| 1 | /* |
| 2 | * C99-compatible strtod() implementation |
| 3 | * Copyright (c) 2012 Ronald S. Bultje <rsbultje@gmail.com> |
| 4 | * |
| 5 | * This file is part of FFmpeg. |
| 6 | * |
| 7 | * FFmpeg is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU Lesser General Public |
| 9 | * License as published by the Free Software Foundation; either |
| 10 | * version 2.1 of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * FFmpeg is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| 15 | * Lesser General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU Lesser General Public |
| 18 | * License along with FFmpeg; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 20 | */ |
| 21 | |
| 22 | #include <limits.h> |
| 23 | #include <stdlib.h> |
| 24 | |
| 25 | #include "libavutil/avstring.h" |
| 26 | #include "libavutil/mathematics.h" |
| 27 | |
| 28 | static char *check_nan_suffix(char *s) |
| 29 | { |
| 30 | char *start = s; |
| 31 | |
| 32 | if (*s++ != '(') |
| 33 | return start; |
| 34 | |
| 35 | while ((*s >= 'a' && *s <= 'z') || (*s >= 'A' && *s <= 'Z') || |
| 36 | (*s >= '0' && *s <= '9') || *s == '_') |
| 37 | s++; |
| 38 | |
| 39 | return *s == ')' ? s + 1 : start; |
| 40 | } |
| 41 | |
| 42 | #undef strtod |
| 43 | double strtod(const char *, char **); |
| 44 | |
| 45 | double avpriv_strtod(const char *nptr, char **endptr) |
| 46 | { |
| 47 | char *end; |
| 48 | double res; |
| 49 | |
| 50 | /* Skip leading spaces */ |
| 51 | while (av_isspace(*nptr)) |
| 52 | nptr++; |
| 53 | |
| 54 | if (!av_strncasecmp(nptr, "infinity", 8)) { |
| 55 | end = nptr + 8; |
| 56 | res = INFINITY; |
| 57 | } else if (!av_strncasecmp(nptr, "inf", 3)) { |
| 58 | end = nptr + 3; |
| 59 | res = INFINITY; |
| 60 | } else if (!av_strncasecmp(nptr, "+infinity", 9)) { |
| 61 | end = nptr + 9; |
| 62 | res = INFINITY; |
| 63 | } else if (!av_strncasecmp(nptr, "+inf", 4)) { |
| 64 | end = nptr + 4; |
| 65 | res = INFINITY; |
| 66 | } else if (!av_strncasecmp(nptr, "-infinity", 9)) { |
| 67 | end = nptr + 9; |
| 68 | res = -INFINITY; |
| 69 | } else if (!av_strncasecmp(nptr, "-inf", 4)) { |
| 70 | end = nptr + 4; |
| 71 | res = -INFINITY; |
| 72 | } else if (!av_strncasecmp(nptr, "nan", 3)) { |
| 73 | end = check_nan_suffix(nptr + 3); |
| 74 | res = NAN; |
| 75 | } else if (!av_strncasecmp(nptr, "+nan", 4) || |
| 76 | !av_strncasecmp(nptr, "-nan", 4)) { |
| 77 | end = check_nan_suffix(nptr + 4); |
| 78 | res = NAN; |
| 79 | } else if (!av_strncasecmp(nptr, "0x", 2) || |
| 80 | !av_strncasecmp(nptr, "-0x", 3) || |
| 81 | !av_strncasecmp(nptr, "+0x", 3)) { |
| 82 | /* FIXME this doesn't handle exponents, non-integers (float/double) |
| 83 | * and numbers too large for long long */ |
| 84 | res = strtoll(nptr, &end, 16); |
| 85 | } else { |
| 86 | res = strtod(nptr, &end); |
| 87 | } |
| 88 | |
| 89 | if (endptr) |
| 90 | *endptr = end; |
| 91 | |
| 92 | return res; |
| 93 | } |