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-rw-r--r--src/3rdparty/libpsl/src/lookup_string_in_fixed_set.c273
1 files changed, 273 insertions, 0 deletions
diff --git a/src/3rdparty/libpsl/src/lookup_string_in_fixed_set.c b/src/3rdparty/libpsl/src/lookup_string_in_fixed_set.c
new file mode 100644
index 0000000000..57c2e4ea12
--- /dev/null
+++ b/src/3rdparty/libpsl/src/lookup_string_in_fixed_set.c
@@ -0,0 +1,273 @@
+/* Copyright 2015-2016 The Chromium Authors. All rights reserved.
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE.chromium file.
+ *
+ * Converted to C89 2015 by Tim Rühsen
+ */
+
+#include <stddef.h>
+
+#define CHECK_LT(a, b) if ((a) >= b) return 0
+
+static const char multibyte_length_table[16] = {
+ 0, 0, 0, 0, /* 0x00-0x3F */
+ 0, 0, 0, 0, /* 0x40-0x7F */
+ 0, 0, 0, 0, /* 0x80-0xBF */
+ 2, 2, 3, 4, /* 0xC0-0xFF */
+};
+
+
+/*
+ * Get length of multibyte character sequence starting at a given byte.
+ * Returns zero if the byte is not a valid leading byte in UTF-8.
+ */
+static int GetMultibyteLength(char c) {
+ return multibyte_length_table[((unsigned char)c) >> 4];
+}
+
+/*
+ * Moves pointers one byte forward.
+ */
+static void NextPos(const unsigned char** pos,
+ const char** key,
+ const char** multibyte_start)
+{
+ ++*pos;
+ if (*multibyte_start) {
+ /* Advance key to next byte in multibyte sequence. */
+ ++*key;
+ /* Reset multibyte_start if last byte in multibyte sequence was consumed. */
+ if (*key - *multibyte_start == GetMultibyteLength(**multibyte_start))
+ *multibyte_start = 0;
+ } else {
+ if (GetMultibyteLength(**key)) {
+ /* Multibyte prefix was matched in the dafsa, start matching multibyte
+ * content in next round. */
+ *multibyte_start = *key;
+ } else {
+ /* Advance key as a single byte character was matched. */
+ ++*key;
+ }
+ }
+}
+
+/*
+ * Read next offset from pos.
+ * Returns true if an offset could be read, false otherwise.
+ */
+
+static int GetNextOffset(const unsigned char** pos,
+ const unsigned char* end,
+ const unsigned char** offset)
+{
+ size_t bytes_consumed;
+
+ if (*pos == end)
+ return 0;
+
+ /* When reading an offset the byte array must always contain at least
+ * three more bytes to consume. First the offset to read, then a node
+ * to skip over and finally a destination node. No object can be smaller
+ * than one byte. */
+ CHECK_LT(*pos + 2, end);
+ switch (**pos & 0x60) {
+ case 0x60: /* Read three byte offset */
+ *offset += (((*pos)[0] & 0x1F) << 16) | ((*pos)[1] << 8) | (*pos)[2];
+ bytes_consumed = 3;
+ break;
+ case 0x40: /* Read two byte offset */
+ *offset += (((*pos)[0] & 0x1F) << 8) | (*pos)[1];
+ bytes_consumed = 2;
+ break;
+ default:
+ *offset += (*pos)[0] & 0x3F;
+ bytes_consumed = 1;
+ }
+ if ((**pos & 0x80) != 0) {
+ *pos = end;
+ } else {
+ *pos += bytes_consumed;
+ }
+ return 1;
+}
+
+/*
+ * Check if byte at offset is last in label.
+ */
+
+static int IsEOL(const unsigned char* offset, const unsigned char* end)
+{
+ CHECK_LT(offset, end);
+ return(*offset & 0x80) != 0;
+}
+
+/*
+ * Check if byte at offset matches first character in key.
+ * This version assumes a range check was already performed by the caller.
+ */
+
+static int IsMatchUnchecked(const unsigned char matcher,
+ const char* key,
+ const char* multibyte_start)
+{
+ if (multibyte_start) {
+ /* Multibyte matching mode. */
+ if (multibyte_start == key) {
+ /* Match leading byte, which will also match the sequence length. */
+ return (matcher ^ 0x80) == (const unsigned char)*key;
+ } else {
+ /* Match following bytes. */
+ return (matcher ^ 0xC0) == (const unsigned char)*key;
+ }
+ }
+ /* If key points at a leading byte in a multibyte sequence, but we are not yet
+ * in multibyte mode, then the dafsa should contain a special byte to indicate
+ * a mode switch. */
+ if (GetMultibyteLength(*key)) {
+ return matcher == 0x1F;
+ }
+ /* Normal matching of a single byte character. */
+ return matcher == (const unsigned char)*key;
+}
+
+/*
+ * Check if byte at offset matches first character in key.
+ * This version matches characters not last in label.
+ */
+
+static int IsMatch(const unsigned char* offset,
+ const unsigned char* end,
+ const char* key,
+ const char* multibyte_start)
+{
+ CHECK_LT(offset, end);
+ return IsMatchUnchecked(*offset, key, multibyte_start);
+}
+
+/*
+ * Check if byte at offset matches first character in key.
+ * This version matches characters last in label.
+ */
+
+static int IsEndCharMatch(const unsigned char* offset,
+ const unsigned char* end,
+ const char* key,
+ const char* multibyte_start)
+{
+ CHECK_LT(offset, end);
+ return IsMatchUnchecked(*offset ^ 0x80, key, multibyte_start);
+}
+
+/*
+ * Read return value at offset.
+ * Returns true if a return value could be read, false otherwise.
+ */
+
+static int GetReturnValue(const unsigned char* offset,
+ const unsigned char* end,
+ const char* multibyte_start,
+ int* return_value)
+{
+ CHECK_LT(offset, end);
+ if (!multibyte_start && (*offset & 0xE0) == 0x80) {
+ *return_value = *offset & 0x0F;
+ return 1;
+ }
+ return 0;
+}
+
+/*
+ * Looks up the string |key| with length |key_length| in a fixed set of
+ * strings. The set of strings must be known at compile time. It is converted to
+ * a graph structure named a DAFSA (Deterministic Acyclic Finite State
+ * Automaton) by the script psl-make-dafsa during compilation. This permits
+ * efficient (in time and space) lookup. The graph generated by psl-make-dafsa
+ * takes the form of a constant byte array which should be supplied via the
+ * |graph| and |length| parameters. The return value is kDafsaNotFound,
+ * kDafsaFound, or a bitmap consisting of one or more of kDafsaExceptionRule,
+ * kDafsaWildcardRule and kDafsaPrivateRule ORed together.
+ *
+ * Lookup a domain key in a byte array generated by psl-make-dafsa.
+ */
+
+/* prototype to skip warning with -Wmissing-prototypes */
+int LookupStringInFixedSet(const unsigned char*, size_t,const char*, size_t);
+
+int LookupStringInFixedSet(const unsigned char* graph,
+ size_t length,
+ const char* key,
+ size_t key_length)
+{
+ const unsigned char* pos = graph;
+ const unsigned char* end = graph + length;
+ const unsigned char* offset = pos;
+ const char* key_end = key + key_length;
+ const char* multibyte_start = 0;
+
+ while (GetNextOffset(&pos, end, &offset)) {
+ /*char <char>+ end_char offsets
+ * char <char>+ return value
+ * char end_char offsets
+ * char return value
+ * end_char offsets
+ * return_value
+ */
+ int did_consume = 0;
+
+ if (key != key_end && !IsEOL(offset, end)) {
+ /* Leading <char> is not a match. Don't dive into this child */
+ if (!IsMatch(offset, end, key, multibyte_start))
+ continue;
+ did_consume = 1;
+ NextPos(&offset, &key, &multibyte_start);
+ /* Possible matches at this point:
+ * <char>+ end_char offsets
+ * <char>+ return value
+ * end_char offsets
+ * return value
+ */
+
+ /* Remove all remaining <char> nodes possible */
+ while (!IsEOL(offset, end) && key != key_end) {
+ if (!IsMatch(offset, end, key, multibyte_start))
+ return -1;
+ NextPos(&offset, &key, &multibyte_start);
+ }
+ }
+ /* Possible matches at this point:
+ * end_char offsets
+ * return_value
+ * If one or more <char> elements were consumed, a failure
+ * to match is terminal. Otherwise, try the next node.
+ */
+ if (key == key_end) {
+ int return_value;
+
+ if (GetReturnValue(offset, end, multibyte_start, &return_value))
+ return return_value;
+ /* The DAFSA guarantees that if the first char is a match, all
+ * remaining char elements MUST match if the key is truly present.
+ */
+ if (did_consume)
+ return -1;
+ continue;
+ }
+ if (!IsEndCharMatch(offset, end, key, multibyte_start)) {
+ if (did_consume)
+ return -1; /* Unexpected */
+ continue;
+ }
+ NextPos(&offset, &key, &multibyte_start);
+ pos = offset; /* Dive into child */
+ }
+
+ return -1; /* No match */
+}
+
+/* prototype to skip warning with -Wmissing-prototypes */
+int GetUtfMode(const unsigned char *graph, size_t length);
+
+int GetUtfMode(const unsigned char *graph, size_t length)
+{
+ return length > 0 && graph[length - 1] < 0x80;
+}