LibCore: Move Core::Stream::File::exists() to Core::File

`Core::Stream::File` shouldn't hold any utility methods that are
unrelated to constructing a `Core::Stream`, so let's just replace the
existing `Core::File::exists` with the nicer looking implementation.

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateEmojiData.cpp

@@ -12,6 +12,7 @@
 #include <AK/Types.h>
 #include <LibCore/ArgsParser.h>
 #include <LibCore/Directory.h>
+#include <LibCore/File.h>
 #include <LibCore/Stream.h>
 #include <LibUnicode/Emoji.h>
 
@@ -45,7 +46,7 @@ static void set_image_path_for_emoji(StringView emoji_resource_path, Emoji& emoj
     }
 
     auto path = DeprecatedString::formatted("{}/{}.png", emoji_resource_path, builder.build());
-    if (Core::Stream::File::exists(path))
+    if (Core::File::exists(path))
         emoji.image_path = move(path);
 }
 
@@ -339,7 +340,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     args_parser.parse(arguments);
 
     auto emoji_test_file = TRY(open_file(emoji_test_path, Core::Stream::OpenMode::Read));
-    VERIFY(!emoji_resource_path.is_empty() && Core::Stream::File::exists(emoji_resource_path));
+    VERIFY(!emoji_resource_path.is_empty() && Core::File::exists(emoji_resource_path));
 
     EmojiData emoji_data {};
     TRY(parse_emoji_test_data(*emoji_test_file, emoji_data));

Meta/Lagom/Tools/ConfigureComponents/main.cpp

@@ -234,7 +234,7 @@ int main()
         return 1;
     }
 
-    if (!Core::File::exists("components.ini")) {
+    if (!Core::File::exists("components.ini"sv)) {
         warnln("\e[31mError:\e[0m There is no 'components.ini' in the current working directory.");
         warnln("       It can be generated by running CMake with 'cmake ../.. -G Ninja'");
         return 1;

Tests/LibTLS/TestTLSHandshake.cpp

@@ -12,7 +12,7 @@
 #include <LibTLS/TLSv12.h>
 #include <LibTest/TestCase.h>
 
-static char const* ca_certs_file = "./ca_certs.ini";
+static StringView ca_certs_file = "./ca_certs.ini"sv;
 static int port = 443;
 
 constexpr auto DEFAULT_SERVER = "www.google.com"sv;

Userland/Applications/Spreadsheet/main.cpp

@@ -38,7 +38,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
     args_parser.parse(arguments);
 
     if (filename) {
-        if (!Core::File::exists(filename) || Core::File::is_directory(filename)) {
+        if (!Core::File::exists({ filename, strlen(filename) }) || Core::File::is_directory(filename)) {
             warnln("File does not exist or is a directory: {}", filename);
             return 1;
         }

Userland/Libraries/LibCore/File.cpp

@@ -9,6 +9,7 @@
 #include <AK/ScopeGuard.h>
 #include <LibCore/DirIterator.h>
 #include <LibCore/File.h>
+#include <LibCore/System.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <libgen.h>
@@ -191,10 +192,9 @@ bool File::looks_like_shared_library(DeprecatedString const& filename)
     return filename.ends_with(".so"sv) || filename.contains(".so."sv);
 }
 
-bool File::exists(DeprecatedString const& filename)
+bool File::exists(StringView filename)
 {
-    struct stat st;
+    return !Core::System::stat(filename).is_error();
-    return stat(filename.characters(), &st) == 0;
 }
 
 ErrorOr<size_t> File::size(DeprecatedString const& filename)

Userland/Libraries/LibCore/File.h

@@ -47,7 +47,7 @@ public:
     bool looks_like_shared_library() const;
     static bool looks_like_shared_library(DeprecatedString const& filename);
 
-    static bool exists(DeprecatedString const& filename);
+    static bool exists(StringView filename);
     static ErrorOr<size_t> size(DeprecatedString const& filename);
     static DeprecatedString current_working_directory();
     static DeprecatedString absolute_path(DeprecatedString const& path);

Userland/Libraries/LibCore/Stream.cpp

@@ -165,11 +165,6 @@ ErrorOr<NonnullOwnPtr<File>> File::adopt_fd(int fd, OpenMode mode, ShouldCloseFi
     return file;
 }
 
-bool File::exists(StringView filename)
-{
-    return !Core::System::stat(filename).is_error();
-}
-
 ErrorOr<NonnullOwnPtr<File>> File::standard_input()
 {
     return File::adopt_fd(STDIN_FILENO, OpenMode::Read, ShouldCloseFileDescriptor::No);

Userland/Libraries/LibCore/Stream.h

@@ -220,7 +220,6 @@ class File final : public SeekableStream {
 public:
     static ErrorOr<NonnullOwnPtr<File>> open(StringView filename, OpenMode, mode_t = 0644);
     static ErrorOr<NonnullOwnPtr<File>> adopt_fd(int fd, OpenMode, ShouldCloseFileDescriptor = ShouldCloseFileDescriptor::Yes);
-    static bool exists(StringView filename);
 
     static ErrorOr<NonnullOwnPtr<File>> standard_input();
     static ErrorOr<NonnullOwnPtr<File>> standard_output();

Userland/Services/WebContent/main.cpp

@@ -6,6 +6,7 @@
 
 #include "ImageCodecPluginSerenity.h"
 #include <LibCore/EventLoop.h>
+#include <LibCore/File.h>
 #include <LibCore/LocalServer.h>
 #include <LibCore/Stream.h>
 #include <LibCore/System.h>
@@ -26,7 +27,7 @@ ErrorOr<int> serenity_main(Main::Arguments)
     TRY(Core::System::pledge("stdio recvfd sendfd accept unix rpath"));
 
     // This must be first; we can't check if /tmp/webdriver exists once we've unveiled other paths.
-    if (Core::Stream::File::exists("/tmp/webdriver"sv))
+    if (Core::File::exists("/tmp/webdriver"sv))
         TRY(Core::System::unveil("/tmp/webdriver", "rw"));
 
     TRY(Core::System::unveil("/sys/kernel/processes", "r"));

Userland/Utilities/touch.cpp

@@ -9,7 +9,7 @@
 #include <AK/GenericLexer.h>
 #include <AK/Time.h>
 #include <LibCore/ArgsParser.h>
-#include <LibCore/Stream.h>
+#include <LibCore/File.h>
 #include <LibCore/System.h>
 #include <LibMain/Main.h>
 #include <LibTimeZone/TimeZone.h>
@@ -239,7 +239,7 @@ ErrorOr<int> serenity_main(Main::Arguments arguments)
         atime.tv_nsec = UTIME_OMIT;
 
     for (auto path : paths) {
-        if (Core::Stream::File::exists(path)) {
+        if (Core::File::exists(path)) {
             if (utimensat(AT_FDCWD, path.characters(), times, 0) == -1)
                 err("failed to touch '{}': {}", path, strerror(errno));
         } else if (!no_create_file) {