lldb/bindings/python/get-python-config.py

   1 #!/usr/bin/env python3
   2
   3 import os
   4 import sys
   5 import argparse
   6 import sysconfig
   7
   8
   9 def relpath_nodots(path, base):
  10     rel = os.path.normpath(os.path.relpath(path, base))
  11     assert not os.path.isabs(rel)
  12     parts = rel.split(os.path.sep)
  13     if parts and parts[0] == "..":
  14         raise ValueError(f"{path} is not under {base}")
  15     return rel
  16
  17
  18 def main():
  19     parser = argparse.ArgumentParser(description="extract cmake variables from python")
  20     parser.add_argument("variable_name")
  21     args = parser.parse_args()
  22     if args.variable_name == "LLDB_PYTHON_RELATIVE_PATH":
  23         # LLDB_PYTHON_RELATIVE_PATH is the relative path from lldb's prefix
  24         # to where lldb's python libraries will be installed.
  25         #
  26         # The way we're going to compute this is to take the relative path from
  27         # PYTHON'S prefix to where python libraries are supposed to be
  28         # installed.
  29         #
  30         # The result is if LLDB and python are give the same prefix, then
  31         # lldb's python lib will be put in the correct place for python to find it.
  32         # If not, you'll have to use lldb -P or lldb -print-script-interpreter-info
  33         # to figure out where it is.
  34         try:
  35             print(relpath_nodots(sysconfig.get_path("platlib"), sys.prefix))
  36         except ValueError:
  37             # Try to fall back to something reasonable if sysconfig's platlib
  38             # is outside of sys.prefix
  39             if os.name == "posix":
  40                 print("lib/python%d.%d/site-packages" % sys.version_info[:2])
  41             elif os.name == "nt":
  42                 print("Lib\\site-packages")
  43             else:
  44                 raise
  45     elif args.variable_name == "LLDB_PYTHON_EXE_RELATIVE_PATH":
  46         tried = list()
  47         exe = sys.executable
  48         prefix = os.path.realpath(sys.prefix)
  49         while True:
  50             try:
  51                 print(relpath_nodots(exe, prefix))
  52                 break
  53             except ValueError:
  54                 tried.append(exe)
  55                 # Retry if the executable is symlinked or similar.
  56                 # This is roughly equal to os.path.islink, except it also works for junctions on Windows.
  57                 if os.path.realpath(exe) != exe:
  58                     exe = os.path.realpath(exe)
  59                     continue
  60                 else:
  61                     print(
  62                         "Could not find a relative path to sys.executable under sys.prefix",
  63                         file=sys.stderr,
  64                     )
  65                     for e in tried:
  66                         print("tried:", e, file=sys.stderr)
  67                     print("realpath(sys.prefix):", prefix, file=sys.stderr)
  68                     print("sys.prefix:", sys.prefix, file=sys.stderr)
  69                     sys.exit(1)
  70     elif args.variable_name == "LLDB_PYTHON_EXT_SUFFIX":
  71         print(sysconfig.get_config_var("EXT_SUFFIX"))
  72     else:
  73         parser.error(f"unknown variable {args.variable_name}")
  74
  75
  76 if __name__ == "__main__":
  77     main()