New source that computes size/crc. Use it in zip_fread to verify crc.
--HG--
branch : HEAD
diff --git a/lib/zip_source_crc.c b/lib/zip_source_crc.c
new file mode 100644
index 0000000..e13141c
--- /dev/null
+++ b/lib/zip_source_crc.c
@@ -0,0 +1,142 @@
+/*
+ zip_source_crc.c -- pass-through source that calculates CRC32
+ Copyright (C) 2009 Dieter Baron and Thomas Klausner
+
+ This file is part of libzip, a library to manipulate ZIP archives.
+ The authors can be contacted at <libzip@nih.at>
+
+ Redistribution and use in source and binary forms, with or without
+ modification, are permitted provided that the following conditions
+ are met:
+ 1. Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+ 2. Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+ 3. The names of the authors may not be used to endorse or promote
+ products derived from this software without specific prior
+ written permission.
+
+ THIS SOFTWARE IS PROVIDED BY THE AUTHORS ``AS IS'' AND ANY EXPRESS
+ OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+ WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR ANY
+ DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
+ GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
+ IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
+ IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+*/
+
+
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "zipint.h"
+
+struct crc {
+ struct zip_source *src;
+ int eof;
+ zip_uint64_t size;
+ zip_uint32_t crc;
+};
+
+static zip_int64_t crc_read(void *, void *, zip_uint64_t, enum zip_source_cmd);
+
+
+
+ZIP_EXTERN struct zip_source *
+zip_source_crc(struct zip *za, struct zip_source *src)
+{
+ struct crc *ctx;
+
+ if (za == NULL || src == NULL) {
+ _zip_error_set(&za->error, ZIP_ER_INVAL, 0);
+ return NULL;
+ }
+
+ if ((ctx=(struct crc *)malloc(sizeof(*ctx))) == NULL) {
+ _zip_error_set(&za->error, ZIP_ER_MEMORY, 0);
+ return NULL;
+ }
+
+ ctx->eof = 0;
+ ctx->crc = crc32(0, NULL, 0);
+ ctx->size = 0;
+ ctx->src = src;
+
+
+ return zip_source_function(za, crc_read, ctx);
+}
+
+
+
+static zip_int64_t
+crc_read(void *_ctx, void *data, zip_uint64_t len, enum zip_source_cmd cmd)
+{
+ struct crc *ctx;
+ zip_int64_t n;
+
+ ctx = (struct crc *)_ctx;
+
+ switch (cmd) {
+ case ZIP_SOURCE_OPEN:
+ if (zip_source_call(ctx->src, data, len, cmd) < 0)
+ return -1;
+
+ return 0;
+
+ case ZIP_SOURCE_READ:
+ if (ctx->eof || len == 0)
+ return 0;
+
+ if ((n=zip_source_call(ctx->src, data, len, cmd)) < 0)
+ return -1;
+
+ if (n == 0)
+ ctx->eof = 1;
+ else {
+ ctx->size += n;
+ ctx->crc = crc32(ctx->crc, data, n);
+ }
+ return n;
+
+ case ZIP_SOURCE_CLOSE:
+ if (zip_source_call(ctx->src, data, len, cmd) < 0)
+ return -1;
+ return 0;
+
+ case ZIP_SOURCE_STAT:
+ if (zip_source_call(ctx->src, data, len, cmd) < 0)
+ return -1;
+ else {
+ struct zip_stat *st;
+
+ st = (struct zip_stat *)data;
+
+ if (ctx->eof) {
+ /* XXX: error if mismatch with what src provided? */
+ st->size = ctx->size;
+ st->crc = ctx->crc;
+ st->valid |= ZIP_STAT_SIZE|ZIP_STAT_CRC;
+ }
+ }
+ return 0;
+
+ case ZIP_SOURCE_ERROR:
+ return zip_source_call(ctx->src, data, len, cmd);
+
+ case ZIP_SOURCE_FREE:
+ zip_source_call(ctx->src, data, len, cmd);
+ free(ctx);
+ return 0;
+
+ default:
+ return zip_source_call(ctx->src, data, len, cmd);
+ }
+
+}
