Add support for generating compile_commands.json (#39)

.clangd

@@ -0,0 +1,2 @@
+CompileFlags:
+  CompilationDatabase: build/

.vscode/tasks.json

@@ -95,7 +95,30 @@
             "osx": {
                 "command": "premake5.osx"
             },
-            "group": "build"
+            "group": "build",
+            "dependsOn": ["Generate compile_commands.json"]
+        },
+        {
+            "label": "Generate compile_commands.json",
+            "type": "process",
+            "command": "./premake5",
+            "options": {
+                "cwd": "${workspaceFolder}/build/"
+            },
+            "args": [
+                "ecc"
+            ],
+            "windows": {
+                "command": "./premake5.exe"
+            },
+            "linux": {
+                "command": "./premake5"
+            },
+            "osx": {
+                "command": "premake5.osx"
+            },
+            "group": "build",
+            "problemMatcher": []
         }
     ]
 }

build/ecc/LICENSE.md

@@ -0,0 +1,29 @@
+BSD 3-Clause License
+
+Copyright (c) 2022, Matvey Bystrin
+All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+1. Redistributions of source code must retain the above copyright notice, this
+   list of conditions and the following disclaimer.
+
+2. Redistributions in binary form must reproduce the above copyright notice,
+   this list of conditions and the following disclaimer in the documentation
+   and/or other materials provided with the distribution.
+
+3. Neither the name of the copyright holder nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

build/ecc/README.md

@@ -0,0 +1,49 @@
+# Export Compile Commands - ECC
+Module implementing support for [JSON Compilation Database Format
+Specification](https://clang.llvm.org/docs/JSONCompilationDatabase.html).
+
+This is an alternative to
+[tarruda's](https://github.com/tarruda/premake-export-compile-commands) module,
+which does one simple thing - generates one `compile_commands.json` file for
+your project.
+
+Tested with clangd-13.
+
+## Requirements
+Premake 5.0.0 or later.
+
+## How to use
+Download premake-ecc and place it near your premake5.lua script. Then require it
+from your premake script
+
+```lua
+require "ecc/ecc"
+```
+
+After you simply can call:
+
+```
+premake5 ecc
+```
+
+Moldule will generate **one** `compile_commands.json` file near your main
+premake script. During generation it will use the default config (the first one
+you have specified in script). If you want to select specific config just pass
+it's name with command line option:
+
+```
+premake5 --config=release ecc
+```
+
+Careful! `config` option case sensitive! If there is no config passed via
+command line, module will choose the default one. 
+
+Note: if you want to embed this module into your premake build follow
+the [manual](https://premake.github.io/docs/Embedding-Modules/)
+
+## Future plans
+- Add unit tests
+
+## Alternatives
+- [export-compile-commands](https://github.com/tarruda/premake-export-compile-commands)
+- [bear](https://github.com/rizsotto/Bear)

build/ecc/_manifest.lua

@@ -0,0 +1,4 @@
+return {
+	"_preload.lua",
+	"ecc.lua"
+}

build/ecc/_preload.lua

@@ -0,0 +1,35 @@
+
+	local p = premake
+
+	newoption {
+		trigger = "config",
+		value = "CFG",
+		description = "Select config for export compile_commands.json"
+	}
+
+	newaction {
+		trigger         = "ecc",
+		shortname       = "Export compile commands",
+		description     = "Export compile_commands.json for language server",
+		toolset         = "gcc",
+
+		valid_kinds     = { "ConsoleApp", "WindowedApp", "StaticLib", "SharedLib" },
+		valid_languages = { "C", "C++" },
+		valid_tools     = {
+			cc     = { "clang", "gcc" }
+		},
+
+		onStart = function()
+			p.indent("  ")
+		end,
+
+		execute = function()
+			local dir = {}
+			dir.location = _MAIN_SCRIPT_DIR
+			p.generate(dir, "compile_commands.json", p.modules.ecc.generateFile)
+		end
+	}
+
+	return function(cfg)
+		return (_ACTION == "ecc")
+	end

build/ecc/ecc.lua

@@ -0,0 +1,122 @@
+	
+	-- Include module if it is not embedded
+	if premake.modules.ecc == nil then
+		include ( "_preload.lua" )
+	end
+
+	local p = premake
+	local project = p.project
+
+	p.modules.ecc = {}
+	local m = p.modules.ecc
+
+	m._VERSION = "1.0.1-alpha"
+
+	function m.generateFile()
+		p.push("[")
+		for wks in p.global.eachWorkspace() do
+			for prj in p.workspace.eachproject(wks) do
+				m.onProject(prj)
+			end
+		end
+		p.pop("]")
+	end
+
+	function m.onProject(prj)
+		if project.isc(prj) or project.iscpp(prj) then
+			local cfg = m.getConfig(prj)
+			local args = m.getArguments(prj, cfg)
+			local files = table.shallowcopy(prj._.files)
+			for i,node in ipairs(files) do
+				local output = cfg.objdir .. "/" ..  node.objname .. ".o"
+				local obj = path.getrelative(prj.location, output)
+				p.push("{")
+				p.push("\"arguments\": [")
+				m.writeArgs(args, obj, node.relpath)
+				p.pop("],")
+				p.w("\"directory\": \"%s\",", prj.location)
+				p.w("\"file\": \"%s\",", node.abspath)
+				p.w("\"output\": \"%s\"", output)
+				p.pop("},")
+			end
+		end
+	end
+
+	function m.writeArgs(args, obj, src)
+		for _,arg in ipairs(args) do
+			-- Defines like the following will break JSON format, quotes need to be escaped
+			-- -DEXPORT_API=__attribute__((visibility("default")))
+			local escaped = arg:gsub("\"", "\\\"")
+			p.w("\"%s\",", escaped)
+		end
+		p.w("\"-c\",")
+		p.w("\"-o\",")
+		p.w("\"%s\",", obj)
+		p.w("\"%s\"", src)
+	end
+
+	function m.getConfig(prj)
+		local ocfg = _OPTIONS.config
+		local cfg = {}
+		if ocfg and prj.configs[ocfg] then
+			cfg = prj.configs[ocfg]
+		else
+			cfg = m.defaultconfig(prj)
+		end
+		return cfg
+	end
+
+	function m.getArguments(prj, cfg)
+		local toolset = m.getToolSet(cfg)
+		local args = {}
+		local tool = iif(project.iscpp(prj), "cxx", "cc")
+		local toolname = iif(cfg.prefix, toolset.gettoolname(cfg, tool), toolset.tools[tool])
+		args = table.join(args, toolname)
+		args = table.join(args, toolset.getcppflags(cfg)) -- Preprocessor
+		args = table.join(args, toolset.getdefines(cfg.defines))
+		args = table.join(args, toolset.getundefines(cfg.undefines))
+		args = table.join(args, toolset.getincludedirs(cfg, cfg.includedirs, cfg.sysincludedirs))
+		if project.iscpp(prj) then
+			args = table.join(args, toolset.getcxxflags(cfg))
+		else
+			args = table.join(args, toolset.getcflags(cfg))
+		end
+		args = table.join(args, cfg.buildoptions)
+		return args
+	end
+
+	-- Copied from gmake2 module
+	-- Return default toolset of given config or  system default toolset
+	function m.getToolSet(cfg)
+		local default = iif(cfg.system == p.MACOSX, "clang", "gcc")
+		local toolset = p.tools[_OPTIONS.cc or cfg.toolset or default]
+		if not toolset then
+			error("Invalid toolset '" .. cfg.toolset .. "'")
+		end
+		return toolset
+	end
+
+	-- Copied from gmake2 module
+	function m.defaultconfig(target)
+		-- find the right configuration iterator function for this object
+		local eachconfig = iif(target.project, project.eachconfig, p.workspace.eachconfig)
+		local defaultconfig = nil
+
+		-- find the right default configuration platform, grab first configuration that matches
+		if target.defaultplatform then
+			for cfg in eachconfig(target) do
+				if cfg.platform == target.defaultplatform then
+					defaultconfig = cfg
+					break
+				end
+			end
+		end
+
+		-- grab the first configuration and write the block
+		if not defaultconfig then
+			local iter = eachconfig(target)
+			defaultconfig = iter()
+		end
+
+		return defaultconfig
+	end

build/premake5.lua

@@ -1,3 +1,6 @@
+-- Export Compile Commands module for clangd support
+require "ecc/ecc"
+
 newoption
 {
     trigger = "graphics",