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			975 lines
		
	
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			975 lines
		
	
	
	
		
			28 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /* implements the string, long, and float formatters.  that is,
 | |
|    string.__format__, etc. */
 | |
| 
 | |
| /* Before including this, you must include either:
 | |
|    stringlib/unicodedefs.h
 | |
|    stringlib/stringdefs.h
 | |
| 
 | |
|    Also, you should define the names:
 | |
|    FORMAT_STRING
 | |
|    FORMAT_LONG
 | |
|    FORMAT_FLOAT
 | |
|    to be whatever you want the public names of these functions to
 | |
|    be.  These are the only non-static functions defined here.
 | |
| */
 | |
| 
 | |
| /*
 | |
|     get_integer consumes 0 or more decimal digit characters from an
 | |
|     input string, updates *result with the corresponding positive
 | |
|     integer, and returns the number of digits consumed.
 | |
| 
 | |
|     returns -1 on error.
 | |
| */
 | |
| static int
 | |
| get_integer(STRINGLIB_CHAR **ptr, STRINGLIB_CHAR *end,
 | |
|                   Py_ssize_t *result)
 | |
| {
 | |
|     Py_ssize_t accumulator, digitval, oldaccumulator;
 | |
|     int numdigits;
 | |
|     accumulator = numdigits = 0;
 | |
|     for (;;(*ptr)++, numdigits++) {
 | |
|         if (*ptr >= end)
 | |
|             break;
 | |
|         digitval = STRINGLIB_TODECIMAL(**ptr);
 | |
|         if (digitval < 0)
 | |
|             break;
 | |
|         /*
 | |
|            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;
 | |
|     }
 | |
|     *result = accumulator;
 | |
|     return numdigits;
 | |
| }
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** standard format specifier parsing **************************/
 | |
| /************************************************************************/
 | |
| 
 | |
| /* returns true if this character is a specifier alignment token */
 | |
| Py_LOCAL_INLINE(int)
 | |
| is_alignment_token(STRINGLIB_CHAR c)
 | |
| {
 | |
|     switch (c) {
 | |
|     case '<': case '>': case '=': case '^':
 | |
|         return 1;
 | |
|     default:
 | |
|         return 0;
 | |
|     }
 | |
| }
 | |
| 
 | |
| /* returns true if this character is a sign element */
 | |
| Py_LOCAL_INLINE(int)
 | |
| is_sign_element(STRINGLIB_CHAR c)
 | |
| {
 | |
|     switch (c) {
 | |
|     case ' ': case '+': case '-': case '(':
 | |
|         return 1;
 | |
|     default:
 | |
|         return 0;
 | |
|     }
 | |
| }
 | |
| 
 | |
| 
 | |
| typedef struct {
 | |
|     STRINGLIB_CHAR fill_char;
 | |
|     STRINGLIB_CHAR align;
 | |
|     STRINGLIB_CHAR sign;
 | |
|     Py_ssize_t width;
 | |
|     Py_ssize_t precision;
 | |
|     STRINGLIB_CHAR type;
 | |
| } InternalFormatSpec;
 | |
| 
 | |
| /*
 | |
|   ptr points to the start of the format_spec, end points just past its end.
 | |
|   fills in format with the parsed information.
 | |
|   returns 1 on success, 0 on failure.
 | |
|   if failure, sets the exception
 | |
| */
 | |
| static int
 | |
| parse_internal_render_format_spec(PyObject *format_spec,
 | |
|                                   InternalFormatSpec *format,
 | |
|                                   char default_type)
 | |
| {
 | |
|     STRINGLIB_CHAR *ptr = STRINGLIB_STR(format_spec);
 | |
|     STRINGLIB_CHAR *end = ptr + STRINGLIB_LEN(format_spec);
 | |
| 
 | |
|     /* end-ptr is used throughout this code to specify the length of
 | |
|        the input string */
 | |
| 
 | |
|     Py_ssize_t specified_width;
 | |
| 
 | |
|     format->fill_char = '\0';
 | |
|     format->align = '\0';
 | |
|     format->sign = '\0';
 | |
|     format->width = -1;
 | |
|     format->precision = -1;
 | |
|     format->type = default_type;
 | |
| 
 | |
|     /* If the second char is an alignment token,
 | |
|        then parse the fill char */
 | |
|     if (end-ptr >= 2 && is_alignment_token(ptr[1])) {
 | |
|         format->align = ptr[1];
 | |
|         format->fill_char = ptr[0];
 | |
|         ptr += 2;
 | |
|     }
 | |
|     else if (end-ptr >= 1 && is_alignment_token(ptr[0])) {
 | |
|         format->align = ptr[0];
 | |
|         ptr++;
 | |
|     }
 | |
| 
 | |
|     /* Parse the various sign options */
 | |
|     if (end-ptr >= 1 && is_sign_element(ptr[0])) {
 | |
|         format->sign = ptr[0];
 | |
|         ptr++;
 | |
|         if (end-ptr >= 1 && ptr[0] == ')') {
 | |
|             ptr++;
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /* The special case for 0-padding (backwards compat) */
 | |
|     if (format->fill_char == '\0' &&
 | |
|             end-ptr >= 1 && ptr[0] == '0') {
 | |
|         format->fill_char = '0';
 | |
|         if (format->align == '\0') {
 | |
|             format->align = '=';
 | |
|         }
 | |
|         ptr++;
 | |
|     }
 | |
| 
 | |
|     /* XXX add error checking */
 | |
|     specified_width = get_integer(&ptr, end, &format->width);
 | |
| 
 | |
|     /* if specified_width is 0, we didn't consume any characters for
 | |
|        the width. in that case, reset the width to -1, because
 | |
|        get_integer() will have set it to zero */
 | |
|     if (specified_width == 0) {
 | |
|         format->width = -1;
 | |
|     }
 | |
| 
 | |
|     /* Parse field precision */
 | |
|     if (end-ptr && ptr[0] == '.') {
 | |
|         ptr++;
 | |
| 
 | |
|         /* XXX add error checking */
 | |
|         specified_width = get_integer(&ptr, end, &format->precision);
 | |
| 
 | |
|         /* not having a precision after a dot is an error */
 | |
|         if (specified_width == 0) {
 | |
|             PyErr_Format(PyExc_ValueError,
 | |
|                          "Format specifier missing precision");
 | |
|             return 0;
 | |
|         }
 | |
| 
 | |
|     }
 | |
| 
 | |
|     /* Finally, parse the type field */
 | |
| 
 | |
|     if (end-ptr > 1) {
 | |
|         /* invalid conversion spec */
 | |
|         PyErr_Format(PyExc_ValueError, "Invalid conversion specification");
 | |
|         return 0;
 | |
|     }
 | |
| 
 | |
|     if (end-ptr == 1) {
 | |
|         format->type = ptr[0];
 | |
|         ptr++;
 | |
|     }
 | |
| 
 | |
|     return 1;
 | |
| }
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** common routines for numeric formatting *********************/
 | |
| /************************************************************************/
 | |
| 
 | |
| /* describes the layout for an integer, see the comment in
 | |
|    _calc_integer_widths() for details */
 | |
| typedef struct {
 | |
|     Py_ssize_t n_lpadding;
 | |
|     Py_ssize_t n_spadding;
 | |
|     Py_ssize_t n_rpadding;
 | |
|     char lsign;
 | |
|     Py_ssize_t n_lsign;
 | |
|     char rsign;
 | |
|     Py_ssize_t n_rsign;
 | |
|     Py_ssize_t n_total; /* just a convenience, it's derivable from the
 | |
|                            other fields */
 | |
| } NumberFieldWidths;
 | |
| 
 | |
| /* not all fields of format are used.  for example, precision is
 | |
|    unused.  should this take discrete params in order to be more clear
 | |
|    about what it does?  or is passing a single format parameter easier
 | |
|    and more efficient enough to justify a little obfuscation? */
 | |
| static void
 | |
| calc_number_widths(NumberFieldWidths *r, STRINGLIB_CHAR actual_sign,
 | |
|                    Py_ssize_t n_digits, const InternalFormatSpec *format)
 | |
| {
 | |
|     r->n_lpadding = 0;
 | |
|     r->n_spadding = 0;
 | |
|     r->n_rpadding = 0;
 | |
|     r->lsign = '\0';
 | |
|     r->n_lsign = 0;
 | |
|     r->rsign = '\0';
 | |
|     r->n_rsign = 0;
 | |
| 
 | |
|     /* the output will look like:
 | |
|        |                                                           |
 | |
|        | <lpadding> <lsign> <spadding> <digits> <rsign> <rpadding> |
 | |
|        |                                                           |
 | |
| 
 | |
|        lsign and rsign are computed from format->sign and the actual
 | |
|        sign of the number
 | |
| 
 | |
|        digits is already known
 | |
| 
 | |
|        the total width is either given, or computed from the
 | |
|        actual digits
 | |
| 
 | |
|        only one of lpadding, spadding, and rpadding can be non-zero,
 | |
|        and it's calculated from the width and other fields
 | |
|     */
 | |
| 
 | |
|     /* compute the various parts we're going to write */
 | |
|     if (format->sign == '+') {
 | |
|         /* always put a + or - */
 | |
|         r->n_lsign = 1;
 | |
|         r->lsign = (actual_sign == '-' ? '-' : '+');
 | |
|     }
 | |
|     else if (format->sign == '(') {
 | |
|         if (actual_sign == '-') {
 | |
|             r->n_lsign = 1;
 | |
|             r->lsign = '(';
 | |
|             r->n_rsign = 1;
 | |
|             r->rsign = ')';
 | |
|         }
 | |
|     }
 | |
|     else if (format->sign == ' ') {
 | |
|         r->n_lsign = 1;
 | |
|         r->lsign = (actual_sign == '-' ? '-' : ' ');
 | |
|     }
 | |
|     else {
 | |
|         /* non specified, or the default (-) */
 | |
|         if (actual_sign == '-') {
 | |
|             r->n_lsign = 1;
 | |
|             r->lsign = '-';
 | |
|         }
 | |
|     }
 | |
| 
 | |
|     /* now the number of padding characters */
 | |
|     if (format->width == -1) {
 | |
|         /* no padding at all, nothing to do */
 | |
|     }
 | |
|     else {
 | |
|         /* see if any padding is needed */
 | |
|         if (r->n_lsign + n_digits + r->n_rsign >= format->width) {
 | |
|             /* no padding needed, we're already bigger than the
 | |
|                requested width */
 | |
|         }
 | |
|         else {
 | |
|             /* determine which of left, space, or right padding is
 | |
|                needed */
 | |
|             Py_ssize_t padding = format->width - (r->n_lsign + n_digits + r->n_rsign);
 | |
|             if (format->align == '<')
 | |
|                 r->n_rpadding = padding;
 | |
|             else if (format->align == '>')
 | |
|                 r->n_lpadding = padding;
 | |
|             else if (format->align == '^') {
 | |
|                 r->n_lpadding = padding / 2;
 | |
|                 r->n_rpadding = padding - r->n_lpadding;
 | |
|             }
 | |
|             else
 | |
|                 /* must be '=' */
 | |
|                 r->n_spadding = padding;
 | |
|         }
 | |
|     }
 | |
|     r->n_total = r->n_lpadding + r->n_lsign + r->n_spadding +
 | |
|         n_digits + r->n_rsign + r->n_rpadding;
 | |
| }
 | |
| 
 | |
| /* fill in the non-digit parts of a numbers's string representation,
 | |
|    as determined in _calc_integer_widths().  returns the pointer to
 | |
|    where the digits go. */
 | |
| static STRINGLIB_CHAR *
 | |
| fill_number(STRINGLIB_CHAR *p_buf, const NumberFieldWidths *spec,
 | |
|             Py_ssize_t n_digits, STRINGLIB_CHAR fill_char)
 | |
| {
 | |
|     STRINGLIB_CHAR* p_digits;
 | |
| 
 | |
|     if (spec->n_lpadding) {
 | |
|         STRINGLIB_FILL(p_buf, fill_char, spec->n_lpadding);
 | |
|         p_buf += spec->n_lpadding;
 | |
|     }
 | |
|     if (spec->n_lsign == 1) {
 | |
|         *p_buf++ = spec->lsign;
 | |
|     }
 | |
|     if (spec->n_spadding) {
 | |
|         STRINGLIB_FILL(p_buf, fill_char, spec->n_spadding);
 | |
|         p_buf += spec->n_spadding;
 | |
|     }
 | |
|     p_digits = p_buf;
 | |
|     p_buf += n_digits;
 | |
|     if (spec->n_rsign == 1) {
 | |
|         *p_buf++ = spec->rsign;
 | |
|     }
 | |
|     if (spec->n_rpadding) {
 | |
|         STRINGLIB_FILL(p_buf, fill_char, spec->n_rpadding);
 | |
|         p_buf += spec->n_rpadding;
 | |
|     }
 | |
|     return p_digits;
 | |
| }
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** string formatting ******************************************/
 | |
| /************************************************************************/
 | |
| 
 | |
| static PyObject *
 | |
| format_string_internal(PyObject *value, const InternalFormatSpec *format)
 | |
| {
 | |
|     Py_ssize_t width; /* total field width */
 | |
|     Py_ssize_t lpad;
 | |
|     STRINGLIB_CHAR *dst;
 | |
|     STRINGLIB_CHAR *src = STRINGLIB_STR(value);
 | |
|     Py_ssize_t len = STRINGLIB_LEN(value);
 | |
|     PyObject *result = NULL;
 | |
| 
 | |
|     /* sign is not allowed on strings */
 | |
|     if (format->sign != '\0') {
 | |
|         PyErr_SetString(PyExc_ValueError,
 | |
|                         "Sign not allowed in string format specifier");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* '=' alignment not allowed on strings */
 | |
|     if (format->align == '=') {
 | |
|         PyErr_SetString(PyExc_ValueError,
 | |
|                         "'=' alignment not allowed "
 | |
|                         "in string format specifier");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* if precision is specified, output no more that format.precision
 | |
|        characters */
 | |
|     if (format->precision >= 0 && len >= format->precision) {
 | |
|         len = format->precision;
 | |
|     }
 | |
| 
 | |
|     if (format->width >= 0) {
 | |
|         width = format->width;
 | |
| 
 | |
|         /* but use at least len characters */
 | |
|         if (len > width) {
 | |
|             width = len;
 | |
|         }
 | |
|     }
 | |
|     else {
 | |
|         /* not specified, use all of the chars and no more */
 | |
|         width = len;
 | |
|     }
 | |
| 
 | |
|     /* allocate the resulting string */
 | |
|     result = STRINGLIB_NEW(NULL, width);
 | |
|     if (result == NULL)
 | |
|         goto done;
 | |
| 
 | |
|     /* now write into that space */
 | |
|     dst = STRINGLIB_STR(result);
 | |
| 
 | |
|     /* figure out how much leading space we need, based on the
 | |
|        aligning */
 | |
|     if (format->align == '>')
 | |
|         lpad = width - len;
 | |
|     else if (format->align == '^')
 | |
|         lpad = (width - len) / 2;
 | |
|     else
 | |
|         lpad = 0;
 | |
| 
 | |
|     /* if right aligning, increment the destination allow space on the
 | |
|        left */
 | |
|     memcpy(dst + lpad, src, len * sizeof(STRINGLIB_CHAR));
 | |
| 
 | |
|     /* do any padding */
 | |
|     if (width > len) {
 | |
|         STRINGLIB_CHAR fill_char = format->fill_char;
 | |
|         if (fill_char == '\0') {
 | |
|             /* use the default, if not specified */
 | |
|             fill_char = ' ';
 | |
|         }
 | |
| 
 | |
|         /* pad on left */
 | |
|         if (lpad)
 | |
|             STRINGLIB_FILL(dst, fill_char, lpad);
 | |
| 
 | |
|         /* pad on right */
 | |
|         if (width - len - lpad)
 | |
|             STRINGLIB_FILL(dst + len + lpad, fill_char, width - len - lpad);
 | |
|     }
 | |
| 
 | |
| done:
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** long formatting ********************************************/
 | |
| /************************************************************************/
 | |
| 
 | |
| static PyObject *
 | |
| format_long_internal(PyObject *value, const InternalFormatSpec *format)
 | |
| {
 | |
|     PyObject *result = NULL;
 | |
|     int total_leading_chars_to_skip = 0; /* also includes sign, if
 | |
|                                             present */
 | |
|     STRINGLIB_CHAR sign = '\0';
 | |
|     STRINGLIB_CHAR *p;
 | |
|     Py_ssize_t n_digits;       /* count of digits need from the computed
 | |
|                                   string */
 | |
|     Py_ssize_t len;
 | |
|     Py_ssize_t tmp;
 | |
|     NumberFieldWidths spec;
 | |
|     long x;
 | |
| 
 | |
|     /* no precision allowed on integers */
 | |
|     if (format->precision != -1) {
 | |
|         PyErr_SetString(PyExc_ValueError,
 | |
|                         "Precision not allowed in integer format specifier");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
| 
 | |
|     /* special case for character formatting */
 | |
|     if (format->type == 'c') {
 | |
|         /* error to specify a sign */
 | |
|         if (format->sign != '\0') {
 | |
|             PyErr_SetString(PyExc_ValueError,
 | |
|                             "Sign not allowed with integer"
 | |
|                             " format specifier 'c'");
 | |
|             goto done;
 | |
|         }
 | |
| 
 | |
|         /* taken from unicodeobject.c formatchar() */
 | |
|         /* Integer input truncated to a character */
 | |
|         x = PyInt_AsLong(value);
 | |
|         if (x == -1 && PyErr_Occurred())
 | |
|             goto done;
 | |
| #ifdef Py_UNICODE_WIDE
 | |
|         if (x < 0 || x > 0x10ffff) {
 | |
|             PyErr_SetString(PyExc_OverflowError,
 | |
|                             "%c arg not in range(0x110000) "
 | |
|                             "(wide Python build)");
 | |
|             goto done;
 | |
|         }
 | |
| #else
 | |
|         if (x < 0 || x > 0xffff) {
 | |
|             PyErr_SetString(PyExc_OverflowError,
 | |
|                             "%c arg not in range(0x10000) "
 | |
|                             "(narrow Python build)");
 | |
|             goto done;
 | |
|         }
 | |
| #endif
 | |
|         result = STRINGLIB_NEW(NULL, 1);
 | |
|         if (result == NULL)
 | |
|             goto done;
 | |
|         p = STRINGLIB_STR(result);
 | |
|         p[0] = (Py_UNICODE) x;
 | |
|         n_digits = len = 1;
 | |
|     }
 | |
|     else {
 | |
|         int base;
 | |
|         int format_leading_chars_to_skip;  /* characters added by
 | |
|                                               PyNumber_ToBase that we
 | |
|                                               want to skip over.
 | |
|                                               instead of using them,
 | |
|                                               we'll compute our
 | |
|                                               own. */
 | |
|         /* compute the base and how many characters will be added by
 | |
|            PyNumber_ToBase */
 | |
|         switch (format->type) {
 | |
|         case 'b':
 | |
|             base = 2;
 | |
|             format_leading_chars_to_skip = 2; /* 0b */
 | |
|             break;
 | |
|         case 'o':
 | |
|             base = 8;
 | |
|             format_leading_chars_to_skip = 2; /* 0o */
 | |
|             break;
 | |
|         case 'x':
 | |
|         case 'X':
 | |
|             base = 16;
 | |
|             format_leading_chars_to_skip = 2; /* 0x */
 | |
|             break;
 | |
|         default:  /* shouldn't be needed, but stops a compiler warning */
 | |
|         case 'd':
 | |
|             base = 10;
 | |
|             format_leading_chars_to_skip = 0;
 | |
|             break;
 | |
|         }
 | |
| 
 | |
|         /* do the hard part, converting to a string in a given base */
 | |
|         result = PyNumber_ToBase(value, base);
 | |
|         if (result == NULL)
 | |
|             goto done;
 | |
| 
 | |
|         n_digits = STRINGLIB_LEN(result);
 | |
|         len = n_digits;
 | |
|         p = STRINGLIB_STR(result);
 | |
| 
 | |
|         /* if X, convert to uppercase */
 | |
|         if (format->type == 'X')
 | |
|             for (tmp = 0; tmp < len; tmp++)
 | |
|                 p[tmp] = STRINGLIB_TOUPPER(p[tmp]);
 | |
| 
 | |
|         /* is a sign character present in the output?  if so, remember it
 | |
|            and skip it */
 | |
|         sign = p[0];
 | |
|         if (sign == '-') {
 | |
|             total_leading_chars_to_skip += 1;
 | |
|             n_digits--;
 | |
|         }
 | |
| 
 | |
|         /* skip over the leading digits (0x, 0b, etc.) */
 | |
|         assert(n_digits >= format_leading_chars_to_skip + 1);
 | |
|         n_digits -= format_leading_chars_to_skip;
 | |
|         total_leading_chars_to_skip += format_leading_chars_to_skip;
 | |
|     }
 | |
| 
 | |
|     calc_number_widths(&spec, sign, n_digits, format);
 | |
| 
 | |
|     /* if the buffer is getting bigger, realloc it.  if it's getting
 | |
|        smaller, don't realloc because we need to move the results
 | |
|        around first.  realloc after we've done that */
 | |
| 
 | |
|     if (spec.n_total > len) {
 | |
|         if (STRINGLIB_RESIZE(&result, spec.n_total) < 0)
 | |
|             goto done;
 | |
|         /* recalc, because string might have moved */
 | |
|         p = STRINGLIB_STR(result);
 | |
|     }
 | |
| 
 | |
|     /* copy the characters into position first, since we're going to
 | |
|        overwrite some of that space */
 | |
|     /* we need to move if the number of left padding in the output is
 | |
|        different from the number of characters we need to skip */
 | |
|     if ((spec.n_lpadding + spec.n_lsign + spec.n_spadding) !=
 | |
|           total_leading_chars_to_skip) {
 | |
|         memmove(p + (spec.n_lpadding + spec.n_lsign + spec.n_spadding),
 | |
|                 p + total_leading_chars_to_skip,
 | |
|                 n_digits * sizeof(STRINGLIB_CHAR));
 | |
|     }
 | |
| 
 | |
|     /* now fill in the non-digit parts */
 | |
|     fill_number(p, &spec, n_digits,
 | |
|                 format->fill_char == '\0' ? ' ' : format->fill_char);
 | |
| 
 | |
|     /* if we're getting smaller, realloc now */
 | |
|     if (spec.n_total < len) {
 | |
|         if (STRINGLIB_RESIZE(&result, spec.n_total) < 0)
 | |
|             goto done;
 | |
|     }
 | |
| 
 | |
| done:
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** float formatting *******************************************/
 | |
| /************************************************************************/
 | |
| 
 | |
| /* taken from unicodeobject.c */
 | |
| static Py_ssize_t
 | |
| strtounicode(Py_UNICODE *buffer, const char *charbuffer)
 | |
| {
 | |
|     register Py_ssize_t i;
 | |
|     Py_ssize_t len = strlen(charbuffer);
 | |
|     for (i = len - 1; i >= 0; i--)
 | |
| 	buffer[i] = (Py_UNICODE) charbuffer[i];
 | |
| 
 | |
|     return len;
 | |
| }
 | |
| 
 | |
| /* the callback function to call to do the actual float formatting.
 | |
|    it matches the definition of PyOS_ascii_formatd */
 | |
| typedef char*
 | |
| (*DoubleSnprintfFunction)(char *buffer, size_t buf_len,
 | |
|                           const char *format, double d);
 | |
| 
 | |
| /* just a wrapper to make PyOS_snprintf look like DoubleSnprintfFunction */
 | |
| static char*
 | |
| snprintf_double(char *buffer, size_t buf_len, const char *format, double d)
 | |
| {
 | |
|     PyOS_snprintf(buffer, buf_len, format, d);
 | |
|     return NULL;
 | |
| }
 | |
| 
 | |
| /* see FORMATBUFLEN in unicodeobject.c */
 | |
| #define FLOAT_FORMATBUFLEN 120
 | |
| 
 | |
| /* much of this is taken from unicodeobject.c */
 | |
| /* use type instead of format->type, so that it can be overridden by
 | |
|    format_number() */
 | |
| static PyObject *
 | |
| _format_float(STRINGLIB_CHAR type, PyObject *value,
 | |
|               const InternalFormatSpec *format,
 | |
|               DoubleSnprintfFunction snprintf)
 | |
| {
 | |
|     /* fmt = '%.' + `prec` + `type` + '%%'
 | |
|        worst case length = 2 + 10 (len of INT_MAX) + 1 + 2 = 15 (use 20)*/
 | |
|     char fmt[20];
 | |
| 
 | |
|     /* taken from unicodeobject.c */
 | |
|     /* Worst case length calc to ensure no buffer overrun:
 | |
| 
 | |
|        'g' formats:
 | |
| 	 fmt = %#.<prec>g
 | |
| 	 buf = '-' + [0-9]*prec + '.' + 'e+' + (longest exp
 | |
| 	    for any double rep.)
 | |
| 	 len = 1 + prec + 1 + 2 + 5 = 9 + prec
 | |
| 
 | |
|        'f' formats:
 | |
| 	 buf = '-' + [0-9]*x + '.' + [0-9]*prec (with x < 50)
 | |
| 	 len = 1 + 50 + 1 + prec = 52 + prec
 | |
| 
 | |
|        If prec=0 the effective precision is 1 (the leading digit is
 | |
|        always given), therefore increase the length by one.
 | |
| 
 | |
|     */
 | |
|     char charbuf[FLOAT_FORMATBUFLEN];
 | |
|     Py_ssize_t n_digits;
 | |
|     double x;
 | |
|     Py_ssize_t precision = format->precision;
 | |
|     PyObject *result = NULL;
 | |
|     STRINGLIB_CHAR sign;
 | |
|     char* trailing = "";
 | |
|     STRINGLIB_CHAR *p;
 | |
|     NumberFieldWidths spec;
 | |
| 
 | |
| #if STRINGLIB_IS_UNICODE
 | |
|     Py_UNICODE unicodebuf[FLOAT_FORMATBUFLEN];
 | |
| #endif
 | |
| 
 | |
|     /* first, do the conversion as 8-bit chars, using the platform's
 | |
|        snprintf.  then, if needed, convert to unicode. */
 | |
| 
 | |
|     /* 'F' is the same as 'f', per the PEP */
 | |
|     if (type == 'F')
 | |
|         type = 'f';
 | |
| 
 | |
|     x = PyFloat_AsDouble(value);
 | |
| 
 | |
|     if (x == -1.0 && PyErr_Occurred())
 | |
| 	goto done;
 | |
| 
 | |
|     if (type == '%') {
 | |
|         type = 'f';
 | |
|         x *= 100;
 | |
|         trailing = "%";
 | |
|     }
 | |
| 
 | |
|     if (precision < 0)
 | |
| 	precision = 6;
 | |
|     if (type == 'f' && (fabs(x) / 1e25) >= 1e25)
 | |
| 	type = 'g';
 | |
| 
 | |
|     /* cast "type", because if we're in unicode we need to pass a
 | |
|        8-bit char.  this is safe, because we've restricted what "type"
 | |
|        can be */
 | |
|     PyOS_snprintf(fmt, sizeof(fmt), "%%.%zd%c", precision, (char)type);
 | |
| 
 | |
|     /* call the passed in function to do the actual formatting */
 | |
|     snprintf(charbuf, sizeof(charbuf), fmt, x);
 | |
| 
 | |
|     /* adding trailing to fmt with PyOS_snprintf doesn't work, not
 | |
|        sure why.  we'll just concatentate it here, no harm done.  we
 | |
|        know we can't have a buffer overflow from the fmt size
 | |
|        analysis */
 | |
|     strcat(charbuf, trailing);
 | |
| 
 | |
|     /* rather than duplicate the code for snprintf for both unicode
 | |
|        and 8 bit strings, we just use the 8 bit version and then
 | |
|        convert to unicode in a separate code path.  that's probably
 | |
|        the lesser of 2 evils. */
 | |
| #if STRINGLIB_IS_UNICODE
 | |
|     n_digits = strtounicode(unicodebuf, charbuf);
 | |
|     p = unicodebuf;
 | |
| #else
 | |
|     /* compute the length.  I believe this is done because the return
 | |
|        value from snprintf above is unreliable */
 | |
|     n_digits = strlen(charbuf);
 | |
|     p = charbuf;
 | |
| #endif
 | |
| 
 | |
|     /* is a sign character present in the output?  if so, remember it
 | |
|        and skip it */
 | |
|     sign = p[0];
 | |
|     if (sign == '-') {
 | |
|         p++;
 | |
|         n_digits--;
 | |
|     }
 | |
| 
 | |
|     calc_number_widths(&spec, sign, n_digits, format);
 | |
| 
 | |
|     /* allocate a string with enough space */
 | |
|     result = STRINGLIB_NEW(NULL, spec.n_total);
 | |
|     if (result == NULL)
 | |
|         goto done;
 | |
| 
 | |
|     /* fill in the non-digit parts */
 | |
|     fill_number(STRINGLIB_STR(result), &spec, n_digits,
 | |
|                 format->fill_char == '\0' ? ' ' : format->fill_char);
 | |
| 
 | |
|     /* fill in the digit parts */
 | |
|     memmove(STRINGLIB_STR(result) + (spec.n_lpadding + spec.n_lsign + spec.n_spadding),
 | |
|             p,
 | |
|             n_digits * sizeof(STRINGLIB_CHAR));
 | |
| 
 | |
| done:
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| static PyObject *
 | |
| format_float_internal(PyObject *value, const InternalFormatSpec *format)
 | |
| {
 | |
|     if (format->type == 'n')
 | |
|         return _format_float('f', value, format, snprintf_double);
 | |
|     else
 | |
|         return _format_float(format->type, value, format, PyOS_ascii_formatd);
 | |
| }
 | |
| 
 | |
| /************************************************************************/
 | |
| /*********** built in formatters ****************************************/
 | |
| /************************************************************************/
 | |
| 
 | |
| PyObject *
 | |
| FORMAT_STRING(PyObject* value, PyObject* args)
 | |
| {
 | |
|     PyObject *format_spec;
 | |
|     PyObject *tmp = NULL;
 | |
|     PyObject *result = NULL;
 | |
|     InternalFormatSpec format;
 | |
| 
 | |
|     if (!PyArg_ParseTuple(args, "O:__format__", &format_spec))
 | |
|         goto done;
 | |
|     if (!STRINGLIB_CHECK(format_spec)) {
 | |
|         PyErr_SetString(PyExc_TypeError, STRINGLIB_TYPE_NAME " object required");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* check for the special case of zero length format spec, make
 | |
|        it equivalent to str(value) */
 | |
|     if (STRINGLIB_LEN(format_spec) == 0) {
 | |
|         result = STRINGLIB_TOSTR(value);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* parse the format_spec */
 | |
|     if (!parse_internal_render_format_spec(format_spec, &format, 's'))
 | |
|         goto done;
 | |
| 
 | |
|     /* type conversion? */
 | |
|     switch (format.type) {
 | |
|     case 's':
 | |
|         /* no type conversion needed, already a string.  do the formatting */
 | |
|         result = format_string_internal(value, &format);
 | |
|         break;
 | |
| #if 0
 | |
|     case 'b':
 | |
|     case 'c':
 | |
|     case 'd':
 | |
|     case 'o':
 | |
|     case 'x':
 | |
|     case 'X':
 | |
|         /* convert to integer */
 | |
|         /* XXX: make a stringlib function to do this when backporting,
 | |
|            since FromUnicode differs from FromString */
 | |
|         tmp = PyLong_FromUnicode(STRINGLIB_STR(value), STRINGLIB_LEN(value), 0);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_long_internal(tmp, &format);
 | |
|         break;
 | |
| 
 | |
|     case 'e':
 | |
|     case 'E':
 | |
|     case 'f':
 | |
|     case 'F':
 | |
|     case 'g':
 | |
|     case 'G':
 | |
|     case 'n':
 | |
|     case '%':
 | |
|         /* convert to float */
 | |
|         tmp = PyFloat_FromString(value);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_float_internal(tmp, &format);
 | |
|         break;
 | |
| #endif
 | |
|     default:
 | |
|         /* unknown */
 | |
|         PyErr_Format(PyExc_ValueError, "Unknown conversion type %c",
 | |
|                      format.type);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
| done:
 | |
|     Py_XDECREF(tmp);
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| PyObject *
 | |
| FORMAT_LONG(PyObject* value, PyObject* args)
 | |
| {
 | |
|     PyObject *format_spec;
 | |
|     PyObject *result = NULL;
 | |
|     PyObject *tmp = NULL;
 | |
|     InternalFormatSpec format;
 | |
| 
 | |
|     if (!PyArg_ParseTuple(args, "O:__format__", &format_spec))
 | |
|         goto done;
 | |
|     if (!STRINGLIB_CHECK(format_spec)) {
 | |
|         PyErr_SetString(PyExc_TypeError, STRINGLIB_TYPE_NAME " object required");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* check for the special case of zero length format spec, make
 | |
|        it equivalent to str(value) */
 | |
|     if (STRINGLIB_LEN(format_spec) == 0) {
 | |
|         result = STRINGLIB_TOSTR(value);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* parse the format_spec */
 | |
|     if (!parse_internal_render_format_spec(format_spec, &format, 'd'))
 | |
|         goto done;
 | |
| 
 | |
|     /* type conversion? */
 | |
|     switch (format.type) {
 | |
| #if 0
 | |
|     case 's':
 | |
|         /* convert to string/unicode */
 | |
|         tmp = STRINGLIB_TOSTR(value);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_string_internal(tmp, &format);
 | |
|         break;
 | |
| #endif
 | |
|     case 'b':
 | |
|     case 'c':
 | |
|     case 'd':
 | |
|     case 'o':
 | |
|     case 'x':
 | |
|     case 'X':
 | |
|         /* no type conversion needed, already an int.  do the formatting */
 | |
|         result = format_long_internal(value, &format);
 | |
|         break;
 | |
| 
 | |
|     case 'e':
 | |
|     case 'E':
 | |
|     case 'f':
 | |
|     case 'F':
 | |
|     case 'g':
 | |
|     case 'G':
 | |
|     case 'n':
 | |
|     case '%':
 | |
|         /* convert to float */
 | |
|         tmp = PyNumber_Float(value);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_float_internal(value, &format);
 | |
|         break;
 | |
| 
 | |
|     default:
 | |
|         /* unknown */
 | |
|         PyErr_Format(PyExc_ValueError, "Unknown conversion type %c",
 | |
|                      format.type);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
| done:
 | |
|     Py_XDECREF(tmp);
 | |
|     return result;
 | |
| }
 | |
| 
 | |
| PyObject *
 | |
| FORMAT_FLOAT(PyObject *value, PyObject *args)
 | |
| {
 | |
|     PyObject *format_spec;
 | |
|     PyObject *result = NULL;
 | |
|     PyObject *tmp = NULL;
 | |
|     InternalFormatSpec format;
 | |
| 
 | |
|     if (!PyArg_ParseTuple(args, "O:__format__", &format_spec))
 | |
|         goto done;
 | |
|     if (!STRINGLIB_CHECK(format_spec)) {
 | |
|         PyErr_SetString(PyExc_TypeError, STRINGLIB_TYPE_NAME " object required");
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* check for the special case of zero length format spec, make
 | |
|        it equivalent to str(value) */
 | |
|     if (STRINGLIB_LEN(format_spec) == 0) {
 | |
|         result = STRINGLIB_TOSTR(value);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
|     /* parse the format_spec */
 | |
|     if (!parse_internal_render_format_spec(format_spec, &format, 'g'))
 | |
|         goto done;
 | |
| 
 | |
|     /* type conversion? */
 | |
|     switch (format.type) {
 | |
| #if 0
 | |
|     case 's':
 | |
|         /* convert to string/unicode */
 | |
|         tmp = STRINGLIB_TOSTR(value);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_string_internal(tmp, &format);
 | |
|         break;
 | |
| #endif
 | |
|     case 'b':
 | |
|     case 'c':
 | |
|     case 'd':
 | |
|     case 'o':
 | |
|     case 'x':
 | |
|     case 'X':
 | |
|         /* convert to integer */
 | |
|         tmp = PyNumber_Long(value);
 | |
|         if (tmp == NULL)
 | |
|             goto done;
 | |
|         result = format_long_internal(tmp, &format);
 | |
|         break;
 | |
| 
 | |
|     case 'e':
 | |
|     case 'E':
 | |
|     case 'f':
 | |
|     case 'F':
 | |
|     case 'g':
 | |
|     case 'G':
 | |
|     case 'n':
 | |
|     case '%':
 | |
|         /* no conversion, already a float.  do the formatting */
 | |
|         result = format_float_internal(value, &format);
 | |
|         break;
 | |
| 
 | |
|     default:
 | |
|         /* unknown */
 | |
|         PyErr_Format(PyExc_ValueError, "Unknown conversion type %c",
 | |
|                      format.type);
 | |
|         goto done;
 | |
|     }
 | |
| 
 | |
| done:
 | |
|     Py_XDECREF(tmp);
 | |
|     return result;
 | |
| }
 | 
