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author | Petr Mrázek <peterix@gmail.com> | 2016-04-10 15:53:05 +0200 |
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committer | Petr Mrázek <peterix@gmail.com> | 2016-05-01 00:00:14 +0200 |
commit | b6d455a02bd338e9dc0faa09d4d8177ecd8d569a (patch) | |
tree | 41982bca1ede50049f2f8c7109dd18edeefde6d0 /libraries/pack200/src/unpack200.cpp | |
parent | 47e37635f50c09b4f9a9ee7699e3120bab3e4088 (diff) | |
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NOISSUE reorganize and document libraries
Diffstat (limited to 'libraries/pack200/src/unpack200.cpp')
-rw-r--r-- | libraries/pack200/src/unpack200.cpp | 162 |
1 files changed, 162 insertions, 0 deletions
diff --git a/libraries/pack200/src/unpack200.cpp b/libraries/pack200/src/unpack200.cpp new file mode 100644 index 00000000..22b7f3b0 --- /dev/null +++ b/libraries/pack200/src/unpack200.cpp @@ -0,0 +1,162 @@ +/* + * Copyright (c) 2003, 2008, Oracle and/or its affiliates. All rights reserved. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. + * + * This code is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 only, as + * published by the Free Software Foundation. Oracle designates this + * particular file as subject to the "Classpath" exception as provided + * by Oracle in the LICENSE file that accompanied this code. + * + * This code 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 + * version 2 for more details (a copy is included in the LICENSE file that + * accompanied this code). + * + * You should have received a copy of the GNU General Public License version + * 2 along with this work; if not, write to the Free Software Foundation, + * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. + * + * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA + * or visit www.oracle.com if you need additional information or have any + * questions. + */ +#include <sys/types.h> +#include <stdio.h> +#include <string.h> +#include <stdlib.h> +#include <stdarg.h> +#include <errno.h> +#include <assert.h> +#include <limits.h> +#include <time.h> +#include <stdint.h> + +#include "constants.h" +#include "utils.h" +#include "defines.h" +#include "bytes.h" +#include "coding.h" +#include "unpack200.h" +#include "unpack.h" +#include "zip.h" + +// Callback for fetching data, Unix style. +static int64_t read_input_via_stdio(unpacker *u, void *buf, int64_t minlen, int64_t maxlen) +{ + assert(u->infileptr != nullptr); + assert(minlen <= maxlen); // don't talk nonsense + int64_t numread = 0; + char *bufptr = (char *)buf; + while (numread < minlen) + { + // read available input, up to buf.length or maxlen + int readlen = (1 << 16); + if (readlen > (maxlen - numread)) + readlen = (int)(maxlen - numread); + int nr = 0; + + nr = (int)fread(bufptr, 1, readlen, u->infileptr); + if (nr <= 0) + { + if (errno != EINTR) + break; + nr = 0; + } + numread += nr; + bufptr += nr; + assert(numread <= maxlen); + } + return numread; +} + +enum +{ + EOF_MAGIC = 0, + BAD_MAGIC = -1 +}; + +static int read_magic(unpacker *u, char peek[], int peeklen) +{ + assert(peeklen == 4); // magic numbers are always 4 bytes + int64_t nr = (u->read_input_fn)(u, peek, peeklen, peeklen); + if (nr != peeklen) + { + return (nr == 0) ? EOF_MAGIC : BAD_MAGIC; + } + int magic = 0; + for (int i = 0; i < peeklen; i++) + { + magic <<= 8; + magic += peek[i] & 0xFF; + } + return magic; +} + +void unpack_200(FILE *input, FILE *output) +{ + unpacker u; + u.init(read_input_via_stdio); + + // initialize jar output + // the output takes ownership of the file handle + jar jarout; + jarout.init(&u); + jarout.jarfp = output; + + // the input doesn't + u.infileptr = input; + + // read the magic! + char peek[4]; + int magic; + magic = read_magic(&u, peek, (int)sizeof(peek)); + + // if it is a gzip encoded file, we need an extra gzip input filter + if ((magic & GZIP_MAGIC_MASK) == GZIP_MAGIC) + { + gunzip *gzin = NEW(gunzip, 1); + gzin->init(&u); + // FIXME: why the side effects? WHY? + u.gzin->start(magic); + u.start(); + } + else + { + // otherwise, feed the bytes to the unpacker directly + u.start(peek, sizeof(peek)); + } + + // Note: The checks to u.aborting() are necessary to gracefully + // terminate processing when the first segment throws an error. + for (;;) + { + // Each trip through this loop unpacks one segment + // and then resets the unpacker. + for (unpacker::file *filep; (filep = u.get_next_file()) != nullptr;) + { + u.write_file_to_jar(filep); + } + + // Peek ahead for more data. + magic = read_magic(&u, peek, (int)sizeof(peek)); + if (magic != (int)JAVA_PACKAGE_MAGIC) + { + // we do not feel strongly about this kind of thing... + /* + if (magic != EOF_MAGIC) + unpack_abort("garbage after end of pack archive"); + */ + break; // all done + } + + // Release all storage from parsing the old segment. + u.reset(); + // Restart, beginning with the peek-ahead. + u.start(peek, sizeof(peek)); + } + u.finish(); + u.free(); // tidy up malloc blocks + fclose(input); +} |