ack/util/ego/ic/ic_lib.c
1991-03-05 12:16:17 +00:00

300 lines
6.2 KiB
C

/* $Header$ */
/*
* (c) copyright 1987 by the Vrije Universiteit, Amsterdam, The Netherlands.
* See the copyright notice in the ACK home directory, in the file "Copyright".
*/
/* I N T E R M E D I A T E C O D E
*
* I C _ L I B . C
*/
#include <stdio.h>
#include <em_spec.h>
#include <em_pseu.h>
#include <em_mes.h>
#include <arch.h>
#include "../share/types.h"
#include "../share/debug.h"
#include "ic.h"
#include "ic_lookup.h"
#include "ic_io.h"
#include "../share/global.h"
#include "../share/files.h"
#include "ic_lib.h"
STATIC skip_string(n)
offset n;
{
/* Read a string of length n and void it */
while (n--) {
readchar();
}
}
STATIC skip_arguments()
{
/* Skip the arguments of a MES pseudo. The argument
* list is terminated by a sp_cend byte.
*/
for (;;) {
switch(table2()) {
case sp_scon:
get_off(); /* void */
/* fall through !!! */
case sp_icon:
case sp_ucon:
case sp_fcon:
get_int(); /* void */
skip_string(get_off());
break;
case sp_cend:
return;
default:
break;
}
}
}
STATIC bool proc_wanted(name)
char *name;
{
/* See if 'name' is the name of an external procedure
* that has been used before, but for which no body
* has been given so far.
*/
proc_p p;
if (( p = proclookup(name,IMPORTING)) != (proc_p) 0 &&
!(p->p_flags1 & PF_BODYSEEN)) {
return TRUE;
} else {
return FALSE;
}
}
STATIC bool data_wanted(name)
char *name;
{
/* See if 'name' is the name of an externally visible
* data block that has been used before, but for which
* no defining occurrence has been given yet.
*/
dblock_p db;
if ((db = symlookup(name,IMPORTING)) != (dblock_p) 0 &&
db->d_pseudo == DUNKNOWN) {
return TRUE;
} else {
return FALSE;
}
}
STATIC bool wanted_names()
{
/* Read the names of procedures and data labels,
* appearing in a 'MES ms_ext' pseudo. Those are
* the names of entities that are imported by
* a library module.
* If any of them is wanted, return TRUE.
* A name is wanted if it is the name of a procedure
* or data block for which applied occurrences but
* no defining occurrence has been met.
*/
for (;;) {
switch(table2()) {
case DLBX:
if (data_wanted(string)) {
return TRUE;
}
/* A data entity with the name
* string is available.
*/
break;
case sp_pnam:
if (proc_wanted(string)) {
return TRUE;
}
break;
case sp_cend:
return FALSE;
default:
error("wrong argument of MES %d", ms_ext);
}
}
}
STATIC FILE *curfile = NULL;
STATIC bool useful()
{
/* Determine if any entity imported by the current
* compact EM assembly file (which will usually be
* part of an archive file) is useful to us.
* The file must contain (before any other non-MES line)
* a 'MES ms_ext' pseudo that has as arguments the names
* of the entities imported.
*/
for (;;) {
if (table1() != PSEU || tabval != ps_mes) {
error("cannot find MES %d in library file",ms_ext);
}
if (table2() != CSTX1) {
error("message number expected");
}
if (tabval == ms_ext) {
/* This is the one we searched */
return wanted_names();
/* Read the names of the imported entities
* and check if any of them is wanted.
*/
} else {
skip_arguments(); /* skip remainder of this MES */
}
}
}
STATIC bool is_archive(name)
char *name;
{
/* See if 'name' is the name of an archive file, i.e. it
* should end on ".ma" and should at least be four characters
* long (i.e. the name ".ma" is not accepted as an archive name!).
*/
register char *p;
for (p = name; *p; p++);
return (p > name+3) && (*--p == 'a') && (*--p == 'm') && (*--p == '.');
}
STATIC struct ar_hdr hdr;
STATIC bool read_hdr()
{
/* Read the header of an archive module */
char buf[AR_TOTAL];
register char *c = buf;
register char *p = hdr.ar_name;
register int i;
fread(c, AR_TOTAL, 1, curfile);
if (feof(curfile)) return 0;
i = 14;
while (i--) {
*p++ = *c++;
}
#define get2(c) (((c)[0]&0377) | ((unsigned) ((c)[1]&0377) << 8))
hdr.ar_date = ((long) get2(c)) << 16; c += 2;
hdr.ar_date |= ((long) get2(c)) & 0xffff; c += 2;
hdr.ar_uid = *c++;
hdr.ar_gid = *c++;
hdr.ar_mode = get2(c); c += 2;
hdr.ar_size = (long) get2(c) << 16; c += 2;
hdr.ar_size |= (long) get2(c) & 0xffff;
return 1;
}
STATIC int argcnt = ARGSTART - 1;
STATIC short arstate = NO_ARCHIVE;
FILE *next_file(argc,argv)
int argc;
char *argv[];
{
/* See if there are more EM input files. The file names
* are given via argv. If a file is an archive file
* it is supposed to be a library of EM compact assembly
* files. A module (file) contained in this archive file
* is only used if it imports at least one procedure or
* datalabel for which we have not yet seen a defining
* occurrence, although we have seen a used occurrence.
*/
long ptr;
for (;;) {
/* This loop is only exited via a return */
if (arstate == ARCHIVE) {
/* We were reading an archive file */
if (ftell(curfile) & 1) {
/* modules in an archive file always
* begin on a word boundary, i.e. at
* an even address.
*/
fseek(curfile,1L,1);
}
if (read_hdr()) { /* read header of next module */
ptr = ftell(curfile); /* file position */
file_init(curfile,ARCHIVE,hdr.ar_size);
/* tell i/o package that we're reading
* an archive module of given length.
*/
if (useful()) {
/* re-initialize file, because 'useful'
* has read some bytes too.
*/
fseek(curfile,ptr,0); /* start module */
file_init(curfile,ARCHIVE,hdr.ar_size);
return curfile;
} else {
/* skip this module */
fseek(curfile,
ptr+hdr.ar_size,0);
}
} else {
/* done with this archive */
arstate = NO_ARCHIVE;
}
} else {
/* open next file, close old */
if (curfile != NULL) {
fclose(curfile);
}
argcnt++;
if (argcnt >= argc) {
/* done with all arguments */
return NULL;
}
filename = argv[argcnt];
if ((curfile = fopen(filename,"r")) == NULL) {
error("cannot open %s",filename);
}
if (is_archive(filename)) {
/* ends on '.ma' */
arstate = ARCHIVE;
arch_init(curfile); /* read magic ar number */
} else {
file_init(curfile,NO_ARCHIVE,0L);
return curfile;
}
}
}
}