nsresult
OpenStorageFile(const nsCString& aRecordName,
const nsString& aNodeId,
const OpenFileMode aMode,
PRFileDesc** aOutFD)
{
MOZ_ASSERT(aOutFD);
nsCOMPtr<nsIFile> f;
nsresult rv = GetGMPStorageDir(getter_AddRefs(f), aNodeId);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
nsAutoString recordNameHash;
recordNameHash.AppendInt(HashString(aRecordName.get()));
f->Append(recordNameHash);
auto mode = PR_RDWR | PR_CREATE_FILE;
if (aMode == Truncate) {
mode |= PR_TRUNCATE;
}
return f->OpenNSPRFileDesc(mode, PR_IRWXU, aOutFD);
}
nsresult RemoveStorageFile(const nsString& aFilename)
{
nsCOMPtr<nsIFile> f;
nsresult rv = GetGMPStorageDir(getter_AddRefs(f), mGMPName, mNodeId);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
rv = f->Append(aFilename);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
return f->Remove(/* bool recursive= */ false);
}
nsresult OpenStorageFile(const nsAString& aFileLeafName,
const OpenFileMode aMode,
PRFileDesc** aOutFD)
{
MOZ_ASSERT(aOutFD);
nsCOMPtr<nsIFile> f;
nsresult rv = GetGMPStorageDir(getter_AddRefs(f), mGMPName, mNodeId);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
f->Append(aFileLeafName);
auto mode = PR_RDWR | PR_CREATE_FILE;
if (aMode == Truncate) {
mode |= PR_TRUNCATE;
}
return f->OpenNSPRFileDesc(mode, PR_IRWXU, aOutFD);
}
// We store records in a file which is a hash of the record name.
// If there is a hash collision, we just keep adding 1 to the hash
// code, until we find a free slot.
nsresult GetUnusedFilename(const nsACString& aRecordName,
nsString& aOutFilename)
{
nsCOMPtr<nsIFile> storageDir;
nsresult rv = GetGMPStorageDir(getter_AddRefs(storageDir), mGMPName, mNodeId);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
uint64_t recordNameHash = HashString(PromiseFlatCString(aRecordName).get());
for (int i = 0; i < 1000000; i++) {
nsCOMPtr<nsIFile> f;
rv = storageDir->Clone(getter_AddRefs(f));
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
nsAutoString hashStr;
hashStr.AppendInt(recordNameHash);
rv = f->Append(hashStr);
if (NS_WARN_IF(NS_FAILED(rv))) {
return rv;
}
bool exists = false;
f->Exists(&exists);
if (!exists) {
// Filename not in use, we can write into this file.
aOutFilename = hashStr;
return NS_OK;
} else {
// Hash collision; just increment the hash name and try that again.
++recordNameHash;
continue;
}
}
// Somehow, we've managed to completely fail to find a vacant file name.
// Give up.
NS_WARNING("GetUnusedFilename had extreme hash collision!");
return NS_ERROR_FAILURE;
}
nsresult Init() {
// Build our index of records on disk.
nsCOMPtr<nsIFile> storageDir;
nsresult rv = GetGMPStorageDir(getter_AddRefs(storageDir), mGMPName, mNodeId);
if (NS_WARN_IF(NS_FAILED(rv))) {
return NS_ERROR_FAILURE;
}
DirectoryEnumerator iter(storageDir, DirectoryEnumerator::FilesAndDirs);
for (nsCOMPtr<nsIFile> dirEntry; (dirEntry = iter.Next()) != nullptr;) {
PRFileDesc* fd = nullptr;
if (NS_FAILED(dirEntry->OpenNSPRFileDesc(PR_RDONLY, 0, &fd))) {
continue;
}
int32_t recordLength = 0;
nsCString recordName;
nsresult err = ReadRecordMetadata(fd, recordLength, recordName);
PR_Close(fd);
if (NS_FAILED(err)) {
// File is not a valid storage file. Don't index it. Delete the file,
// to make our indexing faster in future.
dirEntry->Remove(false);
continue;
}
nsAutoString filename;
rv = dirEntry->GetLeafName(filename);
if (NS_FAILED(rv)) {
continue;
}
mRecords.Put(recordName, new Record(filename, recordName));
}
return NS_OK;
}
