diff options
Diffstat (limited to 'src/io_gunzip.c')
| -rw-r--r-- | src/io_gunzip.c | 252 |
1 files changed, 252 insertions, 0 deletions
diff --git a/src/io_gunzip.c b/src/io_gunzip.c new file mode 100644 index 0000000..b7fa9f4 --- /dev/null +++ b/src/io_gunzip.c @@ -0,0 +1,252 @@ +/* io_gunzip.c - Alpine Package Keeper (APK) + * + * Copyright (C) 2008-2011 Timo Teräs <timo.teras@iki.fi> + * All rights reserved. + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published + * by the Free Software Foundation. See http://www.gnu.org/ for details. + */ + +#include <errno.h> +#include <stdio.h> +#include <fcntl.h> +#include <unistd.h> +#include <malloc.h> +#include <zlib.h> + +#include "apk_defines.h" +#include "apk_io.h" + +struct apk_gzip_istream { + struct apk_istream is; + struct apk_istream *zis; + z_stream zs; + + apk_multipart_cb cb; + void *cbctx; + void *cbprev; + apk_blob_t cbarg; +}; + +static void gzi_get_meta(struct apk_istream *is, struct apk_file_meta *meta) +{ + struct apk_gzip_istream *gis = container_of(is, struct apk_gzip_istream, is); + apk_istream_get_meta(gis->zis, meta); +} + +static int gzi_boundary_change(struct apk_gzip_istream *gis) +{ + int r; + + r = gis->cb(gis->cbctx, gis->is.err ? APK_MPART_END : APK_MPART_BOUNDARY, gis->cbarg); + if (r > 0) r = -ECANCELED; + if (r != 0) gis->is.err = r; + return r; +} + +static ssize_t gzi_read(struct apk_istream *is, void *ptr, size_t size) +{ + struct apk_gzip_istream *gis = container_of(is, struct apk_gzip_istream, is); + int r; + + gis->zs.avail_out = size; + gis->zs.next_out = ptr; + + while (gis->zs.avail_out != 0 && gis->is.err == 0) { + if (!APK_BLOB_IS_NULL(gis->cbarg)) { + if (gzi_boundary_change(gis)) + goto ret; + gis->cbarg = APK_BLOB_NULL; + } + if (gis->zs.avail_in == 0) { + apk_blob_t blob; + + if (gis->cb != NULL && gis->cbprev != NULL && + gis->cbprev != gis->zs.next_in) { + gis->cb(gis->cbctx, APK_MPART_DATA, + APK_BLOB_PTR_LEN(gis->cbprev, + (void *)gis->zs.next_in - gis->cbprev)); + } + blob = apk_istream_get_all(gis->zis); + gis->cbprev = blob.ptr; + gis->zs.avail_in = blob.len; + gis->zs.next_in = (void *) gis->cbprev; + if (blob.len < 0) { + gis->is.err = blob.len; + goto ret; + } else if (gis->zs.avail_in == 0) { + gis->is.err = 1; + gis->cbarg = APK_BLOB_NULL; + gzi_boundary_change(gis); + goto ret; + } + } + + r = inflate(&gis->zs, Z_NO_FLUSH); + switch (r) { + case Z_STREAM_END: + /* Digest the inflated bytes */ + if (gis->zis->err && gis->zs.avail_in == 0) + gis->is.err = gis->zis->err; + if (gis->cb != NULL) { + gis->cbarg = APK_BLOB_PTR_LEN(gis->cbprev, (void *) gis->zs.next_in - gis->cbprev); + gis->cbprev = gis->zs.next_in; + } + /* If we hit end of the bitstream (not end + * of just this gzip), we need to do the + * callback here, as we won't be called again. + * For boundaries it should be postponed to not + * be called until next gzip read is started. */ + if (gis->is.err) { + gzi_boundary_change(gis); + goto ret; + } + inflateEnd(&gis->zs); + if (inflateInit2(&gis->zs, 15+32) != Z_OK) + return -ENOMEM; + if (gis->cb) goto ret; + break; + case Z_OK: + break; + default: + gis->is.err = -EIO; + break; + } + } + +ret: + return size - gis->zs.avail_out; +} + +static void gzi_close(struct apk_istream *is) +{ + struct apk_gzip_istream *gis = container_of(is, struct apk_gzip_istream, is); + + inflateEnd(&gis->zs); + apk_istream_close(gis->zis); + free(gis); +} + +static const struct apk_istream_ops gunzip_istream_ops = { + .get_meta = gzi_get_meta, + .read = gzi_read, + .close = gzi_close, +}; + +struct apk_istream *apk_istream_gunzip_mpart(struct apk_istream *is, apk_multipart_cb cb, void *ctx) +{ + struct apk_gzip_istream *gis; + + if (IS_ERR_OR_NULL(is)) return ERR_CAST(is); + + gis = malloc(sizeof(*gis) + apk_io_bufsize); + if (!gis) goto err; + + *gis = (struct apk_gzip_istream) { + .is.ops = &gunzip_istream_ops, + .is.buf = (uint8_t*)(gis + 1), + .is.buf_size = apk_io_bufsize, + .zis = is, + .cb = cb, + .cbctx = ctx, + }; + + if (inflateInit2(&gis->zs, 15+32) != Z_OK) { + free(gis); + goto err; + } + + return &gis->is; +err: + apk_istream_close(is); + return ERR_PTR(-ENOMEM); +} + +struct apk_gzip_ostream { + struct apk_ostream os; + struct apk_ostream *output; + z_stream zs; +}; + +static ssize_t gzo_write(struct apk_ostream *os, const void *ptr, size_t size) +{ + struct apk_gzip_ostream *gos = container_of(os, struct apk_gzip_ostream, os); + unsigned char buffer[1024]; + ssize_t have, r; + + gos->zs.avail_in = size; + gos->zs.next_in = (void *) ptr; + while (gos->zs.avail_in) { + gos->zs.avail_out = sizeof(buffer); + gos->zs.next_out = buffer; + r = deflate(&gos->zs, Z_NO_FLUSH); + if (r == Z_STREAM_ERROR) + return -EIO; + have = sizeof(buffer) - gos->zs.avail_out; + if (have != 0) { + r = apk_ostream_write(gos->output, buffer, have); + if (r != have) + return -EIO; + } + } + + return size; +} + +static int gzo_close(struct apk_ostream *os) +{ + struct apk_gzip_ostream *gos = container_of(os, struct apk_gzip_ostream, os); + unsigned char buffer[1024]; + size_t have; + int r, rc = 0; + + do { + gos->zs.avail_out = sizeof(buffer); + gos->zs.next_out = buffer; + r = deflate(&gos->zs, Z_FINISH); + have = sizeof(buffer) - gos->zs.avail_out; + if (apk_ostream_write(gos->output, buffer, have) != have) + rc = -EIO; + } while (r == Z_OK); + r = apk_ostream_close(gos->output); + if (r != 0) + rc = r; + + deflateEnd(&gos->zs); + free(gos); + + return rc; +} + +static const struct apk_ostream_ops gzip_ostream_ops = { + .write = gzo_write, + .close = gzo_close, +}; + +struct apk_ostream *apk_ostream_gzip(struct apk_ostream *output) +{ + struct apk_gzip_ostream *gos; + + if (IS_ERR_OR_NULL(output)) return ERR_CAST(output); + + gos = malloc(sizeof(struct apk_gzip_ostream)); + if (gos == NULL) goto err; + + *gos = (struct apk_gzip_ostream) { + .os.ops = &gzip_ostream_ops, + .output = output, + }; + + if (deflateInit2(&gos->zs, 9, Z_DEFLATED, 15 | 16, 8, + Z_DEFAULT_STRATEGY) != Z_OK) { + free(gos); + goto err; + } + + return &gos->os; +err: + apk_ostream_close(output); + return ERR_PTR(-ENOMEM); +} + |