MINOR: samples: add xx-hash functions
This patch adds the support of xx-hash 32 and 64-bits functions.
diff --git a/doc/configuration.txt b/doc/configuration.txt
index c4efbce..2a5f7dc 100644
--- a/doc/configuration.txt
+++ b/doc/configuration.txt
@@ -12806,6 +12806,24 @@
This prefix is followed by a name. The separator is a '.'. The name may only
contain characters 'a-z', 'A-Z', '0-9', '.' and '_'.
+xxh32([<seed>])
+ Hashes a binary input sample into an unsigned 32-bit quantity using the 32-bit
+ variant of the XXHash hash function. This hash supports a seed which defaults
+ to zero but a different value maybe passed as the <seed> argument. This hash
+ is known to be very good and very fast so it can be used to hash URLs and/or
+ URL parameters for use as stick-table keys to collect statistics with a low
+ collision rate, though care must be taken as the algorithm is not considered
+ as cryptographically secure.
+
+xxh64([<seed>])
+ Hashes a binary input sample into a signed 64-bit quantity using the 64-bit
+ variant of the XXHash hash function. This hash supports a seed which defaults
+ to zero but a different value maybe passed as the <seed> argument. This hash
+ is known to be very good and very fast so it can be used to hash URLs and/or
+ URL parameters for use as stick-table keys to collect statistics with a low
+ collision rate, though care must be taken as the algorithm is not considered
+ as cryptographically secure.
+
7.3.2. Fetching samples from internal states
--------------------------------------------
diff --git a/src/sample.c b/src/sample.c
index 81349cd..3cbe762 100644
--- a/src/sample.c
+++ b/src/sample.c
@@ -33,6 +33,8 @@
#include <proto/stick_table.h>
#include <proto/vars.h>
+#include <import/xxhash.h>
+
/* sample type names */
const char *smp_to_type[SMP_TYPES] = {
[SMP_T_ANY] = "any",
@@ -1617,6 +1619,41 @@
return 1;
}
+/* hashes the binary input into a 32-bit unsigned int using xxh.
+ * The seed of the hash defaults to 0 but can be changd in argument 1.
+ */
+static int sample_conv_xxh32(const struct arg *arg_p, struct sample *smp, void *private)
+{
+ unsigned int seed;
+
+ if (arg_p && arg_p->data.sint)
+ seed = arg_p->data.sint;
+ else
+ seed = 0;
+ smp->data.u.sint = XXH32(smp->data.u.str.str, smp->data.u.str.len, seed);
+ smp->data.type = SMP_T_SINT;
+ return 1;
+}
+
+/* hashes the binary input into a 64-bit unsigned int using xxh.
+ * In fact, the function returns a 64 bit unsigned, but the sample
+ * storage of haproxy only proposes 64-bits signed, so the value is
+ * cast as signed. This cast doesn't impact the hash repartition.
+ * The seed of the hash defaults to 0 but can be changd in argument 1.
+ */
+static int sample_conv_xxh64(const struct arg *arg_p, struct sample *smp, void *private)
+{
+ unsigned long long int seed;
+
+ if (arg_p && arg_p->data.sint)
+ seed = (unsigned long long int)arg_p->data.sint;
+ else
+ seed = 0;
+ smp->data.u.sint = (long long int)XXH64(smp->data.u.str.str, smp->data.u.str.len, seed);
+ smp->data.type = SMP_T_SINT;
+ return 1;
+}
+
/* hashes the binary input into a 32-bit unsigned int */
static int sample_conv_crc32(const struct arg *arg_p, struct sample *smp, void *private)
{
@@ -2680,6 +2717,8 @@
{ "djb2", sample_conv_djb2, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_T_SINT },
{ "sdbm", sample_conv_sdbm, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_T_SINT },
{ "wt6", sample_conv_wt6, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_T_SINT },
+ { "xxh32", sample_conv_xxh32, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_T_SINT },
+ { "xxh64", sample_conv_xxh64, ARG1(0,SINT), NULL, SMP_T_BIN, SMP_T_SINT },
{ "json", sample_conv_json, ARG1(1,STR), sample_conv_json_check, SMP_T_STR, SMP_T_STR },
{ "bytes", sample_conv_bytes, ARG2(1,SINT,SINT), NULL, SMP_T_BIN, SMP_T_BIN },
{ "field", sample_conv_field, ARG2(2,SINT,STR), sample_conv_field_check, SMP_T_STR, SMP_T_STR },