[lttng-dev] [RFC PATCH lttng-ust] Fix: convey enum value signedness into metadata

[Mathieu Desnoyers]

Currently, passing an enum range of:

  ctf_enum_range("blah", 0, UINT_MAX)

will print a range of 0 ... -1 in the generated CTF metadata, which does
not reflect signedness of the values.

Also, struct ustctl_enum_entry is missing a LTTNG_PACKED attribute,
which is against our protocol rules.

This change needs to be pushed in locked-step into lttng-tools and
lttng-ust, since it breaks the protocol between the two when UST uses
the new enumeration type (introduced in 2.8.0-rc1).

Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers at efficios.com>
---
 include/lttng/ust-ctl.h               | 11 ++++-
 liblttng-ust-comm/lttng-ust-comm.c    |  6 ++-
 liblttng-ust/lttng-ust-dynamic-type.c | 87 +++++++++++------------------------
 3 files changed, 40 insertions(+), 64 deletions(-)

diff --git a/include/lttng/ust-ctl.h b/include/lttng/ust-ctl.h
index 379ad41..06de95c 100644
--- a/include/lttng/ust-ctl.h
+++ b/include/lttng/ust-ctl.h
@@ -320,12 +320,19 @@ struct ustctl_float_type {
 	char padding[USTCTL_UST_FLOAT_TYPE_PADDING];
 } LTTNG_PACKED;
 
+#define USTCTL_UST_ENUM_VALUE_PADDING	15
+struct ustctl_enum_value {
+	uint64_t value;
+	uint8_t signedness;
+	char padding[USTCTL_UST_ENUM_VALUE_PADDING];
+} LTTNG_PACKED;
+
 #define USTCTL_UST_ENUM_ENTRY_PADDING	32
 struct ustctl_enum_entry {
-	uint64_t start, end;		/* start and end are inclusive */
+	struct ustctl_enum_value start, end; /* start and end are inclusive */
 	char string[LTTNG_UST_SYM_NAME_LEN];
 	char padding[USTCTL_UST_ENUM_ENTRY_PADDING];
-};
+} LTTNG_PACKED;
 
 #define USTCTL_UST_BASIC_TYPE_PADDING	296
 union _ustctl_basic_type {
diff --git a/liblttng-ust-comm/lttng-ust-comm.c b/liblttng-ust-comm/lttng-ust-comm.c
index 2c54a44..ecc2382 100644
--- a/liblttng-ust-comm/lttng-ust-comm.c
+++ b/liblttng-ust-comm/lttng-ust-comm.c
@@ -1088,8 +1088,10 @@ int serialize_entries(struct ustctl_enum_entry **_entries,
 		uentry = &entries[i];
 		lentry = &lttng_entries[i];
 
-		uentry->start = lentry->start;
-		uentry->end = lentry->end;
+		uentry->start.value = lentry->start.value;
+		uentry->start.signedness = lentry->start.signedness;
+		uentry->end.value = lentry->end.value;
+		uentry->end.signedness = lentry->end.signedness;
 		strncpy(uentry->string, lentry->string, LTTNG_UST_SYM_NAME_LEN);
 		uentry->string[LTTNG_UST_SYM_NAME_LEN - 1] = '\0';
 	}
diff --git a/liblttng-ust/lttng-ust-dynamic-type.c b/liblttng-ust/lttng-ust-dynamic-type.c
index c654f01..488cf81 100644
--- a/liblttng-ust/lttng-ust-dynamic-type.c
+++ b/liblttng-ust/lttng-ust-dynamic-type.c
@@ -29,67 +29,34 @@
 #include <helper.h>
 #include <lttng/ust-dynamic-type.h>
 
-static const struct lttng_enum_entry dt_enum[_NR_LTTNG_UST_DYNAMIC_TYPES] = {
-	[LTTNG_UST_DYNAMIC_TYPE_NONE] = {
-		.start = 0,
-		.end = 0,
-		.string = "_none",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_S8] = {
-		.start = 1,
-		.end = 1,
-		.string = "_int8",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_S16] = {
-		.start = 2,
-		.end = 2,
-		.string = "_int16",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_S32] = {
-		.start = 3,
-		.end = 3,
-		.string = "_int32",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_S64] = {
-		.start = 4,
-		.end = 4,
-		.string = "_int64",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_U8] = {
-		.start = 5,
-		.end = 5,
-		.string = "_uint8",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_U16] = {
-		.start = 6,
-		.end = 6,
-		.string = "_uint16",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_U32] = {
-		.start = 7,
-		.end = 7,
-		.string = "_uint32",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_U64] = {
-		.start = 8,
-		.end = 8,
-		.string = "_uint64",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_FLOAT] = {
-		.start = 9,
-		.end = 9,
-		.string = "_float",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_DOUBLE] = {
-		.start = 10,
-		.end = 10,
-		.string = "_double",
-	},
-	[LTTNG_UST_DYNAMIC_TYPE_STRING] = {
-		.start = 11,
-		.end = 11,
-		.string = "_string",
+#define ctf_enum_value(_string, _value)					\
+	{								\
+		.start = {						\
+			.signedness = lttng_is_signed_type(__typeof__(_value)), \
+			.value = lttng_is_signed_type(__typeof__(_value)) ? \
+				(long long) (_value) : (_value),	\
+		},							\
+		.end = {						\
+			.signedness = lttng_is_signed_type(__typeof__(_value)), \
+			.value = lttng_is_signed_type(__typeof__(_value)) ? \
+				(long long) (_value) : (_value),	\
+		},							\
+		.string = (_string),					\
 	},
+
+static const struct lttng_enum_entry dt_enum[_NR_LTTNG_UST_DYNAMIC_TYPES] = {
+	[LTTNG_UST_DYNAMIC_TYPE_NONE] = ctf_enum_value("_none", 0)
+	[LTTNG_UST_DYNAMIC_TYPE_S8] = ctf_enum_value("_int8", 1)
+	[LTTNG_UST_DYNAMIC_TYPE_S16] = ctf_enum_value("_int16", 2)
+	[LTTNG_UST_DYNAMIC_TYPE_S32] = ctf_enum_value("_int32", 3)
+	[LTTNG_UST_DYNAMIC_TYPE_S64] = ctf_enum_value("_int64", 4)
+	[LTTNG_UST_DYNAMIC_TYPE_U8] = ctf_enum_value("_uint8", 5)
+	[LTTNG_UST_DYNAMIC_TYPE_U16] = ctf_enum_value("_uint16", 6)
+	[LTTNG_UST_DYNAMIC_TYPE_U32] = ctf_enum_value("_uint32", 7)
+	[LTTNG_UST_DYNAMIC_TYPE_U64] = ctf_enum_value("_uint64", 8)
+	[LTTNG_UST_DYNAMIC_TYPE_FLOAT] = ctf_enum_value("_float", 9)
+	[LTTNG_UST_DYNAMIC_TYPE_DOUBLE] = ctf_enum_value("_double", 10)
+	[LTTNG_UST_DYNAMIC_TYPE_STRING] = ctf_enum_value("_string", 11)
 };
 
 static const struct lttng_enum_desc dt_enum_desc = {
-- 
2.1.4