python/makefile.py

   1 #!/usr/bin/python3
   2 #
   3 # FRR extended automake/Makefile functionality helper
   4 #
   5 # This script is executed on/after generating Makefile to add some pieces for
   6 # clippy.
   7
   8 import sys
   9 import os
  10 import subprocess
  11 import re
  12 import argparse
  13 from string import Template
  14 from makevars import MakeReVars
  15
  16 argp = argparse.ArgumentParser(description="FRR Makefile extensions")
  17 argp.add_argument(
  18     "--dev-build",
  19     action="store_const",
  20     const=True,
  21     help="run additional developer checks",
  22 )
  23 args = argp.parse_args()
  24
  25 with open("Makefile", "r") as fd:
  26     before = fd.read()
  27
  28 mv = MakeReVars(before)
  29
  30 clippy_scan = mv["clippy_scan"].strip().split()
  31 for clippy_file in clippy_scan:
  32     assert clippy_file.endswith(".c")
  33
  34 xref_targets = []
  35 for varname in [
  36     "bin_PROGRAMS",
  37     "sbin_PROGRAMS",
  38     "lib_LTLIBRARIES",
  39     "module_LTLIBRARIES",
  40 ]:
  41     xref_targets.extend(mv[varname].strip().split())
  42
  43 # check for files using clippy but not listed in clippy_scan
  44 if args.dev_build:
  45     basepath = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))
  46     if os.path.exists(os.path.join(basepath, ".git")):
  47         clippy_ref = subprocess.check_output(
  48             [
  49                 "git",
  50                 "-C",
  51                 basepath,
  52                 "grep",
  53                 "-l",
  54                 "-P",
  55                 "^#\s*include.*_clippy.c",
  56                 "--",
  57                 "**.c",
  58             ]
  59         ).decode("US-ASCII")
  60
  61         clippy_ref = set(clippy_ref.splitlines())
  62         missing = clippy_ref - set(clippy_scan)
  63
  64         if len(missing) > 0:
  65             sys.stderr.write(
  66                 'error: files seem to be using clippy, but not listed in "clippy_scan" in subdir.am:\n\t%s\n'
  67                 % ("\n\t".join(sorted(missing)))
  68             )
  69             sys.exit(1)
  70
  71 # this additional-dependency rule is stuck onto all compile targets that
  72 # compile a file which uses clippy-generated input, so it has a dependency to
  73 # make that first.
  74 clippydep = Template(
  75     """
  76 ${clippybase}.$$(OBJEXT): ${clippybase}_clippy.c
  77 ${clippybase}.lo: ${clippybase}_clippy.c
  78 ${clippybase}_clippy.c: $$(CLIPPY_DEPS)"""
  79 )
  80
  81 # this one is used when one .c file is built multiple times with different
  82 # CFLAGS
  83 clippyauxdep = Template(
  84     """# clippy{
  85 # auxiliary clippy target
  86 ${target}: ${clippybase}_clippy.c
  87 # }clippy"""
  88 )
  89
  90 lines = before.splitlines()
  91 autoderp = "#AUTODERP# "
  92 out_lines = []
  93 bcdeps = []
  94 make_rule_re = re.compile("^([^:\s]+):\s*([^:\s]+)\s*($|\n)")
  95
  96 while lines:
  97     line = lines.pop(0)
  98     if line.startswith(autoderp):
  99         line = line[len(autoderp) :]
 100
 101     # allow rerunning on already-clippified Makefile
 102     if line == "# clippy{":
 103         while lines:
 104             line = lines.pop(0)
 105             if line == "# }clippy":
 106                 break
 107         continue
 108
 109     if line.startswith("#"):
 110         out_lines.append(line)
 111         continue
 112
 113     full_line = line
 114     full_lines = lines[:]
 115     while full_line.endswith("\\"):
 116         full_line = full_line[:-1] + full_lines.pop(0)
 117
 118     m = make_rule_re.match(full_line)
 119     if m is None:
 120         out_lines.append(line)
 121         continue
 122
 123     line, lines = full_line, full_lines
 124
 125     target, dep = m.group(1), m.group(2)
 126
 127     filename = os.path.basename(target)
 128     if "-" in filename:
 129         # dashes in output filename = building same .c with different CFLAGS
 130         am_name, _ = filename.split("-", 1)
 131         am_name = os.path.join(os.path.dirname(target), am_name)
 132         am_name = am_name.replace("/", "_")
 133         extraflags = " $(%s_CFLAGS)" % (am_name,)
 134     else:
 135         # this path isn't really triggered because automake is using a generic
 136         # .c => .o rule unless CFLAGS are customized for a target
 137         extraflags = ""
 138
 139     if target.endswith(".lo") or target.endswith(".o"):
 140         if not dep.endswith(".h"):
 141             # LLVM bitcode targets for analysis tools
 142             bcdeps.append("%s.bc: %s" % (target, target))
 143             bcdeps.append(
 144                 "\t$(AM_V_LLVM_BC)$(COMPILE)%s -emit-llvm -c -o $@ %s"
 145                 % (extraflags, dep)
 146             )
 147     if m.group(2) in clippy_scan:
 148         # again - this is only hit for targets with custom CFLAGS, because
 149         # automake uses a generic .c -> .o rule for standard CFLAGS
 150         out_lines.append(
 151             clippyauxdep.substitute(target=m.group(1), clippybase=m.group(2)[:-2])
 152         )
 153
 154     out_lines.append(line)
 155
 156 # now, cover all the .c files that don't have special build rules
 157 out_lines.append("# clippy{\n# main clippy targets")
 158 for clippy_file in clippy_scan:
 159     out_lines.append(clippydep.substitute(clippybase=clippy_file[:-2]))
 160
 161 # combine daemon .xref files into frr.xref
 162 out_lines.append("")
 163 out_lines.append(
 164     "xrefs = %s" % (" ".join(["%s.xref" % target for target in xref_targets]))
 165 )
 166 out_lines.append("frr.xref: $(xrefs)")
 167 out_lines.append("")
 168
 169 # analog but slower way to get the same frr.xref
 170 # frr.xref: $(bin_PROGRAMS) $(sbin_PROGRAMS) $(lib_LTLIBRARIES) $(module_LTLIBRARIES)
 171 #       $(AM_V_XRELFO) $(CLIPPY) $(top_srcdir)/python/xrelfo.py -o $@ $^
 172
 173 # LLVM bitcode link targets creating a .bc file for whole daemon or lib
 174 out_lines.append("")
 175 out_lines.extend(bcdeps)
 176 out_lines.append("")
 177 bc_targets = []
 178 for varname in [
 179     "bin_PROGRAMS",
 180     "sbin_PROGRAMS",
 181     "lib_LTLIBRARIES",
 182     "module_LTLIBRARIES",
 183     "noinst_LIBRARIES",
 184 ]:
 185     bc_targets.extend(mv[varname].strip().split())
 186 for target in bc_targets:
 187     amtgt = target.replace("/", "_").replace(".", "_").replace("-", "_")
 188     objs = mv[amtgt + "_OBJECTS"].strip().split()
 189     objs = [obj + ".bc" for obj in objs]
 190     deps = mv.get(amtgt + "_DEPENDENCIES", "").strip().split()
 191     deps = [d + ".bc" for d in deps if d.endswith(".a")]
 192     objs.extend(deps)
 193     out_lines.append("%s.bc: %s" % (target, " ".join(objs)))
 194     out_lines.append("\t$(AM_V_LLVM_LD)$(LLVM_LINK) -o $@ $^")
 195     out_lines.append("")
 196
 197 out_lines.append("# }clippy")
 198 out_lines.append("")
 199
 200 after = "\n".join(out_lines)
 201 if after == before:
 202     sys.exit(0)
 203
 204 with open("Makefile.pyout", "w") as fd:
 205     fd.write(after)
 206 os.rename("Makefile.pyout", "Makefile")