audk/EdkCompatibilityPkg/Other/Maintained/Tools/Pccts/h/ATokenBuffer.cpp

346 lines
10 KiB
C++

/* ANTLRTokenBuffer.C
*
* SOFTWARE RIGHTS
*
* We reserve no LEGAL rights to the Purdue Compiler Construction Tool
* Set (PCCTS) -- PCCTS is in the public domain. An individual or
* company may do whatever they wish with source code distributed with
* PCCTS or the code generated by PCCTS, including the incorporation of
* PCCTS, or its output, into commerical software.
*
* We encourage users to develop software with PCCTS. However, we do ask
* that credit is given to us for developing PCCTS. By "credit",
* we mean that if you incorporate our source code into one of your
* programs (commercial product, research project, or otherwise) that you
* acknowledge this fact somewhere in the documentation, research report,
* etc... If you like PCCTS and have developed a nice tool with the
* output, please mention that you developed it using PCCTS. In
* addition, we ask that this header remain intact in our source code.
* As long as these guidelines are kept, we expect to continue enhancing
* this system and expect to make other tools available as they are
* completed.
*
* ANTLR 1.33
* Terence Parr
* Parr Research Corporation
* with Purdue University and AHPCRC, University of Minnesota
* 1989-1998
*/
typedef int ANTLRTokenType; // fool AToken.h into compiling
class ANTLRParser; /* MR1 */
#define ANTLR_SUPPORT_CODE
#include "pcctscfg.h"
#include ATOKENBUFFER_H
typedef ANTLRAbstractToken *_ANTLRTokenPtr;
#if defined(DBG_TBUF)||defined(DBG_TBUF_MARK_REW)
static unsigned char test[1000];
#endif
#ifdef DBG_REFCOUNTTOKEN
int ANTLRCommonToken::ctor = 0;
int ANTLRCommonToken::dtor = 0;
#endif
ANTLRTokenBuffer::
ANTLRTokenBuffer(ANTLRTokenStream *_input, int _k, int _chunk_size_formal) /* MR14 */
{
this->input = _input;
this->k = _k;
buffer_size = chunk_size = _chunk_size_formal;
buffer = (_ANTLRTokenPtr *)
calloc(chunk_size+1,sizeof(_ANTLRTokenPtr ));
if ( buffer == NULL ) {
panic("cannot alloc token buffer");
}
buffer++; // leave the first elem empty so tp-1 is valid ptr
tp = &buffer[0];
last = tp-1;
next = &buffer[0];
num_markers = 0;
end_of_buffer = &buffer[buffer_size-1];
// BUGBUG -- threshold = &buffer[(int)(buffer_size*(1.0/2.0))];
threshold = &buffer[(int)(buffer_size / 2)];
_deleteTokens = 1; // assume we delete tokens
parser=NULL; // MR5 - uninitialized reference
}
static void f() {;}
ANTLRTokenBuffer::
~ANTLRTokenBuffer()
{
f();
// Delete all remaining tokens (from 0..last inclusive)
if ( _deleteTokens )
{
_ANTLRTokenPtr *z;
for (z=buffer; z<=last; z++)
{
(*z)->deref();
// z->deref();
#ifdef DBG_REFCOUNTTOKEN
fprintf(stderr, "##########dtor: deleting token '%s' (ref %d)\n",
((ANTLRCommonToken *)*z)->getText(), (*z)->nref());
#endif
if ( (*z)->nref()==0 )
{
delete (*z);
}
}
}
if ( buffer!=NULL ) free((char *)(buffer-1));
}
#if defined(DBG_TBUF)||defined(DBG_TBUF_MARK_REW)
#include "pccts_stdio.h"
PCCTS_NAMESPACE_STD
#endif
_ANTLRTokenPtr ANTLRTokenBuffer::
getToken()
{
if ( tp <= last ) // is there any buffered lookahead still to be read?
{
return *tp++; // read buffered lookahead
}
// out of buffered lookahead, get some more "real"
// input from getANTLRToken()
if ( num_markers==0 )
{
if( next > threshold )
{
#ifdef DBG_TBUF
fprintf(stderr,"getToken: next > threshold (high water is %d)\n", threshold-buffer);
#endif
makeRoom();
}
}
else {
if ( next > end_of_buffer )
{
#ifdef DBG_TBUF
fprintf(stderr,"getToken: next > end_of_buffer (size is %d)\n", buffer_size);
#endif
extendBuffer();
}
}
*next = getANTLRToken();
(*next)->ref(); // say we have a copy of this pointer in buffer
last = next;
next++;
tp = last;
return *tp++;
}
void ANTLRTokenBuffer::
rewind(int pos)
{
#if defined(DBG_TBUF)||defined(DBG_TBUF_MARK_REW)
fprintf(stderr, "rewind(%d)[nm=%d,from=%d,%d.n=%d]\n", pos, num_markers, tp-buffer,pos,test[pos]);
test[pos]--;
#endif
tp = &buffer[pos];
num_markers--;
}
/*
* This function is used to specify that the token pointers read
* by the ANTLRTokenBuffer should be buffered up (to be reused later).
*/
int ANTLRTokenBuffer::
mark()
{
#if defined(DBG_TBUF)||defined(DBG_TBUF_MARK_REW)
test[tp-buffer]++;
fprintf(stderr,"mark(%d)[nm=%d,%d.n=%d]\n",tp-buffer,num_markers+1,tp-buffer,test[tp-buffer]);
#endif
num_markers++;
return tp - buffer;
}
/*
* returns the token pointer n positions ahead.
* This implies that bufferedToken(1) gets the NEXT symbol of lookahead.
* This is used in conjunction with the ANTLRParser lookahead buffer.
*
* No markers are set or anything. A bunch of input is buffered--that's all.
* The tp pointer is left alone as the lookahead has not been advanced
* with getToken(). The next call to getToken() will find a token
* in the buffer and won't have to call getANTLRToken().
*
* If this is called before a consume() is done, how_many_more_i_need is
* set to 'n'.
*/
_ANTLRTokenPtr ANTLRTokenBuffer::
bufferedToken(int n)
{
// int how_many_more_i_need = (last-tp < 0) ? n : n-(last-tp)-1;
int how_many_more_i_need = (tp > last) ? n : n-(last-tp)-1;
// Make sure that at least n tokens are available in the buffer
#ifdef DBG_TBUF
fprintf(stderr, "bufferedToken(%d)\n", n);
#endif
for (int i=1; i<=how_many_more_i_need; i++)
{
if ( next > end_of_buffer ) // buffer overflow?
{
extendBuffer();
}
*next = getANTLRToken();
(*next)->ref(); // say we have a copy of this pointer in buffer
last = next;
next++;
}
return tp[n - 1];
}
/* If no markers are set, the none of the input needs to be saved (except
* for the lookahead Token pointers). We save only k-1 token pointers as
* we are guaranteed to do a getANTLRToken() right after this because otherwise
* we wouldn't have needed to extend the buffer.
*
* If there are markers in the buffer, we need to save things and so
* extendBuffer() is called.
*/
void ANTLRTokenBuffer::
makeRoom()
{
#ifdef DBG_TBUF
fprintf(stderr, "in makeRoom.................\n");
fprintf(stderr, "num_markers==%d\n", num_markers);
#endif
/*
if ( num_markers == 0 )
{
*/
#ifdef DBG_TBUF
fprintf(stderr, "moving lookahead and resetting next\n");
_ANTLRTokenPtr *r;
fprintf(stderr, "tbuf = [");
for (r=buffer; r<=last; r++)
{
if ( *r==NULL ) fprintf(stderr, " xxx");
else fprintf(stderr, " '%s'", ((ANTLRCommonToken *)*r)->getText());
}
fprintf(stderr, " ]\n");
fprintf(stderr,
"before: tp=%d, last=%d, next=%d, threshold=%d\n",tp-buffer,last-buffer,next-buffer,threshold-buffer);
#endif
// Delete all tokens from 0..last-(k-1) inclusive
if ( _deleteTokens )
{
_ANTLRTokenPtr *z;
for (z=buffer; z<=last-(k-1); z++)
{
(*z)->deref();
// z->deref();
#ifdef DBG_REFCOUNTTOKEN
fprintf(stderr, "##########makeRoom: deleting token '%s' (ref %d)\n",
((ANTLRCommonToken *)*z)->getText(), (*z)->nref());
#endif
if ( (*z)->nref()==0 )
{
delete (*z);
}
}
}
// reset the buffer to initial conditions, but move k-1 symbols
// to the beginning of buffer and put new input symbol at k
_ANTLRTokenPtr *p = buffer, *q = last-(k-1)+1;
// ANTLRAbstractToken **p = buffer, **q = end_of_buffer-(k-1)+1;
#ifdef DBG_TBUF
fprintf(stderr, "lookahead buffer = [");
#endif
for (int i=1; i<=(k-1); i++)
{
*p++ = *q++;
#ifdef DBG_TBUF
fprintf(stderr,
" '%s'", ((ANTLRCommonToken *)buffer[i-1])->getText());
#endif
}
#ifdef DBG_TBUF
fprintf(stderr, " ]\n");
#endif
next = &buffer[k-1];
tp = &buffer[k-1]; // tp points to what will be filled in next
last = tp-1;
#ifdef DBG_TBUF
fprintf(stderr,
"after: tp=%d, last=%d, next=%d\n",
tp-buffer, last-buffer, next-buffer);
#endif
/*
}
else {
extendBuffer();
}
*/
}
/* This function extends 'buffer' by chunk_size and returns with all
* pointers at the same relative positions in the buffer (the buffer base
* address could have changed in realloc()) except that 'next' comes
* back set to where the next token should be stored. All other pointers
* are untouched.
*/
void
ANTLRTokenBuffer::
extendBuffer()
{
int save_last = last-buffer, save_tp = tp-buffer, save_next = next-buffer;
#ifdef DBG_TBUF
fprintf(stderr, "extending physical buffer\n");
#endif
buffer_size += chunk_size;
buffer = (_ANTLRTokenPtr *)
realloc((char *)(buffer-1),
(buffer_size+1)*sizeof(_ANTLRTokenPtr ));
if ( buffer == NULL ) {
panic("cannot alloc token buffer");
}
buffer++; // leave the first elem empty so tp-1 is valid ptr
tp = buffer + save_tp; // put the pointers back to same relative position
last = buffer + save_last;
next = buffer + save_next;
end_of_buffer = &buffer[buffer_size-1];
// BUGBUG -- threshold = &buffer[(int)(buffer_size*(1.0/2.0))];
threshold = &buffer[(int)(buffer_size / 2)];
/*
// zero out new token ptrs so we'll know if something to delete in buffer
ANTLRAbstractToken **p = end_of_buffer-chunk_size+1;
for (; p<=end_of_buffer; p++) *p = NULL;
*/
}
ANTLRParser * ANTLRTokenBuffer:: // MR1
setParser(ANTLRParser *p) { // MR1
ANTLRParser *old=parser; // MR1
parser=p; // MR1
input->setParser(p); // MR1
return old; // MR1
} // MR1
// MR1
ANTLRParser * ANTLRTokenBuffer:: // MR1
getParser() { // MR1
return parser; // MR1
} // MR1
/* to avoid having to link in another file just for the smart token ptr
* stuff, we include it here. Ugh.
*/
#include ATOKPTR_C