libos: Make long value arguments use '=' and make value arguments' values always required

apps/date.cpp

@@ -11,8 +11,7 @@ Result<int> luna_main(int argc, char** argv)
     os::ArgumentParser parser;
     parser.add_description("Display the current (or another) date and time."_sv);
     parser.add_system_program_info("date"_sv);
-    parser.add_value_argument(date, 'd', "date"_sv, true,
-                              "the UNIX timestamp to display instead of the current time"_sv);
+    parser.add_value_argument(date, 'd', "date"_sv, "the UNIX timestamp to display instead of the current time"_sv);
     parser.parse(argc, argv);
 
     time_t now;

apps/ls.cpp

@@ -96,7 +96,7 @@ Result<int> luna_main(int argc, char** argv)
                                "follow symbolic links listed as arguments"_sv);
     parser.add_switch_argument(one_per_line, '1', ""_sv, "list one file per line"_sv);
     parser.add_switch_argument(list_directories, 'd', "directory"_sv, "list directories instead of their contents"_sv);
-    parser.add_value_argument(sort_type, ' ', "sort"_sv, true, "sort by name, size or time"_sv);
+    parser.add_value_argument(sort_type, ' ', "sort"_sv, "sort by name, size or time"_sv);
     parser.add_switch_argument(reverse_sort, 'r', "reverse"_sv, "reverse order while sorting"_sv);
     parser.parse(argc, argv);
 

apps/mkdir.cpp

@@ -41,7 +41,7 @@ Result<int> luna_main(int argc, char** argv)
     parser.add_description("Create directories."_sv);
     parser.add_system_program_info("mkdir"_sv);
     parser.add_positional_argument(path, "path"_sv, true);
-    parser.add_value_argument(mode_string, 'm', "mode"_sv, true, "set the mode for the newly created directory");
+    parser.add_value_argument(mode_string, 'm', "mode"_sv, "set the mode for the newly created directory");
     parser.add_switch_argument(recursive, 'p', "parents"_sv,
                                "if parent directories do not exist, create them as well"_sv);
     parser.parse(argc, argv);

apps/mount.cpp

@@ -5,13 +5,13 @@
 Result<int> luna_main(int argc, char** argv)
 {
     StringView target;
-    StringView fstype;
+    StringView fstype { "auto" };
 
     os::ArgumentParser parser;
     parser.add_description("Mount a file system.");
     parser.add_system_program_info("mount"_sv);
     parser.add_positional_argument(target, "mountpoint"_sv, true);
-    parser.add_value_argument(fstype, 't', "type"_sv, "auto"_sv, "the file system type to use");
+    parser.add_value_argument(fstype, 't', "type"_sv, "the file system type to use");
     parser.parse(argc, argv);
 
     if (mount(target.chars(), fstype.chars()) < 0)

apps/sh.cpp

@@ -48,7 +48,7 @@ Result<int> luna_main(int argc, char** argv)
     parser.add_description("The Luna system's command shell."_sv);
     parser.add_system_program_info("sh"_sv);
     parser.add_positional_argument(path, "path"_sv, "-"_sv);
-    parser.add_value_argument(command, 'c', "command"_sv, true, "execute a single command and then exit"_sv);
+    parser.add_value_argument(command, 'c', "command"_sv, "execute a single command and then exit"_sv);
     parser.parse(argc, argv);
 
     if (!command.is_empty()) TRY(execute_command(command));

apps/sysfuzz.cpp

@@ -40,8 +40,8 @@ int main(int argc, char** argv)
     os::ArgumentParser parser;
     parser.add_description("System call fuzzer (invokes system calls with random arguments to test system stability)");
     parser.add_system_program_info("sysfuzz"_sv);
-    parser.add_value_argument(times_sv, 't', "times"_sv, true, "the number of syscalls to invoke"_sv);
-    parser.add_value_argument(interval_sv, 'i', "interval"_sv, true,
+    parser.add_value_argument(times_sv, 't', "times"_sv, "the number of syscalls to invoke"_sv);
+    parser.add_value_argument(interval_sv, 'i', "interval"_sv,
                               "the interval between system calls (in milliseconds)"_sv);
     parser.parse(argc, argv);
 

libluna/include/luna/StringView.h

@@ -42,6 +42,9 @@ class StringView
 
     Result<Vector<String>> split(StringView delim) const;
     Result<Vector<String>> split_once(char delim) const;
+    Result<Vector<StringView>> split_view(char delim) const;
+
+    bool contains(char v) const;
 
     static StringView from_fixed_size_cstring(const char* string, usize max);
 

libluna/src/StringView.cpp

@@ -50,12 +50,12 @@ const char& StringView::operator[](usize index) const
 
 bool StringView::operator==(const char* other) const
 {
-    return !strcmp(m_string, other);
+    return !strncmp(m_string, other, m_length);
 }
 
 bool StringView::operator==(StringView other) const
 {
-    return !strcmp(m_string, other.m_string);
+    return !strncmp(m_string, other.m_string, m_length);
 }
 
 Result<Vector<String>> StringView::split(StringView delim) const
@@ -110,6 +110,32 @@ Result<Vector<String>> StringView::split_once(char delim) const
     return result;
 }
 
+Result<Vector<StringView>> StringView::split_view(char delim) const
+{
+    Vector<StringView> result;
+
+    char* middle = strchr(m_string, delim);
+    if (!middle)
+    {
+        TRY(result.try_append(*this));
+        return result;
+    }
+
+    // begin will not contain a null terminator.
+    auto begin = StringView::from_fixed_size_cstring(m_string, middle - m_string);
+    auto end = StringView { middle + 1 };
+
+    TRY(result.try_append(begin));
+    TRY(result.try_append(end));
+
+    return result;
+}
+
+bool StringView::contains(char v) const
+{
+    return strchr(m_string, v);
+}
+
 Result<usize> StringView::to_uint() const
 {
     const char* endptr = nullptr;

libos/include/os/ArgumentParser.h

@@ -78,32 +78,10 @@ namespace os
          * @param long_flag The long flag to use for this argument, excluding the '--' prefix: an option '--example'
          * would be passed as 'example'. Can be a string of any length. If you do not wish this argument to have a long
          * flag, use an empty string: "".
-         * @param fallback The value to use if the user uses the argument but does not provide a value. If, however, the
-         * user does not specify this argument at all, out WILL NOT BE MODIFIED!
          * @param help The help text to show for this argument (optional).
          * @return Result<void> Whether the operation succeeded.
          */
-        Result<void> add_value_argument(StringView& out, char short_flag, StringView long_flag, StringView fallback,
-                                        StringView help = {});
-
-        /**
-         * @brief Register a new value argument.
-         *
-         * @param out The variable where the argument's value will be stored.
-         * @param short_flag The short flag to use for this argument, excluding the '-' prefix: an option '-c' would be
-         * passed as 'c'. Can only be a single ASCII character. If you do not wish this argument to have a short flag,
-         * use the space character: ' '.
-         * @param long_flag The long flag to use for this argument, excluding the '--' prefix: an option '--example'
-         * would be passed as 'example'. Can be a string of any length. If you do not wish this argument to have a long
-         * flag, use an empty string: "".
-         * @param value_required Whether the user is required to pass a value when using this argument. If this is
-         * false and the user does not enter a value along with the argument, out will be set to an empty string. If,
-         * however, the user does not specify this argument at all, out WILL NOT BE MODIFIED!
-         * @param help The help text to show for this argument (optional).
-         * @return Result<void> Whether the operation succeeded.
-         */
-        Result<void> add_value_argument(StringView& out, char short_flag, StringView long_flag, bool value_required,
-                                        StringView help = {});
+        Result<void> add_value_argument(StringView& out, char short_flag, StringView long_flag, StringView help = {});
 
         /**
          * @brief Set the vector to append extra unregistered positional arguments to, after all
@@ -192,8 +170,6 @@ namespace os
             StringView* out;
             char short_flag;
             StringView long_flag;
-            bool required;
-            StringView fallback;
             StringView help;
         };
 

libos/src/ArgumentParser.cpp

@@ -8,6 +8,7 @@
  */
 
 #include <luna/StringBuilder.h>
+#include <luna/TypeTraits.h>
 #include <os/ArgumentParser.h>
 #include <os/File.h>
 #include <stdio.h>
@@ -52,22 +53,9 @@ namespace os
     }
 
     Result<void> ArgumentParser::add_value_argument(StringView& out, char short_flag, StringView long_flag,
-                                                    bool value_required, StringView help)
+                                                    StringView help)
     {
-        ValueArgument arg { &out, short_flag, long_flag, value_required, {}, help };
-
-        if (short_flag == 'h') m_add_short_help_flag = false;
-        if (long_flag == "help"_sv) m_add_long_help_flag = false;
-        if (short_flag == 'v') m_add_short_version_flag = false;
-        if (long_flag == "version"_sv) m_add_long_version_flag = false;
-
-        return m_value_args.try_append(move(arg));
-    }
-
-    Result<void> ArgumentParser::add_value_argument(StringView& out, char short_flag, StringView long_flag,
-                                                    StringView fallback, StringView help)
-    {
-        ValueArgument arg { &out, short_flag, long_flag, false, fallback, help };
+        ValueArgument arg { &out, short_flag, long_flag, help };
 
         if (short_flag == 'h') m_add_short_help_flag = false;
         if (long_flag == "help"_sv) m_add_long_help_flag = false;
@@ -130,6 +118,8 @@ namespace os
 
         bool is_still_parsing_flags = true;
 
+        Vector<PositionalArgument> positional_args = TRY(m_positional_args.deep_copy());
+
         for (int i = 1; i < argc; i++)
         {
             StringView arg = argv[i];
@@ -168,16 +158,21 @@ namespace os
                         }
                     }
 
+                    if (flag.contains('='))
+                    {
+                        auto v = TRY(flag.split_view('='));
+                        StringView actual_flag = v[0];
+                        StringView data = v[1];
                         for (const auto& current : m_value_args)
                         {
-                        if (current.long_flag == flag)
+                            if (current.long_flag == actual_flag)
                             {
-                            current_value_argument = current;
-                            is_parsing_value_argument = true;
+                                *current.out = data;
                                 found = true;
                                 break;
                             }
                         }
+                    }
 
                     if (found) continue;
 
@@ -237,7 +232,7 @@ namespace os
                 }
             }
 
-            Option<PositionalArgument> current = m_positional_args.try_dequeue();
+            Option<PositionalArgument> current = positional_args.try_dequeue();
             if (!current.has_value())
             {
                 if (m_vector_argument)
@@ -253,17 +248,13 @@ namespace os
 
         if (is_parsing_value_argument)
         {
-            if (current_value_argument->required)
-            {
-                os::eprintln("%s: option '--%s' requires an argument", program_name.chars(),
-                             current_value_argument->long_flag.chars());
+            os::eprintln("%s: option '-%c' requires an argument", program_name.chars(),
+                         current_value_argument->short_flag);
             short_usage(program_name);
         }
-            else { *current_value_argument->out = current_value_argument->fallback; }
-        }
 
         // Loop through all remaining positional arguments.
-        for (const auto& arg : m_positional_args)
+        for (const auto& arg : positional_args)
         {
             if (arg.required)
             {
@@ -317,10 +308,7 @@ namespace os
 
         for (const auto& arg : m_value_args)
         {
-            StringView value_name;
-            if (arg.required) value_name = "VALUE"_sv;
-            else
-                value_name = "[VALUE]"_sv;
+            StringView value_name = "VALUE"_sv;
 
             int field_size = 20 - (int)(arg.long_flag.length() + 1);
             if (field_size < 0) field_size = 0;
@@ -333,11 +321,11 @@ namespace os
             }
             else if (arg.short_flag == ' ')
             {
-                printf("      --%s %-*s %s\n", arg.long_flag.chars(), field_size, value_name.chars(), arg.help.chars());
+                printf("      --%s=%-*s %s\n", arg.long_flag.chars(), field_size, value_name.chars(), arg.help.chars());
             }
             else
             {
-                printf("  -%c, --%s %-*s %s\n", arg.short_flag, arg.long_flag.chars(), field_size, value_name.chars(),
+                printf("  -%c, --%s=%-*s %s\n", arg.short_flag, arg.long_flag.chars(), field_size, value_name.chars(),
                        arg.help.chars());
             }
         }