Mercurial > hg > octave-nkf > gnulib-hg
annotate lib/strtod.c @ 7302:8a1a9361108c
* _fpending.c: Include <config.h> unconditionally, since we no
longer worry about uses that don't define HAVE_CONFIG_H.
* acl.c, alloca.c, argmatch.c, atexit.c, backupfile.c:
* basename.c, c-stack.c, c-strtod.c, calloc.c, canon-host.c:
* canonicalize.c, chdir-long.c, chdir-safer.c, chown.c:
* cloexec.c, close-stream.c, closeout.c, creat-safer.c:
* cycle-check.c, diacrit.c, dirchownmod.c, dirfd.c, dirname.c:
* dup-safer.c, dup2.c, error.c, euidaccess.c, exclude.c:
* exitfail.c, fchmodat.c, fchown-stub.c, fd-safer.c:
* file-type.c, fileblocks.c, filemode.c, filenamecat.c:
* fnmatch.c, fopen-safer.c, fprintftime.c, free.c, fsusage.c:
* ftruncate.c, fts-cycle.c, fts.c, full-write.c, gai_strerror.c:
* getcwd.c, getdate.y, getdomainname.c, getgroups.c:
* gethostname.c, gethrxtime.c, getloadavg.c, getlogin_r.c:
* getndelim2.c, getnline.c, getopt.c, getopt1.c, getpass.c:
* gettime.c, gettimeofday.c, getugroups.c, getusershell.c:
* glob.c, group-member.c, hard-locale.c, hash-pjw.c, hash.c:
* human.c, idcache.c, inet_ntop.c, inet_pton.c, inttostr.c:
* isdir.c, lchown.c, linebuffer.c, long-options.c, lstat.c:
* malloc.c, md5.c, memcasecmp.c, memchr.c, memcmp.c, memcoll.c:
* memcpy.c, memmove.c, memrchr.c, mkancesdirs.c, mkdir-p.c:
* mkdir.c, mkdirat.c, mkstemp-safer.c, mkstemp.c, modechange.c:
* mountlist.c, nanosleep.c, obstack.c, open-safer.c:
* openat-die.c, openat.c, pagealign_alloc.c, physmem.c:
* pipe-safer.c, posixtm.c, posixver.c, putenv.c, quote.c:
* quotearg.c, raise.c, readtokens.c, readtokens0.c, readutmp.c:
* realloc.c, regex.c, rename.c, rmdir.c, rpmatch.c, safe-read.c:
* same.c, save-cwd.c, savedir.c, setenv.c, settime.c, sha1.c:
* sig2str.c, snprintf.c, strdup.c, strerror.c, strftime.c:
* stripslash.c, strndup.c, strnlen.c, strpbrk.c, strtod.c:
* strtoimax.c, strtol.c, strverscmp.c, tempname.c, time_r.c:
* timegm.c, tmpfile-safer.c, unlinkdir.c, userspec.c, utime.c:
* utimecmp.c, utimens.c, version-etc-fsf.c, version-etc.c:
* xalloc-die.c, xgetcwd.c, xgethostname.c, xmalloc.c:
* xmemcoll.c, xnanosleep.c, xreadlink.c, xstrtod.c:
* xstrtoimax.c, xstrtol.c, xstrtoumax.c, yesno.c:
Likewise.
| author | Paul Eggert <eggert@cs.ucla.edu> |
|---|---|
| date | Wed, 13 Sep 2006 22:38:14 +0000 |
| parents | 188d89808804 |
| children | bbbbbf4cd1c5 |
| rev | line source |
|---|---|
|
6834
8094e7d61c3b
* strtod.c [!defined errno]: Assume errno.h declares errno.
Eric Blake <ebb9@byu.net>
parents:
6259
diff
changeset
|
1 /* Copyright (C) 1991, 1992, 1997, 1999, 2003, 2006 Free Software Foundation, Inc. |
| 9 | 2 |
| 311 | 3 This program is free software; you can redistribute it and/or modify |
| 4 it under the terms of the GNU General Public License as published by | |
| 5 the Free Software Foundation; either version 2, or (at your option) | |
| 6 any later version. | |
| 9 | 7 |
| 311 | 8 This program is distributed in the hope that it will be useful, |
| 9 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 10 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 11 GNU General Public License for more details. | |
| 12 | |
| 13 You should have received a copy of the GNU General Public License | |
|
649
89f4c1937ac7
update FSF address in copyright and remove any trailing blanks
Jim Meyering <jim@meyering.net>
parents:
373
diff
changeset
|
14 along with this program; if not, write to the Free Software Foundation, |
|
5848
a48fb0e98c8c
*** empty log message ***
Paul Eggert <eggert@cs.ucla.edu>
parents:
4691
diff
changeset
|
15 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ |
| 309 | 16 |
|
7302
8a1a9361108c
* _fpending.c: Include <config.h> unconditionally, since we no
Paul Eggert <eggert@cs.ucla.edu>
parents:
6930
diff
changeset
|
17 #include <config.h> |
| 311 | 18 |
| 19 #include <errno.h> | |
| 373 | 20 |
| 311 | 21 #include <ctype.h> |
| 1042 | 22 |
| 311 | 23 #include <math.h> |
| 9 | 24 |
| 4691 | 25 #include <float.h> |
| 26 #include <stdlib.h> | |
| 27 #include <string.h> | |
| 9 | 28 |
| 29 /* Convert NPTR to a double. If ENDPTR is not NULL, a pointer to the | |
| 30 character after the last one used in the number is put in *ENDPTR. */ | |
| 31 double | |
| 1691 | 32 strtod (const char *nptr, char **endptr) |
| 9 | 33 { |
| 311 | 34 register const char *s; |
| 9 | 35 short int sign; |
| 36 | |
| 37 /* The number so far. */ | |
| 38 double num; | |
| 39 | |
| 311 | 40 int got_dot; /* Found a decimal point. */ |
| 41 int got_digit; /* Seen any digits. */ | |
| 9 | 42 |
| 43 /* The exponent of the number. */ | |
| 44 long int exponent; | |
| 45 | |
| 46 if (nptr == NULL) | |
| 47 { | |
| 48 errno = EINVAL; | |
| 49 goto noconv; | |
| 50 } | |
| 51 | |
| 52 s = nptr; | |
| 53 | |
| 54 /* Eat whitespace. */ | |
|
6927
fa896bb33133
* lib/memcasecmp.c: Include <limits.h>.
Paul Eggert <eggert@cs.ucla.edu>
parents:
6834
diff
changeset
|
55 while (isspace ((unsigned char) *s)) |
| 9 | 56 ++s; |
| 57 | |
| 58 /* Get the sign. */ | |
| 59 sign = *s == '-' ? -1 : 1; | |
| 60 if (*s == '-' || *s == '+') | |
| 61 ++s; | |
| 62 | |
| 63 num = 0.0; | |
| 64 got_dot = 0; | |
| 65 got_digit = 0; | |
| 66 exponent = 0; | |
| 67 for (;; ++s) | |
| 68 { | |
|
6927
fa896bb33133
* lib/memcasecmp.c: Include <limits.h>.
Paul Eggert <eggert@cs.ucla.edu>
parents:
6834
diff
changeset
|
69 if ('0' <= *s && *s <= '9') |
| 9 | 70 { |
| 71 got_digit = 1; | |
| 72 | |
| 73 /* Make sure that multiplication by 10 will not overflow. */ | |
| 74 if (num > DBL_MAX * 0.1) | |
| 75 /* The value of the digit doesn't matter, since we have already | |
| 76 gotten as many digits as can be represented in a `double'. | |
| 77 This doesn't necessarily mean the result will overflow. | |
| 78 The exponent may reduce it to within range. | |
| 79 | |
| 80 We just need to record that there was another | |
| 81 digit so that we can multiply by 10 later. */ | |
| 82 ++exponent; | |
| 83 else | |
| 84 num = (num * 10.0) + (*s - '0'); | |
| 85 | |
| 86 /* Keep track of the number of digits after the decimal point. | |
| 87 If we just divided by 10 here, we would lose precision. */ | |
| 88 if (got_dot) | |
| 89 --exponent; | |
| 90 } | |
| 311 | 91 else if (!got_dot && *s == '.') |
| 9 | 92 /* Record that we have found the decimal point. */ |
| 93 got_dot = 1; | |
| 94 else | |
| 95 /* Any other character terminates the number. */ | |
| 96 break; | |
| 97 } | |
| 98 | |
| 99 if (!got_digit) | |
| 100 goto noconv; | |
| 101 | |
|
6930
188d89808804
* strtod.c (strtod): cast the argument of tolower to unsigned char.
Ralf Wildenhues <Ralf.Wildenhues@gmx.de>
parents:
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diff
changeset
|
102 if (tolower ((unsigned char) *s) == 'e') |
| 9 | 103 { |
| 104 /* Get the exponent specified after the `e' or `E'. */ | |
| 105 int save = errno; | |
| 106 char *end; | |
| 107 long int exp; | |
| 108 | |
| 109 errno = 0; | |
| 110 ++s; | |
| 311 | 111 exp = strtol (s, &end, 10); |
| 9 | 112 if (errno == ERANGE) |
| 113 { | |
| 114 /* The exponent overflowed a `long int'. It is probably a safe | |
| 115 assumption that an exponent that cannot be represented by | |
| 116 a `long int' exceeds the limits of a `double'. */ | |
| 117 if (endptr != NULL) | |
| 118 *endptr = end; | |
| 119 if (exp < 0) | |
| 120 goto underflow; | |
| 121 else | |
| 122 goto overflow; | |
| 123 } | |
| 124 else if (end == s) | |
| 125 /* There was no exponent. Reset END to point to | |
| 126 the 'e' or 'E', so *ENDPTR will be set there. */ | |
| 127 end = (char *) s - 1; | |
| 128 errno = save; | |
| 129 s = end; | |
| 130 exponent += exp; | |
| 131 } | |
| 132 | |
| 133 if (endptr != NULL) | |
| 134 *endptr = (char *) s; | |
| 135 | |
| 136 if (num == 0.0) | |
| 137 return 0.0; | |
| 138 | |
| 139 /* Multiply NUM by 10 to the EXPONENT power, | |
| 140 checking for overflow and underflow. */ | |
| 141 | |
| 142 if (exponent < 0) | |
| 143 { | |
| 311 | 144 if (num < DBL_MIN * pow (10.0, (double) -exponent)) |
| 9 | 145 goto underflow; |
| 146 } | |
| 147 else if (exponent > 0) | |
| 148 { | |
| 311 | 149 if (num > DBL_MAX * pow (10.0, (double) -exponent)) |
| 9 | 150 goto overflow; |
| 151 } | |
| 152 | |
| 311 | 153 num *= pow (10.0, (double) exponent); |
| 9 | 154 |
| 155 return num * sign; | |
| 156 | |
| 311 | 157 overflow: |
| 9 | 158 /* Return an overflow error. */ |
| 159 errno = ERANGE; | |
| 160 return HUGE_VAL * sign; | |
| 161 | |
| 311 | 162 underflow: |
| 9 | 163 /* Return an underflow error. */ |
| 164 if (endptr != NULL) | |
| 165 *endptr = (char *) nptr; | |
| 166 errno = ERANGE; | |
| 167 return 0.0; | |
| 168 | |
| 311 | 169 noconv: |
| 9 | 170 /* There was no number. */ |
| 171 if (endptr != NULL) | |
| 172 *endptr = (char *) nptr; | |
| 173 return 0.0; | |
| 174 } |