intermediate changes

ref:cde9a383711a11544ce7e107a78147fb96cc4029

1 files changed, 151 insertions, 0 deletions

diff --git a/util/folder/pathsplit.cpp b/util/folder/pathsplit.cpp
new file mode 100644
index 0000000000..81d439a727
--- /dev/null
+++ b/util/folder/pathsplit.cpp
@@ -0,0 +1,151 @@
+#include "pathsplit.h"
+
+#include "dirut.h"
+
+#include <util/stream/output.h>
+#include <util/generic/yexception.h>
+
+template <class T>
+static inline size_t ToReserve(const T& t) {
+    size_t ret = t.size() + 5;
+
+    for (auto it = t.begin(); it != t.end(); ++it) {
+        ret += it->size();
+    }
+
+    return ret;
+}
+
+void TPathSplitTraitsUnix::DoParseFirstPart(const TStringBuf part) {
+    if (part == TStringBuf(".")) {
+        push_back(TStringBuf("."));
+
+        return;
+    }
+
+    if (IsAbsolutePath(part)) {
+        IsAbsolute = true;
+    }
+
+    DoParsePart(part);
+}
+
+void TPathSplitTraitsUnix::DoParsePart(const TStringBuf part0) {
+    DoAppendHint(part0.size() / 8);
+
+    TStringBuf next(part0);
+    TStringBuf part;
+
+    while (TStringBuf(next).TrySplit('/', part, next)) {
+        AppendComponent(part);
+    }
+
+    AppendComponent(next);
+}
+
+void TPathSplitTraitsWindows::DoParseFirstPart(const TStringBuf part0) {
+    TStringBuf part(part0);
+
+    if (part == TStringBuf(".")) {
+        push_back(TStringBuf("."));
+
+        return;
+    }
+
+    if (IsAbsolutePath(part)) {
+        IsAbsolute = true;
+
+        if (part.size() > 1 && part[1] == ':') {
+            Drive = part.SubStr(0, 2);
+            part = part.SubStr(2);
+        }
+    }
+
+    DoParsePart(part);
+}
+
+void TPathSplitTraitsWindows::DoParsePart(const TStringBuf part0) {
+    DoAppendHint(part0.size() / 8);
+
+    size_t pos = 0;
+    TStringBuf part(part0);
+
+    while (pos < part.size()) {
+        while (pos < part.size() && this->IsPathSep(part[pos])) {
+            ++pos;
+        }
+
+        const char* begin = part.data() + pos;
+
+        while (pos < part.size() && !this->IsPathSep(part[pos])) {
+            ++pos;
+        }
+
+        AppendComponent(TStringBuf(begin, part.data() + pos));
+    }
+}
+
+TString TPathSplitStore::DoReconstruct(const TStringBuf slash) const {
+    TString r;
+
+    r.reserve(ToReserve(*this));
+
+    if (IsAbsolute) {
+        r.AppendNoAlias(Drive);
+        r.AppendNoAlias(slash);
+    }
+
+    for (auto i = begin(); i != end(); ++i) {
+        if (i != begin()) {
+            r.AppendNoAlias(slash);
+        }
+
+        r.AppendNoAlias(*i);
+    }
+
+    return r;
+}
+
+void TPathSplitStore::AppendComponent(const TStringBuf comp) {
+    if (!comp || comp == TStringBuf(".")) {
+        ; // ignore
+    } else if (comp == TStringBuf("..") && !empty() && back() != TStringBuf("..")) {
+        pop_back();
+    } else {
+        // push back first .. also
+        push_back(comp);
+    }
+}
+
+TStringBuf TPathSplitStore::Extension() const {
+    return size() > 0 ? CutExtension(back()) : TStringBuf();
+}
+
+template <>
+void Out<TPathSplit>(IOutputStream& o, const TPathSplit& ps) {
+    o << ps.Reconstruct();
+}
+
+TString JoinPaths(const TPathSplit& p1, const TPathSplit& p2) {
+    if (p2.IsAbsolute) {
+        ythrow yexception() << "can not join " << p1 << " and " << p2;
+    }
+
+    return TPathSplit(p1).AppendMany(p2.begin(), p2.end()).Reconstruct();
+}
+
+TStringBuf CutExtension(const TStringBuf fileName) {
+    if (fileName.empty()) {
+        return fileName;
+    }
+
+    TStringBuf name;
+    TStringBuf extension;
+    fileName.RSplit('.', name, extension);
+    if (name.empty()) {
+        // dot at a start or not found
+        return name;
+    } else {
+        return extension;
+    }
+}