py: Implement sys.maxsize, standard way to check platform "bitness".
Implementing it as a static constant is a bit peculiar and require cooperation
from long int implementation.
diff --git a/py/modsys.c b/py/modsys.c
index 1e7f7ef..d215846 100644
--- a/py/modsys.c
+++ b/py/modsys.c
@@ -24,6 +24,8 @@
* THE SOFTWARE.
*/
+#include <stdint.h>
+#include <limits.h>
#include "mpconfig.h"
#include "misc.h"
#include "qstr.h"
@@ -33,6 +35,8 @@
#include "objlist.h"
#include "objtuple.h"
#include "objstr.h"
+#include "mpz.h"
+#include "objint.h"
#if MICROPY_PY_SYS
@@ -44,6 +48,8 @@
extern struct _dummy_t mp_sys_stdout_obj;
extern struct _dummy_t mp_sys_stderr_obj;
+extern mp_obj_int_t mp_maxsize_obj;
+
mp_obj_list_t mp_sys_path_obj;
mp_obj_list_t mp_sys_argv_obj;
#define I(n) MP_OBJ_NEW_SMALL_INT(n)
@@ -70,6 +76,19 @@
#else
{ MP_OBJ_NEW_QSTR(MP_QSTR_byteorder), MP_OBJ_NEW_QSTR(MP_QSTR_big) },
#endif
+#if MICROPY_PY_SYS_MAXSIZE
+ #if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_NONE
+ // INT_MAX is not representable as small int, as we know that small int
+ // takes one bit for tag. So, we have little choice but to provide this
+ // value. Apps also should be careful to not try to compare sys.maxsize
+ // with some number (which may not fit in available int size), but instead
+ // count number of significant bits in sys.maxsize.
+ { MP_OBJ_NEW_QSTR(MP_QSTR_maxsize), MP_OBJ_NEW_SMALL_INT(INT_MAX >> 1) },
+ #else
+ { MP_OBJ_NEW_QSTR(MP_QSTR_maxsize), (mp_obj_t)&mp_maxsize_obj },
+ #endif
+#endif
+
#if MICROPY_PY_SYS_EXIT
{ MP_OBJ_NEW_QSTR(MP_QSTR_exit), (mp_obj_t)&mp_sys_exit_obj },
diff --git a/py/mpconfig.h b/py/mpconfig.h
index da9cffc..c04c69c 100644
--- a/py/mpconfig.h
+++ b/py/mpconfig.h
@@ -336,6 +336,11 @@
#define MICROPY_PY_SYS (1)
#endif
+// Whether to provide "sys.maxsize" constant
+#ifndef MICROPY_PY_SYS_MAXSIZE
+#define MICROPY_PY_SYS_MAXSIZE (0)
+#endif
+
// Whether to provide "sys.exit" function
#ifndef MICROPY_PY_SYS_EXIT
#define MICROPY_PY_SYS_EXIT (0)
diff --git a/py/objint_longlong.c b/py/objint_longlong.c
index 13e3b48..637d9c3 100644
--- a/py/objint_longlong.c
+++ b/py/objint_longlong.c
@@ -50,6 +50,11 @@
#define SUFFIX ""
#endif
+#if MICROPY_PY_SYS_MAXSIZE
+// Export value for sys.maxsize
+const mp_obj_int_t mp_maxsize_obj = {{&mp_type_int}, INT_MAX};
+#endif
+
bool mp_obj_int_is_positive(mp_obj_t self_in) {
if (MP_OBJ_IS_SMALL_INT(self_in)) {
return MP_OBJ_SMALL_INT_VALUE(self_in) >= 0;
diff --git a/py/objint_mpz.c b/py/objint_mpz.c
index da02b1e..6e1c3c5 100644
--- a/py/objint_mpz.c
+++ b/py/objint_mpz.c
@@ -43,6 +43,26 @@
#if MICROPY_LONGINT_IMPL == MICROPY_LONGINT_IMPL_MPZ
+#if MICROPY_PY_SYS_MAXSIZE
+// Export value for sys.maxsize
+#define DIG_MASK ((1 << MPZ_DIG_SIZE) - 1)
+STATIC const mpz_dig_t maxsize_dig[MPZ_NUM_DIG_FOR_INT] = {
+ (INT_MAX >> MPZ_DIG_SIZE * 0) & DIG_MASK,
+ (INT_MAX >> MPZ_DIG_SIZE * 1) & DIG_MASK,
+ (INT_MAX >> MPZ_DIG_SIZE * 2) & DIG_MASK,
+ #if (INT_MAX >> MPZ_DIG_SIZE * 2) > DIG_MASK
+ (INT_MAX >> MPZ_DIG_SIZE * 3) & DIG_MASK,
+ (INT_MAX >> MPZ_DIG_SIZE * 4) & DIG_MASK,
+// (INT_MAX >> MPZ_DIG_SIZE * 5) & DIG_MASK,
+ #endif
+};
+const mp_obj_int_t mp_maxsize_obj = {
+ {&mp_type_int},
+ {.fixed_dig = 1, .len = MPZ_NUM_DIG_FOR_INT, .alloc = MPZ_NUM_DIG_FOR_INT, .dig = (mpz_dig_t*)maxsize_dig}
+};
+#undef DIG_MASK
+#endif
+
STATIC mp_obj_int_t *mp_obj_int_new_mpz(void) {
mp_obj_int_t *o = m_new_obj(mp_obj_int_t);
o->base.type = &mp_type_int;
diff --git a/py/qstrdefs.h b/py/qstrdefs.h
index 4ff9ca8..6fbfabd 100644
--- a/py/qstrdefs.h
+++ b/py/qstrdefs.h
@@ -352,6 +352,9 @@
Q(stderr)
Q(version)
Q(version_info)
+#if MICROPY_PY_SYS_MAXSIZE
+Q(maxsize)
+#endif
#endif
#if MICROPY_PY_STRUCT
diff --git a/unix/mpconfigport.h b/unix/mpconfigport.h
index 002ea79..98132ac 100644
--- a/unix/mpconfigport.h
+++ b/unix/mpconfigport.h
@@ -45,6 +45,7 @@
#define MICROPY_PY_BUILTINS_FROZENSET (1)
#define MICROPY_PY_SYS_EXIT (1)
#define MICROPY_PY_SYS_PLATFORM "linux"
+#define MICROPY_PY_SYS_MAXSIZE (1)
#define MICROPY_PY_SYS_STDFILES (1)
#define MICROPY_PY_CMATH (1)
#define MICROPY_PY_IO_FILEIO (1)