sources-request@mirror.UUCP (09/11/86)
Submitted by: linus!gatech!emoryu1!emoryu2!arnold (Arnold D. Robbins)
Mod.sources: Volume 7, Issue 23
Archive-name: 4.3cpp.patch
[ This is a modification of the V6#44 cpp.patch for 4.3BSD. --r$ ]
Basically, with these patches are installed, /lib/cpp gains two new
capabilities: The #elif found in recent versions of System V and in the
draft ANSI standard, and the ability to recognize C++ // comments,
which start with the // delimiter, and go to the end of the line.
#elif is automatic: it is fast becoming a standard C feature, and I
feel that everyone would want it. // comments require that the new -B
option be given, for their recognition to be turned on. Sites with C++
should modify their CC shell script to call /lib/cpp with this option.
(I chose -B as sort of mnemonic for the BCPL programming language, from
which // was re-instituted.)
Credits: Doug Gwyn of BRL implemented #elif for his System V emulation;
however I typed it in to make the "style" consistent; all typos are
mine. I wrote the // processing code. Enjoy.
Unpack this file and feed it to patch while in a cpp source directory,
then run make / "make install".
--------------------CUT HERE--------------------
*** cpp.c.orig Mon Aug 11 17:58:06 1986
--- cpp.c Mon Aug 11 17:50:28 1986
***************
*** 1,4 ****
--- 1,24 ----
#ifndef lint
+ static char *RCSid = "$Header: cpp.c,v 1.3 86/08/11 17:49:38 root Locked $";
+ #endif
+
+ /*
+ * $Log: cpp.c,v $
+ * Revision 1.3 86/08/11 17:49:38 root
+ * Bug fix to #elif stuff due to a typo. Fixed new code to call sayline()
+ * with an argument. ADR.
+ *
+ * Revision 1.2 86/08/07 17:55:56 root
+ * Added Doug Gwyn's code to handle #elif. This is always on. Also
+ * added my code that takes a -B option, to recognize C++ // ... \n
+ * style of comments. ADR.
+ *
+ * Revision 1.1 86/08/07 16:15:52 root
+ * Initial revision
+ *
+ */
+
+ #ifndef lint
static char sccsid[] = "@(#)cpp.c 1.14 4/27/86";
#endif lint
***************
*** 153,158 ****
--- 173,179 ----
STATIC int nd = 1;
STATIC int pflag; /* don't put out lines "# 12 foo.c" */
int passcom; /* don't delete comments */
+ int eolcom; /* allow // ... \n comments */
int incomment; /* True if parsing a comment */
STATIC int rflag; /* allow macro recursion */
STATIC int mflag; /* generate makefile dependencies */
***************
*** 192,197 ****
--- 213,219 ----
STATIC struct symtab *udfloc;
STATIC struct symtab *incloc;
STATIC struct symtab *ifloc;
+ STATIC struct symtab *eliloc; /* DAG -- added */
STATIC struct symtab *elsloc;
STATIC struct symtab *eifloc;
STATIC struct symtab *ifdloc;
***************
*** 204,209 ****
--- 226,233 ----
STATIC struct symtab *identloc; /* Sys 5r3 compatibility */
STATIC int trulvl;
STATIC int flslvl;
+ #define MAX_IF_NESTING 64 /* DAG -- added (must be at least6) */
+ STATIC int ifdone[MAX_IF_NESTING]; /* DAG -- added */
sayline(where)
int where;
***************
*** 393,402 ****
else {++p; break;}
} break;
case '/': for (;;) {
! if (*p++=='*') {/* comment */
incomment++;
if (!passcom) {inp=p-2; dump(); ++flslvl;}
for (;;) {
while (!iscom(*p++));
if (p[-1]=='*') for (;;) {
if (*p++=='/') goto endcom;
--- 417,448 ----
else {++p; break;}
} break;
case '/': for (;;) {
! if (*p=='/' && eolcom) {
! p++;
incomment++;
if (!passcom) {inp=p-2; dump(); ++flslvl;}
for (;;) {
+ while (*p && *p++ != '\n');
+ if (p[-1]=='\n') {
+ p--;
+ goto endcpluscom;
+ } else if (eob(--p)) {
+ if(!passcom) {inp=p; p=refill(p);}
+ else if ((p-inp) >= BUFSIZ) {/* split long comment */
+ inp=p; refill(p);
+ } else p=refill(p);
+ } else ++p; /* ignore null byte */
+ }
+ endcpluscom:
+ if (!passcom) {outp=inp=p; --flslvl;}
+ incomment--;
+ goto newline;
+ break;
+ }
+ else if (*p++=='*') {/* comment */
+ incomment++;
+ if (!passcom) {inp=p-2; dump(); ++flslvl;}
+ for (;;) {
while (!iscom(*p++));
if (p[-1]=='*') for (;;) {
if (*p++=='/') goto endcom;
***************
*** 446,451 ****
--- 492,498 ----
}
} break;
case '\n': {
+ newline:
++lineno[ifno]; if (isslo) {state=LF; return(p);}
prevlf:
state=BEG;
***************
*** 746,752 ****
#define fasscan() ptrtab=fastab+COFF
#define sloscan() ptrtab=slotab+COFF
! char *
control(p) register char *p; {/* find and handle preprocessor control lines */
register struct symtab *np;
for (;;) {
--- 793,799 ----
#define fasscan() ptrtab=fastab+COFF
#define sloscan() ptrtab=slotab+COFF
! void /* DAG -- bug fix (was (char *)) */
control(p) register char *p; {/* find and handle preprocessor control lines */
register struct symtab *np;
for (;;) {
***************
*** 759,777 ****
if (flslvl==0) {p=doincl(p); continue;}
} else if (np==ifnloc) {/* ifndef */
++flslvl; p=skipbl(p); np=slookup(inp,p,0); --flslvl;
! if (flslvl==0 && np->value==0) ++trulvl;
else ++flslvl;
} else if (np==ifdloc) {/* ifdef */
++flslvl; p=skipbl(p); np=slookup(inp,p,0); --flslvl;
! if (flslvl==0 && np->value!=0) ++trulvl;
else ++flslvl;
} else if (np==eifloc) {/* endif */
if (flslvl) {if (--flslvl==0) sayline(CONT);}
! else if (trulvl) --trulvl;
else pperror("If-less endif",0);
} else if (np==elsloc) {/* else */
if (flslvl) {
! if (--flslvl!=0) ++flslvl;
else {++trulvl; sayline(CONT);}
}
else if (trulvl) {++flslvl; --trulvl;}
--- 806,832 ----
if (flslvl==0) {p=doincl(p); continue;}
} else if (np==ifnloc) {/* ifndef */
++flslvl; p=skipbl(p); np=slookup(inp,p,0); --flslvl;
! if (flslvl==0)
! if(ifdone[trulvl] = np->value==0)
! ++trulvl;
! else
! ++flslvl;
else ++flslvl;
} else if (np==ifdloc) {/* ifdef */
++flslvl; p=skipbl(p); np=slookup(inp,p,0); --flslvl;
! if (flslvl==0)
! if (ifdone[trulvl] = np->value!=0)
! ++trulvl;
! else
! ++flslvl;
else ++flslvl;
} else if (np==eifloc) {/* endif */
if (flslvl) {if (--flslvl==0) sayline(CONT);}
! else if (trulvl) ifdone[--trulvl] = 0; /* DAG */
else pperror("If-less endif",0);
} else if (np==elsloc) {/* else */
if (flslvl) {
! if (--flslvl!=0 || ifdone[trulvl]) ++flslvl;
else {++trulvl; sayline(CONT);}
}
else if (trulvl) {++flslvl; --trulvl;}
***************
*** 783,794 ****
} else if (np==ifloc) {/* if */
#if tgp
pperror(" IF not implemented, true assumed", 0);
! if (flslvl==0) ++trulvl; else ++flslvl;
#else
newp=p;
! if (flslvl==0 && yyparse()) ++trulvl; else ++flslvl;
p=newp;
#endif
} else if (np==lneloc) {/* line */
if (flslvl==0 && pflag==0) {
char *savestring();
--- 838,897 ----
} else if (np==ifloc) {/* if */
#if tgp
pperror(" IF not implemented, true assumed", 0);
! if (flslvl==0) ifdone[trulvl++] = 1; else ++flslvl;
#else
newp=p;
! if (flslvl==0)
! {
! if (ifdone[trulvl] = yyparse()) /* DAG */
! ++trulvl;
! else
! ++flslvl;
! }
! else ++flslvl;
p=newp;
#endif
+ } else if (np==eliloc) {/* elif */ /* DAG -- added */
+ #if tgp
+ pperror (" ELIF not implemented, true assumed", (char *) 0, (char *) 0);
+ if (flslvl)
+ {
+ if (--flslvl == 0 && !ifdone[trulvl])
+ {
+ ifdone[trulvl++] = 1;
+ sayline (CONT);
+ }
+ else
+ ++flslvl;
+ }
+ else if (trulvl)
+ {
+ ++flslvl;
+ --trulvl;
+ }
+ else
+ pperror ( "If-less elif", (char *) 0, (char *) 0);
+ #else
+ newp = p;
+ if (flslvl)
+ {
+ if (--flslvl == 0 && !ifdone[trulvl] && yyparse ())
+ {
+ ifdone[trulvl++] = 1;
+ sayline (CONT);
+ }
+ else
+ ++flslvl;
+ }
+ else if (trulvl)
+ {
+ ++flslvl;
+ --trulvl;
+ }
+ else
+ pperror ( "If-less elif", (char *) 0, (char *) 0);
+ p = newp;
+ #endif
} else if (np==lneloc) {/* line */
if (flslvl==0 && pflag==0) {
char *savestring();
***************
*** 1137,1142 ****
--- 1240,1246 ----
case 'E': continue;
case 'R': ++rflag; continue;
case 'C': passcom++; continue;
+ case 'B': eolcom++; continue;
case 'D':
if (predef>prespc+NPREDEF) {
pperror("too many -D options, ignoring %s",argv[i]);
***************
*** 1235,1240 ****
--- 1339,1345 ----
ifdloc=ppsym("ifdef");
ifnloc=ppsym("ifndef");
ifloc=ppsym("if");
+ eliloc=ppsym("elif");
lneloc=ppsym("line");
identloc=ppsym("ident"); /* Sys 5r3 compatibility */
for (i=sizeof(macbit)/sizeof(macbit[0]); --i>=0; ) macbit[i]=0;