From 3045a5709df597526f474aa0c5a583a76d9921db Mon Sep 17 00:00:00 2001 From: Karen Arutyunov Date: Mon, 2 Mar 2020 23:25:02 +0300 Subject: Backup --- libbutl/filesystem.cxx | 105 +++++++++++++++++++++++++++++++++++++++++--- tests/link/driver.cxx | 43 +++++++++++++----- tests/mventry/testscript | 5 ++- tests/path-entry/driver.cxx | 22 ++++++++-- tests/path-entry/testscript | 9 ++++ 5 files changed, 162 insertions(+), 22 deletions(-) diff --git a/libbutl/filesystem.cxx b/libbutl/filesystem.cxx index 1fec18b..70c8530 100644 --- a/libbutl/filesystem.cxx +++ b/libbutl/filesystem.cxx @@ -33,6 +33,8 @@ # endif #endif +#include // @@ TMP + #include #ifndef __cpp_lib_modules_ts @@ -191,6 +193,67 @@ namespace butl return junction_target_exists (p.string ().c_str (), ignore_error); } + static inline bool + symlink (DWORD a) noexcept + { + return a != INVALID_FILE_ATTRIBUTES && + (a & FILE_ATTRIBUTE_REPARSE_POINT) != 0; + } + + static inline bool + symlink (const path& p) noexcept + { + return symlink (GetFileAttributesA (p.string ().c_str ())); + } + + // @@ TODO + // + static pair + symlink_target_entry (const char* p, bool ignore_error) + { + HANDLE h (CreateFile (p, + FILE_READ_ATTRIBUTES, + FILE_SHARE_READ | FILE_SHARE_WRITE, + NULL, + OPEN_EXISTING, + FILE_FLAG_BACKUP_SEMANTICS, + NULL)); + + if (h == INVALID_HANDLE_VALUE) + { + DWORD ec; + + if (ignore_error || error_file_not_found (ec = GetLastError ())) + return make_pair (false, entry_stat {entry_type::unknown, 0}); + + throw_system_error (ec); + } + + DWORD ec (0); + BY_HANDLE_FILE_INFORMATION fi; + + if (!GetFileInformationByHandle (h, &fi)) + ec = GetLastError (); + + CloseHandle (h); + + if (ec != 0) + { + if (ignore_error) + return make_pair (false, entry_stat {entry_type::unknown, 0}); + + throw_system_error (ec); + } + + if ((fi.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) == 0) + return make_pair (true, + entry_stat {entry_type::regular, + (uint64_t (fi.nFileSizeHigh) << 32) | + fi.nFileSizeLow}); + else + return make_pair (true, entry_stat {entry_type::directory, 0}); + } + pair path_entry (const char* p, bool fl, bool ie) { @@ -208,15 +271,15 @@ namespace butl p = d.c_str (); } - // Note that VC's implementations of _stat64() follows junctions and fails - // for dangling ones. MinGW GCC's implementation returns the information - // about the junction itself. That's why we handle junctions specially, - // not relying on _stat64(). + // Note that VC's implementations of _stat64() follows reparse points and + // fails for dangling ones. MinGW GCC's implementation returns the + // information about the reparse itself. That's why we handle junctions + // and symlinks specially, not relying on _stat64(). // DWORD a (GetFileAttributesA (p)); if (a == INVALID_FILE_ATTRIBUTES) // Presumably not exists. return make_pair (false, entry_stat {entry_type::unknown, 0}); - +/* if (junction (a)) { if (!fl) @@ -226,6 +289,14 @@ namespace butl ? make_pair (true, entry_stat {entry_type::directory, 0}) : make_pair (false, entry_stat {entry_type::unknown, 0}); } +*/ + if (symlink (a)) + { + if (!fl) + return make_pair (true, entry_stat {entry_type::symlink, 0}); + + return symlink_target_entry (p, ie); + } entry_type et (entry_type::unknown); struct __stat64 s; // For 64-bit size. @@ -494,7 +565,31 @@ namespace butl mksymlink (const path& target, const path& link, bool dir) { if (!dir) + { + // Try to create a symbolic link and assume symlinks are not supported + // on error, unless target or link paths is invalid. + // + // + if (CreateSymbolicLinkA (link.string ().c_str (), + target.string ().c_str (), + SYMBOLIC_LINK_FLAG_ALLOW_UNPRIVILEGED_CREATE)) + return; + + if (GetLastError () == ERROR_INVALID_PARAMETER) + { + auto invalid = [] (const path& p) + { + return GetFileAttributesA (p.string ().c_str ()) == + INVALID_FILE_ATTRIBUTES && + GetLastError () == ERROR_INVALID_PARAMETER; + }; + + if (invalid (target) || invalid (link)) + throw_generic_error (EINVAL); + } + throw_generic_error (ENOSYS, "file symlinks not supported"); + } dir_path ld (path_cast (link)); diff --git a/tests/link/driver.cxx b/tests/link/driver.cxx index 96ac880..79f381d 100644 --- a/tests/link/driver.cxx +++ b/tests/link/driver.cxx @@ -35,18 +35,33 @@ using namespace butl; static const char text[] = "ABCDEF"; +enum class mklink +{ + sym, + hard, + any +}; + static bool -link_file (const path& target, const path& link, bool hard, bool check_content) +link_file (const path& target, const path& link, mklink ml, bool check_content) { try { - if (hard) - mkhardlink (target, link); - else - mksymlink (target, link); + switch (ml) + { + case mklink::sym: mksymlink (target, link); break; + case mklink::hard: mkhardlink (target, link); break; + case mklink::any: mkanylink (target, link, true /* copy */); break; + } } - catch (const system_error&) + catch (const system_error& e) + { + cerr << e << endl; + return false; + } + catch (const pair& e) { + cerr << e.second << endl; return false; } @@ -139,22 +154,26 @@ main () // Create the file hard link. // - assert (link_file (fp, td / path ("hlink"), true, true)); + assert (link_file (fp, td / path ("hlink"), mklink::hard, true)); #ifndef _WIN32 // Create the file symlink using an absolute path. // - assert (link_file (fp, td / path ("slink"), false, true)); + assert (link_file (fp, td / path ("slink"), mklink::sym, true)); // Create the file symlink using a relative path. // - assert (link_file (fn, td / path ("rslink"), false, true)); + assert (link_file (fn, td / path ("rslink"), mklink::sym, true)); // Create the file symlink using an unexistent file path. // - assert (link_file (fp + "-a", td / path ("sa"), false, false)); + assert (link_file (fp + "-a", td / path ("sa"), mklink::sym, false)); #endif + // Create the file any link. + // + assert (link_file (fp, td / path ("alink"), mklink::any, true)); + // Prepare the target directory. // dir_path dn ("dir"); @@ -169,8 +188,8 @@ main () } #ifndef _WIN32 - assert (link_file (fp, dp / path ("hlink"), true, true)); - assert (link_file (fp, dp / path ("slink"), false, true)); + assert (link_file (fp, dp / path ("hlink"), mklink::hard, true)); + assert (link_file (fp, dp / path ("slink"), mklink::sym, true)); #endif // Create the directory symlink using an absolute path. diff --git a/tests/mventry/testscript b/tests/mventry/testscript index ecd617a..8c41eb4 100644 --- a/tests/mventry/testscript +++ b/tests/mventry/testscript @@ -130,7 +130,7 @@ if ($test.target == $build.host) : target stays intact. : echo 'foo' >=a; - $lns; + $lns &b; echo 'bar' >=c &!c; $* c b; cat a >'foo'; @@ -149,6 +149,7 @@ if ($test.target == $build.host) : dir : { +#\ : from : : Make sure that if source is a symlink it refers the same target after @@ -160,7 +161,7 @@ if ($test.target == $build.host) touch a/b; test -f c/b; test -d b == 1 - +#\ : to : : Make sure that if destination is a symlink it is get overwritten and diff --git a/tests/path-entry/driver.cxx b/tests/path-entry/driver.cxx index d48bf49..e4dddf3 100644 --- a/tests/path-entry/driver.cxx +++ b/tests/path-entry/driver.cxx @@ -25,20 +25,36 @@ import butl.filesystem; using namespace std; using namespace butl; -// Usage: argv[0] +// Usage: argv[0] [-l] // // If path entry exists then print it's type and size (meaningful for the // regular file only) to STDOUT, and exit with the zero code. Otherwise exit // with the one code. Don't follow symlink. On failure print the error // description to STDERR and exit with the two code. // +// -l +// Follow symlinks. +// int main (int argc, const char* argv[]) try { - assert (argc == 2); + bool follow_symlinks (false); + + int i (1); + for (; i != argc; ++i) + { + string v (argv[i]); + + if (v == "-l") + follow_symlinks = true; + else + break; + } + + assert (i == argc - 1); - auto es (path_entry (argv[1])); + auto es (path_entry (argv[i], follow_symlinks)); if (!es.first) return 1; diff --git a/tests/path-entry/testscript b/tests/path-entry/testscript index 456f96f..35b6f6f 100644 --- a/tests/path-entry/testscript +++ b/tests/path-entry/testscript @@ -25,6 +25,15 @@ directory /. EOO + + : followed-symlink + : + cat <:'abc' >=f; + ln -s f l; + $* -l l >>EOO + regular + 3 + EOO } : non-existent -- cgit v1.1