new filter option: "badfilter" (see uBlockOrigin/uAssets#192)

src/js/cosmetic-filtering.js

@@ -1148,10 +1148,11 @@ FilterContainer.prototype.fromCompiledContent = function(lineIter, skipGenericCo
         fieldIter = new µb.FieldIterator('\v');
 
     while ( lineIter.eot() === false ) {
-        if ( lineIter.text.charCodeAt(lineIter.offset) !== 0x63 /* 'c' */ ) {
+        line = lineIter.next();
+        if ( line.charCodeAt(0) !== 0x63 /* 'c' */ ) {
+            lineIter.rewind();
             return;
         }
-        line = lineIter.next();
 
         this.acceptedCount += 1;
         if ( this.duplicateBuster.has(line) ) {
@@ -1274,10 +1275,11 @@ FilterContainer.prototype.skipGenericCompiledContent = function(lineIter) {
         fieldIter = new µb.FieldIterator('\v');
 
     while ( lineIter.eot() === false ) {
-        if ( lineIter.text.charCodeAt(lineIter.offset) !== 0x63 /* 'c' */ ) {
+        line = lineIter.next();
+        if ( line.charCodeAt(0) !== 0x63 /* 'c' */ ) {
+            lineIter.rewind();
             return;
         }
-        line = lineIter.next();
 
         this.acceptedCount += 1;
         if ( this.duplicateBuster.has(line) ) {
@@ -1336,10 +1338,11 @@ FilterContainer.prototype.skipCompiledContent = function(lineIter) {
         fieldIter = new µb.FieldIterator('\v');
 
     while ( lineIter.eot() === false ) {
-        if ( lineIter.text.charCodeAt(lineIter.offset) !== 0x63 /* 'c' */ ) {
+        line = lineIter.next();
+        if ( line.charCodeAt(0) !== 0x63 /* 'c' */ ) {
+            lineIter.rewind();
             return;
         }
-        line = lineIter.next();
 
         this.acceptedCount += 1;
         if ( this.duplicateBuster.has(line) ) {

src/js/static-net-filtering.js

@@ -1078,6 +1078,17 @@ FilterBucket.prototype.add = function(a) {
     this.filters.push(a);
 };
 
+FilterBucket.prototype.remove = function(fclass, fdata) {
+    var i = this.filters.length,
+        filter;
+    while ( i-- ) {
+        filter = this.filters[i];
+        if ( filter.fid === fclass && filter.toSelfie() === fdata ) {
+            this.filters.splice(i, 1);
+        }
+    }
+};
+
 // Promote hit filters so they can be found faster next time.
 FilterBucket.prototype.promote = function(i) {
     var filters = this.filters;
@@ -1181,6 +1192,7 @@ FilterParser.prototype.toNormalizedType = {
 FilterParser.prototype.reset = function() {
     this.action = BlockAction;
     this.anchor = 0;
+    this.badFilter = false;
     this.elemHiding = false;
     this.f = '';
     this.firstParty = false;
@@ -1334,6 +1346,11 @@ FilterParser.prototype.parseOptions = function(s) {
         if ( opt === 'empty' ) {
             continue;
         }
+        // https://github.com/uBlockOrigin/uAssets/issues/192
+        if ( opt === 'badfilter' ) {
+            this.badFilter = true;
+            continue;
+        }
         // Unrecognized filter option: ignore whole filter.
         this.unsupported = true;
         break;
@@ -1598,10 +1615,10 @@ FilterContainer.prototype.reset = function() {
     this.allowFilterCount = 0;
     this.blockFilterCount = 0;
     this.discardedCount = 0;
+    this.badFilters = new Set();
     this.duplicateBuster = new Set();
     this.categories = new Map();
     this.filterParser.reset();
-    this.filterCounts = {};
 
     // Reuse filter instances whenever possible at load time.
     this.fclassLast = null;
@@ -1618,6 +1635,7 @@ FilterContainer.prototype.reset = function() {
 
 FilterContainer.prototype.freeze = function() {
     histogram('allFilters', this.categories);
+    this.removeBadFilters();
     this.duplicateBuster = new Set();
     this.filterParser.reset();
     this.fclassLast = null;
@@ -1853,7 +1871,7 @@ FilterContainer.prototype.compile = function(raw, out) {
         return false;
     }
 
-    // Pure hostnames, use more efficient liquid dict
+    // Pure hostnames, use more efficient dictionary lookup
     // https://github.com/chrisaljoudi/uBlock/issues/665
     // Create a dict keyed on request type etc.
     if ( parsed.hostnamePure && this.compileHostnameOnlyFilter(parsed, out) ) {
@@ -1880,16 +1898,19 @@ FilterContainer.prototype.compileHostnameOnlyFilter = function(parsed, out) {
     //    return;
     //}
 
-    var party = AnyParty;
-    if ( parsed.firstParty !== parsed.thirdParty ) {
+    var route = parsed.badFilter ? 'n-\v' : 'n\v',
+        party;
+    if ( parsed.firstParty === parsed.thirdParty ) {
+        party = AnyParty;
+    } else {
         party = parsed.firstParty ? FirstParty : ThirdParty;
     }
     var keyShard = parsed.action | parsed.important | party;
 
     var type = parsed.types;
     if ( type === 0 ) {
         out.push(
-            'n\v' +
+            route +
             toHex(keyShard) + '\v' +
             '.\v' +
             parsed.f
@@ -1901,7 +1922,7 @@ FilterContainer.prototype.compileHostnameOnlyFilter = function(parsed, out) {
     do {
         if ( type & 1 ) {
             out.push(
-                'n\v' +
+                route +
                 toHex(keyShard | (bitOffset << 4)) + '\v' +
                 '.\v' +
                 parsed.f
@@ -1934,11 +1955,12 @@ FilterContainer.prototype.compileFilter = function(parsed, out) {
 /******************************************************************************/
 
 FilterContainer.prototype.compileToAtomicFilter = function(filterClass, parsed, party, out) {
-    var bits = parsed.action | parsed.important | party;
-    var type = parsed.types;
+    var route = parsed.badFilter ? 'n-\v' : 'n\v',
+        bits = parsed.action | parsed.important | party,
+        type = parsed.types;
     if ( type === 0 ) {
         out.push(
-            'n\v' +
+            route +
             toHex(bits) + '\v' +
             parsed.token + '\v' +
             filterClass.fid + '\v' +
@@ -1950,7 +1972,7 @@ FilterContainer.prototype.compileToAtomicFilter = function(filterClass, parsed,
     do {
         if ( type & 1 ) {
             out.push(
-                'n\v' +
+                route +
                 toHex(bits | (bitOffset << 4)) + '\v' +
                 parsed.token + '\v' +
                 filterClass.fid + '\v' +
@@ -1967,6 +1989,10 @@ FilterContainer.prototype.compileToAtomicFilter = function(filterClass, parsed,
         return;
     }
 
+    if ( parsed.badFilter ) {
+        return;
+    }
+
     var redirects = µb.redirectEngine.compileRuleFromStaticFilter(parsed.raw);
     if ( Array.isArray(redirects) === false ) {
         return;
@@ -1985,12 +2011,17 @@ FilterContainer.prototype.fromCompiledContent = function(lineIter) {
         fieldIter = new µb.FieldIterator('\v');
 
     while ( lineIter.eot() === false ) {
-        if ( lineIter.text.charCodeAt(lineIter.offset) !== 0x6E /* 'n' */ ) {
+        line = lineIter.next();
+        if ( line.charCodeAt(0) !== 0x6E /* 'n' */ ) {
+            lineIter.rewind();
             return;
         }
-        line = lineIter.next();
 
-        fieldIter.first(line);
+        if ( fieldIter.first(line) === 'n-' ) {
+            this.badFilters.add(line);
+            continue;
+        }
+
         hash = fieldIter.next();
         token = fieldIter.next();
         fclass = fieldIter.next();
@@ -2046,6 +2077,47 @@ FilterContainer.prototype.fromCompiledContent = function(lineIter) {
 
 /******************************************************************************/
 
+FilterContainer.prototype.removeBadFilters = function() {
+    var lines = µb.setToArray(this.badFilters),
+        fieldIter = new µb.FieldIterator('\v'),
+        hash, token, fclass, fdata, bucket, entry,
+        i = lines.length;
+    while ( i-- ) {
+        fieldIter.first(lines[i]);
+        hash = fieldIter.next();
+        token = fieldIter.next();
+        fclass = fieldIter.next();
+        fdata = fieldIter.next();
+        bucket = this.categories.get(hash);
+        if ( bucket === undefined ) {
+            continue;
+        }
+        entry = bucket.get(token);
+        if ( entry === undefined ) {
+            continue;
+        }
+        if ( entry instanceof FilterHostnameDict ) {
+            entry.delete(fclass);  // 'fclass' is hostname
+            if ( entry.dict.size === 0 ) {
+                this.categories.delete(hash);
+            }
+            continue;
+        }
+        if ( entry instanceof FilterBucket ) {
+            entry.remove(fclass, fdata);
+            if ( entry.filters.length === 1 ) {
+                bucket.set(token, entry.filters[0]);
+            }
+            continue;
+        }
+        if ( entry.fid === fclass && entry.toSelfie() === fdata ) {
+            this.categories.delete(hash);
+        }
+    }
+};
+
+/******************************************************************************/
+
 FilterContainer.prototype.filterStringFromCompiled = function(compiled) {
     var opts = [];
     var vfields = compiled.split('\v');

src/js/utils.js

@@ -163,6 +163,20 @@
     return line;
 };
 
+µBlock.LineIterator.prototype.rewind = function() {
+    if ( this.offset <= 1 ) {
+        this.offset = 0;
+        return;
+    }
+    var lineEnd = this.text.lastIndexOf('\n', this.offset - 2);
+    if ( lineEnd !== -1 ) {
+        this.offset = lineEnd + 1;
+    } else {
+        lineEnd = this.text.lastIndexOf('\r', this.offset - 2);
+        this.offset = lineEnd !== -1 ? lineEnd + 1 : 0;
+    }
+};
+
 µBlock.LineIterator.prototype.eot = function() {
     return this.offset >= this.textLen;
 };
@@ -197,33 +211,37 @@
 
 /******************************************************************************/
 
-µBlock.mapToArray = function(map) {
-    var out = [],
-        entries = map.entries(),
-        entry;
-    for (;;) {
-        entry = entries.next();
-        if ( entry.done ) { break; }
-        out.push([ entry.value[0], entry.value[1] ]);
-    }
-    return out;
-};
+µBlock.mapToArray = typeof Array.from === 'function'
+    ? Array.from
+    : function(map) {
+        var out = [],
+            entries = map.entries(),
+            entry;
+        for (;;) {
+            entry = entries.next();
+            if ( entry.done ) { break; }
+            out.push([ entry.value[0], entry.value[1] ]);
+        }
+        return out;
+    };
 
 µBlock.mapFromArray = function(arr) {
     return new Map(arr);
 };
 
-µBlock.setToArray = function(dict) {
-    var out = [],
-        entries = dict.values(),
-        entry;
-    for (;;) {
-        entry = entries.next();
-        if ( entry.done ) { break; }
-        out.push(entry.value);
-    }
-    return out;
-};
+µBlock.setToArray = typeof Array.from === 'function'
+    ? Array.from
+    : function(dict) {
+        var out = [],
+            entries = dict.values(),
+            entry;
+        for (;;) {
+            entry = entries.next();
+            if ( entry.done ) { break; }
+            out.push(entry.value);
+        }
+        return out;
+    };
 
 µBlock.setFromArray = function(arr) {
     return new Set(arr);