Paths.java
/*
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package org.eclipse.jgit.util;
import static org.eclipse.jgit.lib.FileMode.TYPE_MASK;
import static org.eclipse.jgit.lib.FileMode.TYPE_TREE;
/**
* Utility functions for paths inside of a Git repository.
*
* @since 4.2
*/
public class Paths {
/**
* Remove trailing {@code '/'} if present.
*
* @param path
* input path to potentially remove trailing {@code '/'} from.
* @return null if {@code path == null}; {@code path} after removing a
* trailing {@code '/'}.
*/
public static String stripTrailingSeparator(String path) {
if (path == null || path.isEmpty()) {
return path;
}
int i = path.length();
if (path.charAt(path.length() - 1) != '/') {
return path;
}
do {
i--;
} while (path.charAt(i - 1) == '/');
return path.substring(0, i);
}
/**
* Compare two paths according to Git path sort ordering rules.
*
* @param aPath
* first path buffer. The range {@code [aPos, aEnd)} is used.
* @param aPos
* index into {@code aPath} where the first path starts.
* @param aEnd
* 1 past last index of {@code aPath}.
* @param aMode
* mode of the first file. Trees are sorted as though
* {@code aPath[aEnd] == '/'}, even if aEnd does not exist.
* @param bPath
* second path buffer. The range {@code [bPos, bEnd)} is used.
* @param bPos
* index into {@code bPath} where the second path starts.
* @param bEnd
* 1 past last index of {@code bPath}.
* @param bMode
* mode of the second file. Trees are sorted as though
* {@code bPath[bEnd] == '/'}, even if bEnd does not exist.
* @return <0 if {@code aPath} sorts before {@code bPath};
* 0 if the paths are the same;
* >0 if {@code aPath} sorts after {@code bPath}.
*/
public static int compare(byte[] aPath, int aPos, int aEnd, int aMode,
byte[] bPath, int bPos, int bEnd, int bMode) {
int cmp = coreCompare(
aPath, aPos, aEnd, aMode,
bPath, bPos, bEnd, bMode);
if (cmp == 0) {
cmp = lastPathChar(aMode) - lastPathChar(bMode);
}
return cmp;
}
/**
* Compare two paths, checking for identical name.
* <p>
* Unlike {@code compare} this method returns {@code 0} when the paths have
* the same characters in their names, even if the mode differs. It is
* intended for use in validation routines detecting duplicate entries.
* <p>
* Returns {@code 0} if the names are identical and a conflict exists
* between {@code aPath} and {@code bPath}, as they share the same name.
* <p>
* Returns {@code <0} if all possibles occurrences of {@code aPath} sort
* before {@code bPath} and no conflict can happen. In a properly sorted
* tree there are no other occurrences of {@code aPath} and therefore there
* are no duplicate names.
* <p>
* Returns {@code >0} when it is possible for a duplicate occurrence of
* {@code aPath} to appear later, after {@code bPath}. Callers should
* continue to examine candidates for {@code bPath} until the method returns
* one of the other return values.
*
* @param aPath
* first path buffer. The range {@code [aPos, aEnd)} is used.
* @param aPos
* index into {@code aPath} where the first path starts.
* @param aEnd
* 1 past last index of {@code aPath}.
* @param bPath
* second path buffer. The range {@code [bPos, bEnd)} is used.
* @param bPos
* index into {@code bPath} where the second path starts.
* @param bEnd
* 1 past last index of {@code bPath}.
* @param bMode
* mode of the second file. Trees are sorted as though
* {@code bPath[bEnd] == '/'}, even if bEnd does not exist.
* @return <0 if no duplicate name could exist;
* 0 if the paths have the same name;
* >0 other {@code bPath} should still be checked by caller.
*/
public static int compareSameName(
byte[] aPath, int aPos, int aEnd,
byte[] bPath, int bPos, int bEnd, int bMode) {
return coreCompare(
aPath, aPos, aEnd, TYPE_TREE,
bPath, bPos, bEnd, bMode);
}
private static int coreCompare(
byte[] aPath, int aPos, int aEnd, int aMode,
byte[] bPath, int bPos, int bEnd, int bMode) {
while (aPos < aEnd && bPos < bEnd) {
int cmp = (aPath[aPos++] & 0xff) - (bPath[bPos++] & 0xff);
if (cmp != 0) {
return cmp;
}
}
if (aPos < aEnd) {
return (aPath[aPos] & 0xff) - lastPathChar(bMode);
}
if (bPos < bEnd) {
return lastPathChar(aMode) - (bPath[bPos] & 0xff);
}
return 0;
}
private static int lastPathChar(int mode) {
if ((mode & TYPE_MASK) == TYPE_TREE) {
return '/';
}
return 0;
}
private Paths() {
}
}