Add command line options (and function) to get the release

Add the following function and command line options to get the current
release of bpfilter:
- bfcli --version
- bpfilter --version
- bf_version() in libbpfilter

src/bfcli/CMakeLists.txt

@@ -50,6 +50,7 @@ add_custom_target(bfcli_lexer
 
 add_executable(bfcli
     ${CMAKE_CURRENT_SOURCE_DIR}/main.c
+    ${CMAKE_BINARY_DIR}/include/version.h
     ${CMAKE_CURRENT_BINARY_DIR}/generated/include/bfcli/parser.h
     ${CMAKE_CURRENT_BINARY_DIR}/generated/bfcli/parser.c
     ${CMAKE_CURRENT_BINARY_DIR}/generated/include/bfcli/lexer.h
@@ -59,6 +60,7 @@ add_executable(bfcli
 target_include_directories(bfcli
     PRIVATE
         ${CMAKE_SOURCE_DIR}/src
+        ${CMAKE_BINARY_DIR}/include
         ${CMAKE_CURRENT_BINARY_DIR}/generated/include
         ${CMAKE_CURRENT_BINARY_DIR}/generated/include/bfcli
 )

src/bfcli/main.c

@@ -22,6 +22,7 @@
 #include "core/response.h"
 #include "core/set.h"
 #include "libbpfilter/bpfilter.h"
+#include "version.h"
 
 int bf_send(const struct bf_request *request, struct bf_response **response);
 
@@ -185,6 +186,15 @@ int main(int argc, char *argv[])
 
     bf_logger_setup();
 
+    // If any of the arguments is --version, print the version and return.
+    for (int i = 0; i < argc; ++i) {
+        if (bf_streq("--version", argv[i])) {
+            bf_info("bfcli version %s, libbpfilter version %s", BF_VERSION,
+                    bf_version());
+            exit(0);
+        }
+    }
+
     if (streq(obj_str, "ruleset") && streq(action_str, "set")) {
         r = _bf_do_ruleset_set(argc, argv);
     } else if (streq(obj_str, "ruleset") && streq(action_str, "flush")) {

src/bpfilter/CMakeLists.txt

@@ -12,6 +12,7 @@ configure_file(
 
 add_executable(bpfilter
     ${CMAKE_CURRENT_SOURCE_DIR}/main.c
+    ${CMAKE_BINARY_DIR}/include/version.h
     ${CMAKE_CURRENT_SOURCE_DIR}/cgen/cgen.h              ${CMAKE_CURRENT_SOURCE_DIR}/cgen/cgen.c
     ${CMAKE_CURRENT_SOURCE_DIR}/cgen/cgroup.h            ${CMAKE_CURRENT_SOURCE_DIR}/cgen/cgroup.c
     ${CMAKE_CURRENT_SOURCE_DIR}/cgen/dump.h              ${CMAKE_CURRENT_SOURCE_DIR}/cgen/dump.c
@@ -47,6 +48,7 @@ add_executable(bpfilter
 target_include_directories(bpfilter
     PUBLIC
         ${CMAKE_SOURCE_DIR}/src
+        ${CMAKE_BINARY_DIR}/include
 )
 
 target_link_libraries(bpfilter

src/bpfilter/main.c

@@ -273,14 +273,14 @@ static int _bf_init(int argc, char *argv[])
     if (sigaction(SIGTERM, &sighandler, NULL) < 0)
         return bf_err_r(errno, "can't override handler for SIGTERM");
 
-    r = _bf_ensure_runtime_dir();
-    if (r < 0)
-        return bf_err_r(r, "failed to ensure runtime directory exists");
-
     r = bf_opts_init(argc, argv);
     if (r < 0)
         return bf_err_r(r, "failed to parse command line arguments");
 
+    r = _bf_ensure_runtime_dir();
+    if (r < 0)
+        return bf_err_r(r, "failed to ensure runtime directory exists");
+
     // Either load context, or initialize it from scratch.
     if (!bf_opts_transient()) {
         r = _bf_load(ctx_path);

src/core/CMakeLists.txt

@@ -5,6 +5,7 @@ find_package(PkgConfig REQUIRED)
 pkg_check_modules(bpf REQUIRED IMPORTED_TARGET libbpf)
 
 set(core_srcs
+    ${CMAKE_BINARY_DIR}/include/version.h
     ${CMAKE_CURRENT_SOURCE_DIR}/bpf.h              ${CMAKE_CURRENT_SOURCE_DIR}/bpf.c
     ${CMAKE_CURRENT_SOURCE_DIR}/btf.h              ${CMAKE_CURRENT_SOURCE_DIR}/btf.c
     ${CMAKE_CURRENT_SOURCE_DIR}/chain.h            ${CMAKE_CURRENT_SOURCE_DIR}/chain.c
@@ -37,6 +38,7 @@ add_library(core
 target_include_directories(core
     PUBLIC
         ${CMAKE_SOURCE_DIR}/src
+        ${CMAKE_BINARY_DIR}/include
 )
 
 target_link_libraries(core

src/core/opts.c

@@ -16,12 +16,14 @@
 #include "core/front.h"
 #include "core/helper.h"
 #include "core/logger.h"
+#include "version.h"
 
 enum
 {
     BF_OPT_NO_IPTABLES_KEY,
     BF_OPT_NO_NFTABLES_KEY,
     BF_OPT_NO_CLI_KEY,
+    BF_OPT_VERSION,
 };
 
 static const char *_bf_verbose_strs[] = {
@@ -89,6 +91,7 @@ static struct argp_option options[] = {
     {"no-cli", BF_OPT_NO_CLI_KEY, 0, 0, "Disable CLI support", 0},
     {"verbose", 'v', "VERBOSE_FLAG", 0,
      "Verbose flags to enable. Can be used more than once.", 0},
+    {"version", BF_OPT_VERSION, 0, 0, "Print the version and return.", 0},
     {0},
 };
 
@@ -148,6 +151,9 @@ static error_t _bf_opts_parser(int key, char *arg, struct argp_state *state)
         bf_info("enabling verbose for '%s'", arg);
         args->verbose |= (1 << opt);
         break;
+    case BF_OPT_VERSION:
+        bf_info("bpfilter version %s", BF_VERSION);
+        exit(0);
     default:
         return ARGP_ERR_UNKNOWN;
     }

src/libbpfilter/CMakeLists.txt

@@ -7,6 +7,7 @@ set(libbpfilter_srcs
     ${CMAKE_CURRENT_SOURCE_DIR}/generic.h           ${CMAKE_CURRENT_SOURCE_DIR}/generic.c
                                                     ${CMAKE_CURRENT_SOURCE_DIR}/ipt.c
                                                     ${CMAKE_CURRENT_SOURCE_DIR}/nft.c
+    ${CMAKE_BINARY_DIR}/include/version.h           ${CMAKE_CURRENT_SOURCE_DIR}/version.c
 )
 
 configure_file(
@@ -29,6 +30,7 @@ set_target_properties(libbpfilter PROPERTIES OUTPUT_NAME bpfilter)
 target_include_directories(libbpfilter
     PRIVATE
         ${CMAKE_SOURCE_DIR}/src
+        ${CMAKE_BINARY_DIR}/include
 )
 
 target_link_libraries(libbpfilter

src/libbpfilter/bpfilter.h

@@ -14,6 +14,13 @@ struct ipt_replace;
 struct xt_counters_info;
 struct nlmsghdr;
 
+/**
+ * Return the version of the library.
+ *
+ * @return Version of the library, as a string.
+ */
+const char *bf_version(void);
+
 /**
  * Request the daemon to remove all the chains and rules.
  *

src/libbpfilter/version.c

@@ -0,0 +1,11 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Meta Platforms, Inc. and affiliates.
+ */
+
+#include "version.h"
+
+const char *bf_version(void)
+{
+    return BF_VERSION;
+}

src/version.h.in

@@ -0,0 +1,8 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright (c) 2023 Meta Platforms, Inc. and affiliates.
+ */
+
+#pragma once
+
+#define BF_VERSION "@PROJECT_VERSION@@PROJECT_VERSION_TWEAK@"

tests/unit/CMakeLists.txt

@@ -123,6 +123,7 @@ target_include_directories(unit_bin
     PRIVATE
         ${CMAKE_SOURCE_DIR}/src         # First look for headers in src/
         ${CMAKE_CURRENT_SOURCE_DIR}     # Then use overrides in tests/units
+        ${CMAKE_BINARY_DIR}/include
 )
 
 target_link_libraries(unit_bin