tools/gn/command_path.cc - chromium/src - Git at Google

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.

 #include <stddef.h>

 #include <algorithm>

 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/strings/stringprintf.h"
 #include "tools/gn/commands.h"
 #include "tools/gn/setup.h"
 #include "tools/gn/standard_out.h"

 namespace commands {

 namespace {

 enum class DepType {
   NONE,
   PUBLIC,
   PRIVATE,
   DATA
 };

 // The dependency paths are stored in a vector. Assuming the chain:
 //    A --[public]--> B --[private]--> C
 // The stack will look like:
 //    [0] = A, NONE (this has no dep type since nobody depends on it)
 //    [1] = B, PUBLIC
 //    [2] = C, PRIVATE
 using TargetDep = std::pair<const Target*, DepType>;
 using PathVector = std::vector<TargetDep>;

 // How to search.
 enum class PrivateDeps { INCLUDE, EXCLUDE };
 enum class DataDeps { INCLUDE, EXCLUDE };
 enum class PrintWhat { ONE, ALL };

 struct Options {
   Options()
       : print_what(PrintWhat::ONE),
         public_only(false),
         with_data(false) {
   }

   PrintWhat print_what;
   bool public_only;
   bool with_data;
 };

 typedef std::list<PathVector> WorkQueue;

 struct Stats {
   Stats() : public_paths(0), other_paths(0) {
   }

   int total_paths() const { return public_paths + other_paths; }

   int public_paths;
   int other_paths;

   // Stores targets that have a path to the destination, and whether that
   // path is public, private, or data.
   std::map<const Target*, DepType> found_paths;
 };

 // If the implicit_last_dep is not "none", this type indicates the
 // classification of the elided last part of path.
 DepType ClassifyPath(const PathVector& path, DepType implicit_last_dep) {
   DepType result;
   if (implicit_last_dep != DepType::NONE)
     result = implicit_last_dep;
   else
     result = DepType::PUBLIC;

   // Skip the 0th one since that is always NONE.
   for (size_t i = 1; i < path.size(); i++) {
     // PRIVATE overrides PUBLIC, and DATA overrides everything (the idea is
     // to find the worst link in the path).
     if (path[i].second == DepType::PRIVATE) {
       if (result == DepType::PUBLIC)
         result = DepType::PRIVATE;
     } else if (path[i].second == DepType::DATA) {
       result = DepType::DATA;
     }
   }
   return result;
 }

 const char* StringForDepType(DepType type) {
   switch(type) {
     case DepType::PUBLIC:
       return "public";
     case DepType::PRIVATE:
       return "private";
     case DepType::DATA:
       return "data";
       break;
     case DepType::NONE:
     default:
       return "";
   }
 }

 // Prints the given path. If the implicit_last_dep is not "none", the last
 // dependency will show an elided dependency with the given annotation.
 void PrintPath(const PathVector& path, DepType implicit_last_dep) {
   if (path.empty())
     return;

   // Don't print toolchains unless they differ from the first target.
   const Label& default_toolchain = path[0].first->label().GetToolchainLabel();

   for (size_t i = 0; i < path.size(); i++) {
     OutputString(path[i].first->label().GetUserVisibleName(default_toolchain));

     // Output dependency type.
     if (i == path.size() - 1) {
       // Last one either gets the implicit last dep type or nothing.
       if (implicit_last_dep != DepType::NONE) {
         OutputString(std::string(" --> see ") +
                      StringForDepType(implicit_last_dep) +
                      " chain printed above...", DECORATION_DIM);
       }
     } else {
       // Take type from the next entry.
       OutputString(std::string(" --[") + StringForDepType(path[i + 1].second) +
                    "]-->", DECORATION_DIM);
     }
     OutputString("\n");
   }

   OutputString("\n");
 }

 void InsertTargetsIntoFoundPaths(const PathVector& path,
                                  DepType implicit_last_dep,
                                  Stats* stats) {
   DepType type = ClassifyPath(path, implicit_last_dep);

   bool inserted = false;

   // Don't try to insert the 0th item in the list which is the "from" target.
   // The search will be run more than once (for the different path types) and
   // if the "from" target was in the list, subsequent passes could never run
   // the starting point is alredy in the list of targets considered).
   //
   // One might imagine an alternate implementation where all items are counted
   // here but the "from" item is erased at the beginning of each search, but
   // that will mess up the metrics (the private search pass will find the
   // same public paths as the previous public pass, "inserted" will be true
   // here since the item wasn't found, and the public path will be
   // double-counted in the stats.
   for (size_t i = 1; i < path.size(); i++) {
     const auto& pair = path[i];

     // Don't overwrite an existing one. The algorithm works by first doing
     // public, then private, then data, so anything already there is guaranteed
     // at least as good as our addition.
     if (stats->found_paths.find(pair.first) == stats->found_paths.end()) {
       stats->found_paths.insert(std::make_pair(pair.first, type));
       inserted = true;
     }
   }

   if (inserted) {
     // Only count this path in the stats if any part of it was actually new.
     if (type == DepType::PUBLIC)
       stats->public_paths++;
     else
       stats->other_paths++;
   }
 }

 void BreadthFirstSearch(const Target* from, const Target* to,
                         PrivateDeps private_deps, DataDeps data_deps,
                         PrintWhat print_what,
                         Stats* stats) {
   // Seed the initial stack with just the "from" target.
   PathVector initial_stack;
   initial_stack.emplace_back(from, DepType::NONE);
   WorkQueue work_queue;
   work_queue.push_back(initial_stack);

   // Track checked targets to avoid checking the same once more than once.
   std::set<const Target*> visited;

   while (!work_queue.empty()) {
     PathVector current_path = work_queue.front();
     work_queue.pop_front();

     const Target* current_target = current_path.back().first;

     if (current_target == to) {
       // Found a new path.
       if (stats->total_paths() == 0 || print_what == PrintWhat::ALL)
         PrintPath(current_path, DepType::NONE);

       // Insert all nodes on the path into the found paths list. Since we're
       // doing search breadth first, we know that the current path is the best
       // path for all nodes on it.
       InsertTargetsIntoFoundPaths(current_path, DepType::NONE, stats);
     } else {
       // Check for a path that connects to an already known-good one. Printing
       // this here will mean the results aren't strictly in depth-first order
       // since there could be many items on the found path this connects to.
       // Doing this here will mean that the output is sorted by length of items
       // printed (with the redundant parts of the path omitted) rather than
       // complete path length.
       const auto& found_current_target =
           stats->found_paths.find(current_target);
       if (found_current_target != stats->found_paths.end()) {
         if (stats->total_paths() == 0 || print_what == PrintWhat::ALL)
           PrintPath(current_path, found_current_target->second);

         // Insert all nodes on the path into the found paths list since we know
         // everything along this path also leads to the destination.
         InsertTargetsIntoFoundPaths(current_path, found_current_target->second,
                                     stats);
         continue;
       }
     }

     // If we've already checked this one, stop. This should be after the above
     // check for a known-good check, because known-good ones will always have
     // been previously visited.
     if (visited.find(current_target) == visited.end())
       visited.insert(current_target);
     else
       continue;

     // Add public deps for this target to the queue.
     for (const auto& pair : current_target->public_deps()) {
       work_queue.push_back(current_path);
       work_queue.back().push_back(TargetDep(pair.ptr, DepType::PUBLIC));
     }

     if (private_deps == PrivateDeps::INCLUDE) {
       // Add private deps.
       for (const auto& pair : current_target->private_deps()) {
         work_queue.push_back(current_path);
         work_queue.back().push_back(
             TargetDep(pair.ptr, DepType::PRIVATE));
       }
     }

     if (data_deps == DataDeps::INCLUDE) {
       // Add data deps.
       for (const auto& pair : current_target->data_deps()) {
         work_queue.push_back(current_path);
         work_queue.back().push_back(TargetDep(pair.ptr, DepType::DATA));
       }
     }
   }
 }

 void DoSearch(const Target* from, const Target* to, const Options& options,
               Stats* stats) {
   BreadthFirstSearch(from, to, PrivateDeps::EXCLUDE, DataDeps::EXCLUDE,
                      options.print_what, stats);
   if (!options.public_only) {
     // Check private deps.
     BreadthFirstSearch(from, to, PrivateDeps::INCLUDE,
                        DataDeps::EXCLUDE, options.print_what, stats);
     if (options.with_data) {
       // Check data deps.
       BreadthFirstSearch(from, to, PrivateDeps::INCLUDE,
                          DataDeps::INCLUDE, options.print_what, stats);
     }
   }
 }

 }  // namespace

 const char kPath[] = "path";
 const char kPath_HelpShort[] =
     "path: Find paths between two targets.";
 const char kPath_Help[] =
     "gn path <out_dir> <target_one> <target_two>\n"
     "\n"
     "  Finds paths of dependencies between two targets. Each unique path\n"
     "  will be printed in one group, and groups will be separate by newlines.\n"
     "  The two targets can appear in either order (paths will be found going\n"
     "  in either direction).\n"
     "\n"
     "  By default, a single path will be printed. If there is a path with\n"
     "  only public dependencies, the shortest public path will be printed.\n"
     "  Otherwise, the shortest path using either public or private\n"
     "  dependencies will be printed. If --with-data is specified, data deps\n"
     "  will also be considered. If there are multiple shortest paths, an\n"
     "  arbitrary one will be selected.\n"
     "\n"
     "Interesting paths\n"
     "\n"
     "  In a large project, there can be 100's of millions of unique paths\n"
     "  between a very high level and a common low-level target. To make the\n"
     "  output more useful (and terminate in a reasonable time), GN will not\n"
     "  revisit sub-paths previously known to lead to the target.\n"
     "\n"
     "Options\n"
     "\n"
     "  --all\n"
     "     Prints all \"interesting\" paths found rather than just the first\n"
     "     one. Public paths will be printed first in order of increasing\n"
     "     length, followed by non-public paths in order of increasing length.\n"
     "\n"
     "  --public\n"
     "     Considers only public paths. Can't be used with --with-data.\n"
     "\n"
     "  --with-data\n"
     "     Additionally follows data deps. Without this flag, only public and\n"
     "     private linked deps will be followed. Can't be used with --public.\n"
     "\n"
     "Example\n"
     "\n"
     "  gn path out/Default //base //tools/gn\n";

 int RunPath(const std::vector<std::string>& args) {
   if (args.size() != 3) {
     Err(Location(), "You're holding it wrong.",
         "Usage: \"gn path <out_dir> <target_one> <target_two>\"")
         .PrintToStdout();
     return 1;
   }

   Setup* setup = new Setup;
   if (!setup->DoSetup(args[0], false))
     return 1;
   if (!setup->Run())
     return 1;

   const Target* target1 = ResolveTargetFromCommandLineString(setup, args[1]);
   if (!target1)
     return 1;
   const Target* target2 = ResolveTargetFromCommandLineString(setup, args[2]);
   if (!target2)
     return 1;

   Options options;
   options.print_what = base::CommandLine::ForCurrentProcess()->HasSwitch("all")
       ? PrintWhat::ALL : PrintWhat::ONE;
   options.public_only =
       base::CommandLine::ForCurrentProcess()->HasSwitch("public");
   options.with_data =
       base::CommandLine::ForCurrentProcess()->HasSwitch("with-data");
   if (options.public_only && options.with_data) {
     Err(Location(), "Can't use --public with --with-data for 'gn path'.",
         "Your zealous over-use of arguments has inevitably resulted in an "
         "invalid\ncombination of flags.").PrintToStdout();
     return 1;
   }

   Stats stats;
   DoSearch(target1, target2, options, &stats);
   if (stats.total_paths() == 0) {
     // If we don't find a path going "forwards", try the reverse direction.
     // Deps can only go in one direction without having a cycle, which will
     // have caused a run failure above.
     DoSearch(target2, target1, options, &stats);
   }

   // This string is inserted in the results to annotate whether the result
   // is only public or includes data deps or not.
   const char* path_annotation = "";
   if (options.public_only)
     path_annotation = "public ";
   else if (!options.with_data)
     path_annotation = "non-data ";

   if (stats.total_paths() == 0) {
     // No results.
     OutputString(base::StringPrintf(
         "No %spaths found between these two targets.\n", path_annotation),
         DECORATION_YELLOW);
   } else if (stats.total_paths() == 1) {
     // Exactly one result.
     OutputString(base::StringPrintf("1 %spath found.", path_annotation),
                  DECORATION_YELLOW);
     if (!options.public_only) {
       if (stats.public_paths)
         OutputString(" It is public.");
       else
         OutputString(" It is not public.");
     }
     OutputString("\n");
   } else {
     if (options.print_what == PrintWhat::ALL) {
       // Showing all paths when there are many.
       OutputString(base::StringPrintf("%d \"interesting\" %spaths found.",
                                       stats.total_paths(), path_annotation),
                    DECORATION_YELLOW);
       if (!options.public_only) {
         OutputString(base::StringPrintf(" %d of them are public.",
                                         stats.public_paths));
       }
       OutputString("\n");
     } else {
       // Showing one path when there are many.
       OutputString(
           base::StringPrintf("Showing one of %d \"interesting\" %spaths.",
                              stats.total_paths(), path_annotation),
           DECORATION_YELLOW);
       if (!options.public_only) {
         OutputString(base::StringPrintf(" %d of them are public.\n",
                                         stats.public_paths));
       }
       OutputString("Use --all to print all paths.\n");
     }
   }
   return 0;
 }

 }  // namespace commands
	// Copyright 2015 The Chromium Authors. All rights reserved.
	// Use of this source code is governed by a BSD-style license that can be
	// found in the LICENSE file.

	#include <stddef.h>

	#include <algorithm>

	#include "base/command_line.h"
	#include "base/containers/hash_tables.h"
	#include "base/strings/stringprintf.h"
	#include "tools/gn/commands.h"
	#include "tools/gn/setup.h"
	#include "tools/gn/standard_out.h"

	namespace commands {

	namespace {

	enum class DepType {
	NONE,
	PUBLIC,
	PRIVATE,
	DATA
	};

	// The dependency paths are stored in a vector. Assuming the chain:
	// A --[public]--> B --[private]--> C
	// The stack will look like:
	// [0] = A, NONE (this has no dep type since nobody depends on it)
	// [1] = B, PUBLIC
	// [2] = C, PRIVATE
	using TargetDep = std::pair<const Target*, DepType>;
	using PathVector = std::vector<TargetDep>;

	// How to search.
	enum class PrivateDeps { INCLUDE, EXCLUDE };
	enum class DataDeps { INCLUDE, EXCLUDE };
	enum class PrintWhat { ONE, ALL };

	struct Options {
	Options()
	: print_what(PrintWhat::ONE),
	public_only(false),
	with_data(false) {
	}

	PrintWhat print_what;
	bool public_only;
	bool with_data;
	};

	typedef std::list<PathVector> WorkQueue;

	struct Stats {
	Stats() : public_paths(0), other_paths(0) {
	}

	int total_paths() const { return public_paths + other_paths; }

	int public_paths;
	int other_paths;

	// Stores targets that have a path to the destination, and whether that
	// path is public, private, or data.
	std::map<const Target*, DepType> found_paths;
	};

	// If the implicit_last_dep is not "none", this type indicates the
	// classification of the elided last part of path.
	DepType ClassifyPath(const PathVector& path, DepType implicit_last_dep) {
	DepType result;
	if (implicit_last_dep != DepType::NONE)
	result = implicit_last_dep;
	else
	result = DepType::PUBLIC;

	// Skip the 0th one since that is always NONE.
	for (size_t i = 1; i < path.size(); i++) {
	// PRIVATE overrides PUBLIC, and DATA overrides everything (the idea is
	// to find the worst link in the path).
	if (path[i].second == DepType::PRIVATE) {
	if (result == DepType::PUBLIC)
	result = DepType::PRIVATE;
	} else if (path[i].second == DepType::DATA) {
	result = DepType::DATA;
	}
	}
	return result;
	}

	const char* StringForDepType(DepType type) {
	switch(type) {
	case DepType::PUBLIC:
	return "public";
	case DepType::PRIVATE:
	return "private";
	case DepType::DATA:
	return "data";
	break;
	case DepType::NONE:
	default:
	return "";
	}
	}

	// Prints the given path. If the implicit_last_dep is not "none", the last
	// dependency will show an elided dependency with the given annotation.
	void PrintPath(const PathVector& path, DepType implicit_last_dep) {
	if (path.empty())
	return;

	// Don't print toolchains unless they differ from the first target.
	const Label& default_toolchain = path[0].first->label().GetToolchainLabel();

	for (size_t i = 0; i < path.size(); i++) {
	OutputString(path[i].first->label().GetUserVisibleName(default_toolchain));

	// Output dependency type.
	if (i == path.size() - 1) {
	// Last one either gets the implicit last dep type or nothing.
	if (implicit_last_dep != DepType::NONE) {
	OutputString(std::string(" --> see ") +
	StringForDepType(implicit_last_dep) +
	" chain printed above...", DECORATION_DIM);
	}
	} else {
	// Take type from the next entry.
	OutputString(std::string(" --[") + StringForDepType(path[i + 1].second) +
	"]-->", DECORATION_DIM);
	}
	OutputString("\n");
	}

	OutputString("\n");
	}

	void InsertTargetsIntoFoundPaths(const PathVector& path,
	DepType implicit_last_dep,
	Stats* stats) {
	DepType type = ClassifyPath(path, implicit_last_dep);

	bool inserted = false;

	// Don't try to insert the 0th item in the list which is the "from" target.
	// The search will be run more than once (for the different path types) and
	// if the "from" target was in the list, subsequent passes could never run
	// the starting point is alredy in the list of targets considered).
	//
	// One might imagine an alternate implementation where all items are counted
	// here but the "from" item is erased at the beginning of each search, but
	// that will mess up the metrics (the private search pass will find the
	// same public paths as the previous public pass, "inserted" will be true
	// here since the item wasn't found, and the public path will be
	// double-counted in the stats.
	for (size_t i = 1; i < path.size(); i++) {
	const auto& pair = path[i];

	// Don't overwrite an existing one. The algorithm works by first doing
	// public, then private, then data, so anything already there is guaranteed
	// at least as good as our addition.
	if (stats->found_paths.find(pair.first) == stats->found_paths.end()) {
	stats->found_paths.insert(std::make_pair(pair.first, type));
	inserted = true;
	}
	}

	if (inserted) {
	// Only count this path in the stats if any part of it was actually new.
	if (type == DepType::PUBLIC)
	stats->public_paths++;
	else
	stats->other_paths++;
	}
	}

	void BreadthFirstSearch(const Target* from, const Target* to,
	PrivateDeps private_deps, DataDeps data_deps,
	PrintWhat print_what,
	Stats* stats) {
	// Seed the initial stack with just the "from" target.
	PathVector initial_stack;
	initial_stack.emplace_back(from, DepType::NONE);
	WorkQueue work_queue;
	work_queue.push_back(initial_stack);

	// Track checked targets to avoid checking the same once more than once.
	std::set<const Target*> visited;

	while (!work_queue.empty()) {
	PathVector current_path = work_queue.front();
	work_queue.pop_front();

	const Target* current_target = current_path.back().first;

	if (current_target == to) {
	// Found a new path.
	if (stats->total_paths() == 0 \|\| print_what == PrintWhat::ALL)
	PrintPath(current_path, DepType::NONE);

	// Insert all nodes on the path into the found paths list. Since we're
	// doing search breadth first, we know that the current path is the best
	// path for all nodes on it.
	InsertTargetsIntoFoundPaths(current_path, DepType::NONE, stats);
	} else {
	// Check for a path that connects to an already known-good one. Printing
	// this here will mean the results aren't strictly in depth-first order
	// since there could be many items on the found path this connects to.
	// Doing this here will mean that the output is sorted by length of items
	// printed (with the redundant parts of the path omitted) rather than
	// complete path length.
	const auto& found_current_target =
	stats->found_paths.find(current_target);
	if (found_current_target != stats->found_paths.end()) {
	if (stats->total_paths() == 0 \|\| print_what == PrintWhat::ALL)
	PrintPath(current_path, found_current_target->second);

	// Insert all nodes on the path into the found paths list since we know
	// everything along this path also leads to the destination.
	InsertTargetsIntoFoundPaths(current_path, found_current_target->second,
	stats);
	continue;
	}
	}

	// If we've already checked this one, stop. This should be after the above
	// check for a known-good check, because known-good ones will always have
	// been previously visited.
	if (visited.find(current_target) == visited.end())
	visited.insert(current_target);
	else
	continue;

	// Add public deps for this target to the queue.
	for (const auto& pair : current_target->public_deps()) {
	work_queue.push_back(current_path);
	work_queue.back().push_back(TargetDep(pair.ptr, DepType::PUBLIC));
	}

	if (private_deps == PrivateDeps::INCLUDE) {
	// Add private deps.
	for (const auto& pair : current_target->private_deps()) {
	work_queue.push_back(current_path);
	work_queue.back().push_back(
	TargetDep(pair.ptr, DepType::PRIVATE));
	}
	}

	if (data_deps == DataDeps::INCLUDE) {
	// Add data deps.
	for (const auto& pair : current_target->data_deps()) {
	work_queue.push_back(current_path);
	work_queue.back().push_back(TargetDep(pair.ptr, DepType::DATA));
	}
	}
	}
	}

	void DoSearch(const Target* from, const Target* to, const Options& options,
	Stats* stats) {
	BreadthFirstSearch(from, to, PrivateDeps::EXCLUDE, DataDeps::EXCLUDE,
	options.print_what, stats);
	if (!options.public_only) {
	// Check private deps.
	BreadthFirstSearch(from, to, PrivateDeps::INCLUDE,
	DataDeps::EXCLUDE, options.print_what, stats);
	if (options.with_data) {
	// Check data deps.
	BreadthFirstSearch(from, to, PrivateDeps::INCLUDE,
	DataDeps::INCLUDE, options.print_what, stats);
	}
	}
	}

	} // namespace

	const char kPath[] = "path";
	const char kPath_HelpShort[] =
	"path: Find paths between two targets.";
	const char kPath_Help[] =
	"gn path <out_dir> <target_one> <target_two>\n"
	"\n"
	" Finds paths of dependencies between two targets. Each unique path\n"
	" will be printed in one group, and groups will be separate by newlines.\n"
	" The two targets can appear in either order (paths will be found going\n"
	" in either direction).\n"
	"\n"
	" By default, a single path will be printed. If there is a path with\n"
	" only public dependencies, the shortest public path will be printed.\n"
	" Otherwise, the shortest path using either public or private\n"
	" dependencies will be printed. If --with-data is specified, data deps\n"
	" will also be considered. If there are multiple shortest paths, an\n"
	" arbitrary one will be selected.\n"
	"\n"
	"Interesting paths\n"
	"\n"
	" In a large project, there can be 100's of millions of unique paths\n"
	" between a very high level and a common low-level target. To make the\n"
	" output more useful (and terminate in a reasonable time), GN will not\n"
	" revisit sub-paths previously known to lead to the target.\n"
	"\n"
	"Options\n"
	"\n"
	" --all\n"
	" Prints all \"interesting\" paths found rather than just the first\n"
	" one. Public paths will be printed first in order of increasing\n"
	" length, followed by non-public paths in order of increasing length.\n"
	"\n"
	" --public\n"
	" Considers only public paths. Can't be used with --with-data.\n"
	"\n"
	" --with-data\n"
	" Additionally follows data deps. Without this flag, only public and\n"
	" private linked deps will be followed. Can't be used with --public.\n"
	"\n"
	"Example\n"
	"\n"
	" gn path out/Default //base //tools/gn\n";

	int RunPath(const std::vector<std::string>& args) {
	if (args.size() != 3) {
	Err(Location(), "You're holding it wrong.",
	"Usage: \"gn path <out_dir> <target_one> <target_two>\"")
	.PrintToStdout();
	return 1;
	}

	Setup* setup = new Setup;
	if (!setup->DoSetup(args[0], false))
	return 1;
	if (!setup->Run())
	return 1;

	const Target* target1 = ResolveTargetFromCommandLineString(setup, args[1]);
	if (!target1)
	return 1;
	const Target* target2 = ResolveTargetFromCommandLineString(setup, args[2]);
	if (!target2)
	return 1;

	Options options;
	options.print_what = base::CommandLine::ForCurrentProcess()->HasSwitch("all")
	? PrintWhat::ALL : PrintWhat::ONE;
	options.public_only =
	base::CommandLine::ForCurrentProcess()->HasSwitch("public");
	options.with_data =
	base::CommandLine::ForCurrentProcess()->HasSwitch("with-data");
	if (options.public_only && options.with_data) {
	Err(Location(), "Can't use --public with --with-data for 'gn path'.",
	"Your zealous over-use of arguments has inevitably resulted in an "
	"invalid\ncombination of flags.").PrintToStdout();
	return 1;
	}

	Stats stats;
	DoSearch(target1, target2, options, &stats);
	if (stats.total_paths() == 0) {
	// If we don't find a path going "forwards", try the reverse direction.
	// Deps can only go in one direction without having a cycle, which will
	// have caused a run failure above.
	DoSearch(target2, target1, options, &stats);
	}

	// This string is inserted in the results to annotate whether the result
	// is only public or includes data deps or not.
	const char* path_annotation = "";
	if (options.public_only)
	path_annotation = "public ";
	else if (!options.with_data)
	path_annotation = "non-data ";

	if (stats.total_paths() == 0) {
	// No results.
	OutputString(base::StringPrintf(
	"No %spaths found between these two targets.\n", path_annotation),
	DECORATION_YELLOW);
	} else if (stats.total_paths() == 1) {
	// Exactly one result.
	OutputString(base::StringPrintf("1 %spath found.", path_annotation),
	DECORATION_YELLOW);
	if (!options.public_only) {
	if (stats.public_paths)
	OutputString(" It is public.");
	else
	OutputString(" It is not public.");
	}
	OutputString("\n");
	} else {
	if (options.print_what == PrintWhat::ALL) {
	// Showing all paths when there are many.
	OutputString(base::StringPrintf("%d \"interesting\" %spaths found.",
	stats.total_paths(), path_annotation),
	DECORATION_YELLOW);
	if (!options.public_only) {
	OutputString(base::StringPrintf(" %d of them are public.",
	stats.public_paths));
	}
	OutputString("\n");
	} else {
	// Showing one path when there are many.
	OutputString(
	base::StringPrintf("Showing one of %d \"interesting\" %spaths.",
	stats.total_paths(), path_annotation),
	DECORATION_YELLOW);
	if (!options.public_only) {
	OutputString(base::StringPrintf(" %d of them are public.\n",
	stats.public_paths));
	}
	OutputString("Use --all to print all paths.\n");
	}
	}
	return 0;
	}

	} // namespace commands