pkg/declextract: move const handling logic from the clang tool

Export raw info about consts from the clang tool, and let the Go part handle it.
The less logic is in the clang tool, the better. Also this will allow to remove
unused includes when we know which consts we ended up using.
The more includes we include, the higher the chances we include something
that's broken.

4 files changed, 108 insertions, 16 deletions

diff --git a/tools/syz-declextract/testdata/file_operations.c.json b/tools/syz-declextract/testdata/file_operations.c.json
index 94ad7bef5..df1c9a20f 100644
--- a/tools/syz-declextract/testdata/file_operations.c.json
+++ b/tools/syz-declextract/testdata/file_operations.c.json
@@ -47,8 +47,32 @@
 			"is_static": true
 		}
 	],
-	"includes": [
-		"include/uapi/file_operations.h"
+	"consts": [
+		{
+			"name": "FOO_IOCTL1",
+			"filename": "include/uapi/file_operations.h",
+			"value": 25345
+		},
+		{
+			"name": "FOO_IOCTL2",
+			"filename": "include/uapi/file_operations.h",
+			"value": 2147771138
+		},
+		{
+			"name": "FOO_IOCTL3",
+			"filename": "include/uapi/file_operations.h",
+			"value": 2148033283
+		},
+		{
+			"name": "FOO_IOCTL4",
+			"filename": "include/uapi/file_operations.h",
+			"value": 1074291460
+		},
+		{
+			"name": "FOO_IOCTL5",
+			"filename": "include/uapi/file_operations.h",
+			"value": 3221775109
+		}
 	],
 	"structs": [
 		{
diff --git a/tools/syz-declextract/testdata/io_uring.c.json b/tools/syz-declextract/testdata/io_uring.c.json
index 3f0a74a95..da91ce1b6 100644
--- a/tools/syz-declextract/testdata/io_uring.c.json
+++ b/tools/syz-declextract/testdata/io_uring.c.json
@@ -29,8 +29,27 @@
 			"file": "io_uring.c"
 		}
 	],
-	"includes": [
-		"include/uapi/io_uring.h"
+	"consts": [
+		{
+			"name": "IORING_OP_NOP",
+			"filename": "include/uapi/io_uring.h",
+			"value": 0
+		},
+		{
+			"name": "IORING_OP_NOT_SUPPORTED",
+			"filename": "include/uapi/io_uring.h",
+			"value": 3
+		},
+		{
+			"name": "IORING_OP_READV",
+			"filename": "include/uapi/io_uring.h",
+			"value": 1
+		},
+		{
+			"name": "IORING_OP_WRITEV",
+			"filename": "include/uapi/io_uring.h",
+			"value": 2
+		}
 	],
 	"iouring_ops": [
 		{
diff --git a/tools/syz-declextract/testdata/netlink.c.json b/tools/syz-declextract/testdata/netlink.c.json
index 4233eab7d..e1c2754b1 100644
--- a/tools/syz-declextract/testdata/netlink.c.json
+++ b/tools/syz-declextract/testdata/netlink.c.json
@@ -37,25 +37,71 @@
 			"is_static": true
 		}
 	],
-	"includes": [
-		"include/uapi/netlink_family.h"
-	],
-	"defines": [
+	"consts": [
 		{
 			"name": "NETLINK_BAR_CMD_FOO",
-			"value": "0"
+			"filename": "netlink.c",
+			"value": 0
+		},
+		{
+			"name": "NETLINK_FOO_ATTR1",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 0
+		},
+		{
+			"name": "NETLINK_FOO_ATTR2",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 1
+		},
+		{
+			"name": "NETLINK_FOO_ATTR3",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 4
+		},
+		{
+			"name": "NETLINK_FOO_ATTR4",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 5
+		},
+		{
+			"name": "NETLINK_FOO_ATTR5",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 6
+		},
+		{
+			"name": "NETLINK_FOO_ATTR6",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 7
+		},
+		{
+			"name": "NETLINK_FOO_ATTR7",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 8
+		},
+		{
+			"name": "NETLINK_FOO_CMD_BAR",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 1
+		},
+		{
+			"name": "NETLINK_FOO_CMD_FOO",
+			"filename": "include/uapi/netlink_family.h",
+			"value": 0
 		},
 		{
 			"name": "NETLINK_FOO_NESTED_ATTR1",
-			"value": "0"
+			"filename": "netlink.c",
+			"value": 0
 		},
 		{
 			"name": "NETLINK_FOO_NESTED_ATTR2",
-			"value": "1"
+			"filename": "netlink.c",
+			"value": 1
 		},
 		{
 			"name": "NETLINK_NOPOLICY_CMD",
-			"value": "0"
+			"filename": "netlink.c",
+			"value": 0
 		}
 	],
 	"structs": [
diff --git a/tools/syz-declextract/testdata/types.c.json b/tools/syz-declextract/testdata/types.c.json
index a5a7088db..82d45e3fe 100644
--- a/tools/syz-declextract/testdata/types.c.json
+++ b/tools/syz-declextract/testdata/types.c.json
@@ -111,18 +111,21 @@
 			]
 		}
 	],
-	"defines": [
+	"consts": [
 		{
 			"name": "a",
-			"value": "0"
+			"filename": "types.c",
+			"value": 0
 		},
 		{
 			"name": "b",
-			"value": "1"
+			"filename": "types.c",
+			"value": 1
 		},
 		{
 			"name": "c",
-			"value": "2"
+			"filename": "types.c",
+			"value": 2
 		}
 	],
 	"enums": [