1 /* linebuffer.c -- read arbitrarily long lines
3 Copyright (C) 1986, 1991, 1998, 1999, 2001, 2003, 2004, 2006, 2007
4 Free Software Foundation, Inc.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software Foundation,
18 Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */
20 /* Written by Richard Stallman. */
27 #include <sys/types.h>
28 #include "linebuffer.h"
32 # include "unlocked-io.h"
35 /* Initialize linebuffer LINEBUFFER for use. */
38 initbuffer (struct linebuffer *linebuffer)
40 memset (linebuffer, 0, sizeof *linebuffer);
44 readlinebuffer (struct linebuffer *linebuffer, FILE *stream)
46 return readlinebuffer_delim (linebuffer, stream, '\n');
49 /* Read an arbitrarily long line of text from STREAM into LINEBUFFER.
50 Consider lines to be terminated by DELIMITER.
51 Keep the delimiter; append DELIMITER if it's the last line of a file
52 that ends in a character other than DELIMITER. Do not NUL-terminate.
53 Therefore the stream can contain NUL bytes, and the length
54 (including the delimiter) is returned in linebuffer->length.
55 Return NULL when stream is empty. Return NULL and set errno upon
56 error; callers can distinguish this case from the empty case by
57 invoking ferror (stream).
58 Otherwise, return LINEBUFFER. */
60 readlinebuffer_delim (struct linebuffer *linebuffer, FILE *stream,
64 char *buffer = linebuffer->buffer;
65 char *p = linebuffer->buffer;
66 char *end = buffer + linebuffer->size; /* Sentinel. */
76 if (p == buffer || ferror (stream))
78 if (p[-1] == delimiter)
84 size_t oldsize = linebuffer->size;
85 buffer = x2realloc (buffer, &linebuffer->size);
87 linebuffer->buffer = buffer;
88 end = buffer + linebuffer->size;
92 while (c != delimiter);
94 linebuffer->length = p - buffer;
98 /* Free the buffer that was allocated for linebuffer LINEBUFFER. */
101 freebuffer (struct linebuffer *linebuffer)
103 free (linebuffer->buffer);