0.2.0: added config + customization options

CMakeLists.txt

@@ -1,12 +1,30 @@
 cmake_minimum_required(VERSION 3.24)
 project(cppbtbl)
 
+set(SOURCE_DIR ${PROJECT_SOURCE_DIR}/src)
+
+set(CMAKE_COLOR_DIAGNOSTICS ON)
+
 find_package(sdbus-c++ REQUIRED)
 
-add_executable(cppbtbl cppbtbl.cpp)
+include_directories(${SOURCE_DIR})
+
+file(GLOB COMPILE_FILES ${SOURCE_DIR}/*.cpp)
+add_executable(${PROJECT_NAME} ${COMPILE_FILES})
+
 target_link_libraries(cppbtbl PRIVATE SDBusCpp::sdbus-c++)
 
+set_target_properties(${PROJECT_NAME}
+  PROPERTIES
+    LINKER_LANGUAGE CXX
+    CXX_STANDARD 20
+    CXX_STANDARD_REQUIRED YES
+    CXX_EXTENSIONS OFF
+)
+
+add_compile_options(-Wall -Wextra -Wshadow -Wpedantic -Wno-c++98-compat -Wfloat-conversion -Wno-unused-parameter -Wimplicit-fallthrough -Wconversion)
+
 install(
-    TARGETS cppbtbl
+    TARGETS ${PROJECT_NAME}
     DESTINATION ${CMAKE_INSTALL_PREFIX}/bin
 )

README.md

@@ -33,6 +33,30 @@ cppbtbl depends on sdbus-c++ which itself depends on libsystemd. Regardless of t
 
 Note that if you are using systemd, you won't have any issues using cppbtbl.
 
+## Configuration
+
+`cppbtbl` supports a variety of flags, which can be seen by doing `cppbtbl --help`.
+
+Each of these flags (in its long form) can be written inside a configuration file (with the format `name=value`) that is found inside either
+`$XDG_CONFIG_HOME/cppbtbl/config` (if defined) or `$HOME/.config/cppbtbl/config`.
+
+An example of this config file can be as follows:
+
+```
+format=custom
+output={icon} ({percentage}%)
+icons=1,2,3,4,5
+```
+
+You can also specify the `dont-follow` option here (if needed) by just typing it with no following characters.
+
+```
+format=custom
+output={icon} ({percentage}%)
+icons=1,2,3,4,5
+dont-follow
+```
+
 ## Waybar
 
 ```json
@@ -49,49 +73,34 @@ Note that if you are using systemd, you won't have any issues using cppbtbl.
 
 Change format and icons accordingly, and the module should work!
 
-## Other status bars
+## Polybar
 
-Two extra formats are offered to make cppbtbl usable in this case too. Those formats are `icononly` and `icon+devicename`. Please note that the default icons provided are part of the FontAwesome font, and (as of right now) the only way of changing them is by editing the source code.
+```
+[module/bt-battery]
+type = custom/script
 
-A better way to handle this, would be to make a script that reads `cppbtbl`'s output and re-writes it in whatever way is best for you. For example:
+exec = cppbtbl
 
-```bash
-#!/usr/bin/bash
-DEVICES=()
-PERCENTAGES=()
-timeout=
-while true; do
-    eval "read $timeout line"
-    if [ "$?" -ne "0" ]; then
-        [ -z "$timeout" ] && break
-        timeout=
-        # timeout, flush devices info
-        ...
-        continue
-    fi
-    if [ -z "$line" ]; then
-        timeout=
-        # clear ARRAYs, all devices have been disconnected
-        DEVICES=(); PERCENTAGES=()
-        echo ''
-        continue
-    fi
-
-    IFS=":"; read -a split <<< "${line//: /:}"; unset IFS
-    DEVICES[${#DEVICES}]="${split[0]}"
-    PERCENTAGES[${#PERCENTAGES}]="${split[1]}"
-    # time out read comamnd after 1 second (we supposed that if no other data is available within one second, we need to flush)
-    timeout="-t 1"
-done < <(cppbtbl -f raw)
+; This is necessary, because cppbtbl will continue running
+; so let's make sure polybar knows about it
+tail = true
 ```
 
-Please note that this is just an example, and it could likely be executed better.
+Now, you need to define your custom options, see [#configuration](#configuration).
+Please **make sure** to use `--format=custom`.
 
+## Other status bars
 
+In other status bars, just like we saw in Polybar, you can use `--format custom` and defining your own `--output`-format and your `--icons`-set
 
-Or a better way would be to just modify the source code to your likings.
+For example `cppbtbl --format custom --output "{icon} ({percentage}%)" --icons 'icon1,icon2,icon3'`.
 
+Keep in mind that by default the `cppbtbl` process will always be running and listening for connection/disconnection events, therefore your bar must be
+able to handle that. In case you want to use a "polling" approach, you can use the `--dont-follow` option, which will close the program once it
+returned the desired output.
 
+Please note that the "polling" approach won't be closely as efficient as the "listening" one, because too high of an interval will cause massive CPU usage,
+too low and you'll get a delay between your device being connected and it being shown in your bar.
 
 
 ### A thank-you goes to [@Justasic](https://github.com/Justasic) for helping me a lot in making this.

src/config.cpp

@@ -0,0 +1,162 @@
+#include <iostream>
+#include <getopt.h>
+#include <vector>
+#include <string>
+#include <optional>
+#include <filesystem>
+#include <fstream>
+#include <string.h>
+#include <cstdlib>
+#include <algorithm>
+
+#include "config.h"
+#include "utils.h"
+
+static struct option long_options[] = {
+    {"help",        no_argument,       NULL, 'h'},
+    {"format",      required_argument, NULL, 'f'},
+    {"output",      required_argument, NULL, 'o'},
+    {"dont-follow", no_argument,       NULL, 'e'},
+    {"icons",       required_argument, NULL, 'i'}
+};
+
+
+std::optional<std::filesystem::path> get_config_home() {
+    if (char *home = std::getenv("XDG_CONFIG_HOME"); home != nullptr)
+        return home;
+
+    if (char *home = std::getenv("HOME"); home != nullptr)
+        return std::filesystem::path(home) / ".config";
+
+
+    std::cerr << "Unable to get config home. Ignoring config." << std::endl;
+    return std::nullopt;
+}
+
+int _parse_format(ProgramOptions *opts) {
+    auto output_format = optarg_to_format();
+    if (!output_format) {
+        std::cerr << "Invalid format!\n"
+            << "Valid values are: waybar, custom, raw." << std::endl;
+
+        return 1;
+    }
+
+    opts->output_format = *output_format;
+    return -1;
+}
+
+int parse_config(ProgramOptions *opts) {
+    auto config_home = get_config_home();
+    if (!config_home) return -1;
+
+    std::filesystem::path config_file = *config_home / "cppbtbl" / "config";
+
+    // std::cerr << "[DEBUG] config_file_path = " << config_file << std::endl;
+
+    if (!std::filesystem::exists(config_file))
+        return -1;
+
+    std::ifstream file(config_file);
+    std::string line;
+
+    // first arg is program name, we don't need it
+    std::vector<const char*> _argv = { "cppbtbl" };
+    while (std::getline(file, line)) {
+        line.insert(0, "--");
+
+        const char *copy = strdup(line.c_str());
+        // std::cerr << static_cast<const void *>(line.c_str()) << ": " << line << std::endl;
+        _argv.push_back(std::move(copy));
+    }
+
+    // std::cerr << "[DEBUG] _argv.size() = " << _argv.size() << std::endl;
+
+    // reset getopt
+    optind = 1;
+    int opt;
+    while ((opt = getopt_long_only(
+        _argv.size(),
+        const_cast<char *const *>(_argv.data()),
+        "ef:o:i:",
+        long_options,
+        nullptr
+    )) != -1) {
+        //std::cerr << "[DEBUG] getopt_long_only opt=" << (char)opt << ", optarg=" << optarg << std::endl;
+        switch(opt) {
+            case 'f':
+                if (opts->output_format != format_raw_default) break;
+                if (int e = _parse_format(opts); e != -1)
+                    return e;
+                break;
+            case 'o':
+                if (opts->custom_format != nullptr) break; 
+                // i need a copy here, because the pointer gets free'd later on
+                opts->custom_format = strdup(optarg);
+                break;
+            case 'e':
+                opts->dont_follow = true;
+                break;
+            case 'i':
+                if (!opts->icons.empty()) break;
+                opts->icons = split(optarg, ',');
+                break;
+            default:
+                return 1;
+        }
+    }
+
+    // clear all duplicated strings
+    std::for_each(
+        ++_argv.begin(),
+        _argv.end(),
+        [opts](const char* ptr) {
+            // std::cerr << (void *)ptr << ": " << ptr << std::endl;
+            std::free((void *)ptr);
+            //std::cerr << "opts->custom_format: " << opts->custom_format << std::endl;
+        } 
+    );
+
+    return -1;
+}
+
+int parse_opts(int argc, char *const argv[], ProgramOptions *opts) {
+
+    // reset getopt
+    optind = 1;
+    int opt;
+    while ((opt = getopt_long(argc, argv, "hef:o:i:", long_options, nullptr)) != -1) {
+        switch (opt) {
+            case 'h':
+                help(argv[0]);
+                return 0;
+            case 'f':
+                if (int e = _parse_format(opts); e != -1)
+                    return e;
+                break;
+            case 'o':
+                opts->custom_format = std::move(optarg);
+                break;
+            case 'e':
+                opts->dont_follow = true;
+                break;
+            case 'i':
+                opts->icons = split(optarg, ',');
+                break;
+            default:
+                return 1;
+        }
+    }
+    if (int e = parse_config(opts); e != -1) {
+        std::cerr << "Error occurred while parsing config." << std::endl;
+        return 1;
+    }
+
+    if (opts->output_format == format_custom and
+        (!opts->custom_format or opts->icons.empty())) {
+        incorrect_format_usage(argv[0]);
+        return 1;
+    }
+
+    return -1;
+}

src/config.h

@@ -0,0 +1,19 @@
+#pragma once
+#include <vector>
+#include <string>
+
+enum OutputFormat {
+    format_raw_default, // when its the default value
+    format_raw,
+    format_waybar,
+    format_custom
+};
+
+struct ProgramOptions {
+    std::vector<std::string> icons;
+    OutputFormat output_format = format_raw_default;
+    char *custom_format;
+    bool dont_follow;
+};
+
+extern int parse_opts(int argc, char *const argv[], ProgramOptions *opts);