50 lines
1.6 KiB
C
50 lines
1.6 KiB
C
/*---------------------------------------------------------------------
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atoi - convert a string to an integer and return it
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written By - Sandeep Dutta . sandeep.dutta@usa.net (1999)
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This library is free software; you can redistribute it and/or modify it
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under the terms of the GNU Library General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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This library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU Library General Public License for more details.
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You should have received a copy of the GNU Library General Public License
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along with this program; if not, write to the Free Software
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Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
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In other words, you are welcome to use, share and improve this program.
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You are forbidden to forbid anyone else to use, share and improve
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what you give them. Help stamp out software-hoarding!
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-------------------------------------------------------------------------*/
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int atoi(char * s)
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{
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register int rv=0;
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register char sign = 0;
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/* skip till we find either a digit or '+' or '-' */
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while (*s) {
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if (*s <= '9' && *s >= '0')
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break;
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if (*s == '-' || *s == '+')
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break;
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s++;
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}
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sign = (*s == '-');
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if (*s == '-' || *s == '+') s++;
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while (*s && *s >= '0' && *s <= '9') {
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rv = (rv * 10) + (*s - '0');
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s++;
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}
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return (sign ? -rv : rv);
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}
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