;
+	struct _opkg_opk_main_opk *opk = user_data;
 
-	*buffer = file->buffer;
-	*size   = fread(file->buffer, 1, OPKG_OPK_MAIN_FILE_BUFFER_SIZE_,
-			file->file);
-	if (feof(file->file)) {
+	*buffer = opk->file_buffer;
+	*size   = fread(opk->file_buffer, 1, OPKG_OPK_MAIN_FILE_BUFFER_SIZE_,
+			opk->file);
+	if (feof(opk->file)) {
 		return OPKG_OPK_END;
-	} else if (ferror(file->file) || *size == 0) {
+	} else if (ferror(opk->file) || *size == 0) {
 		return OPKG_OPK_ERROR;
 	} else {
 		return OPKG_OPK_OK;
@@ -51,103 +57,101 @@ _opkg_opk_main_file_read(void *user_data, char **buffer, size_t *size)
 }
 
 static int
-_opkg_opk_main_extract(const char *file_name, const char *outer_member,
-		int (*inner_action)(struct opkg_opk_ustar *))
+_opkg_opk_main_init_outer(struct _opkg_opk_main_opk *opk, const char *file_name)
 {
-	struct _opkg_opk_main_file    file;
-	struct opkg_opk_gzip         *outer_gzip;
-	struct opkg_opk_ustar        *outer_ustar;
-	char                         *buffer;
-	size_t                        size;
-	struct opkg_opk_gzip         *inner_gzip;
-	struct opkg_opk_ustar        *inner_ustar;
-
 	/* Open outer archive. */
-	file.file = fopen(file_name, "rb");
-	if (file.file == NULL) {
+	opk->file = fopen(file_name, "rb");
+	if (opk->file == NULL) {
 		fprintf(stderr, "Error: Failed to open file \"%s\"\n",
 				file_name);
 		goto error0;
 	}
 
 	/* Initialize outer gzip decompressor. */
-	outer_gzip = opkg_opk_gzip_init(&_opkg_opk_main_file_read, &file);
-	if (outer_gzip == NULL) {
+	opk->outer_gzip = opkg_opk_gzip_init(&_opkg_opk_main_file_read, opk);
+	if (opk->outer_gzip == NULL) {
 		fputs("Error: Failed to initialize\n", stderr);
 		goto error1;
 	}
 
 	/* Initialize outer ustar unarchiver. */
-	outer_ustar = opkg_opk_ustar_init(outer_gzip);
-	if (outer_ustar == NULL) {
+	opk->outer_ustar = opkg_opk_ustar_init(opk->outer_gzip);
+	if (opk->outer_ustar == NULL) {
 		fputs("Error: Failed to initialize\n", stderr);
 		goto error2;
 	}
 
 	/* Check package version. */
-	if (opkg_opk_ustar_seek(outer_ustar, 1, "debian-binary") !=
+	if (opkg_opk_ustar_seek(opk->outer_ustar, 1, "debian-binary") !=
 			OPKG_OPK_OK) {
 		fputs("Error: Failed to find \"debian-binary\" in archive\n",
 				stderr);
 		goto error3;
 	}
-	if (opkg_opk_ustar_read(outer_ustar, &buffer, &size) != OPKG_OPK_OK) {
+	if (opkg_opk_ustar_read(opk->outer_ustar,
+				&opk->version_buffer, &opk->version_size) !=
+			OPKG_OPK_OK) {
 		fputs("Error: Failed to read \"debian-binary\" in archive\n",
 				stderr);
 		goto error3;
 	}
-	if (size < 4 || strncmp(buffer, "2.", 2) != 0) {
+	if (opk->version_size < 4 || strncmp(opk->version_buffer, "2.", 2) != 0)
+	{
 		fputs("Error: Unsupported package version\n", stderr);
 		goto error3;
 	}
 
+	return OPKG_OPK_OK;
+
+ error3:
+	opkg_opk_ustar_free(opk->outer_ustar);
+ error2:
+	opkg_opk_gzip_free(opk->outer_gzip);
+ error1:
+	fclose(opk->file);
+ error0:
+	return OPKG_OPK_ERROR;
+}
+
+static int
+_opkg_opk_main_init_inner(struct _opkg_opk_main_opk *opk, const char *member)
+{
+	int ret;
+
+	/* Finish reading previous inner archive, if any. */
+	while ((ret = opkg_opk_ustar_read(opk->outer_ustar, NULL, NULL)) ==
+			OPKG_OPK_OK);
+	if (ret == OPKG_OPK_ERROR) {
+		fputs("Error: Failed to read archive\n", stderr);
+		return OPKG_OPK_ERROR;
+	}
+
 	/* Find requested inner archive. */
-	if (opkg_opk_ustar_seek(outer_ustar, 1, outer_member) != OPKG_OPK_OK) {
+	if (opkg_opk_ustar_seek(opk->outer_ustar, 1, member) !=
+			OPKG_OPK_OK) {
 		fprintf(stderr, "Error: Failed to find \"%s\" in archive\n",
-				outer_member);
-		goto error3;
+				member);
+		return OPKG_OPK_ERROR;
 	}
 
 	/* Initialize inner gzip decompressor. */
-	inner_gzip = opkg_opk_gzip_init(
+	opk->inner_gzip = opkg_opk_gzip_init(
 			(opkg_opk_gzip_read_func *) &opkg_opk_ustar_read,
-			outer_ustar);
-	if (inner_gzip == NULL) {
+			opk->outer_ustar);
+	if (opk->inner_gzip == NULL) {
 		fputs("Error: Failed to initialize\n", stderr);
-		goto error3;
+		return OPKG_OPK_ERROR;
 	}
 
 	/* Initialize inner ustar unarchiver. */
-	inner_ustar = opkg_opk_ustar_init(inner_gzip);
-	if (inner_ustar == NULL) {
+	opk->inner_ustar = opkg_opk_ustar_init(opk->inner_gzip);
+	if (opk->inner_ustar == NULL) {
 		fputs("Error: Failed to initialize\n", stderr);
-		goto error4;
-	}
-
-	/* Read control file or list data files. */
-	if (inner_action(inner_ustar) != OPKG_OPK_OK) {
-		goto error5;
+		opkg_opk_gzip_free(opk->inner_gzip);
+		return OPKG_OPK_ERROR;
 	}
 
-	opkg_opk_ustar_free(inner_ustar);
-	opkg_opk_gzip_free(inner_gzip);
-	opkg_opk_ustar_free(outer_ustar);
-	opkg_opk_gzip_free(outer_gzip);
-	fclose(file.file);
 	return OPKG_OPK_OK;
-
- error5:
-	opkg_opk_ustar_free(inner_ustar);
- error4:
-	opkg_opk_gzip_free(inner_gzip);
- error3:
-	opkg_opk_ustar_free(outer_ustar);
- error2:
-	opkg_opk_gzip_free(outer_gzip);
- error1:
-	fclose(file.file);
- error0:
-	return OPKG_OPK_ERROR;
 }
 
 static int
@@ -255,15 +259,47 @@ _opkg_opk_main_list_members(struct opkg_opk_ustar *ustar)
 int
 main(int argc, char *argv[])
 {
-	if (_opkg_opk_main_extract(argv[1], "control.tar.gz",
-			&_opkg_opk_main_read_control) != OPKG_OPK_OK) {
-		return EXIT_FAILURE;
+	struct _opkg_opk_main_opk  opk;
+
+	/* Initialize outer archive. */
+	if (_opkg_opk_main_init_outer(&opk, argv[1]) != OPKG_OPK_OK) {
+		goto error0;
+	}
+
+	/* Read control file. */
+	if (_opkg_opk_main_init_inner(&opk, "control.tar.gz") != OPKG_OPK_OK) {
+		goto error1;
+	}
+	if (_opkg_opk_main_read_control(opk.inner_ustar) != OPKG_OPK_OK) {
+		goto error2;
 	}
+	opkg_opk_ustar_free(opk.inner_ustar);
+	opkg_opk_gzip_free(opk.inner_gzip);
+
 	puts("");
-	if (_opkg_opk_main_extract(argv[1], "data.tar.gz",
-			&_opkg_opk_main_list_members) != OPKG_OPK_OK) {
-		return EXIT_FAILURE;
+
+	/* List data files. */
+	if (_opkg_opk_main_init_inner(&opk, "data.tar.gz") != OPKG_OPK_OK) {
+		goto error1;
 	}
+	if (_opkg_opk_main_list_members(opk.inner_ustar) != OPKG_OPK_OK) {
+		goto error2;
+	}
+	opkg_opk_ustar_free(opk.inner_ustar);
+	opkg_opk_gzip_free(opk.inner_gzip);
 
+	opkg_opk_ustar_free(opk.outer_ustar);
+	opkg_opk_gzip_free(opk.outer_gzip);
+	fclose(opk.file);
 	return EXIT_SUCCESS;
+
+ error2:
+	opkg_opk_ustar_free(opk.inner_ustar);
+	opkg_opk_gzip_free(opk.inner_gzip);
+ error1:
+	opkg_opk_ustar_free(opk.outer_ustar);
+	opkg_opk_gzip_free(opk.outer_gzip);
+	fclose(opk.file);
+ error0:
+	return EXIT_FAILURE;
 }