| /* | |
| 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 compatibility */ | |
| #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; | |
| typedef enum { | |
| ANS_INIT, | |
| ANS_AUTO, | |
| ANS_MANUAL | |
| } AutoNumberState; /* Keep track if we're auto-numbering fields */ | |
| /* Keeps track of our auto-numbering state, and which number field we're on */ | |
| typedef struct { | |
| AutoNumberState an_state; | |
| int an_field_number; | |
| } AutoNumber; | |
| /* forward declaration for recursion */ | |
| static PyObject * | |
| build_string(SubString *input, PyObject *args, PyObject *kwargs, | |
| int recursion_depth, AutoNumber *auto_number); | |
| /************************************************************************/ | |
| /************************** Utility functions ************************/ | |
| /************************************************************************/ | |
| static void | |
| AutoNumber_Init(AutoNumber *auto_number) | |
| { | |
| auto_number->an_state = ANS_INIT; | |
| auto_number->an_field_number = 0; | |
| } | |
| /* 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); | |
| } | |
| /* Return 1 if an error has been detected switching between automatic | |
| field numbering and manual field specification, else return 0. Set | |
| ValueError on error. */ | |
| static int | |
| autonumber_state_error(AutoNumberState state, int field_name_is_empty) | |
| { | |
| if (state == ANS_MANUAL) { | |
| if (field_name_is_empty) { | |
| PyErr_SetString(PyExc_ValueError, "cannot switch from " | |
| "manual field specification to " | |
| "automatic field numbering"); | |
| return 1; | |
| } | |
| } | |
| else { | |
| if (!field_name_is_empty) { | |
| PyErr_SetString(PyExc_ValueError, "cannot switch from " | |
| "automatic field numbering to " | |
| "manual field specification"); | |
| return 1; | |
| } | |
| } | |
| return 0; | |
| } | |
| /************************************************************************/ | |
| /*********** 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); | |
| if (*name_idx == -1 && PyErr_Occurred()) | |
| return 0; | |
| break; | |
| default: | |
| /* Invalid character follows ']' */ | |
| PyErr_SetString(PyExc_ValueError, "Only '.' or '[' may " | |
| "follow ']' in format field specifier"); | |
| 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, | |
| AutoNumber *auto_number) | |
| { | |
| STRINGLIB_CHAR c; | |
| STRINGLIB_CHAR *p = ptr; | |
| STRINGLIB_CHAR *end = ptr + len; | |
| int field_name_is_empty; | |
| int using_numeric_index; | |
| /* 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); | |
| if (*first_idx == -1 && PyErr_Occurred()) | |
| return 0; | |
| field_name_is_empty = first->ptr >= first->end; | |
| /* If the field name is omitted or if we have a numeric index | |
| specified, then we're doing numeric indexing into args. */ | |
| using_numeric_index = field_name_is_empty || *first_idx != -1; | |
| /* We always get here exactly one time for each field we're | |
| processing. And we get here in field order (counting by left | |
| braces). So this is the perfect place to handle automatic field | |
| numbering if the field name is omitted. */ | |
| /* Check if we need to do the auto-numbering. It's not needed if | |
| we're called from string.Format routines, because it's handled | |
| in that class by itself. */ | |
| if (auto_number) { | |
| /* Initialize our auto numbering state if this is the first | |
| time we're either auto-numbering or manually numbering. */ | |
| if (auto_number->an_state == ANS_INIT && using_numeric_index) | |
| auto_number->an_state = field_name_is_empty ? | |
| ANS_AUTO : ANS_MANUAL; | |
| /* Make sure our state is consistent with what we're doing | |
| this time through. Only check if we're using a numeric | |
| index. */ | |
| if (using_numeric_index) | |
| if (autonumber_state_error(auto_number->an_state, | |
| field_name_is_empty)) | |
| return 0; | |
| /* Zero length field means we want to do auto-numbering of the | |
| fields. */ | |
| if (field_name_is_empty) | |
| *first_idx = (auto_number->an_field_number)++; | |
| } | |
| return 1; | |
| } | |
| /* | |
| 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, | |
| AutoNumber *auto_number) | |
| { | |
| 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, auto_number)) { | |
| 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 STRINGLIB_IS_UNICODE | |
| if (PyUnicode_CheckExact(fieldobj)) | |
| formatter = _PyUnicode_FormatAdvanced; | |
| /* Unfortunately, there's a problem with checking for int, long, | |
| and float here. If we're being included as unicode, their | |
| formatters expect string format_spec args. For now, just skip | |
| this optimization for unicode. This could be fixed, but it's a | |
| hassle. */ | |
| #else | |
| if (PyString_CheckExact(fieldobj)) | |
| formatter = _PyBytes_FormatAdvanced; | |
| else if (PyInt_CheckExact(fieldobj)) | |
| formatter =_PyInt_FormatAdvanced; | |
| else if (PyLong_CheckExact(fieldobj)) | |
| formatter =_PyLong_FormatAdvanced; | |
| else if (PyFloat_CheckExact(fieldobj)) | |
| formatter = _PyFloat_FormatAdvanced; | |
| #endif | |
| 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(PyString_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) | |
| { | |
| /* Note this function works if the field name is zero length, | |
| which is good. Zero length field names are handled later, in | |
| field_name_split. */ | |
| 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; | |
| } | |
| } | |
| } | |
| } | |
| 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, | |
| int *field_present, 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; | |
| *field_present = 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. */ | |
| *field_present = 1; | |
| 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; | |
| /* 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. | |
| field_name is allowed to be zero length, in which case we | |
| are doing auto field numbering. | |
| */ | |
| 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, AutoNumber *auto_number) | |
| { | |
| 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, auto_number); | |
| 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, | |
| auto_number); | |
| 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, AutoNumber *auto_number) | |
| { | |
| MarkupIterator iter; | |
| int format_spec_needs_expanding; | |
| int result; | |
| int field_present; | |
| 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_present, | |
| &field_name, &format_spec, | |
| &conversion, | |
| &format_spec_needs_expanding)) == 2) { | |
| if (!output_data(output, literal.ptr, literal.end - literal.ptr)) | |
| return 0; | |
| if (field_present) | |
| if (!output_markup(&field_name, &format_spec, | |
| format_spec_needs_expanding, conversion, output, | |
| args, kwargs, recursion_depth, auto_number)) | |
| 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, AutoNumber *auto_number) | |
| { | |
| 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, | |
| auto_number)) { | |
| 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; | |
| AutoNumber auto_number; | |
| AutoNumber_Init(&auto_number); | |
| SubString_init(&input, STRINGLIB_STR(self), STRINGLIB_LEN(self)); | |
| return build_string(&input, args, kwargs, recursion_depth, &auto_number); | |
| } | |
| /************************************************************************/ | |
| /*********** 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 field_present; | |
| int result = MarkupIterator_next(&it->it_markup, &literal, &field_present, | |
| &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; | |
| 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 = (field_present ? | |
| 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; | |
| /* Pass in auto_number = NULL. We'll return an empty string for | |
| first_obj in that case. */ | |
| if (!field_name_split(STRINGLIB_STR(self), | |
| STRINGLIB_LEN(self), | |
| &first, &first_idx, &it->it_field, NULL)) | |
| 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; | |
| } |