Support: Add PathV2 implementation.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@120329 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Support/PathV2.cpp b/lib/Support/PathV2.cpp
new file mode 100644
index 0000000..115f294
--- /dev/null
+++ b/lib/Support/PathV2.cpp
@@ -0,0 +1,409 @@
+//===-- PathV2.cpp - Implement OS Path Concept ------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the operating system PathV2 API.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Support/PathV2.h"
+#include "llvm/Support/ErrorHandling.h"
+#include <cctype>
+
+namespace {
+ using llvm::StringRef;
+
+ bool is_separator(const char value) {
+ switch(value) {
+#ifdef LLVM_ON_WIN32
+ case '\\': // fall through
+#endif
+ case '/': return true;
+ default: return false;
+ }
+ }
+
+#ifdef LLVM_ON_WIN32
+ const StringRef separators = "\\/";
+ const char prefered_separator = '\\';
+#else
+ const StringRef separators = "/";
+ const char prefered_separator = '/';
+#endif
+
+ StringRef find_first_component(const StringRef &path) {
+ // Look for this first component in the following order.
+ // * empty (in this case we return an empty string)
+ // * either C: or {//,\\}net.
+ // * {/,\}
+ // * {.,..}
+ // * {file,directory}name
+
+ if (path.empty())
+ return path;
+
+ // C:
+ if (path.size() >= 2 && std::isalpha(path[0]) && path[1] == ':')
+ return StringRef(path.begin(), 2);
+
+ // //net
+ if ((path.size() > 2) &&
+ (path.startswith("\\\\") || path.startswith("//")) &&
+ (path[2] != '\\' && path[2] != '/')) {
+ // Find the next directory separator.
+ size_t end = path.find_first_of("\\/", 2);
+ if (end == StringRef::npos)
+ return path;
+ else
+ return StringRef(path.begin(), end);
+ }
+
+ // {/,\}
+ if (path[0] == '\\' || path[0] == '/')
+ return StringRef(path.begin(), 1);
+
+ if (path.startswith(".."))
+ return StringRef(path.begin(), 2);
+
+ if (path[0] == '.')
+ return StringRef(path.begin(), 1);
+
+ // * {file,directory}name
+ size_t end = path.find_first_of("\\/", 2);
+ if (end == StringRef::npos)
+ return path;
+ else
+ return StringRef(path.begin(), end);
+
+ return StringRef();
+ }
+}
+
+namespace llvm {
+namespace sys {
+namespace path {
+
+const_iterator begin(const StringRef &path) {
+ const_iterator i;
+ i.Path = path;
+ i.Component = find_first_component(path);
+ i.Position = 0;
+ return i;
+}
+
+const_iterator end(const StringRef &path) {
+ const_iterator i;
+ i.Path = path;
+ i.Position = path.size();
+ return i;
+}
+
+const_iterator::reference const_iterator::operator*() const {
+ return Component;
+}
+
+const_iterator::pointer const_iterator::operator->() const {
+ return &Component;
+}
+
+const_iterator &const_iterator::operator++() {
+ assert(Position < Path.size() && "Tried to increment past end!");
+
+ // Increment Position to past the current component
+ Position += Component.size();
+
+ // Check for end.
+ if (Position == Path.size()) {
+ Component = StringRef();
+ return *this;
+ }
+
+ // Both POSIX and Windows treat paths that begin with exactly two separators
+ // specially.
+ bool was_net = Component.size() > 2 &&
+ is_separator(Component[0]) &&
+ Component[1] == Component[0] &&
+ !is_separator(Component[2]);
+
+ // Handle separators.
+ if (is_separator(Path[Position])) {
+ // Root dir.
+ if (was_net
+#ifdef LLVM_ON_WIN32
+ // c:/
+ || Component.endswith(":")
+#endif
+ ) {
+ Component = StringRef(Path.begin() + Position, 1);
+ return *this;
+ }
+
+ // Skip extra separators.
+ while (Position != Path.size() &&
+ is_separator(Path[Position])) {
+ ++Position;
+ }
+
+ // Treat trailing '/' as a '.'.
+ if (Position == Path.size()) {
+ --Position;
+ Component = ".";
+ return *this;
+ }
+ }
+
+ // Find next component.
+ size_t end_pos = Path.find_first_of(separators, Position);
+ if (end_pos == StringRef::npos)
+ end_pos = Path.size();
+ Component = StringRef(Path.begin() + Position, end_pos - Position);
+
+ return *this;
+}
+
+bool const_iterator::operator==(const const_iterator &RHS) const {
+ return Path.begin() == RHS.Path.begin() &&
+ Position == RHS.Position;
+}
+
+bool const_iterator::operator!=(const const_iterator &RHS) const {
+ return !(*this == RHS);
+}
+
+error_code root_path(const StringRef &path, StringRef &result) {
+ const_iterator b = begin(path),
+ pos = b,
+ e = end(path);
+ if (b != e) {
+ bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0];
+ bool has_drive =
+#ifdef LLVM_ON_WIN32
+ b->endswith(":");
+#else
+ false;
+#endif
+
+ if (has_net || has_drive) {
+ if ((++pos != e) && is_separator((*pos)[0])) {
+ // {C:/,//net/}, so get the first two components.
+ result = StringRef(path.begin(), b->size() + pos->size());
+ return make_error_code(errc::success);
+ } else {
+ // just {C:,//net}, return the first component.
+ result = *b;
+ return make_error_code(errc::success);
+ }
+ }
+
+ // POSIX style root directory.
+ if (is_separator((*b)[0])) {
+ result = *b;
+ return make_error_code(errc::success);
+ }
+
+ // No root_path.
+ result = StringRef();
+ return make_error_code(errc::success);
+ }
+
+ // No path :(.
+ result = StringRef();
+ return make_error_code(errc::success);
+}
+
+error_code root_name(const StringRef &path, StringRef &result) {
+ const_iterator b = begin(path),
+ e = end(path);
+ if (b != e) {
+ bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0];
+ bool has_drive =
+#ifdef LLVM_ON_WIN32
+ b->endswith(":");
+#else
+ false;
+#endif
+
+ if (has_net || has_drive) {
+ // just {C:,//net}, return the first component.
+ result = *b;
+ return make_error_code(errc::success);
+ }
+ }
+
+ // No path or no name.
+ result = StringRef();
+ return make_error_code(errc::success);
+}
+
+error_code root_directory(const StringRef &path, StringRef &result) {
+ const_iterator b = begin(path),
+ pos = b,
+ e = end(path);
+ if (b != e) {
+ bool has_net = b->size() > 2 && is_separator((*b)[0]) && (*b)[1] == (*b)[0];
+ bool has_drive =
+#ifdef LLVM_ON_WIN32
+ b->endswith(":");
+#else
+ false;
+#endif
+
+ if ((has_net || has_drive) &&
+ // {C:,//net}, skip to the next component.
+ (++pos != e) && is_separator((*pos)[0])) {
+ result = *pos;
+ return make_error_code(errc::success);
+ }
+
+ // POSIX style root directory.
+ if (!has_net && is_separator((*b)[0])) {
+ result = *b;
+ return make_error_code(errc::success);
+ }
+ }
+
+ // No path or no root.
+ result = StringRef();
+ return make_error_code(errc::success);
+}
+
+error_code has_root_name(const Twine &path, bool &result) {
+ SmallString<128> storage;
+ StringRef p = path.toStringRef(storage);
+
+ if (error_code ec = root_name(p, p)) return ec;
+ result = !p.empty();
+ return make_error_code(errc::success);
+}
+
+error_code has_root_directory(const Twine &path, bool &result) {
+ SmallString<128> storage;
+ StringRef p = path.toStringRef(storage);
+
+ if (error_code ec = root_directory(p, p)) return ec;
+ result = !p.empty();
+ return make_error_code(errc::success);
+}
+
+error_code relative_path(const StringRef &path, StringRef &result) {
+ StringRef root;
+ if (error_code ec = root_path(path, root)) return ec;
+ result = StringRef(path.begin() + root.size(), path.size() - root.size());
+ return make_error_code(errc::success);
+}
+
+error_code append(SmallVectorImpl<char> &path, const Twine &a,
+ const Twine &b,
+ const Twine &c,
+ const Twine &d) {
+ SmallString<32> a_storage;
+ SmallString<32> b_storage;
+ SmallString<32> c_storage;
+ SmallString<32> d_storage;
+
+ SmallVector<StringRef, 4> components;
+ if (!a.isTriviallyEmpty()) components.push_back(a.toStringRef(a_storage));
+ if (!b.isTriviallyEmpty()) components.push_back(b.toStringRef(b_storage));
+ if (!c.isTriviallyEmpty()) components.push_back(c.toStringRef(c_storage));
+ if (!d.isTriviallyEmpty()) components.push_back(d.toStringRef(d_storage));
+
+ for (SmallVectorImpl<StringRef>::const_iterator i = components.begin(),
+ e = components.end();
+ i != e; ++i) {
+ bool path_has_sep = !path.empty() && is_separator(path[path.size() - 1]);
+ bool component_has_sep = !i->empty() && is_separator((*i)[0]);
+ bool is_root_name;
+ if (error_code ec = has_root_name(*i, is_root_name)) return ec;
+
+ if (path_has_sep) {
+ // Strip separators from beginning of component.
+ size_t loc = i->find_first_not_of(separators);
+ StringRef c = StringRef(i->begin() + loc, i->size() - loc);
+
+ // Append it.
+ path.append(c.begin(), c.end());
+ continue;
+ }
+
+ if (!component_has_sep && !(path.empty() && is_root_name)) {
+ // Add a separator.
+ path.push_back(prefered_separator);
+ }
+
+ path.append(i->begin(), i->end());
+ }
+
+ return make_error_code(errc::success);
+}
+
+error_code make_absolute(SmallVectorImpl<char> &path) {
+ StringRef p(path.data(), path.size());
+
+ bool rootName, rootDirectory;
+ if (error_code ec = has_root_name(p, rootName)) return ec;
+ if (error_code ec = has_root_directory(p, rootDirectory)) return ec;
+
+ // Already absolute.
+ if (rootName && rootDirectory)
+ return make_error_code(errc::success);
+
+ // All of the following conditions will need the current directory.
+ SmallString<128> current_dir;
+ if (error_code ec = current_path(current_dir)) return ec;
+
+ // Relative path. Prepend the current directory.
+ if (!rootName && !rootDirectory) {
+ // Append path to the current directory.
+ if (error_code ec = append(current_dir, p)) return ec;
+ // Set path to the result.
+ path.swap(current_dir);
+ return make_error_code(errc::success);
+ }
+
+ if (!rootName && rootDirectory) {
+ StringRef cdrn;
+ if (error_code ec = root_name(current_dir, cdrn)) return ec;
+ SmallString<128> curDirRootName(cdrn.begin(), cdrn.end());
+ if (error_code ec = append(curDirRootName, p)) return ec;
+ // Set path to the result.
+ path.swap(curDirRootName);
+ return make_error_code(errc::success);
+ }
+
+ if (rootName && !rootDirectory) {
+ StringRef pRootName;
+ StringRef bRootDirectory;
+ StringRef bRelativePath;
+ StringRef pRelativePath;
+ if (error_code ec = root_name(p, pRootName)) return ec;
+ if (error_code ec = root_directory(current_dir, bRootDirectory)) return ec;
+ if (error_code ec = relative_path(current_dir, bRelativePath)) return ec;
+ if (error_code ec = relative_path(p, pRelativePath)) return ec;
+
+ SmallString<128> res;
+ if (error_code ec = append(res, pRootName, bRootDirectory,
+ bRelativePath, pRelativePath)) return ec;
+ path.swap(res);
+ return make_error_code(errc::success);
+ }
+
+ llvm_unreachable("All rootName and rootDirectory combinations should have "
+ "occurred above!");
+}
+
+}
+}
+}
+
+// Include the truly platform-specific parts.
+#if defined(LLVM_ON_UNIX)
+#include "Unix/PathV2.inc"
+#endif
+#if defined(LLVM_ON_WIN32)
+#include "Windows/PathV2.inc"
+#endif