From: Nick Bowler <nbowler@draconx.ca>
Date: Thu, 20 Jul 2023 02:22:10 +0000 (-0400)
Subject: libcdecl: Simplify Bison error message reporting.
X-Git-Tag: v1.3~104
X-Git-Url: https://git.draconx.ca/gitweb/cdecl99.git/commitdiff_plain/41ff7ec97691736525bb3da095afd5ca9a8ef003

libcdecl: Simplify Bison error message reporting.

Bison emits a bunch of code to pretty print token names for error
messages, doing things like removing quotes and backslashes.

But this is all totally pointless: all of the relevant strings are
already correctly formatted (in part because fix-yytname.awk does
some of this at compile time), and the process will not alter them.
They simply need to be copied as-is.

Fortunately, Bison provides a simple mechanism to replace this with
our own function, and wouldn't you know it we already have a suitable
copying function in the library, so let's use that.
---

diff --git a/src/cdecl-internal.h b/src/cdecl-internal.h
index 4c5ed0b..a5f3272 100644
--- a/src/cdecl-internal.h
+++ b/src/cdecl-internal.h
@@ -80,6 +80,7 @@ struct output_state {
 
 size_t cdecl__advance(struct output_state *dst, size_t amount);
 size_t cdecl__emit(struct output_state *dst, const char *src);
+size_t cdecl__strlcpy(char *dst, const char *src, size_t len);
 
 const char *cdecl__emit_specs(struct output_state *dst,
                               struct cdecl_declspec *s,
diff --git a/src/output.c b/src/output.c
index 1075221..7206eb9 100644
--- a/src/output.c
+++ b/src/output.c
@@ -38,7 +38,7 @@ size_t cdecl__advance(struct output_state *dst, size_t amount)
 	return amount;
 }
 
-static size_t cdecl__strlcpy(char *dst, const char *src, size_t dstlen)
+size_t cdecl__strlcpy(char *dst, const char *src, size_t dstlen)
 {
 	if (dst)
 		snprintf(dst, dstlen, "%s", src);
diff --git a/src/parse.y b/src/parse.y
index a993ea6..f507d5b 100644
--- a/src/parse.y
+++ b/src/parse.y
@@ -53,6 +53,13 @@
 	ALLOC(ptr, sizeof (type)); \
 	*(ptr) = (type) { __VA_ARGS__ }; \
 } while (0)
+
+/*
+ * With the postprocessing performed by fix-yytname.awk, all the symbol
+ * name strings can be used directly in error messages and there is no
+ * need for any string processing.
+ */
+#define yytnamerr(a, b) cdecl__strlcpy(a, b, (a) ? INT_MAX : 0)
 %}
 
 %code requires {