Introduce new type for inteceptors UINTMAX_T

[krytarowski]

Summary

The UINTMAX_T type will be used in new interceptors.

While there, correct the type of strtoumax(3) from INTMAX_T to UINTMAX_T.

Original patch from Yang Zheng.

[krytarowski]

ping?

[vitalybuka]

May I ask you to create trivial positive test for this function in sanitizer_common?

[krytarowski]

Do you mean a test for strtoumax(3)?

[vitalybuka]

yes

[krytarowski]

I will prepare a test and submit as a new revision to review.

lib/interception/interception.h

 #endif
 
 // These typedefs should be used only in the interceptor definitions to replace
 // the standard system types (e.g. SSIZE_T instead of ssize_t)
 typedef __sanitizer::uptr    SIZE_T;
 typedef __sanitizer::sptr    SSIZE_T;
 typedef __sanitizer::sptr    PTRDIFF_T;
 typedef __sanitizer::s64     INTMAX_T;
+typedef __sanitizer::u64     UINTMAX_T;
 typedef __sanitizer::OFF_T   OFF_T;
 typedef __sanitizer::OFF64_T OFF64_T;
 
 // How to add an interceptor:
 // Suppose you need to wrap/replace system function (generally, from libc):
 //      int foo(const char *bar, double baz);
 // You'll need to:
 //      1) define INTERCEPTOR(int, foo, const char *bar, double baz) { ... } in

lib/sanitizer_common/sanitizer_common_interceptors.inc

INTERCEPTOR(INTMAX_T, strtoimax, const char *nptr, char **endptr, int base) {
   // its metadata. See
   // https://github.com/google/sanitizers/issues/321.
   char *real_endptr;
   INTMAX_T res = REAL(strtoimax)(nptr, &real_endptr, base);
   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
   return res;
 }
 
-INTERCEPTOR(INTMAX_T, strtoumax, const char *nptr, char **endptr, int base) {
+INTERCEPTOR(UINTMAX_T, strtoumax, const char *nptr, char **endptr, int base) {
   void *ctx;
   COMMON_INTERCEPTOR_ENTER(ctx, strtoumax, nptr, endptr, base);
   // FIXME: under ASan the call below may write to freed memory and corrupt
   // its metadata. See
   // https://github.com/google/sanitizers/issues/321.
   char *real_endptr;
-  INTMAX_T res = REAL(strtoumax)(nptr, &real_endptr, base);
+  UINTMAX_T res = REAL(strtoumax)(nptr, &real_endptr, base);
   StrtolFixAndCheck(ctx, nptr, endptr, real_endptr, base);
   return res;
 }
 
 #define INIT_STRTOIMAX                  \
   COMMON_INTERCEPT_FUNCTION(strtoimax); \
   COMMON_INTERCEPT_FUNCTION(strtoumax);
 #else