/*************************************************************************** unzip.c Functions to manipulate data within ZIP files. **************************************************************************** Copyright Aaron Giles All rights reserved. Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met: * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. * 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. * Neither the name 'MAME' nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. THIS SOFTWARE IS PROVIDED BY AARON GILES ''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 AARON GILES 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 "osdcore.h" #include "unzip.h" #include #include #include /*************************************************************************** CONSTANTS ***************************************************************************/ /* number of open files to cache */ #define ZIP_CACHE_SIZE 8 /* offsets in end of central directory structure */ #define ZIPESIG 0x00 #define ZIPEDSK 0x04 #define ZIPECEN 0x06 #define ZIPENUM 0x08 #define ZIPECENN 0x0a #define ZIPECSZ 0x0c #define ZIPEOFST 0x10 #define ZIPECOML 0x14 #define ZIPECOM 0x16 /* offsets in central directory entry structure */ #define ZIPCENSIG 0x00 #define ZIPCVER 0x04 #define ZIPCOS 0x05 #define ZIPCVXT 0x06 #define ZIPCEXOS 0x07 #define ZIPCFLG 0x08 #define ZIPCMTHD 0x0a #define ZIPCTIM 0x0c #define ZIPCDAT 0x0e #define ZIPCCRC 0x10 #define ZIPCSIZ 0x14 #define ZIPCUNC 0x18 #define ZIPCFNL 0x1c #define ZIPCXTL 0x1e #define ZIPCCML 0x20 #define ZIPDSK 0x22 #define ZIPINT 0x24 #define ZIPEXT 0x26 #define ZIPOFST 0x2a #define ZIPCFN 0x2e /* offsets in local file header structure */ #define ZIPLOCSIG 0x00 #define ZIPVER 0x04 #define ZIPGENFLG 0x06 #define ZIPMTHD 0x08 #define ZIPTIME 0x0a #define ZIPDATE 0x0c #define ZIPCRC 0x0e #define ZIPSIZE 0x12 #define ZIPUNCMP 0x16 #define ZIPFNLN 0x1a #define ZIPXTRALN 0x1c #define ZIPNAME 0x1e /*************************************************************************** INLINE FUNCTIONS ***************************************************************************/ INLINE UINT16 read_word(UINT8 *buf) { return (buf[1] << 8) | buf[0]; } INLINE UINT32 read_dword(UINT8 *buf) { return (buf[3] << 24) | (buf[2] << 16) | (buf[1] << 8) | buf[0]; } /*************************************************************************** GLOBAL VARIABLES ***************************************************************************/ static zip_file *zip_cache[ZIP_CACHE_SIZE]; /*************************************************************************** FUNCTION PROTOTYPES ***************************************************************************/ /* cache management */ static void free_zip_file(zip_file *zip); /* ZIP file parsing */ static zip_error read_ecd(zip_file *zip); static zip_error get_compressed_data_offset(zip_file *zip, UINT64 *offset); /* decompression interfaces */ static zip_error decompress_data_type_0(zip_file *zip, UINT64 offset, void *buffer, UINT32 length); static zip_error decompress_data_type_8(zip_file *zip, UINT64 offset, void *buffer, UINT32 length); /*************************************************************************** ZIP FILE ACCESS ***************************************************************************/ /*------------------------------------------------- zip_file_open - opens a ZIP file for reading -------------------------------------------------*/ zip_error zip_file_open(const char *filename, zip_file **zip) { zip_error ziperr = ZIPERR_NONE; file_error filerr; UINT32 read_length; zip_file *newzip; char *string; int cachenum; /* ensure we start with a NULL result */ *zip = NULL; /* see if we are in the cache, and reopen if so */ for (cachenum = 0; cachenum < ARRAY_LENGTH(zip_cache); cachenum++) { zip_file *cached = zip_cache[cachenum]; /* if we have a valid entry and it matches our filename, use it and remove from the cache */ if (cached != NULL && cached->filename != NULL && strcmp(filename, cached->filename) == 0) { *zip = cached; zip_cache[cachenum] = NULL; return ZIPERR_NONE; } } /* allocate memory for the zip_file structure */ newzip = (zip_file *)malloc(sizeof(*newzip)); if (newzip == NULL) return ZIPERR_OUT_OF_MEMORY; memset(newzip, 0, sizeof(*newzip)); /* open the file */ filerr = osd_open(filename, OPEN_FLAG_READ, &newzip->file, &newzip->length); if (filerr != FILERR_NONE) { ziperr = ZIPERR_FILE_ERROR; goto error; } /* read ecd data */ ziperr = read_ecd(newzip); if (ziperr != ZIPERR_NONE) goto error; /* verify that we can work with this zipfile (no disk spanning allowed) */ if (newzip->ecd.disk_number != newzip->ecd.cd_start_disk_number || newzip->ecd.cd_disk_entries != newzip->ecd.cd_total_entries) { ziperr = ZIPERR_UNSUPPORTED; goto error; } /* allocate memory for the central directory */ newzip->cd = (UINT8 *)malloc(newzip->ecd.cd_size + 1); if (newzip->cd == NULL) { ziperr = ZIPERR_OUT_OF_MEMORY; goto error; } /* read the central directory */ filerr = osd_read(newzip->file, newzip->cd, newzip->ecd.cd_start_disk_offset, newzip->ecd.cd_size, &read_length); if (filerr != FILERR_NONE || read_length != newzip->ecd.cd_size) { ziperr = (filerr == FILERR_NONE) ? ZIPERR_FILE_TRUNCATED : ZIPERR_FILE_ERROR; goto error; } /* make a copy of the filename for caching purposes */ string = (char *)malloc(strlen(filename) + 1); if (string == NULL) { ziperr = ZIPERR_OUT_OF_MEMORY; goto error; } strcpy(string, filename); newzip->filename = string; *zip = newzip; return ZIPERR_NONE; error: free_zip_file(newzip); return ziperr; } /*------------------------------------------------- zip_file_close - close a ZIP file and add it to the cache -------------------------------------------------*/ void zip_file_close(zip_file *zip) { int cachenum; /* close the open files */ if (zip->file != NULL) osd_close(zip->file); zip->file = NULL; /* find the first NULL entry in the cache */ for (cachenum = 0; cachenum < ARRAY_LENGTH(zip_cache); cachenum++) if (zip_cache[cachenum] == NULL) break; /* if no room left in the cache, free the bottommost entry */ if (cachenum == ARRAY_LENGTH(zip_cache)) free_zip_file(zip_cache[--cachenum]); /* move everyone else down and place us at the top */ if (cachenum != 0) memmove(&zip_cache[1], &zip_cache[0], cachenum * sizeof(zip_cache[0])); zip_cache[0] = zip; } /*------------------------------------------------- zip_file_cache_clear - clear the ZIP file cache and free all memory -------------------------------------------------*/ void zip_file_cache_clear(void) { int cachenum; /* clear call cache entries */ for (cachenum = 0; cachenum < ARRAY_LENGTH(zip_cache); cachenum++) if (zip_cache[cachenum] != NULL) { free_zip_file(zip_cache[cachenum]); zip_cache[cachenum] = NULL; } } /*************************************************************************** CONTAINED FILE ACCESS ***************************************************************************/ /*------------------------------------------------- zip_file_first_entry - return the first entry in the ZIP -------------------------------------------------*/ const zip_file_header *zip_file_first_file(zip_file *zip) { /* reset the position and go from there */ zip->cd_pos = 0; return zip_file_next_file(zip); } /*------------------------------------------------- zip_file_next_entry - return the next entry in the ZIP -------------------------------------------------*/ const zip_file_header *zip_file_next_file(zip_file *zip) { /* fix up any modified data */ if (zip->header.raw != NULL) { zip->header.raw[ZIPCFN + zip->header.filename_length] = zip->header.saved; zip->header.raw = NULL; } /* if we're at or past the end, we're done */ if (zip->cd_pos >= zip->ecd.cd_size) return NULL; /* extract file header info */ zip->header.raw = zip->cd + zip->cd_pos; zip->header.rawlength = ZIPCFN; zip->header.signature = read_dword(zip->header.raw + ZIPCENSIG); zip->header.version_created = read_word (zip->header.raw + ZIPCVER); zip->header.version_needed = read_word (zip->header.raw + ZIPCVXT); zip->header.bit_flag = read_word (zip->header.raw + ZIPCFLG); zip->header.compression = read_word (zip->header.raw + ZIPCMTHD); zip->header.file_time = read_word (zip->header.raw + ZIPCTIM); zip->header.file_date = read_word (zip->header.raw + ZIPCDAT); zip->header.crc = read_dword(zip->header.raw + ZIPCCRC); zip->header.compressed_length = read_dword(zip->header.raw + ZIPCSIZ); zip->header.uncompressed_length = read_dword(zip->header.raw + ZIPCUNC); zip->header.filename_length = read_word (zip->header.raw + ZIPCFNL); zip->header.extra_field_length = read_word (zip->header.raw + ZIPCXTL); zip->header.file_comment_length = read_word (zip->header.raw + ZIPCCML); zip->header.start_disk_number = read_word (zip->header.raw + ZIPDSK); zip->header.internal_attributes = read_word (zip->header.raw + ZIPINT); zip->header.external_attributes = read_dword(zip->header.raw + ZIPEXT); zip->header.local_header_offset = read_dword(zip->header.raw + ZIPOFST); zip->header.filename = (char *)zip->header.raw + ZIPCFN; /* make sure we have enough data */ zip->header.rawlength += zip->header.filename_length; zip->header.rawlength += zip->header.extra_field_length; zip->header.rawlength += zip->header.file_comment_length; if (zip->cd_pos + zip->header.rawlength > zip->ecd.cd_size) return NULL; /* NULL terminate the filename */ zip->header.saved = zip->header.raw[ZIPCFN + zip->header.filename_length]; zip->header.raw[ZIPCFN + zip->header.filename_length] = 0; /* advance the position */ zip->cd_pos += zip->header.rawlength; return &zip->header; } /*------------------------------------------------- zip_file_decompress - decompress a file from a ZIP into the target buffer -------------------------------------------------*/ zip_error zip_file_decompress(zip_file *zip, void *buffer, UINT32 length) { zip_error ziperr; UINT64 offset; /* if we don't have enough buffer, error */ if (length < zip->header.uncompressed_length) return ZIPERR_BUFFER_TOO_SMALL; /* make sure the info in the header aligns with what we know */ if (zip->header.start_disk_number != zip->ecd.disk_number) return ZIPERR_UNSUPPORTED; /* get the compressed data offset */ ziperr = get_compressed_data_offset(zip, &offset); if (ziperr != ZIPERR_NONE) return ziperr; /* handle compression types */ switch (zip->header.compression) { case 0: ziperr = decompress_data_type_0(zip, offset, buffer, length); break; case 8: ziperr = decompress_data_type_8(zip, offset, buffer, length); break; default: ziperr = ZIPERR_UNSUPPORTED; break; } return ziperr; } /*************************************************************************** CACHE MANAGEMENT ***************************************************************************/ /*------------------------------------------------- free_zip_file - free all the data for a zip_file -------------------------------------------------*/ static void free_zip_file(zip_file *zip) { if (zip != NULL) { if (zip->file != NULL) osd_close(zip->file); if (zip->filename != NULL) free((void *)zip->filename); if (zip->ecd.raw != NULL) free(zip->ecd.raw); if (zip->cd != NULL) free(zip->cd); free(zip); } } /*************************************************************************** ZIP FILE PARSING ***************************************************************************/ /*------------------------------------------------- read_ecd - read the ECD data -------------------------------------------------*/ static zip_error read_ecd(zip_file *zip) { UINT32 buflen = 1024; UINT8 *buffer; /* we may need multiple tries */ while (buflen < 65536) { file_error error; UINT32 read_length; INT32 offset; /* max out the buffer length at the size of the file */ if (buflen > zip->length) buflen = zip->length; /* allocate buffer */ buffer = (UINT8 *)malloc(buflen + 1); if (buffer == NULL) return ZIPERR_OUT_OF_MEMORY; /* read in one buffers' worth of data */ error = osd_read(zip->file, buffer, zip->length - buflen, buflen, &read_length); if (error != FILERR_NONE || read_length != buflen) { free(buffer); return ZIPERR_FILE_ERROR; } /* find the ECD signature */ for (offset = buflen - 22; offset >= 0; offset--) if (buffer[offset + 0] == 'P' && buffer[offset + 1] == 'K' && buffer[offset + 2] == 0x05 && buffer[offset + 3] == 0x06) break; /* if we found it, fill out the data */ if (offset >= 0) { /* reuse the buffer as our ECD buffer */ zip->ecd.raw = buffer; zip->ecd.rawlength = buflen - offset; /* append a NULL terminator to the comment */ memmove(&buffer[0], &buffer[offset], zip->ecd.rawlength); zip->ecd.raw[zip->ecd.rawlength] = 0; /* extract ecd info */ zip->ecd.signature = read_dword(zip->ecd.raw + ZIPESIG); zip->ecd.disk_number = read_word (zip->ecd.raw + ZIPEDSK); zip->ecd.cd_start_disk_number = read_word (zip->ecd.raw + ZIPECEN); zip->ecd.cd_disk_entries = read_word (zip->ecd.raw + ZIPENUM); zip->ecd.cd_total_entries = read_word (zip->ecd.raw + ZIPECENN); zip->ecd.cd_size = read_dword(zip->ecd.raw + ZIPECSZ); zip->ecd.cd_start_disk_offset = read_dword(zip->ecd.raw + ZIPEOFST); zip->ecd.comment_length = read_word (zip->ecd.raw + ZIPECOML); zip->ecd.comment = (const char *)(zip->ecd.raw + ZIPECOM); return ZIPERR_NONE; } /* didn't find it; free this buffer and expand our search */ free(buffer); if (buflen < zip->length) buflen *= 2; else return ZIPERR_BAD_SIGNATURE; } return ZIPERR_OUT_OF_MEMORY; } /*------------------------------------------------- get_compressed_data_offset - return the offset of the compressed data -------------------------------------------------*/ static zip_error get_compressed_data_offset(zip_file *zip, UINT64 *offset) { file_error error; UINT32 read_length; /* make sure the file handle is open */ if (zip->file == NULL) { int filerr = osd_open(zip->filename, OPEN_FLAG_READ, &zip->file, &zip->length); if (filerr != FILERR_NONE) return ZIPERR_FILE_ERROR; } /* now go read the fixed-sized part of the local file header */ error = osd_read(zip->file, zip->buffer, zip->header.local_header_offset, ZIPNAME, &read_length); if (error != FILERR_NONE || read_length != ZIPNAME) return (error == FILERR_NONE) ? ZIPERR_FILE_TRUNCATED : ZIPERR_FILE_ERROR; /* compute the final offset */ *offset = zip->header.local_header_offset + ZIPNAME; *offset += read_word(zip->buffer + ZIPFNLN); *offset += read_word(zip->buffer + ZIPXTRALN); return ZIPERR_NONE; } /*************************************************************************** DECOMPRESSION INTERFACES ***************************************************************************/ /*------------------------------------------------- decompress_data_type_0 - "decompress" type 0 data (which is uncompressed) -------------------------------------------------*/ static zip_error decompress_data_type_0(zip_file *zip, UINT64 offset, void *buffer, UINT32 length) { file_error filerr; UINT32 read_length; /* the data is uncompressed; just read it */ filerr = osd_read(zip->file, buffer, offset, zip->header.compressed_length, &read_length); if (filerr != FILERR_NONE) return ZIPERR_FILE_ERROR; else if (read_length != zip->header.compressed_length) return ZIPERR_FILE_TRUNCATED; else return ZIPERR_NONE; } /*------------------------------------------------- decompress_data_type_8 - decompress type 8 data (which is deflated) -------------------------------------------------*/ static zip_error decompress_data_type_8(zip_file *zip, UINT64 offset, void *buffer, UINT32 length) { UINT32 input_remaining = zip->header.compressed_length; UINT32 read_length; z_stream stream; int filerr; int zerr; /* make sure we don't need a newer mechanism */ if (zip->header.version_needed > 0x14) return ZIPERR_UNSUPPORTED; /* reset the stream */ memset(&stream, 0, sizeof(stream)); stream.next_out = (Bytef *)buffer; stream.avail_out = length; /* initialize the decompressor */ zerr = inflateInit2(&stream, -MAX_WBITS); if (zerr != Z_OK) return ZIPERR_DECOMPRESS_ERROR; /* loop until we're done */ while (1) { /* read in the next chunk of data */ filerr = osd_read(zip->file, zip->buffer, offset, MIN(input_remaining, sizeof(zip->buffer)), &read_length); if (filerr != FILERR_NONE) { inflateEnd(&stream); return ZIPERR_FILE_ERROR; } offset += read_length; /* if we read nothing, but still have data left, the file is truncated */ if (read_length == 0 && input_remaining > 0) { inflateEnd(&stream); return ZIPERR_FILE_TRUNCATED; } /* fill out the input data */ stream.next_in = zip->buffer; stream.avail_in = read_length; input_remaining -= read_length; /* add a dummy byte at end of compressed data */ if (input_remaining == 0) stream.avail_in++; /* now inflate */ zerr = inflate(&stream, Z_NO_FLUSH); if (zerr == Z_STREAM_END) break; if (zerr != Z_OK) { inflateEnd(&stream); return ZIPERR_DECOMPRESS_ERROR; } } /* finish decompression */ zerr = inflateEnd(&stream); if (zerr != Z_OK) return ZIPERR_DECOMPRESS_ERROR; /* if anything looks funny, report an error */ if (stream.avail_out > 0 || input_remaining > 0) return ZIPERR_DECOMPRESS_ERROR; return ZIPERR_NONE; }