Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 1 | /* -*- Mode: C; c-file-style: "python" -*- */ |
| 2 | |
| 3 | #include <Python.h> |
| 4 | #include <locale.h> |
| 5 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 6 | /** |
| 7 | * PyOS_ascii_strtod: |
| 8 | * @nptr: the string to convert to a numeric value. |
| 9 | * @endptr: if non-%NULL, it returns the character after |
| 10 | * the last character used in the conversion. |
| 11 | * |
| 12 | * Converts a string to a #gdouble value. |
| 13 | * This function behaves like the standard strtod() function |
| 14 | * does in the C locale. It does this without actually |
| 15 | * changing the current locale, since that would not be |
| 16 | * thread-safe. |
| 17 | * |
| 18 | * This function is typically used when reading configuration |
| 19 | * files or other non-user input that should be locale independent. |
| 20 | * To handle input from the user you should normally use the |
| 21 | * locale-sensitive system strtod() function. |
| 22 | * |
| 23 | * If the correct value would cause overflow, plus or minus %HUGE_VAL |
| 24 | * is returned (according to the sign of the value), and %ERANGE is |
| 25 | * stored in %errno. If the correct value would cause underflow, |
| 26 | * zero is returned and %ERANGE is stored in %errno. |
Thomas Wouters | 4d70c3d | 2006-06-08 14:42:34 +0000 | [diff] [blame] | 27 | * If memory allocation fails, %ENOMEM is stored in %errno. |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 28 | * |
| 29 | * This function resets %errno before calling strtod() so that |
| 30 | * you can reliably detect overflow and underflow. |
| 31 | * |
| 32 | * Return value: the #gdouble value. |
| 33 | **/ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 34 | |
| 35 | #ifndef PY_NO_SHORT_FLOAT_REPR |
| 36 | |
| 37 | double |
| 38 | PyOS_ascii_strtod(const char *nptr, char **endptr) |
| 39 | { |
| 40 | double result; |
| 41 | _Py_SET_53BIT_PRECISION_HEADER; |
| 42 | |
| 43 | assert(nptr != NULL); |
| 44 | /* Set errno to zero, so that we can distinguish zero results |
| 45 | and underflows */ |
| 46 | errno = 0; |
| 47 | |
| 48 | _Py_SET_53BIT_PRECISION_START; |
| 49 | result = _Py_dg_strtod(nptr, endptr); |
| 50 | _Py_SET_53BIT_PRECISION_END; |
| 51 | |
| 52 | return result; |
| 53 | |
| 54 | } |
| 55 | |
| 56 | #else |
| 57 | |
| 58 | /* |
| 59 | Use system strtod; since strtod is locale aware, we may |
| 60 | have to first fix the decimal separator. |
| 61 | |
| 62 | Note that unlike _Py_dg_strtod, the system strtod may not always give |
| 63 | correctly rounded results. |
| 64 | */ |
| 65 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 66 | double |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 67 | PyOS_ascii_strtod(const char *nptr, char **endptr) |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 68 | { |
| 69 | char *fail_pos; |
Neal Norwitz | 0e7a0ed | 2005-12-18 05:37:36 +0000 | [diff] [blame] | 70 | double val = -1.0; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 71 | struct lconv *locale_data; |
| 72 | const char *decimal_point; |
Neal Norwitz | d39d861 | 2006-01-08 01:03:36 +0000 | [diff] [blame] | 73 | size_t decimal_point_len; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 74 | const char *p, *decimal_point_pos; |
| 75 | const char *end = NULL; /* Silence gcc */ |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 76 | const char *digits_pos = NULL; |
| 77 | int negate = 0; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 78 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 79 | assert(nptr != NULL); |
| 80 | |
| 81 | fail_pos = NULL; |
| 82 | |
| 83 | locale_data = localeconv(); |
| 84 | decimal_point = locale_data->decimal_point; |
| 85 | decimal_point_len = strlen(decimal_point); |
| 86 | |
| 87 | assert(decimal_point_len != 0); |
| 88 | |
| 89 | decimal_point_pos = NULL; |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 90 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 91 | /* Set errno to zero, so that we can distinguish zero results |
| 92 | and underflows */ |
| 93 | errno = 0; |
| 94 | |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 95 | /* We process any leading whitespace and the optional sign manually, |
| 96 | then pass the remainder to the system strtod. This ensures that |
| 97 | the result of an underflow has the correct sign. (bug #1725) */ |
| 98 | |
| 99 | p = nptr; |
| 100 | /* Skip leading space */ |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 101 | while (Py_ISSPACE(*p)) |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 102 | p++; |
| 103 | |
| 104 | /* Process leading sign, if present */ |
| 105 | if (*p == '-') { |
| 106 | negate = 1; |
| 107 | p++; |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 108 | } |
| 109 | else if (*p == '+') { |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 110 | p++; |
| 111 | } |
| 112 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 113 | /* Parse infinities and nans */ |
| 114 | if (*p == 'i' || *p == 'I') { |
| 115 | if (PyOS_strnicmp(p, "inf", 3) == 0) { |
| 116 | val = Py_HUGE_VAL; |
| 117 | if (PyOS_strnicmp(p+3, "inity", 5) == 0) |
| 118 | fail_pos = (char *)p+8; |
| 119 | else |
| 120 | fail_pos = (char *)p+3; |
| 121 | goto got_val; |
| 122 | } |
| 123 | else |
| 124 | goto invalid_string; |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 125 | } |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 126 | #ifdef Py_NAN |
| 127 | if (*p == 'n' || *p == 'N') { |
| 128 | if (PyOS_strnicmp(p, "nan", 3) == 0) { |
| 129 | val = Py_NAN; |
| 130 | fail_pos = (char *)p+3; |
| 131 | goto got_val; |
| 132 | } |
| 133 | else |
| 134 | goto invalid_string; |
| 135 | } |
| 136 | #endif |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 137 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 138 | /* Some platform strtods accept hex floats; Python shouldn't (at the |
| 139 | moment), so we check explicitly for strings starting with '0x'. */ |
| 140 | if (*p == '0' && (*(p+1) == 'x' || *(p+1) == 'X')) |
| 141 | goto invalid_string; |
| 142 | |
| 143 | /* Check that what's left begins with a digit or decimal point */ |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 144 | if (!Py_ISDIGIT(*p) && *p != '.') |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 145 | goto invalid_string; |
| 146 | |
| 147 | digits_pos = p; |
| 148 | if (decimal_point[0] != '.' || |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 149 | decimal_point[1] != 0) |
| 150 | { |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 151 | /* Look for a '.' in the input; if present, it'll need to be |
| 152 | swapped for the current locale's decimal point before we |
| 153 | call strtod. On the other hand, if we find the current |
| 154 | locale's decimal point then the input is invalid. */ |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 155 | while (Py_ISDIGIT(*p)) |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 156 | p++; |
| 157 | |
| 158 | if (*p == '.') |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 159 | { |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 160 | decimal_point_pos = p++; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 161 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 162 | /* locate end of number */ |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 163 | while (Py_ISDIGIT(*p)) |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 164 | p++; |
| 165 | |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 166 | if (*p == 'e' || *p == 'E') |
| 167 | p++; |
| 168 | if (*p == '+' || *p == '-') |
| 169 | p++; |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 170 | while (Py_ISDIGIT(*p)) |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 171 | p++; |
| 172 | end = p; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 173 | } |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 174 | else if (strncmp(p, decimal_point, decimal_point_len) == 0) |
Thomas Wouters | 0e3f591 | 2006-08-11 14:57:12 +0000 | [diff] [blame] | 175 | /* Python bug #1417699 */ |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 176 | goto invalid_string; |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 177 | /* For the other cases, we need not convert the decimal |
| 178 | point */ |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 179 | } |
| 180 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 181 | if (decimal_point_pos) { |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 182 | char *copy, *c; |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 183 | /* Create a copy of the input, with the '.' converted to the |
| 184 | locale-specific decimal point */ |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 185 | copy = (char *)PyMem_MALLOC(end - digits_pos + |
| 186 | 1 + decimal_point_len); |
Thomas Wouters | 4d70c3d | 2006-06-08 14:42:34 +0000 | [diff] [blame] | 187 | if (copy == NULL) { |
| 188 | if (endptr) |
| 189 | *endptr = (char *)nptr; |
| 190 | errno = ENOMEM; |
| 191 | return val; |
| 192 | } |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 193 | |
| 194 | c = copy; |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 195 | memcpy(c, digits_pos, decimal_point_pos - digits_pos); |
| 196 | c += decimal_point_pos - digits_pos; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 197 | memcpy(c, decimal_point, decimal_point_len); |
| 198 | c += decimal_point_len; |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 199 | memcpy(c, decimal_point_pos + 1, |
| 200 | end - (decimal_point_pos + 1)); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 201 | c += end - (decimal_point_pos + 1); |
| 202 | *c = 0; |
| 203 | |
| 204 | val = strtod(copy, &fail_pos); |
| 205 | |
| 206 | if (fail_pos) |
| 207 | { |
| 208 | if (fail_pos > decimal_point_pos) |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 209 | fail_pos = (char *)digits_pos + |
| 210 | (fail_pos - copy) - |
| 211 | (decimal_point_len - 1); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 212 | else |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 213 | fail_pos = (char *)digits_pos + |
| 214 | (fail_pos - copy); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 215 | } |
| 216 | |
Thomas Wouters | 477c8d5 | 2006-05-27 19:21:47 +0000 | [diff] [blame] | 217 | PyMem_FREE(copy); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 218 | |
| 219 | } |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 220 | else { |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 221 | val = strtod(digits_pos, &fail_pos); |
Neal Norwitz | e7214a1 | 2005-12-18 05:03:17 +0000 | [diff] [blame] | 222 | } |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 223 | |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 224 | if (fail_pos == digits_pos) |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 225 | goto invalid_string; |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 226 | |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 227 | got_val: |
Christian Heimes | faf2f63 | 2008-01-06 16:59:19 +0000 | [diff] [blame] | 228 | if (negate && fail_pos != nptr) |
| 229 | val = -val; |
| 230 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 231 | if (endptr) |
| 232 | *endptr = fail_pos; |
| 233 | |
| 234 | return val; |
Mark Dickinson | 6d65df1 | 2009-04-26 15:30:47 +0000 | [diff] [blame] | 235 | |
| 236 | invalid_string: |
| 237 | if (endptr) |
| 238 | *endptr = (char*)nptr; |
| 239 | errno = EINVAL; |
| 240 | return -1.0; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 241 | } |
| 242 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 243 | #endif |
| 244 | |
| 245 | double |
| 246 | PyOS_ascii_atof(const char *nptr) |
| 247 | { |
| 248 | return PyOS_ascii_strtod(nptr, NULL); |
| 249 | } |
| 250 | |
| 251 | |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 252 | /* Given a string that may have a decimal point in the current |
| 253 | locale, change it back to a dot. Since the string cannot get |
| 254 | longer, no need for a maximum buffer size parameter. */ |
| 255 | Py_LOCAL_INLINE(void) |
| 256 | change_decimal_from_locale_to_dot(char* buffer) |
| 257 | { |
| 258 | struct lconv *locale_data = localeconv(); |
| 259 | const char *decimal_point = locale_data->decimal_point; |
| 260 | |
| 261 | if (decimal_point[0] != '.' || decimal_point[1] != 0) { |
| 262 | size_t decimal_point_len = strlen(decimal_point); |
| 263 | |
| 264 | if (*buffer == '+' || *buffer == '-') |
| 265 | buffer++; |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 266 | while (Py_ISDIGIT(*buffer)) |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 267 | buffer++; |
| 268 | if (strncmp(buffer, decimal_point, decimal_point_len) == 0) { |
| 269 | *buffer = '.'; |
| 270 | buffer++; |
| 271 | if (decimal_point_len > 1) { |
| 272 | /* buffer needs to get smaller */ |
| 273 | size_t rest_len = strlen(buffer + |
| 274 | (decimal_point_len - 1)); |
| 275 | memmove(buffer, |
| 276 | buffer + (decimal_point_len - 1), |
| 277 | rest_len); |
| 278 | buffer[rest_len] = 0; |
| 279 | } |
| 280 | } |
| 281 | } |
| 282 | } |
| 283 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 284 | |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 285 | /* From the C99 standard, section 7.19.6: |
| 286 | The exponent always contains at least two digits, and only as many more digits |
| 287 | as necessary to represent the exponent. |
| 288 | */ |
| 289 | #define MIN_EXPONENT_DIGITS 2 |
| 290 | |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 291 | /* Ensure that any exponent, if present, is at least MIN_EXPONENT_DIGITS |
| 292 | in length. */ |
| 293 | Py_LOCAL_INLINE(void) |
Mark Dickinson | ce95e56 | 2009-04-26 20:02:24 +0000 | [diff] [blame] | 294 | ensure_minimum_exponent_length(char* buffer, size_t buf_size) |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 295 | { |
| 296 | char *p = strpbrk(buffer, "eE"); |
| 297 | if (p && (*(p + 1) == '-' || *(p + 1) == '+')) { |
| 298 | char *start = p + 2; |
| 299 | int exponent_digit_cnt = 0; |
| 300 | int leading_zero_cnt = 0; |
| 301 | int in_leading_zeros = 1; |
| 302 | int significant_digit_cnt; |
| 303 | |
| 304 | /* Skip over the exponent and the sign. */ |
| 305 | p += 2; |
| 306 | |
| 307 | /* Find the end of the exponent, keeping track of leading |
| 308 | zeros. */ |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 309 | while (*p && Py_ISDIGIT(*p)) { |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 310 | if (in_leading_zeros && *p == '0') |
| 311 | ++leading_zero_cnt; |
| 312 | if (*p != '0') |
| 313 | in_leading_zeros = 0; |
| 314 | ++p; |
| 315 | ++exponent_digit_cnt; |
| 316 | } |
| 317 | |
| 318 | significant_digit_cnt = exponent_digit_cnt - leading_zero_cnt; |
| 319 | if (exponent_digit_cnt == MIN_EXPONENT_DIGITS) { |
| 320 | /* If there are 2 exactly digits, we're done, |
| 321 | regardless of what they contain */ |
| 322 | } |
| 323 | else if (exponent_digit_cnt > MIN_EXPONENT_DIGITS) { |
| 324 | int extra_zeros_cnt; |
| 325 | |
| 326 | /* There are more than 2 digits in the exponent. See |
| 327 | if we can delete some of the leading zeros */ |
| 328 | if (significant_digit_cnt < MIN_EXPONENT_DIGITS) |
| 329 | significant_digit_cnt = MIN_EXPONENT_DIGITS; |
| 330 | extra_zeros_cnt = exponent_digit_cnt - |
| 331 | significant_digit_cnt; |
| 332 | |
| 333 | /* Delete extra_zeros_cnt worth of characters from the |
| 334 | front of the exponent */ |
| 335 | assert(extra_zeros_cnt >= 0); |
| 336 | |
| 337 | /* Add one to significant_digit_cnt to copy the |
| 338 | trailing 0 byte, thus setting the length */ |
| 339 | memmove(start, |
| 340 | start + extra_zeros_cnt, |
| 341 | significant_digit_cnt + 1); |
| 342 | } |
| 343 | else { |
| 344 | /* If there are fewer than 2 digits, add zeros |
| 345 | until there are 2, if there's enough room */ |
| 346 | int zeros = MIN_EXPONENT_DIGITS - exponent_digit_cnt; |
| 347 | if (start + zeros + exponent_digit_cnt + 1 |
| 348 | < buffer + buf_size) { |
| 349 | memmove(start + zeros, start, |
| 350 | exponent_digit_cnt + 1); |
| 351 | memset(start, '0', zeros); |
| 352 | } |
| 353 | } |
| 354 | } |
| 355 | } |
| 356 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 357 | /* Ensure that buffer has a decimal point in it. The decimal point will not |
| 358 | be in the current locale, it will always be '.'. Don't add a decimal if an |
| 359 | exponent is present. */ |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 360 | Py_LOCAL_INLINE(void) |
| 361 | ensure_decimal_point(char* buffer, size_t buf_size) |
| 362 | { |
| 363 | int insert_count = 0; |
| 364 | char* chars_to_insert; |
| 365 | |
| 366 | /* search for the first non-digit character */ |
| 367 | char *p = buffer; |
Eric Smith | 2ad79e8 | 2008-07-19 00:33:23 +0000 | [diff] [blame] | 368 | if (*p == '-' || *p == '+') |
| 369 | /* Skip leading sign, if present. I think this could only |
| 370 | ever be '-', but it can't hurt to check for both. */ |
| 371 | ++p; |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 372 | while (*p && Py_ISDIGIT(*p)) |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 373 | ++p; |
| 374 | |
| 375 | if (*p == '.') { |
Eric Smith | 6dc46f5 | 2009-04-27 20:39:49 +0000 | [diff] [blame^] | 376 | if (Py_ISDIGIT(*(p+1))) { |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 377 | /* Nothing to do, we already have a decimal |
| 378 | point and a digit after it */ |
| 379 | } |
| 380 | else { |
| 381 | /* We have a decimal point, but no following |
| 382 | digit. Insert a zero after the decimal. */ |
| 383 | ++p; |
| 384 | chars_to_insert = "0"; |
| 385 | insert_count = 1; |
| 386 | } |
| 387 | } |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 388 | else if (!(*p == 'e' || *p == 'E')) { |
| 389 | /* Don't add ".0" if we have an exponent. */ |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 390 | chars_to_insert = ".0"; |
| 391 | insert_count = 2; |
| 392 | } |
| 393 | if (insert_count) { |
| 394 | size_t buf_len = strlen(buffer); |
| 395 | if (buf_len + insert_count + 1 >= buf_size) { |
| 396 | /* If there is not enough room in the buffer |
| 397 | for the additional text, just skip it. It's |
| 398 | not worth generating an error over. */ |
| 399 | } |
| 400 | else { |
| 401 | memmove(p + insert_count, p, |
| 402 | buffer + strlen(buffer) - p + 1); |
| 403 | memcpy(p, chars_to_insert, insert_count); |
| 404 | } |
| 405 | } |
| 406 | } |
| 407 | |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 408 | /* see FORMATBUFLEN in unicodeobject.c */ |
| 409 | #define FLOAT_FORMATBUFLEN 120 |
| 410 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 411 | /** |
| 412 | * PyOS_ascii_formatd: |
| 413 | * @buffer: A buffer to place the resulting string in |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 414 | * @buf_size: The length of the buffer. |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 415 | * @format: The printf()-style format to use for the |
| 416 | * code to use for converting. |
| 417 | * @d: The #gdouble to convert |
| 418 | * |
| 419 | * Converts a #gdouble to a string, using the '.' as |
| 420 | * decimal point. To format the number you pass in |
| 421 | * a printf()-style format string. Allowed conversion |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 422 | * specifiers are 'e', 'E', 'f', 'F', 'g', 'G', and 'Z'. |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 423 | * |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 424 | * 'Z' is the same as 'g', except it always has a decimal and |
| 425 | * at least one digit after the decimal. |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 426 | * |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 427 | * Return value: The pointer to the buffer with the converted string. |
| 428 | **/ |
| 429 | char * |
Eric Smith | cc32a11 | 2009-04-26 21:35:14 +0000 | [diff] [blame] | 430 | _PyOS_ascii_formatd(char *buffer, |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 431 | size_t buf_size, |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 432 | const char *format, |
| 433 | double d) |
| 434 | { |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 435 | char format_char; |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 436 | size_t format_len = strlen(format); |
| 437 | |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 438 | /* Issue 2264: code 'Z' requires copying the format. 'Z' is 'g', but |
| 439 | also with at least one character past the decimal. */ |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 440 | char tmp_format[FLOAT_FORMATBUFLEN]; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 441 | |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 442 | /* The last character in the format string must be the format char */ |
| 443 | format_char = format[format_len - 1]; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 444 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 445 | if (format[0] != '%') |
| 446 | return NULL; |
| 447 | |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 448 | /* I'm not sure why this test is here. It's ensuring that the format |
| 449 | string after the first character doesn't have a single quote, a |
| 450 | lowercase l, or a percent. This is the reverse of the commented-out |
| 451 | test about 10 lines ago. */ |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 452 | if (strpbrk(format + 1, "'l%")) |
| 453 | return NULL; |
| 454 | |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 455 | /* Also curious about this function is that it accepts format strings |
| 456 | like "%xg", which are invalid for floats. In general, the |
| 457 | interface to this function is not very good, but changing it is |
| 458 | difficult because it's a public API. */ |
| 459 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 460 | if (!(format_char == 'e' || format_char == 'E' || |
| 461 | format_char == 'f' || format_char == 'F' || |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 462 | format_char == 'g' || format_char == 'G' || |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 463 | format_char == 'Z')) |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 464 | return NULL; |
| 465 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 466 | /* Map 'Z' format_char to 'g', by copying the format string and |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 467 | replacing the final char with a 'g' */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 468 | if (format_char == 'Z') { |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 469 | if (format_len + 1 >= sizeof(tmp_format)) { |
| 470 | /* The format won't fit in our copy. Error out. In |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 471 | practice, this will never happen and will be |
| 472 | detected by returning NULL */ |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 473 | return NULL; |
| 474 | } |
| 475 | strcpy(tmp_format, format); |
| 476 | tmp_format[format_len - 1] = 'g'; |
| 477 | format = tmp_format; |
| 478 | } |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 479 | |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 480 | |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 481 | /* Have PyOS_snprintf do the hard work */ |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 482 | PyOS_snprintf(buffer, buf_size, format, d); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 483 | |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 484 | /* Do various fixups on the return string */ |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 485 | |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 486 | /* Get the current locale, and find the decimal point string. |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 487 | Convert that string back to a dot. */ |
| 488 | change_decimal_from_locale_to_dot(buffer); |
Christian Heimes | c3f30c4 | 2008-02-22 16:37:40 +0000 | [diff] [blame] | 489 | |
| 490 | /* If an exponent exists, ensure that the exponent is at least |
| 491 | MIN_EXPONENT_DIGITS digits, providing the buffer is large enough |
| 492 | for the extra zeros. Also, if there are more than |
| 493 | MIN_EXPONENT_DIGITS, remove as many zeros as possible until we get |
| 494 | back to MIN_EXPONENT_DIGITS */ |
Mark Dickinson | ce95e56 | 2009-04-26 20:02:24 +0000 | [diff] [blame] | 495 | ensure_minimum_exponent_length(buffer, buf_size); |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 496 | |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 497 | /* If format_char is 'Z', make sure we have at least one character |
| 498 | after the decimal point (and make sure we have a decimal point). */ |
Eric Smith | b2c7af8 | 2008-04-30 02:12:09 +0000 | [diff] [blame] | 499 | if (format_char == 'Z') |
| 500 | ensure_decimal_point(buffer, buf_size); |
Christian Heimes | b186d00 | 2008-03-18 15:15:01 +0000 | [diff] [blame] | 501 | |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 502 | return buffer; |
| 503 | } |
| 504 | |
Eric Smith | cc32a11 | 2009-04-26 21:35:14 +0000 | [diff] [blame] | 505 | char * |
| 506 | PyOS_ascii_formatd(char *buffer, |
| 507 | size_t buf_size, |
| 508 | const char *format, |
| 509 | double d) |
| 510 | { |
| 511 | if (PyErr_WarnEx(PyExc_DeprecationWarning, |
| 512 | "PyOS_ascii_formatd is deprecated, " |
| 513 | "use PyOS_double_to_string instead", 1) < 0) |
| 514 | return NULL; |
| 515 | |
| 516 | return _PyOS_ascii_formatd(buffer, buf_size, format, d); |
| 517 | } |
| 518 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 519 | #ifdef PY_NO_SHORT_FLOAT_REPR |
| 520 | |
| 521 | /* The fallback code to use if _Py_dg_dtoa is not available. */ |
| 522 | |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 523 | /* Remove trailing zeros after the decimal point from a numeric string; also |
| 524 | remove the decimal point if all digits following it are zero. The numeric |
| 525 | string must end in '\0', and should not have any leading or trailing |
| 526 | whitespace. Assumes that the decimal point is '.'. */ |
| 527 | Py_LOCAL_INLINE(void) |
| 528 | remove_trailing_zeros(char *buffer) |
| 529 | { |
| 530 | char *old_fraction_end, *new_fraction_end, *end, *p; |
| 531 | |
| 532 | p = buffer; |
| 533 | if (*p == '-' || *p == '+') |
| 534 | /* Skip leading sign, if present */ |
| 535 | ++p; |
| 536 | while (isdigit(Py_CHARMASK(*p))) |
| 537 | ++p; |
| 538 | |
| 539 | /* if there's no decimal point there's nothing to do */ |
| 540 | if (*p++ != '.') |
| 541 | return; |
| 542 | |
| 543 | /* scan any digits after the point */ |
| 544 | while (isdigit(Py_CHARMASK(*p))) |
| 545 | ++p; |
| 546 | old_fraction_end = p; |
| 547 | |
| 548 | /* scan up to ending '\0' */ |
| 549 | while (*p != '\0') |
| 550 | p++; |
| 551 | /* +1 to make sure that we move the null byte as well */ |
| 552 | end = p+1; |
| 553 | |
| 554 | /* scan back from fraction_end, looking for removable zeros */ |
| 555 | p = old_fraction_end; |
| 556 | while (*(p-1) == '0') |
| 557 | --p; |
| 558 | /* and remove point if we've got that far */ |
| 559 | if (*(p-1) == '.') |
| 560 | --p; |
| 561 | new_fraction_end = p; |
| 562 | |
| 563 | memmove(new_fraction_end, old_fraction_end, end-old_fraction_end); |
| 564 | } |
| 565 | |
| 566 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 567 | PyAPI_FUNC(char *) PyOS_double_to_string(double val, |
| 568 | char format_code, |
| 569 | int precision, |
| 570 | int flags, |
| 571 | int *type) |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 572 | { |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 573 | char buf[128]; |
| 574 | char format[32]; |
| 575 | Py_ssize_t len; |
| 576 | char *result; |
| 577 | char *p; |
| 578 | int t; |
| 579 | int upper = 0; |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 580 | int strip_trailing_zeros = 0; |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 581 | |
| 582 | /* Validate format_code, and map upper and lower case */ |
| 583 | switch (format_code) { |
| 584 | case 'e': /* exponent */ |
| 585 | case 'f': /* fixed */ |
| 586 | case 'g': /* general */ |
| 587 | break; |
| 588 | case 'E': |
| 589 | upper = 1; |
| 590 | format_code = 'e'; |
| 591 | break; |
| 592 | case 'F': |
| 593 | upper = 1; |
| 594 | format_code = 'f'; |
| 595 | break; |
| 596 | case 'G': |
| 597 | upper = 1; |
| 598 | format_code = 'g'; |
| 599 | break; |
| 600 | case 'r': /* repr format */ |
| 601 | /* Supplied precision is unused, must be 0. */ |
| 602 | if (precision != 0) { |
| 603 | PyErr_BadInternalCall(); |
| 604 | return NULL; |
| 605 | } |
| 606 | precision = 17; |
| 607 | format_code = 'g'; |
| 608 | break; |
| 609 | case 's': /* str format */ |
| 610 | /* Supplied precision is unused, must be 0. */ |
| 611 | if (precision != 0) { |
| 612 | PyErr_BadInternalCall(); |
| 613 | return NULL; |
| 614 | } |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 615 | /* switch to exponential notation at 1e11, or 1e12 if we're |
| 616 | not adding a .0 */ |
| 617 | if (fabs(val) >= (flags & Py_DTSF_ADD_DOT_0 ? 1e11 : 1e12)) { |
| 618 | precision = 11; |
| 619 | format_code = 'e'; |
| 620 | strip_trailing_zeros = 1; |
| 621 | } |
| 622 | else { |
| 623 | precision = 12; |
| 624 | format_code = 'g'; |
| 625 | } |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 626 | break; |
| 627 | default: |
| 628 | PyErr_BadInternalCall(); |
| 629 | return NULL; |
| 630 | } |
| 631 | |
| 632 | /* Handle nan and inf. */ |
| 633 | if (Py_IS_NAN(val)) { |
| 634 | strcpy(buf, "nan"); |
| 635 | t = Py_DTST_NAN; |
| 636 | } else if (Py_IS_INFINITY(val)) { |
| 637 | if (copysign(1., val) == 1.) |
| 638 | strcpy(buf, "inf"); |
| 639 | else |
| 640 | strcpy(buf, "-inf"); |
| 641 | t = Py_DTST_INFINITE; |
| 642 | } else { |
| 643 | t = Py_DTST_FINITE; |
| 644 | |
| 645 | |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 646 | if ((flags & Py_DTSF_ADD_DOT_0) && (format_code != 'e')) |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 647 | format_code = 'Z'; |
| 648 | |
Eric Smith | cc32a11 | 2009-04-26 21:35:14 +0000 | [diff] [blame] | 649 | PyOS_snprintf(format, sizeof(format), "%%%s.%i%c", |
| 650 | (flags & Py_DTSF_ALT ? "#" : ""), precision, |
| 651 | format_code); |
| 652 | _PyOS_ascii_formatd(buf, sizeof(buf), format, val); |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 653 | /* remove trailing zeros if necessary */ |
| 654 | if (strip_trailing_zeros) |
| 655 | remove_trailing_zeros(buf); |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 656 | } |
| 657 | |
| 658 | len = strlen(buf); |
| 659 | |
| 660 | /* Add 1 for the trailing 0 byte. |
| 661 | Add 1 because we might need to make room for the sign. |
| 662 | */ |
| 663 | result = PyMem_Malloc(len + 2); |
| 664 | if (result == NULL) { |
| 665 | PyErr_NoMemory(); |
| 666 | return NULL; |
| 667 | } |
| 668 | p = result; |
| 669 | |
Mark Dickinson | ad476da | 2009-04-23 19:14:16 +0000 | [diff] [blame] | 670 | /* Add sign when requested. It's convenient (esp. when formatting |
| 671 | complex numbers) to include a sign even for inf and nan. */ |
| 672 | if (flags & Py_DTSF_SIGN && buf[0] != '-') |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 673 | *p++ = '+'; |
| 674 | |
| 675 | strcpy(p, buf); |
| 676 | |
| 677 | if (upper) { |
| 678 | /* Convert to upper case. */ |
| 679 | char *p1; |
| 680 | for (p1 = p; *p1; p1++) |
| 681 | *p1 = toupper(*p1); |
| 682 | } |
| 683 | |
| 684 | if (type) |
| 685 | *type = t; |
| 686 | return result; |
Martin v. Löwis | 737ea82 | 2004-06-08 18:52:54 +0000 | [diff] [blame] | 687 | } |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 688 | |
| 689 | #else |
| 690 | |
| 691 | /* _Py_dg_dtoa is available. */ |
| 692 | |
| 693 | /* I'm using a lookup table here so that I don't have to invent a non-locale |
| 694 | specific way to convert to uppercase */ |
| 695 | #define OFS_INF 0 |
| 696 | #define OFS_NAN 1 |
| 697 | #define OFS_E 2 |
| 698 | |
| 699 | /* The lengths of these are known to the code below, so don't change them */ |
| 700 | static char *lc_float_strings[] = { |
| 701 | "inf", |
| 702 | "nan", |
| 703 | "e", |
| 704 | }; |
| 705 | static char *uc_float_strings[] = { |
| 706 | "INF", |
| 707 | "NAN", |
| 708 | "E", |
| 709 | }; |
| 710 | |
| 711 | |
| 712 | /* Convert a double d to a string, and return a PyMem_Malloc'd block of |
| 713 | memory contain the resulting string. |
| 714 | |
| 715 | Arguments: |
| 716 | d is the double to be converted |
| 717 | format_code is one of 'e', 'f', 'g', 'r' or 's'. 'e', 'f' and 'g' |
| 718 | correspond to '%e', '%f' and '%g'; 'r' and 's' correspond |
| 719 | to repr and str. |
| 720 | mode is one of '0', '2' or '3', and is completely determined by |
| 721 | format_code: 'e', 'g' and 's' use mode 2; 'f' mode 3, 'r' mode 0. |
| 722 | precision is the desired precision |
| 723 | always_add_sign is nonzero if a '+' sign should be included for positive |
| 724 | numbers |
| 725 | add_dot_0_if_integer is nonzero if integers in non-exponential form |
| 726 | should have ".0" added. Only applies to format codes 'r', 's', and 'g'. |
| 727 | use_alt_formatting is nonzero if alternative formatting should be |
| 728 | used. Only applies to format codes 'e', 'f' and 'g'. |
| 729 | type, if non-NULL, will be set to one of these constants to identify |
| 730 | the type of the 'd' argument: |
| 731 | Py_DTST_FINITE |
| 732 | Py_DTST_INFINITE |
| 733 | Py_DTST_NAN |
| 734 | |
| 735 | Returns a PyMem_Malloc'd block of memory containing the resulting string, |
| 736 | or NULL on error. If NULL is returned, the Python error has been set. |
| 737 | */ |
| 738 | |
| 739 | static char * |
| 740 | format_float_short(double d, char format_code, |
| 741 | int mode, Py_ssize_t precision, |
| 742 | int always_add_sign, int add_dot_0_if_integer, |
| 743 | int use_alt_formatting, char **float_strings, int *type) |
| 744 | { |
| 745 | char *buf = NULL; |
| 746 | char *p = NULL; |
| 747 | Py_ssize_t bufsize = 0; |
| 748 | char *digits, *digits_end; |
| 749 | int decpt_as_int, sign, exp_len, exp = 0, use_exp = 0; |
| 750 | Py_ssize_t decpt, digits_len, vdigits_start, vdigits_end; |
| 751 | _Py_SET_53BIT_PRECISION_HEADER; |
| 752 | |
| 753 | /* _Py_dg_dtoa returns a digit string (no decimal point or exponent). |
| 754 | Must be matched by a call to _Py_dg_freedtoa. */ |
| 755 | _Py_SET_53BIT_PRECISION_START; |
| 756 | digits = _Py_dg_dtoa(d, mode, precision, &decpt_as_int, &sign, |
| 757 | &digits_end); |
| 758 | _Py_SET_53BIT_PRECISION_END; |
| 759 | |
| 760 | decpt = (Py_ssize_t)decpt_as_int; |
| 761 | if (digits == NULL) { |
| 762 | /* The only failure mode is no memory. */ |
| 763 | PyErr_NoMemory(); |
| 764 | goto exit; |
| 765 | } |
| 766 | assert(digits_end != NULL && digits_end >= digits); |
| 767 | digits_len = digits_end - digits; |
| 768 | |
Mark Dickinson | 3370cce | 2009-04-17 22:40:53 +0000 | [diff] [blame] | 769 | if (digits_len && !isdigit(Py_CHARMASK(digits[0]))) { |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 770 | /* Infinities and nans here; adapt Gay's output, |
| 771 | so convert Infinity to inf and NaN to nan, and |
| 772 | ignore sign of nan. Then return. */ |
| 773 | |
Mark Dickinson | ad476da | 2009-04-23 19:14:16 +0000 | [diff] [blame] | 774 | /* ignore the actual sign of a nan */ |
| 775 | if (digits[0] == 'n' || digits[0] == 'N') |
| 776 | sign = 0; |
| 777 | |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 778 | /* We only need 5 bytes to hold the result "+inf\0" . */ |
| 779 | bufsize = 5; /* Used later in an assert. */ |
| 780 | buf = (char *)PyMem_Malloc(bufsize); |
| 781 | if (buf == NULL) { |
| 782 | PyErr_NoMemory(); |
| 783 | goto exit; |
| 784 | } |
| 785 | p = buf; |
| 786 | |
Mark Dickinson | ad476da | 2009-04-23 19:14:16 +0000 | [diff] [blame] | 787 | if (sign == 1) { |
| 788 | *p++ = '-'; |
| 789 | } |
| 790 | else if (always_add_sign) { |
| 791 | *p++ = '+'; |
| 792 | } |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 793 | if (digits[0] == 'i' || digits[0] == 'I') { |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 794 | strncpy(p, float_strings[OFS_INF], 3); |
| 795 | p += 3; |
| 796 | |
| 797 | if (type) |
| 798 | *type = Py_DTST_INFINITE; |
| 799 | } |
| 800 | else if (digits[0] == 'n' || digits[0] == 'N') { |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 801 | strncpy(p, float_strings[OFS_NAN], 3); |
| 802 | p += 3; |
| 803 | |
| 804 | if (type) |
| 805 | *type = Py_DTST_NAN; |
| 806 | } |
| 807 | else { |
| 808 | /* shouldn't get here: Gay's code should always return |
| 809 | something starting with a digit, an 'I', or 'N' */ |
| 810 | strncpy(p, "ERR", 3); |
| 811 | p += 3; |
| 812 | assert(0); |
| 813 | } |
| 814 | goto exit; |
| 815 | } |
| 816 | |
| 817 | /* The result must be finite (not inf or nan). */ |
| 818 | if (type) |
| 819 | *type = Py_DTST_FINITE; |
| 820 | |
| 821 | |
| 822 | /* We got digits back, format them. We may need to pad 'digits' |
| 823 | either on the left or right (or both) with extra zeros, so in |
| 824 | general the resulting string has the form |
| 825 | |
| 826 | [<sign>]<zeros><digits><zeros>[<exponent>] |
| 827 | |
| 828 | where either of the <zeros> pieces could be empty, and there's a |
| 829 | decimal point that could appear either in <digits> or in the |
| 830 | leading or trailing <zeros>. |
| 831 | |
| 832 | Imagine an infinite 'virtual' string vdigits, consisting of the |
| 833 | string 'digits' (starting at index 0) padded on both the left and |
| 834 | right with infinite strings of zeros. We want to output a slice |
| 835 | |
| 836 | vdigits[vdigits_start : vdigits_end] |
| 837 | |
| 838 | of this virtual string. Thus if vdigits_start < 0 then we'll end |
| 839 | up producing some leading zeros; if vdigits_end > digits_len there |
| 840 | will be trailing zeros in the output. The next section of code |
| 841 | determines whether to use an exponent or not, figures out the |
| 842 | position 'decpt' of the decimal point, and computes 'vdigits_start' |
| 843 | and 'vdigits_end'. */ |
| 844 | vdigits_end = digits_len; |
| 845 | switch (format_code) { |
| 846 | case 'e': |
| 847 | use_exp = 1; |
| 848 | vdigits_end = precision; |
| 849 | break; |
| 850 | case 'f': |
| 851 | vdigits_end = decpt + precision; |
| 852 | break; |
| 853 | case 'g': |
| 854 | if (decpt <= -4 || decpt > precision) |
| 855 | use_exp = 1; |
| 856 | if (use_alt_formatting) |
| 857 | vdigits_end = precision; |
| 858 | break; |
| 859 | case 'r': |
| 860 | /* convert to exponential format at 1e16. We used to convert |
| 861 | at 1e17, but that gives odd-looking results for some values |
| 862 | when a 16-digit 'shortest' repr is padded with bogus zeros. |
| 863 | For example, repr(2e16+8) would give 20000000000000010.0; |
| 864 | the true value is 20000000000000008.0. */ |
| 865 | if (decpt <= -4 || decpt > 16) |
| 866 | use_exp = 1; |
| 867 | break; |
| 868 | case 's': |
| 869 | /* if we're forcing a digit after the point, convert to |
| 870 | exponential format at 1e11. If not, convert at 1e12. */ |
| 871 | if (decpt <= -4 || decpt > |
| 872 | (add_dot_0_if_integer ? precision-1 : precision)) |
| 873 | use_exp = 1; |
| 874 | break; |
| 875 | default: |
| 876 | PyErr_BadInternalCall(); |
| 877 | goto exit; |
| 878 | } |
| 879 | |
| 880 | /* if using an exponent, reset decimal point position to 1 and adjust |
| 881 | exponent accordingly.*/ |
| 882 | if (use_exp) { |
| 883 | exp = decpt - 1; |
| 884 | decpt = 1; |
| 885 | } |
| 886 | /* ensure vdigits_start < decpt <= vdigits_end, or vdigits_start < |
| 887 | decpt < vdigits_end if add_dot_0_if_integer and no exponent */ |
| 888 | vdigits_start = decpt <= 0 ? decpt-1 : 0; |
| 889 | if (!use_exp && add_dot_0_if_integer) |
| 890 | vdigits_end = vdigits_end > decpt ? vdigits_end : decpt + 1; |
| 891 | else |
| 892 | vdigits_end = vdigits_end > decpt ? vdigits_end : decpt; |
| 893 | |
| 894 | /* double check inequalities */ |
| 895 | assert(vdigits_start <= 0 && |
| 896 | 0 <= digits_len && |
| 897 | digits_len <= vdigits_end); |
| 898 | /* decimal point should be in (vdigits_start, vdigits_end] */ |
| 899 | assert(vdigits_start < decpt && decpt <= vdigits_end); |
| 900 | |
| 901 | /* Compute an upper bound how much memory we need. This might be a few |
| 902 | chars too long, but no big deal. */ |
| 903 | bufsize = |
| 904 | /* sign, decimal point and trailing 0 byte */ |
| 905 | 3 + |
| 906 | |
| 907 | /* total digit count (including zero padding on both sides) */ |
| 908 | (vdigits_end - vdigits_start) + |
| 909 | |
| 910 | /* exponent "e+100", max 3 numerical digits */ |
| 911 | (use_exp ? 5 : 0); |
| 912 | |
| 913 | /* Now allocate the memory and initialize p to point to the start of |
| 914 | it. */ |
| 915 | buf = (char *)PyMem_Malloc(bufsize); |
| 916 | if (buf == NULL) { |
| 917 | PyErr_NoMemory(); |
| 918 | goto exit; |
| 919 | } |
| 920 | p = buf; |
| 921 | |
| 922 | /* Add a negative sign if negative, and a plus sign if non-negative |
| 923 | and always_add_sign is true. */ |
| 924 | if (sign == 1) |
| 925 | *p++ = '-'; |
| 926 | else if (always_add_sign) |
| 927 | *p++ = '+'; |
| 928 | |
| 929 | /* note that exactly one of the three 'if' conditions is true, |
| 930 | so we include exactly one decimal point */ |
| 931 | /* Zero padding on left of digit string */ |
| 932 | if (decpt <= 0) { |
| 933 | memset(p, '0', decpt-vdigits_start); |
| 934 | p += decpt - vdigits_start; |
| 935 | *p++ = '.'; |
| 936 | memset(p, '0', 0-decpt); |
| 937 | p += 0-decpt; |
| 938 | } |
| 939 | else { |
| 940 | memset(p, '0', 0-vdigits_start); |
| 941 | p += 0 - vdigits_start; |
| 942 | } |
| 943 | |
| 944 | /* Digits, with included decimal point */ |
| 945 | if (0 < decpt && decpt <= digits_len) { |
| 946 | strncpy(p, digits, decpt-0); |
| 947 | p += decpt-0; |
| 948 | *p++ = '.'; |
| 949 | strncpy(p, digits+decpt, digits_len-decpt); |
| 950 | p += digits_len-decpt; |
| 951 | } |
| 952 | else { |
| 953 | strncpy(p, digits, digits_len); |
| 954 | p += digits_len; |
| 955 | } |
| 956 | |
| 957 | /* And zeros on the right */ |
| 958 | if (digits_len < decpt) { |
| 959 | memset(p, '0', decpt-digits_len); |
| 960 | p += decpt-digits_len; |
| 961 | *p++ = '.'; |
| 962 | memset(p, '0', vdigits_end-decpt); |
| 963 | p += vdigits_end-decpt; |
| 964 | } |
| 965 | else { |
| 966 | memset(p, '0', vdigits_end-digits_len); |
| 967 | p += vdigits_end-digits_len; |
| 968 | } |
| 969 | |
| 970 | /* Delete a trailing decimal pt unless using alternative formatting. */ |
| 971 | if (p[-1] == '.' && !use_alt_formatting) |
| 972 | p--; |
| 973 | |
| 974 | /* Now that we've done zero padding, add an exponent if needed. */ |
| 975 | if (use_exp) { |
| 976 | *p++ = float_strings[OFS_E][0]; |
| 977 | exp_len = sprintf(p, "%+.02d", exp); |
| 978 | p += exp_len; |
| 979 | } |
| 980 | exit: |
| 981 | if (buf) { |
| 982 | *p = '\0'; |
| 983 | /* It's too late if this fails, as we've already stepped on |
| 984 | memory that isn't ours. But it's an okay debugging test. */ |
| 985 | assert(p-buf < bufsize); |
| 986 | } |
| 987 | if (digits) |
| 988 | _Py_dg_freedtoa(digits); |
| 989 | |
| 990 | return buf; |
| 991 | } |
| 992 | |
| 993 | |
| 994 | PyAPI_FUNC(char *) PyOS_double_to_string(double val, |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 995 | char format_code, |
| 996 | int precision, |
| 997 | int flags, |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 998 | int *type) |
| 999 | { |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1000 | char **float_strings = lc_float_strings; |
| 1001 | int mode; |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1002 | |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1003 | /* Validate format_code, and map upper and lower case. Compute the |
| 1004 | mode and make any adjustments as needed. */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1005 | switch (format_code) { |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1006 | /* exponent */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1007 | case 'E': |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1008 | float_strings = uc_float_strings; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1009 | format_code = 'e'; |
| 1010 | /* Fall through. */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1011 | case 'e': |
| 1012 | mode = 2; |
| 1013 | precision++; |
| 1014 | break; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1015 | |
| 1016 | /* fixed */ |
| 1017 | case 'F': |
| 1018 | float_strings = uc_float_strings; |
| 1019 | format_code = 'f'; |
| 1020 | /* Fall through. */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1021 | case 'f': |
| 1022 | mode = 3; |
| 1023 | break; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1024 | |
| 1025 | /* general */ |
| 1026 | case 'G': |
| 1027 | float_strings = uc_float_strings; |
| 1028 | format_code = 'g'; |
| 1029 | /* Fall through. */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1030 | case 'g': |
| 1031 | mode = 2; |
| 1032 | /* precision 0 makes no sense for 'g' format; interpret as 1 */ |
| 1033 | if (precision == 0) |
| 1034 | precision = 1; |
| 1035 | break; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1036 | |
| 1037 | /* repr format */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1038 | case 'r': |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1039 | mode = 0; |
| 1040 | /* Supplied precision is unused, must be 0. */ |
| 1041 | if (precision != 0) { |
| 1042 | PyErr_BadInternalCall(); |
| 1043 | return NULL; |
| 1044 | } |
| 1045 | break; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1046 | |
| 1047 | /* str format */ |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1048 | case 's': |
| 1049 | mode = 2; |
| 1050 | /* Supplied precision is unused, must be 0. */ |
| 1051 | if (precision != 0) { |
| 1052 | PyErr_BadInternalCall(); |
| 1053 | return NULL; |
| 1054 | } |
| 1055 | precision = 12; |
| 1056 | break; |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1057 | |
| 1058 | default: |
| 1059 | PyErr_BadInternalCall(); |
| 1060 | return NULL; |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1061 | } |
| 1062 | |
Eric Smith | 193125a | 2009-04-16 22:08:31 +0000 | [diff] [blame] | 1063 | return format_float_short(val, format_code, mode, precision, |
Eric Smith | 0923d1d | 2009-04-16 20:16:10 +0000 | [diff] [blame] | 1064 | flags & Py_DTSF_SIGN, |
| 1065 | flags & Py_DTSF_ADD_DOT_0, |
| 1066 | flags & Py_DTSF_ALT, |
| 1067 | float_strings, type); |
| 1068 | } |
| 1069 | #endif /* ifdef PY_NO_SHORT_FLOAT_REPR */ |