gn: Support build directories outside the source tree.
The main use-case is to support using a fast SSD or ramdisk for the
build directory, but a slower persistent disk for the source code.
The general idea behind this change is modifying
- RebaseSourceAbsolutePath()
- SourceDir::ResolveRelativeFile()
- SourceDir::ResolveRelativeDir()
- GetOutputDirForSourceDirAsOutputFile()
- PathOutput
to work with paths reaching out of the source directory.
Thanks to jam@ for the Windows-fixes.
BUG=343728
TEST=New unit tests + Unit tests pass.
TEST=`gn gen /ssd/out/Debug && ninja -C /ssd/out/Debug` work as expected.
Review URL: https://codereview.chromium.org/630223002
Cr-Commit-Position: refs/heads/master@{#303719}
diff --git a/tools/gn/filesystem_utils.cc b/tools/gn/filesystem_utils.cc
index 1e4194c..ebfb942 100644
--- a/tools/gn/filesystem_utils.cc
+++ b/tools/gn/filesystem_utils.cc
@@ -421,27 +421,6 @@
#endif
}
-std::string InvertDir(const SourceDir& path) {
- const std::string value = path.value();
- if (value.empty())
- return std::string();
-
- DCHECK(value[0] == '/');
- size_t begin_index = 1;
-
- // If the input begins with two slashes, skip over both (this is a
- // source-relative dir). These must be forward slashes only.
- if (value.size() > 1 && value[1] == '/')
- begin_index = 2;
-
- std::string ret;
- for (size_t i = begin_index; i < value.size(); i++) {
- if (IsSlash(value[i]))
- ret.append("../");
- }
- return ret;
-}
-
void NormalizePath(std::string* path) {
char* pathbuf = path->empty() ? NULL : &(*path)[0];
@@ -539,18 +518,13 @@
#endif
}
-std::string RebaseSourceAbsolutePath(const std::string& input,
- const SourceDir& dest_dir) {
- CHECK(input.size() >= 2 && input[0] == '/' && input[1] == '/')
- << "Input to rebase isn't source-absolute: " << input;
- CHECK(dest_dir.is_source_absolute())
- << "Dir to rebase to isn't source-absolute: " << dest_dir.value();
-
- const std::string& dest = dest_dir.value();
+std::string MakeRelativePath(const std::string& input,
+ const std::string& dest) {
+ std::string ret;
// Skip the common prefixes of the source and dest as long as they end in
// a [back]slash.
- size_t common_prefix_len = 2; // The beginning two "//" are always the same.
+ size_t common_prefix_len = 0;
size_t max_common_length = std::min(input.size(), dest.size());
for (size_t i = common_prefix_len; i < max_common_length; i++) {
if (IsSlash(input[i]) && IsSlash(dest[i]))
@@ -560,7 +534,6 @@
}
// Invert the dest dir starting from the end of the common prefix.
- std::string ret;
for (size_t i = common_prefix_len; i < dest.size(); i++) {
if (IsSlash(dest[i]))
ret.append("../");
@@ -576,6 +549,58 @@
return ret;
}
+std::string RebasePath(const std::string& input,
+ const SourceDir& dest_dir,
+ const base::StringPiece& source_root) {
+ std::string ret;
+ DCHECK(source_root.empty() || !source_root.ends_with("/"));
+
+ bool input_is_source_path = (input.size() >= 2 &&
+ input[0] == '/' && input[1] == '/');
+
+ if (!source_root.empty() &&
+ (!input_is_source_path || !dest_dir.is_source_absolute())) {
+ std::string input_full;
+ std::string dest_full;
+ if (input_is_source_path) {
+ source_root.AppendToString(&input_full);
+ input_full.push_back('/');
+ input_full.append(input, 2, std::string::npos);
+ } else {
+ input_full.append(input);
+ }
+ if (dest_dir.is_source_absolute()) {
+ source_root.AppendToString(&dest_full);
+ dest_full.push_back('/');
+ dest_full.append(dest_dir.value(), 2, std::string::npos);
+ } else {
+#if defined(OS_WIN)
+ // On Windows, SourceDir system-absolute paths start
+ // with /, e.g. "/C:/foo/bar".
+ const std::string& value = dest_dir.value();
+ if (value.size() > 2 && value[2] == ':')
+ dest_full.append(dest_dir.value().substr(1));
+ else
+ dest_full.append(dest_dir.value());
+#else
+ dest_full.append(dest_dir.value());
+#endif
+ }
+ bool remove_slash = false;
+ if (!EndsWithSlash(input_full)) {
+ input_full.push_back('/');
+ remove_slash = true;
+ }
+ ret = MakeRelativePath(input_full, dest_full);
+ if (remove_slash && ret.size() > 1)
+ ret.resize(ret.size() - 1);
+ return ret;
+ }
+
+ ret = MakeRelativePath(input, dest_dir.value());
+ return ret;
+}
+
std::string DirectoryWithNoLastSlash(const SourceDir& dir) {
std::string ret;
@@ -698,6 +723,16 @@
// slashes to append to the toolchain object directory.
result.value().append(&source_dir.value()[2],
source_dir.value().size() - 2);
+ } else {
+ // system-absolute
+ const std::string& build_dir =
+ settings->build_settings()->build_dir().value();
+
+ if (StartsWithASCII(source_dir.value(), build_dir, true)) {
+ size_t build_dir_size = build_dir.size();
+ result.value().append(&source_dir.value()[build_dir_size],
+ source_dir.value().size() - build_dir_size);
+ }
}
return result;
}
