windows: add SSIZE_MAX Windows doesn't include ssize_t or its _MAX value by default. We are already declaring ssize_t as SSIZE_T, which is __int64_t on Win64 and long otherwise. Include its _MAX value as a correspondence to its type.
diff --git a/src/win32/msvc-compat.h b/src/win32/msvc-compat.h
index ea77820..4cf471f 100644
--- a/src/win32/msvc-compat.h
+++ b/src/win32/msvc-compat.h
@@ -12,6 +12,12 @@
typedef unsigned short mode_t;
typedef SSIZE_T ssize_t;
+#ifdef _WIN64
+# define SSIZE_MAX _I64_MAX
+#else
+# define SSIZE_MAX LONG_MAX
+#endif
+
#define strcasecmp(s1, s2) _stricmp(s1, s2)
#define strncasecmp(s1, s2, c) _strnicmp(s1, s2, c)