void
ClearNSPRIOInterposing()
{
// If we have already cleared IO interposing, or not initialized it this is
// actually bad.
MOZ_ASSERT(sCloseFn && sReadFn && sWriteFn && sFSyncFn && sFileInfoFn &&
sFileInfo64Fn);
// Get IO methods from NSPR and const cast the structure so we can modify it.
PRIOMethods* methods = const_cast<PRIOMethods*>(PR_GetFileMethods());
// Something is badly wrong if we don't get IO methods... However, we don't
// want to crash over that in non-debug builds. This is unlikely to happen
// so an assert is enough, no need to report it to the caller.
MOZ_ASSERT(methods);
if (!methods) {
return;
}
// Restore original functions
methods->close = sCloseFn;
methods->read = sReadFn;
methods->write = sWriteFn;
methods->fsync = sFSyncFn;
methods->fileInfo = sFileInfoFn;
methods->fileInfo64 = sFileInfo64Fn;
// Forget about original functions
sCloseFn = nullptr;
sReadFn = nullptr;
sWriteFn = nullptr;
sFSyncFn = nullptr;
sFileInfoFn = nullptr;
sFileInfo64Fn = nullptr;
}
void _PR_InitIO(void)
{
const PRIOMethods *methods = PR_GetFileMethods();
_PR_InitFdCache();
_pr_flock_lock = PR_NewLock();
_pr_flock_cv = PR_NewCondVar(_pr_flock_lock);
#ifdef WIN32
_pr_stdin = PR_AllocFileDesc((PROsfd)GetStdHandle(STD_INPUT_HANDLE),
methods);
_pr_stdout = PR_AllocFileDesc((PROsfd)GetStdHandle(STD_OUTPUT_HANDLE),
methods);
_pr_stderr = PR_AllocFileDesc((PROsfd)GetStdHandle(STD_ERROR_HANDLE),
methods);
#ifdef WINNT
_pr_stdin->secret->md.sync_file_io = PR_TRUE;
_pr_stdout->secret->md.sync_file_io = PR_TRUE;
_pr_stderr->secret->md.sync_file_io = PR_TRUE;
#endif
#else
_pr_stdin = PR_AllocFileDesc(0, methods);
_pr_stdout = PR_AllocFileDesc(1, methods);
_pr_stderr = PR_AllocFileDesc(2, methods);
#endif
_PR_MD_INIT_FD_INHERITABLE(_pr_stdin, PR_TRUE);
_PR_MD_INIT_FD_INHERITABLE(_pr_stdout, PR_TRUE);
_PR_MD_INIT_FD_INHERITABLE(_pr_stderr, PR_TRUE);
_PR_MD_INIT_IO();
}
void
InitNSPRIOInterposing()
{
// Check that we have not interposed any of the IO methods before
MOZ_ASSERT(!sCloseFn && !sReadFn && !sWriteFn && !sFSyncFn && !sFileInfoFn &&
!sFileInfo64Fn);
// We can't actually use this assertion because we initialize this code
// before XPCOM is initialized, so NS_IsMainThread() always returns false.
// MOZ_ASSERT(NS_IsMainThread());
// Get IO methods from NSPR and const cast the structure so we can modify it.
PRIOMethods* methods = const_cast<PRIOMethods*>(PR_GetFileMethods());
// Something is badly wrong if we don't get IO methods... However, we don't
// want to crash over that in non-debug builds. This is unlikely to happen
// so an assert is enough, no need to report it to the caller.
MOZ_ASSERT(methods);
if (!methods) {
return;
}
// Store original functions
sCloseFn = methods->close;
sReadFn = methods->read;
sWriteFn = methods->write;
sFSyncFn = methods->fsync;
sFileInfoFn = methods->fileInfo;
sFileInfo64Fn = methods->fileInfo64;
// Overwrite with our interposed functions
methods->close = &interposedClose;
methods->read = &interposedRead;
methods->write = &interposedWrite;
methods->fsync = &interposedFSync;
methods->fileInfo = &interposedFileInfo;
methods->fileInfo64 = &interposedFileInfo64;
}
