clang: Skip attempts to access /proc/self/fd

In contrast to Linux it does not provide entries which can be readlinked
-- these are just regular files, not giving the expected outcome. That's
on top of procfs not being mounted by default to begin with.

Reviewed by:	dim
Differential Revision:		https://reviews.freebsd.org/D34684
This commit is contained in:
Mateusz Guzik 2022-03-27 18:01:38 +00:00
parent ef88adc527
commit 30ed48b0a5

View File

@ -930,7 +930,15 @@ ErrorOr<basic_file_status> directory_entry::status() const {
return s;
}
#if !defined(F_GETPATH)
//
// FreeBSD optionally provides /proc/self/fd, but it is incompatible with
// Linux. The thing to use is realpath.
//
#if !defined(__FreeBSD__)
#define TRY_PROC_SELF_FD
#endif
#if !defined(F_GETPATH) && defined(TRY_PROC_SELF_FD)
static bool hasProcSelfFD() {
// If we have a /proc filesystem mounted, we can quickly establish the
// real name of the file with readlink
@ -1117,6 +1125,7 @@ std::error_code openFileForRead(const Twine &Name, int &ResultFD,
RealPath->append(Buffer, Buffer + strlen(Buffer));
#else
char Buffer[PATH_MAX];
#if defined(TRY_PROC_SELF_FD)
if (hasProcSelfFD()) {
char ProcPath[64];
snprintf(ProcPath, sizeof(ProcPath), "/proc/self/fd/%d", ResultFD);
@ -1124,13 +1133,16 @@ std::error_code openFileForRead(const Twine &Name, int &ResultFD,
if (CharCount > 0)
RealPath->append(Buffer, Buffer + CharCount);
} else {
#endif
SmallString<128> Storage;
StringRef P = Name.toNullTerminatedStringRef(Storage);
// Use ::realpath to get the real path name
if (::realpath(P.begin(), Buffer) != nullptr)
RealPath->append(Buffer, Buffer + strlen(Buffer));
#if defined(TRY_PROC_SELF_FD)
}
#endif
#endif
return std::error_code();
}