| /* |
| string_format.h -- implementation of string.format(). |
| |
| It uses the Objects/stringlib conventions, so that it can be |
| compiled for both unicode and string objects. |
| */ |
| |
| |
| /* Defines for Python 2.6 compatability */ |
| #if PY_VERSION_HEX < 0x03000000 |
| #define PyLong_FromSsize_t _PyLong_FromSsize_t |
| #endif |
| |
| /* Defines for more efficiently reallocating the string buffer */ |
| #define INITIAL_SIZE_INCREMENT 100 |
| #define SIZE_MULTIPLIER 2 |
| #define MAX_SIZE_INCREMENT 3200 |
| |
| |
| /************************************************************************/ |
| /*********** Global data structures and forward declarations *********/ |
| /************************************************************************/ |
| |
| /* |
| A SubString consists of the characters between two string or |
| unicode pointers. |
| */ |
| typedef struct { |
| STRINGLIB_CHAR *ptr; |
| STRINGLIB_CHAR *end; |
| } SubString; |
| |
| |
| /* forward declaration for recursion */ |
| static PyObject * |
| build_string(SubString *input, PyObject *args, PyObject *kwargs, |
| int recursion_depth); |
| |
| |
| |
| /************************************************************************/ |
| /************************** Utility functions ************************/ |
| /************************************************************************/ |
| |
| /* fill in a SubString from a pointer and length */ |
| Py_LOCAL_INLINE(void) |
| SubString_init(SubString *str, STRINGLIB_CHAR *p, Py_ssize_t len) |
| { |
| str->ptr = p; |
| if (p == NULL) |
| str->end = NULL; |
| else |
| str->end = str->ptr + len; |
| } |
| |
| /* return a new string. if str->ptr is NULL, return None */ |
| Py_LOCAL_INLINE(PyObject *) |
| SubString_new_object(SubString *str) |
| { |
| if (str->ptr == NULL) { |
| Py_INCREF(Py_None); |
| return Py_None; |
| } |
| return STRINGLIB_NEW(str->ptr, str->end - str->ptr); |
| } |
| |
| /* return a new string. if str->ptr is NULL, return None */ |
| Py_LOCAL_INLINE(PyObject *) |
| SubString_new_object_or_empty(SubString *str) |
| { |
| if (str->ptr == NULL) { |
| return STRINGLIB_NEW(NULL, 0); |
| } |
| return STRINGLIB_NEW(str->ptr, str->end - str->ptr); |
| } |
| |
| /************************************************************************/ |
| /*********** Output string management functions ****************/ |
| /************************************************************************/ |
| |
| typedef struct { |
| STRINGLIB_CHAR *ptr; |
| STRINGLIB_CHAR *end; |
| PyObject *obj; |
| Py_ssize_t size_increment; |
| } OutputString; |
| |
| /* initialize an OutputString object, reserving size characters */ |
| static int |
| output_initialize(OutputString *output, Py_ssize_t size) |
| { |
| output->obj = STRINGLIB_NEW(NULL, size); |
| if (output->obj == NULL) |
| return 0; |
| |
| output->ptr = STRINGLIB_STR(output->obj); |
| output->end = STRINGLIB_LEN(output->obj) + output->ptr; |
| output->size_increment = INITIAL_SIZE_INCREMENT; |
| |
| return 1; |
| } |
| |
| /* |
| output_extend reallocates the output string buffer. |
| It returns a status: 0 for a failed reallocation, |
| 1 for success. |
| */ |
| |
| static int |
| output_extend(OutputString *output, Py_ssize_t count) |
| { |
| STRINGLIB_CHAR *startptr = STRINGLIB_STR(output->obj); |
| Py_ssize_t curlen = output->ptr - startptr; |
| Py_ssize_t maxlen = curlen + count + output->size_increment; |
| |
| if (STRINGLIB_RESIZE(&output->obj, maxlen) < 0) |
| return 0; |
| startptr = STRINGLIB_STR(output->obj); |
| output->ptr = startptr + curlen; |
| output->end = startptr + maxlen; |
| if (output->size_increment < MAX_SIZE_INCREMENT) |
| output->size_increment *= SIZE_MULTIPLIER; |
| return 1; |
| } |
| |
| /* |
| output_data dumps characters into our output string |
| buffer. |
| |
| In some cases, it has to reallocate the string. |
| |
| It returns a status: 0 for a failed reallocation, |
| 1 for success. |
| */ |
| static int |
| output_data(OutputString *output, const STRINGLIB_CHAR *s, Py_ssize_t count) |
| { |
| if ((count > output->end - output->ptr) && !output_extend(output, count)) |
| return 0; |
| memcpy(output->ptr, s, count * sizeof(STRINGLIB_CHAR)); |
| output->ptr += count; |
| return 1; |
| } |
| |
| /************************************************************************/ |
| /*********** Format string parsing -- integers and identifiers *********/ |
| /************************************************************************/ |
| |
| static Py_ssize_t |
| get_integer(const SubString *str) |
| { |
| Py_ssize_t accumulator = 0; |
| Py_ssize_t digitval; |
| Py_ssize_t oldaccumulator; |
| STRINGLIB_CHAR *p; |
| |
| /* empty string is an error */ |
| if (str->ptr >= str->end) |
| return -1; |
| |
| for (p = str->ptr; p < str->end; p++) { |
| digitval = STRINGLIB_TODECIMAL(*p); |
| if (digitval < 0) |
| return -1; |
| /* |
| This trick was copied from old Unicode format code. It's cute, |
| but would really suck on an old machine with a slow divide |
| implementation. Fortunately, in the normal case we do not |
| expect too many digits. |
| */ |
| oldaccumulator = accumulator; |
| accumulator *= 10; |
| if ((accumulator+10)/10 != oldaccumulator+1) { |
| PyErr_Format(PyExc_ValueError, |
| "Too many decimal digits in format string"); |
| return -1; |
| } |
| accumulator += digitval; |
| } |
| return accumulator; |
| } |
| |
| /************************************************************************/ |
| /******** Functions to get field objects and specification strings ******/ |
| /************************************************************************/ |
| |
| /* do the equivalent of obj.name */ |
| static PyObject * |
| getattr(PyObject *obj, SubString *name) |
| { |
| PyObject *newobj; |
| PyObject *str = SubString_new_object(name); |
| if (str == NULL) |
| return NULL; |
| newobj = PyObject_GetAttr(obj, str); |
| Py_DECREF(str); |
| return newobj; |
| } |
| |
| /* do the equivalent of obj[idx], where obj is a sequence */ |
| static PyObject * |
| getitem_sequence(PyObject *obj, Py_ssize_t idx) |
| { |
| return PySequence_GetItem(obj, idx); |
| } |
| |
| /* do the equivalent of obj[idx], where obj is not a sequence */ |
| static PyObject * |
| getitem_idx(PyObject *obj, Py_ssize_t idx) |
| { |
| PyObject *newobj; |
| PyObject *idx_obj = PyLong_FromSsize_t(idx); |
| if (idx_obj == NULL) |
| return NULL; |
| newobj = PyObject_GetItem(obj, idx_obj); |
| Py_DECREF(idx_obj); |
| return newobj; |
| } |
| |
| /* do the equivalent of obj[name] */ |
| static PyObject * |
| getitem_str(PyObject *obj, SubString *name) |
| { |
| PyObject *newobj; |
| PyObject *str = SubString_new_object(name); |
| if (str == NULL) |
| return NULL; |
| newobj = PyObject_GetItem(obj, str); |
| Py_DECREF(str); |
| return newobj; |
| } |
| |
| typedef struct { |
| /* the entire string we're parsing. we assume that someone else |
| is managing its lifetime, and that it will exist for the |
| lifetime of the iterator. can be empty */ |
| SubString str; |
| |
| /* pointer to where we are inside field_name */ |
| STRINGLIB_CHAR *ptr; |
| } FieldNameIterator; |
| |
| |
| static int |
| FieldNameIterator_init(FieldNameIterator *self, STRINGLIB_CHAR *ptr, |
| Py_ssize_t len) |
| { |
| SubString_init(&self->str, ptr, len); |
| self->ptr = self->str.ptr; |
| return 1; |
| } |
| |
| static int |
| _FieldNameIterator_attr(FieldNameIterator *self, SubString *name) |
| { |
| STRINGLIB_CHAR c; |
| |
| name->ptr = self->ptr; |
| |
| /* return everything until '.' or '[' */ |
| while (self->ptr < self->str.end) { |
| switch (c = *self->ptr++) { |
| case '[': |
| case '.': |
| /* backup so that we this character will be seen next time */ |
| self->ptr--; |
| break; |
| default: |
| continue; |
| } |
| break; |
| } |
| /* end of string is okay */ |
| name->end = self->ptr; |
| return 1; |
| } |
| |
| static int |
| _FieldNameIterator_item(FieldNameIterator *self, SubString *name) |
| { |
| int bracket_seen = 0; |
| STRINGLIB_CHAR c; |
| |
| name->ptr = self->ptr; |
| |
| /* return everything until ']' */ |
| while (self->ptr < self->str.end) { |
| switch (c = *self->ptr++) { |
| case ']': |
| bracket_seen = 1; |
| break; |
| default: |
| continue; |
| } |
| break; |
| } |
| /* make sure we ended with a ']' */ |
| if (!bracket_seen) { |
| PyErr_SetString(PyExc_ValueError, "Missing ']' in format string"); |
| return 0; |
| } |
| |
| /* end of string is okay */ |
| /* don't include the ']' */ |
| name->end = self->ptr-1; |
| return 1; |
| } |
| |
| /* returns 0 on error, 1 on non-error termination, and 2 if it returns a value */ |
| static int |
| FieldNameIterator_next(FieldNameIterator *self, int *is_attribute, |
| Py_ssize_t *name_idx, SubString *name) |
| { |
| /* check at end of input */ |
| if (self->ptr >= self->str.end) |
| return 1; |
| |
| switch (*self->ptr++) { |
| case '.': |
| *is_attribute = 1; |
| if (_FieldNameIterator_attr(self, name) == 0) |
| return 0; |
| *name_idx = -1; |
| break; |
| case '[': |
| *is_attribute = 0; |
| if (_FieldNameIterator_item(self, name) == 0) |
| return 0; |
| *name_idx = get_integer(name); |
| break; |
| default: |
| /* interal error, can't get here */ |
| assert(0); |
| return 0; |
| } |
| |
| /* empty string is an error */ |
| if (name->ptr == name->end) { |
| PyErr_SetString(PyExc_ValueError, "Empty attribute in format string"); |
| return 0; |
| } |
| |
| return 2; |
| } |
| |
| |
| /* input: field_name |
| output: 'first' points to the part before the first '[' or '.' |
| 'first_idx' is -1 if 'first' is not an integer, otherwise |
| it's the value of first converted to an integer |
| 'rest' is an iterator to return the rest |
| */ |
| static int |
| field_name_split(STRINGLIB_CHAR *ptr, Py_ssize_t len, SubString *first, |
| Py_ssize_t *first_idx, FieldNameIterator *rest) |
| { |
| STRINGLIB_CHAR c; |
| STRINGLIB_CHAR *p = ptr; |
| STRINGLIB_CHAR *end = ptr + len; |
| |
| /* find the part up until the first '.' or '[' */ |
| while (p < end) { |
| switch (c = *p++) { |
| case '[': |
| case '.': |
| /* backup so that we this character is available to the |
| "rest" iterator */ |
| p--; |
| break; |
| default: |
| continue; |
| } |
| break; |
| } |
| |
| /* set up the return values */ |
| SubString_init(first, ptr, p - ptr); |
| FieldNameIterator_init(rest, p, end - p); |
| |
| /* see if "first" is an integer, in which case it's used as an index */ |
| *first_idx = get_integer(first); |
| |
| /* zero length string is an error */ |
| if (first->ptr >= first->end) { |
| PyErr_SetString(PyExc_ValueError, "empty field name"); |
| goto error; |
| } |
| |
| return 1; |
| error: |
| return 0; |
| } |
| |
| |
| /* |
| get_field_object returns the object inside {}, before the |
| format_spec. It handles getindex and getattr lookups and consumes |
| the entire input string. |
| */ |
| static PyObject * |
| get_field_object(SubString *input, PyObject *args, PyObject *kwargs) |
| { |
| PyObject *obj = NULL; |
| int ok; |
| int is_attribute; |
| SubString name; |
| SubString first; |
| Py_ssize_t index; |
| FieldNameIterator rest; |
| |
| if (!field_name_split(input->ptr, input->end - input->ptr, &first, |
| &index, &rest)) { |
| goto error; |
| } |
| |
| if (index == -1) { |
| /* look up in kwargs */ |
| PyObject *key = SubString_new_object(&first); |
| if (key == NULL) |
| goto error; |
| if ((kwargs == NULL) || (obj = PyDict_GetItem(kwargs, key)) == NULL) { |
| PyErr_SetObject(PyExc_KeyError, key); |
| Py_DECREF(key); |
| goto error; |
| } |
| Py_DECREF(key); |
| Py_INCREF(obj); |
| } |
| else { |
| /* look up in args */ |
| obj = PySequence_GetItem(args, index); |
| if (obj == NULL) |
| goto error; |
| } |
| |
| /* iterate over the rest of the field_name */ |
| while ((ok = FieldNameIterator_next(&rest, &is_attribute, &index, |
| &name)) == 2) { |
| PyObject *tmp; |
| |
| if (is_attribute) |
| /* getattr lookup "." */ |
| tmp = getattr(obj, &name); |
| else |
| /* getitem lookup "[]" */ |
| if (index == -1) |
| tmp = getitem_str(obj, &name); |
| else |
| if (PySequence_Check(obj)) |
| tmp = getitem_sequence(obj, index); |
| else |
| /* not a sequence */ |
| tmp = getitem_idx(obj, index); |
| if (tmp == NULL) |
| goto error; |
| |
| /* assign to obj */ |
| Py_DECREF(obj); |
| obj = tmp; |
| } |
| /* end of iterator, this is the non-error case */ |
| if (ok == 1) |
| return obj; |
| error: |
| Py_XDECREF(obj); |
| return NULL; |
| } |
| |
| /************************************************************************/ |
| /***************** Field rendering functions **************************/ |
| /************************************************************************/ |
| |
| /* |
| render_field() is the main function in this section. It takes the |
| field object and field specification string generated by |
| get_field_and_spec, and renders the field into the output string. |
| |
| render_field calls fieldobj.__format__(format_spec) method, and |
| appends to the output. |
| */ |
| static int |
| render_field(PyObject *fieldobj, SubString *format_spec, OutputString *output) |
| { |
| int ok = 0; |
| PyObject *result = NULL; |
| PyObject *format_spec_object = NULL; |
| PyObject *(*formatter)(PyObject *, STRINGLIB_CHAR *, Py_ssize_t) = NULL; |
| STRINGLIB_CHAR* format_spec_start = format_spec->ptr ? |
| format_spec->ptr : NULL; |
| Py_ssize_t format_spec_len = format_spec->ptr ? |
| format_spec->end - format_spec->ptr : 0; |
| |
| /* If we know the type exactly, skip the lookup of __format__ and just |
| call the formatter directly. */ |
| if (PyUnicode_CheckExact(fieldobj)) |
| formatter = _PyUnicode_FormatAdvanced; |
| else if (PyLong_CheckExact(fieldobj)) |
| formatter =_PyLong_FormatAdvanced; |
| else if (PyFloat_CheckExact(fieldobj)) |
| formatter = _PyFloat_FormatAdvanced; |
| |
| /* XXX: for 2.6, convert format_spec to the appropriate type |
| (unicode, str) */ |
| |
| if (formatter) { |
| /* we know exactly which formatter will be called when __format__ is |
| looked up, so call it directly, instead. */ |
| result = formatter(fieldobj, format_spec_start, format_spec_len); |
| } |
| else { |
| /* We need to create an object out of the pointers we have, because |
| __format__ takes a string/unicode object for format_spec. */ |
| format_spec_object = STRINGLIB_NEW(format_spec_start, |
| format_spec_len); |
| if (format_spec_object == NULL) |
| goto done; |
| |
| result = PyObject_Format(fieldobj, format_spec_object); |
| } |
| if (result == NULL) |
| goto done; |
| |
| #if PY_VERSION_HEX >= 0x03000000 |
| assert(PyUnicode_Check(result)); |
| #else |
| assert(PyBytes_Check(result) || PyUnicode_Check(result)); |
| |
| /* Convert result to our type. We could be str, and result could |
| be unicode */ |
| { |
| PyObject *tmp = STRINGLIB_TOSTR(result); |
| if (tmp == NULL) |
| goto done; |
| Py_DECREF(result); |
| result = tmp; |
| } |
| #endif |
| |
| ok = output_data(output, |
| STRINGLIB_STR(result), STRINGLIB_LEN(result)); |
| done: |
| Py_XDECREF(format_spec_object); |
| Py_XDECREF(result); |
| return ok; |
| } |
| |
| static int |
| parse_field(SubString *str, SubString *field_name, SubString *format_spec, |
| STRINGLIB_CHAR *conversion) |
| { |
| STRINGLIB_CHAR c = 0; |
| |
| /* initialize these, as they may be empty */ |
| *conversion = '\0'; |
| SubString_init(format_spec, NULL, 0); |
| |
| /* search for the field name. it's terminated by the end of the |
| string, or a ':' or '!' */ |
| field_name->ptr = str->ptr; |
| while (str->ptr < str->end) { |
| switch (c = *(str->ptr++)) { |
| case ':': |
| case '!': |
| break; |
| default: |
| continue; |
| } |
| break; |
| } |
| |
| if (c == '!' || c == ':') { |
| /* we have a format specifier and/or a conversion */ |
| /* don't include the last character */ |
| field_name->end = str->ptr-1; |
| |
| /* the format specifier is the rest of the string */ |
| format_spec->ptr = str->ptr; |
| format_spec->end = str->end; |
| |
| /* see if there's a conversion specifier */ |
| if (c == '!') { |
| /* there must be another character present */ |
| if (format_spec->ptr >= format_spec->end) { |
| PyErr_SetString(PyExc_ValueError, |
| "end of format while looking for conversion " |
| "specifier"); |
| return 0; |
| } |
| *conversion = *(format_spec->ptr++); |
| |
| /* if there is another character, it must be a colon */ |
| if (format_spec->ptr < format_spec->end) { |
| c = *(format_spec->ptr++); |
| if (c != ':') { |
| PyErr_SetString(PyExc_ValueError, |
| "expected ':' after format specifier"); |
| return 0; |
| } |
| } |
| } |
| |
| return 1; |
| |
| } |
| else { |
| /* end of string, there's no format_spec or conversion */ |
| field_name->end = str->ptr; |
| return 1; |
| } |
| } |
| |
| /************************************************************************/ |
| /******* Output string allocation and escape-to-markup processing ******/ |
| /************************************************************************/ |
| |
| /* MarkupIterator breaks the string into pieces of either literal |
| text, or things inside {} that need to be marked up. it is |
| designed to make it easy to wrap a Python iterator around it, for |
| use with the Formatter class */ |
| |
| typedef struct { |
| SubString str; |
| } MarkupIterator; |
| |
| static int |
| MarkupIterator_init(MarkupIterator *self, STRINGLIB_CHAR *ptr, Py_ssize_t len) |
| { |
| SubString_init(&self->str, ptr, len); |
| return 1; |
| } |
| |
| /* returns 0 on error, 1 on non-error termination, and 2 if it got a |
| string (or something to be expanded) */ |
| static int |
| MarkupIterator_next(MarkupIterator *self, SubString *literal, |
| SubString *field_name, SubString *format_spec, |
| STRINGLIB_CHAR *conversion, |
| int *format_spec_needs_expanding) |
| { |
| int at_end; |
| STRINGLIB_CHAR c = 0; |
| STRINGLIB_CHAR *start; |
| int count; |
| Py_ssize_t len; |
| int markup_follows = 0; |
| |
| /* initialize all of the output variables */ |
| SubString_init(literal, NULL, 0); |
| SubString_init(field_name, NULL, 0); |
| SubString_init(format_spec, NULL, 0); |
| *conversion = '\0'; |
| *format_spec_needs_expanding = 0; |
| |
| /* No more input, end of iterator. This is the normal exit |
| path. */ |
| if (self->str.ptr >= self->str.end) |
| return 1; |
| |
| start = self->str.ptr; |
| |
| /* First read any literal text. Read until the end of string, an |
| escaped '{' or '}', or an unescaped '{'. In order to never |
| allocate memory and so I can just pass pointers around, if |
| there's an escaped '{' or '}' then we'll return the literal |
| including the brace, but no format object. The next time |
| through, we'll return the rest of the literal, skipping past |
| the second consecutive brace. */ |
| while (self->str.ptr < self->str.end) { |
| switch (c = *(self->str.ptr++)) { |
| case '{': |
| case '}': |
| markup_follows = 1; |
| break; |
| default: |
| continue; |
| } |
| break; |
| } |
| |
| at_end = self->str.ptr >= self->str.end; |
| len = self->str.ptr - start; |
| |
| if ((c == '}') && (at_end || (c != *self->str.ptr))) { |
| PyErr_SetString(PyExc_ValueError, "Single '}' encountered " |
| "in format string"); |
| return 0; |
| } |
| if (at_end && c == '{') { |
| PyErr_SetString(PyExc_ValueError, "Single '{' encountered " |
| "in format string"); |
| return 0; |
| } |
| if (!at_end) { |
| if (c == *self->str.ptr) { |
| /* escaped } or {, skip it in the input. there is no |
| markup object following us, just this literal text */ |
| self->str.ptr++; |
| markup_follows = 0; |
| } |
| else |
| len--; |
| } |
| |
| /* record the literal text */ |
| literal->ptr = start; |
| literal->end = start + len; |
| |
| if (!markup_follows) |
| return 2; |
| |
| /* this is markup, find the end of the string by counting nested |
| braces. note that this prohibits escaped braces, so that |
| format_specs cannot have braces in them. */ |
| count = 1; |
| |
| start = self->str.ptr; |
| |
| /* we know we can't have a zero length string, so don't worry |
| about that case */ |
| while (self->str.ptr < self->str.end) { |
| switch (c = *(self->str.ptr++)) { |
| case '{': |
| /* the format spec needs to be recursively expanded. |
| this is an optimization, and not strictly needed */ |
| *format_spec_needs_expanding = 1; |
| count++; |
| break; |
| case '}': |
| count--; |
| if (count <= 0) { |
| /* we're done. parse and get out */ |
| SubString s; |
| |
| SubString_init(&s, start, self->str.ptr - 1 - start); |
| if (parse_field(&s, field_name, format_spec, conversion) == 0) |
| return 0; |
| |
| /* a zero length field_name is an error */ |
| if (field_name->ptr == field_name->end) { |
| PyErr_SetString(PyExc_ValueError, "zero length field name " |
| "in format"); |
| return 0; |
| } |
| |
| /* success */ |
| return 2; |
| } |
| break; |
| } |
| } |
| |
| /* end of string while searching for matching '}' */ |
| PyErr_SetString(PyExc_ValueError, "unmatched '{' in format"); |
| return 0; |
| } |
| |
| |
| /* do the !r or !s conversion on obj */ |
| static PyObject * |
| do_conversion(PyObject *obj, STRINGLIB_CHAR conversion) |
| { |
| /* XXX in pre-3.0, do we need to convert this to unicode, since it |
| might have returned a string? */ |
| switch (conversion) { |
| case 'r': |
| return PyObject_Repr(obj); |
| case 's': |
| return STRINGLIB_TOSTR(obj); |
| default: |
| if (conversion > 32 && conversion < 127) { |
| /* It's the ASCII subrange; casting to char is safe |
| (assuming the execution character set is an ASCII |
| superset). */ |
| PyErr_Format(PyExc_ValueError, |
| "Unknown conversion specifier %c", |
| (char)conversion); |
| } else |
| PyErr_Format(PyExc_ValueError, |
| "Unknown conversion specifier \\x%x", |
| (unsigned int)conversion); |
| return NULL; |
| } |
| } |
| |
| /* given: |
| |
| {field_name!conversion:format_spec} |
| |
| compute the result and write it to output. |
| format_spec_needs_expanding is an optimization. if it's false, |
| just output the string directly, otherwise recursively expand the |
| format_spec string. */ |
| |
| static int |
| output_markup(SubString *field_name, SubString *format_spec, |
| int format_spec_needs_expanding, STRINGLIB_CHAR conversion, |
| OutputString *output, PyObject *args, PyObject *kwargs, |
| int recursion_depth) |
| { |
| PyObject *tmp = NULL; |
| PyObject *fieldobj = NULL; |
| SubString expanded_format_spec; |
| SubString *actual_format_spec; |
| int result = 0; |
| |
| /* convert field_name to an object */ |
| fieldobj = get_field_object(field_name, args, kwargs); |
| if (fieldobj == NULL) |
| goto done; |
| |
| if (conversion != '\0') { |
| tmp = do_conversion(fieldobj, conversion); |
| if (tmp == NULL) |
| goto done; |
| |
| /* do the assignment, transferring ownership: fieldobj = tmp */ |
| Py_DECREF(fieldobj); |
| fieldobj = tmp; |
| tmp = NULL; |
| } |
| |
| /* if needed, recurively compute the format_spec */ |
| if (format_spec_needs_expanding) { |
| tmp = build_string(format_spec, args, kwargs, recursion_depth-1); |
| if (tmp == NULL) |
| goto done; |
| |
| /* note that in the case we're expanding the format string, |
| tmp must be kept around until after the call to |
| render_field. */ |
| SubString_init(&expanded_format_spec, |
| STRINGLIB_STR(tmp), STRINGLIB_LEN(tmp)); |
| actual_format_spec = &expanded_format_spec; |
| } |
| else |
| actual_format_spec = format_spec; |
| |
| if (render_field(fieldobj, actual_format_spec, output) == 0) |
| goto done; |
| |
| result = 1; |
| |
| done: |
| Py_XDECREF(fieldobj); |
| Py_XDECREF(tmp); |
| |
| return result; |
| } |
| |
| /* |
| do_markup is the top-level loop for the format() method. It |
| searches through the format string for escapes to markup codes, and |
| calls other functions to move non-markup text to the output, |
| and to perform the markup to the output. |
| */ |
| static int |
| do_markup(SubString *input, PyObject *args, PyObject *kwargs, |
| OutputString *output, int recursion_depth) |
| { |
| MarkupIterator iter; |
| int format_spec_needs_expanding; |
| int result; |
| SubString literal; |
| SubString field_name; |
| SubString format_spec; |
| STRINGLIB_CHAR conversion; |
| |
| MarkupIterator_init(&iter, input->ptr, input->end - input->ptr); |
| while ((result = MarkupIterator_next(&iter, &literal, &field_name, |
| &format_spec, &conversion, |
| &format_spec_needs_expanding)) == 2) { |
| if (!output_data(output, literal.ptr, literal.end - literal.ptr)) |
| return 0; |
| if (field_name.ptr != field_name.end) |
| if (!output_markup(&field_name, &format_spec, |
| format_spec_needs_expanding, conversion, output, |
| args, kwargs, recursion_depth)) |
| return 0; |
| } |
| return result; |
| } |
| |
| |
| /* |
| build_string allocates the output string and then |
| calls do_markup to do the heavy lifting. |
| */ |
| static PyObject * |
| build_string(SubString *input, PyObject *args, PyObject *kwargs, |
| int recursion_depth) |
| { |
| OutputString output; |
| PyObject *result = NULL; |
| Py_ssize_t count; |
| |
| output.obj = NULL; /* needed so cleanup code always works */ |
| |
| /* check the recursion level */ |
| if (recursion_depth <= 0) { |
| PyErr_SetString(PyExc_ValueError, |
| "Max string recursion exceeded"); |
| goto done; |
| } |
| |
| /* initial size is the length of the format string, plus the size |
| increment. seems like a reasonable default */ |
| if (!output_initialize(&output, |
| input->end - input->ptr + |
| INITIAL_SIZE_INCREMENT)) |
| goto done; |
| |
| if (!do_markup(input, args, kwargs, &output, recursion_depth)) { |
| goto done; |
| } |
| |
| count = output.ptr - STRINGLIB_STR(output.obj); |
| if (STRINGLIB_RESIZE(&output.obj, count) < 0) { |
| goto done; |
| } |
| |
| /* transfer ownership to result */ |
| result = output.obj; |
| output.obj = NULL; |
| |
| done: |
| Py_XDECREF(output.obj); |
| return result; |
| } |
| |
| /************************************************************************/ |
| /*********** main routine ***********************************************/ |
| /************************************************************************/ |
| |
| /* this is the main entry point */ |
| static PyObject * |
| do_string_format(PyObject *self, PyObject *args, PyObject *kwargs) |
| { |
| SubString input; |
| |
| /* PEP 3101 says only 2 levels, so that |
| "{0:{1}}".format('abc', 's') # works |
| "{0:{1:{2}}}".format('abc', 's', '') # fails |
| */ |
| int recursion_depth = 2; |
| |
| SubString_init(&input, STRINGLIB_STR(self), STRINGLIB_LEN(self)); |
| return build_string(&input, args, kwargs, recursion_depth); |
| } |
| |
| |
| |
| /************************************************************************/ |
| /*********** formatteriterator ******************************************/ |
| /************************************************************************/ |
| |
| /* This is used to implement string.Formatter.vparse(). It exists so |
| Formatter can share code with the built in unicode.format() method. |
| It's really just a wrapper around MarkupIterator that is callable |
| from Python. */ |
| |
| typedef struct { |
| PyObject_HEAD |
| |
| STRINGLIB_OBJECT *str; |
| |
| MarkupIterator it_markup; |
| } formatteriterobject; |
| |
| static void |
| formatteriter_dealloc(formatteriterobject *it) |
| { |
| Py_XDECREF(it->str); |
| PyObject_FREE(it); |
| } |
| |
| /* returns a tuple: |
| (literal, field_name, format_spec, conversion) |
| |
| literal is any literal text to output. might be zero length |
| field_name is the string before the ':'. might be None |
| format_spec is the string after the ':'. mibht be None |
| conversion is either None, or the string after the '!' |
| */ |
| static PyObject * |
| formatteriter_next(formatteriterobject *it) |
| { |
| SubString literal; |
| SubString field_name; |
| SubString format_spec; |
| STRINGLIB_CHAR conversion; |
| int format_spec_needs_expanding; |
| int result = MarkupIterator_next(&it->it_markup, &literal, &field_name, |
| &format_spec, &conversion, |
| &format_spec_needs_expanding); |
| |
| /* all of the SubString objects point into it->str, so no |
| memory management needs to be done on them */ |
| assert(0 <= result && result <= 2); |
| if (result == 0 || result == 1) |
| /* if 0, error has already been set, if 1, iterator is empty */ |
| return NULL; |
| else { |
| PyObject *literal_str = NULL; |
| PyObject *field_name_str = NULL; |
| PyObject *format_spec_str = NULL; |
| PyObject *conversion_str = NULL; |
| PyObject *tuple = NULL; |
| int has_field = field_name.ptr != field_name.end; |
| |
| literal_str = SubString_new_object(&literal); |
| if (literal_str == NULL) |
| goto done; |
| |
| field_name_str = SubString_new_object(&field_name); |
| if (field_name_str == NULL) |
| goto done; |
| |
| /* if field_name is non-zero length, return a string for |
| format_spec (even if zero length), else return None */ |
| format_spec_str = (has_field ? |
| SubString_new_object_or_empty : |
| SubString_new_object)(&format_spec); |
| if (format_spec_str == NULL) |
| goto done; |
| |
| /* if the conversion is not specified, return a None, |
| otherwise create a one length string with the conversion |
| character */ |
| if (conversion == '\0') { |
| conversion_str = Py_None; |
| Py_INCREF(conversion_str); |
| } |
| else |
| conversion_str = STRINGLIB_NEW(&conversion, 1); |
| if (conversion_str == NULL) |
| goto done; |
| |
| tuple = PyTuple_Pack(4, literal_str, field_name_str, format_spec_str, |
| conversion_str); |
| done: |
| Py_XDECREF(literal_str); |
| Py_XDECREF(field_name_str); |
| Py_XDECREF(format_spec_str); |
| Py_XDECREF(conversion_str); |
| return tuple; |
| } |
| } |
| |
| static PyMethodDef formatteriter_methods[] = { |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| static PyTypeObject PyFormatterIter_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "formatteriterator", /* tp_name */ |
| sizeof(formatteriterobject), /* tp_basicsize */ |
| 0, /* tp_itemsize */ |
| /* methods */ |
| (destructor)formatteriter_dealloc, /* tp_dealloc */ |
| 0, /* tp_print */ |
| 0, /* tp_getattr */ |
| 0, /* tp_setattr */ |
| 0, /* tp_compare */ |
| 0, /* tp_repr */ |
| 0, /* tp_as_number */ |
| 0, /* tp_as_sequence */ |
| 0, /* tp_as_mapping */ |
| 0, /* tp_hash */ |
| 0, /* tp_call */ |
| 0, /* tp_str */ |
| PyObject_GenericGetAttr, /* tp_getattro */ |
| 0, /* tp_setattro */ |
| 0, /* tp_as_buffer */ |
| Py_TPFLAGS_DEFAULT, /* tp_flags */ |
| 0, /* tp_doc */ |
| 0, /* tp_traverse */ |
| 0, /* tp_clear */ |
| 0, /* tp_richcompare */ |
| 0, /* tp_weaklistoffset */ |
| PyObject_SelfIter, /* tp_iter */ |
| (iternextfunc)formatteriter_next, /* tp_iternext */ |
| formatteriter_methods, /* tp_methods */ |
| 0, |
| }; |
| |
| /* unicode_formatter_parser is used to implement |
| string.Formatter.vformat. it parses a string and returns tuples |
| describing the parsed elements. It's a wrapper around |
| stringlib/string_format.h's MarkupIterator */ |
| static PyObject * |
| formatter_parser(STRINGLIB_OBJECT *self) |
| { |
| formatteriterobject *it; |
| |
| it = PyObject_New(formatteriterobject, &PyFormatterIter_Type); |
| if (it == NULL) |
| return NULL; |
| |
| /* take ownership, give the object to the iterator */ |
| Py_INCREF(self); |
| it->str = self; |
| |
| /* initialize the contained MarkupIterator */ |
| MarkupIterator_init(&it->it_markup, |
| STRINGLIB_STR(self), |
| STRINGLIB_LEN(self)); |
| |
| return (PyObject *)it; |
| } |
| |
| |
| /************************************************************************/ |
| /*********** fieldnameiterator ******************************************/ |
| /************************************************************************/ |
| |
| |
| /* This is used to implement string.Formatter.vparse(). It parses the |
| field name into attribute and item values. It's a Python-callable |
| wrapper around FieldNameIterator */ |
| |
| typedef struct { |
| PyObject_HEAD |
| |
| STRINGLIB_OBJECT *str; |
| |
| FieldNameIterator it_field; |
| } fieldnameiterobject; |
| |
| static void |
| fieldnameiter_dealloc(fieldnameiterobject *it) |
| { |
| Py_XDECREF(it->str); |
| PyObject_FREE(it); |
| } |
| |
| /* returns a tuple: |
| (is_attr, value) |
| is_attr is true if we used attribute syntax (e.g., '.foo') |
| false if we used index syntax (e.g., '[foo]') |
| value is an integer or string |
| */ |
| static PyObject * |
| fieldnameiter_next(fieldnameiterobject *it) |
| { |
| int result; |
| int is_attr; |
| Py_ssize_t idx; |
| SubString name; |
| |
| result = FieldNameIterator_next(&it->it_field, &is_attr, |
| &idx, &name); |
| if (result == 0 || result == 1) |
| /* if 0, error has already been set, if 1, iterator is empty */ |
| return NULL; |
| else { |
| PyObject* result = NULL; |
| PyObject* is_attr_obj = NULL; |
| PyObject* obj = NULL; |
| |
| is_attr_obj = PyBool_FromLong(is_attr); |
| if (is_attr_obj == NULL) |
| goto done; |
| |
| /* either an integer or a string */ |
| if (idx != -1) |
| obj = PyLong_FromSsize_t(idx); |
| else |
| obj = SubString_new_object(&name); |
| if (obj == NULL) |
| goto done; |
| |
| /* return a tuple of values */ |
| result = PyTuple_Pack(2, is_attr_obj, obj); |
| |
| done: |
| Py_XDECREF(is_attr_obj); |
| Py_XDECREF(obj); |
| return result; |
| } |
| } |
| |
| static PyMethodDef fieldnameiter_methods[] = { |
| {NULL, NULL} /* sentinel */ |
| }; |
| |
| static PyTypeObject PyFieldNameIter_Type = { |
| PyVarObject_HEAD_INIT(&PyType_Type, 0) |
| "fieldnameiterator", /* tp_name */ |
| sizeof(fieldnameiterobject), /* tp_basicsize */ |
| 0, /* tp_itemsize */ |
| /* methods */ |
| (destructor)fieldnameiter_dealloc, /* tp_dealloc */ |
| 0, /* tp_print */ |
| 0, /* tp_getattr */ |
| 0, /* tp_setattr */ |
| 0, /* tp_compare */ |
| 0, /* tp_repr */ |
| 0, /* tp_as_number */ |
| 0, /* tp_as_sequence */ |
| 0, /* tp_as_mapping */ |
| 0, /* tp_hash */ |
| 0, /* tp_call */ |
| 0, /* tp_str */ |
| PyObject_GenericGetAttr, /* tp_getattro */ |
| 0, /* tp_setattro */ |
| 0, /* tp_as_buffer */ |
| Py_TPFLAGS_DEFAULT, /* tp_flags */ |
| 0, /* tp_doc */ |
| 0, /* tp_traverse */ |
| 0, /* tp_clear */ |
| 0, /* tp_richcompare */ |
| 0, /* tp_weaklistoffset */ |
| PyObject_SelfIter, /* tp_iter */ |
| (iternextfunc)fieldnameiter_next, /* tp_iternext */ |
| fieldnameiter_methods, /* tp_methods */ |
| 0}; |
| |
| /* unicode_formatter_field_name_split is used to implement |
| string.Formatter.vformat. it takes an PEP 3101 "field name", and |
| returns a tuple of (first, rest): "first", the part before the |
| first '.' or '['; and "rest", an iterator for the rest of the field |
| name. it's a wrapper around stringlib/string_format.h's |
| field_name_split. The iterator it returns is a |
| FieldNameIterator */ |
| static PyObject * |
| formatter_field_name_split(STRINGLIB_OBJECT *self) |
| { |
| SubString first; |
| Py_ssize_t first_idx; |
| fieldnameiterobject *it; |
| |
| PyObject *first_obj = NULL; |
| PyObject *result = NULL; |
| |
| it = PyObject_New(fieldnameiterobject, &PyFieldNameIter_Type); |
| if (it == NULL) |
| return NULL; |
| |
| /* take ownership, give the object to the iterator. this is |
| just to keep the field_name alive */ |
| Py_INCREF(self); |
| it->str = self; |
| |
| if (!field_name_split(STRINGLIB_STR(self), |
| STRINGLIB_LEN(self), |
| &first, &first_idx, &it->it_field)) |
| goto done; |
| |
| /* first becomes an integer, if possible; else a string */ |
| if (first_idx != -1) |
| first_obj = PyLong_FromSsize_t(first_idx); |
| else |
| /* convert "first" into a string object */ |
| first_obj = SubString_new_object(&first); |
| if (first_obj == NULL) |
| goto done; |
| |
| /* return a tuple of values */ |
| result = PyTuple_Pack(2, first_obj, it); |
| |
| done: |
| Py_XDECREF(it); |
| Py_XDECREF(first_obj); |
| return result; |
| } |