Subject: Also wrap the "stat" library call
Author: Christoph Biedl <debian.axhn@manchmal.in-ulm.de>
Date: 2021-12-20
Bug-Debian: https://bugs.debian.org/1001961
Forwarded: Yes

    Seems changes in glibc 2.33 caused the stat() function to be mapped
    into a stat() library call instead of __xstat() as it used to be.

    However, fakeroot does not wrap this, causing files to be reported
    with the real owner, not 0 as expected.

    The fix for this got a bit ugly as the abstraction in configure.ac
    would not allow wrapping both "stat" and "__xstat". So enhance the
    search list capabilities with an optional symbol how the wrapped
    function is named internally. Also hack the parser so "stat" gets
    actually probed and not mistaken for __xstat.

    Using "realstat" as a symbol is not the best choice as it might be
    confusing, but "statstat" seemed even worse.

--- a/configure.ac
+++ b/configure.ac
@@ -353,9 +353,13 @@
 
 :>fakerootconfig.h.tmp
 
-for SEARCH in %stat f%stat l%stat f%statat %stat64 f%stat64 l%stat64 f%statat64 %mknod %mknodat; do
-  FUNC=`echo $SEARCH|sed -e 's/.*%//'`
+for SEARCH in %stat s%tat@realstat f%stat l%stat f%statat %stat64 f%stat64 l%stat64 f%statat64 %mknod %mknodat; do
+  FUNC=`echo $SEARCH|sed -e 's/.*%// ; s/@.*//'`
   PRE=`echo $SEARCH|sed -e 's/%.*//'`
+  SYMBOL=`echo $SEARCH|sed -e 's/.*@//'`
+  if test "$SYMBOL" = "$SEARCH" ; then
+    SYMBOL="${PRE}${FUNC}"
+  fi
   FOUND=
   for WRAPPED in __${PRE}x${FUNC} _${PRE}x${FUNC} __${PRE}${FUNC}13 ${PRE}${FUNC}; do
     AC_CHECK_FUNCS($WRAPPED,FOUND=$WRAPPED)
@@ -366,8 +370,8 @@
 dnl  for WRAPPED in _${PRE}${FUNC}; do
 dnl    FOUND=$WRAPPED
     if test -n "$FOUND"; then
-      PF=[`echo ${PRE}${FUNC}| tr '[a-z]' '[A-Z]'`]
-      DEFINE_WRAP=[`echo wrap_${PRE}${FUNC}| tr '[a-z]' '[A-Z]'`]
+      PF=[`echo $SYMBOL | tr '[a-z]' '[A-Z]'`]
+      DEFINE_WRAP=[`echo wrap_${SYMBOL}| tr '[a-z]' '[A-Z]'`]
       DEFINE_NEXT=[`echo wrap_${FOUND}| tr '[a-z]' '[A-Z]'`]
       DEFINE_ARG=[`echo wrap_${FOUND}| tr '[a-z]' '[A-Z]'`]
       AC_DEFINE_UNQUOTED(WRAP_${PF}, $FOUND)
@@ -509,6 +513,12 @@
 #define TMP_STAT  __astat
 #define NEXT_STAT_NOARG  next___astat
 
+#define WRAP_REALSTAT  __astat
+#define WRAP_REALSTAT_QUOTE  __astat
+#define WRAP_REALSTAT_RAW  __astat
+#define TMP_REALSTAT  __astat
+#define NEXT_REALSTAT_NOARG  next___astat
+
 #define WRAP_LSTAT_QUOTE  __astat
 #define WRAP_LSTAT  __astat
 #define WRAP_LSTAT_RAW  __astat