Don't do /proc file hack if system doesn't support /proc.

Assume system supports /proc only if statfs & PROC_SUPER_MAGIC exist.

ch.c

@@ -26,7 +26,7 @@ extern dev_t curr_dev;
 extern ino_t curr_ino;
 #endif
 
-#if HAVE_STATFS
+#if HAVE_PROCFS
 #include <sys/statfs.h>
 #endif
 
@@ -688,30 +688,6 @@ ch_setbufspace(bufspace)
  }
 }
 
-/*
- */
- static int
-trust_size(file, fsize)
- int file;
- POSITION fsize;
-{
- if (fsize != 0)
- {
- /* Nontrustable files always say their size is 0, so this isn't one. */
- return 1;
- }
-#if HAVE_STATFS
- /* Cannot trust procfs files. */
- struct statfs st;
- if (fstatfs(file, &st) == 0)
- return (st.f_type != PROC_SUPER_MAGIC);
-#else
- (void) file;
-#endif
- /* If we can't tell the file type, be safe and say it's not trustable. */
- return 0;
-}
-
 /*
  * Flush (discard) any saved file state, including buffer contents.
  */
@@ -753,17 +729,24 @@ ch_flush(VOID_PARAM)
  ch_block = 0; /* ch_fpos / LBUFSIZE; */
  ch_offset = 0; /* ch_fpos % LBUFSIZE; */
 
-#if 1
+#if HAVE_PROCFS
  /*
  * This is a kludge to workaround a Linux kernel bug: files in
  * /proc have a size of 0 according to fstat() but have readable 
  * data. They are sometimes, but not always, seekable.
  * Force them to be non-seekable here.
  */
- if (!trust_size(ch_file, ch_fsize))
+ if (ch_fsize == 0)
  {
- ch_fsize = NULL_POSITION;
- ch_flags &= ~CH_CANSEEK;
+ struct statfs st;
+ if (fstatfs(ch_file, &st) == 0)
+ {
+ if (st.f_type == PROC_SUPER_MAGIC)
+ {
+ ch_fsize = NULL_POSITION;
+ ch_flags &= ~CH_CANSEEK;
+ }
+ }
  }
 #endif
 

configure.ac

@@ -217,8 +217,8 @@ AH_TEMPLATE([HAVE_CONST],
  [Define HAVE_CONST if your compiler supports the "const" modifier.])
 AH_TEMPLATE([HAVE_STAT_INO],
  [Define HAVE_STAT_INO if your struct stat has st_ino and st_dev.])
-AH_TEMPLATE([HAVE_STATFS],
- [Define HAVE_STATFS if have have fstatfs with f_type.])
+AH_TEMPLATE([HAVE_PROCFS],
+ [Define HAVE_PROCFS if have have fstatfs with f_type and PROC_SUPER_MAGIC.])
 AH_TEMPLATE([HAVE_TIME_T],
  [Define HAVE_TIME_T if your system supports the "time_t" type.])
 AH_TEMPLATE([HAVE_STRERROR],
@@ -268,10 +268,10 @@ AC_TRY_COMPILE([#include <sys/types.h>
 #include <sys/stat.h>],
  [struct stat s; dev_t dev = s.st_dev; ino_t ino = s.st_ino;],
  [AC_MSG_RESULT(yes); AC_DEFINE(HAVE_STAT_INO)], [AC_MSG_RESULT(no)])
-AC_MSG_CHECKING(for statfs)
+AC_MSG_CHECKING(for procfs)
 AC_TRY_COMPILE([#include <sys/statfs.h>],
  [struct statfs s; s.f_type = PROC_SUPER_MAGIC; (void) fstatfs(0,&s); ],
- [AC_MSG_RESULT(yes); AC_DEFINE(HAVE_STATFS)], [AC_MSG_RESULT(no)])
+ [AC_MSG_RESULT(yes); AC_DEFINE(HAVE_PROCFS)], [AC_MSG_RESULT(no)])
 
 # Checks for ANSI function prototypes.
 AC_MSG_CHECKING(for ANSI function prototypes)