From 1d87b938cd4fa2cac1dd51d2493c3eebf4ada94e Mon Sep 17 00:00:00 2001
From: Eric Biggers <ebiggers3@gmail.com>
Date: Tue, 9 Apr 2013 11:14:46 -0500
Subject: [PATCH 1/1] Save original xml_data only when needed

---
 src/wim.c             |  4 +---
 src/wimlib_internal.h |  3 ---
 src/xml.c             | 40 ++++++++++++++++++++++++++--------------
 src/xml.h             |  1 -
 4 files changed, 27 insertions(+), 21 deletions(-)

diff --git a/src/wim.c b/src/wim.c
index a5044c68..9bc02556 100644
--- a/src/wim.c
+++ b/src/wim.c
@@ -470,8 +470,7 @@ begin_read(WIMStruct *w, const tchar *in_wim_path, int open_flags,
 	if (ret)
 		return ret;
 
-	ret = read_xml_data(w->fp, &w->hdr.xml_res_entry,
-			    &w->xml_data, &w->wim_info);
+	ret = read_xml_data(w->fp, &w->hdr.xml_res_entry, &w->wim_info);
 	if (ret)
 		return ret;
 
@@ -664,7 +663,6 @@ wimlib_free(WIMStruct *w)
 	free_lookup_table(w->lookup_table);
 
 	FREE(w->filename);
-	FREE(w->xml_data);
 	free_wim_info(w->wim_info);
 	if (w->image_metadata) {
 		for (unsigned i = 0; i < w->hdr.image_count; i++)
diff --git a/src/wimlib_internal.h b/src/wimlib_internal.h
index 6396c00a..8f4d2958 100644
--- a/src/wimlib_internal.h
+++ b/src/wimlib_internal.h
@@ -295,9 +295,6 @@ struct WIMStruct {
 	/* The lookup table for the WIM file. */
 	struct wim_lookup_table *lookup_table;
 
-	/* Pointer to the XML data read from the WIM file (UTF16LE-encoded). */
-	utf16lechar *xml_data;
-
 	/* Information retrieved from the XML data, arranged in an orderly
 	 * manner. */
 	struct wim_info *wim_info;
diff --git a/src/xml.c b/src/xml.c
index ff37757f..f1891833 100644
--- a/src/xml.c
+++ b/src/xml.c
@@ -1237,7 +1237,7 @@ libxml_global_cleanup()
  */
 int
 read_xml_data(FILE *fp, const struct resource_entry *res_entry,
-	      utf16lechar **xml_data_ret, struct wim_info **info_ret)
+	      struct wim_info **info_ret)
 {
 	utf16lechar *xml_data;
 	xmlDoc *doc;
@@ -1267,7 +1267,7 @@ read_xml_data(FILE *fp, const struct resource_entry *res_entry,
 
 	ret = read_uncompressed_resource(fp, res_entry->offset,
 					 res_entry->size, xml_data);
-	if (ret != 0)
+	if (ret)
 		goto out_free_xml_data;
 
 	/* Null-terminate just in case */
@@ -1300,13 +1300,7 @@ read_xml_data(FILE *fp, const struct resource_entry *res_entry,
 		ret = WIMLIB_ERR_XML;
 		goto out_free_doc;
 	}
-
 	ret = xml_read_wim_info(root, info_ret);
-	if (ret != 0)
-		goto out_free_doc;
-
-	*xml_data_ret = xml_data;
-	xml_data = NULL;
 out_free_doc:
 	DEBUG("Freeing XML tree.");
 	xmlFreeDoc(doc);
@@ -1493,15 +1487,33 @@ WIMLIBAPI int
 wimlib_extract_xml_data(WIMStruct *w, FILE *fp)
 {
 	size_t bytes_written;
+	size_t size;
+	void *buf;
+	int ret;
 
-	if (!w->xml_data)
-		return WIMLIB_ERR_INVALID_PARAM;
-	bytes_written = fwrite(w->xml_data, 1, w->hdr.xml_res_entry.size, fp);
-	if (bytes_written != w->hdr.xml_res_entry.size) {
+	size = w->hdr.xml_res_entry.size;
+	if (sizeof(size_t) < sizeof(u64))
+		if (size != w->hdr.xml_res_entry.size)
+			return WIMLIB_ERR_INVALID_PARAM;
+
+	buf = MALLOC(size);
+	if (!buf)
+		return WIMLIB_ERR_NOMEM;
+
+	ret = read_uncompressed_resource(w->fp, w->hdr.xml_res_entry.offset,
+					 size, buf);
+	if (ret)
+		goto out_free_buf;
+
+	if (fwrite(buf, 1, size, fp) != size) {
 		ERROR_WITH_ERRNO("Failed to extract XML data");
-		return WIMLIB_ERR_WRITE;
+		ret = WIMLIB_ERR_WRITE;
+	} else {
+		ret = 0;
 	}
-	return 0;
+out_free_buf:
+	FREE(buf);
+	return ret;
 }
 
 /* Sets the name of an image in the WIM. */
diff --git a/src/xml.h b/src/xml.h
index 070dada5..80965faf 100644
--- a/src/xml.h
+++ b/src/xml.h
@@ -39,7 +39,6 @@ print_image_info(const struct wim_info *wim_info, int image);
 
 extern int
 read_xml_data(FILE *fp, const struct resource_entry *res,
-	      utf16lechar **xml_data_ret,
 	      struct wim_info **info_ret);
 
 extern int
-- 
2.43.0