tag/VorbisComment: use struct StringView

src/lib/xiph/FlacStreamMetadata.cxx

@@ -68,11 +68,12 @@ flac_parse_mixramp(const FLAC__StreamMetadata_VorbisComment &vc)
  * Checks if the specified name matches the entry's name, and if yes,
  * returns the comment value;
  */
-static const char *
-flac_comment_value(const FLAC__StreamMetadata_VorbisComment_Entry *entry,
-		   const char *name) noexcept
+static StringView
+GetFlacCommentValue(const FLAC__StreamMetadata_VorbisComment_Entry *entry,
+		    StringView name) noexcept
 {
-	return vorbis_comment_value((const char *)entry->entry, name);
+	return GetVorbisCommentValue({(const char *)entry->entry, entry->length},
+				     name);
 }
 
 /**
@@ -81,11 +82,11 @@ flac_comment_value(const FLAC__StreamMetadata_VorbisComment_Entry *entry,
  */
 static bool
 flac_copy_comment(const FLAC__StreamMetadata_VorbisComment_Entry *entry,
-		  const char *name, TagType tag_type,
+		  StringView name, TagType tag_type,
 		  TagHandler &handler) noexcept
 {
-	const char *value = flac_comment_value(entry, name);
-	if (value != nullptr) {
+	const auto value = GetFlacCommentValue(entry, name);
+	if (!value.IsNull()) {
 		handler.OnTag(tag_type, value);
 		return true;
 	}

src/lib/xiph/VorbisComments.cxx

@@ -50,14 +50,12 @@ vorbis_comments_to_replay_gain(ReplayGainInfo &rgi, char **comments) noexcept
  * the comment value into the tag.
  */
 static bool
-vorbis_copy_comment(const char *comment,
-		    const char *name, TagType tag_type,
+vorbis_copy_comment(StringView comment,
+		    StringView name, TagType tag_type,
 		    TagHandler &handler) noexcept
 {
-	const char *value;
-
-	value = vorbis_comment_value(comment, name);
-	if (value != nullptr) {
+	const auto value = GetVorbisCommentValue(comment, name);
+	if (!value.IsNull()) {
 		handler.OnTag(tag_type, value);
 		return true;
 	}

src/tag/MixRamp.cxx

@@ -72,8 +72,8 @@ ParseMixRampVorbis(MixRampInfo &info, const char *entry)
 		const char *entry;
 
 		gcc_pure
-		StringView operator[](const char *n) const noexcept {
-			return vorbis_comment_value(entry, n);
+		StringView operator[](StringView n) const noexcept {
+			return GetVorbisCommentValue(entry, n);
 		}
 	};
 

src/tag/ReplayGain.cxx

@@ -70,14 +70,14 @@ ParseReplayGainTag(ReplayGainInfo &info, const char *name, const char *value)
 }
 
 bool
-ParseReplayGainVorbis(ReplayGainInfo &info, const char *entry)
+ParseReplayGainVorbis(ReplayGainInfo &info, StringView entry)
 {
 	struct VorbisCommentEntry {
-		const char *entry;
+		StringView entry;
 
 		gcc_pure
-		const char *operator[](const char *n) const noexcept {
-			return vorbis_comment_value(entry, n);
+		const char *operator[](StringView n) const noexcept {
+			return GetVorbisCommentValue(entry, n).data;
 		}
 	};
 

src/tag/ReplayGain.hxx

@@ -20,12 +20,13 @@
 #ifndef MPD_TAG_REPLAY_GAIN_HXX
 #define MPD_TAG_REPLAY_GAIN_HXX
 
+struct StringView;
 struct ReplayGainInfo;
 
 bool
 ParseReplayGainTag(ReplayGainInfo &info, const char *name, const char *value);
 
 bool
-ParseReplayGainVorbis(ReplayGainInfo &info, const char *entry);
+ParseReplayGainVorbis(ReplayGainInfo &info, StringView entry);
 
 #endif

src/tag/VorbisComment.cxx

@@ -18,23 +18,21 @@
  */
 
 #include "VorbisComment.hxx"
-#include "util/ASCII.hxx"
+#include "util/StringView.hxx"
 
 #include <assert.h>
-#include <string.h>
 
-const char *
-vorbis_comment_value(const char *entry, const char *name) noexcept
+StringView
+GetVorbisCommentValue(StringView entry, StringView name) noexcept
 {
-	assert(entry != nullptr);
-	assert(name != nullptr);
-	assert(*name != 0);
+	assert(!name.empty());
 
-	const size_t length = strlen(name);
-
-	if (StringEqualsCaseASCII(entry, name, length) &&
-	    entry[length] == '=')
-		return entry + length + 1;
+	if (entry.StartsWithIgnoreCase(name) &&
+	    entry.size > name.size &&
+	    entry[name.size] == '=') {
+		entry.skip_front(name.size + 1);
+		return entry;
+	}
 
 	return nullptr;
 }

src/tag/VorbisComment.hxx

@@ -22,12 +22,14 @@
 
 #include "util/Compiler.h"
 
+struct StringView;
+
 /**
  * Checks if the specified name matches the entry's name, and if yes,
  * returns the comment value.
  */
 gcc_pure
-const char *
-vorbis_comment_value(const char *entry, const char *name) noexcept;
+StringView
+GetVorbisCommentValue(StringView entry, StringView name) noexcept;
 
 #endif