Add min_required and max_expected arg counts to API.

16 files changed, 108 insertions, 113 deletions

diff --git a/ChangeLog b/ChangeLog
index b3f33633..df8f9197 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,17 @@
+2016-12-06         Arnold D. Robbins     <arnold@skeeve.com>
+
+	Add minimum required and maximum expected number of arguments
+	to the API.
+
+	* awk.h (INSTRUCTION): Add new members min_required and max_expected.
+	* ext.c (make_builtin): Store values from extension function struct
+	into the INSTRUCTION.
+	* gawkapi.h (awk_ext_func): Add min_required args. Make both it and
+	max_expected_args into unsigned short to match type in INSTRUCTION.
+	* interpret.h (Op_ext_builtin): Store min_required and max_expected
+	in instructions. Add checking code and lint checks.
+	(Op_ext_func): Copy min_required and max_expected from function info.
+
 2016-11-30         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* dfa.c: Sync with fixes in GNULIB.
diff --git a/awk.h b/awk.h
index 55746927..4f04fc83 100644
--- a/awk.h
+++ b/awk.h
@@ -778,6 +778,10 @@ typedef struct exp_instruction {
 		void (*aptr)(void);
 		struct exp_instruction *xi;
 		struct break_point *bpt;
+		struct {
+			uint16_t mr;	// minimum required
+			uint16_t me;	// maximum expected
+		} fa;	// function args
 	} x;
 
 	short source_line;
@@ -793,6 +797,9 @@ typedef struct exp_instruction {
 
 #define expr_count      x.xl
 
+#define min_required	x.fa.mr
+#define max_expected	x.fa.me
+
 #define target_continue d.di
 #define target_jmp      d.di
 #define target_break    x.xi
diff --git a/ext.c b/ext.c
index 10a42210..b6447c5a 100644
--- a/ext.c
+++ b/ext.c
@@ -136,7 +136,8 @@ make_builtin(const awk_ext_func_t *funcinfo)
 
 	b = bcalloc(Op_symbol, 1, 0);
 	b->extfunc = funcinfo->function;
-	b->expr_count = count;
+	b->min_required = funcinfo->min_required_args;
+	b->max_expected = funcinfo->max_expected_args;
 
 	/* NB: extension sub must return something */
 
diff --git a/extension/ChangeLog b/extension/ChangeLog
index 52d4ddb5..845391f9 100644
--- a/extension/ChangeLog
+++ b/extension/ChangeLog
@@ -1,3 +1,20 @@
+2016-12-06         Arnold D. Robbins     <arnold@skeeve.com>
+
+	Add minimum required and maximum expected number of arguments
+	to the API.
+
+	* filefuncs.c: Update with max expected value. Remove lint
+	checks since that's now done by gawk.
+	* fnmatch.c: Ditto.
+	* fork.c: Ditto.
+	* inplace.c: Ditto.
+	* ordchr.c: Ditto.
+	* readfile.c: Ditto.
+	* rwarray.c: Ditto.
+	* rwarray0.c: Ditto.
+	* testext.c: Ditto.
+	* time.c: Ditto.
+
 2016-10-23         Arnold D. Robbins     <arnold@skeeve.com>
 
 	* General: Remove trailing whitespace from all relevant files.
diff --git a/extension/filefuncs.c b/extension/filefuncs.c
index a074de53..02b40534 100644
--- a/extension/filefuncs.c
+++ b/extension/filefuncs.c
@@ -160,9 +160,6 @@ do_chdir(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs != 1)
-		lintwarn(ext_id, _("chdir: called with incorrect number of arguments, expecting 1"));
-
 	if (get_argument(0, AWK_STRING, & newdir)) {
 		ret = chdir(newdir.str_value.str);
 		if (ret < 0)
@@ -472,12 +469,6 @@ do_stat(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (nargs != 2 && nargs != 3) {
-		if (do_lint)
-			lintwarn(ext_id, _("stat: called with wrong number of arguments"));
-		return make_number(-1, result);
-	}
-
 	/* file is first arg, array to hold results is second */
 	if (   ! get_argument(0, AWK_STRING, & file_param)
 	    || ! get_argument(1, AWK_ARRAY, & array_param)) {
@@ -522,12 +513,6 @@ do_statvfs(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (nargs != 2) {
-		if (do_lint)
-			lintwarn(ext_id, _("statvfs: called with wrong number of arguments"));
-		return make_number(-1, result);
-	}
-
 	/* file is first arg, array to hold results is second */
 	if (   ! get_argument(0, AWK_STRING, & file_param)
 	    || ! get_argument(1, AWK_ARRAY, & array_param)) {
@@ -845,7 +830,7 @@ do_fts(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	fts_errors = 0;		/* ensure a fresh start */
 
-	if (do_lint && nargs != 3)
+	if (nargs > 3)
 		lintwarn(ext_id, _("fts: called with incorrect number of arguments, expecting 3"));
 
 	if (! get_argument(0, AWK_ARRAY, & pathlist)) {
@@ -928,13 +913,13 @@ out:
 #endif	/* ! __MINGW32__ */
 
 static awk_ext_func_t func_table[] = {
-	{ "chdir",	do_chdir, 1 },
-	{ "stat",	do_stat, 3 },
+	{ "chdir",	do_chdir, 1, 1 },
+	{ "stat",	do_stat, 2, 3 },
 #ifndef __MINGW32__
-	{ "fts",	do_fts, 3 },
+	{ "fts",	do_fts, 3, 3 },
 #endif
 #if defined(HAVE_SYS_STATVFS_H) && defined(HAVE_STATVFS)
-	{ "statvfs",	do_statvfs, 2 },
+	{ "statvfs",	do_statvfs, 2, 2 },
 #endif
 };
 
diff --git a/extension/fnmatch.c b/extension/fnmatch.c
index f5fb02c6..caf64a7b 100644
--- a/extension/fnmatch.c
+++ b/extension/fnmatch.c
@@ -107,13 +107,8 @@ do_fnmatch(int nargs, awk_value_t *result)
 	int int_flags, retval;
 
 	make_number(-1.0, result);	/* default return */
-#ifdef HAVE_FNMATCH
-	if (nargs < 3) {
-		warning(ext_id, _("fnmatch: called with less than three arguments"));
-		goto out;
-	} else if (do_lint && nargs > 3)
-		lintwarn(ext_id, _("fnmatch: called with more than three arguments"));
 
+#ifdef HAVE_FNMATCH
 	if (! get_argument(0, AWK_STRING, & pattern)) {
 		warning(ext_id, _("fnmatch: could not get first argument"));
 		goto out;
@@ -199,7 +194,7 @@ init_fnmatch(void)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "fnmatch", do_fnmatch, 3 },
+	{ "fnmatch", do_fnmatch, 3, 3 },
 };
 
 /* define the dl_load function using the boilerplate macro */
diff --git a/extension/fork.c b/extension/fork.c
index 82593b7f..064a2a8c 100644
--- a/extension/fork.c
+++ b/extension/fork.c
@@ -77,9 +77,6 @@ do_fork(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 0)
-		lintwarn(ext_id, _("fork: called with too many arguments"));
-
 	ret = fork();
 
 	if (ret < 0)
@@ -114,16 +111,12 @@ do_waitpid(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 1)
-		lintwarn(ext_id, _("waitpid: called with too many arguments"));
-
 	if (get_argument(0, AWK_NUMBER, &pid)) {
 		options = WNOHANG|WUNTRACED;
 		ret = waitpid(pid.num_value, NULL, options);
 		if (ret < 0)
 			update_ERRNO_int(errno);
-	} else if (do_lint)
-		lintwarn(ext_id, _("wait: called with no arguments"));
+	}
 
 	/* Set the return value */
 	return make_number(ret, result);
@@ -139,9 +132,6 @@ do_wait(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 0)
-		lintwarn(ext_id, _("wait: called with too many arguments"));
-
 	ret = wait(NULL);
 	if (ret < 0)
 		update_ERRNO_int(errno);
@@ -151,9 +141,9 @@ do_wait(int nargs, awk_value_t *result)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "fork", do_fork, 0 },
-	{ "waitpid", do_waitpid, 1 },
-	{ "wait", do_wait, 0 },
+	{ "fork", do_fork, 0, 0 },
+	{ "waitpid", do_waitpid, 1, 1 },
+	{ "wait", do_wait, 0, 0 },
 };
 
 /* define the dl_load function using the boilerplate macro */
diff --git a/extension/inplace.c b/extension/inplace.c
index 26c37922..19ee5605 100644
--- a/extension/inplace.c
+++ b/extension/inplace.c
@@ -262,8 +262,8 @@ do_inplace_end(int nargs, awk_value_t *result)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "inplace_begin", do_inplace_begin, 2 },
-	{ "inplace_end", do_inplace_end, 2 },
+	{ "inplace_begin", do_inplace_begin, 2, 2 },
+	{ "inplace_end", do_inplace_end, 2, 2 },
 };
 
 static awk_bool_t init_inplace(void)
diff --git a/extension/ordchr.c b/extension/ordchr.c
index 4f9cd616..3722ced8 100644
--- a/extension/ordchr.c
+++ b/extension/ordchr.c
@@ -65,17 +65,10 @@ do_ord(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 1)
-		lintwarn(ext_id, _("ord: called with too many arguments"));
-
 	if (get_argument(0, AWK_STRING, & str)) {
 		ret = str.str_value.str[0];
-	} else if (do_lint) {
-		if (nargs == 0)
-			lintwarn(ext_id, _("ord: called with no arguments"));
-		else
-			lintwarn(ext_id, _("ord: called with inappropriate argument(s)"));
-	}
+	} else if (do_lint)
+		lintwarn(ext_id, _("ord: called with inappropriate argument(s)"));
 
 	/* Set the return value */
 	return make_number(ret, result);
@@ -95,29 +88,22 @@ do_chr(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 1)
-		lintwarn(ext_id, _("chr: called with too many arguments"));
-
 	if (get_argument(0, AWK_NUMBER, & num)) {
 		val = num.num_value;
 		ret = val;	/* convert to int */
 		ret &= 0xff;
 		str[0] = ret;
 		str[1] = '\0';
-	} else if (do_lint) {
-		if (nargs == 0)
-			lintwarn(ext_id, _("chr: called with no arguments"));
-		else
-			lintwarn(ext_id, _("chr: called with inappropriate argument(s)"));
-	}
+	} else if (do_lint)
+		lintwarn(ext_id, _("chr: called with inappropriate argument(s)"));
 
 	/* Set the return value */
 	return make_const_string(str, 1, result);
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "ord", do_ord, 1 },
-	{ "chr", do_chr, 1 },
+	{ "ord", do_ord, 1, 1 },
+	{ "chr", do_chr, 1, 1 },
 };
 
 /* define the dl_load function using the boilerplate macro */
diff --git a/extension/readfile.c b/extension/readfile.c
index fbe25748..cc9a4c14 100644
--- a/extension/readfile.c
+++ b/extension/readfile.c
@@ -109,9 +109,6 @@ do_readfile(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	make_null_string(result);	/* default return value */
 
-	if (do_lint && nargs > 1)
-		lintwarn(ext_id, _("readfile: called with too many arguments"));
-
 	unset_ERRNO();
 
 	if (get_argument(0, AWK_STRING, &filename)) {
@@ -134,7 +131,7 @@ do_readfile(int nargs, awk_value_t *result)
 		make_malloced_string(text, sbuf.st_size, result);
 		goto done;
 	} else if (do_lint)
-		lintwarn(ext_id, _("readfile: called with no arguments"));
+		lintwarn(ext_id, _("readfile: called with wrong kind of argument"));
 
 done:
 	/* Set the return value */
@@ -241,7 +238,7 @@ init_readfile()
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "readfile", do_readfile, 1 },
+	{ "readfile", do_readfile, 1, 1 },
 };
 
 /* define the dl_load function using the boilerplate macro */
diff --git a/extension/rwarray.c b/extension/rwarray.c
index 15e121af..8c3200ea 100644
--- a/extension/rwarray.c
+++ b/extension/rwarray.c
@@ -109,9 +109,6 @@ do_writea(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	make_number(0.0, result);
 
-	if (do_lint && nargs > 2)
-		lintwarn(ext_id, _("writea: called with too many arguments"));
-
 	if (nargs < 2)
 		goto out;
 
@@ -265,9 +262,6 @@ do_reada(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	make_number(0.0, result);
 
-	if (do_lint && nargs > 2)
-		lintwarn(ext_id, _("reada: called with too many arguments"));
-
 	if (nargs < 2)
 		goto out;
 
@@ -470,8 +464,8 @@ read_value(FILE *fp, awk_value_t *value)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "writea", do_writea, 2 },
-	{ "reada", do_reada, 2 },
+	{ "writea", do_writea, 2, 2 },
+	{ "reada", do_reada, 2, 2 },
 };
 
 
diff --git a/extension/rwarray0.c b/extension/rwarray0.c
index 00289cad..35e0a702 100644
--- a/extension/rwarray0.c
+++ b/extension/rwarray0.c
@@ -105,9 +105,6 @@ do_writea(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	make_number(0.0, result);
 
-	if (do_lint && nargs > 2)
-		lintwarn(ext_id, _("writea: called with too many arguments"));
-
 	if (nargs < 2)
 		goto out;
 
@@ -261,9 +258,6 @@ do_reada(int nargs, awk_value_t *result)
 	assert(result != NULL);
 	make_number(0.0, result);
 
-	if (do_lint && nargs > 2)
-		lintwarn(ext_id, _("reada: called with too many arguments"));
-
 	if (nargs < 2)
 		goto out;
 
@@ -465,8 +459,8 @@ read_value(int fd, awk_value_t *value)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "writea", do_writea, 2 },
-	{ "reada", do_reada, 2 },
+	{ "writea", do_writea, 2, 2 },
+	{ "reada", do_reada, 2, 2 },
 };
 
 
diff --git a/extension/testext.c b/extension/testext.c
index 9216d64a..227714e1 100644
--- a/extension/testext.c
+++ b/extension/testext.c
@@ -1024,20 +1024,20 @@ static void at_exit2(void *data, int exit_status)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "dump_array_and_delete", dump_array_and_delete, 2 },
-	{ "try_modify_environ", try_modify_environ, 0 },
-	{ "var_test", var_test, 1 },
-	{ "test_deferred", test_deferred, 0 },
-	{ "test_errno", test_errno, 0 },
-	{ "test_array_size", test_array_size, 1 },
-	{ "test_array_elem", test_array_elem, 2 },
-	{ "test_array_param", test_array_param, 1 },
-	{ "print_do_lint", print_do_lint, 0 },
-	{ "test_scalar", test_scalar, 1 },
-	{ "test_scalar_reserved", test_scalar_reserved, 0 },
-	{ "test_indirect_vars", test_indirect_vars, 0 },
-	{ "test_get_file", test_get_file, 2 },
-	{ "get_file", do_get_file, 4 },
+	{ "dump_array_and_delete", dump_array_and_delete, 2, 2 },
+	{ "try_modify_environ", try_modify_environ, 0, 0 },
+	{ "var_test", var_test, 1, 1 },
+	{ "test_deferred", test_deferred, 0, 0 },
+	{ "test_errno", test_errno, 0, 0 },
+	{ "test_array_size", test_array_size, 1, 1 },
+	{ "test_array_elem", test_array_elem, 2, 2 },
+	{ "test_array_param", test_array_param, 1, 1 },
+	{ "print_do_lint", print_do_lint, 0, 0 },
+	{ "test_scalar", test_scalar, 1, 1 },
+	{ "test_scalar_reserved", test_scalar_reserved, 0, 0 },
+	{ "test_indirect_vars", test_indirect_vars, 0, 0 },
+	{ "test_get_file", test_get_file, 2, 2 },
+	{ "get_file", do_get_file, 4, 4 },
 };
 
 /* init_testext --- additional initialization function */
diff --git a/extension/time.c b/extension/time.c
index e6b2b39f..67002752 100644
--- a/extension/time.c
+++ b/extension/time.c
@@ -109,9 +109,6 @@ do_gettimeofday(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 0)
-		lintwarn(ext_id, _("gettimeofday: ignoring arguments"));
-
 #if defined(HAVE_GETTIMEOFDAY)
 	{
 		struct timeval tv;
@@ -161,9 +158,6 @@ do_sleep(int nargs, awk_value_t *result)
 
 	assert(result != NULL);
 
-	if (do_lint && nargs > 1)
-		lintwarn(ext_id, _("sleep: called with too many arguments"));
-
 	if (! get_argument(0, AWK_NUMBER, &num)) {
 		update_ERRNO_string(_("sleep: missing required numeric argument"));
 		return make_number(-1, result);
@@ -212,8 +206,8 @@ do_sleep(int nargs, awk_value_t *result)
 }
 
 static awk_ext_func_t func_table[] = {
-	{ "gettimeofday", do_gettimeofday, 0 },
-	{ "sleep", do_sleep, 1 },
+	{ "gettimeofday", do_gettimeofday, 0, 0 },
+	{ "sleep", do_sleep, 1, 1 },
 };
 
 /* define the dl_load function using the boilerplate macro */
diff --git a/gawkapi.h b/gawkapi.h
index 1c884741..af362bd2 100644
--- a/gawkapi.h
+++ b/gawkapi.h
@@ -376,15 +376,22 @@ typedef struct awk_flat_array {
  * Each extension function may decide what to do if the number of
  * arguments isn't what it expected.  Following awk functions, it
  * is likely OK to ignore extra arguments.
-
- * Note that the 'max_expected_args' value should be used by the
- * extension function itself only to trigger a lint warning if more
- * arguments are passed to the function.
+ *
+ * 'min_required_args' indicates how many arguments MUST be passed.
+ * The API will throw a fatal error if not enough are passed.
+ *
+ * 'max_expected_args' is more benign; if more than that are passed,
+ * the API prints a lint message (IFF lint is enabled, of course).
+ *
+ * In any case, the extension function itself need not compare the
+ * actual number of arguments passed to those two values if it does
+ * not want to.
  */
 typedef struct awk_ext_func {
 	const char *name;
 	awk_value_t *(*function)(int num_actual_args, awk_value_t *result);
-	size_t max_expected_args;
+	unsigned short min_required_args;
+	unsigned short max_expected_args;
 } awk_ext_func_t;
 
 typedef void *awk_ext_id_t;	/* opaque type for extension id */
diff --git a/interpret.h b/interpret.h
index da8e0604..2cefc14c 100644
--- a/interpret.h
+++ b/interpret.h
@@ -956,8 +956,21 @@ arrayfor:
 		case Op_ext_builtin:
 		{
 			int arg_count = pc->expr_count;
+			int min_req = pc[1].min_required;
+			int max_expect = pc[1].max_expected;
 			awk_value_t result;
 
+			if (min_req == 0 && max_expect == 0 && arg_count > min_req)
+				fatal(_("%s: cannot be called with arguments"), pc[1].func_name);
+
+			if (min_req > 0 && arg_count < min_req)
+				fatal(_("%s: expects at least %d arguments, called with %d arguments"),
+						pc[1].func_name, min_req, arg_count);
+
+			if (do_lint && arg_count > max_expect)
+				lintwarn(_("%s: called with %d arguments, only expecting %d"),
+						pc[1].func_name, arg_count, max_expect);
+
 			PUSH_CODE(pc);
 			r = awk_value_to_node(pc->extfunc(arg_count, & result));
 			(void) POP_CODE();
@@ -1093,7 +1106,8 @@ match_re:
 					npc[0].expr_count = arg_count;		/* actual argument count */
 					npc[1] = pc[1];
 					npc[1].func_name = fname;	/* name of the builtin */
-					npc[1].expr_count = bc->expr_count;	/* defined max # of arguments */
+					npc[1].min_required = bc->min_required;
+					npc[1].max_expected = bc->max_expected;
 					ni = npc;
 					JUMPTO(ni);
 				} else