Switch to using libarchive from libtar for cpack and cmake -E tar

This allows for a built in bzip and zip capability, so external tools
will not be needed for these packagers.  The cmake -E tar xf should be
able to handle all compression types now as well.

1 files changed, 1241 insertions, 0 deletions

diff --git a/Utilities/cmlibarchive/libarchive/archive_read.c b/Utilities/cmlibarchive/libarchive/archive_read.c
new file mode 100644
index 0000000..cd4416c
--- /dev/null
+++ b/Utilities/cmlibarchive/libarchive/archive_read.c
@@ -0,0 +1,1241 @@
+/*-
+ * Copyright (c) 2003-2007 Tim Kientzle
+ * All rights reserved.
+ *
+ * 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.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR(S) ``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 AUTHOR(S) 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.
+ */
+
+/*
+ * This file contains the "essential" portions of the read API, that
+ * is, stuff that will probably always be used by any client that
+ * actually needs to read an archive.  Optional pieces have been, as
+ * far as possible, separated out into separate files to avoid
+ * needlessly bloating statically-linked clients.
+ */
+
+#include "archive_platform.h"
+__FBSDID("$FreeBSD: src/lib/libarchive/archive_read.c,v 1.39 2008/12/06 06:45:15 kientzle Exp $");
+
+#ifdef HAVE_ERRNO_H
+#include <errno.h>
+#endif
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+#include <stdlib.h>
+#endif
+#ifdef HAVE_STRING_H
+#include <string.h>
+#endif
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#include "archive.h"
+#include "archive_entry.h"
+#include "archive_private.h"
+#include "archive_read_private.h"
+
+#define minimum(a, b) (a < b ? a : b)
+
+static int  build_stream(struct archive_read *);
+static int  choose_format(struct archive_read *);
+static struct archive_vtable *archive_read_vtable(void);
+static int  _archive_read_close(struct archive *);
+static int  _archive_read_finish(struct archive *);
+
+static struct archive_vtable *
+archive_read_vtable(void)
+{
+    static struct archive_vtable av;
+    static int inited = 0;
+
+    if (!inited) {
+        av.archive_finish = _archive_read_finish;
+        av.archive_close = _archive_read_close;
+    }
+    return (&av);
+}
+
+/*
+ * Allocate, initialize and return a struct archive object.
+ */
+struct archive *
+archive_read_new(void)
+{
+    struct archive_read *a;
+
+    a = (struct archive_read *)malloc(sizeof(*a));
+    if (a == NULL)
+        return (NULL);
+    memset(a, 0, sizeof(*a));
+    a->archive.magic = ARCHIVE_READ_MAGIC;
+
+    a->archive.state = ARCHIVE_STATE_NEW;
+    a->entry = archive_entry_new();
+    a->archive.vtable = archive_read_vtable();
+
+    return (&a->archive);
+}
+
+/*
+ * Record the do-not-extract-to file. This belongs in archive_read_extract.c.
+ */
+void
+archive_read_extract_set_skip_file(struct archive *_a, dev_t d, ino_t i)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_ANY,
+        "archive_read_extract_set_skip_file");
+    a->skip_file_dev = d;
+    a->skip_file_ino = i;
+}
+
+/*
+ * Set read options for the format.
+ */
+int
+archive_read_set_format_options(struct archive *_a, const char *s)
+{
+    struct archive_read *a;
+    struct archive_format_descriptor *format;
+    char key[64], val[64];
+    char *valp;
+    size_t i;
+    int len, r;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "archive_read_set_format_options");
+
+    if (s == NULL || *s == '\0')
+        return (ARCHIVE_OK);
+    a = (struct archive_read *)_a;
+    __archive_check_magic(&a->archive, ARCHIVE_READ_MAGIC,
+        ARCHIVE_STATE_NEW, "archive_read_set_format_options");
+    len = 0;
+    for (i = 0; i < sizeof(a->formats)/sizeof(a->formats[0]); i++) {
+        format = &a->formats[i];
+        if (format == NULL || format->options == NULL ||
+            format->name == NULL)
+            /* This format does not support option. */
+            continue;
+
+        while ((len = __archive_parse_options(s, format->name,
+            sizeof(key), key, sizeof(val), val)) > 0) {
+            valp = val[0] == '\0' ? NULL : val;
+            a->format = format;
+            r = format->options(a, key, valp);
+            a->format = NULL;
+            if (r == ARCHIVE_FATAL)
+                return (r);
+            s += len;
+        }
+    }
+    if (len < 0) {
+        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+            "Illegal format options.");
+        return (ARCHIVE_WARN);
+    }
+    return (ARCHIVE_OK);
+}
+
+/*
+ * Set read options for the filter.
+ */
+int
+archive_read_set_filter_options(struct archive *_a, const char *s)
+{
+    struct archive_read *a;
+    struct archive_read_filter *filter;
+    struct archive_read_filter_bidder *bidder;
+    char key[64], val[64];
+    int len, r;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "archive_read_set_filter_options");
+
+    if (s == NULL || *s == '\0')
+        return (ARCHIVE_OK);
+    a = (struct archive_read *)_a;
+    __archive_check_magic(&a->archive, ARCHIVE_READ_MAGIC,
+        ARCHIVE_STATE_NEW, "archive_read_set_filter_options");
+    filter = a->filter;
+    len = 0;
+    for (filter = a->filter; filter != NULL; filter = filter->upstream) {
+        bidder = filter->bidder;
+        if (bidder == NULL)
+            continue;
+        if (bidder->options == NULL)
+            /* This bidder does not support option */
+            continue;
+        while ((len = __archive_parse_options(s, filter->name,
+            sizeof(key), key, sizeof(val), val)) > 0) {
+            if (val[0] == '\0')
+                r = bidder->options(bidder, key, NULL);
+            else
+                r = bidder->options(bidder, key, val);
+            if (r == ARCHIVE_FATAL)
+                return (r);
+            s += len;
+        }
+    }
+    if (len < 0) {
+        archive_set_error(&a->archive, ARCHIVE_ERRNO_MISC,
+            "Illegal format options.");
+        return (ARCHIVE_WARN);
+    }
+    return (ARCHIVE_OK);
+}
+
+/*
+ * Set read options for the format and the filter.
+ */
+int
+archive_read_set_options(struct archive *_a, const char *s)
+{
+    int r;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "archive_read_set_options");
+    archive_clear_error(_a);
+
+    r = archive_read_set_format_options(_a, s);
+    if (r != ARCHIVE_OK)
+        return (r);
+    r = archive_read_set_filter_options(_a, s);
+    if (r != ARCHIVE_OK)
+        return (r);
+    return (ARCHIVE_OK);
+}
+
+/*
+ * Open the archive
+ */
+int
+archive_read_open(struct archive *a, void *client_data,
+    archive_open_callback *client_opener, archive_read_callback *client_reader,
+    archive_close_callback *client_closer)
+{
+    /* Old archive_read_open() is just a thin shell around
+     * archive_read_open2. */
+    return archive_read_open2(a, client_data, client_opener,
+        client_reader, NULL, client_closer);
+}
+
+static ssize_t
+client_read_proxy(struct archive_read_filter *self, const void **buff)
+{
+    ssize_t r;
+    r = (self->archive->client.reader)(&self->archive->archive,
+        self->data, buff);
+    self->archive->archive.raw_position += r;
+    return (r);
+}
+
+static int64_t
+client_skip_proxy(struct archive_read_filter *self, int64_t request)
+{
+    int64_t ask, get, total;
+    /* Limit our maximum seek request to 1GB on platforms
+    * with 32-bit off_t (such as Windows). */
+    int64_t skip_limit = ((int64_t)1) << (sizeof(off_t) * 8 - 2);
+
+    if (self->archive->client.skipper == NULL)
+        return (0);
+    total = 0;
+    for (;;) {
+        ask = request;
+        if (ask > skip_limit)
+            ask = skip_limit;
+        get = (self->archive->client.skipper)(&self->archive->archive,
+            self->data, ask);
+        if (get == 0)
+            return (total);
+        request -= get;
+        self->archive->archive.raw_position += get;
+        total += get;
+    }
+}
+
+static int
+client_close_proxy(struct archive_read_filter *self)
+{
+    int r = ARCHIVE_OK;
+
+    if (self->archive->client.closer != NULL)
+        r = (self->archive->client.closer)((struct archive *)self->archive,
+            self->data);
+    self->data = NULL;
+    return (r);
+}
+
+
+int
+archive_read_open2(struct archive *_a, void *client_data,
+    archive_open_callback *client_opener,
+    archive_read_callback *client_reader,
+    archive_skip_callback *client_skipper,
+    archive_close_callback *client_closer)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    struct archive_read_filter *filter;
+    int e;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "archive_read_open");
+    archive_clear_error(&a->archive);
+
+    if (client_reader == NULL)
+        __archive_errx(1,
+            "No reader function provided to archive_read_open");
+
+    /* Open data source. */
+    if (client_opener != NULL) {
+        e =(client_opener)(&a->archive, client_data);
+        if (e != 0) {
+            /* If the open failed, call the closer to clean up. */
+            if (client_closer)
+                (client_closer)(&a->archive, client_data);
+            return (e);
+        }
+    }
+
+    /* Save the client functions and mock up the initial source. */
+    a->client.reader = client_reader;
+    a->client.skipper = client_skipper;
+    a->client.closer = client_closer;
+
+    filter = calloc(1, sizeof(*filter));
+    if (filter == NULL)
+        return (ARCHIVE_FATAL);
+    filter->bidder = NULL;
+    filter->upstream = NULL;
+    filter->archive = a;
+    filter->data = client_data;
+    filter->read = client_read_proxy;
+    filter->skip = client_skip_proxy;
+    filter->close = client_close_proxy;
+    filter->name = "none";
+    filter->code = ARCHIVE_COMPRESSION_NONE;
+    a->filter = filter;
+
+    /* Build out the input pipeline. */
+    e = build_stream(a);
+    if (e == ARCHIVE_OK)
+        a->archive.state = ARCHIVE_STATE_HEADER;
+
+    return (e);
+}
+
+/*
+ * Allow each registered stream transform to bid on whether
+ * it wants to handle this stream.  Repeat until we've finished
+ * building the pipeline.
+ */
+static int
+build_stream(struct archive_read *a)
+{
+    int number_bidders, i, bid, best_bid;
+    struct archive_read_filter_bidder *bidder, *best_bidder;
+    struct archive_read_filter *filter;
+    ssize_t avail;
+    int r;
+
+    for (;;) {
+        number_bidders = sizeof(a->bidders) / sizeof(a->bidders[0]);
+
+        best_bid = 0;
+        best_bidder = NULL;
+
+        bidder = a->bidders;
+        for (i = 0; i < number_bidders; i++, bidder++) {
+            if (bidder->bid != NULL) {
+                bid = (bidder->bid)(bidder, a->filter);
+                if (bid > best_bid) {
+                    best_bid = bid;
+                    best_bidder = bidder;
+                }
+            }
+        }
+
+        /* If no bidder, we're done. */
+        if (best_bidder == NULL) {
+            a->archive.compression_name = a->filter->name;
+            a->archive.compression_code = a->filter->code;
+            return (ARCHIVE_OK);
+        }
+
+        filter
+            = (struct archive_read_filter *)calloc(1, sizeof(*filter));
+        if (filter == NULL)
+            return (ARCHIVE_FATAL);
+        filter->bidder = best_bidder;
+        filter->archive = a;
+        filter->upstream = a->filter;
+        r = (best_bidder->init)(filter);
+        if (r != ARCHIVE_OK) {
+            free(filter);
+            return (r);
+        }
+        /* Verify the filter by asking it for some data. */
+        __archive_read_filter_ahead(filter, 1, &avail);
+        if (avail < 0) {
+            /* If the read failed, bail out now. */
+            free(filter);
+            return (avail);
+        }
+        a->filter = filter;
+    }
+}
+
+/*
+ * Read header of next entry.
+ */
+int
+archive_read_next_header2(struct archive *_a, struct archive_entry *entry)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    int slot, ret;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC,
+        ARCHIVE_STATE_HEADER | ARCHIVE_STATE_DATA,
+        "archive_read_next_header");
+
+    ++_a->file_count;
+    archive_entry_clear(entry);
+    archive_clear_error(&a->archive);
+
+    /*
+     * If no format has yet been chosen, choose one.
+     */
+    if (a->format == NULL) {
+        slot = choose_format(a);
+        if (slot < 0) {
+            a->archive.state = ARCHIVE_STATE_FATAL;
+            return (ARCHIVE_FATAL);
+        }
+        a->format = &(a->formats[slot]);
+    }
+
+    /*
+     * If client didn't consume entire data, skip any remainder
+     * (This is especially important for GNU incremental directories.)
+     */
+    if (a->archive.state == ARCHIVE_STATE_DATA) {
+        ret = archive_read_data_skip(&a->archive);
+        if (ret == ARCHIVE_EOF) {
+            archive_set_error(&a->archive, EIO, "Premature end-of-file.");
+            a->archive.state = ARCHIVE_STATE_FATAL;
+            return (ARCHIVE_FATAL);
+        }
+        if (ret != ARCHIVE_OK)
+            return (ret);
+    }
+
+    /* Record start-of-header. */
+    a->header_position = a->archive.file_position;
+
+    ret = (a->format->read_header)(a, entry);
+
+    /*
+     * EOF and FATAL are persistent at this layer.  By
+     * modifying the state, we guarantee that future calls to
+     * read a header or read data will fail.
+     */
+    switch (ret) {
+    case ARCHIVE_EOF:
+        a->archive.state = ARCHIVE_STATE_EOF;
+        break;
+    case ARCHIVE_OK:
+        a->archive.state = ARCHIVE_STATE_DATA;
+        break;
+    case ARCHIVE_WARN:
+        a->archive.state = ARCHIVE_STATE_DATA;
+        break;
+    case ARCHIVE_RETRY:
+        break;
+    case ARCHIVE_FATAL:
+        a->archive.state = ARCHIVE_STATE_FATAL;
+        break;
+    }
+
+    a->read_data_output_offset = 0;
+    a->read_data_remaining = 0;
+    return (ret);
+}
+
+int
+archive_read_next_header(struct archive *_a, struct archive_entry **entryp)
+{
+    int ret;
+    struct archive_read *a = (struct archive_read *)_a;
+    *entryp = NULL;
+    ret = archive_read_next_header2(_a, a->entry);
+    *entryp = a->entry;
+    return ret;
+}
+
+/*
+ * Allow each registered format to bid on whether it wants to handle
+ * the next entry.  Return index of winning bidder.
+ */
+static int
+choose_format(struct archive_read *a)
+{
+    int slots;
+    int i;
+    int bid, best_bid;
+    int best_bid_slot;
+
+    slots = sizeof(a->formats) / sizeof(a->formats[0]);
+    best_bid = -1;
+    best_bid_slot = -1;
+
+    /* Set up a->format and a->pformat_data for convenience of bidders. */
+    a->format = &(a->formats[0]);
+    for (i = 0; i < slots; i++, a->format++) {
+        if (a->format->bid) {
+            bid = (a->format->bid)(a);
+            if (bid == ARCHIVE_FATAL)
+                return (ARCHIVE_FATAL);
+            if ((bid > best_bid) || (best_bid_slot < 0)) {
+                best_bid = bid;
+                best_bid_slot = i;
+            }
+        }
+    }
+
+    /*
+     * There were no bidders; this is a serious programmer error
+     * and demands a quick and definitive abort.
+     */
+    if (best_bid_slot < 0)
+        __archive_errx(1, "No formats were registered; you must "
+            "invoke at least one archive_read_support_format_XXX "
+            "function in order to successfully read an archive.");
+
+    /*
+     * There were bidders, but no non-zero bids; this means we
+     * can't support this stream.
+     */
+    if (best_bid < 1) {
+        archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
+            "Unrecognized archive format");
+        return (ARCHIVE_FATAL);
+    }
+
+    return (best_bid_slot);
+}
+
+/*
+ * Return the file offset (within the uncompressed data stream) where
+ * the last header started.
+ */
+int64_t
+archive_read_header_position(struct archive *_a)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC,
+        ARCHIVE_STATE_ANY, "archive_read_header_position");
+    return (a->header_position);
+}
+
+/*
+ * Read data from an archive entry, using a read(2)-style interface.
+ * This is a convenience routine that just calls
+ * archive_read_data_block and copies the results into the client
+ * buffer, filling any gaps with zero bytes.  Clients using this
+ * API can be completely ignorant of sparse-file issues; sparse files
+ * will simply be padded with nulls.
+ *
+ * DO NOT intermingle calls to this function and archive_read_data_block
+ * to read a single entry body.
+ */
+ssize_t
+archive_read_data(struct archive *_a, void *buff, size_t s)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    char    *dest;
+    const void *read_buf;
+    size_t   bytes_read;
+    size_t   len;
+    int  r;
+
+    bytes_read = 0;
+    dest = (char *)buff;
+
+    while (s > 0) {
+        if (a->read_data_remaining == 0) {
+            read_buf = a->read_data_block;
+            r = archive_read_data_block(&a->archive, &read_buf,
+                &a->read_data_remaining, &a->read_data_offset);
+            a->read_data_block = read_buf;
+            if (r == ARCHIVE_EOF)
+                return (bytes_read);
+            /*
+             * Error codes are all negative, so the status
+             * return here cannot be confused with a valid
+             * byte count.  (ARCHIVE_OK is zero.)
+             */
+            if (r < ARCHIVE_OK)
+                return (r);
+        }
+
+        if (a->read_data_offset < a->read_data_output_offset) {
+            archive_set_error(&a->archive, ARCHIVE_ERRNO_FILE_FORMAT,
+                "Encountered out-of-order sparse blocks");
+            return (ARCHIVE_RETRY);
+        }
+
+        /* Compute the amount of zero padding needed. */
+        if (a->read_data_output_offset + (off_t)s <
+            a->read_data_offset) {
+            len = s;
+        } else if (a->read_data_output_offset <
+            a->read_data_offset) {
+            len = a->read_data_offset -
+                a->read_data_output_offset;
+        } else
+            len = 0;
+
+        /* Add zeroes. */
+        memset(dest, 0, len);
+        s -= len;
+        a->read_data_output_offset += len;
+        dest += len;
+        bytes_read += len;
+
+        /* Copy data if there is any space left. */
+        if (s > 0) {
+            len = a->read_data_remaining;
+            if (len > s)
+                len = s;
+            memcpy(dest, a->read_data_block, len);
+            s -= len;
+            a->read_data_block += len;
+            a->read_data_remaining -= len;
+            a->read_data_output_offset += len;
+            a->read_data_offset += len;
+            dest += len;
+            bytes_read += len;
+        }
+    }
+    return (bytes_read);
+}
+
+#if ARCHIVE_API_VERSION < 3
+/*
+ * Obsolete function provided for compatibility only.  Note that the API
+ * of this function doesn't allow the caller to detect if the remaining
+ * data from the archive entry is shorter than the buffer provided, or
+ * even if an error occurred while reading data.
+ */
+int
+archive_read_data_into_buffer(struct archive *a, void *d, ssize_t len)
+{
+
+    archive_read_data(a, d, len);
+    return (ARCHIVE_OK);
+}
+#endif
+
+/*
+ * Skip over all remaining data in this entry.
+ */
+int
+archive_read_data_skip(struct archive *_a)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    int r;
+    const void *buff;
+    size_t size;
+    off_t offset;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_DATA,
+        "archive_read_data_skip");
+
+    if (a->format->read_data_skip != NULL)
+        r = (a->format->read_data_skip)(a);
+    else {
+        while ((r = archive_read_data_block(&a->archive,
+                &buff, &size, &offset))
+            == ARCHIVE_OK)
+            ;
+    }
+
+    if (r == ARCHIVE_EOF)
+        r = ARCHIVE_OK;
+
+    a->archive.state = ARCHIVE_STATE_HEADER;
+    return (r);
+}
+
+/*
+ * Read the next block of entry data from the archive.
+ * This is a zero-copy interface; the client receives a pointer,
+ * size, and file offset of the next available block of data.
+ *
+ * Returns ARCHIVE_OK if the operation is successful, ARCHIVE_EOF if
+ * the end of entry is encountered.
+ */
+int
+archive_read_data_block(struct archive *_a,
+    const void **buff, size_t *size, off_t *offset)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_DATA,
+        "archive_read_data_block");
+
+    if (a->format->read_data == NULL) {
+        archive_set_error(&a->archive, ARCHIVE_ERRNO_PROGRAMMER,
+            "Internal error: "
+            "No format_read_data_block function registered");
+        return (ARCHIVE_FATAL);
+    }
+
+    return (a->format->read_data)(a, buff, size, offset);
+}
+
+/*
+ * Close the file and release most resources.
+ *
+ * Be careful: client might just call read_new and then read_finish.
+ * Don't assume we actually read anything or performed any non-trivial
+ * initialization.
+ */
+static int
+_archive_read_close(struct archive *_a)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    int r = ARCHIVE_OK, r1 = ARCHIVE_OK;
+    size_t i, n;
+
+    __archive_check_magic(&a->archive, ARCHIVE_READ_MAGIC,
+        ARCHIVE_STATE_ANY, "archive_read_close");
+    archive_clear_error(&a->archive);
+    a->archive.state = ARCHIVE_STATE_CLOSED;
+
+
+    /* Call cleanup functions registered by optional components. */
+    if (a->cleanup_archive_extract != NULL)
+        r = (a->cleanup_archive_extract)(a);
+
+    /* TODO: Clean up the formatters. */
+
+    /* Clean up the filter pipeline. */
+    while (a->filter != NULL) {
+        struct archive_read_filter *t = a->filter->upstream;
+        if (a->filter->close != NULL) {
+            r1 = (a->filter->close)(a->filter);
+            if (r1 < r)
+                r = r1;
+        }
+        free(a->filter->buffer);
+        free(a->filter);
+        a->filter = t;
+    }
+
+    /* Release the bidder objects. */
+    n = sizeof(a->bidders)/sizeof(a->bidders[0]);
+    for (i = 0; i < n; i++) {
+        if (a->bidders[i].free != NULL) {
+            r1 = (a->bidders[i].free)(&a->bidders[i]);
+            if (r1 < r)
+                r = r1;
+        }
+    }
+
+    return (r);
+}
+
+/*
+ * Release memory and other resources.
+ */
+int
+_archive_read_finish(struct archive *_a)
+{
+    struct archive_read *a = (struct archive_read *)_a;
+    int i;
+    int slots;
+    int r = ARCHIVE_OK;
+
+    __archive_check_magic(_a, ARCHIVE_READ_MAGIC, ARCHIVE_STATE_ANY,
+        "archive_read_finish");
+    if (a->archive.state != ARCHIVE_STATE_CLOSED)
+        r = archive_read_close(&a->archive);
+
+    /* Cleanup format-specific data. */
+    slots = sizeof(a->formats) / sizeof(a->formats[0]);
+    for (i = 0; i < slots; i++) {
+        a->format = &(a->formats[i]);
+        if (a->formats[i].cleanup)
+            (a->formats[i].cleanup)(a);
+    }
+
+    archive_string_free(&a->archive.error_string);
+    if (a->entry)
+        archive_entry_free(a->entry);
+    a->archive.magic = 0;
+    free(a);
+#if ARCHIVE_API_VERSION > 1
+    return (r);
+#endif
+}
+
+/*
+ * Used internally by read format handlers to register their bid and
+ * initialization functions.
+ */
+int
+__archive_read_register_format(struct archive_read *a,
+    void *format_data,
+    const char *name,
+    int (*bid)(struct archive_read *),
+    int (*options)(struct archive_read *, const char *, const char *),
+    int (*read_header)(struct archive_read *, struct archive_entry *),
+    int (*read_data)(struct archive_read *, const void **, size_t *, off_t *),
+    int (*read_data_skip)(struct archive_read *),
+    int (*cleanup)(struct archive_read *))
+{
+    int i, number_slots;
+
+    __archive_check_magic(&a->archive,
+        ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "__archive_read_register_format");
+
+    number_slots = sizeof(a->formats) / sizeof(a->formats[0]);
+
+    for (i = 0; i < number_slots; i++) {
+        if (a->formats[i].bid == bid)
+            return (ARCHIVE_WARN); /* We've already installed */
+        if (a->formats[i].bid == NULL) {
+            a->formats[i].bid = bid;
+            a->formats[i].options = options;
+            a->formats[i].read_header = read_header;
+            a->formats[i].read_data = read_data;
+            a->formats[i].read_data_skip = read_data_skip;
+            a->formats[i].cleanup = cleanup;
+            a->formats[i].data = format_data;
+            a->formats[i].name = name;
+            return (ARCHIVE_OK);
+        }
+    }
+
+    __archive_errx(1, "Not enough slots for format registration");
+    return (ARCHIVE_FATAL); /* Never actually called. */
+}
+
+/*
+ * Used internally by decompression routines to register their bid and
+ * initialization functions.
+ */
+struct archive_read_filter_bidder *
+__archive_read_get_bidder(struct archive_read *a)
+{
+    int i, number_slots;
+
+    __archive_check_magic(&a->archive,
+        ARCHIVE_READ_MAGIC, ARCHIVE_STATE_NEW,
+        "__archive_read_get_bidder");
+
+    number_slots = sizeof(a->bidders) / sizeof(a->bidders[0]);
+
+    for (i = 0; i < number_slots; i++) {
+        if (a->bidders[i].bid == NULL) {
+            memset(a->bidders + i, 0, sizeof(a->bidders[0]));
+            return (a->bidders + i);
+        }
+    }
+
+    __archive_errx(1, "Not enough slots for compression registration");
+    return (NULL); /* Never actually executed. */
+}
+
+/*
+ * The next three functions comprise the peek/consume internal I/O
+ * system used by archive format readers.  This system allows fairly
+ * flexible read-ahead and allows the I/O code to operate in a
+ * zero-copy manner most of the time.
+ *
+ * In the ideal case, filters generate blocks of data
+ * and __archive_read_ahead() just returns pointers directly into
+ * those blocks.  Then __archive_read_consume() just bumps those
+ * pointers.  Only if your request would span blocks does the I/O
+ * layer use a copy buffer to provide you with a contiguous block of
+ * data.  The __archive_read_skip() is an optimization; it scans ahead
+ * very quickly (it usually translates into a seek() operation if
+ * you're reading uncompressed disk files).
+ *
+ * A couple of useful idioms:
+ *  * "I just want some data."  Ask for 1 byte and pay attention to
+ *    the "number of bytes available" from __archive_read_ahead().
+ *    You can consume more than you asked for; you just can't consume
+ *    more than is available.  If you consume everything that's
+ *    immediately available, the next read_ahead() call will pull
+ *    the next block.
+ *  * "I want to output a large block of data."  As above, ask for 1 byte,
+ *    emit all that's available (up to whatever limit you have), then
+ *    repeat until you're done.
+ *  * "I want to peek ahead by a large amount."  Ask for 4k or so, then
+ *    double and repeat until you get an error or have enough.  Note
+ *    that the I/O layer will likely end up expanding its copy buffer
+ *    to fit your request, so use this technique cautiously.  This
+ *    technique is used, for example, by some of the format tasting
+ *    code that has uncertain look-ahead needs.
+ *
+ * TODO: Someday, provide a more generic __archive_read_seek() for
+ * those cases where it's useful.  This is tricky because there are lots
+ * of cases where seek() is not available (reading gzip data from a
+ * network socket, for instance), so there needs to be a good way to
+ * communicate whether seek() is available and users of that interface
+ * need to use non-seeking strategies whenever seek() is not available.
+ */
+
+/*
+ * Looks ahead in the input stream:
+ *  * If 'avail' pointer is provided, that returns number of bytes available
+ *    in the current buffer, which may be much larger than requested.
+ *  * If end-of-file, *avail gets set to zero.
+ *  * If error, *avail gets error code.
+ *  * If request can be met, returns pointer to data, returns NULL
+ *    if request is not met.
+ *
+ * Note: If you just want "some data", ask for 1 byte and pay attention
+ * to *avail, which will have the actual amount available.  If you
+ * know exactly how many bytes you need, just ask for that and treat
+ * a NULL return as an error.
+ *
+ * Important:  This does NOT move the file pointer.  See
+ * __archive_read_consume() below.
+ */
+
+/*
+ * This is tricky.  We need to provide our clients with pointers to
+ * contiguous blocks of memory but we want to avoid copying whenever
+ * possible.
+ *
+ * Mostly, this code returns pointers directly into the block of data
+ * provided by the client_read routine.  It can do this unless the
+ * request would split across blocks.  In that case, we have to copy
+ * into an internal buffer to combine reads.
+ */
+const void *
+__archive_read_ahead(struct archive_read *a, size_t min, ssize_t *avail)
+{
+    return (__archive_read_filter_ahead(a->filter, min, avail));
+}
+
+const void *
+__archive_read_filter_ahead(struct archive_read_filter *filter,
+    size_t min, ssize_t *avail)
+{
+    ssize_t bytes_read;
+    size_t tocopy;
+
+    if (filter->fatal) {
+        if (avail)
+            *avail = ARCHIVE_FATAL;
+        return (NULL);
+    }
+
+    /*
+     * Keep pulling more data until we can satisfy the request.
+     */
+    for (;;) {
+
+        /*
+         * If we can satisfy from the copy buffer (and the
+         * copy buffer isn't empty), we're done.  In particular,
+         * note that min == 0 is a perfectly well-defined
+         * request.
+         */
+        if (filter->avail >= min && filter->avail > 0) {
+            if (avail != NULL)
+                *avail = filter->avail;
+            return (filter->next);
+        }
+
+        /*
+         * We can satisfy directly from client buffer if everything
+         * currently in the copy buffer is still in the client buffer.
+         */
+        if (filter->client_total >= filter->client_avail + filter->avail
+            && filter->client_avail + filter->avail >= min) {
+            /* "Roll back" to client buffer. */
+            filter->client_avail += filter->avail;
+            filter->client_next -= filter->avail;
+            /* Copy buffer is now empty. */
+            filter->avail = 0;
+            filter->next = filter->buffer;
+            /* Return data from client buffer. */
+            if (avail != NULL)
+                *avail = filter->client_avail;
+            return (filter->client_next);
+        }
+
+        /* Move data forward in copy buffer if necessary. */
+        if (filter->next > filter->buffer &&
+            filter->next + min > filter->buffer + filter->buffer_size) {
+            if (filter->avail > 0)
+                memmove(filter->buffer, filter->next, filter->avail);
+            filter->next = filter->buffer;
+        }
+
+        /* If we've used up the client data, get more. */
+        if (filter->client_avail <= 0) {
+            if (filter->end_of_file) {
+                if (avail != NULL)
+                    *avail = 0;
+                return (NULL);
+            }
+            bytes_read = (filter->read)(filter,
+                &filter->client_buff);
+            if (bytes_read < 0) {       /* Read error. */
+                filter->client_total = filter->client_avail = 0;
+                filter->client_next = filter->client_buff = NULL;
+                filter->fatal = 1;
+                if (avail != NULL)
+                    *avail = ARCHIVE_FATAL;
+                return (NULL);
+            }
+            if (bytes_read == 0) {  /* Premature end-of-file. */
+                filter->client_total = filter->client_avail = 0;
+                filter->client_next = filter->client_buff = NULL;
+                filter->end_of_file = 1;
+                /* Return whatever we do have. */
+                if (avail != NULL)
+                    *avail = filter->avail;
+                return (NULL);
+            }
+            filter->position += bytes_read;
+            filter->client_total = bytes_read;
+            filter->client_avail = filter->client_total;
+            filter->client_next = filter->client_buff;
+        }
+        else
+        {
+            /*
+             * We can't satisfy the request from the copy
+             * buffer or the existing client data, so we
+             * need to copy more client data over to the
+             * copy buffer.
+             */
+
+            /* Ensure the buffer is big enough. */
+            if (min > filter->buffer_size) {
+                size_t s, t;
+                char *p;
+
+                /* Double the buffer; watch for overflow. */
+                s = t = filter->buffer_size;
+                if (s == 0)
+                    s = min;
+                while (s < min) {
+                    t *= 2;
+                    if (t <= s) { /* Integer overflow! */
+                        archive_set_error(
+                            &filter->archive->archive,
+                            ENOMEM,
+                            "Unable to allocate copy buffer");
+                        filter->fatal = 1;
+                        if (avail != NULL)
+                            *avail = ARCHIVE_FATAL;
+                        return (NULL);
+                    }
+                    s = t;
+                }
+                /* Now s >= min, so allocate a new buffer. */
+                p = (char *)malloc(s);
+                if (p == NULL) {
+                    archive_set_error(
+                        &filter->archive->archive,
+                        ENOMEM,
+                        "Unable to allocate copy buffer");
+                    filter->fatal = 1;
+                    if (avail != NULL)
+                        *avail = ARCHIVE_FATAL;
+                    return (NULL);
+                }
+                /* Move data into newly-enlarged buffer. */
+                if (filter->avail > 0)
+                    memmove(p, filter->next, filter->avail);
+                free(filter->buffer);
+                filter->next = filter->buffer = p;
+                filter->buffer_size = s;
+            }
+
+            /* We can add client data to copy buffer. */
+            /* First estimate: copy to fill rest of buffer. */
+            tocopy = (filter->buffer + filter->buffer_size)
+                - (filter->next + filter->avail);
+            /* Don't waste time buffering more than we need to. */
+            if (tocopy + filter->avail > min)
+                tocopy = min - filter->avail;
+            /* Don't copy more than is available. */
+            if (tocopy > filter->client_avail)
+                tocopy = filter->client_avail;
+
+            memcpy(filter->next + filter->avail, filter->client_next,
+                tocopy);
+            /* Remove this data from client buffer. */
+            filter->client_next += tocopy;
+            filter->client_avail -= tocopy;
+            /* add it to copy buffer. */
+            filter->avail += tocopy;
+        }
+    }
+}
+
+/*
+ * Move the file pointer forward.  This should be called after
+ * __archive_read_ahead() returns data to you.  Don't try to move
+ * ahead by more than the amount of data available according to
+ * __archive_read_ahead().
+ */
+/*
+ * Mark the appropriate data as used.  Note that the request here will
+ * often be much smaller than the size of the previous read_ahead
+ * request.
+ */
+ssize_t
+__archive_read_consume(struct archive_read *a, size_t request)
+{
+    ssize_t r;
+    r = __archive_read_filter_consume(a->filter, request);
+    a->archive.file_position += r;
+    return (r);
+}
+
+ssize_t
+__archive_read_filter_consume(struct archive_read_filter * filter,
+    size_t request)
+{
+    if (filter->avail > 0) {
+        /* Read came from copy buffer. */
+        filter->next += request;
+        filter->avail -= request;
+    } else {
+        /* Read came from client buffer. */
+        filter->client_next += request;
+        filter->client_avail -= request;
+    }
+    return (request);
+}
+
+/*
+ * Move the file pointer ahead by an arbitrary amount.  If you're
+ * reading uncompressed data from a disk file, this will actually
+ * translate into a seek() operation.  Even in cases where seek()
+ * isn't feasible, this at least pushes the read-and-discard loop
+ * down closer to the data source.
+ */
+int64_t
+__archive_read_skip(struct archive_read *a, int64_t request)
+{
+    int64_t skipped = __archive_read_skip_lenient(a, request);
+    if (skipped == request)
+        return (skipped);
+    /* We hit EOF before we satisfied the skip request. */
+    if (skipped < 0)  // Map error code to 0 for error message below.
+        skipped = 0;
+    archive_set_error(&a->archive,
+        ARCHIVE_ERRNO_MISC,
+        "Truncated input file (needed %jd bytes, only %jd available)",
+        (intmax_t)request, (intmax_t)skipped);
+    return (ARCHIVE_FATAL);
+}
+
+int64_t
+__archive_read_skip_lenient(struct archive_read *a, int64_t request)
+{
+    int64_t skipped = __archive_read_filter_skip(a->filter, request);
+    if (skipped > 0)
+        a->archive.file_position += skipped;
+    return (skipped);
+}
+
+int64_t
+__archive_read_filter_skip(struct archive_read_filter *filter, int64_t request)
+{
+    int64_t bytes_skipped, total_bytes_skipped = 0;
+    size_t min;
+
+    if (filter->fatal)
+        return (-1);
+    /*
+     * If there is data in the buffers already, use that first.
+     */
+    if (filter->avail > 0) {
+        min = minimum(request, (off_t)filter->avail);
+        bytes_skipped = __archive_read_filter_consume(filter, min);
+        request -= bytes_skipped;
+        total_bytes_skipped += bytes_skipped;
+    }
+    if (filter->client_avail > 0) {
+        min = minimum(request, (int64_t)filter->client_avail);
+        bytes_skipped = __archive_read_filter_consume(filter, min);
+        request -= bytes_skipped;
+        total_bytes_skipped += bytes_skipped;
+    }
+    if (request == 0)
+        return (total_bytes_skipped);
+    /*
+     * If a client_skipper was provided, try that first.
+     */
+#if ARCHIVE_API_VERSION < 2
+    if ((filter->skip != NULL) && (request < SSIZE_MAX)) {
+#else
+    if (filter->skip != NULL) {
+#endif
+        bytes_skipped = (filter->skip)(filter, request);
+        if (bytes_skipped < 0) {    /* error */
+            filter->client_total = filter->client_avail = 0;
+            filter->client_next = filter->client_buff = NULL;
+            filter->fatal = 1;
+            return (bytes_skipped);
+        }
+        total_bytes_skipped += bytes_skipped;
+        request -= bytes_skipped;
+        filter->client_next = filter->client_buff;
+        filter->client_avail = filter->client_total = 0;
+    }
+    /*
+     * Note that client_skipper will usually not satisfy the
+     * full request (due to low-level blocking concerns),
+     * so even if client_skipper is provided, we may still
+     * have to use ordinary reads to finish out the request.
+     */
+    while (request > 0) {
+        const void* dummy_buffer;
+        ssize_t bytes_read;
+        dummy_buffer = __archive_read_filter_ahead(filter,
+            1, &bytes_read);
+        if (bytes_read < 0)
+            return (bytes_read);
+        if (bytes_read == 0) {
+            return (total_bytes_skipped);
+        }
+        min = (size_t)(minimum(bytes_read, request));
+        bytes_read = __archive_read_filter_consume(filter, min);
+        total_bytes_skipped += bytes_read;
+        request -= bytes_read;
+    }
+    return (total_bytes_skipped);
+}