1 files changed, 112 insertions, 0 deletions
diff --git a/tools/perf/util/expr.c b/tools/perf/util/expr.c
new file mode 100644
index 000000000000..fd192ddf93c1
--- /dev/null
+++ b/tools/perf/util/expr.c
@@ -0,0 +1,112 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <stdbool.h>
+#include <assert.h>
+#include "expr.h"
+#include "expr-bison.h"
+#define YY_EXTRA_TYPE int
+#include "expr-flex.h"
+
+#ifdef PARSER_DEBUG
+extern int expr_debug;
+#endif
+
+/* Caller must make sure id is allocated */
+void expr__add_id(struct parse_ctx *ctx, const char *name, double val)
+{
+	int idx;
+
+	assert(ctx->num_ids < MAX_PARSE_ID);
+	idx = ctx->num_ids++;
+	ctx->ids[idx].name = name;
+	ctx->ids[idx].val = val;
+}
+
+void expr__ctx_init(struct parse_ctx *ctx)
+{
+	ctx->num_ids = 0;
+}
+
+static int
+__expr__parse(double *val, struct parse_ctx *ctx, const char *expr,
+	      int start)
+{
+	YY_BUFFER_STATE buffer;
+	void *scanner;
+	int ret;
+
+	ret = expr_lex_init_extra(start, &scanner);
+	if (ret)
+		return ret;
+
+	buffer = expr__scan_string(expr, scanner);
+
+#ifdef PARSER_DEBUG
+	expr_debug = 1;
+#endif
+
+	ret = expr_parse(val, ctx, scanner);
+
+	expr__flush_buffer(buffer, scanner);
+	expr__delete_buffer(buffer, scanner);
+	expr_lex_destroy(scanner);
+	return ret;
+}
+
+int expr__parse(double *final_val, struct parse_ctx *ctx, const char *expr)
+{
+	return __expr__parse(final_val, ctx, expr, EXPR_PARSE) ? -1 : 0;
+}
+
+static bool
+already_seen(const char *val, const char *one, const char **other,
+	     int num_other)
+{
+	int i;
+
+	if (one && !strcasecmp(one, val))
+		return true;
+	for (i = 0; i < num_other; i++)
+		if (!strcasecmp(other[i], val))
+			return true;
+	return false;
+}
+
+int expr__find_other(const char *expr, const char *one, const char ***other,
+		     int *num_other)
+{
+	int err, i = 0, j = 0;
+	struct parse_ctx ctx;
+
+	expr__ctx_init(&ctx);
+	err = __expr__parse(NULL, &ctx, expr, EXPR_OTHER);
+	if (err)
+		return -1;
+
+	*other = malloc((ctx.num_ids + 1) * sizeof(char *));
+	if (!*other)
+		return -ENOMEM;
+
+	for (i = 0, j = 0; i < ctx.num_ids; i++) {
+		const char *str = ctx.ids[i].name;
+
+		if (already_seen(str, one, *other, j))
+			continue;
+
+		str = strdup(str);
+		if (!str)
+			goto out;
+		(*other)[j++] = str;
+	}
+	(*other)[j] = NULL;
+
+out:
+	if (i != ctx.num_ids) {
+		while (--j)
+			free((char *) (*other)[i]);
+		free(*other);
+		err = -1;
+	}
+
+	*num_other = j;
+	return err;
+}