harec

commit 1e39643dc342926d80fedd5ce6bc6aae7e075060
parent 084a4e9d986baf52f29235dba2bebe6b041d012b
Author: Drew DeVault <sir@cmpwn.com>
Date:   Thu, 31 Dec 2020 15:55:07 -0500

gen, emit: escape string constants

Diffstat:
M
include/qbe.h
 | 
5
++++-
M
src/emit.c
 | 
30
+++++++++++++++++++++++++++++-
M
src/gen.c
 | 
2
+-

3 files changed, 34 insertions(+), 3 deletions(-)
diff --git a/include/qbe.h b/include/qbe.h
@@ -228,7 +228,10 @@ struct qbe_data_item {
 	union {
 		struct qbe_value value;
 		size_t zeroed;
-		char *str;
+		struct {
+			char *str;
+			size_t sz;
+		};
 	};
 	struct qbe_data_item *next;
 };
diff --git a/src/emit.c b/src/emit.c
@@ -1,4 +1,5 @@
 #include <assert.h>
+#include <ctype.h>
 #include <stdio.h>
 #include "emit.h"
 #include "qbe.h"
@@ -192,6 +193,33 @@ emit_func(struct qbe_def *def, FILE *out)
 }
 
 static void
+emit_data_string(const char *str, size_t sz, FILE *out)
+{
+	bool q = false;
+	for (size_t i = 0; i < sz; ++i) {
+		/* XXX: We could stand to emit less conservatively */
+		if (!isprint(str[i]) || str[i] == '"' || str[i] == '\\') {
+			if (q) {
+				q = false;
+				fprintf(out, "\", ");
+			}
+			fprintf(out, "b %d, ", str[i]);
+		} else {
+			if (!q) {
+				q = true;
+				fprintf(out, "b \"");
+			}
+			fprintf(out, "%c", str[i]);
+		}
+	}
+	if (q) {
+		fprintf(out, "\", b 0, ");
+	} else {
+		fprintf(out, "b 0, ");
+	}
+}
+
+static void
 emit_data(struct qbe_def *def, FILE *out)
 {
 	assert(def->kind == Q_DATA);
@@ -207,7 +235,7 @@ emit_data(struct qbe_def *def, FILE *out)
 		case QD_ZEROED:
 			assert(0); // TODO
 		case QD_STRING:
-			fprintf(out, " b \"%s\", b 0", item->str);
+			emit_data_string(item->str, item->sz, out);
 			break;
 		}
 
diff --git a/src/gen.c b/src/gen.c
@@ -686,8 +686,8 @@ gen_string(struct gen_context *ctx,
 	def->name = temp.name;
 	def->kind = Q_DATA;
 	def->data.items.type = QD_STRING;
-	// TODO: Escape special characters
 	def->data.items.str = strdup(expr->constant.string.value);
+	def->data.items.sz = expr->constant.string.len;
 	qbe_append_def(ctx->out, def);
 
 	struct qbe_value str = {0};