[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

1 files changed, 10 insertions, 8 deletions

diff --git a/lib/sanitizer_common/tests/sanitizer_libc_test.cc b/lib/sanitizer_common/tests/sanitizer_libc_test.cc
index 51cd66cf0..459fa39d5 100644
--- a/lib/sanitizer_common/tests/sanitizer_libc_test.cc
+++ b/lib/sanitizer_common/tests/sanitizer_libc_test.cc
@@ -74,29 +74,31 @@ TEST(SanitizerCommon, FileOps) {
   internal_snprintf(temp_filename, sizeof(temp_filename),
                     "/tmp/sanitizer_common.tmp.%d", uid);
 #endif
-  fd_t fd = OpenFile(temp_filename, true);
-  EXPECT_NE(fd, kInvalidFd);
+  uptr openrv = OpenFile(temp_filename, true);
+  EXPECT_EQ(false, internal_iserror(openrv));
+  fd_t fd = openrv;
   EXPECT_EQ(len1, internal_write(fd, str1, len1));
   EXPECT_EQ(len2, internal_write(fd, str2, len2));
   internal_close(fd);
 
-  fd = OpenFile(temp_filename, false);
-  EXPECT_NE(fd, kInvalidFd);
+  openrv = OpenFile(temp_filename, false);
+  EXPECT_EQ(false, internal_iserror(openrv));
+  fd = openrv;
   uptr fsize = internal_filesize(fd);
   EXPECT_EQ(len1 + len2, fsize);
 
 #if SANITIZER_TEST_HAS_STAT_H
   struct stat st1, st2, st3;
-  EXPECT_EQ(0, internal_stat(temp_filename, &st1));
-  EXPECT_EQ(0, internal_lstat(temp_filename, &st2));
-  EXPECT_EQ(0, internal_fstat(fd, &st3));
+  EXPECT_EQ(0u, internal_stat(temp_filename, &st1));
+  EXPECT_EQ(0u, internal_lstat(temp_filename, &st2));
+  EXPECT_EQ(0u, internal_fstat(fd, &st3));
   EXPECT_EQ(fsize, (uptr)st3.st_size);
 
   // Verify that internal_fstat does not write beyond the end of the supplied
   // buffer.
   struct stat_and_more sam;
   memset(&sam, 0xAB, sizeof(sam));
-  EXPECT_EQ(0, internal_fstat(fd, &sam.st));
+  EXPECT_EQ(0u, internal_fstat(fd, &sam.st));
   EXPECT_EQ(0xAB, sam.z);
   EXPECT_NE(0xAB, sam.st.st_size);
   EXPECT_NE(0, sam.st.st_size);