69 lines
1.5 KiB
C
69 lines
1.5 KiB
C
/* fgets function */
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#include <string.h>
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#include "xstdio.h"
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_STD_BEGIN
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char *(fgets)(char *_Restrict buf, int n, FILE *_Restrict str)
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{ /* get a line from stream */
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unsigned char *s = (unsigned char *)buf;
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if (n <= 1)
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return (0);
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--n;
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_Lockfileatomic(str);
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if ((str->_Mode & _MBYTE) != 0)
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for (; 0 < n
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&& str->_Rback < str->_Back + sizeof (str->_Back); --n)
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{ /* deliver pushed back chars */
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*s = *str->_Rback++;
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if (*s++ == '\n')
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n = 1; /* terminate full line */
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}
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while (0 < n)
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{ /* ensure buffer has chars */
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if (str->_Rsave != 0)
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str->_Rend = str->_Rsave, str->_Rsave = 0;
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if (str->_Next < str->_Rend)
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;
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else if (_Frprep(str) < 0)
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{ /* nothing to read */
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_Unlockfileatomic(str);
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return (0);
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}
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else if (str->_Mode & _MEOF)
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break;
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{ /* copy as many as possible */
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unsigned char *s1 =
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(unsigned char *)memchr((void *)str->_Next,
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'\n', str->_Rend - str->_Next);
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size_t m = (s1 ? s1 + 1 : str->_Rend) - str->_Next;
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if ((size_t)n < m)
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s1 = 0, m = n;
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memcpy(s, str->_Next, m);
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s += m, n -= m;
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str->_Next += m;
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if (s1 != 0)
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break; /* full line, quit */
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}
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}
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if (s == (unsigned char *)buf)
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buf = 0; /* nothing read, report failure */
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else
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*s = '\0'; /* terminate partial line */
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_Unlockfileatomic(str);
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return (buf);
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}
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_STD_END
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/*
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* Copyright (c) 1992-2006 by P.J. Plauger. ALL RIGHTS RESERVED.
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* Consult your license regarding permissions and restrictions.
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V5.00:1296 */
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__SRCVERSION("fgets.c $Rev: 153052 $");
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