Diff: py/objexcept.c

Revision:

0:5868e8752d44

Child:

2:c89e95946844

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/py/objexcept.c	Sat Apr 16 17:11:56 2016 +0000
@@ -0,0 +1,472 @@
+/*
+ * This file is part of the Micro Python project, http://micropython.org/
+ *
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2013, 2014 Damien P. George
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include <string.h>
+#include <stdarg.h>
+#include <assert.h>
+#include <stdio.h>
+
+#include "py/mpstate.h"
+#include "py/objlist.h"
+#include "py/objstr.h"
+#include "py/objtuple.h"
+#include "py/objtype.h"
+#include "py/runtime.h"
+#include "py/gc.h"
+
+// Instance of MemoryError exception - needed by mp_malloc_fail
+const mp_obj_exception_t mp_const_MemoryError_obj = {{&mp_type_MemoryError}, 0, 0, NULL, (mp_obj_tuple_t*)&mp_const_empty_tuple_obj};
+
+// Optionally allocated buffer for storing the first argument of an exception
+// allocated when the heap is locked.
+#if MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF
+#   if MICROPY_EMERGENCY_EXCEPTION_BUF_SIZE > 0
+#define mp_emergency_exception_buf_size MICROPY_EMERGENCY_EXCEPTION_BUF_SIZE
+
+void mp_init_emergency_exception_buf(void) {
+    // Nothing to do since the buffer was declared statically. We put this
+    // definition here so that the calling code can call this function
+    // regardless of how its configured (makes the calling code a bit cleaner).
+}
+
+#else
+#define mp_emergency_exception_buf_size MP_STATE_VM(mp_emergency_exception_buf_size)
+
+void mp_init_emergency_exception_buf(void) {
+    mp_emergency_exception_buf_size = 0;
+    MP_STATE_VM(mp_emergency_exception_buf) = NULL;
+}
+
+mp_obj_t mp_alloc_emergency_exception_buf(mp_obj_t size_in) {
+    mp_int_t size = mp_obj_get_int(size_in);
+    void *buf = NULL;
+    if (size > 0) {
+        buf = m_new(byte, size);
+    }
+
+    int old_size = mp_emergency_exception_buf_size;
+    void *old_buf = MP_STATE_VM(mp_emergency_exception_buf);
+
+    // Update the 2 variables atomically so that an interrupt can't occur
+    // between the assignments.
+    mp_uint_t atomic_state = MICROPY_BEGIN_ATOMIC_SECTION();
+    mp_emergency_exception_buf_size = size;
+    MP_STATE_VM(mp_emergency_exception_buf) = buf;
+    MICROPY_END_ATOMIC_SECTION(atomic_state);
+
+    if (old_buf != NULL) {
+        m_del(byte, old_buf, old_size);
+    }
+    return mp_const_none;
+}
+#endif
+#endif  // MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF
+
+// 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}, 0, 0, NULL, (mp_obj_tuple_t*)&mp_const_empty_tuple_obj};
+
+STATIC void mp_obj_exception_print(const mp_print_t *print, mp_obj_t o_in, mp_print_kind_t kind) {
+    mp_obj_exception_t *o = MP_OBJ_TO_PTR(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)) {
+        mp_print_str(print, qstr_str(o->base.type->name));
+    }
+
+    if (k == PRINT_EXC) {
+        mp_print_str(print, ": ");
+    }
+
+    if (k == PRINT_STR || k == PRINT_EXC) {
+        if (o->args == NULL || o->args->len == 0) {
+            mp_print_str(print, "");
+            return;
+        } else if (o->args->len == 1) {
+            mp_obj_print_helper(print, o->args->items[0], PRINT_STR);
+            return;
+        }
+    }
+    mp_obj_tuple_print(print, MP_OBJ_FROM_PTR(o->args), kind);
+}
+
+mp_obj_t mp_obj_exception_make_new(const mp_obj_type_t *type, size_t n_args, size_t n_kw, const mp_obj_t *args) {
+    mp_arg_check_num(n_args, n_kw, 0, MP_OBJ_FUN_ARGS_MAX, false);
+    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_STATE_VM(mp_emergency_exception_obj);
+        // We can't store any args.
+        o->args = (mp_obj_tuple_t*)&mp_const_empty_tuple_obj;
+    } else {
+        o->args = MP_OBJ_TO_PTR(mp_obj_new_tuple(n_args, args));
+    }
+    o->base.type = type;
+    o->traceback_data = NULL;
+    return MP_OBJ_FROM_PTR(o);
+}
+
+// Get exception "value" - that is, first argument, or None
+mp_obj_t mp_obj_exception_get_value(mp_obj_t self_in) {
+    mp_obj_exception_t *self = MP_OBJ_TO_PTR(self_in);
+    if (self->args->len == 0) {
+        return mp_const_none;
+    } else {
+        return self->args->items[0];
+    }
+}
+
+STATIC void exception_attr(mp_obj_t self_in, qstr attr, mp_obj_t *dest) {
+    if (dest[0] != MP_OBJ_NULL) {
+        // not load attribute
+        return;
+    }
+    mp_obj_exception_t *self = MP_OBJ_TO_PTR(self_in);
+    if (attr == MP_QSTR_args) {
+        dest[0] = MP_OBJ_FROM_PTR(self->args);
+    } else if (self->base.type == &mp_type_StopIteration && attr == MP_QSTR_value) {
+        dest[0] = mp_obj_exception_get_value(self_in);
+    }
+}
+
+STATIC mp_obj_t exc___init__(size_t n_args, const mp_obj_t *args) {
+    mp_obj_exception_t *self = MP_OBJ_TO_PTR(args[0]);
+    mp_obj_t argst = mp_obj_new_tuple(n_args - 1, args + 1);
+    self->args = MP_OBJ_TO_PTR(argst);
+    return mp_const_none;
+}
+STATIC MP_DEFINE_CONST_FUN_OBJ_VAR_BETWEEN(exc___init___obj, 1, MP_OBJ_FUN_ARGS_MAX, exc___init__);
+
+STATIC const mp_rom_map_elem_t exc_locals_dict_table[] = {
+    { MP_ROM_QSTR(MP_QSTR___init__), MP_ROM_PTR(&exc___init___obj) },
+};
+
+STATIC MP_DEFINE_CONST_DICT(exc_locals_dict, exc_locals_dict_table);
+
+const mp_obj_type_t mp_type_BaseException = {
+    { &mp_type_type },
+    .name = MP_QSTR_BaseException,
+    .print = mp_obj_exception_print,
+    .make_new = mp_obj_exception_make_new,
+    .attr = exception_attr,
+    .locals_dict = (mp_obj_dict_t*)&exc_locals_dict,
+};
+
+#define MP_DEFINE_EXCEPTION_BASE(base_name) \
+STATIC const mp_rom_obj_tuple_t mp_type_ ## base_name ## _base_tuple = {{&mp_type_tuple}, 1, {MP_ROM_PTR(&mp_type_ ## base_name)}};\
+
+#define MP_DEFINE_EXCEPTION(exc_name, base_name) \
+const mp_obj_type_t mp_type_ ## exc_name = { \
+    { &mp_type_type }, \
+    .name = MP_QSTR_ ## exc_name, \
+    .print = mp_obj_exception_print, \
+    .make_new = mp_obj_exception_make_new, \
+    .attr = exception_attr, \
+    .bases_tuple = (mp_obj_tuple_t*)(mp_rom_obj_tuple_t*)&mp_type_ ## base_name ## _base_tuple, \
+};
+
+// List of all exceptions, arranged as in the table at:
+// http://docs.python.org/3/library/exceptions.html
+MP_DEFINE_EXCEPTION_BASE(BaseException)
+MP_DEFINE_EXCEPTION(SystemExit, BaseException)
+MP_DEFINE_EXCEPTION(KeyboardInterrupt, BaseException)
+MP_DEFINE_EXCEPTION(GeneratorExit, BaseException)
+MP_DEFINE_EXCEPTION(Exception, BaseException)
+  MP_DEFINE_EXCEPTION_BASE(Exception)
+  MP_DEFINE_EXCEPTION(StopIteration, Exception)
+  MP_DEFINE_EXCEPTION(ArithmeticError, Exception)
+    MP_DEFINE_EXCEPTION_BASE(ArithmeticError)
+    //MP_DEFINE_EXCEPTION(FloatingPointError, ArithmeticError)
+    MP_DEFINE_EXCEPTION(OverflowError, ArithmeticError)
+    MP_DEFINE_EXCEPTION(ZeroDivisionError, ArithmeticError)
+  MP_DEFINE_EXCEPTION(AssertionError, Exception)
+  MP_DEFINE_EXCEPTION(AttributeError, Exception)
+  //MP_DEFINE_EXCEPTION(BufferError, Exception)
+  //MP_DEFINE_EXCEPTION(EnvironmentError, Exception) use OSError instead
+  MP_DEFINE_EXCEPTION(EOFError, Exception)
+  MP_DEFINE_EXCEPTION(ImportError, Exception)
+  //MP_DEFINE_EXCEPTION(IOError, Exception) use OSError instead
+  MP_DEFINE_EXCEPTION(LookupError, Exception)
+    MP_DEFINE_EXCEPTION_BASE(LookupError)
+    MP_DEFINE_EXCEPTION(IndexError, LookupError)
+    MP_DEFINE_EXCEPTION(KeyError, LookupError)
+  MP_DEFINE_EXCEPTION(MemoryError, Exception)
+  MP_DEFINE_EXCEPTION(NameError, Exception)
+    /*
+    MP_DEFINE_EXCEPTION_BASE(NameError)
+    MP_DEFINE_EXCEPTION(UnboundLocalError, NameError)
+    */
+  MP_DEFINE_EXCEPTION(OSError, Exception)
+#if MICROPY_PY_BUILTINS_TIMEOUTERROR
+    MP_DEFINE_EXCEPTION_BASE(OSError)
+    MP_DEFINE_EXCEPTION(TimeoutError, OSError)
+#endif
+    /*
+    MP_DEFINE_EXCEPTION(BlockingIOError, OSError)
+    MP_DEFINE_EXCEPTION(ChildProcessError, OSError)
+    MP_DEFINE_EXCEPTION(ConnectionError, OSError)
+      MP_DEFINE_EXCEPTION(BrokenPipeError, ConnectionError)
+      MP_DEFINE_EXCEPTION(ConnectionAbortedError, ConnectionError)
+      MP_DEFINE_EXCEPTION(ConnectionRefusedError, ConnectionError)
+      MP_DEFINE_EXCEPTION(ConnectionResetError, ConnectionError)
+    MP_DEFINE_EXCEPTION(InterruptedError, OSError)
+    MP_DEFINE_EXCEPTION(IsADirectoryError, OSError)
+    MP_DEFINE_EXCEPTION(NotADirectoryError, OSError)
+    MP_DEFINE_EXCEPTION(PermissionError, OSError)
+    MP_DEFINE_EXCEPTION(ProcessLookupError, OSError)
+    MP_DEFINE_EXCEPTION(FileExistsError, OSError)
+    MP_DEFINE_EXCEPTION(FileNotFoundError, OSError)
+    MP_DEFINE_EXCEPTION(ReferenceError, Exception)
+    */
+  MP_DEFINE_EXCEPTION(RuntimeError, Exception)
+    MP_DEFINE_EXCEPTION_BASE(RuntimeError)
+    MP_DEFINE_EXCEPTION(NotImplementedError, RuntimeError)
+  MP_DEFINE_EXCEPTION(SyntaxError, Exception)
+    MP_DEFINE_EXCEPTION_BASE(SyntaxError)
+    MP_DEFINE_EXCEPTION(IndentationError, SyntaxError)
+    /*
+      MP_DEFINE_EXCEPTION_BASE(IndentationError)
+      MP_DEFINE_EXCEPTION(TabError, IndentationError)
+      */
+  //MP_DEFINE_EXCEPTION(SystemError, Exception)
+  MP_DEFINE_EXCEPTION(TypeError, Exception)
+#if MICROPY_EMIT_NATIVE
+    MP_DEFINE_EXCEPTION_BASE(TypeError)
+    MP_DEFINE_EXCEPTION(ViperTypeError, TypeError)
+#endif
+  MP_DEFINE_EXCEPTION(ValueError, Exception)
+#if MICROPY_PY_BUILTINS_STR_UNICODE
+    MP_DEFINE_EXCEPTION_BASE(ValueError)
+    MP_DEFINE_EXCEPTION(UnicodeError, ValueError)
+    //TODO: Implement more UnicodeError subclasses which take arguments
+#endif
+  /*
+  MP_DEFINE_EXCEPTION(Warning, Exception)
+    MP_DEFINE_EXCEPTION_BASE(Warning)
+    MP_DEFINE_EXCEPTION(DeprecationWarning, Warning)
+    MP_DEFINE_EXCEPTION(PendingDeprecationWarning, Warning)
+    MP_DEFINE_EXCEPTION(RuntimeWarning, Warning)
+    MP_DEFINE_EXCEPTION(SyntaxWarning, Warning)
+    MP_DEFINE_EXCEPTION(UserWarning, Warning)
+    MP_DEFINE_EXCEPTION(FutureWarning, Warning)
+    MP_DEFINE_EXCEPTION(ImportWarning, Warning)
+    MP_DEFINE_EXCEPTION(UnicodeWarning, Warning)
+    MP_DEFINE_EXCEPTION(BytesWarning, Warning)
+    MP_DEFINE_EXCEPTION(ResourceWarning, Warning)
+    */
+
+mp_obj_t mp_obj_new_exception(const mp_obj_type_t *exc_type) {
+    return mp_obj_new_exception_args(exc_type, 0, NULL);
+}
+
+// "Optimized" version for common(?) case of having 1 exception arg
+mp_obj_t mp_obj_new_exception_arg1(const mp_obj_type_t *exc_type, mp_obj_t arg) {
+    return mp_obj_new_exception_args(exc_type, 1, &arg);
+}
+
+mp_obj_t mp_obj_new_exception_args(const mp_obj_type_t *exc_type, mp_uint_t n_args, const mp_obj_t *args) {
+    assert(exc_type->make_new == mp_obj_exception_make_new);
+    return exc_type->make_new(exc_type, n_args, 0, args);
+}
+
+mp_obj_t mp_obj_new_exception_msg(const mp_obj_type_t *exc_type, const char *msg) {
+    return mp_obj_new_exception_msg_varg(exc_type, msg);
+}
+
+mp_obj_t mp_obj_new_exception_msg_varg(const mp_obj_type_t *exc_type, const char *fmt, ...) {
+    // check that the given type is an exception type
+    assert(exc_type->make_new == mp_obj_exception_make_new);
+
+    // make exception object
+    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.
+        // Unfortunately, we won't be able to format the string...
+        o = &MP_STATE_VM(mp_emergency_exception_obj);
+        o->base.type = exc_type;
+        o->traceback_data = NULL;
+        o->args = (mp_obj_tuple_t*)&mp_const_empty_tuple_obj;
+
+#if MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF
+        // If the user has provided a buffer, then we try to create a tuple
+        // of length 1, which has a string object and the string data.
+
+        if (mp_emergency_exception_buf_size > (sizeof(mp_obj_tuple_t) + sizeof(mp_obj_str_t) + sizeof(mp_obj_t))) {
+            mp_obj_tuple_t *tuple = (mp_obj_tuple_t *)MP_STATE_VM(mp_emergency_exception_buf);
+            mp_obj_str_t *str = (mp_obj_str_t *)&tuple->items[1];
+
+            tuple->base.type = &mp_type_tuple;
+            tuple->len = 1;
+            tuple->items[0] = MP_OBJ_FROM_PTR(str);
+
+            byte *str_data = (byte *)&str[1];
+            uint max_len = MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size
+                         - str_data;
+
+            vstr_t vstr;
+            vstr_init_fixed_buf(&vstr, max_len, (char *)str_data);
+
+            va_list ap;
+            va_start(ap, fmt);
+            vstr_vprintf(&vstr, fmt, ap);
+            va_end(ap);
+
+            str->base.type = &mp_type_str;
+            str->hash = qstr_compute_hash(str_data, str->len);
+            str->len = vstr.len;
+            str->data = str_data;
+
+            o->args = tuple;
+
+            uint offset = &str_data[str->len] - MP_STATE_VM(mp_emergency_exception_buf);
+            offset += sizeof(void *) - 1;
+            offset &= ~(sizeof(void *) - 1);
+
+            if ((mp_emergency_exception_buf_size - offset) > (sizeof(o->traceback_data[0]) * 3)) {
+                // We have room to store some traceback.
+                o->traceback_data = (size_t*)((byte *)MP_STATE_VM(mp_emergency_exception_buf) + offset);
+                o->traceback_alloc = (MP_STATE_VM(mp_emergency_exception_buf) + mp_emergency_exception_buf_size - (byte *)o->traceback_data) / sizeof(o->traceback_data[0]);
+                o->traceback_len = 0;
+            }
+        }
+#endif // MICROPY_ENABLE_EMERGENCY_EXCEPTION_BUF
+    } else {
+        o->base.type = exc_type;
+        o->traceback_data = NULL;
+        o->args = MP_OBJ_TO_PTR(mp_obj_new_tuple(1, NULL));
+
+        if (fmt == NULL) {
+            // no message
+            assert(0);
+        } else {
+            if (strchr(fmt, '%') == NULL) {
+                // no formatting substitutions, avoid allocating vstr.
+                o->args->items[0] = mp_obj_new_str(fmt, strlen(fmt), false);
+            } else {
+                // render exception message and store as .args[0]
+                va_list ap;
+                vstr_t vstr;
+                vstr_init(&vstr, 16);
+                va_start(ap, fmt);
+                vstr_vprintf(&vstr, fmt, ap);
+                va_end(ap);
+                o->args->items[0] = mp_obj_new_str_from_vstr(&mp_type_str, &vstr);
+            }
+        }
+    }
+
+    return MP_OBJ_FROM_PTR(o);
+}
+
+// return true if the given object is an exception type
+bool mp_obj_is_exception_type(mp_obj_t self_in) {
+    if (MP_OBJ_IS_TYPE(self_in, &mp_type_type)) {
+        // optimisation when self_in is a builtin exception
+        mp_obj_type_t *self = MP_OBJ_TO_PTR(self_in);
+        if (self->make_new == mp_obj_exception_make_new) {
+            return true;
+        }
+    }
+    return mp_obj_is_subclass_fast(self_in, MP_OBJ_FROM_PTR(&mp_type_BaseException));
+}
+
+// return true if the given object is an instance of an exception type
+bool mp_obj_is_exception_instance(mp_obj_t self_in) {
+    return mp_obj_is_exception_type(MP_OBJ_FROM_PTR(mp_obj_get_type(self_in)));
+}
+
+// Return true if exception (type or instance) is a subclass of given
+// exception type.  Assumes exc_type is a subclass of BaseException, as
+// defined by mp_obj_is_exception_type(exc_type).
+bool mp_obj_exception_match(mp_obj_t exc, mp_const_obj_t exc_type) {
+    // if exc is an instance of an exception, then extract and use its type
+    if (mp_obj_is_exception_instance(exc)) {
+        exc = MP_OBJ_FROM_PTR(mp_obj_get_type(exc));
+    }
+    return mp_obj_is_subclass_fast(exc, exc_type);
+}
+
+// traceback handling functions
+
+#define GET_NATIVE_EXCEPTION(self, self_in) \
+    /* make sure self_in is an exception instance */ \
+    assert(mp_obj_is_exception_instance(self_in)); \
+    mp_obj_exception_t *self; \
+    if (mp_obj_is_native_exception_instance(self_in)) { \
+        self = MP_OBJ_TO_PTR(self_in); \
+    } else { \
+        self = MP_OBJ_TO_PTR(((mp_obj_instance_t*)MP_OBJ_TO_PTR(self_in))->subobj[0]); \
+    }
+
+void mp_obj_exception_clear_traceback(mp_obj_t self_in) {
+    GET_NATIVE_EXCEPTION(self, self_in);
+    // just set the traceback to the null object
+    // we don't want to call any memory management functions here
+    self->traceback_data = NULL;
+}
+
+void mp_obj_exception_add_traceback(mp_obj_t self_in, qstr file, size_t line, qstr block) {
+    GET_NATIVE_EXCEPTION(self, self_in);
+
+    // append this traceback info to traceback data
+    // if memory allocation fails (eg because gc is locked), just return
+
+    if (self->traceback_data == NULL) {
+        self->traceback_data = m_new_maybe(size_t, 3);
+        if (self->traceback_data == NULL) {
+            return;
+        }
+        self->traceback_alloc = 3;
+        self->traceback_len = 0;
+    } else if (self->traceback_len + 3 > self->traceback_alloc) {
+        // be conservative with growing traceback data
+        size_t *tb_data = m_renew_maybe(size_t, self->traceback_data, self->traceback_alloc, self->traceback_alloc + 3, true);
+        if (tb_data == NULL) {
+            return;
+        }
+        self->traceback_data = tb_data;
+        self->traceback_alloc += 3;
+    }
+
+    size_t *tb_data = &self->traceback_data[self->traceback_len];
+    self->traceback_len += 3;
+    tb_data[0] = file;
+    tb_data[1] = line;
+    tb_data[2] = block;
+}
+
+void mp_obj_exception_get_traceback(mp_obj_t self_in, size_t *n, size_t **values) {
+    GET_NATIVE_EXCEPTION(self, self_in);
+
+    if (self->traceback_data == NULL) {
+        *n = 0;
+        *values = NULL;
+    } else {
+        *n = self->traceback_len;
+        *values = self->traceback_data;
+    }
+}