Flatten the cpp jungle doing the nosuid checking.

p4raw-id: //depot/cfgperl@5933

diff --git a/perl.c b/perl.c
index 578fafc..6e02f40 100644 (file)
--- a/perl.c
+++ b/perl.c
@@ -2608,72 +2608,85 @@ S_fd_on_nosuid_fs(pTHX_ int fd)
  * an irrelevant filesystem while trying to reach the right one.
  */
 
-#   ifdef HAS_FSTATVFS
+#undef FD_ON_NOSUID_CHECK_OKAY  /* found the syscalls to do the check? */
+
+#   if !defined(FD_ON_NOSUID_CHECK_OKAY) && \
+        defined(HAS_FSTATVFS)
+#   define FD_ON_NOSUID_CHECK_OKAY
     struct statvfs stfs;
+
     check_okay = fstatvfs(fd, &stfs) == 0;
     on_nosuid  = check_okay && (stfs.f_flag  & ST_NOSUID);
-#   else
-#       ifdef PERL_MOUNT_NOSUID
-#           if defined(HAS_FSTATFS) && \
-              defined(HAS_STRUCT_STATFS) && \
-              defined(HAS_STRUCT_STATFS_F_FLAGS)
+#   endif /* fstatvfs */
+ 
+#   if !defined(FD_ON_NOSUID_CHECK_OKAY) && \
+        defined(PERL_MOUNT_NOSUID)     && \
+        defined(HAS_FSTATFS)           && \
+        defined(HAS_STRUCT_STATFS)     && \
+        defined(HAS_STRUCT_STATFS_F_FLAGS)
+#   define FD_ON_NOSUID_CHECK_OKAY
     struct statfs  stfs;
+
     check_okay = fstatfs(fd, &stfs)  == 0;
     on_nosuid  = check_okay && (stfs.f_flags & PERL_MOUNT_NOSUID);
-#           else
-#               if defined(HAS_FSTAT) && \
-                  defined(HAS_USTAT) && \
-                  defined(HAS_GETMNT) && \
-                  defined(HAS_STRUCT_FS_DATA) && \
-                  defined(NOSTAT_ONE)
+#   endif /* fstatfs */
+
+#   if !defined(FD_ON_NOSUID_CHECK_OKAY) && \
+        defined(PERL_MOUNT_NOSUID)     && \
+        defined(HAS_FSTAT)             && \
+        defined(HAS_USTAT)             && \
+        defined(HAS_GETMNT)            && \
+        defined(HAS_STRUCT_FS_DATA)    && \
+        defined(NOSTAT_ONE)
+#   define FD_ON_NOSUID_CHECK_OKAY
     struct stat fdst;
+
     if (fstat(fd, &fdst) == 0) {
-       struct ustat us;
-       if (ustat(fdst.st_dev, &us) == 0) {
-           struct fs_data fsd;
-           /* NOSTAT_ONE here because we're not examining fields which
-            * vary between that case and STAT_ONE. */
+        struct ustat us;
+        if (ustat(fdst.st_dev, &us) == 0) {
+            struct fs_data fsd;
+            /* NOSTAT_ONE here because we're not examining fields which
+             * vary between that case and STAT_ONE. */
             if (getmnt((int*)0, &fsd, (int)0, NOSTAT_ONE, us.f_fname) == 0) {
-               size_t cmplen = sizeof(us.f_fname);
-               if (sizeof(fsd.fd_req.path) < cmplen)
-                   cmplen = sizeof(fsd.fd_req.path);
-               if (strnEQ(fsd.fd_req.path, us.f_fname, cmplen) &&
-                   fdst.st_dev == fsd.fd_req.dev) {
-                       check_okay = 1;
-                       on_nosuid = fsd.fd_req.flags & PERL_MOUNT_NOSUID;
-                   }
-               }
-           }
-       }
-    }
-#               endif /* fstat+ustat+getmnt */
-#           endif /* fstatfs */
-#       else
-#           if defined(HAS_GETMNTENT) && \
-              defined(HAS_HASMNTOPT) && \
-              defined(MNTOPT_NOSUID)
-    FILE               *mtab = fopen("/etc/mtab", "r");
-    struct mntent      *entry;
-    struct stat                stb, fsb;
+                size_t cmplen = sizeof(us.f_fname);
+                if (sizeof(fsd.fd_req.path) < cmplen)
+                    cmplen = sizeof(fsd.fd_req.path);
+                if (strnEQ(fsd.fd_req.path, us.f_fname, cmplen) &&
+                    fdst.st_dev == fsd.fd_req.dev) {
+                        check_okay = 1;
+                        on_nosuid = fsd.fd_req.flags & PERL_MOUNT_NOSUID;
+                    }
+                }
+            }
+        }
+    }
+#   endif /* fstat+ustat+getmnt */
+
+#   if !defined(FD_ON_NOSUID_CHECK_OKAY) && \
+        defined(HAS_GETMNTENT)         && \
+        defined(HAS_HASMNTOPT)         && \
+        defined(MNTOPT_NOSUID)
+#   define FD_ON_NOSUID_CHECK_OKAY
+    FILE                *mtab = fopen("/etc/mtab", "r");
+    struct mntent       *entry;
+    struct stat         stb, fsb;
 
     if (mtab && (fstat(fd, &stb) == 0)) {
-       while (entry = getmntent(mtab)) {
-           if (stat(entry->mnt_dir, &fsb) == 0
-               && fsb.st_dev == stb.st_dev)
-           {
-               /* found the filesystem */
-               check_okay = 1;
-               if (hasmntopt(entry, MNTOPT_NOSUID))
-                   on_nosuid = 1;
-               break;
-           } /* A single fs may well fail its stat(). */
-       }
+        while (entry = getmntent(mtab)) {
+            if (stat(entry->mnt_dir, &fsb) == 0
+                && fsb.st_dev == stb.st_dev)
+            {
+                /* found the filesystem */
+                check_okay = 1;
+                if (hasmntopt(entry, MNTOPT_NOSUID))
+                    on_nosuid = 1;
+                break;
+            } /* A single fs may well fail its stat(). */
+        }
     }
     if (mtab)
-       fclose(mtab);
-#           endif /* getmntent+hasmntopt */
-#       endif /* PERL_MOUNT_NOSUID: fstatfs or fstat+ustat+statfs */
-#   endif /* statvfs */
+        fclose(mtab);
+#   endif /* getmntent+hasmntopt */
 
     if (!check_okay) 
        Perl_croak(aTHX_ "Can't check filesystem of script \"%s\" for nosuid", PL_origfilename);