Update scripts/gen_tests_elf_py.py to not use libdrgn/include/elf.h

libdrgn/include/elf.h no longer has the definitions that the script
needs. Update it to use the system elf.h and update tests/elf.py with one
new definition. Also make scripts/gen_elf_compat.py read elf.h in the
same way.

Signed-off-by: Omar Sandoval <osandov@osandov.com>

scripts/gen_elf_compat.py

@@ -77,28 +77,23 @@ MACROS = (
 
 def main() -> None:
     argparse.ArgumentParser(
-        description="Generate definitions missing from older versions of glibc for libdrgn/include/elf.h from /usr/include/elf.h"
+        description="Generate definitions missing from older versions of glibc for libdrgn/include/elf.h from elf.h"
     ).parse_args()
 
-    macros = {}
-
-    regex = re.compile(r"\s*#\s*define\s+(" + "|".join(MACROS) + r")\s+(.*)")
-    # Dump out just the macro definitions with gcc.
-    with subprocess.Popen(
-        [
-            "gcc",
-            "-dM",
-            "-E",
-            "/usr/include/elf.h",
-        ],
-        stdout=subprocess.PIPE,
+    contents = subprocess.check_output(
+        ["gcc", "-dD", "-E", "-"],
+        input="#include <elf.h>\n",
         universal_newlines=True,
-    ) as proc:
-        for line in proc.stdout:
-            match = regex.match(line)
-            if not match:
-                continue
-            macros[match.group(1)] = match.group(2)
+    )
+
+    macros = {
+        match.group(1): match.group(2)
+        for match in re.finditer(
+            r"^\s*#\s*define\s+(" + "|".join(MACROS) + r")\s+(.*)",
+            contents,
+            re.MULTILINE,
+        )
+    }
 
     print("// Generated by scripts/gen_elf_compat.py.")
     for macro in MACROS:

scripts/gen_tests_elf_py.py

@@ -3,19 +3,21 @@
 # SPDX-License-Identifier: LGPL-2.1-or-later
 
 import argparse
-from pathlib import Path
+import subprocess
 import re
 import sys
 
 
 def main() -> None:
     argparse.ArgumentParser(
-        description="Generate tests/elf.py from libdrgn/include/elf.h"
+        description="Generate tests/elf.py from elf.h"
     ).parse_args()
 
-    contents = Path("libdrgn/include/elf.h").read_text()
-    contents = re.sub(r"/\*.*?\*/", "", contents, flags=re.DOTALL)
-    contents = re.sub(r"\\\n", "", contents)
+    contents = subprocess.check_output(
+        ["gcc", "-dD", "-E", "-"],
+        input="#include <elf.h>\n",
+        universal_newlines=True,
+    )
 
     enums = {
         name: []

tests/elf.py

@@ -152,7 +152,8 @@ class SHT(enum.IntEnum):
     PREINIT_ARRAY = 0x10
     GROUP = 0x11
     SYMTAB_SHNDX = 0x12
-    NUM = 0x13
+    RELR = 0x13
+    NUM = 0x14
     LOOS = 0x60000000
     GNU_ATTRIBUTES = 0x6FFFFFF5
     GNU_HASH = 0x6FFFFFF6