[SHELL] Improve LINENO support

This patch improves LINENO support by storing line numbers in the parse
tree, for commands as well as for function definitions. It makes LINENO
behaves properly when calling functions, and has the added benefit of
improved line numbers in error messages when the last-parsed command is
not the last-executed one. It removes the earlier LINENO support, and
instead sets LINENO from evaltree when a command is executed

Signed-off-by: Harald van Dijk <harald@gigawatt.nl>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

13 files changed, 81 insertions, 44 deletions

diff --git a/ChangeLog b/ChangeLog
index 3e7465b..44e5bdf 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,6 +1,7 @@
 2011-03-15  Harald van Dijk <harald@gigawatt.nl>
 
 	* Let funcnode refer to a function definition, not its first command.
+	* Improve LINENO support.
 
 2011-03-15  Brian Koropoff <bkoropoff@gmail.com>
 
diff --git a/src/error.c b/src/error.c
index f1a358d..7ad73bc 100644
--- a/src/error.c
+++ b/src/error.c
@@ -62,6 +62,7 @@ struct jmploc *handler;
 int exception;
 int suppressint;
 volatile sig_atomic_t intpending;
+int errlinno;
 
 
 static void exverror(int, const char *, va_list)
@@ -116,13 +117,12 @@ exvwarning2(const char *msg, va_list ap)
 	const char *fmt;
 
 	errs = out2;
-	name = arg0 ?: "sh";
-	fmt = "%s: ";
-	if (commandname) {
-		name = commandname;
+	name = arg0 ? arg0 : "sh";
+	if (!commandname)
 		fmt = "%s: %d: ";
-	}
-	outfmt(errs, fmt, name, startlinno);
+	else
+		fmt = "%s: %d: %s: ";
+	outfmt(errs, fmt, name, errlinno, commandname);
 	doformat(errs, msg, ap);
 #if FLUSHERR
 	outc('\n', errs);
diff --git a/src/error.h b/src/error.h
index f236d9f..9630b56 100644
--- a/src/error.h
+++ b/src/error.h
@@ -120,6 +120,7 @@ void onint(void) __attribute__((__noreturn__));
 #else
 void onint(void);
 #endif
+extern int errlinno;
 void sh_error(const char *, ...) __attribute__((__noreturn__));
 void exerror(int, const char *, ...) __attribute__((__noreturn__));
 const char *errmsg(int, int);
diff --git a/src/eval.c b/src/eval.c
index 9f4388a..426c03a 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -73,7 +73,7 @@
 int evalskip;			/* set if we are skipping commands */
 STATIC int skipcount;		/* number of levels to skip */
 MKINIT int loopnest;		/* current loop nesting level */
-static int funcnest;		/* depth of function calls */
+static int funcline;		/* starting line number of current function, or 0 if not in a function */
 
 
 char *commandname;
@@ -218,6 +218,9 @@ evaltree(union node *n, int flags)
 		status = !exitstatus;
 		goto setstatus;
 	case NREDIR:
+		errlinno = lineno = n->nredir.linno;
+		if (funcline)
+			lineno -= funcline - 1;
 		expredir(n->nredir.redirect);
 		pushredir(n->nredir.redirect);
 		status = redirectsafe(n->nredir.redirect, REDIR_PUSH);
@@ -376,6 +379,10 @@ evalfor(union node *n, int flags)
 	struct strlist *sp;
 	struct stackmark smark;
 
+	errlinno = lineno = n->nfor.linno;
+	if (funcline)
+		lineno -= funcline - 1;
+
 	setstackmark(&smark);
 	arglist.lastp = &arglist.list;
 	for (argp = n->nfor.args ; argp ; argp = argp->narg.next) {
@@ -417,6 +424,10 @@ evalcase(union node *n, int flags)
 	struct arglist arglist;
 	struct stackmark smark;
 
+	errlinno = lineno = n->ncase.linno;
+	if (funcline)
+		lineno -= funcline - 1;
+
 	setstackmark(&smark);
 	arglist.lastp = &arglist.list;
 	expandarg(n->ncase.expr, &arglist, EXP_TILDE);
@@ -448,6 +459,10 @@ evalsubshell(union node *n, int flags)
 	int backgnd = (n->type == NBACKGND);
 	int status;
 
+	errlinno = lineno = n->nredir.linno;
+	if (funcline)
+		lineno -= funcline - 1;
+
 	expredir(n->nredir.redirect);
 	if (!backgnd && flags & EV_EXIT && !have_traps())
 		goto nofork;
@@ -704,6 +719,10 @@ evalcommand(union node *cmd, int flags)
 	int status;
 	char **nargv;
 
+	errlinno = lineno = cmd->ncmd.linno;
+	if (funcline)
+		lineno -= funcline - 1;
+
 	/* First expand the arguments. */
 	TRACE(("evalcommand(0x%lx, %d) called\n", (long)cmd, flags));
 	setstackmark(&smark);
@@ -737,7 +756,7 @@ evalcommand(union node *cmd, int flags)
 	*nargv = NULL;
 
 	lastarg = NULL;
-	if (iflag && funcnest == 0 && argc > 0)
+	if (iflag && funcline == 0 && argc > 0)
 		lastarg = nargv[-1];
 
 	preverrout.fd = 2;
@@ -937,8 +956,10 @@ evalfun(struct funcnode *func, int argc, char **argv, int flags)
 	struct jmploc *volatile savehandler;
 	struct jmploc jmploc;
 	int e;
+	int savefuncline;
 
 	saveparam = shellparam;
+	savefuncline = funcline;
 	if ((e = setjmp(jmploc.loc))) {
 		goto funcdone;
 	}
@@ -947,18 +968,18 @@ evalfun(struct funcnode *func, int argc, char **argv, int flags)
 	handler = &jmploc;
 	shellparam.malloc = 0;
 	func->count++;
-	funcnest++;
+	funcline = func->n.ndefun.linno;
 	INTON;
 	shellparam.nparam = argc - 1;
 	shellparam.p = argv + 1;
 	shellparam.optind = 1;
 	shellparam.optoff = -1;
 	pushlocalvars();
-	evaltree(func->n.narg.next, flags & EV_TESTED);
+	evaltree(func->n.ndefun.body, flags & EV_TESTED);
 	poplocalvars(0);
 funcdone:
 	INTOFF;
-	funcnest--;
+	funcline = savefuncline;
 	freefunc(func);
 	freeparam(&shellparam);
 	shellparam = saveparam;
@@ -1048,7 +1069,7 @@ returncmd(int argc, char **argv)
 	 * If called outside a function, do what ksh does;
 	 * skip the rest of the file.
 	 */
-	evalskip = funcnest ? SKIPFUNC : SKIPFILE;
+	evalskip = funcline ? SKIPFUNC : SKIPFILE;
 	return argv[1] ? number(argv[1]) : exitstatus;
 }
 
diff --git a/src/exec.c b/src/exec.c
index a13ad67..79e2007 100644
--- a/src/exec.c
+++ b/src/exec.c
@@ -697,7 +697,7 @@ defun(union node *func)
 	INTOFF;
 	entry.cmdtype = CMDFUNCTION;
 	entry.u.func = copyfunc(func);
-	addcmdentry(func->narg.text, &entry);
+	addcmdentry(func->ndefun.text, &entry);
 	INTON;
 }
 
diff --git a/src/input.c b/src/input.c
index bd3a9a2..d31c45b 100644
--- a/src/input.c
+++ b/src/input.c
@@ -54,7 +54,6 @@
 #include "alias.h"
 #include "parser.h"
 #include "main.h"
-#include "var.h"
 #ifndef SMALL
 #include "myhistedit.h"
 #endif
@@ -531,12 +530,3 @@ closescript(void)
 		parsefile->fd = 0;
 	}
 }
-
-
-int lineno_inc(void)
-{
-	int lineno = plinno++;
-
-	setvarint("LINENO", lineno, 0);
-	return lineno;
-}
diff --git a/src/input.h b/src/input.h
index bdf8857..50a7797 100644
--- a/src/input.h
+++ b/src/input.h
@@ -61,7 +61,6 @@ void setinputstring(char *);
 void popfile(void);
 void popallfiles(void);
 void closescript(void);
-int lineno_inc(void);
 
 #define pgetc_macro() \
 	(--parsenleft >= 0 ? (signed char)*parsenextc++ : preadbuffer())
diff --git a/src/jobs.c b/src/jobs.c
index 4b1b938..bf40204 100644
--- a/src/jobs.c
+++ b/src/jobs.c
@@ -1288,7 +1288,7 @@ dotail:
 		p = "; done";
 		goto dodo;
 	case NDEFUN:
-		cmdputs(n->narg.text);
+		cmdputs(n->ndefun.text);
 		p = "() { ... }";
 		goto dotail2;
 	case NCMD:
diff --git a/src/nodetypes b/src/nodetypes
index 17a7b3c..ceaf478 100644
--- a/src/nodetypes
+++ b/src/nodetypes
@@ -51,6 +51,7 @@
 
 NCMD ncmd			# a simple command
 	type	  int
+	linno	  int
 	assign    nodeptr		# variable assignments
 	args	  nodeptr		# the arguments
 	redirect  nodeptr		# list of file redirections
@@ -62,6 +63,7 @@ NPIPE npipe			# a pipeline
 
 NREDIR nredir			# redirection (of a complex command)
 	type	  int
+	linno	  int
 	n	  nodeptr		# the command
 	redirect  nodeptr		# list of file redirections
 
@@ -87,12 +89,14 @@ NUNTIL nbinary			# the until statement
 
 NFOR nfor			# the for statement
 	type	  int
+	linno	  int
 	args	  nodeptr		# for var in args
 	body	  nodeptr		# do body; done
 	var	  string		# the for variable
 
 NCASE ncase			# a case statement
 	type	  int
+	linno	  int
 	expr	  nodeptr		# the word to switch on
 	cases	  nodeptr		# the list of cases (NCLIST nodes)
 
@@ -103,8 +107,11 @@ NCLIST nclist			# a case
 	body	  nodeptr		# code to execute for this case
 
 
-NDEFUN narg			# define a function.  The "next" field contains
-				# the body of the function.
+NDEFUN ndefun			# a function
+	type	  int
+	linno	  int
+	text	  string
+	body	  nodeptr
 
 NARG narg			# represents a word
 	type	  int
diff --git a/src/parser.c b/src/parser.c
index be20ff7..0bfd620 100644
--- a/src/parser.c
+++ b/src/parser.c
@@ -93,7 +93,6 @@ struct nodelist *backquotelist;
 union node *redirnode;
 struct heredoc *heredoc;
 int quoteflag;			/* set if (part of) last token was quoted */
-int startlinno;			/* line # where last token started */
 
 
 STATIC union node *list(int);
@@ -304,10 +303,13 @@ command(void)
 	union node *redir, **rpp;
 	union node **rpp2;
 	int t;
+	int savelinno;
 
 	redir = NULL;
 	rpp2 = &redir;
 
+	savelinno = plinno;
+
 	switch (readtoken()) {
 	default:
 		synexpect(-1);
@@ -356,6 +358,7 @@ TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
 			synerror("Bad for loop variable");
 		n1 = (union node *)stalloc(sizeof (struct nfor));
 		n1->type = NFOR;
+		n1->nfor.linno = savelinno;
 		n1->nfor.var = wordtext;
 		checkkwd = CHKNL | CHKKWD | CHKALIAS;
 		if (readtoken() == TIN) {
@@ -395,6 +398,7 @@ TRACE(("expecting DO got %s %s\n", tokname[got], got == TWORD ? wordtext : ""));
 	case TCASE:
 		n1 = (union node *)stalloc(sizeof (struct ncase));
 		n1->type = NCASE;
+		n1->ncase.linno = savelinno;
 		if (readtoken() != TWORD)
 			synexpect(TWORD);
 		n1->ncase.expr = n2 = (union node *)stalloc(sizeof (struct narg));
@@ -445,6 +449,7 @@ next_case:
 	case TLP:
 		n1 = (union node *)stalloc(sizeof (struct nredir));
 		n1->type = NSUBSHELL;
+		n1->nredir.linno = savelinno;
 		n1->nredir.n = list(0);
 		n1->nredir.redirect = NULL;
 		t = TRP;
@@ -477,6 +482,7 @@ redir:
 		if (n1->type != NSUBSHELL) {
 			n2 = (union node *)stalloc(sizeof (struct nredir));
 			n2->type = NREDIR;
+			n2->nredir.linno = savelinno;
 			n2->nredir.n = n1;
 			n1 = n2;
 		}
@@ -494,6 +500,7 @@ simplecmd(void) {
 	union node *vars, **vpp;
 	union node **rpp, *redir;
 	int savecheckkwd;
+	int savelinno;
 
 	args = NULL;
 	app = &args;
@@ -503,6 +510,7 @@ simplecmd(void) {
 	rpp = &redir;
 
 	savecheckkwd = CHKALIAS;
+	savelinno = plinno;
 	for (;;) {
 		checkkwd = savecheckkwd;
 		switch (readtoken()) {
@@ -546,7 +554,9 @@ simplecmd(void) {
 					synerror("Bad function name");
 				n->type = NDEFUN;
 				checkkwd = CHKNL | CHKKWD | CHKALIAS;
-				n->narg.next = command();
+				n->ndefun.text = n->narg.text;
+				n->ndefun.linno = plinno;
+				n->ndefun.body = command();
 				return n;
 			}
 			/* fall through */
@@ -561,6 +571,7 @@ out:
 	*rpp = NULL;
 	n = (union node *)stalloc(sizeof (struct ncmd));
 	n->type = NCMD;
+	n->ncmd.linno = savelinno;
 	n->ncmd.args = args;
 	n->ncmd.assign = vars;
 	n->ncmd.redirect = redir;
@@ -738,8 +749,6 @@ out:
  *	quoted.
  * If the token is TREDIR, then we set redirnode to a structure containing
  *	the redirection.
- * In all cases, the variable startlinno is set to the number of the line
- *	on which the token starts.
  *
  * [Change comment:  here documents and internal procedures]
  * [Readtoken shouldn't have any arguments.  Perhaps we should make the
@@ -763,7 +772,6 @@ xxreadtoken(void)
 	if (needprompt) {
 		setprompt(2);
 	}
-	startlinno = plinno;
 	for (;;) {	/* until token or start of word found */
 		c = pgetc_macro();
 		switch (c) {
@@ -776,7 +784,7 @@ xxreadtoken(void)
 			continue;
 		case '\\':
 			if (pgetc() == '\n') {
-				startlinno = lineno_inc();
+				plinno++;
 				if (doprompt)
 					setprompt(2);
 				continue;
@@ -784,7 +792,7 @@ xxreadtoken(void)
 			pungetc();
 			goto breakloop;
 		case '\n':
-			lineno_inc();
+			plinno++;
 			needprompt = doprompt;
 			RETURN(TNL);
 		case PEOF:
@@ -855,7 +863,6 @@ readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
 	/* syntax before arithmetic */
 	char const *uninitialized_var(prevsyntax);
 
-	startlinno = plinno;
 	dblquote = 0;
 	if (syntax == DQSYNTAX)
 		dblquote = 1;
@@ -886,7 +893,7 @@ readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
 				if (syntax == BASESYNTAX)
 					goto endword;	/* exit outer loop */
 				USTPUTC(c, out);
-				lineno_inc();
+				plinno++;
 				if (doprompt)
 					setprompt(2);
 				c = pgetc();
@@ -907,6 +914,7 @@ readtoken1(int firstc, char const *syntax, char *eofmark, int striptabs)
 					USTPUTC('\\', out);
 					pungetc();
 				} else if (c == '\n') {
+					plinno++;
 					if (doprompt)
 						setprompt(2);
 				} else {
@@ -1008,7 +1016,6 @@ endword:
 	if (syntax != BASESYNTAX && eofmark == NULL)
 		synerror("Unterminated quoted string");
 	if (varnest != 0) {
-		startlinno = plinno;
 		/* { */
 		synerror("Missing '}'");
 	}
@@ -1065,7 +1072,7 @@ checkend: {
 
 		if (c == '\n' || c == PEOF) {
 			c = PEOF;
-			lineno_inc();
+			plinno++;
 			needprompt = doprompt;
 		} else {
 			int len;
@@ -1315,7 +1322,7 @@ parsebackq: {
 
 			case '\\':
                                 if ((pc = pgetc()) == '\n') {
-					lineno_inc();
+					plinno++;
 					if (doprompt)
 						setprompt(2);
 					/*
@@ -1336,11 +1343,10 @@ parsebackq: {
 
 			case PEOF:
 			case PEOA:
-			        startlinno = plinno;
 				synerror("EOF in backquote substitution");
 
 			case '\n':
-				lineno_inc();
+				plinno++;
 				needprompt = doprompt;
 				break;
 
@@ -1472,6 +1478,7 @@ synexpect(int token)
 STATIC void
 synerror(const char *msg)
 {
+	errlinno = plinno;
 	sh_error("Syntax error: %s", msg);
 	/* NOTREACHED */
 }
diff --git a/src/parser.h b/src/parser.h
index 6bdf1c9..e6caed6 100644
--- a/src/parser.h
+++ b/src/parser.h
@@ -77,7 +77,6 @@ extern int tokpushback;
 #define NEOF ((union node *)&tokpushback)
 extern int whichprompt;		/* 1 == PS1, 2 == PS2 */
 extern int checkkwd;
-extern int startlinno;		/* line # where last token started */
 
 
 union node *parsecmd(int);
diff --git a/src/var.c b/src/var.c
index aec1076..ecc8c90 100644
--- a/src/var.c
+++ b/src/var.c
@@ -33,6 +33,7 @@
  */
 
 #include <unistd.h>
+#include <stdio.h>
 #include <stdlib.h>
 #ifdef HAVE_PATHS_H
 #include <paths.h>
@@ -80,6 +81,9 @@ const char defifsvar[] = "IFS= \t\n";
 const char defifs[] = " \t\n";
 #endif
 
+int lineno;
+char linenovar[sizeof("LINENO=")+sizeof(int)*CHAR_BIT/3+1] = "LINENO=";
+
 /* Some macros in var.h depend on the order, add new variables to the end. */
 struct var varinit[] = {
 #if ATTY
@@ -97,11 +101,11 @@ struct var varinit[] = {
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"PS2=> ",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"PS4=+ ",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED,		"OPTIND=1",	getoptsreset },
+	{ 0,	VSTRFIXED|VTEXTFIXED,		linenovar,	0 },
 #ifndef SMALL
 	{ 0,	VSTRFIXED|VTEXTFIXED|VUNSET,	"TERM\0",	0 },
 	{ 0,	VSTRFIXED|VTEXTFIXED|VUNSET,	"HISTSIZE\0",	sethistsize },
 #endif
-	{ 0,	VSTRFIXED|VTEXTFIXED,		"LINENO=1",	0 },
 };
 
 STATIC struct var *vartab[VTABSIZE];
@@ -331,6 +335,9 @@ lookupvar(const char *name)
 	struct var *v;
 
 	if ((v = *findvar(hashvar(name), name)) && !(v->flags & VUNSET)) {
+		if (v == &vlineno && v->text == linenovar) {
+			fmtstr(linenovar+7, sizeof(linenovar)-7, "%d", lineno);
+		}
 		return strchrnul(v->text, '=') + 1;
 	}
 	return NULL;
diff --git a/src/var.h b/src/var.h
index 35dd099..54f7b2d 100644
--- a/src/var.h
+++ b/src/var.h
@@ -88,8 +88,9 @@ extern struct var varinit[];
 #define vps2 (&vps1)[1]
 #define vps4 (&vps2)[1]
 #define voptind (&vps4)[1]
+#define vlineno (&voptind)[1]
 #ifndef SMALL
-#define vterm (&voptind)[1]
+#define vterm (&vlineno)[1]
 #define vhistsize (&vterm)[1]
 #endif
 
@@ -102,6 +103,9 @@ extern const char defifs[];
 extern const char defpathvar[];
 #define defpath (defpathvar + 5)
 
+extern int lineno;
+extern char linenovar[];
+
 /*
  * The following macros access the values of the above variables.
  * They have to skip over the name.  They return the null string
@@ -117,6 +121,7 @@ extern const char defpathvar[];
 #define ps2val()	(vps2.text + 4)
 #define ps4val()	(vps4.text + 4)
 #define optindval()	(voptind.text + 7)
+#define linenoval()	(vlineno.text + 7)
 #ifndef SMALL
 #define histsizeval()	(vhistsize.text + 9)
 #define termval()	(vterm.text + 5)