[PATCH] implement a few constants for sysconf(3)

[Andy Shevchenko <andy.shevchenko%gmail.com@localhost>]

Implement a set of the constants which expandes sysconf(3) functionality.
getconf(1) has been updated accordingly.

Affected constans are:
        _SC_HOST_NAME_MAX
        _SC_PASS_MAX
        _SC_REGEXP
        _SC_SHELL
        _SC_SYMLOOP_MAX

Additionally get rid of useless code.
---
 lib/libc/gen/sysconf.3    |   14 ++++++++++++++
 lib/libc/gen/sysconf.c    |   15 +++++++++++++--
 sys/sys/unistd.h          |   21 +++++++++++++++++++++
 usr.bin/getconf/getconf.c |    7 +++++++
 4 files changed, 55 insertions(+), 2 deletions(-)

diff --git a/lib/libc/gen/sysconf.3 b/lib/libc/gen/sysconf.3
index 0e18c8f..04c9358 100644
--- a/lib/libc/gen/sysconf.3
+++ b/lib/libc/gen/sysconf.3
@@ -87,6 +87,8 @@ The number of clock ticks per second.
 .It Li _SC_FSYNC
 Return 1 if the File Synchronization Option is available on this system,
 otherwise \-1.
+.It Li _SC_HOST_NAME_MAX
+The maximum size of a hostname, including NULL.
 .It Li _SC_IOV_MAX
 The maximum number of
 .Va iovec
@@ -127,6 +129,8 @@ The maximum number of supplemental groups.
 The maximum number of open files per process.
 .It Li _SC_PAGESIZE
 The size of a system page in bytes.
+.It Li _SC_PASS_MAX
+The maximum length of the password, not counting NULL.
 .It Li _SC_READER_WRITER_LOCKS
 The version of
 .St -p1003.1
@@ -134,6 +138,10 @@ and its
 Read-Write Locks
 option to which the system attempts to conform,
 otherwise \-1.
+.It Li _SC_REGEXP
+Return 1 if
+.Tn POSIX
+regular expressions are available on this system, otherwise \-1.
 .It Li _SC_SEMAPHORES
 The version of
 .St -p1003.1
@@ -147,6 +155,10 @@ Semaphores
 option depends on the
 .Li P1003_1B_SEMAPHORE
 kernel option.
+.It Li _SC_SHELL
+Return 1 if
+.Tn POSIX
+shell is available on this system, otherwise \-1.
 .It Li _SC_SPIN_LOCKS
 The version of
 .St -p1003.1
@@ -157,6 +169,8 @@ otherwise \-1.
 .It Li _SC_STREAM_MAX
 The minimum maximum number of streams that a process may have open
 at any one time.
+.It Li _SC_SYMLOOP_MAX
+The maximum number of symbolic links that may be expanded in a path name.
 .It Li _SC_SYNCHRONIZED_IO
 Return 1 if the Synchronized I/O Option is available on this system,
 otherwise \-1.
diff --git a/lib/libc/gen/sysconf.c b/lib/libc/gen/sysconf.c
index cd3ed56..dca8f35 100644
--- a/lib/libc/gen/sysconf.c
+++ b/lib/libc/gen/sysconf.c
@@ -52,6 +52,7 @@ __RCSID("$NetBSD$");
 #include <time.h>
 #include <unistd.h>
 #include <paths.h>
+#include <pwd.h>
 
 #ifdef __weak_alias
 __weak_alias(sysconf,__sysconf)
@@ -336,13 +337,23 @@ sysconf(int name)
        case _SC_GETPW_R_SIZE_MAX:
                return _GETPW_R_SIZE_MAX;
 
+/* Unsorted */
+       case _SC_HOST_NAME_MAX:
+               return MAXHOSTNAMELEN;
+       case _SC_PASS_MAX:
+               return _PASSWORD_LEN;
+       case _SC_REGEXP:
+               return _POSIX_REGEXP;
+       case _SC_SHELL:
+               return _POSIX_SHELL;
+       case _SC_SYMLOOP_MAX:
+               return MAXSYMLINKS;
+
 yesno:         if (sysctl(mib, mib_len, &value, &len, NULL, 0) == -1)
                        return (-1);
                if (value == 0)
                        return (-1);
                return (value);
-               /*NOTREACHED*/
-               break;
 
 /* Extensions */
        case _SC_NPROCESSORS_CONF:
diff --git a/sys/sys/unistd.h b/sys/sys/unistd.h
index 4b79d5c..96503e3 100644
--- a/sys/sys/unistd.h
+++ b/sys/sys/unistd.h
@@ -109,6 +109,10 @@
 #define        _POSIX_READER_WRITER_LOCKS      200112L
                                /* XPG4.2 shared memory */
 #define        _XOPEN_SHM              0
+                               /* shell */
+#define        _POSIX_SHELL            1
+                               /* regular expressions */
+#define        _POSIX_REGEXP           1
 
 /* access function */
 #define        F_OK            0       /* test for existence of file */
@@ -227,6 +231,23 @@
 #define        _SC_THREAD_PROCESS_SHARED       66
 #define        _SC_THREAD_SAFE_FUNCTIONS       67
 #define        _SC_TTY_NAME_MAX                68
+#define        _SC_HOST_NAME_MAX               69
+#define        _SC_PASS_MAX                    70
+#define        _SC_REGEXP                      71
+#define        _SC_SHELL                       72
+#define        _SC_SYMLOOP_MAX                 73
+
+/* Actually, they are not supported or implemented yet */
+#define        _SC_V6_ILP32_OFF32              74
+#define        _SC_V6_ILP32_OFFBIG             75
+#define        _SC_V6_LP64_OFF64               76
+#define        _SC_V6_LPBIG_OFFBIG             77
+#define        _SC_2_PBS                       80
+#define        _SC_2_PBS_ACCOUNTING            81
+#define        _SC_2_PBS_CHECKPOINT            82
+#define        _SC_2_PBS_LOCATE                83
+#define        _SC_2_PBS_MESSAGE               84
+#define        _SC_2_PBS_TRACK                 85
 
 #ifdef _NETBSD_SOURCE
 /* Commonly provided sysconf() extensions */
diff --git a/usr.bin/getconf/getconf.c b/usr.bin/getconf/getconf.c
index 3a4241f..ddac924 100644
--- a/usr.bin/getconf/getconf.c
+++ b/usr.bin/getconf/getconf.c
@@ -176,6 +176,13 @@ static const struct conf_variable conf_table[] =
   { "GETGR_R_SIZE_MAX",                SYSCONF,        _SC_GETGR_R_SIZE_MAX    
},
   { "GETPW_R_SIZE_MAX",                SYSCONF,        _SC_GETPW_R_SIZE_MAX    
},
 
+  /* Unsorted POSIX Configurable System Variables */
+  { "HOST_NAME_MAX",           SYSCONF,        _SC_HOST_NAME_MAX       },
+  { "PASS_MAX",                        SYSCONF,        _SC_PASS_MAX            
},
+  { "SYMLOOP_MAX",             SYSCONF,        _SC_SYMLOOP_MAX         },
+  { "_POSIX_REGEXP",           SYSCONF,        _SC_REGEXP              },
+  { "_POSIX_SHELL",            SYSCONF,        _SC_SHELL               },
+
 #ifdef _NETBSD_SOURCE
   /* Commonly provided extensions */
   { "NPROCESSORS_CONF",                SYSCONF,        _SC_NPROCESSORS_CONF    
},
-- 
1.5.2.5