diff options
Diffstat (limited to 'erts/emulator/sys/win32/sys_float.c')
| -rw-r--r-- | erts/emulator/sys/win32/sys_float.c | 145 |
1 files changed, 145 insertions, 0 deletions
diff --git a/erts/emulator/sys/win32/sys_float.c b/erts/emulator/sys/win32/sys_float.c new file mode 100644 index 0000000000..9e67ca7f48 --- /dev/null +++ b/erts/emulator/sys/win32/sys_float.c @@ -0,0 +1,145 @@ +/* + * %CopyrightBegin% + * + * Copyright Ericsson AB 1997-2009. All Rights Reserved. + * + * The contents of this file are subject to the Erlang Public License, + * Version 1.1, (the "License"); you may not use this file except in + * compliance with the License. You should have received a copy of the + * Erlang Public License along with this software. If not, it can be + * retrieved online at http://www.erlang.org/. + * + * Software distributed under the License is distributed on an "AS IS" + * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See + * the License for the specific language governing rights and limitations + * under the License. + * + * %CopyrightEnd% + */ +/* Float conversions */ + +#include "sys.h" +#include "signal.h" + +/* global variable for floating point checks, (see sys.h) */ +/* Note! This is part of the interface Machine <---> sys.c */ +volatile int erl_fp_exception = 0; + +static void fpe_exception(int sig); + +void +erts_sys_init_float(void) +{ +} +void erts_thread_init_float(void) +{ +} +void erts_thread_disable_fpe(void) +{ +} + +/* + ** These two functions should maybe use localeconv() to pick up + ** the current radix character, but since it is uncertain how + ** expensive such a system call is, and since no-one has heard + ** of other radix characters than '.' and ',' an ad-hoc + ** low execution time solution is used instead. + */ + +int +sys_chars_to_double(char *buf, double *fp) +{ + char *s = buf, *t, *dp; + + /* Robert says that something like this is what he really wanted: + * (The [.,] radix test is NOT what Robert wanted - it was added later) + * + * 7 == sscanf(Tbuf, "%[+-]%[0-9][.,]%[0-9]%[eE]%[+-]%[0-9]%s", ....); + * if (*s2 == 0 || *s3 == 0 || *s4 == 0 || *s6 == 0 || *s7) + * break; + */ + + /* Scan string to check syntax. */ + if (*s == '+' || *s == '-') s++; + if (!isdigit(*s)) /* Leading digits. */ + return -1; + while (isdigit(*s)) s++; + if (*s != '.' && *s != ',')/* Decimal part. */ + return -1; + dp = s++; /* Remember decimal point pos just in case */ + if (!isdigit(*s)) + return -1; + while (isdigit(*s)) s++; + if (*s == 'e' || *s == 'E') { + /* There is an exponent. */ + s++; + if (*s == '+' || *s == '-') s++; + if (!isdigit(*s)) + return -1; + while (isdigit(*s)) s++; + } + if (*s) /* That should be it */ + return -1; + + errno = 0; + *fp = strtod(buf, &t); + if (t != s) { /* Whole string not scanned */ + /* Try again with other radix char */ + *dp = (*dp == '.') ? ',' : '.'; + errno = 0; + *fp = strtod(buf, &t); + if (t != s) { /* Whole string not scanned */ + return -1; + } + } + if (*fp < -1.0e-307 || 1.0e-307 < *fp) { + if (errno == ERANGE) { + return -1; + } + } else { + if (errno == ERANGE) { + /* Special case: Windows (at least some) regard very small + * i.e non-normalized numbers as a range error for strtod(). + * But not for atof. + */ + *fp = atof(buf); + } + } + + return 0; +} + +/* +** Convert a double to ascii format 0.dddde[+|-]ddd +** return number of characters converted +*/ + +int +sys_double_to_chars(double fp, char *buf) +{ + char *s = buf; + + (void) sprintf(buf, "%.20e", fp); + /* Search upto decimal point */ + if (*s == '+' || *s == '-') s++; + while (isdigit(*s)) s++; + if (*s == ',') *s++ = '.'; /* Replace ',' with '.' */ + /* Scan to end of string */ + while (*s) s++; + return s-buf; /* i.e strlen(buf) */ +} + +int +matherr(struct _exception *exc) +{ + erl_fp_exception = 1; + DEBUGF(("FP exception (matherr) (0x%x) (%d)\n", exc->type, erl_fp_exception)); + return 1; +} + +static void +fpe_exception(int sig) +{ + erl_fp_exception = 1; + DEBUGF(("FP exception\n")); +} |