Update README + path resolution changes (#4)

Author: ludviggunne

README.md

@@ -1,2 +1,22 @@
 # run-cppcheck
-cppcheck wrapper to simplify cppcheck integration
+
+A wrapper for cppcheck to simplify cppcheck integration. This program exists to provide a way
+to configure how to run cppcheck on a single file, that can be shared between editor plugins.
+The log file also provides additional information that plugins may be lacking.
+
+## Invocation
+
+```console
+run-cppcheck <file>
+```
+
+## Configuration options
+The configuration file is written in json, as **run-cppcheck-config.json**. It is searched for recursively in parent directories of the analyzed file.
+
+- **project_file**: a path to a project file accepted by the cppcheck option **--project=...**. If the path is relative,
+                    it's interpreted as relative to the configuration file.
+- **cppcheck**: cppcheck command.
+- **log_file**: Path to log file. The default log file location is `$XDG_STATE_HOME/run-cppcheck` or `$HOME/.local/state/run-cppcheck` on Linux,
+                and `%LOCALAPPDATA%\run-cppcheck` on Windows. The log file may provide more information than the editor plugin if analysis fails.
+- **enable_logging**: Default is `true`.
+- **args**: Extra arguments to pass to cppcheck. Example: `["--enable=style"]`.

config.cpp

@@ -138,14 +138,12 @@ std::string Config::parseArgs(int argc, char **argv)
 
     ++argv;
 
-    std::filesystem::path configPath = "";
-
     for (; *argv; ++argv) {
         const char *arg = *argv;
         const char *value;
 
         if ((value = startsWith(arg, "--config="))) {
-            configPath = value;
+            m_configPath = value;
             continue;
         }
 
@@ -166,16 +164,20 @@ std::string Config::parseArgs(int argc, char **argv)
         if (!error.empty())
             return error;
     }
-    if (configPath.empty())
-        configPath = findConfig(m_filename);
+    if (m_configPath.empty())
+        m_configPath = findConfig(m_filename);
 
-    if (configPath.empty())
+    if (m_configPath.empty())
         return "Failed to find config file";
 
-    const std::string err = load(configPath);
-    if (err.empty())
-        return "";
-    return "Failed to load '" + configPath.string() + "': " + err;
+    const std::string err = load(m_configPath);
+    if (!err.empty())
+        return "Failed to load '" + m_configPath.string() + "': " + err;
+
+    if (!m_projectFilePath.empty() && m_projectFilePath.is_relative())
+        m_projectFilePath = m_configPath.parent_path() / m_projectFilePath;
+
+    return "";
 }
 
 // Find config file by recursively searching parent directories of input file

config.h

@@ -10,6 +10,7 @@ class Config {
     Config()
         : m_projectFilePath("")
         , m_logFilePath("")
+        , m_configPath("")
         , m_loggingEnabled(true)
         , m_cppcheck("cppcheck")
         , m_filename("")
@@ -35,12 +36,18 @@ class Config {
         return m_logFilePath;
     }
 
+    const std::filesystem::path configPath() const
+    {
+        return m_configPath;
+    }
+
 private:
     static std::filesystem::path findConfig(const std::filesystem::path &input_path);
     static std::string getDefaultLogFilePath(std::filesystem::path &path);
 
     std::filesystem::path m_projectFilePath;
     std::filesystem::path m_logFilePath;
+    std::filesystem::path m_configPath;
     bool m_loggingEnabled;
     std::string m_cppcheck;
     std::filesystem::path m_filename;

main.cpp

@@ -76,7 +76,8 @@ int main(int argc, char** argv) {
 
     const std::string cmd = config.command();
 
-    logfile << "CMD: " << cmd << std::endl;
+    logfile << "config path: " << config.configPath() << std::endl;
+    logfile << "command: " << cmd << std::endl;
 
     std::string output;
     int res = executeCommand(cmd, output);