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https://github.com/coreutils/coreutils.git
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923091ff96
(getstr): Remove warning-evoking assertions. Return -1 if offset parameter is out of bounds. Change the type of a local from int to size_t.
116 lines
3.0 KiB
C
116 lines
3.0 KiB
C
/* getstr.c -- core function for GNU C library getline replacement function
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Copyright (C) 1993, 1996-2001 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or
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modify it under the terms of the GNU General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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This program is distributed in the hope that it will be useful, but
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WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; if not, write to the Free Software Foundation,
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Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
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/* Written by Jan Brittenson, bson@gnu.ai.mit.edu. */
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#if HAVE_CONFIG_H
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# include <config.h>
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#endif
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#include <stdio.h>
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#include <sys/types.h>
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#if STDC_HEADERS
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# include <stdlib.h>
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#else
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char *malloc (), *realloc ();
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#endif
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#include "unlocked-io.h"
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/* Always add at least this many bytes when extending the buffer. */
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#define MIN_CHUNK 64
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/* Read up to (and including) a delimiter DELIM1 from STREAM into *LINEPTR
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+ OFFSET (and NUL-terminate it). If DELIM2 is non-zero, then read up
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and including the first occurrence of DELIM1 or DELIM2. *LINEPTR is
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a pointer returned from malloc (or NULL), pointing to *N characters of
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space. It is realloc'd as necessary. Return the number of characters
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read (not including the NUL terminator), or -1 on error or EOF. */
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int
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getstr (char **lineptr, size_t *n, FILE *stream, int delim1, int delim2,
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size_t offset)
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{
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size_t nchars_avail; /* Allocated but unused chars in *LINEPTR. */
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char *read_pos; /* Where we're reading into *LINEPTR. */
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int ret;
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if (!lineptr || !n || !stream)
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return -1;
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if (!*lineptr)
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{
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*n = MIN_CHUNK;
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*lineptr = malloc (*n);
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if (!*lineptr)
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return -1;
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}
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if (*n < offset)
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return -1;
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nchars_avail = *n - offset;
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read_pos = *lineptr + offset;
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for (;;)
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{
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register int c = getc (stream);
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/* We always want at least one char left in the buffer, since we
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always (unless we get an error while reading the first char)
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NUL-terminate the line buffer. */
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if (nchars_avail < 2)
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{
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if (*n > MIN_CHUNK)
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*n *= 2;
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else
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*n += MIN_CHUNK;
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nchars_avail = *n + *lineptr - read_pos;
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*lineptr = realloc (*lineptr, *n);
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if (!*lineptr)
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return -1;
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read_pos = *n - nchars_avail + *lineptr;
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}
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if (c == EOF || ferror (stream))
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{
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/* Return partial line, if any. */
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if (read_pos == *lineptr)
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return -1;
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else
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break;
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}
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*read_pos++ = c;
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nchars_avail--;
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if (c == delim1 || (delim2 && c == delim2))
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/* Return the line. */
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break;
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}
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/* Done - NUL terminate and return the number of chars read. */
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*read_pos = '\0';
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ret = read_pos - (*lineptr + offset);
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return ret;
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}
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