[nolibc] Change internal syscall API to remove reliance on libc's errno.

This change moves to a model where the error value of a system call is
potentially contained in the return value itself rather than being
implicit in errno.  The helper function internal_iserror can be used
to extract the error value from a return value.  On platforms other
than Linux/x86_64 this still uses errno, but other platforms are free
to port their error handling to this new model.

Differential Revision: http://llvm-reviews.chandlerc.com/D756

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@181436 91177308-0d34-0410-b5e6-96231b3b80d8

3 files changed, 13 insertions, 9 deletions

diff --git a/lib/tsan/rtl/tsan_platform_linux.cc b/lib/tsan/rtl/tsan_platform_linux.cc
index df07ac638..5ccdc49d3 100644
--- a/lib/tsan/rtl/tsan_platform_linux.cc
+++ b/lib/tsan/rtl/tsan_platform_linux.cc
@@ -178,9 +178,10 @@ static void MapRodata() {
   char filename[256];
   internal_snprintf(filename, sizeof(filename), "%s/tsan.rodata.%u",
                     tmpdir, GetPid());
-  fd_t fd = internal_open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
-  if (fd == kInvalidFd)
+  uptr openrv = internal_open(filename, O_RDWR | O_CREAT | O_EXCL, 0600);
+  if (internal_iserror(openrv))
     return;
+  fd_t fd = openrv;
   // Fill the file with kShadowRodata.
   const uptr kMarkerSize = 512 * 1024 / sizeof(u64);
   InternalScopedBuffer<u64> marker(kMarkerSize);
@@ -188,9 +189,9 @@ static void MapRodata() {
     *p = kShadowRodata;
   internal_write(fd, marker.data(), marker.size());
   // Map the file into memory.
-  void *page = internal_mmap(0, kPageSize, PROT_READ | PROT_WRITE,
-                             MAP_PRIVATE | MAP_ANONYMOUS, fd, 0);
-  if (page == MAP_FAILED) {
+  uptr page = internal_mmap(0, kPageSize, PROT_READ | PROT_WRITE,
+                            MAP_PRIVATE | MAP_ANONYMOUS, fd, 0);
+  if (internal_iserror(page)) {
     internal_close(fd);
     internal_unlink(filename);
     return;
diff --git a/lib/tsan/rtl/tsan_rtl.cc b/lib/tsan/rtl/tsan_rtl.cc
index 1205028e3..c51a56690 100644
--- a/lib/tsan/rtl/tsan_rtl.cc
+++ b/lib/tsan/rtl/tsan_rtl.cc
@@ -121,10 +121,12 @@ static void BackgroundThread(void *arg) {
     InternalScopedBuffer<char> filename(4096);
     internal_snprintf(filename.data(), filename.size(), "%s.%d",
         flags()->profile_memory, GetPid());
-    mprof_fd = OpenFile(filename.data(), true);
-    if (mprof_fd == kInvalidFd) {
+    uptr openrv = OpenFile(filename.data(), true);
+    if (internal_iserror(openrv)) {
       Printf("ThreadSanitizer: failed to open memory profile file '%s'\n",
           &filename[0]);
+    } else {
+      mprof_fd = openrv;
     }
   }
 
diff --git a/lib/tsan/rtl/tsan_suppressions.cc b/lib/tsan/rtl/tsan_suppressions.cc
index 47fe7b2d4..14b6a3aca 100644
--- a/lib/tsan/rtl/tsan_suppressions.cc
+++ b/lib/tsan/rtl/tsan_suppressions.cc
@@ -38,12 +38,13 @@ static char *ReadFile(const char *filename) {
     internal_snprintf(tmp.data(), tmp.size(), "%s", filename);
   else
     internal_snprintf(tmp.data(), tmp.size(), "%s/%s", GetPwd(), filename);
-  fd_t fd = OpenFile(tmp.data(), false);
-  if (fd == kInvalidFd) {
+  uptr openrv = OpenFile(tmp.data(), false);
+  if (internal_iserror(openrv)) {
     Printf("ThreadSanitizer: failed to open suppressions file '%s'\n",
                tmp.data());
     Die();
   }
+  fd_t fd = openrv;
   const uptr fsize = internal_filesize(fd);
   if (fsize == (uptr)-1) {
     Printf("ThreadSanitizer: failed to stat suppressions file '%s'\n",