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author | Lorry Tar Creator <lorry-tar-importer@lorry> | 2007-03-22 21:23:21 +0000 |
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committer | Lorry Tar Creator <lorry-tar-importer@lorry> | 2007-03-22 21:23:21 +0000 |
commit | cbf5993c43f49281173f185863577d86bfac6eae (patch) | |
tree | 90737c96cf15b97273a2bdc5950b3cf09f1d94ca /lib/linebuffer.c | |
download | coreutils-tarball-cbf5993c43f49281173f185863577d86bfac6eae.tar.gz |
coreutils-6.9coreutils-6.9
Diffstat (limited to 'lib/linebuffer.c')
-rw-r--r-- | lib/linebuffer.c | 96 |
1 files changed, 96 insertions, 0 deletions
diff --git a/lib/linebuffer.c b/lib/linebuffer.c new file mode 100644 index 0000000..3f1e45b --- /dev/null +++ b/lib/linebuffer.c @@ -0,0 +1,96 @@ +/* linebuffer.c -- read arbitrarily long lines + + Copyright (C) 1986, 1991, 1998, 1999, 2001, 2003, 2004, 2006 Free + Software Foundation, Inc. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. */ + +/* Written by Richard Stallman. */ + +#include <config.h> + +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <sys/types.h> +#include "linebuffer.h" +#include "xalloc.h" + +#if USE_UNLOCKED_IO +# include "unlocked-io.h" +#endif + +/* Initialize linebuffer LINEBUFFER for use. */ + +void +initbuffer (struct linebuffer *linebuffer) +{ + memset (linebuffer, 0, sizeof *linebuffer); +} + +/* Read an arbitrarily long line of text from STREAM into LINEBUFFER. + Keep the newline; append a newline if it's the last line of a file + that ends in a non-newline character. Do not null terminate. + Therefore the stream can contain NUL bytes, and the length + (including the newline) is returned in linebuffer->length. + Return NULL when stream is empty. Return NULL and set errno upon + error; callers can distinguish this case from the empty case by + invoking ferror (stream). + Otherwise, return LINEBUFFER. */ +struct linebuffer * +readlinebuffer (struct linebuffer *linebuffer, FILE *stream) +{ + int c; + char *buffer = linebuffer->buffer; + char *p = linebuffer->buffer; + char *end = buffer + linebuffer->size; /* Sentinel. */ + + if (feof (stream)) + return NULL; + + do + { + c = getc (stream); + if (c == EOF) + { + if (p == buffer || ferror (stream)) + return NULL; + if (p[-1] == '\n') + break; + c = '\n'; + } + if (p == end) + { + size_t oldsize = linebuffer->size; + buffer = x2realloc (buffer, &linebuffer->size); + p = buffer + oldsize; + linebuffer->buffer = buffer; + end = buffer + linebuffer->size; + } + *p++ = c; + } + while (c != '\n'); + + linebuffer->length = p - buffer; + return linebuffer; +} + +/* Free the buffer that was allocated for linebuffer LINEBUFFER. */ + +void +freebuffer (struct linebuffer *linebuffer) +{ + free (linebuffer->buffer); +} |