objexcept.c

#include <string.h>
#include <stdarg.h>
#include <assert.h>

#include "nlr.h"
#include "misc.h"
#include "mpconfig.h"
#include "qstr.h"
#include "obj.h"
#include "objtuple.h"
#include "runtime.h"
#include "runtime0.h"

typedef struct _mp_obj_exception_t {
    mp_obj_base_t base;
    mp_obj_t traceback; // a list object, holding (file,line,block) as numbers (not Python objects); a hack for now
    mp_obj_tuple_t *args;
} mp_obj_exception_t;

// Instance of MemoryError exception - needed by mp_malloc_fail
const mp_obj_exception_t mp_const_MemoryError_obj = {{&mp_type_MemoryError}, MP_OBJ_NULL, mp_const_empty_tuple};

// Local non-heap memory for allocating an exception when we run out of RAM
STATIC mp_obj_exception_t mp_emergency_exception_obj;

// Instance of GeneratorExit exception - needed by generator.close()
// This would belong to objgenerator.c, but to keep mp_obj_exception_t
// definition module-private so far, have it here.
const mp_obj_exception_t mp_const_GeneratorExit_obj = {{&mp_type_GeneratorExit}, MP_OBJ_NULL, mp_const_empty_tuple};

STATIC void mp_obj_exception_print(void (*print)(void *env, const char *fmt, ...), void *env, mp_obj_t o_in, mp_print_kind_t kind) {
    mp_obj_exception_t *o = o_in;
    mp_print_kind_t k = kind & ~PRINT_EXC_SUBCLASS;
    bool is_subclass = kind & PRINT_EXC_SUBCLASS;
    if (!is_subclass && (k == PRINT_REPR || k == PRINT_EXC)) {
        print(env, "%s", qstr_str(o->base.type->name));
    }

    if (k == PRINT_EXC) {
        print(env, ": ");
    }

    if (k == PRINT_STR || k == PRINT_EXC) {
        if (o->args == NULL || o->args->len == 0) {
            print(env, "");
            return;
        } else if (o->args->len == 1) {
            mp_obj_print_helper(print, env, o->args->items[0], PRINT_STR);
            return;
        }
    }
    tuple_print(print, env, o->args, kind);
}

mp_obj_t mp_obj_exception_make_new(mp_obj_t type_in, uint n_args, uint n_kw, const mp_obj_t *args) {
    mp_obj_type_t *type = type_in;

    if (n_kw != 0) {
        nlr_raise(mp_obj_new_exception_msg_varg(&mp_type_TypeError, "%s does not take keyword arguments", mp_obj_get_type_str(type_in)));
    }

    mp_obj_exception_t *o = m_new_obj_var_maybe(mp_obj_exception_t, mp_obj_t, 0);
    if (o == NULL) {
        // Couldn't allocate heap memory; use local data instead.
        o = &mp_emergency_exception_obj;
        // We can't store any args.
        n_args = 0;
        o->args = mp_const_empty_tuple;
    } else {
        o->args = mp_obj_new_tuple(n_args, args);