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93 lines
2.4 KiB
C
93 lines
2.4 KiB
C
/* linebuffer.c -- read arbitrarily long lines
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Copyright (C) 1986, 1991, 1998, 1999 Free Software Foundation, Inc.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 2, or (at your option)
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any later version.
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This program 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 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 Richard Stallman. */
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#ifdef 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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#include "linebuffer.h"
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char *xmalloc ();
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char *xrealloc ();
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void free ();
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/* Initialize linebuffer LINEBUFFER for use. */
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void
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initbuffer (struct linebuffer *linebuffer)
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{
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linebuffer->length = 0;
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linebuffer->size = 200;
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linebuffer->buffer = (char *) xmalloc (linebuffer->size);
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}
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/* Read an arbitrarily long line of text from STREAM into LINEBUFFER.
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Keep the newline; append a newline if it's the last line of a file
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that ends in a non-newline character. Do not null terminate.
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Return LINEBUFFER, except at end of file return 0. */
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struct linebuffer *
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readline (struct linebuffer *linebuffer, FILE *stream)
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{
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int c;
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char *buffer = linebuffer->buffer;
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char *p = linebuffer->buffer;
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char *end = buffer + linebuffer->size; /* Sentinel. */
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if (feof (stream) || ferror (stream))
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return 0;
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do
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{
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c = getc (stream);
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if (c == EOF)
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{
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if (p == buffer)
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return 0;
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if (p[-1] == '\n')
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break;
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c = '\n';
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}
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if (p == end)
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{
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linebuffer->size *= 2;
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buffer = (char *) xrealloc (buffer, linebuffer->size);
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p = p - linebuffer->buffer + buffer;
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linebuffer->buffer = buffer;
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end = buffer + linebuffer->size;
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}
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*p++ = c;
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}
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while (c != '\n');
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linebuffer->length = p - buffer;
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return linebuffer;
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}
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/* Free linebuffer LINEBUFFER and its data, all allocated with malloc. */
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void
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freebuffer (struct linebuffer *linebuffer)
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{
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free (linebuffer->buffer);
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free (linebuffer);
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}
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