[sanitizer_common] Disable filesystem-related code for Fuchsia

[mcgrathr]

Summary

Fuchsia doesn't support filesystem access per se at low level.
So it won't use any of the filesystem-oriented code in sanitizer_common.

[vitalybuka]

lib/sanitizer_common/sanitizer_suppressions.cc

63 ↗

(On Diff #108729)

if this is not going to support filesystem, why only part of the function is disabled?

[mcgrathr]

lib/sanitizer_common/sanitizer_suppressions.cc

63 ↗

(On Diff #108729)

Fuchsia does not support filesystem-oriented calls per se, but it does implement ReadFileToBuffer in its own way, where the "file name" is treated as an "identifier for configuration text blob" passed to a system service.

[vitalybuka]

LGTM but better to split color and file change

[mcgrathr]

The SupportsColor change here is to avoid using report_file, so I think it belongs in this change.

This is rebased and ready to land after D36028 lands.
Please land it for me!

Thanks,
Roland

[vitalybuka]

lib/sanitizer_common/sanitizer_common_libcdep.cc

38 ↗

(On Diff #109168)

I am going to clang-format this patches.
git clang-format --style file -f origin/master

compiler-rt/trunk/lib/sanitizer_common/sanitizer_common_libcdep.cc

 #include "sanitizer_symbolizer.h"
 
 #if SANITIZER_POSIX
 #include "sanitizer_posix.h"
 #endif
 
 namespace __sanitizer {
 
+#if !SANITIZER_FUCHSIA
+
 bool ReportFile::SupportsColors() {
   SpinMutexLock l(mu);
   ReopenIfNecessary();
   return SupportsColoredOutput(fd);
 }
 
+static INLINE bool ReportSupportsColors() {
+  return report_file.SupportsColors();
+}
+
+#else  // SANITIZER_FUCHSIA
+
+// Fuchsia's logs always go through post-processing that handles colorization.
+static INLINE bool ReportSupportsColors() { return true; }
+
+#endif  // !SANITIZER_FUCHSIA
+
 bool ColorizeReports() {
   // FIXME: Add proper Windows support to AnsiColorDecorator and re-enable color
   // printing on Windows.
   if (SANITIZER_WINDOWS)
     return false;
 
   const char *flag = common_flags()->color;
   return internal_strcmp(flag, "always") == 0 ||
-         (internal_strcmp(flag, "auto") == 0 && report_file.SupportsColors());
+         (internal_strcmp(flag, "auto") == 0 && ReportSupportsColors());
 }
 
 static void (*sandboxing_callback)();
 void SetSandboxingCallback(void (*f)()) {
   sandboxing_callback = f;
 }
 
 void ReportErrorSummary(const char *error_type, const StackTrace *stack,

compiler-rt/trunk/lib/sanitizer_common/sanitizer_file.cc

 //===-- sanitizer_file.cc ------------------------------------------------===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===---------------------------------------------------------------------===//
 //
 // This file is shared between AddressSanitizer and ThreadSanitizer
 // run-time libraries.  It defines filesystem-related interfaces.  This
 // is separate from sanitizer_common.cc so that it's simpler to disable
 // all the filesystem support code for a port that doesn't use it.
 //
 //===---------------------------------------------------------------------===//
 
+#include "sanitizer_platform.h"
+
+#if !SANITIZER_FUCHSIA
+
 #include "sanitizer_common.h"
 #include "sanitizer_file.h"
 
 namespace __sanitizer {
 
 void CatastrophicErrorWrite(const char *buffer, uptr length) {
   WriteToFile(kStderrFd, buffer, length);
 }
void __sanitizer_set_report_path(const char *path) {
   report_file.SetReportPath(path);
 }
 
 void __sanitizer_set_report_fd(void *fd) {
   report_file.fd = (fd_t)reinterpret_cast<uptr>(fd);
   report_file.fd_pid = internal_getpid();
 }
 } // extern "C"
+
+#endif  // !SANITIZER_FUCHSIA

compiler-rt/trunk/lib/sanitizer_common/sanitizer_suppressions.cc

static bool GetPathAssumingFileIsRelativeToExec(const char *file_path,
   }
   return false;
 }
 
 void SuppressionContext::ParseFromFile(const char *filename) {
   if (filename[0] == '\0')
     return;
 
+#if !SANITIZER_FUCHSIA
   // If we cannot find the file, check if its location is relative to
   // the location of the executable.
   InternalScopedString new_file_path(kMaxPathLength);
   if (!FileExists(filename) && !IsAbsolutePath(filename) &&
       GetPathAssumingFileIsRelativeToExec(filename, new_file_path.data(),
                                           new_file_path.size())) {
     filename = new_file_path.data();
   }
+#endif  // !SANITIZER_FUCHSIA
 
   // Read the file.
   VPrintf(1, "%s: reading suppressions file at %s\n",
           SanitizerToolName, filename);
   char *file_contents;
   uptr buffer_size;
   uptr contents_size;
   if (!ReadFileToBuffer(filename, &file_contents, &buffer_size,