1361 lines
41 KiB
C
1361 lines
41 KiB
C
/*
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string_format.h -- implementation of string.format().
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It uses the Objects/stringlib conventions, so that it can be
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compiled for both unicode and string objects.
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*/
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/* Defines for Python 2.6 compatibility */
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#if PY_VERSION_HEX < 0x03000000
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#define PyLong_FromSsize_t _PyLong_FromSsize_t
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#endif
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/* Defines for more efficiently reallocating the string buffer */
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#define INITIAL_SIZE_INCREMENT 100
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#define SIZE_MULTIPLIER 2
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#define MAX_SIZE_INCREMENT 3200
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/************************************************************************/
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/*********** Global data structures and forward declarations *********/
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/************************************************************************/
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/*
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A SubString consists of the characters between two string or
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unicode pointers.
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*/
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typedef struct {
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STRINGLIB_CHAR *ptr;
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STRINGLIB_CHAR *end;
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} SubString;
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typedef enum {
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ANS_INIT,
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ANS_AUTO,
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ANS_MANUAL
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} AutoNumberState; /* Keep track if we're auto-numbering fields */
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/* Keeps track of our auto-numbering state, and which number field we're on */
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typedef struct {
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AutoNumberState an_state;
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int an_field_number;
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} AutoNumber;
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/* forward declaration for recursion */
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static PyObject *
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build_string(SubString *input, PyObject *args, PyObject *kwargs,
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int recursion_depth, AutoNumber *auto_number);
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/************************************************************************/
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/************************** Utility functions ************************/
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/************************************************************************/
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static void
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AutoNumber_Init(AutoNumber *auto_number)
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{
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auto_number->an_state = ANS_INIT;
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auto_number->an_field_number = 0;
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}
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/* fill in a SubString from a pointer and length */
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Py_LOCAL_INLINE(void)
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SubString_init(SubString *str, STRINGLIB_CHAR *p, Py_ssize_t len)
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{
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str->ptr = p;
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if (p == NULL)
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str->end = NULL;
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else
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str->end = str->ptr + len;
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}
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/* return a new string. if str->ptr is NULL, return None */
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Py_LOCAL_INLINE(PyObject *)
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SubString_new_object(SubString *str)
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{
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if (str->ptr == NULL) {
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Py_INCREF(Py_None);
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return Py_None;
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}
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return STRINGLIB_NEW(str->ptr, str->end - str->ptr);
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}
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/* return a new string. if str->ptr is NULL, return None */
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Py_LOCAL_INLINE(PyObject *)
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SubString_new_object_or_empty(SubString *str)
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{
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if (str->ptr == NULL) {
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return STRINGLIB_NEW(NULL, 0);
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}
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return STRINGLIB_NEW(str->ptr, str->end - str->ptr);
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}
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/* Return 1 if an error has been detected switching between automatic
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field numbering and manual field specification, else return 0. Set
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ValueError on error. */
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static int
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autonumber_state_error(AutoNumberState state, int field_name_is_empty)
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{
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if (state == ANS_MANUAL) {
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if (field_name_is_empty) {
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PyErr_SetString(PyExc_ValueError, "cannot switch from "
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"manual field specification to "
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"automatic field numbering");
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return 1;
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}
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}
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else {
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if (!field_name_is_empty) {
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PyErr_SetString(PyExc_ValueError, "cannot switch from "
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"automatic field numbering to "
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"manual field specification");
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return 1;
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}
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}
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return 0;
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}
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/************************************************************************/
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/*********** Output string management functions ****************/
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/************************************************************************/
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typedef struct {
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STRINGLIB_CHAR *ptr;
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STRINGLIB_CHAR *end;
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PyObject *obj;
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Py_ssize_t size_increment;
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} OutputString;
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/* initialize an OutputString object, reserving size characters */
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static int
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output_initialize(OutputString *output, Py_ssize_t size)
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{
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output->obj = STRINGLIB_NEW(NULL, size);
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if (output->obj == NULL)
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return 0;
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output->ptr = STRINGLIB_STR(output->obj);
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output->end = STRINGLIB_LEN(output->obj) + output->ptr;
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output->size_increment = INITIAL_SIZE_INCREMENT;
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return 1;
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}
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/*
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output_extend reallocates the output string buffer.
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It returns a status: 0 for a failed reallocation,
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1 for success.
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*/
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static int
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output_extend(OutputString *output, Py_ssize_t count)
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{
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STRINGLIB_CHAR *startptr = STRINGLIB_STR(output->obj);
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Py_ssize_t curlen = output->ptr - startptr;
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Py_ssize_t maxlen = curlen + count + output->size_increment;
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if (STRINGLIB_RESIZE(&output->obj, maxlen) < 0)
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return 0;
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startptr = STRINGLIB_STR(output->obj);
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output->ptr = startptr + curlen;
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output->end = startptr + maxlen;
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if (output->size_increment < MAX_SIZE_INCREMENT)
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output->size_increment *= SIZE_MULTIPLIER;
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return 1;
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}
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/*
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output_data dumps characters into our output string
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buffer.
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In some cases, it has to reallocate the string.
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It returns a status: 0 for a failed reallocation,
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1 for success.
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*/
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static int
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output_data(OutputString *output, const STRINGLIB_CHAR *s, Py_ssize_t count)
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{
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if ((count > output->end - output->ptr) && !output_extend(output, count))
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return 0;
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memcpy(output->ptr, s, count * sizeof(STRINGLIB_CHAR));
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output->ptr += count;
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return 1;
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}
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/************************************************************************/
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/*********** Format string parsing -- integers and identifiers *********/
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/************************************************************************/
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static Py_ssize_t
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get_integer(const SubString *str)
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{
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Py_ssize_t accumulator = 0;
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Py_ssize_t digitval;
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STRINGLIB_CHAR *p;
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/* empty string is an error */
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if (str->ptr >= str->end)
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return -1;
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for (p = str->ptr; p < str->end; p++) {
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digitval = STRINGLIB_TODECIMAL(*p);
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if (digitval < 0)
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return -1;
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/*
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Detect possible overflow before it happens:
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accumulator * 10 + digitval > PY_SSIZE_T_MAX if and only if
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accumulator > (PY_SSIZE_T_MAX - digitval) / 10.
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*/
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if (accumulator > (PY_SSIZE_T_MAX - digitval) / 10) {
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PyErr_Format(PyExc_ValueError,
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"Too many decimal digits in format string");
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return -1;
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}
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accumulator = accumulator * 10 + digitval;
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}
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return accumulator;
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}
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/************************************************************************/
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/******** Functions to get field objects and specification strings ******/
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/************************************************************************/
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/* do the equivalent of obj.name */
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static PyObject *
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getattr(PyObject *obj, SubString *name)
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{
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PyObject *newobj;
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PyObject *str = SubString_new_object(name);
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if (str == NULL)
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return NULL;
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newobj = PyObject_GetAttr(obj, str);
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Py_DECREF(str);
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return newobj;
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}
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/* do the equivalent of obj[idx], where obj is a sequence */
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static PyObject *
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getitem_sequence(PyObject *obj, Py_ssize_t idx)
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{
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return PySequence_GetItem(obj, idx);
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}
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/* do the equivalent of obj[idx], where obj is not a sequence */
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static PyObject *
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getitem_idx(PyObject *obj, Py_ssize_t idx)
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{
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PyObject *newobj;
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PyObject *idx_obj = PyLong_FromSsize_t(idx);
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if (idx_obj == NULL)
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return NULL;
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newobj = PyObject_GetItem(obj, idx_obj);
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Py_DECREF(idx_obj);
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return newobj;
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}
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/* do the equivalent of obj[name] */
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static PyObject *
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getitem_str(PyObject *obj, SubString *name)
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{
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PyObject *newobj;
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PyObject *str = SubString_new_object(name);
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if (str == NULL)
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return NULL;
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newobj = PyObject_GetItem(obj, str);
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Py_DECREF(str);
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return newobj;
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}
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typedef struct {
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/* the entire string we're parsing. we assume that someone else
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is managing its lifetime, and that it will exist for the
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lifetime of the iterator. can be empty */
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SubString str;
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/* pointer to where we are inside field_name */
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STRINGLIB_CHAR *ptr;
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} FieldNameIterator;
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static int
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FieldNameIterator_init(FieldNameIterator *self, STRINGLIB_CHAR *ptr,
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Py_ssize_t len)
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{
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SubString_init(&self->str, ptr, len);
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self->ptr = self->str.ptr;
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return 1;
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}
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static int
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_FieldNameIterator_attr(FieldNameIterator *self, SubString *name)
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{
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STRINGLIB_CHAR c;
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name->ptr = self->ptr;
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/* return everything until '.' or '[' */
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while (self->ptr < self->str.end) {
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switch (c = *self->ptr++) {
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case '[':
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case '.':
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/* backup so that we this character will be seen next time */
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self->ptr--;
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break;
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default:
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continue;
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}
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break;
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}
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/* end of string is okay */
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name->end = self->ptr;
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return 1;
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}
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static int
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_FieldNameIterator_item(FieldNameIterator *self, SubString *name)
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{
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int bracket_seen = 0;
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STRINGLIB_CHAR c;
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name->ptr = self->ptr;
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|
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/* return everything until ']' */
|
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while (self->ptr < self->str.end) {
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switch (c = *self->ptr++) {
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case ']':
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bracket_seen = 1;
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break;
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default:
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continue;
|
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}
|
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break;
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}
|
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/* make sure we ended with a ']' */
|
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if (!bracket_seen) {
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PyErr_SetString(PyExc_ValueError, "Missing ']' in format string");
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return 0;
|
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}
|
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|
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/* end of string is okay */
|
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/* don't include the ']' */
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name->end = self->ptr-1;
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return 1;
|
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}
|
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|
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/* returns 0 on error, 1 on non-error termination, and 2 if it returns a value */
|
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static int
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FieldNameIterator_next(FieldNameIterator *self, int *is_attribute,
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Py_ssize_t *name_idx, SubString *name)
|
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{
|
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/* check at end of input */
|
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if (self->ptr >= self->str.end)
|
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return 1;
|
|
|
|
switch (*self->ptr++) {
|
|
case '.':
|
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*is_attribute = 1;
|
|
if (_FieldNameIterator_attr(self, name) == 0)
|
|
return 0;
|
|
*name_idx = -1;
|
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break;
|
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case '[':
|
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*is_attribute = 0;
|
|
if (_FieldNameIterator_item(self, name) == 0)
|
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return 0;
|
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*name_idx = get_integer(name);
|
|
if (*name_idx == -1 && PyErr_Occurred())
|
|
return 0;
|
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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;
|
|
}
|