Remove unused code for creating / removing directories and

for recursive directory traversal.

2 files changed, 40 insertions, 290 deletions

diff --git a/searchlib/src/vespa/searchlib/util/dirtraverse.cpp b/searchlib/src/vespa/searchlib/util/dirtraverse.cpp
index 07dbc9a247d..c1e8b6b7396 100644
--- a/searchlib/src/vespa/searchlib/util/dirtraverse.cpp
+++ b/searchlib/src/vespa/searchlib/util/dirtraverse.cpp
@@ -2,275 +2,63 @@
 
 #include "dirtraverse.h"
 #include <vespa/vespalib/util/size_literals.h>
-#include <vespa/fastos/file.h>
-#include <cassert>
-#include <cstring>
+#include <filesystem>
+#include <system_error>
 
 namespace search {
 
-extern "C" {
-static int cmpname(const void *av, const void *bv)
-{
-    const DirectoryTraverse::Name *const a =
-        *(const DirectoryTraverse::Name *const *) av;
-    const DirectoryTraverse::Name *const b =
-        *(const DirectoryTraverse::Name *const *) bv;
-    return a->_name.compare(b->_name.c_str());
-}
-}
-
-DirectoryTraverse::Name::Name(const char *name)
-    : _name(name),
-      _next(nullptr)
-{
-}
-DirectoryTraverse::Name::~Name() = default;
-
-DirectoryTraverse::Name *
-DirectoryTraverse::Name::sort(Name *head, int count)
-{
-    Name *nl;
-    Name **names;
-    int i;
-
-    names = new Name *[count];
-    i = 0;
-    for(nl = head; nl != nullptr; nl = nl->_next)
-        names[i++] = nl;
-    assert(i == count);
-    qsort(names, count, sizeof(Name *), cmpname);
-    for (i = 0; i < count; i++) {
-        if (i + 1 < count)
-            names[i]->_next = names[i + 1];
-        else
-            names[i]->_next = nullptr;
-    }
-    head = names[0];
-    delete [] names;
-    return head;
-}
-
-
-void
-DirectoryTraverse::QueueDir(const char *name)
-{
-    Name *n = new Name(name);
-    if (_dirTail == nullptr)
-        _dirHead = n;
-    else
-        _dirTail->_next = n;
-    _dirTail = n;
-}
+namespace fs = std::filesystem;
 
+namespace {
 
-void
-DirectoryTraverse::PushDir(const char *name)
-{
-    Name *n = new Name(name);
-    n->_next = _pdirHead;
-    _pdirHead = n;
-}
-
-
-void
-DirectoryTraverse::PushRemoveDir(const char *name)
-{
-    Name *n = new Name(name);
-    n->_next = _rdirHead;
-    _rdirHead = n;
-}
-
-
-void
-DirectoryTraverse::PushPushedDirs()
-{
-    Name *n;
-    while (_pdirHead != nullptr) {
-        n = _pdirHead;
-        _pdirHead = n->_next;
-        n->_next = _dirHead;
-        _dirHead = n;
-        if (_dirTail == nullptr)
-            _dirTail = n;
-    }
-}
-
-
-DirectoryTraverse::Name *
-DirectoryTraverse::UnQueueDir()
-{
-    Name *n;
-    PushPushedDirs();
-    if (_dirHead == nullptr)
-        return nullptr;
-    n = _dirHead;
-    _dirHead = n->_next;
-    n->_next = nullptr;
-    if (_dirHead == nullptr)
-        _dirTail = nullptr;
-    return n;
-}
-
-DirectoryTraverse::Name *
-DirectoryTraverse::UnQueueName()
-{
-    Name *n;
-    if (_nameHead == nullptr)
-        return nullptr;
-    n = _nameHead;
-    _nameHead = n->_next;
-    n->_next = nullptr;
-    _nameCount--;
-    return n;
-}
-
-
-void
-DirectoryTraverse::ScanSingleDir()
+uint64_t
+try_get_tree_size(const std::string& base_dir)
 {
-    assert(_nameHead == nullptr);
-    assert(_nameCount == 0);
-    delete _curDir;
-    _fullDirName.clear();
-    _curDir = UnQueueDir();
-    if (_curDir == nullptr)
-        return;
-    _fullDirName = _baseDir;
-    if ( ! _curDir->_name.empty()) {
-        _fullDirName += "/" + _curDir->_name;
+    fs::path path(base_dir);
+    std::error_code ec;
+    fs::recursive_directory_iterator dir_itr(path, fs::directory_options::skip_permission_denied, ec);
+    if (ec) {
+        return 0;
     }
-    FastOS_DirectoryScan *dirscan = new FastOS_DirectoryScan(_fullDirName.c_str());
-    while (dirscan->ReadNext()) {
-        const char *name = dirscan->GetName();
-        if (strcmp(name, ".") == 0 ||
-            strcmp(name, "..") == 0)
-            continue;
-        Name *nl = new Name(name);
-        nl->_next = _nameHead;
-        _nameHead = nl;
-        _nameCount++;
-    }
-    if (_nameCount > 1)
-        _nameHead = _nameHead->sort(_nameHead, _nameCount);
-    delete dirscan;
-}
-
-
-bool
-DirectoryTraverse::NextName()
-{
-    delete _curName;
-    _curName = nullptr;
-    while (_nameHead == nullptr && (_dirHead != nullptr || _pdirHead != nullptr))
-        ScanSingleDir();
-    if (_nameHead == nullptr)
-        return false;
-    _curName = UnQueueName();
-    _fullName = _fullDirName + "/" + _curName->_name;
-    _relName = _fullName.c_str() + (_baseDir.size() + 1);
-    return true;
-}
-
-
-bool
-DirectoryTraverse::NextRemoveDir()
-{
-    Name *curName;
 
-    delete _curName;
-    _curName = nullptr;
-    if (_rdirHead == nullptr)
-        return false;
-    curName = _rdirHead;
-    _rdirHead = curName->_next;
-    _fullName = _baseDir + "/" + curName->_name;
-    _relName = _fullName.c_str() + _baseDir.size() + 1;
-    delete curName;
-    return true;
-}
-
-
-bool
-DirectoryTraverse::RemoveTree()
-{
-    FastOS_StatInfo statInfo;
-
-    while (NextName()) {
-        const char *relname = GetRelName();
-        const char *fullname = GetFullName();
-        if (FastOS_File::Stat(fullname, &statInfo)) {
-            if (statInfo._isDirectory) {
-                PushDir(relname);
-                PushRemoveDir(relname);
-            } else {
-                FastOS_File::Delete(fullname);
+    uint64_t total_size = 0;
+    constexpr uint64_t block_size = 4_Ki;
+    for (const auto &elem : dir_itr) {
+        if (fs::is_regular_file(elem.path()) && !fs::is_symlink(elem.path())) {
+            const auto size = elem.file_size(ec);
+            if (!ec) {
+                // round up size to file system block size (assumed to be 4 KiB)
+                auto adj_size = ((size + block_size - 1) / block_size) * block_size;
+                total_size += adj_size;
             }
         }
     }
-    while (NextRemoveDir()) {
-        const char *fullname = GetFullName();
-        FastOS_File::RemoveDirectory(fullname);
-    }
-    FastOS_File::RemoveDirectory(_baseDir.c_str());
-    return true;
+    return total_size;
+}
+
 }
 
 uint64_t
 DirectoryTraverse::GetTreeSize()
 {
-    FastOS_StatInfo statInfo;
-    uint64_t size = 0;
-    const uint64_t blockSize = 4_Ki;
-
-    while (NextName()) {
-        const char *relname = GetRelName();
-        const char *fullname = GetFullName();
-        if (FastOS_File::Stat(fullname, &statInfo)) {
-            uint64_t adjSize = ((statInfo._size + blockSize - 1) / blockSize) * blockSize;
-            size += adjSize;
-            if (statInfo._isDirectory) {
-                PushDir(relname);
-            }
+    // Since try_get_tree_size may throw on concurrent directory
+    // modifications, immediately retry a bounded number of times if this
+    // happens.  Number of retries chosen randomly by counting fingers.
+    for (int i = 0; i < 10; ++i) {
+        try {
+            return try_get_tree_size(_base_dir);
+        } catch (const fs::filesystem_error&) {
+            // Go around for another spin that hopefully won't race.
         }
     }
-    return size;
+    return 0;
 }
 
-DirectoryTraverse::DirectoryTraverse(const char *baseDir)
-    : _baseDir(baseDir),
-      _nameHead(nullptr),
-      _nameCount(0),
-      _dirHead(nullptr),
-      _dirTail(nullptr),
-      _pdirHead(nullptr),
-      _rdirHead(nullptr),
-      _curDir(nullptr),
-      _curName(nullptr),
-      _fullDirName(),
-      _fullName(),
-      _relName(nullptr)
+DirectoryTraverse::DirectoryTraverse(const std::string& base_dir)
+    : _base_dir(base_dir)
 {
-    QueueDir("");
-    ScanSingleDir();
 }
 
-
-DirectoryTraverse::~DirectoryTraverse()
-{
-    delete _curDir;
-    delete _curName;
-    PushPushedDirs();
-    while (_dirHead != nullptr)
-        delete UnQueueDir();
-    while (_nameHead != nullptr)
-        delete UnQueueName();
-    while (_rdirHead != nullptr) {
-        Name *n;
-        n = _rdirHead;
-        _rdirHead = n->_next;
-        n->_next = nullptr;
-        delete n;
-    }
-}
+DirectoryTraverse::~DirectoryTraverse() = default;
 
 } // namespace search
diff --git a/searchlib/src/vespa/searchlib/util/dirtraverse.h b/searchlib/src/vespa/searchlib/util/dirtraverse.h
index 4a96ad0935d..c26246e2596 100644
--- a/searchlib/src/vespa/searchlib/util/dirtraverse.h
+++ b/searchlib/src/vespa/searchlib/util/dirtraverse.h
@@ -7,54 +7,16 @@
 
 namespace search {
 
+/*
+ * Class used to get size of directory tree on disk.
+ */
 class DirectoryTraverse
 {
 private:
-    DirectoryTraverse(const DirectoryTraverse &);
-    DirectoryTraverse& operator=(const DirectoryTraverse &);
-
-public:
-    class Name
-    {
-    private:
-        Name(const Name &);
-        Name& operator=(const Name &);
-
-    public:
-        std::string _name;
-        Name *_next;
-        explicit Name(const char *name);
-        ~Name();
-        static Name *sort(Name *head, int count);
-    };
-private:
-    std::string _baseDir;
-    Name *_nameHead;
-    int _nameCount;
-    Name *_dirHead;
-    Name *_dirTail;
-    Name *_pdirHead;
-    Name *_rdirHead;
-    Name *_curDir;
-    Name *_curName;
-    std::string _fullDirName;
-    std::string _fullName;
-    const char *_relName;
+    std::string _base_dir;
 public:
-    const char *GetFullName() const { return _fullName.c_str(); }
-    const char *GetRelName() const { return _relName; }
-    void QueueDir(const char *name);
-    void PushDir(const char *name);
-    void PushRemoveDir(const char *name);
-    void PushPushedDirs();
-    Name *UnQueueDir();
-    Name *UnQueueName();
-    void ScanSingleDir();
-    bool NextName();
-    bool NextRemoveDir();
-    bool RemoveTree();
     uint64_t GetTreeSize(); // Returns size of directory in bytes
-    explicit DirectoryTraverse(const char *baseDir);
+    explicit DirectoryTraverse(const std::string& base_dir);
     ~DirectoryTraverse();
 };