Started to work on process functions.

These aren't complete, but adding them now so they can be used.
As currently only thing to do is ensure we get CPU and memory usage for
a process.

sysinfo.odin

@@ -376,3 +376,122 @@ get_system_uptime_in_seconds :: proc() -> (int, bool) {
 
 	return uptime_seconds, true
 }
+
+get_total_number_of_processes :: proc () -> (int) {
+	fd, open_err := os.open("/proc")
+	if open_err != 0 {
+		return 0
+	}
+	defer os.close(fd)
+
+	files, err := os.read_dir(fd, -1)
+	if err != 0 {
+		return 0
+	}
+	defer os.file_info_slice_delete(files)
+
+	number_of_processes := 0
+	for file in files {
+		if file.is_dir && strconv.atoi(file.name) != 0 {
+			number_of_processes += 1
+		}
+	}
+
+	return number_of_processes
+}
+
+// https://www.baeldung.com/linux/total-process-cpu-usage
+get_process_details :: proc(pid: int) -> (Process, bool) {
+	process: Process
+
+	process.pid = pid
+
+	buf: [256]u8
+	filename := fmt.tprintf("/proc/%d/comm", pid)
+	fd, err := os.open(filename)
+	if err != os.ERROR_NONE {
+		return {}, false
+	}
+	_, err = os.read_full(fd, buf[0:])
+	if err != os.ERROR_NONE {
+		return {}, false
+	}
+	temp := string(buf[:])[:strings.index(string(buf[:]), "\n")]
+	process.name = strings.clone(temp)
+
+	filename = fmt.tprintf("/proc/%d/cmdline", pid)
+	fd, err = os.open(filename)
+	if err != os.ERROR_NONE {
+		return {}, false
+	}
+	_, err = os.read_full(fd, buf[0:])
+	if err != os.ERROR_NONE {
+		return {}, false
+	}
+	process.command = strings.clone(string(buf[:]))
+
+	// filename = fmt.tprintf("/proc/%d/stat", pid)
+	// fd, err = os.open(filename)
+	// if err != os.ERROR_NONE {
+	// 	return {}, false
+	// }
+	// _, err = os.read_full(fd, buf[0:])
+	// if err != os.ERROR_NONE {
+	// 	return {}, false
+	// }
+
+	// fields := strings.fields(string(buf))
+
+	// utime := strconv.atoi(fields[13])
+	// stime := strconv.atoi(fields[14])
+	// process_start_time := strconv.atoi(fields[21])
+
+	return process, true
+}
+
+get_processes :: proc() -> ([]Process, bool) {
+	fd, open_err := os.open("/proc")
+	if open_err != 0 {
+		return nil, false
+	}
+	defer os.close(fd)
+
+	files, err := os.read_dir(fd, -1)
+	if err != 0 {
+		return nil, false
+	}
+	defer os.file_info_slice_delete(files)
+
+	processes: [dynamic]Process
+	process: Process
+	ok: bool
+	current_process := 0
+	for file in files {
+		if file.is_dir && strconv.atoi(file.name) != 0 {
+			process, ok = get_process_details(strconv.atoi(file.name))
+			if !ok {
+				delete(processes)
+				return nil, false
+			}
+
+			append(&processes, process)
+
+			current_process += 1
+		}
+	}
+
+	return processes[:], true
+}
+
+process_delete :: proc(process: Process, allocator := context.allocator) {
+	delete(process.name)
+	delete(process.command)
+}
+
+process_slice_delete :: proc(processes: []Process, allocator := context.allocator) {
+	for process in processes {
+		process_delete(process, allocator)
+	}
+
+	delete(processes, allocator)
+}