1 /* 2 * Copyright (C) 2000 Tridia Corporation. All Rights Reserved. 3 * Copyright (C) 1999 AT&T Laboratories Cambridge. All Rights Reserved. 4 * 5 * This is free software; you can redistribute it and/or modify 6 * it under the terms of the GNU General Public License as published by 7 * the Free Software Foundation; either version 2 of the License, or 8 * (at your option) any later version. 9 * 10 * This software is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this software; if not, write to the Free Software 17 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, 18 * USA. 19 */ 20 21 #ifdef LIBVNCSERVER_HAVE_LIBZ 22 23 /* 24 * zlib.c - handle zlib encoding. 25 * 26 * This file shouldn't be compiled directly. It is included multiple times by 27 * rfbproto.c, each time with a different definition of the macro BPP. For 28 * each value of BPP, this file defines a function which handles an zlib 29 * encoded rectangle with BPP bits per pixel. 30 */ 31 32 #define HandleZlibBPP CONCAT2E(HandleZlib,BPP) 33 #define CARDBPP CONCAT3E(uint,BPP,_t) 34 35 static rfbBool 36 HandleZlibBPP (rfbClient* client, int rx, int ry, int rw, int rh) 37 { 38 rfbZlibHeader hdr; 39 int remaining; 40 int inflateResult; 41 int toRead; 42 43 /* First make sure we have a large enough raw buffer to hold the 44 * decompressed data. In practice, with a fixed BPP, fixed frame 45 * buffer size and the first update containing the entire frame 46 * buffer, this buffer allocation should only happen once, on the 47 * first update. 48 */ 49 if ( client->raw_buffer_size < (( rw * rh ) * ( BPP / 8 ))) { 50 51 if ( client->raw_buffer != NULL ) { 52 53 free( client->raw_buffer ); 54 55 } 56 57 client->raw_buffer_size = (( rw * rh ) * ( BPP / 8 )); 58 client->raw_buffer = (char*) malloc( client->raw_buffer_size ); 59 60 } 61 62 if (!ReadFromRFBServer(client, (char *)&hdr, sz_rfbZlibHeader)) 63 return FALSE; 64 65 remaining = rfbClientSwap32IfLE(hdr.nBytes); 66 67 /* Need to initialize the decompressor state. */ 68 client->decompStream.next_in = ( Bytef * )client->buffer; 69 client->decompStream.avail_in = 0; 70 client->decompStream.next_out = ( Bytef * )client->raw_buffer; 71 client->decompStream.avail_out = client->raw_buffer_size; 72 client->decompStream.data_type = Z_BINARY; 73 74 /* Initialize the decompression stream structures on the first invocation. */ 75 if ( client->decompStreamInited == FALSE ) { 76 77 inflateResult = inflateInit( &client->decompStream ); 78 79 if ( inflateResult != Z_OK ) { 80 rfbClientLog( 81 "inflateInit returned error: %d, msg: %s\n", 82 inflateResult, 83 client->decompStream.msg); 84 return FALSE; 85 } 86 87 client->decompStreamInited = TRUE; 88 89 } 90 91 inflateResult = Z_OK; 92 93 /* Process buffer full of data until no more to process, or 94 * some type of inflater error, or Z_STREAM_END. 95 */ 96 while (( remaining > 0 ) && 97 ( inflateResult == Z_OK )) { 98 99 if ( remaining > RFB_BUFFER_SIZE ) { 100 toRead = RFB_BUFFER_SIZE; 101 } 102 else { 103 toRead = remaining; 104 } 105 106 /* Fill the buffer, obtaining data from the server. */ 107 if (!ReadFromRFBServer(client, client->buffer,toRead)) 108 return FALSE; 109 110 client->decompStream.next_in = ( Bytef * )client->buffer; 111 client->decompStream.avail_in = toRead; 112 113 /* Need to uncompress buffer full. */ 114 inflateResult = inflate( &client->decompStream, Z_SYNC_FLUSH ); 115 116 /* We never supply a dictionary for compression. */ 117 if ( inflateResult == Z_NEED_DICT ) { 118 rfbClientLog("zlib inflate needs a dictionary!\n"); 119 return FALSE; 120 } 121 if ( inflateResult < 0 ) { 122 rfbClientLog( 123 "zlib inflate returned error: %d, msg: %s\n", 124 inflateResult, 125 client->decompStream.msg); 126 return FALSE; 127 } 128 129 /* Result buffer allocated to be at least large enough. We should 130 * never run out of space! 131 */ 132 if (( client->decompStream.avail_in > 0 ) && 133 ( client->decompStream.avail_out <= 0 )) { 134 rfbClientLog("zlib inflate ran out of space!\n"); 135 return FALSE; 136 } 137 138 remaining -= toRead; 139 140 } /* while ( remaining > 0 ) */ 141 142 if ( inflateResult == Z_OK ) { 143 144 /* Put the uncompressed contents of the update on the screen. */ 145 CopyRectangle(client, (uint8_t *)client->raw_buffer, rx, ry, rw, rh); 146 } 147 else { 148 149 rfbClientLog( 150 "zlib inflate returned error: %d, msg: %s\n", 151 inflateResult, 152 client->decompStream.msg); 153 return FALSE; 154 155 } 156 157 return TRUE; 158 } 159 160 #undef CARDBPP 161 162 #endif 163
