[res] Don't stat asset providers on RO filesystems
IsUpToDate() is one of the most often called functions, let's
make sure it only performs a syscall if it makes any sense and
the underlying file can really change.
Bug: 237583012
Test: build + boot + UTs
Change-Id: Ie5999ddadf10b56f35354d00ad3402b229ffa2c3
diff --git a/libs/androidfw/misc.cpp b/libs/androidfw/misc.cpp
index 5285420..7af5066 100644
--- a/libs/androidfw/misc.cpp
+++ b/libs/androidfw/misc.cpp
@@ -21,12 +21,17 @@
//
#include <androidfw/misc.h>
-#include <sys/stat.h>
-#include <cstring>
-#include <errno.h>
-#include <cstdio>
+#include "android-base/logging.h"
-using namespace android;
+#ifndef _WIN32
+#include <sys/statvfs.h>
+#include <sys/vfs.h>
+#endif // _WIN32
+
+#include <cstring>
+#include <cstdio>
+#include <errno.h>
+#include <sys/stat.h>
namespace android {
@@ -41,8 +46,7 @@
if (errno == ENOENT || errno == ENOTDIR)
return kFileTypeNonexistent;
else {
- fprintf(stderr, "getFileType got errno=%d on '%s'\n",
- errno, fileName);
+ PLOG(ERROR) << "getFileType(): stat(" << fileName << ") failed";
return kFileTypeUnknown;
}
} else {
@@ -82,4 +86,32 @@
return sb.st_mtime;
}
+#ifdef _WIN32
+// No need to implement these for Windows, the functions only matter on a device.
+bool isReadonlyFilesystem(const char*) {
+ return false;
+}
+bool isReadonlyFilesystem(int) {
+ return false;
+}
+#else // _WIN32
+bool isReadonlyFilesystem(const char* path) {
+ struct statfs sfs;
+ if (::statfs(path, &sfs)) {
+ PLOG(ERROR) << "isReadonlyFilesystem(): statfs(" << path << ") failed";
+ return false;
+ }
+ return (sfs.f_flags & ST_RDONLY) != 0;
+}
+
+bool isReadonlyFilesystem(int fd) {
+ struct statfs sfs;
+ if (::fstatfs(fd, &sfs)) {
+ PLOG(ERROR) << "isReadonlyFilesystem(): fstatfs(" << fd << ") failed";
+ return false;
+ }
+ return (sfs.f_flags & ST_RDONLY) != 0;
+}
+#endif // _WIN32
+
}; // namespace android