From e1a691b2b04b383f052d16931f5c34d6bc9d9e22 Mon Sep 17 00:00:00 2001
From: David Phillips <david@sighup.nz>
Date: Thu, 28 Dec 2017 13:51:51 +1300
Subject: Rough-work expr/op parser stubs in
---
common.h | 6 ++++++
parser.c | 37 ++++++++++++++++++++++++++++++++++++-
2 files changed, 42 insertions(+), 1 deletion(-)
create mode 100644 common.h
diff --git a/common.h b/common.h
new file mode 100644
index 0000000..e5c0ab4
--- /dev/null
+++ b/common.h
@@ -0,0 +1,6 @@
+#ifndef COMMON_H
+#define COMMON_H
+
+#define MIN(a, b) (((a) < (b)) ? (a) : (b))
+
+#endif
diff --git a/parser.c b/parser.c
index b2218b1..2f08f46 100644
--- a/parser.c
+++ b/parser.c
@@ -2,6 +2,7 @@
#include <stdio.h>
#include <string.h>
+#include "common.h"
#include "error.h"
#include "logic.h"
#include "wire.h"
@@ -52,6 +53,20 @@ static struct bop_lookup bop_handlers[] = {
{.str = "xor", .handler = logic_xor}
};
+int
+expect(const char *expect, char *actual) {
+ int min_len = 0;
+
+ min_len = MIN(strlen(expect), strlen(actual));
+
+ if (strncmp(expect, actual, min_len) != 0) {
+ emit_error("Expected '%s' at start of '%s'\n", expect, actual);
+ return 1;
+ }
+ return 0;
+}
+
+
int parse_uop(char *str, enum BINARY (*handler)(enum BINARY)) {
/**/
(void)str;
@@ -73,6 +88,7 @@ parse_op(char *str) {
int match = 0;
size_t i = 0;
+ strtok(str, " ");
match = 0;
for (i = 0; i < sizeof(bop_handlers)/sizeof(bop_handlers[0]); i++) {
if (strcmp(bop_handlers[i].str, str) == 0) {
@@ -99,8 +115,27 @@ parse_op(char *str) {
int
parse_expr(char *str) {
+ const char *expr_sep = ": ";
+ size_t ident_len = 0;
+ char *ident = NULL;
+ char *op = NULL;
+
printf("expression %s\n", str);
- return 0;
+
+ /* FIXME magic constant string */
+ ident_len = strspn(str, "abcdefghijklmnopqrstuvwxyz0123456789");
+
+ if (expect(expr_sep, str + ident_len)) {
+ return -1;
+ }
+
+ str[ident_len] = '\0';
+ ident = str;
+ op = str + ident_len + strlen(expr_sep);
+
+ /* FIXME do something with the identifier */
+
+ return parse_op(op);
}
int
--
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