LocateUri: new library to classify URIs in a standard way

5 files changed, 205 insertions, 151 deletions

diff --git a/src/command/CommandError.cxx b/src/command/CommandError.cxx
index d95722c3b..9f06431b4 100644
--- a/src/command/CommandError.cxx
+++ b/src/command/CommandError.cxx
@@ -20,6 +20,7 @@
 #include "config.h"
 #include "CommandError.hxx"
 #include "db/DatabaseError.hxx"
+#include "LocateUri.hxx"
 #include "client/Response.hxx"
 #include "util/Error.hxx"
 #include "Log.hxx"
@@ -114,6 +115,9 @@ print_error(Response &r, const Error &error)
 			return CommandResult::ERROR;
 		}
 #endif
+	} else if (error.IsDomain(locate_uri_domain)) {
+		r.Error(ACK_ERROR_ARG, error.GetMessage());
+		return CommandResult::ERROR;
 	} else if (error.IsDomain(errno_domain)) {
 		r.Error(ACK_ERROR_SYSTEM, strerror(error.GetCode()));
 		return CommandResult::ERROR;
diff --git a/src/command/FileCommands.cxx b/src/command/FileCommands.cxx
index f7e16a0d2..486c00d89 100644
--- a/src/command/FileCommands.cxx
+++ b/src/command/FileCommands.cxx
@@ -39,8 +39,8 @@
 #include "fs/AllocatedPath.hxx"
 #include "fs/FileInfo.hxx"
 #include "fs/DirectoryReader.hxx"
+#include "LocateUri.hxx"
 #include "TimePrint.hxx"
-#include "ls.hxx"
 
 #include <assert.h>
 #include <sys/stat.h>
@@ -70,21 +70,12 @@ skip_path(Path name_fs)
 #endif
 
 CommandResult
-handle_listfiles_local(Client &client, Response &r,
-		       const char *path_utf8)
+handle_listfiles_local(Response &r,
+		       const char *path_utf8, Path path_fs)
 {
-	const auto path_fs = AllocatedPath::FromUTF8(path_utf8);
-	if (path_fs.IsNull()) {
-		r.Error(ACK_ERROR_NO_EXIST, "unsupported file name");
-		return CommandResult::ERROR;
-	}
-
-	Error error;
-	if (!client.AllowFile(path_fs, error))
-		return print_error(r, error);
-
 	DirectoryReader reader(path_fs);
 	if (reader.HasFailed()) {
+		Error error;
 		error.FormatErrno("Failed to open '%s'", path_utf8);
 		return print_error(r, error);
 	}
@@ -172,11 +163,6 @@ static constexpr tag_handler print_comment_handler = {
 static CommandResult
 read_stream_comments(Response &r, const char *uri)
 {
-	if (!uri_supported_scheme(uri)) {
-		r.Error(ACK_ERROR_NO_EXIST, "unsupported URI scheme");
-		return CommandResult::ERROR;
-	}
-
 	if (!tag_stream_scan(uri, print_comment_handler, &r)) {
 		r.Error(ACK_ERROR_NO_EXIST, "Failed to load file");
 		return CommandResult::ERROR;
@@ -201,63 +187,64 @@ read_file_comments(Response &r, const Path path_fs)
 
 }
 
-static const char *
-translate_uri(const char *uri)
+static CommandResult
+read_db_comments(Client &client, Response &r, const char *uri)
 {
-	if (memcmp(uri, "file:///", 8) == 0)
-		/* drop the "file://", leave only an absolute path
-		   (starting with a slash) */
-		return uri + 7;
+#ifdef ENABLE_DATABASE
+	const Storage *storage = client.GetStorage();
+	if (storage == nullptr) {
+#else
+		(void)client;
+		(void)uri;
+#endif
+		r.Error(ACK_ERROR_NO_EXIST, "No database");
+		return CommandResult::ERROR;
+#ifdef ENABLE_DATABASE
+	}
+
+	{
+		AllocatedPath path_fs = storage->MapFS(uri);
+		if (!path_fs.IsNull())
+			return read_file_comments(r, path_fs);
+	}
 
-	return uri;
+	{
+		const std::string uri2 = storage->MapUTF8(uri);
+		if (uri_has_scheme(uri2.c_str()))
+			return read_stream_comments(r, uri2.c_str());
+	}
+
+	r.Error(ACK_ERROR_NO_EXIST, "No such file");
+	return CommandResult::ERROR;
+#endif
 }
 
 CommandResult
 handle_read_comments(Client &client, Request args, Response &r)
 {
 	assert(args.size == 1);
-	const char *const uri = translate_uri(args.front());
-
-	if (PathTraitsUTF8::IsAbsolute(uri)) {
-		/* read comments from arbitrary local file */
-		const char *path_utf8 = uri;
-		AllocatedPath path_fs = AllocatedPath::FromUTF8(path_utf8);
-		if (path_fs.IsNull()) {
-			r.Error(ACK_ERROR_NO_EXIST, "unsupported file name");
-			return CommandResult::ERROR;
-		}
 
-		Error error;
-		if (!client.AllowFile(path_fs, error))
-			return print_error(r, error);
+	const char *const uri = args.front();
 
-		return read_file_comments(r, path_fs);
-	} else if (uri_has_scheme(uri)) {
-		return read_stream_comments(r, uri);
-	} else {
+	Error error;
+	const auto located_uri = LocateUri(uri, &client,
 #ifdef ENABLE_DATABASE
-		const Storage *storage = client.GetStorage();
-		if (storage == nullptr) {
+					   nullptr,
 #endif
-			r.Error(ACK_ERROR_NO_EXIST, "No database");
-			return CommandResult::ERROR;
-#ifdef ENABLE_DATABASE
-		}
+					   error);
+	switch (located_uri.type) {
+	case LocatedUri::Type::UNKNOWN:
+		return print_error(r, error);
 
-		{
-			AllocatedPath path_fs = storage->MapFS(uri);
-			if (!path_fs.IsNull())
-				return read_file_comments(r, path_fs);
-		}
+	case LocatedUri::Type::ABSOLUTE:
+		return read_stream_comments(r, located_uri.canonical_uri);
 
-		{
-			const std::string uri2 = storage->MapUTF8(uri);
-			if (uri_has_scheme(uri2.c_str()))
-				return read_stream_comments(r, uri2.c_str());
-		}
+	case LocatedUri::Type::RELATIVE:
+		return read_db_comments(client, r, located_uri.canonical_uri);
 
-		r.Error(ACK_ERROR_NO_EXIST, "No such file");
-		return CommandResult::ERROR;
-#endif
+	case LocatedUri::Type::PATH:
+		return read_file_comments(r, located_uri.path);
 	}
+
+	gcc_unreachable();
 }
diff --git a/src/command/FileCommands.hxx b/src/command/FileCommands.hxx
index c072d2028..9c6631df5 100644
--- a/src/command/FileCommands.hxx
+++ b/src/command/FileCommands.hxx
@@ -25,10 +25,11 @@
 class Client;
 class Request;
 class Response;
+class Path;
 
 CommandResult
-handle_listfiles_local(Client &client, Response &response,
-		       const char *path_utf8);
+handle_listfiles_local(Response &response,
+		       const char *path_utf8, Path path_fs);
 
 CommandResult
 handle_read_comments(Client &client, Request request, Response &response);
diff --git a/src/command/OtherCommands.cxx b/src/command/OtherCommands.cxx
index 09b951b03..b4a23fe4b 100644
--- a/src/command/OtherCommands.cxx
+++ b/src/command/OtherCommands.cxx
@@ -25,6 +25,7 @@
 #include "CommandError.hxx"
 #include "db/Uri.hxx"
 #include "storage/StorageInterface.hxx"
+#include "LocateUri.hxx"
 #include "DetachedSong.hxx"
 #include "SongPrint.hxx"
 #include "TagPrint.hxx"
@@ -122,31 +123,49 @@ handle_listfiles(Client &client, Request args, Response &r)
 	/* default is root directory */
 	const auto uri = args.GetOptional(0, "");
 
-	if (memcmp(uri, "file:///", 8) == 0)
-		/* list local directory */
-		return handle_listfiles_local(client, r, uri + 7);
-
+	Error error;
+	const auto located_uri = LocateUri(uri, &client,
 #ifdef ENABLE_DATABASE
-	if (uri_has_scheme(uri))
-		/* use storage plugin to list remote directory */
-		return handle_listfiles_storage(r, uri);
+					   nullptr,
+#endif
+					   error);
 
-	/* must be a path relative to the configured
-	   music_directory */
+	switch (located_uri.type) {
+	case LocatedUri::Type::UNKNOWN:
+		return print_error(r, error);
 
-	if (client.partition.instance.storage != nullptr)
-		/* if we have a storage instance, obtain a list of
-		   files from it */
-		return handle_listfiles_storage(r,
-						*client.partition.instance.storage,
-						uri);
+	case LocatedUri::Type::ABSOLUTE:
+#ifdef ENABLE_DATABASE
+		/* use storage plugin to list remote directory */
+		return handle_listfiles_storage(r, located_uri.canonical_uri);
+#else
+		r.Error(ACK_ERROR_NO_EXIST, "No database");
+		return CommandResult::ERROR;
+#endif
 
-	/* fall back to entries from database if we have no storage */
-	return handle_listfiles_db(client, r, uri);
+	case LocatedUri::Type::RELATIVE:
+#ifdef ENABLE_DATABASE
+		if (client.partition.instance.storage != nullptr)
+			/* if we have a storage instance, obtain a list of
+			   files from it */
+			return handle_listfiles_storage(r,
+							*client.partition.instance.storage,
+							uri);
+
+		/* fall back to entries from database if we have no storage */
+		return handle_listfiles_db(client, r, uri);
 #else
-	r.Error(ACK_ERROR_NO_EXIST, "No database");
-	return CommandResult::ERROR;
+		r.Error(ACK_ERROR_NO_EXIST, "No database");
+		return CommandResult::ERROR;
 #endif
+
+	case LocatedUri::Type::PATH:
+		/* list local directory */
+		return handle_listfiles_local(r, located_uri.canonical_uri,
+					      located_uri.path);
+	}
+
+	gcc_unreachable();
 }
 
 static constexpr tag_handler print_tag_handler = {
@@ -155,54 +174,26 @@ static constexpr tag_handler print_tag_handler = {
 	nullptr,
 };
 
-CommandResult
-handle_lsinfo(Client &client, Request args, Response &r)
+static CommandResult
+handle_lsinfo_absolute(Response &r, const char *uri)
 {
-	/* default is root directory */
-	const auto uri = args.GetOptional(0, "");
-
-	if (memcmp(uri, "file:///", 8) == 0) {
-		/* print information about an arbitrary local file */
-		const char *path_utf8 = uri + 7;
-		const auto path_fs = AllocatedPath::FromUTF8(path_utf8);
-
-		if (path_fs.IsNull()) {
-			r.Error(ACK_ERROR_NO_EXIST, "unsupported file name");
-			return CommandResult::ERROR;
-		}
-
-		Error error;
-		if (!client.AllowFile(path_fs, error))
-			return print_error(r, error);
-
-		DetachedSong song(path_utf8);
-		if (!song.LoadFile(path_fs)) {
-			r.Error(ACK_ERROR_NO_EXIST, "No such file");
-			return CommandResult::ERROR;
-		}
-
-		song_print_info(r, client.partition, song);
-		return CommandResult::OK;
+	if (!tag_stream_scan(uri, print_tag_handler, &r)) {
+		r.Error(ACK_ERROR_NO_EXIST, "No such file");
+		return CommandResult::ERROR;
 	}
 
-	if (uri_has_scheme(uri)) {
-		if (!uri_supported_scheme(uri)) {
-			r.Error(ACK_ERROR_NO_EXIST, "unsupported URI scheme");
-			return CommandResult::ERROR;
-		}
-
-		if (!tag_stream_scan(uri, print_tag_handler, &r)) {
-			r.Error(ACK_ERROR_NO_EXIST, "No such file");
-			return CommandResult::ERROR;
-		}
-
-		return CommandResult::OK;
-	}
+	return CommandResult::OK;
+}
 
+static CommandResult
+handle_lsinfo_relative(Client &client, Response &r, const char *uri)
+{
 #ifdef ENABLE_DATABASE
 	CommandResult result = handle_lsinfo2(client, uri, r);
 	if (result != CommandResult::OK)
 		return result;
+#else
+	(void)client;
 #endif
 
 	if (isRootDirectory(uri)) {
@@ -219,6 +210,53 @@ handle_lsinfo(Client &client, Request args, Response &r)
 	return CommandResult::OK;
 }
 
+static CommandResult
+handle_lsinfo_path(Client &client, Response &r,
+		   const char *path_utf8, Path path_fs)
+{
+	DetachedSong song(path_utf8);
+	if (!song.LoadFile(path_fs)) {
+		r.Error(ACK_ERROR_NO_EXIST, "No such file");
+		return CommandResult::ERROR;
+	}
+
+	song_print_info(r, client.partition, song);
+	return CommandResult::OK;
+}
+
+CommandResult
+handle_lsinfo(Client &client, Request args, Response &r)
+{
+	/* default is root directory */
+	const auto uri = args.GetOptional(0, "");
+
+	Error error;
+	const auto located_uri = LocateUri(uri, &client,
+#ifdef ENABLE_DATABASE
+					   nullptr,
+#endif
+					   error);
+
+	switch (located_uri.type) {
+	case LocatedUri::Type::UNKNOWN:
+		return print_error(r, error);
+
+	case LocatedUri::Type::ABSOLUTE:
+		return handle_lsinfo_absolute(r, located_uri.canonical_uri);
+
+	case LocatedUri::Type::RELATIVE:
+		return handle_lsinfo_relative(client, r,
+					      located_uri.canonical_uri);
+
+	case LocatedUri::Type::PATH:
+		/* print information about an arbitrary local file */
+		return handle_lsinfo_path(client, r, located_uri.canonical_uri,
+					  located_uri.path);
+	}
+
+	gcc_unreachable();
+}
+
 #ifdef ENABLE_DATABASE
 
 static CommandResult
diff --git a/src/command/QueueCommands.cxx b/src/command/QueueCommands.cxx
index 1698e88df..7751aa26d 100644
--- a/src/command/QueueCommands.cxx
+++ b/src/command/QueueCommands.cxx
@@ -25,13 +25,14 @@
 #include "db/Selection.hxx"
 #include "SongFilter.hxx"
 #include "SongLoader.hxx"
+#include "DetachedSong.hxx"
+#include "LocateUri.hxx"
 #include "queue/Playlist.hxx"
 #include "PlaylistPrint.hxx"
 #include "client/Client.hxx"
 #include "client/Response.hxx"
 #include "Partition.hxx"
 #include "BulkEdit.hxx"
-#include "ls.hxx"
 #include "util/ConstBuffer.hxx"
 #include "util/UriUtil.hxx"
 #include "util/NumberParser.hxx"
@@ -42,15 +43,42 @@
 
 #include <string.h>
 
-static const char *
-translate_uri(const char *uri)
+static CommandResult
+AddUri(Client &client, const LocatedUri &uri, Response &r)
 {
-	if (memcmp(uri, "file:///", 8) == 0)
-		/* drop the "file://", leave only an absolute path
-		   (starting with a slash) */
-		return uri + 7;
+	Error error;
+	DetachedSong *song = SongLoader(client).LoadSong(uri, error);
+	if (song == nullptr)
+		return print_error(r, error);
+
+	auto &partition = client.partition;
+	unsigned id = partition.playlist.AppendSong(partition.pc,
+						    std::move(*song), error);
+	delete song;
+	if (id == 0)
+		return print_error(r, error);
 
-	return uri;
+	return CommandResult::OK;
+}
+
+static CommandResult
+AddDatabaseSelection(Client &client, const char *uri, Response &r)
+{
+#ifdef ENABLE_DATABASE
+	const ScopeBulkEdit bulk_edit(client.partition);
+
+	const DatabaseSelection selection(uri, true);
+	Error error;
+	return AddFromDatabase(client.partition, selection, error)
+		? CommandResult::OK
+		: print_error(r, error);
+#else
+	(void)client;
+	(void)uri;
+
+	r.Error(ACK_ERROR_NO_EXIST, "No database");
+	return CommandResult::ERROR;
+#endif
 }
 
 CommandResult
@@ -65,36 +93,32 @@ handle_add(Client &client, Request args, Response &r)
 		   here */
 		uri = "";
 
-	uri = translate_uri(uri);
+	Error error;
+	const auto located_uri = LocateUri(uri, &client,
+#ifdef ENABLE_DATABASE
+					   nullptr,
+#endif
+					   error);
+	switch (located_uri.type) {
+	case LocatedUri::Type::UNKNOWN:
+		return print_error(r, error);
 
-	if (uri_has_scheme(uri) || PathTraitsUTF8::IsAbsolute(uri)) {
-		const SongLoader loader(client);
-		Error error;
-		unsigned id = client.partition.AppendURI(loader, uri, error);
-		if (id == 0)
-			return print_error(r, error);
+	case LocatedUri::Type::ABSOLUTE:
+	case LocatedUri::Type::PATH:
+		return AddUri(client, located_uri, r);
 
-		return CommandResult::OK;
+	case LocatedUri::Type::RELATIVE:
+		return AddDatabaseSelection(client, located_uri.canonical_uri,
+					    r);
 	}
 
-#ifdef ENABLE_DATABASE
-	const ScopeBulkEdit bulk_edit(client.partition);
-
-	const DatabaseSelection selection(uri, true);
-	Error error;
-	return AddFromDatabase(client.partition, selection, error)
-		? CommandResult::OK
-		: print_error(r, error);
-#else
-	r.Error(ACK_ERROR_NO_EXIST, "No database");
-	return CommandResult::ERROR;
-#endif
+	gcc_unreachable();
 }
 
 CommandResult
 handle_addid(Client &client, Request args, Response &r)
 {
-	const char *const uri = translate_uri(args.front());
+	const char *const uri = args.front();
 
 	const SongLoader loader(client);
 	Error error;