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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 16:58:41 +0000
commite1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe (patch)
treef5cc731bedcac0fb7fe14d952e4581e749f8bb87 /lib/linebuffer.c
parentInitial commit. (diff)
downloadcoreutils-e1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe.tar.xz
coreutils-e1908ae95dd4c9d19ee4dfabfc8bf8a7f85943fe.zip
Adding upstream version 9.4.upstream/9.4upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'lib/linebuffer.c')
-rw-r--r--lib/linebuffer.c103
1 files changed, 103 insertions, 0 deletions
diff --git a/lib/linebuffer.c b/lib/linebuffer.c
new file mode 100644
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+++ b/lib/linebuffer.c
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+/* linebuffer.c -- read arbitrarily long lines
+
+ Copyright (C) 1986, 1991, 1998-1999, 2001, 2003-2004, 2006-2007, 2009-2023
+ 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 3 of the License, 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, see <https://www.gnu.org/licenses/>. */
+
+/* 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);
+}
+
+struct linebuffer *
+readlinebuffer (struct linebuffer *linebuffer, FILE *stream)
+{
+ return readlinebuffer_delim (linebuffer, stream, '\n');
+}
+
+/* Read an arbitrarily long line of text from STREAM into LINEBUFFER.
+ Consider lines to be terminated by DELIMITER.
+ Keep the delimiter; append DELIMITER if it's the last line of a file
+ that ends in a character other than DELIMITER. Do not NUL-terminate.
+ Therefore the stream can contain NUL bytes, and the length
+ (including the delimiter) 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_delim (struct linebuffer *linebuffer, FILE *stream,
+ char delimiter)
+{
+ 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] == delimiter)
+ break;
+ c = delimiter;
+ }
+ if (p == end)
+ {
+ idx_t oldsize = linebuffer->size;
+ buffer = xpalloc (buffer, &linebuffer->size, 1, -1, 1);
+ p = buffer + oldsize;
+ linebuffer->buffer = buffer;
+ end = buffer + linebuffer->size;
+ }
+ *p++ = c;
+ }
+ while (c != delimiter);
+
+ linebuffer->length = p - buffer;
+ return linebuffer;
+}
+
+/* Free the buffer that was allocated for linebuffer LINEBUFFER. */
+
+void
+freebuffer (struct linebuffer *linebuffer)
+{
+ free (linebuffer->buffer);
+}