From: Karel Zak <kzak@redhat.com>
Date: Thu, 14 Sep 2023 09:55:03 +0000 (+0200)
Subject: libsmartcols: (filter) add regular expression operators
X-Git-Tag: v2.40-rc1~151^2~62
X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=408ae150a6a170708e2f678c594f415dd83eb65e;p=thirdparty%2Futil-linux.git

libsmartcols: (filter) add regular expression operators

Signed-off-by: Karel Zak <kzak@redhat.com>
---

diff --git a/libsmartcols/src/filter-expr.c b/libsmartcols/src/filter-expr.c
index b92023d346..ddd6437038 100644
--- a/libsmartcols/src/filter-expr.c
+++ b/libsmartcols/src/filter-expr.c
@@ -40,7 +40,6 @@ struct filter_node *filter_new_expr(
 	case F_EXPR_NEG:
 		n->right = right;
 		break;
-
 	}
 	return (struct filter_node *) n;
 }
@@ -202,7 +201,7 @@ int filter_eval_expr(struct libscols_filter *fltr, struct libscols_line *ln,
 	if (!rc)
 		rc = cast_node(fltr, ln, type, n->right, &r);
 	if (!rc)
-		rc = filter_compare_params(fltr, ln, oper, l, r, status);
+		rc = filter_compare_params(fltr, oper, l, r, status);
 
 	filter_unref_node((struct filter_node *) l);
 	filter_unref_node((struct filter_node *) r);
diff --git a/libsmartcols/src/filter-param.c b/libsmartcols/src/filter-param.c
index aeb286f4fb..295695e0a6 100644
--- a/libsmartcols/src/filter-param.c
+++ b/libsmartcols/src/filter-param.c
@@ -2,6 +2,7 @@
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#include <regex.h>
 
 #include "smartcolsP.h"
 
@@ -20,6 +21,7 @@ struct filter_param {
 	struct list_head pr_params;
 	struct libscols_column *col;
 	char *holder_name;
+	regex_t *re;
 
 	unsigned int has_value :1;
 };
@@ -107,6 +109,32 @@ struct filter_node *filter_new_param(
 	return (struct filter_node *) n;
 }
 
+int filter_compile_param(struct libscols_filter *fltr, struct filter_param *n)
+{
+	int rc;
+
+	if (n->re)
+		return 0;
+	if (!n->val.str)
+		return -EINVAL;
+
+	n->re = calloc(1, sizeof(regex_t));
+	if (!n->re)
+		return -ENOMEM;
+
+	rc = regcomp(n->re, n->val.str, REG_NOSUB | REG_EXTENDED);
+	if (rc) {
+		size_t size = regerror(rc, n->re, NULL, 0);
+
+		fltr->errmsg = malloc(size + 1);
+		if (!fltr->errmsg)
+			return -ENOMEM;
+		regerror(rc, n->re, fltr->errmsg, size);
+		return -EINVAL;
+	}
+	return 0;
+}
+
 static struct filter_param *copy_param(struct filter_param *n)
 {
 	return (struct filter_param *) filter_new_param(NULL,
@@ -120,8 +148,12 @@ static void param_reset_data(struct filter_param *n)
 
 	memset(&n->val, 0, sizeof(n->val));
 	n->has_value = 0;
-}
 
+	if (n->re) {
+		regfree(n->re);
+		free(n->re);
+	}
+}
 
 void filter_free_param(struct filter_param *n)
 {
@@ -312,6 +344,16 @@ static int string_opers(enum filter_etype oper, struct filter_param *l,
 	case F_EXPR_GT:
 		*status = xstrcmp(l->val.str, r->val.str) > 0;
 		break;
+	case F_EXPR_REG:
+		if (!r->re)
+			return -EINVAL;
+		*status = regexec(r->re, l->val.str ? : "", 0, NULL, 0) == 0;
+		break;
+	case F_EXPR_NREG:
+		if (!r->re)
+			return -EINVAL;
+		*status = regexec(r->re, l->val.str ? : "", 0, NULL, 0) != 0;
+		break;
 	default:
 		return -EINVAL;
 	}
@@ -405,7 +447,6 @@ static int bool_opers(enum filter_etype oper, struct filter_param *l,
 /* call filter_cast_param() to be sure that param data are ready (fetched from
  * holder, etc.) */
 int filter_compare_params(struct libscols_filter *fltr __attribute__((__unused__)),
-			  struct libscols_line *ln __attribute__((__unused__)),
 			  enum filter_etype oper,
 			  struct filter_param *l,
 			  struct filter_param *r,
diff --git a/libsmartcols/src/filter-parser.y b/libsmartcols/src/filter-parser.y
index cf03b4f2d9..c62aa15159 100644
--- a/libsmartcols/src/filter-parser.y
+++ b/libsmartcols/src/filter-parser.y
@@ -70,8 +70,18 @@ expr:
 	| expr T_LT expr	{ $$ = filter_new_expr(fltr, F_EXPR_LT, $1, $3); }
 	| expr T_GE expr	{ $$ = filter_new_expr(fltr, F_EXPR_GE, $1, $3); }
 	| expr T_GT expr	{ $$ = filter_new_expr(fltr, F_EXPR_GT, $1, $3); }
-	| expr T_REG expr	{ $$ = filter_new_expr(fltr, F_EXPR_REG, $1, $3); }
-	| expr T_NREG expr	{ $$ = filter_new_expr(fltr, F_EXPR_NREG, $1, $3); }
+
+	| expr T_REG expr	{
+		if (filter_compile_param(fltr, (struct filter_param *) $3) != 0)
+			YYERROR;
+		$$ = filter_new_expr(fltr, F_EXPR_REG, $1, $3);
+	}
+
+	| expr T_NREG expr	{
+		if (filter_compile_param(fltr, (struct filter_param *) $3) != 0)
+			YYERROR;
+		$$ = filter_new_expr(fltr, F_EXPR_NREG, $1, $3);
+	}
 ;
 
 param:
@@ -97,7 +107,9 @@ void yyerror (yyscan_t *locp __attribute__((__unused__)),
 	      struct libscols_filter *fltr,
 	      char const *msg)
 {
-	if (msg) {
+	if (msg && fltr) {
+		if (fltr->errmsg)
+			free(fltr->errmsg);
 		fltr->errmsg = strdup(msg);
 		if (!fltr->errmsg)
 			return;
diff --git a/libsmartcols/src/smartcolsP.h b/libsmartcols/src/smartcolsP.h
index 4ad86a858b..f892855c7c 100644
--- a/libsmartcols/src/smartcolsP.h
+++ b/libsmartcols/src/smartcolsP.h
@@ -548,6 +548,7 @@ int filter_eval_node(struct libscols_filter *fltr, struct libscols_line *ln,
 			struct filter_node *n, int *status);
 
 /* param */
+int filter_compile_param(struct libscols_filter *fltr, struct filter_param *n);
 void filter_dump_param(struct ul_jsonwrt *json, struct filter_param *n);
 int filter_eval_param(struct libscols_filter *fltr, struct libscols_line *ln,
 			struct filter_param *n, int *status);
@@ -559,7 +560,6 @@ int filter_next_param(struct libscols_filter *fltr,
                         struct libscols_iter *itr, struct filter_param **prm);
 
 int filter_compare_params(struct libscols_filter *fltr,
-                          struct libscols_line *ln,
                           enum filter_etype oper,
                           struct filter_param *l,
                           struct filter_param *r,