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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 12:57:57 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 12:57:57 +0000
commit781212c1c1b037543d0c2b689ffde42eb1ac33fc (patch)
tree3412fa60ddeb5bba10e2b6486076a99da9bc8f8e /in_place.c
parentInitial commit. (diff)
downloadxlunzip-781212c1c1b037543d0c2b689ffde42eb1ac33fc.tar.xz
xlunzip-781212c1c1b037543d0c2b689ffde42eb1ac33fc.zip
Adding upstream version 0.8.upstream/0.8upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'in_place.c')
-rw-r--r--in_place.c212
1 files changed, 212 insertions, 0 deletions
diff --git a/in_place.c b/in_place.c
new file mode 100644
index 0000000..11b9cbc
--- /dev/null
+++ b/in_place.c
@@ -0,0 +1,212 @@
+/* Xlunzip - Test tool for the lzip_decompress linux module
+ Copyright (C) 2016-2024 Antonio Diaz Diaz.
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 2 of the License, or
+ (at your option) any later version.
+
+ This program 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 for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define _FILE_OFFSET_BITS 64
+
+#include <errno.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdint.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "linux_lunzip.h"
+#include "lzip.h"
+
+
+/* Return the number of bytes really read.
+ If (value returned < size) and (errno == 0), means EOF was reached.
+*/
+static long readblock( const int fd, uint8_t * const buf, const long size )
+ {
+ long sz = 0;
+ errno = 0;
+ while( sz < size )
+ {
+ const int n = read( fd, buf + sz, min( 1L << 20, size - sz ) );
+ if( n > 0 ) sz += n;
+ else if( n == 0 ) break; /* EOF */
+ else if( errno != EINTR ) break;
+ errno = 0;
+ }
+ return sz;
+ }
+
+
+/* Return the address of a malloc'd buffer containing the file data and
+ the buffer and file sizes in '*buffer_sizep' and '*file_sizep'.
+ In case of error, return 0 and do not modify '*sizep'.
+*/
+static uint8_t * read_file( const int infd, long * const buffer_sizep,
+ long * const file_sizep, const char * const filename )
+ {
+ long buffer_size = 1 << 20;
+ uint8_t * buffer = (uint8_t *)malloc( buffer_size );
+ if( !buffer ) { show_file_error( filename, mem_msg, 0 ); return 0; }
+
+ long file_size = readblock( infd, buffer, buffer_size );
+ while( file_size >= buffer_size && !errno )
+ {
+ if( buffer_size >= LONG_MAX )
+ { show_file_error( filename, "Input file is too large.", 0 );
+ free( buffer ); return 0; }
+ buffer_size = ( buffer_size <= LONG_MAX / 2 ) ? 2 * buffer_size : LONG_MAX;
+ uint8_t * const tmp = (uint8_t *)realloc( buffer, buffer_size );
+ if( !tmp )
+ { show_file_error( filename, mem_msg, 0 ); free( buffer ); return 0; }
+ buffer = tmp;
+ file_size += readblock( infd, buffer + file_size, buffer_size - file_size );
+ }
+ if( errno )
+ { show_file_error( filename, "Error reading file", errno ); free( buffer );
+ return 0; }
+ *buffer_sizep = buffer_size;
+ *file_sizep = file_size;
+ return buffer;
+ }
+
+
+struct File_sizes
+ {
+ unsigned long long csize; /* compressed size */
+ unsigned long long dsize; /* decompressed size */
+ unsigned long tsize; /* trailing data size */
+ long members;
+ };
+
+static const char * set_file_sizes( struct File_sizes * const file_sizes,
+ const uint8_t * const buffer,
+ const unsigned long file_size )
+ {
+ if( file_size <= Lh_size ) return "File ends unexpectedly at member header.";
+ if( file_size < min_member_size ) return "Input file is too short.";
+ const Lzip_header * header = (const Lzip_header *)buffer;
+ if( !Lh_check_magic( *header ) )
+ return "Bad magic number (file not in lzip format).";
+ if( !Lh_check_version( *header ) )
+ return "Version of lzip member format not supported.";
+
+ file_sizes->csize = file_sizes->dsize = file_sizes->tsize = 0;
+ file_sizes->members = 0;
+ unsigned long pos = file_size; /* always points to a header or to EOF */
+ while( pos >= min_member_size )
+ {
+ const Lzip_trailer * const trailer =
+ (const Lzip_trailer *)( buffer + pos - Lt_size );
+ const unsigned long long member_size = Lt_get_member_size( *trailer );
+ if( member_size < min_member_size || member_size > pos )
+ {
+ if( file_sizes->csize == 0 ) /* maybe trailing data */
+ {
+ if( member_size == 0 ) /* skip trailing zeros */
+ while( pos > Lt_size && buffer[pos-8] == 0 ) --pos;
+ else --pos;
+ continue;
+ }
+ return "Member size in trailer is corrupt.";
+ }
+ header = (const Lzip_header *)( buffer + pos - member_size );
+ if( !Lh_check_magic( *header ) || !Lh_check_version( *header ) )
+ {
+ if( file_sizes->csize == 0 ) { --pos; continue; } /* maybe trailing data */
+ return "Bad member header inside file.";
+ }
+ if( file_sizes->csize == 0 && file_size - pos > 0 )
+ {
+ file_sizes->tsize = file_size - pos;
+ header = (const Lzip_header *)( buffer + pos );
+ if( file_size - pos > Lh_size &&
+ Lh_check_magic( *header ) && Lh_check_version( *header ) )
+ return "Last member in input file is truncated or corrupt.";
+ }
+ pos -= member_size;
+ file_sizes->csize += member_size;
+ file_sizes->dsize += Lt_get_data_size( *trailer );
+ ++file_sizes->members;
+ }
+ if( pos != 0 || file_sizes->csize == 0 ) return "Can't get file sizes.";
+ if( file_sizes->csize + file_sizes->tsize != file_size )
+ return "Error getting file sizes.";
+ if( file_sizes->csize > LONG_MAX ) return "File is larger than LONG_MAX.";
+ if( file_sizes->dsize > LONG_MAX ) return "Data is larger than LONG_MAX.";
+ return 0;
+ }
+
+
+static const char * global_name; /* copy of filename for 'error' */
+static void error(char *x) { show_file_error( global_name, x, 0 ); }
+
+
+/*
+ * Load the compressed file at the end of the buffer used to hold the
+ * decompressed data. Check that the in-place decompression does not
+ * overwrite the compressed data. The buffer must be large enough to contain
+ * after the decompressed data extra space for a marker, a trailer, the
+ * maximum possible data expansion, and (if multimember) N-1 empty members.
+ *
+ * |------ compressed data ------|
+ * V V
+ * |----------------|-------------------|---------|
+ * ^ ^ extra
+ * |-------- decompressed data ---------|
+ */
+
+int decompress_in_place( const int infd, struct Pretty_print * const pp,
+ const bool testing )
+ {
+ long buffer_size = 0, file_size = 0;
+ uint8_t * buffer = read_file( infd, &buffer_size, &file_size, pp->name );
+ if( !buffer ) return 1;
+ struct File_sizes file_sizes;
+ const char * emsg = set_file_sizes( &file_sizes, buffer, file_size );
+ if( emsg ) { show_file_error( pp->name, emsg, 0 ); return 2; }
+
+ const long csize = file_sizes.csize;
+ const long dsize = file_sizes.dsize;
+/* const long extra_bytes = ( dsize >> 8 ) + 65536; wrong linux formula */
+ const long extra_bytes = ( csize >> 6 ) + file_sizes.members * min_member_size;
+ const long long target_buffer_size = max( dsize, csize ) + extra_bytes;
+ if( target_buffer_size > LONG_MAX )
+ { show_file_error( pp->name, "Buffer is larger than LONG_MAX.", 0 );
+ return 1; }
+ if( buffer_size < target_buffer_size ) /* avoid realloc if big enough */
+ {
+ buffer = (uint8_t *)realloc( buffer, target_buffer_size );
+ if( !buffer ) { show_file_error( pp->name, mem_msg, 0 ); return 1; }
+ }
+ buffer_size = target_buffer_size;
+ const long cbegin = buffer_size - csize; /* overwrite trailing data */
+ if( cbegin > 0 ) memmove( buffer + cbegin, buffer, csize );
+
+ long in_pos, out_pos;
+ int retval;
+ global_name = pp->name;
+ retval = convert_retval( __lunzip( buffer + cbegin, csize, 0, 0, buffer,
+ buffer_size, &in_pos, &out_pos, error ) );
+ if( retval == 0 && !testing )
+ {
+ const long len = flush( buffer, out_pos );
+ if( len < out_pos )
+ { show_file_error( pp->name, "Write error", errno ); return 1; }
+ }
+ free( buffer );
+ if( retval ) return retval;
+ show_results( pp, in_pos, out_pos, testing );
+ return 0;
+ }