From 54bd5a4a3832a2f4c85cc34799022f61d0ddcf86 Mon Sep 17 00:00:00 2001
From: "Sven M. Hallberg" <pesco@khjk.org>
Date: Thu, 10 Jan 2013 23:44:28 +0100
Subject: [PATCH] add semantic actions for base64_3, base64_2, base64_1
---
examples/base64_sem1.c | 84 ++++++++++++++++++++++++++++++++++++++++--
1 file changed, 80 insertions(+), 4 deletions(-)
diff --git a/examples/base64_sem1.c b/examples/base64_sem1.c
index 83efc644..7839435a 100644
--- a/examples/base64_sem1.c
+++ b/examples/base64_sem1.c
@@ -1,4 +1,5 @@
#include "../src/hammer.h"
+#include "../src/internal.h" // for h_carray functions (XXX ?!)
#include <assert.h>
@@ -77,6 +78,81 @@ const HParsedToken *act_bsfdig(const HParseResult *p)
#define act_document act_index0
+// helper
+void carray_append_uint(HCountedArray *array, uint8_t value)
+{
+ HParsedToken *item = h_arena_malloc(array->arena, sizeof(HParsedToken));
+ item->token_type = TT_UINT;
+ item->uint = value;
+ h_carray_append(array, item);
+}
+
+const HParsedToken *act_base64_3(const HParseResult *p)
+{
+ assert(p->ast->token_type == TT_SEQUENCE);
+
+ HParsedToken *res = h_arena_malloc(p->arena, sizeof(HParsedToken));
+ res->token_type = TT_SEQUENCE;
+ res->seq = h_carray_new_sized(p->arena, 4);
+
+ HParsedToken **digits = p->ast->seq->elements;
+ uint32_t x = digits[0]->uint;
+ x <<= 6; x |= digits[1]->uint;
+ x <<= 6; x |= digits[2]->uint;
+ x <<= 6; x |= digits[3]->uint;
+
+ carray_append_uint(res->seq, (x >> 16) & 0xFF);
+ carray_append_uint(res->seq, (x >> 8) & 0xFF);
+ carray_append_uint(res->seq, x & 0xFF);
+
+ return res;
+}
+
+const HParsedToken *act_base64_2(const HParseResult *p)
+{
+ assert(p->ast->token_type == TT_SEQUENCE);
+
+ HParsedToken *res = h_arena_malloc(p->arena, sizeof(HParsedToken));
+ res->token_type = TT_SEQUENCE;
+ res->seq = h_carray_new_sized(p->arena, 4);
+
+ HParsedToken **digits = p->ast->seq->elements;
+ uint32_t x = digits[0]->uint;
+ x <<= 6; x |= digits[1]->uint;
+ x <<= 6; x |= digits[2]->uint;
+
+ carray_append_uint(res->seq, (x >> 10) & 0xFF);
+ carray_append_uint(res->seq, (x >> 2) & 0xFF);
+
+ return res;
+}
+
+const HParsedToken *act_base64_1(const HParseResult *p)
+{
+ assert(p->ast->token_type == TT_SEQUENCE);
+
+ HParsedToken *res = h_arena_malloc(p->arena, sizeof(HParsedToken));
+ res->token_type = TT_SEQUENCE;
+ res->seq = h_carray_new_sized(p->arena, 4);
+
+ HParsedToken **digits = p->ast->seq->elements;
+ uint32_t x = digits[0]->uint;
+ x <<= 6; x |= digits[1]->uint;
+
+ carray_append_uint(res->seq, (x >> 4) & 0xFF);
+
+ return res;
+}
+
+#if 0
+const HParsedToken *act_base64(const HParseResult *p)
+{
+ // XXX
+ // concatenate base64_3 blocks
+ // append trailing base64_2 or _1 block
+}
+#endif
+
///
// Set up the parser with the grammar to be recognized.
@@ -97,10 +173,10 @@ const HParser *init_parser(void)
H_ARULE(bsfdig, h_choice(alpha, digit, plus, slash, NULL));
H_ARULE(bsfdig_4bit, h_in((uint8_t *)"AEIMQUYcgkosw048", 16));
H_ARULE(bsfdig_2bit, h_in((uint8_t *)"AQgw", 4));
- H_RULE (base64_3, h_repeat_n(bsfdig, 4));
- H_RULE (base64_2, h_sequence(bsfdig, bsfdig, bsfdig_4bit, equals, NULL));
- H_RULE (base64_1, h_sequence(bsfdig, bsfdig_2bit, equals, equals, NULL));
- H_RULE (base64, h_sequence(h_many(base64_3),
+ H_ARULE(base64_3, h_repeat_n(bsfdig, 4));
+ H_ARULE(base64_2, h_sequence(bsfdig, bsfdig, bsfdig_4bit, equals, NULL));
+ H_ARULE(base64_1, h_sequence(bsfdig, bsfdig_2bit, equals, equals, NULL));
+ H_RULE(base64, h_sequence(h_many(base64_3),
h_optional(h_choice(base64_2,
base64_1, NULL)),
NULL));
--
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