NetBSD/gnu/usr.bin/awk/code.c

165 lines
3.5 KiB
C

/********************************************
code.c
copyright 1991, Michael D. Brennan
This is a source file for mawk, an implementation of
the AWK programming language.
Mawk is distributed without warranty under the terms of
the GNU General Public License, version 2, 1991.
********************************************/
/* $Log: code.c,v $
/* Revision 1.2 1993/07/02 23:57:08 jtc
/* Updated to mawk 1.1.4
/*
* Revision 5.1 1991/12/05 07:55:43 brennan
* 1.1 pre-release
*
*/
/* code.c */
#include "mawk.h"
#include "code.h"
#include "init.h"
#include "jmp.h"
#include "field.h"
#define MAIN_CODE_SZ (MAIN_PAGE_SZ*sizeof(INST))
INST *code_ptr ;
INST *main_start , *main_code_ptr ;
#if 0
INST *begin_start , *begin_code_ptr ;
INST *end_start , *end_code_ptr ;
#endif
unsigned main_size /*, begin_size, end_size*/ ;
/* when the code is done executing its freed,
that's why this is global */
struct be_code begin_code , end_code ;
void PROTO(fdump, (void) ) ;
void be_expand( p )
struct be_code *p ;
{ int delta ;
main_code_ptr = code_ptr ;
if ( p->start )
{
delta = p->ptr - p->start ;
p->start = (INST*) zrealloc(p->start, INST_BYTES(p->size),
INST_BYTES(PAGE_SZ)) ;
}
else
{
delta = 0 ;
p->start = (INST*) zmalloc(INST_BYTES(PAGE_SZ)) ;
}
p->size = PAGE_SZ ;
code_ptr = p->start + delta ;
}
void be_shrink(p)
struct be_code *p ;
{
int delta = code_ptr - p->start ;
code_ptr = main_code_ptr ;
if ( delta > p->size )
overflow( p == & begin_code ?
"BEGIN code" : "END code" , p->size) ;
p->start = (INST*) zrealloc(p->start, INST_BYTES(p->size) ,
INST_BYTES(delta+2)) ;
p->ptr = p->start + delta ;
p->size = delta + 2 ;
}
void code_init()
{
code_ptr = main_code_ptr = main_start
= (INST *) zmalloc(MAIN_CODE_SZ) ;
code1(_OMAIN) ;
}
void code_cleanup()
{ int some_code_flag = 0 ; /* might only have functions */
/* set the END code */
if ( end_code.start )
{
end_code.ptr++ -> op = _EXIT0 ;
end_code.ptr++ -> op = _HALT ;
end_code.size = INST_BYTES(end_code.size) ;
}
/* set the main code */
if ( end_code.start || code_ptr - main_start > 1 )
{ int gl_offset = code_ptr - main_start ;
extern INST *next_label ;
extern int NR_flag ;
if ( NR_flag ) code1(OL_GL_NR) ;
else code1(OL_GL) ;
code1(_HALT) ;
main_size = code_ptr - main_start ;
if ( main_size > MAIN_PAGE_SZ )
overflow("MAIN code" , MAIN_PAGE_SZ) ;
main_size *= sizeof(INST) ;
code_ptr = main_start =
(INST*) zrealloc(main_start, MAIN_CODE_SZ, main_size) ;
next_label = main_start+gl_offset ;
some_code_flag = 1 ;
}
else /* only BEGIN */
{
zfree(main_start, MAIN_CODE_SZ) ;
main_start = (INST*) 0 ;
}
/* set the BEGIN code */
if ( begin_code.start )
{
some_code_flag = 1 ;
begin_code.ptr++ -> op = main_start ? _JMAIN : _EXIT0 ;
begin_code.ptr++ -> op = _HALT ;
begin_code.size = INST_BYTES(begin_code.size) ;
/* execution starts at code_ptr */
code_ptr = begin_code.start ;
}
#if ! SM_DOS
if ( dump_code )
{
fdump() ; /* dumps all user functions */
if ( begin_code.start )
{ fprintf(stderr, "BEGIN\n") ; da(begin_code.start, stderr) ; }
if ( end_code.start )
{ fprintf(stderr, "END\n") ; da(end_code.start, stderr) ; }
if ( main_start )
{ fprintf(stderr, "MAIN\n") ; da(main_start, stderr) ; }
}
#endif
if ( some_code_flag == 0 ) mawk_exit(0) ;
}