/*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is furnished to do
* so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package jdk.nashorn.internal.runtime.regexp.joni;
@SuppressWarnings("javadoc")
public abstract class SearchAlgorithm {
public abstract String getName();
public abstract int search(Regex regex, char[] text, int textP, int textEnd, int textRange);
public abstract int searchBackward(Regex regex, char[] text, int textP, int adjustText, int textEnd, int textStart, int s_, int range_);
public static final SearchAlgorithm NONE = new SearchAlgorithm() {
@Override
public final String getName() {
return "NONE";
}
@Override
public final int search(final Regex regex, final char[] text, final int textP, final int textEnd, final int textRange) {
return textP;
}
@Override
public final int searchBackward(final Regex regex, final char[] text, final int textP, final int adjustText, final int textEnd, final int textStart, final int s_, final int range_) {
return textP;
}
};
public static final SearchAlgorithm SLOW = new SearchAlgorithm() {
@Override
public final String getName() {
return "EXACT";
}
@Override
public final int search(final Regex regex, final char[] text, final int textP, final int textEnd, final int textRange) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
int end = textEnd;
end -= targetEnd - targetP - 1;
if (end > textRange) {
end = textRange;
}
int s = textP;
while (s < end) {
if (text[s] == target[targetP]) {
int p = s + 1;
int t = targetP + 1;
while (t < targetEnd) {
if (target[t] != text[p++]) {
break;
}
t++;
}
if (t == targetEnd) {
return s;
}
}
s++;
}
return -1;
}
@Override
public final int searchBackward(final Regex regex, final char[] text, final int textP, final int adjustText, final int textEnd, final int textStart, final int s_, final int range_) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
int s = textEnd;
s -= targetEnd - targetP;
if (s > textStart) {
s = textStart;
}
while (s >= textP) {
if (text[s] == target[targetP]) {
int p = s + 1;
int t = targetP + 1;
while (t < targetEnd) {
if (target[t] != text[p++]) {
break;
}
t++;
}
if (t == targetEnd) {
return s;
}
}
// s = enc.prevCharHead or s = s <= adjustText ? -1 : s - 1;
s--;
}
return -1;
}
};
public static final class SLOW_IC extends SearchAlgorithm {
public SLOW_IC(final Regex regex) {
//empty
}
@Override
public final String getName() {
return "EXACT_IC";
}
@Override
public final int search(final Regex regex, final char[] text, final int textP, final int textEnd, final int textRange) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
int end = textEnd;
end -= targetEnd - targetP - 1;
if (end > textRange) {
end = textRange;
}
int s = textP;
while (s < end) {
if (lowerCaseMatch(target, targetP, targetEnd, text, s, textEnd)) {
return s;
}
s++;
}
return -1;
}
@Override
public final int searchBackward(final Regex regex, final char[] text, final int textP, final int adjustText, final int textEnd, final int textStart, final int s_, final int range_) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
int s = textEnd;
s -= targetEnd - targetP;
if (s > textStart) {
s = textStart;
}
while (s >= textP) {
if (lowerCaseMatch(target, targetP, targetEnd, text, s, textEnd)) {
return s;
}
s = EncodingHelper.prevCharHead(adjustText, s);
}
return -1;
}
private static boolean lowerCaseMatch(final char[] t, final int tPp, final int tEnd,
final char[] chars, final int pp, final int end) {
for (int tP = tPp, p = pp; tP < tEnd; ) {
if (t[tP++] != EncodingHelper.toLowerCase(chars[p++])) {
return false;
}
}
return true;
}
}
public static final SearchAlgorithm BM = new SearchAlgorithm() {
@Override
public final String getName() {
return "EXACT_BM";
}
@Override
public final int search(final Regex regex, final char[] text, final int textP, final int textEnd, final int textRange) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
int end = textRange + (targetEnd - targetP) - 1;
if (end > textEnd) {
end = textEnd;
}
final int tail = targetEnd - 1;
int s = textP + (targetEnd - targetP) - 1;
if (regex.intMap == null) {
while (s < end) {
int p = s;
int t = tail;
while (text[p] == target[t]) {
if (t == targetP) {
return p;
}
p--; t--;
}
s += regex.map[text[s] & 0xff];
}
} else { /* see int_map[] */
while (s < end) {
int p = s;
int t = tail;
while (text[p] == target[t]) {
if (t == targetP) {
return p;
}
p--; t--;
}
s += regex.intMap[text[s] & 0xff];
}
}
return -1;
}
private static final int BM_BACKWARD_SEARCH_LENGTH_THRESHOLD = 100;
@Override
public final int searchBackward(final Regex regex, final char[] text, final int textP, final int adjustText, final int textEnd, final int textStart, final int s_, final int range_) {
final char[] target = regex.exact;
final int targetP = regex.exactP;
final int targetEnd = regex.exactEnd;
if (regex.intMapBackward == null) {
if (s_ - range_ < BM_BACKWARD_SEARCH_LENGTH_THRESHOLD) {
// goto exact_method;
return SLOW.searchBackward(regex, text, textP, adjustText, textEnd, textStart, s_, range_);
}
setBmBackwardSkip(regex, target, targetP, targetEnd);
}
int s = textEnd - (targetEnd - targetP);
if (textStart < s) {
s = textStart;
}
while (s >= textP) {
int p = s;
int t = targetP;
while (t < targetEnd && text[p] == target[t]) {
p++; t++;
}
if (t == targetEnd) {
return s;
}
s -= regex.intMapBackward[text[s] & 0xff];
}
return -1;
}
private void setBmBackwardSkip(final Regex regex, final char[] chars, final int p, final int end) {
int[] skip;
if (regex.intMapBackward == null) {
skip = new int[Config.CHAR_TABLE_SIZE];
regex.intMapBackward = skip;
} else {
skip = regex.intMapBackward;
}
final int len = end - p;
for (int i=0; i<Config.CHAR_TABLE_SIZE; i++) {
skip[i] = len;
}
for (int i=len-1; i>0; i--) {
skip[chars[i] & 0xff] = i;
}
}
};
public static final SearchAlgorithm MAP = new SearchAlgorithm() {
@Override
public final String getName() {
return "MAP";
}
@Override
public final int search(final Regex regex, final char[] text, final int textP, final int textEnd, final int textRange) {
final byte[] map = regex.map;
int s = textP;
while (s < textRange) {
if (text[s] > 0xff || map[text[s]] != 0) {
return s;
}
s++;
}
return -1;
}
@Override
public final int searchBackward(final Regex regex, final char[] text, final int textP, final int adjustText, final int textEnd, final int textStart, final int s_, final int range_) {
final byte[] map = regex.map;
int s = textStart;
if (s >= textEnd) {
s = textEnd - 1;
}
while (s >= textP) {
if (text[s] > 0xff || map[text[s]] != 0) {
return s;
}
s--;
}
return -1;
}
};
}