| // Copyright 2012 Google Inc. All Rights Reserved. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "deps_log.h" |
| |
| #include <assert.h> |
| #include <stdio.h> |
| #include <errno.h> |
| #include <string.h> |
| #ifndef _WIN32 |
| #include <unistd.h> |
| #endif |
| |
| #include "graph.h" |
| #include "metrics.h" |
| #include "state.h" |
| #include "util.h" |
| |
| // The version is stored as 4 bytes after the signature and also serves as a |
| // byte order mark. Signature and version combined are 16 bytes long. |
| const char kFileSignature[] = "# ninjadeps\n"; |
| const int kCurrentVersion = 1; |
| |
| DepsLog::~DepsLog() { |
| Close(); |
| } |
| |
| bool DepsLog::OpenForWrite(const string& path, string* err) { |
| if (needs_recompaction_) { |
| Close(); |
| if (!Recompact(path, err)) |
| return false; |
| } |
| |
| file_ = fopen(path.c_str(), "ab"); |
| if (!file_) { |
| *err = strerror(errno); |
| return false; |
| } |
| SetCloseOnExec(fileno(file_)); |
| |
| // Opening a file in append mode doesn't set the file pointer to the file's |
| // end on Windows. Do that explicitly. |
| fseek(file_, 0, SEEK_END); |
| |
| if (ftell(file_) == 0) { |
| if (fwrite(kFileSignature, sizeof(kFileSignature) - 1, 1, file_) < 1) { |
| *err = strerror(errno); |
| return false; |
| } |
| if (fwrite(&kCurrentVersion, 4, 1, file_) < 1) { |
| *err = strerror(errno); |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool DepsLog::RecordDeps(Node* node, TimeStamp mtime, |
| const vector<Node*>& nodes) { |
| return RecordDeps(node, mtime, nodes.size(), |
| nodes.empty() ? NULL : (Node**)&nodes.front()); |
| } |
| |
| bool DepsLog::RecordDeps(Node* node, TimeStamp mtime, |
| int node_count, Node** nodes) { |
| // Track whether there's any new data to be recorded. |
| bool made_change = false; |
| |
| // Assign ids to all nodes that are missing one. |
| if (node->id() < 0) { |
| RecordId(node); |
| made_change = true; |
| } |
| for (int i = 0; i < node_count; ++i) { |
| if (nodes[i]->id() < 0) { |
| RecordId(nodes[i]); |
| made_change = true; |
| } |
| } |
| |
| // See if the new data is different than the existing data, if any. |
| if (!made_change) { |
| Deps* deps = GetDeps(node); |
| if (!deps || |
| deps->mtime != mtime || |
| deps->node_count != node_count) { |
| made_change = true; |
| } else { |
| for (int i = 0; i < node_count; ++i) { |
| if (deps->nodes[i] != nodes[i]) { |
| made_change = true; |
| break; |
| } |
| } |
| } |
| } |
| |
| // Don't write anything if there's no new info. |
| if (!made_change) |
| return true; |
| |
| // Update on-disk representation. |
| uint16_t size = 4 * (1 + 1 + (uint16_t)node_count); |
| size |= 0x8000; // Deps record: set high bit. |
| fwrite(&size, 2, 1, file_); |
| int id = node->id(); |
| fwrite(&id, 4, 1, file_); |
| int timestamp = mtime; |
| fwrite(×tamp, 4, 1, file_); |
| for (int i = 0; i < node_count; ++i) { |
| id = nodes[i]->id(); |
| fwrite(&id, 4, 1, file_); |
| } |
| |
| // Update in-memory representation. |
| Deps* deps = new Deps(mtime, node_count); |
| for (int i = 0; i < node_count; ++i) |
| deps->nodes[i] = nodes[i]; |
| UpdateDeps(node->id(), deps); |
| |
| return true; |
| } |
| |
| void DepsLog::Close() { |
| if (file_) |
| fclose(file_); |
| file_ = NULL; |
| } |
| |
| bool DepsLog::Load(const string& path, State* state, string* err) { |
| METRIC_RECORD(".ninja_deps load"); |
| char buf[32 << 10]; |
| FILE* f = fopen(path.c_str(), "rb"); |
| if (!f) { |
| if (errno == ENOENT) |
| return true; |
| *err = strerror(errno); |
| return false; |
| } |
| |
| bool valid_header = true; |
| int version = 0; |
| if (!fgets(buf, sizeof(buf), f) || fread(&version, 4, 1, f) < 1) |
| valid_header = false; |
| if (!valid_header || strcmp(buf, kFileSignature) != 0 || |
| version != kCurrentVersion) { |
| *err = "bad deps log signature or version; starting over"; |
| fclose(f); |
| unlink(path.c_str()); |
| // Don't report this as a failure. An empty deps log will cause |
| // us to rebuild the outputs anyway. |
| return true; |
| } |
| |
| long offset; |
| bool read_failed = false; |
| int unique_dep_record_count = 0; |
| int total_dep_record_count = 0; |
| for (;;) { |
| offset = ftell(f); |
| |
| uint16_t size; |
| if (fread(&size, 2, 1, f) < 1) { |
| if (!feof(f)) |
| read_failed = true; |
| break; |
| } |
| bool is_deps = (size >> 15) != 0; |
| size = size & 0x7FFF; |
| |
| if (fread(buf, size, 1, f) < 1) { |
| read_failed = true; |
| break; |
| } |
| |
| if (is_deps) { |
| assert(size % 4 == 0); |
| int* deps_data = reinterpret_cast<int*>(buf); |
| int out_id = deps_data[0]; |
| int mtime = deps_data[1]; |
| deps_data += 2; |
| int deps_count = (size / 4) - 2; |
| |
| Deps* deps = new Deps(mtime, deps_count); |
| for (int i = 0; i < deps_count; ++i) { |
| assert(deps_data[i] < (int)nodes_.size()); |
| assert(nodes_[deps_data[i]]); |
| deps->nodes[i] = nodes_[deps_data[i]]; |
| } |
| |
| total_dep_record_count++; |
| if (!UpdateDeps(out_id, deps)) |
| ++unique_dep_record_count; |
| } else { |
| StringPiece path(buf, size); |
| Node* node = state->GetNode(path); |
| assert(node->id() < 0); |
| node->set_id(nodes_.size()); |
| nodes_.push_back(node); |
| } |
| } |
| |
| if (read_failed) { |
| // An error occurred while loading; try to recover by truncating the |
| // file to the last fully-read record. |
| if (ferror(f)) { |
| *err = strerror(ferror(f)); |
| } else { |
| *err = "premature end of file"; |
| } |
| fclose(f); |
| |
| if (!Truncate(path.c_str(), offset, err)) |
| return false; |
| |
| // The truncate succeeded; we'll just report the load error as a |
| // warning because the build can proceed. |
| *err += "; recovering"; |
| return true; |
| } |
| |
| fclose(f); |
| |
| // Rebuild the log if there are too many dead records. |
| int kMinCompactionEntryCount = 1000; |
| int kCompactionRatio = 3; |
| if (total_dep_record_count > kMinCompactionEntryCount && |
| total_dep_record_count > unique_dep_record_count * kCompactionRatio) { |
| needs_recompaction_ = true; |
| } |
| |
| return true; |
| } |
| |
| DepsLog::Deps* DepsLog::GetDeps(Node* node) { |
| // Abort if the node has no id (never referenced in the deps) or if |
| // there's no deps recorded for the node. |
| if (node->id() < 0 || node->id() >= (int)deps_.size()) |
| return NULL; |
| return deps_[node->id()]; |
| } |
| |
| bool DepsLog::Recompact(const string& path, string* err) { |
| METRIC_RECORD(".ninja_deps recompact"); |
| printf("Recompacting deps...\n"); |
| |
| string temp_path = path + ".recompact"; |
| |
| // OpenForWrite() opens for append. Make sure it's not appending to a |
| // left-over file from a previous recompaction attempt that crashed somehow. |
| unlink(temp_path.c_str()); |
| |
| DepsLog new_log; |
| if (!new_log.OpenForWrite(temp_path, err)) |
| return false; |
| |
| // Clear all known ids so that new ones can be reassigned. The new indices |
| // will refer to the ordering in new_log, not in the current log. |
| for (vector<Node*>::iterator i = nodes_.begin(); i != nodes_.end(); ++i) |
| (*i)->set_id(-1); |
| |
| // Write out all deps again. |
| for (int old_id = 0; old_id < (int)deps_.size(); ++old_id) { |
| Deps* deps = deps_[old_id]; |
| if (!deps) continue; // If nodes_[old_id] is a leaf, it has no deps. |
| |
| if (!new_log.RecordDeps(nodes_[old_id], deps->mtime, |
| deps->node_count, deps->nodes)) { |
| new_log.Close(); |
| return false; |
| } |
| } |
| |
| new_log.Close(); |
| |
| // All nodes now have ids that refer to new_log, so steal its data. |
| deps_.swap(new_log.deps_); |
| nodes_.swap(new_log.nodes_); |
| |
| if (unlink(path.c_str()) < 0) { |
| *err = strerror(errno); |
| return false; |
| } |
| |
| if (rename(temp_path.c_str(), path.c_str()) < 0) { |
| *err = strerror(errno); |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool DepsLog::UpdateDeps(int out_id, Deps* deps) { |
| if (out_id >= (int)deps_.size()) |
| deps_.resize(out_id + 1); |
| |
| bool delete_old = deps_[out_id] != NULL; |
| if (delete_old) |
| delete deps_[out_id]; |
| deps_[out_id] = deps; |
| return delete_old; |
| } |
| |
| bool DepsLog::RecordId(Node* node) { |
| uint16_t size = (uint16_t)node->path().size(); |
| fwrite(&size, 2, 1, file_); |
| fwrite(node->path().data(), node->path().size(), 1, file_); |
| |
| node->set_id(nodes_.size()); |
| nodes_.push_back(node); |
| |
| return true; |
| } |