/*
* CheckHelpBlock - see if a topic is in the 2nd half of a block
*/
static int CheckHelpBlock( HelpFp help_file, char *topic, char *buffer,
long int start )
{
int retn;
char *ftopic;
char *end;
unsigned len;
HelpSeek( help_file, start, HELP_SEEK_SET );
retn = 0;
do {
if( helpGetString( buffer, BUF_LEN, help_file ) == NULL ) {
retn = -1;
break;
}
} while( memcmp( buffer, "::::", 4 ) != 0 );
if( retn == 0 ) {
ftopic = scanTopic( buffer, &end );
len = end - ftopic;
retn = strnicmp( topic, ftopic, len );
if( !retn && topic[len] != '\0' ) {
retn = 1;
}
}
return( retn );
}
static void seek_line( int line )
{
int i;
if( line > lastHelpLine ) {
HelpSeek( helpFileHdl, topPos + helpPos[lastHelpLine], HELP_SEEK_SET );
for( i = lastHelpLine; ; ++i ) {
save_line( i, HelpTell( helpFileHdl ) );
if( i == line )
break;
if( !mygetline() || strnicmp( helpInBuf, "::::", 4 ) == 0 ) {
maxLine = i;
break;
}
}
} else if( line >= 0 ) {
HelpSeek( helpFileHdl, topPos + helpPos[line], HELP_SEEK_SET );
}
}
/*
* OpenTopicInFile - open a help file and look for a topic
*/
static int OpenTopicInFile( help_file *fileinfo, char *topic, char *buffer )
{
long int start_offset; /* - starting offset in HELP file */
long int size_left; /* - size left to search */
int next_posn; /* - contains indicator for next pos'n */
unsigned long topic_pos;
if( fileinfo->f == -1 )
return( 0 );
if( fileinfo->searchhdl != NULL ) {
/* search by new method */
topic_pos = HelpFindTopicOffset( fileinfo->searchhdl, topic );
if( topic_pos == (unsigned long)-1 ) {
return( 0 );
} else {
HelpSeek( fileinfo->f, topic_pos, HELP_SEEK_SET );
if( helpGetString( buffer, BUF_LEN, fileinfo->f ) == NULL ) {
return( 0 );
} else {
return( 1 );
}
}
} else {
start_offset = 0L;
}
size_left = HelpFileLen( fileinfo->f );
do {
size_left = size_left / 2;
if( size_left <= 8 ) {
if( CheckHelpBlock( fileinfo->f, topic, buffer, start_offset ) != 0 ) {
return( 0 );
} else {
return( 1 );
}
}
next_posn = CheckHelpBlock( fileinfo->f, topic, buffer, start_offset + size_left );
if( next_posn > 0 ) {
start_offset += size_left;
}
} while( next_posn != 0 );
return( 1 );
}
/*
* helpGetString
*/
static char *helpGetString( char *buf, size_t size, HelpFp fp )
{
long int pos;
int bytesread;
int cnt;
pos = HelpTell( fp );
bytesread = HelpRead( fp, buf, size - 1 );
if( bytesread == 0 || bytesread == -1 )
return( NULL );
for( cnt = 0; cnt < bytesread; ++cnt ) {
if( buf[cnt] == '\n' ) {
cnt++;
break;
}
}
HelpSeek( fp, pos + cnt, HELP_SEEK_SET );
buf[cnt] = '\0';
return( buf );
}
static void loadPage( HelpHdl hdl, unsigned long pagenum )
{
unsigned long offset;
unsigned tmp;
if( curFile == hdl->fp && pageHeader->page_num == pagenum ) return;
if( hdl->header.ver_maj == 1 ) {
tmp = sizeof( HelpHeader ) - sizeof( uint_16 ); // no str_size
} else {
tmp = sizeof( HelpHeader );
}
offset = tmp + hdl->header.str_size + pagenum * PAGE_SIZE
+ hdl->header.datapagecnt * sizeof( uint_16 );
HelpSeek( hdl->fp, offset, HELP_SEEK_SET );
HelpRead( hdl->fp, curPage, PAGE_SIZE );
curFile = hdl->fp;
pageHeader = (HelpPageHeader *)curPage;
pageIndex = curPage + sizeof( HelpPageHeader );
if( pageHeader->type == PAGE_DATA ) {
stringBlock = curPage + sizeof( HelpPageHeader )
+ pageHeader->num_entries * sizeof( PageIndexEntry );
}
}
HelpHdl InitHelpSearch( HelpFp fp )
{
HelpHdl hdl;
unsigned len;
char *topic;
char *description;
uint_16 str_cnt;
uint_16 *str_len;
char *ptr;
char *buffer;
HelpSeek( fp, 0, HELP_SEEK_SET );
hdl = HelpMemAlloc( sizeof( struct HelpHdl ) );
hdl->fp = fp;
HelpRead( fp, &( hdl->header ), sizeof( HelpHeader ) );
if( hdl->header.sig[0] != HELP_SIG_1
|| hdl->header.sig[1] != HELP_SIG_2
|| hdl->header.ver_min != HELP_MIN_VER ) {
HelpMemFree( hdl );
hdl = NULL;
} else if( hdl->header.ver_maj != HELP_MAJ_VER ) {
if( hdl->header.ver_maj != 1 ) {
HelpMemFree( hdl );
hdl = NULL;
} else {
HelpSeek( fp, -sizeof( uint_16 ), SEEK_CUR ); // no str_size in header
topic = HelpMemAlloc( strlen( DEFAULTTOPIC ) + 1 );
strcpy( topic, DEFAULTTOPIC );
hdl->def_topic = topic;
hdl->desc_str = NULL;
hdl->header.str_size = 0; // no str_size in old header format
len = hdl->header.datapagecnt * sizeof( uint_16 );
hdl->itemindex = HelpMemAlloc( len );
HelpRead( fp, hdl->itemindex, len );
}
} else {
buffer = HelpMemAlloc( hdl->header.str_size );
HelpRead( fp, buffer, hdl->header.str_size );
ptr = buffer;
str_len = (uint_16 *)ptr;
str_cnt = *str_len;
str_len++;
if( *str_len != 0 ) {
topic = HelpMemAlloc( *str_len );
ptr += (str_cnt + 1) * sizeof( uint_16 );
strcpy( topic, ptr); // assume topic is first string
} else {
topic = HelpMemAlloc( strlen( DEFAULTTOPIC ) + 1 );
strcpy( topic, DEFAULTTOPIC );
}
ptr = buffer;
ptr += ( str_cnt + 1 ) * ( sizeof( uint_16 ) );
ptr += ( *str_len ) * ( sizeof( char ) );
str_len++;
if( *str_len != 0 ) {
description = HelpMemAlloc( *str_len );
strcpy( description, ptr );
} else {
description = NULL;
}
HelpMemFree( buffer );
hdl->def_topic = topic;
hdl->desc_str = description;
len = ( hdl->header.datapagecnt ) * ( sizeof( uint_16 ) );
hdl->itemindex = HelpMemAlloc( len );
HelpRead( fp, hdl->itemindex, len );
}
return( hdl );
}
