OS-7261 Want a more modern nawk(1)

Reviewed by: Robert Mustacchi <rm@joyent.com>
Approved by: Jason King <jbk@joyent.com>

usr/src/cmd/awk/DIVERGENCES

@@ -0,0 +1,5 @@
+The illumos nawk(1) is slightly divergent from upstream:
+- We allow an unlimited number of input program files
+- We allow an unlimited number of "/pat/, /pat/" expressions
+- Some of the code has been altered to track the length of strings
+  better so that we can avoid repeatedly calling strlen(3C)

usr/src/cmd/awk/Makefile

@@ -55,7 +55,7 @@ XGETFLAGS += -a -x awk.xcl
 
 CPPFLAGS += -D_FILE_OFFSET_BITS=64
 YFLAGS += -d
-LDLIBS += -lm
+LDLIBS += -lm -lumem
 LINTFLAGS += -u
 CLEANFILES= maketab proctab.c awk.g.c y.tab.h
 

usr/src/cmd/awk/awk.g.y

@@ -55,11 +55,14 @@
 
 %{
 #include "awk.h"
+
+void checkdup(Node *list, Cell *item);
 int yywrap(void) { return(1); }
 
 Node	*beginloc = NULL;
 Node	*endloc = NULL;
-int	infunc	= 0;	        /* = 1 if in arglist or body of func */
+int	infunc	= 0;		/* = 1 if in arglist or body of func */
+int	inloop	= 0;		/* = 1 if in while, for, do */
 char	*curfname = NULL;	/* current function name */
 Node	*arglist = NULL;	/* list of args for current function */
 static void	setfname(Cell *);
@@ -80,10 +83,10 @@ static Node	*notnull(Node *);
 %token	<i>	NL ',' '{' '(' '|' ';' '/' ')' '}' '[' ']'
 %token	<i>	ARRAY
 %token	<i>	MATCH NOTMATCH MATCHOP
-%token	<i>	FINAL DOT ALL CCL NCCL CHAR OR STAR QUEST PLUS
+%token	<i>	FINAL DOT ALL CCL NCCL CHAR OR STAR QUEST PLUS EMPTYRE
 %token	<i>	AND BOR APPEND EQ GE GT LE LT NE IN
 %token	<i>	ARG BLTIN BREAK CLOSE CONTINUE DELETE DO EXIT FOR FUNC
-%token	<i>	SUB GSUB IF INDEX LSUBSTR MATCHFCN NEXT
+%token	<i>	SUB GSUB IF INDEX LSUBSTR MATCHFCN NEXT NEXTFILE
 %token	<i>	ADD MINUS MULT DIVIDE MOD
 %token	<i>	ASSIGN ASGNOP ADDEQ SUBEQ MULTEQ DIVEQ MODEQ POWEQ
 %token	<i>	PRINT PRINTF SPRINTF
@@ -92,13 +95,14 @@ static Node	*notnull(Node *);
 %token	<cp>	VAR IVAR VARNF CALL NUMBER STRING
 %token	<s>	REGEXPR
 
-%type	<p>	pas pattern ppattern plist pplist patlist prarg term
+%type	<p>	pas pattern ppattern plist pplist patlist prarg term re
 %type	<p>	pa_pat pa_stat pa_stats
 %type	<s>	reg_expr
 %type	<p>	simple_stmt opt_simple_stmt stmt stmtlist
 %type	<p>	var varname funcname varlist
-%type	<p>	for if while
-%type	<i>	pst opt_pst lbrace rparen comma nl opt_nl and bor
+%type	<p>	for if else while
+%type	<i>	do st
+%type	<i>	pst opt_pst lbrace rbrace rparen comma nl opt_nl and bor
 %type	<i>	subop print
 
 %right	ASGNOP
@@ -115,7 +119,7 @@ static Node	*notnull(Node *);
 %left	CAT
 %left	'+' '-'
 %left	'*' '/' '%'
-%left	NOT UMINUS
+%left	NOT UMINUS UPLUS
 %right	POWER
 %right	DECR INCR
 %left	INDIRECT
@@ -150,12 +154,12 @@ else:
 	;
 
 for:
-	  FOR '(' opt_simple_stmt ';' pattern ';' opt_simple_stmt rparen stmt
-		{ $$ = stat4(FOR, $3, notnull($5), $7, $9); }
-	| FOR '(' opt_simple_stmt ';'  ';' opt_simple_stmt rparen stmt
-		{ $$ = stat4(FOR, $3, NIL, $6, $8); }
-	| FOR '(' varname IN varname rparen stmt
-		{ $$ = stat3(IN, $3, makearr($5), $7); }
+	  FOR '(' opt_simple_stmt ';' opt_nl pattern ';' opt_nl opt_simple_stmt rparen {inloop++;} stmt
+		{ --inloop; $$ = stat4(FOR, $3, notnull($6), $9, $12); }
+	| FOR '(' opt_simple_stmt ';'  ';' opt_nl opt_simple_stmt rparen {inloop++;} stmt
+		{ --inloop; $$ = stat4(FOR, $3, NIL, $7, $10); }
+	| FOR '(' varname IN varname rparen {inloop++;} stmt
+		{ --inloop; $$ = stat3(IN, $3, makearr($5), $8); }
 	;
 
 funcname:
@@ -203,8 +207,8 @@ pa_pat:
 pa_stat:
 	  pa_pat			{ $$ = stat2(PASTAT, $1, stat2(PRINT, rectonode(), NIL)); }
 	| pa_pat lbrace stmtlist '}'	{ $$ = stat2(PASTAT, $1, $3); }
-	| pa_pat ',' pa_pat		{ $$ = pa2stat($1, $3, stat2(PRINT, rectonode(), NIL)); }
-	| pa_pat ',' pa_pat lbrace stmtlist '}'	{ $$ = pa2stat($1, $3, $5); }
+	| pa_pat ',' opt_nl pa_pat		{ $$ = pa2stat($1, $4, stat2(PRINT, rectonode(), NIL)); }
+	| pa_pat ',' opt_nl pa_pat lbrace stmtlist '}'	{ $$ = pa2stat($1, $4, $6); }
 	| lbrace stmtlist '}'		{ $$ = stat2(PASTAT, NIL, $2); }
 	| XBEGIN lbrace stmtlist '}'
 		{ beginloc = linkum(beginloc, $3); $$ = 0; }
@@ -232,8 +236,6 @@ ppattern:
 		{ $$ = op2(BOR, notnull($1), notnull($3)); }
 	| ppattern and ppattern %prec AND
 		{ $$ = op2(AND, notnull($1), notnull($3)); }
-	| NOT ppattern
-		{ $$ = op1(NOT, notnull($2)); }
 	| ppattern MATCHOP reg_expr	{ $$ = op3($2, NIL, $1, (Node*)makedfa($3, 0)); }
 	| ppattern MATCHOP ppattern
 		{ if (constnode($3))
@@ -243,8 +245,7 @@ ppattern:
 	| ppattern IN varname		{ $$ = op2(INTEST, $1, makearr($3)); }
 	| '(' plist ')' IN varname	{ $$ = op2(INTEST, $2, makearr($5)); }
 	| ppattern term %prec CAT	{ $$ = op2(CAT, $1, $2); }
-	| reg_expr
-		{ $$ = op3(MATCH, NIL, rectonode(), (Node*)makedfa($1, 0)); }
+	| re
 	| term
 	;
 
@@ -256,8 +257,6 @@ pattern:
 		{ $$ = op2(BOR, notnull($1), notnull($3)); }
 	| pattern and pattern %prec AND
 		{ $$ = op2(AND, notnull($1), notnull($3)); }
-	| NOT pattern
-		{ $$ = op1(NOT, op2(NE,$2,celltonode(lookup("$zero&null",symtab),CCON))); }
 	| pattern EQ pattern		{ $$ = op2($2, $1, $3); }
 	| pattern GE pattern		{ $$ = op2($2, $1, $3); }
 	| pattern GT pattern		{ $$ = op2($2, $1, $3); }
@@ -272,11 +271,14 @@ pattern:
 			$$ = op3($2, (Node *)1, $1, $3); }
 	| pattern IN varname		{ $$ = op2(INTEST, $1, makearr($3)); }
 	| '(' plist ')' IN varname	{ $$ = op2(INTEST, $2, makearr($5)); }
-	| pattern '|' GETLINE var	{ $$ = op3(GETLINE, $4, (Node*)$2, $1); }
-	| pattern '|' GETLINE		{ $$ = op3(GETLINE, (Node*)0, (Node*)$2, $1); }
+	| pattern '|' GETLINE var	{
+			if (safe) SYNTAX("cmd | getline is unsafe");
+			else $$ = op3(GETLINE, $4, itonp($2), $1); }
+	| pattern '|' GETLINE		{
+			if (safe) SYNTAX("cmd | getline is unsafe");
+			else $$ = op3(GETLINE, (Node*)0, itonp($2), $1); }
 	| pattern term %prec CAT	{ $$ = op2(CAT, $1, $2); }
-	| reg_expr
-		{ $$ = op3(MATCH, NIL, rectonode(), (Node*)makedfa($1, 0)); }
+	| re
 	| term
 	;
 
@@ -308,6 +310,12 @@ rbrace:
 	  '}' | rbrace NL
 	;
 
+re:
+	   reg_expr
+		{ $$ = op3(MATCH, NIL, rectonode(), (Node*)makedfa($1, 0)); }
+	| NOT re	{ $$ = op1(NOT, notnull($2)); }
+	;
+
 reg_expr:
 	  '/' {startreg();} REGEXPR '/'		{ $$ = $3; }
 	;
@@ -317,12 +325,18 @@ rparen:
 	;
 
 simple_stmt:
-	  print prarg '|' term		{ $$ = stat3($1, $2, (Node *) $3, $4); }
-	| print prarg APPEND term	{ $$ = stat3($1, $2, (Node *) $3, $4); }
-	| print prarg GT term		{ $$ = stat3($1, $2, (Node *) $3, $4); }
+	  print prarg '|' term		{
+			if (safe) SYNTAX("print | is unsafe");
+			else $$ = stat3($1, $2, itonp($3), $4); }
+	| print prarg APPEND term	{
+			if (safe) SYNTAX("print >> is unsafe");
+			else $$ = stat3($1, $2, itonp($3), $4); }
+	| print prarg GT term		{
+			if (safe) SYNTAX("print > is unsafe");
+			else $$ = stat3($1, $2, itonp($3), $4); }
 	| print prarg			{ $$ = stat3($1, $2, NIL, NIL); }
 	| DELETE varname '[' patlist ']' { $$ = stat2(DELETE, makearr($2), $4); }
-	| DELETE varname		{ yyclearin; SYNTAX("you can only delete array[element]"); $$ = stat1(DELETE, $2); }
+	| DELETE varname		{ $$ = stat2(DELETE, makearr($2), 0); }
 	| pattern			{ $$ = exptostat($1); }
 	| error				{ yyclearin; SYNTAX("illegal statement"); }
 	;
@@ -333,11 +347,12 @@ st:
 	;
 
 stmt:
-	  BREAK st		{ $$ = stat1(BREAK, NIL); }
-	| CLOSE pattern st	{ $$ = stat1(CLOSE, $2); }
-	| CONTINUE st		{ $$ = stat1(CONTINUE, NIL); }
-	| do stmt WHILE '(' pattern ')' st
-		{ $$ = stat2(DO, $2, notnull($5)); }
+	  BREAK st		{ if (!inloop) SYNTAX("break illegal outside of loops");
+				  $$ = stat1(BREAK, NIL); }
+	| CONTINUE st		{  if (!inloop) SYNTAX("continue illegal outside of loops");
+				  $$ = stat1(CONTINUE, NIL); }
+	| do {inloop++;} stmt {--inloop;} WHILE '(' pattern ')' st
+		{ $$ = stat2(DO, $3, notnull($7)); }
 	| EXIT pattern st	{ $$ = stat1(EXIT, $2); }
 	| EXIT st		{ $$ = stat1(EXIT, NIL); }
 	| for
@@ -347,10 +362,13 @@ stmt:
 	| NEXT st	{ if (infunc)
 				SYNTAX("next is illegal inside a function");
 			  $$ = stat1(NEXT, NIL); }
+	| NEXTFILE st	{ if (infunc)
+				SYNTAX("nextfile is illegal inside a function");
+			  $$ = stat1(NEXTFILE, NIL); }
 	| RETURN pattern st	{ $$ = stat1(RETURN, $2); }
 	| RETURN st		{ $$ = stat1(RETURN, NIL); }
 	| simple_stmt st
-	| while stmt		{ $$ = stat2(WHILE, $1, $2); }
+	| while {inloop++;} stmt	{ --inloop; $$ = stat2(WHILE, $1, $3); }
 	| ';' opt_nl		{ $$ = 0; }
 	;
 
@@ -372,12 +390,14 @@ term:
 	| term '%' term			{ $$ = op2(MOD, $1, $3); }
 	| term POWER term		{ $$ = op2(POWER, $1, $3); }
 	| '-' term %prec UMINUS		{ $$ = op1(UMINUS, $2); }
-	| '+' term %prec UMINUS		{ $$ = $2; }
+	| '+' term %prec UMINUS		{ $$ = op1(UPLUS, $2); }
+	| NOT term %prec UMINUS		{ $$ = op1(NOT, notnull($2)); }
 	| BLTIN '(' ')'			{ $$ = op2(BLTIN, itonp($1), rectonode()); }
 	| BLTIN '(' patlist ')'		{ $$ = op2(BLTIN, itonp($1), $3); }
 	| BLTIN				{ $$ = op2(BLTIN, itonp($1), rectonode()); }
 	| CALL '(' ')'			{ $$ = op2(CALL, celltonode($1,CVAR), NIL); }
 	| CALL '(' patlist ')'		{ $$ = op2(CALL, celltonode($1,CVAR), $3); }
+	| CLOSE term			{ $$ = op1(CLOSE, $2); }
 	| DECR var			{ $$ = op1(PREDECR, $2); }
 	| INCR var			{ $$ = op1(PREINCR, $2); }
 	| var DECR			{ $$ = op1(POSTDECR, $1); }
@@ -439,7 +459,9 @@ var:
 varlist:
 	  /* nothing */		{ arglist = $$ = 0; }
 	| VAR			{ arglist = $$ = celltonode($1,CVAR); }
-	| varlist comma VAR	{ arglist = $$ = linkum($1,celltonode($3,CVAR)); }
+	| varlist comma VAR	{
+			checkdup($1, $3);
+			arglist = $$ = linkum($1,celltonode($3,CVAR)); }
 	;
 
 varname:
@@ -463,6 +485,7 @@ setfname(Cell *p)
 	else if (isfcn(p))
 		SYNTAX("you can't define function %s more than once", p->nval);
 	curfname = p->nval;
+	p->tval |= FCN;
 }
 
 static int
@@ -488,3 +511,15 @@ notnull(Node *n)
 		return op2(NE, n, nullnode);
 	}
 }
+
+void
+checkdup(Node *vl, Cell *cp)	/* check if name already in list */
+{
+	char *s = cp->nval;
+	for (; vl; vl = vl->nnext) {
+		if (strcmp(s, ((Cell *)(vl->narg[0]))->nval) == 0) {
+			SYNTAX("duplicate argument %s", s);
+			break;
+		}
+	}
+}