summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
authorPatrick McHardy <kaber@trash.net>2014-12-13 07:50:35 +0000
committerPatrick McHardy <kaber@trash.net>2014-12-16 18:20:54 +0100
commit51425ecaa06296c467fded2ad5bf1b23f8a90cdd (patch)
treeb4bd61c545c9ac9be7a57b051e5c597e7dbbbf41
parent0b915d6dc50e9e5aeb3e41db9d20dc96d9edee3f (diff)
datatype: add define for maximum number of bits and mask of datatype id
The id of concat datatypes is composed of the ids of the individual datatypes. Add a define for the number of bits for each datatype id and a mask. The number of bits is chosen as 6, allowing for 63 datatypes, or twice as much as we currently have. This allows for concatenations of 5 types using 32 bits. The value is statically chosen instead of basing it on the current numbers of datatypes since we don't want the maximum concatenation size to vary between versions, also new versions are supposed to be able to propery parse a ruleset generated by an older version. Signed-off-by: Patrick McHardy <kaber@trash.net>
-rw-r--r--include/datatype.h3
-rw-r--r--src/datatype.c3
-rw-r--r--src/evaluate.c2
3 files changed, 6 insertions, 2 deletions
diff --git a/include/datatype.h b/include/datatype.h
index 50b85c31..ca6ba9fe 100644
--- a/include/datatype.h
+++ b/include/datatype.h
@@ -82,6 +82,9 @@ enum datatypes {
};
#define TYPE_MAX (__TYPE_MAX - 1)
+#define TYPE_BITS 6
+#define TYPE_MASK ((1 << TYPE_BITS) - 1)
+
/**
* enum byteorder
*
diff --git a/src/datatype.c b/src/datatype.c
index 8583531f..91e5ed6d 100644
--- a/src/datatype.c
+++ b/src/datatype.c
@@ -51,6 +51,7 @@ static const struct datatype *datatypes[TYPE_MAX + 1] = {
void datatype_register(const struct datatype *dtype)
{
+ BUILD_BUG_ON(TYPE_MAX & ~TYPE_MASK);
datatypes[dtype->type] = dtype;
}
@@ -939,7 +940,7 @@ const struct datatype *concat_type_alloc(const struct expr *expr)
strncat(desc, i->dtype->desc, sizeof(desc) - strlen(desc) - 1);
strncat(name, i->dtype->name, sizeof(name) - strlen(name) - 1);
- type <<= 8;
+ type <<= TYPE_BITS;
type |= i->dtype->type;
size += i->dtype->size;
subtypes++;
diff --git a/src/evaluate.c b/src/evaluate.c
index 79edf021..9cb2376a 100644
--- a/src/evaluate.c
+++ b/src/evaluate.c
@@ -617,7 +617,7 @@ static int expr_evaluate_concat(struct eval_ctx *ctx, struct expr **expr)
"unexpected concat component, "
"expecting %s",
dtype->desc);
- tmp = datatype_lookup((type >> 8 * --off) & 0xff);
+ tmp = datatype_lookup((type >> TYPE_BITS * --off) & TYPE_MASK);
expr_set_context(&ctx->ectx, tmp, tmp->size);
if (list_member_evaluate(ctx, &i) < 0)