cosmopolitan/third_party/duktape/duk_bi_error.c

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2020-06-15 14:18:57 +00:00
/*
* Error built-ins
*/
#include "third_party/duktape/duk_internal.h"
DUK_INTERNAL duk_ret_t duk_bi_error_constructor_shared(duk_hthread *thr) {
/* Behavior for constructor and non-constructor call is
* the same except for augmenting the created error. When
* called as a constructor, the caller (duk_new()) will handle
* augmentation; when called as normal function, we need to do
* it here.
*/
duk_small_int_t bidx_prototype = duk_get_current_magic(thr);
/* same for both error and each subclass like TypeError */
duk_uint_t flags_and_class = DUK_HOBJECT_FLAG_EXTENSIBLE |
DUK_HOBJECT_FLAG_FASTREFS |
DUK_HOBJECT_CLASS_AS_FLAGS(DUK_HOBJECT_CLASS_ERROR);
(void) duk_push_object_helper(thr, flags_and_class, bidx_prototype);
/* If message is undefined, the own property 'message' is not set at
* all to save property space. An empty message is inherited anyway.
*/
if (!duk_is_undefined(thr, 0)) {
duk_to_string(thr, 0);
duk_dup_0(thr); /* [ message error message ] */
duk_xdef_prop_stridx_short(thr, -2, DUK_STRIDX_MESSAGE, DUK_PROPDESC_FLAGS_WC);
}
/* Augment the error if called as a normal function. __FILE__ and __LINE__
* are not desirable in this case.
*/
#if defined(DUK_USE_AUGMENT_ERROR_CREATE)
if (!duk_is_constructor_call(thr)) {
duk_err_augment_error_create(thr, thr, NULL, 0, DUK_AUGMENT_FLAG_NOBLAME_FILELINE);
}
#endif
return 1;
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_to_string(duk_hthread *thr) {
/* XXX: optimize with more direct internal access */
duk_push_this(thr);
(void) duk_require_hobject_promote_mask(thr, -1, DUK_TYPE_MASK_LIGHTFUNC | DUK_TYPE_MASK_BUFFER);
/* [ ... this ] */
duk_get_prop_stridx_short(thr, -1, DUK_STRIDX_NAME);
if (duk_is_undefined(thr, -1)) {
duk_pop(thr);
duk_push_literal(thr, "Error");
} else {
duk_to_string(thr, -1);
}
/* [ ... this name ] */
/* XXX: Are steps 6 and 7 in E5 Section 15.11.4.4 duplicated by
* accident or are they actually needed? The first ToString()
* could conceivably return 'undefined'.
*/
duk_get_prop_stridx_short(thr, -2, DUK_STRIDX_MESSAGE);
if (duk_is_undefined(thr, -1)) {
duk_pop(thr);
duk_push_hstring_empty(thr);
} else {
duk_to_string(thr, -1);
}
/* [ ... this name message ] */
if (duk_get_length(thr, -2) == 0) {
/* name is empty -> return message */
return 1;
}
if (duk_get_length(thr, -1) == 0) {
/* message is empty -> return name */
duk_pop(thr);
return 1;
}
duk_push_literal(thr, ": ");
duk_insert(thr, -2); /* ... name ': ' message */
duk_concat(thr, 3);
return 1;
}
#if defined(DUK_USE_TRACEBACKS)
/*
* Traceback handling
*
* The unified helper decodes the traceback and produces various requested
* outputs. It should be optimized for size, and may leave garbage on stack,
* only the topmost return value matters. For instance, traceback separator
* and decoded strings are pushed even when looking for filename only.
*
* NOTE: although _Tracedata is an internal property, user code can currently
* write to the array (or replace it with something other than an array).
* The code below must tolerate arbitrary _Tracedata. It can throw errors
* etc, but cannot cause a segfault or memory unsafe behavior.
*/
/* constants arbitrary, chosen for small loads */
#define DUK__OUTPUT_TYPE_TRACEBACK (-1)
#define DUK__OUTPUT_TYPE_FILENAME 0
#define DUK__OUTPUT_TYPE_LINENUMBER 1
DUK_LOCAL duk_ret_t duk__error_getter_helper(duk_hthread *thr, duk_small_int_t output_type) {
duk_idx_t idx_td;
duk_small_int_t i; /* traceback depth fits into 16 bits */
duk_small_int_t t; /* stack type fits into 16 bits */
duk_small_int_t count_func = 0; /* traceback depth ensures fits into 16 bits */
const char *str_tailcall = " tailcall";
const char *str_strict = " strict";
const char *str_construct = " construct";
const char *str_prevyield = " preventsyield";
const char *str_directeval = " directeval";
const char *str_empty = "";
DUK_ASSERT_TOP(thr, 0); /* fixed arg count */
duk_push_this(thr);
duk_xget_owndataprop_stridx_short(thr, -1, DUK_STRIDX_INT_TRACEDATA);
idx_td = duk_get_top_index(thr);
duk_push_hstring_stridx(thr, DUK_STRIDX_NEWLINE_4SPACE);
duk_push_this(thr);
/* [ ... this tracedata sep this ] */
/* XXX: skip null filename? */
if (duk_check_type(thr, idx_td, DUK_TYPE_OBJECT)) {
/* Current tracedata contains 2 entries per callstack entry. */
for (i = 0; ; i += 2) {
duk_int_t pc;
duk_uint_t line;
duk_uint_t flags;
duk_double_t d;
const char *funcname;
const char *filename;
duk_hobject *h_func;
duk_hstring *h_name;
duk_require_stack(thr, 5);
duk_get_prop_index(thr, idx_td, (duk_uarridx_t) i);
duk_get_prop_index(thr, idx_td, (duk_uarridx_t) (i + 1));
d = duk_to_number_m1(thr);
pc = duk_double_to_int_t(DUK_FMOD(d, DUK_DOUBLE_2TO32));
flags = duk_double_to_uint_t(DUK_FLOOR(d / DUK_DOUBLE_2TO32));
t = (duk_small_int_t) duk_get_type(thr, -2);
if (t == DUK_TYPE_OBJECT || t == DUK_TYPE_LIGHTFUNC) {
/*
* ECMAScript/native function call or lightfunc call
*/
count_func++;
/* [ ... v1(func) v2(pc+flags) ] */
/* These may be systematically omitted by Duktape
* with certain config options, but allow user to
* set them on a case-by-case basis.
*/
duk_get_prop_stridx_short(thr, -2, DUK_STRIDX_NAME);
duk_get_prop_stridx_short(thr, -3, DUK_STRIDX_FILE_NAME);
#if defined(DUK_USE_PC2LINE)
line = (duk_uint_t) duk_hobject_pc2line_query(thr, -4, (duk_uint_fast32_t) pc);
#else
line = 0;
#endif
/* [ ... v1 v2 name filename ] */
/* When looking for .fileName/.lineNumber, blame first
* function which has a .fileName.
*/
if (duk_is_string_notsymbol(thr, -1)) {
if (output_type == DUK__OUTPUT_TYPE_FILENAME) {
return 1;
} else if (output_type == DUK__OUTPUT_TYPE_LINENUMBER) {
duk_push_uint(thr, line);
return 1;
}
}
/* XXX: Change 'anon' handling here too, to use empty string for anonymous functions? */
/* XXX: Could be improved by coercing to a readable duk_tval (especially string escaping) */
h_name = duk_get_hstring_notsymbol(thr, -2); /* may be NULL */
funcname = (h_name == NULL || h_name == DUK_HTHREAD_STRING_EMPTY_STRING(thr)) ?
"[anon]" : (const char *) DUK_HSTRING_GET_DATA(h_name);
filename = duk_get_string_notsymbol(thr, -1);
filename = filename ? filename : "";
DUK_ASSERT(funcname != NULL);
DUK_ASSERT(filename != NULL);
h_func = duk_get_hobject(thr, -4); /* NULL for lightfunc */
if (h_func == NULL) {
duk_push_sprintf(thr, "at %s light%s%s%s%s%s",
(const char *) funcname,
(const char *) ((flags & DUK_ACT_FLAG_STRICT) ? str_strict : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_TAILCALLED) ? str_tailcall : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_CONSTRUCT) ? str_construct : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_DIRECT_EVAL) ? str_directeval : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_PREVENT_YIELD) ? str_prevyield : str_empty));
} else if (DUK_HOBJECT_HAS_NATFUNC(h_func)) {
duk_push_sprintf(thr, "at %s (%s) native%s%s%s%s%s",
(const char *) funcname,
(const char *) filename,
(const char *) ((flags & DUK_ACT_FLAG_STRICT) ? str_strict : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_TAILCALLED) ? str_tailcall : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_CONSTRUCT) ? str_construct : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_DIRECT_EVAL) ? str_directeval : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_PREVENT_YIELD) ? str_prevyield : str_empty));
} else {
duk_push_sprintf(thr, "at %s (%s:%lu)%s%s%s%s%s",
(const char *) funcname,
(const char *) filename,
(unsigned long) line,
(const char *) ((flags & DUK_ACT_FLAG_STRICT) ? str_strict : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_TAILCALLED) ? str_tailcall : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_CONSTRUCT) ? str_construct : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_DIRECT_EVAL) ? str_directeval : str_empty),
(const char *) ((flags & DUK_ACT_FLAG_PREVENT_YIELD) ? str_prevyield : str_empty));
}
duk_replace(thr, -5); /* [ ... v1 v2 name filename str ] -> [ ... str v2 name filename ] */
duk_pop_3(thr); /* -> [ ... str ] */
} else if (t == DUK_TYPE_STRING) {
const char *str_file;
/*
* __FILE__ / __LINE__ entry, here 'pc' is line number directly.
* Sometimes __FILE__ / __LINE__ is reported as the source for
* the error (fileName, lineNumber), sometimes not.
*/
/* [ ... v1(filename) v2(line+flags) ] */
/* When looking for .fileName/.lineNumber, blame compilation
* or C call site unless flagged not to do so.
*/
if (!(flags & DUK_TB_FLAG_NOBLAME_FILELINE)) {
if (output_type == DUK__OUTPUT_TYPE_FILENAME) {
duk_pop(thr);
return 1;
} else if (output_type == DUK__OUTPUT_TYPE_LINENUMBER) {
duk_push_int(thr, pc);
return 1;
}
}
/* Tracedata is trusted but avoid any risk of using a NULL
* for %s format because it has undefined behavior. Symbols
* don't need to be explicitly rejected as they pose no memory
* safety issues.
*/
str_file = (const char *) duk_get_string(thr, -2);
duk_push_sprintf(thr, "at [anon] (%s:%ld) internal",
(const char *) (str_file ? str_file : "null"), (long) pc);
duk_replace(thr, -3); /* [ ... v1 v2 str ] -> [ ... str v2 ] */
duk_pop(thr); /* -> [ ... str ] */
} else {
/* unknown, ignore */
duk_pop_2(thr);
break;
}
}
if (count_func >= DUK_USE_TRACEBACK_DEPTH) {
/* Possibly truncated; there is no explicit truncation
* marker so this is the best we can do.
*/
duk_push_hstring_stridx(thr, DUK_STRIDX_BRACKETED_ELLIPSIS);
}
}
/* [ ... this tracedata sep this str1 ... strN ] */
if (output_type != DUK__OUTPUT_TYPE_TRACEBACK) {
return 0;
} else {
/* The 'this' after 'sep' will get ToString() coerced by
* duk_join() automatically. We don't want to do that
* coercion when providing .fileName or .lineNumber (GH-254).
*/
duk_join(thr, duk_get_top(thr) - (idx_td + 2) /*count, not including sep*/);
return 1;
}
}
/* XXX: Output type could be encoded into native function 'magic' value to
* save space. For setters the stridx could be encoded into 'magic'.
*/
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_stack_getter(duk_hthread *thr) {
return duk__error_getter_helper(thr, DUK__OUTPUT_TYPE_TRACEBACK);
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_filename_getter(duk_hthread *thr) {
return duk__error_getter_helper(thr, DUK__OUTPUT_TYPE_FILENAME);
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_linenumber_getter(duk_hthread *thr) {
return duk__error_getter_helper(thr, DUK__OUTPUT_TYPE_LINENUMBER);
}
#else /* DUK_USE_TRACEBACKS */
/*
* Traceback handling when tracebacks disabled.
*
* The fileName / lineNumber stubs are now necessary because built-in
* data will include the accessor properties in Error.prototype. If those
* are removed for builds without tracebacks, these can also be removed.
* 'stack' should still be present and produce a ToString() equivalent:
* this is useful for user code which prints a stacktrace and expects to
* see something useful. A normal stacktrace also begins with a ToString()
* of the error so this makes sense.
*/
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_stack_getter(duk_hthread *thr) {
/* XXX: remove this native function and map 'stack' accessor
* to the toString() implementation directly.
*/
return duk_bi_error_prototype_to_string(thr);
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_filename_getter(duk_hthread *thr) {
DUK_UNREF(thr);
return 0;
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_linenumber_getter(duk_hthread *thr) {
DUK_UNREF(thr);
return 0;
}
#endif /* DUK_USE_TRACEBACKS */
DUK_LOCAL duk_ret_t duk__error_setter_helper(duk_hthread *thr, duk_small_uint_t stridx_key) {
/* Attempt to write 'stack', 'fileName', 'lineNumber' works as if
* user code called Object.defineProperty() to create an overriding
* own property. This allows user code to overwrite .fileName etc
* intuitively as e.g. "err.fileName = 'dummy'" as one might expect.
* See https://github.com/svaarala/duktape/issues/387.
*/
DUK_ASSERT_TOP(thr, 1); /* fixed arg count: value */
duk_push_this(thr);
duk_push_hstring_stridx(thr, stridx_key);
duk_dup_0(thr);
/* [ ... obj key value ] */
DUK_DD(DUK_DDPRINT("error setter: %!T %!T %!T",
duk_get_tval(thr, -3), duk_get_tval(thr, -2), duk_get_tval(thr, -1)));
duk_def_prop(thr, -3, DUK_DEFPROP_HAVE_VALUE |
DUK_DEFPROP_HAVE_WRITABLE | DUK_DEFPROP_WRITABLE |
DUK_DEFPROP_HAVE_ENUMERABLE | /*not enumerable*/
DUK_DEFPROP_HAVE_CONFIGURABLE | DUK_DEFPROP_CONFIGURABLE);
return 0;
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_stack_setter(duk_hthread *thr) {
return duk__error_setter_helper(thr, DUK_STRIDX_STACK);
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_filename_setter(duk_hthread *thr) {
return duk__error_setter_helper(thr, DUK_STRIDX_FILE_NAME);
}
DUK_INTERNAL duk_ret_t duk_bi_error_prototype_linenumber_setter(duk_hthread *thr) {
return duk__error_setter_helper(thr, DUK_STRIDX_LINE_NUMBER);
}