Add OBB flags to support overlays
* Add flags field in OBB footer to support overlays.
* Remove unused 'crypto' and 'filesystem' fields in obbtool (could
later be supported in the "flags" field of the OBB footer).
* Add notes to document OBB classes before shipping.
Change-Id: I386b43c32c5edef55210acb5d3322639c08010ba
diff --git a/libs/utils/ObbFile.cpp b/libs/utils/ObbFile.cpp
index adedf0c..e170ab8 100644
--- a/libs/utils/ObbFile.cpp
+++ b/libs/utils/ObbFile.cpp
@@ -29,12 +29,13 @@
#define kFooterTagSize 8 /* last two 32-bit integers */
-#define kFooterMinSize 21 /* 32-bit signature version
- * 32-bit package version
- * 32-bit package name size
- * 1-character package name
- * 32-bit footer size
- * 32-bit footer marker
+#define kFooterMinSize 25 /* 32-bit signature version (4 bytes)
+ * 32-bit package version (4 bytes)
+ * 32-bit flags (4 bytes)
+ * 32-bit package name size (4-bytes)
+ * >=1-character package name (1 byte)
+ * 32-bit footer size (4 bytes)
+ * 32-bit footer marker (4 bytes)
*/
#define kMaxBufSize 32768 /* Maximum file read buffer */
@@ -45,8 +46,9 @@
/* offsets in version 1 of the header */
#define kPackageVersionOffset 4
-#define kPackageNameLenOffset 8
-#define kPackageNameOffset 12
+#define kFlagsOffset 8
+#define kPackageNameLenOffset 12
+#define kPackageNameOffset 16
/*
* TEMP_FAILURE_RETRY is defined by some, but not all, versions of
@@ -78,7 +80,10 @@
namespace android {
ObbFile::ObbFile() :
- mVersion(-1) {
+ mPackageName(""),
+ mVersion(-1),
+ mFlags(0)
+{
}
ObbFile::~ObbFile() {
@@ -199,6 +204,7 @@
}
mVersion = (int32_t) get4LE((unsigned char*)scanBuf + kPackageVersionOffset);
+ mFlags = (int32_t) get4LE((unsigned char*)scanBuf + kFlagsOffset);
uint32_t packageNameLen = get4LE((unsigned char*)scanBuf + kPackageNameLenOffset);
if (packageNameLen <= 0
@@ -268,6 +274,12 @@
return false;
}
+ put4LE(intBuf, mFlags);
+ if (write(fd, &intBuf, sizeof(uint32_t)) != (ssize_t)sizeof(uint32_t)) {
+ LOGW("couldn't write package version");
+ return false;
+ }
+
size_t packageNameLen = mPackageName.size();
put4LE(intBuf, packageNameLen);
if (write(fd, &intBuf, sizeof(uint32_t)) != (ssize_t)sizeof(uint32_t)) {
@@ -280,7 +292,7 @@
return false;
}
- put4LE(intBuf, 3*sizeof(uint32_t) + packageNameLen);
+ put4LE(intBuf, kPackageNameOffset + packageNameLen);
if (write(fd, &intBuf, sizeof(uint32_t)) != (ssize_t)sizeof(uint32_t)) {
LOGW("couldn't write footer size: %s", strerror(errno));
return false;