The idea is to provide a more or less drop in replacement for readline to read from zlib/gzip streams. Take the opportunity to replace malloc with talloc. --- util/Makefile.local | 2 +- util/zlib-extra.c | 59 +++++++++++++++++++++++++++++++++++++++++++++++++++++ util/zlib-extra.h | 10 +++++++++ 3 files changed, 70 insertions(+), 1 deletion(-) create mode 100644 util/zlib-extra.c create mode 100644 util/zlib-extra.h diff --git a/util/Makefile.local b/util/Makefile.local index 29c0ce6..e2a5b65 100644 --- a/util/Makefile.local +++ b/util/Makefile.local @@ -4,7 +4,7 @@ dir := util extra_cflags += -I$(srcdir)/$(dir) libutil_c_srcs := $(dir)/xutil.c $(dir)/error_util.c $(dir)/hex-escape.c \ - $(dir)/string-util.c $(dir)/talloc-extra.c + $(dir)/string-util.c $(dir)/talloc-extra.c $(dir)/zlib-extra.c libutil_modules := $(libutil_c_srcs:.c=.o) diff --git a/util/zlib-extra.c b/util/zlib-extra.c new file mode 100644 index 0000000..cda369f --- /dev/null +++ b/util/zlib-extra.c @@ -0,0 +1,59 @@ +/* zlib-extra.c - Extra or enhanced routines for compressed I/O. + * + * Copyright (c) 2014 David Bremner + * + * 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 http://www.gnu.org/licenses/ . + * + * Author: David Bremner <david@tethera.net> + */ + +#include "zlib-extra.h" +#include <talloc.h> +#include <stdio.h> +#include <string.h> + +/* mimic POSIX/glibc getline, but on a zlib gzFile stream, and using talloc */ +ssize_t +gzgetline (void *ctx, char **lineptr, size_t *n, gzFile stream) { + + size_t len=*n; + char *buf = *lineptr; + size_t offset = 0; + + if (len == 0 || buf == NULL) { + /* XXX arbitrary choice of initial size */ + len = BUFSIZ; + buf = talloc_size (ctx, len); + } + + while (1) { + + if (!gzgets (stream, buf + offset, len)) + return -1; + + /* XXX wasted effort re-counting length of whole line */ + offset = strlen (buf); + + if ( buf[offset-1] == '\n' ) + break; + + len *= 2; + buf = talloc_realloc (ctx, buf, char, len); + + } + + *lineptr = buf; + *n = len; + return offset; +} diff --git a/util/zlib-extra.h b/util/zlib-extra.h new file mode 100644 index 0000000..c18480f --- /dev/null +++ b/util/zlib-extra.h @@ -0,0 +1,10 @@ +#ifndef _ZLIB_EXTRA_H +#define _ZLIB_EXTRA_H + +#include <zlib.h> + +/* Like getline, but read from a gzFile. Allocation is with talloc */ +ssize_t +gzgetline (void *ctx, char **lineptr, size_t *n, gzFile stream); + +#endif -- 1.9.0