1//===-- llvm-config.cpp - LLVM project configuration utility --------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This tool encapsulates information about an LLVM project configuration for
11// use by other project's build environments (to determine installed path,
12// available features, required libraries, etc.).
13//
14// Note that although this tool *may* be used by some parts of LLVM's build
15// itself (i.e., the Makefiles use it to compute required libraries when linking
16// tools), this tool is primarily designed to support external projects.
17//
18//===----------------------------------------------------------------------===//
19
20#include "llvm/ADT/STLExtras.h"
21#include "llvm/ADT/StringMap.h"
22#include "llvm/ADT/StringRef.h"
23#include "llvm/ADT/Triple.h"
24#include "llvm/ADT/Twine.h"
25#include "llvm/Config/config.h"
26#include "llvm/Config/llvm-config.h"
27#include "llvm/Support/FileSystem.h"
28#include "llvm/Support/Path.h"
29#include "llvm/Support/raw_ostream.h"
30#include <cstdlib>
31#include <set>
32#include <vector>
33
34using namespace llvm;
35
36// Include the build time variables we can report to the user. This is generated
37// at build time from the BuildVariables.inc.in file by the build system.
38#include "BuildVariables.inc"
39
40// Include the component table. This creates an array of struct
41// AvailableComponent entries, which record the component name, library name,
42// and required components for all of the available libraries.
43//
44// Not all components define a library, we also use "library groups" as a way to
45// create entries for pseudo groups like x86 or all-targets.
46#include "LibraryDependencies.inc"
47
48/// \brief Traverse a single component adding to the topological ordering in
49/// \arg RequiredLibs.
50///
51/// \param Name - The component to traverse.
52/// \param ComponentMap - A prebuilt map of component names to descriptors.
53/// \param VisitedComponents [in] [out] - The set of already visited components.
54/// \param RequiredLibs [out] - The ordered list of required libraries.
55static void VisitComponent(StringRef Name,
56                           const StringMap<AvailableComponent*> &ComponentMap,
57                           std::set<AvailableComponent*> &VisitedComponents,
58                           std::vector<StringRef> &RequiredLibs,
59                           bool IncludeNonInstalled) {
60  // Lookup the component.
61  AvailableComponent *AC = ComponentMap.lookup(Name);
62  assert(AC && "Invalid component name!");
63
64  // Add to the visited table.
65  if (!VisitedComponents.insert(AC).second) {
66    // We are done if the component has already been visited.
67    return;
68  }
69
70  // Only include non-installed components if requested.
71  if (!AC->IsInstalled && !IncludeNonInstalled)
72    return;
73
74  // Otherwise, visit all the dependencies.
75  for (unsigned i = 0; AC->RequiredLibraries[i]; ++i) {
76    VisitComponent(AC->RequiredLibraries[i], ComponentMap, VisitedComponents,
77                   RequiredLibs, IncludeNonInstalled);
78  }
79
80  // Add to the required library list.
81  if (AC->Library)
82    RequiredLibs.push_back(AC->Library);
83}
84
85/// \brief Compute the list of required libraries for a given list of
86/// components, in an order suitable for passing to a linker (that is, libraries
87/// appear prior to their dependencies).
88///
89/// \param Components - The names of the components to find libraries for.
90/// \param RequiredLibs [out] - On return, the ordered list of libraries that
91/// are required to link the given components.
92/// \param IncludeNonInstalled - Whether non-installed components should be
93/// reported.
94void ComputeLibsForComponents(const std::vector<StringRef> &Components,
95                              std::vector<StringRef> &RequiredLibs,
96                              bool IncludeNonInstalled) {
97  std::set<AvailableComponent*> VisitedComponents;
98
99  // Build a map of component names to information.
100  StringMap<AvailableComponent*> ComponentMap;
101  for (unsigned i = 0; i != array_lengthof(AvailableComponents); ++i) {
102    AvailableComponent *AC = &AvailableComponents[i];
103    ComponentMap[AC->Name] = AC;
104  }
105
106  // Visit the components.
107  for (unsigned i = 0, e = Components.size(); i != e; ++i) {
108    // Users are allowed to provide mixed case component names.
109    std::string ComponentLower = Components[i].lower();
110
111    // Validate that the user supplied a valid component name.
112    if (!ComponentMap.count(ComponentLower)) {
113      llvm::errs() << "llvm-config: unknown component name: " << Components[i]
114                   << "\n";
115      exit(1);
116    }
117
118    VisitComponent(ComponentLower, ComponentMap, VisitedComponents,
119                   RequiredLibs, IncludeNonInstalled);
120  }
121
122  // The list is now ordered with leafs first, we want the libraries to printed
123  // in the reverse order of dependency.
124  std::reverse(RequiredLibs.begin(), RequiredLibs.end());
125}
126
127/* *** */
128
129void usage() {
130  errs() << "\
131usage: llvm-config <OPTION>... [<COMPONENT>...]\n\
132\n\
133Get various configuration information needed to compile programs which use\n\
134LLVM.  Typically called from 'configure' scripts.  Examples:\n\
135  llvm-config --cxxflags\n\
136  llvm-config --ldflags\n\
137  llvm-config --libs engine bcreader scalaropts\n\
138\n\
139Options:\n\
140  --version         Print LLVM version.\n\
141  --prefix          Print the installation prefix.\n\
142  --src-root        Print the source root LLVM was built from.\n\
143  --obj-root        Print the object root used to build LLVM.\n\
144  --bindir          Directory containing LLVM executables.\n\
145  --includedir      Directory containing LLVM headers.\n\
146  --libdir          Directory containing LLVM libraries.\n\
147  --cppflags        C preprocessor flags for files that include LLVM headers.\n\
148  --cflags          C compiler flags for files that include LLVM headers.\n\
149  --cxxflags        C++ compiler flags for files that include LLVM headers.\n\
150  --ldflags         Print Linker flags.\n\
151  --system-libs     System Libraries needed to link against LLVM components.\n\
152  --libs            Libraries needed to link against LLVM components.\n\
153  --libnames        Bare library names for in-tree builds.\n\
154  --libfiles        Fully qualified library filenames for makefile depends.\n\
155  --components      List of all possible components.\n\
156  --targets-built   List of all targets currently built.\n\
157  --host-target     Target triple used to configure LLVM.\n\
158  --build-mode      Print build mode of LLVM tree (e.g. Debug or Release).\n\
159  --assertion-mode  Print assertion mode of LLVM tree (ON or OFF).\n\
160Typical components:\n\
161  all               All LLVM libraries (default).\n\
162  engine            Either a native JIT or a bitcode interpreter.\n";
163  exit(1);
164}
165
166/// \brief Compute the path to the main executable.
167std::string GetExecutablePath(const char *Argv0) {
168  // This just needs to be some symbol in the binary; C++ doesn't
169  // allow taking the address of ::main however.
170  void *P = (void*) (intptr_t) GetExecutablePath;
171  return llvm::sys::fs::getMainExecutable(Argv0, P);
172}
173
174int main(int argc, char **argv) {
175  std::vector<StringRef> Components;
176  bool PrintLibs = false, PrintLibNames = false, PrintLibFiles = false;
177  bool PrintSystemLibs = false;
178  bool HasAnyOption = false;
179
180  // llvm-config is designed to support being run both from a development tree
181  // and from an installed path. We try and auto-detect which case we are in so
182  // that we can report the correct information when run from a development
183  // tree.
184  bool IsInDevelopmentTree;
185  enum { MakefileStyle, CMakeStyle, CMakeBuildModeStyle } DevelopmentTreeLayout;
186  llvm::SmallString<256> CurrentPath(GetExecutablePath(argv[0]));
187  std::string CurrentExecPrefix;
188  std::string ActiveObjRoot;
189
190  // If CMAKE_CFG_INTDIR is given, honor it as build mode.
191  char const *build_mode = LLVM_BUILDMODE;
192#if defined(CMAKE_CFG_INTDIR)
193  if (!(CMAKE_CFG_INTDIR[0] == '.' && CMAKE_CFG_INTDIR[1] == '\0'))
194    build_mode = CMAKE_CFG_INTDIR;
195#endif
196
197  // Create an absolute path, and pop up one directory (we expect to be inside a
198  // bin dir).
199  sys::fs::make_absolute(CurrentPath);
200  CurrentExecPrefix = sys::path::parent_path(
201    sys::path::parent_path(CurrentPath)).str();
202
203  // Check to see if we are inside a development tree by comparing to possible
204  // locations (prefix style or CMake style).
205  if (sys::fs::equivalent(CurrentExecPrefix,
206                          Twine(LLVM_OBJ_ROOT) + "/" + build_mode)) {
207    IsInDevelopmentTree = true;
208    DevelopmentTreeLayout = MakefileStyle;
209
210    // If we are in a development tree, then check if we are in a BuildTools
211    // directory. This indicates we are built for the build triple, but we
212    // always want to provide information for the host triple.
213    if (sys::path::filename(LLVM_OBJ_ROOT) == "BuildTools") {
214      ActiveObjRoot = sys::path::parent_path(LLVM_OBJ_ROOT);
215    } else {
216      ActiveObjRoot = LLVM_OBJ_ROOT;
217    }
218  } else if (sys::fs::equivalent(CurrentExecPrefix, LLVM_OBJ_ROOT)) {
219    IsInDevelopmentTree = true;
220    DevelopmentTreeLayout = CMakeStyle;
221    ActiveObjRoot = LLVM_OBJ_ROOT;
222  } else if (sys::fs::equivalent(CurrentExecPrefix,
223                                 Twine(LLVM_OBJ_ROOT) + "/bin")) {
224    IsInDevelopmentTree = true;
225    DevelopmentTreeLayout = CMakeBuildModeStyle;
226    ActiveObjRoot = LLVM_OBJ_ROOT;
227  } else {
228    IsInDevelopmentTree = false;
229    DevelopmentTreeLayout = MakefileStyle; // Initialized to avoid warnings.
230  }
231
232  // Compute various directory locations based on the derived location
233  // information.
234  std::string ActivePrefix, ActiveBinDir, ActiveIncludeDir, ActiveLibDir;
235  std::string ActiveIncludeOption;
236  if (IsInDevelopmentTree) {
237    ActiveIncludeDir = std::string(LLVM_SRC_ROOT) + "/include";
238    ActivePrefix = CurrentExecPrefix;
239
240    // CMake organizes the products differently than a normal prefix style
241    // layout.
242    switch (DevelopmentTreeLayout) {
243    case MakefileStyle:
244      ActivePrefix = ActiveObjRoot;
245      ActiveBinDir = ActiveObjRoot + "/" + build_mode + "/bin";
246      ActiveLibDir = ActiveObjRoot + "/" + build_mode + "/lib";
247      break;
248    case CMakeStyle:
249      ActiveBinDir = ActiveObjRoot + "/bin";
250      ActiveLibDir = ActiveObjRoot + "/lib";
251      break;
252    case CMakeBuildModeStyle:
253      ActivePrefix = ActiveObjRoot;
254      ActiveBinDir = ActiveObjRoot + "/bin/" + build_mode;
255      ActiveLibDir = ActiveObjRoot + "/lib/" + build_mode;
256      break;
257    }
258
259    // We need to include files from both the source and object trees.
260    ActiveIncludeOption = ("-I" + ActiveIncludeDir + " " +
261                           "-I" + ActiveObjRoot + "/include");
262  } else {
263    ActivePrefix = CurrentExecPrefix;
264    ActiveIncludeDir = ActivePrefix + "/include";
265    ActiveBinDir = ActivePrefix + "/bin";
266    ActiveLibDir = ActivePrefix + "/lib";
267    ActiveIncludeOption = "-I" + ActiveIncludeDir;
268  }
269
270  raw_ostream &OS = outs();
271  for (int i = 1; i != argc; ++i) {
272    StringRef Arg = argv[i];
273
274    if (Arg.startswith("-")) {
275      HasAnyOption = true;
276      if (Arg == "--version") {
277        OS << PACKAGE_VERSION << '\n';
278      } else if (Arg == "--prefix") {
279        OS << ActivePrefix << '\n';
280      } else if (Arg == "--bindir") {
281        OS << ActiveBinDir << '\n';
282      } else if (Arg == "--includedir") {
283        OS << ActiveIncludeDir << '\n';
284      } else if (Arg == "--libdir") {
285        OS << ActiveLibDir << '\n';
286      } else if (Arg == "--cppflags") {
287        OS << ActiveIncludeOption << ' ' << LLVM_CPPFLAGS << '\n';
288      } else if (Arg == "--cflags") {
289        OS << ActiveIncludeOption << ' ' << LLVM_CFLAGS << '\n';
290      } else if (Arg == "--cxxflags") {
291        OS << ActiveIncludeOption << ' ' << LLVM_CXXFLAGS << '\n';
292      } else if (Arg == "--ldflags") {
293        OS << "-L" << ActiveLibDir << ' ' << LLVM_LDFLAGS << '\n';
294      } else if (Arg == "--system-libs") {
295        PrintSystemLibs = true;
296      } else if (Arg == "--libs") {
297        PrintLibs = true;
298      } else if (Arg == "--libnames") {
299        PrintLibNames = true;
300      } else if (Arg == "--libfiles") {
301        PrintLibFiles = true;
302      } else if (Arg == "--components") {
303        for (unsigned j = 0; j != array_lengthof(AvailableComponents); ++j) {
304          // Only include non-installed components when in a development tree.
305          if (!AvailableComponents[j].IsInstalled && !IsInDevelopmentTree)
306            continue;
307
308          OS << ' ';
309          OS << AvailableComponents[j].Name;
310        }
311        OS << '\n';
312      } else if (Arg == "--targets-built") {
313        OS << LLVM_TARGETS_BUILT << '\n';
314      } else if (Arg == "--host-target") {
315        OS << Triple::normalize(LLVM_DEFAULT_TARGET_TRIPLE) << '\n';
316      } else if (Arg == "--build-mode") {
317        OS << build_mode << '\n';
318      } else if (Arg == "--assertion-mode") {
319#if defined(NDEBUG)
320        OS << "OFF\n";
321#else
322        OS << "ON\n";
323#endif
324      } else if (Arg == "--obj-root") {
325        OS << ActivePrefix << '\n';
326      } else if (Arg == "--src-root") {
327        OS << LLVM_SRC_ROOT << '\n';
328      } else {
329        usage();
330      }
331    } else {
332      Components.push_back(Arg);
333    }
334  }
335
336  if (!HasAnyOption)
337    usage();
338
339  if (PrintLibs || PrintLibNames || PrintLibFiles || PrintSystemLibs) {
340    // If no components were specified, default to "all".
341    if (Components.empty())
342      Components.push_back("all");
343
344    // Construct the list of all the required libraries.
345    std::vector<StringRef> RequiredLibs;
346    ComputeLibsForComponents(Components, RequiredLibs,
347                             /*IncludeNonInstalled=*/IsInDevelopmentTree);
348
349    if (PrintLibs || PrintLibNames || PrintLibFiles) {
350      for (unsigned i = 0, e = RequiredLibs.size(); i != e; ++i) {
351        StringRef Lib = RequiredLibs[i];
352        if (i)
353          OS << ' ';
354
355        if (PrintLibNames) {
356          OS << Lib;
357        } else if (PrintLibFiles) {
358          OS << ActiveLibDir << '/' << Lib;
359        } else if (PrintLibs) {
360          // If this is a typical library name, include it using -l.
361          if (Lib.startswith("lib") && Lib.endswith(".a")) {
362            OS << "-l" << Lib.slice(3, Lib.size()-2);
363            continue;
364          }
365
366          // Otherwise, print the full path.
367          OS << ActiveLibDir << '/' << Lib;
368        }
369      }
370      OS << '\n';
371    }
372
373    // Print SYSTEM_LIBS after --libs.
374    // FIXME: Each LLVM component may have its dependent system libs.
375    if (PrintSystemLibs)
376      OS << LLVM_SYSTEM_LIBS << '\n';
377  } else if (!Components.empty()) {
378    errs() << "llvm-config: error: components given, but unused\n\n";
379    usage();
380  }
381
382  return 0;
383}
384