getconf: Support path variables

2 files changed, 61 insertions, 20 deletions

diff --git a/getconf/getconf.1 b/getconf/getconf.1
index 35f9c13..58341ff 100644
--- a/getconf/getconf.1
+++ b/getconf/getconf.1
@@ -1,21 +1,17 @@
-.Dd April 9, 2016
+.Dd August 21, 2018
 .Dt GETCONF 1 "Base Commands Manual"
 .Os "Adélie Linux"
-
 .Sh NAME
 .Nm getconf
 .Nd get system configuration values
-
 .Sh SYNOPSIS
 .Nm
 .Op Fl v Ar specification
 .Ar system_var
-
 .Nm
 .Op Fl v Ar specification
 .Ar path_var
 .Ar pathname
-
 .Sh DESCRIPTION
 In the first form, the
 .Nm
@@ -24,9 +20,9 @@ utility prints the value of the system variable specified by
 on the currently running system, under the specification given for the
 .Fl v
 argument if specified.
-
+.Pp
 Valid system variables are one of the following:
-
+.Pp
 .Bl -bullet -offset indent -compact
 .It
 The variable name of a valid parameter to the
@@ -58,7 +54,7 @@ header as specified in
 .St -p1003.1-2008 ,
 excluding braces.
 .El
-
+.Pp
 In the second form, the
 .Nm
 utility prints the value of the path variable specified by
@@ -68,43 +64,33 @@ for the path specified by
 on the currently running system, under the specification given for the
 .Fl v
 argument if specified.
-
+.Pp
 Valid path variables are those accepted by the
 .Xr fpathconf 3
 function as specified in
 .St -p1003.1-2008 ,
 exluding braces.
-
 .Sh OPTIONS
 .Bl -tag
 .It -v
 Indicates the specification to use.  Currently, this option is unsupported and
 will be ignored.
 .El
-
 .Sh DIAGNOSTICS
 .Ex -std
-
 .Sh SEE ALSO
-
 .Xr confstr 3 ,
 .Xr fpathconf 3 ,
 .Xr sysconf 3 .
-
 .Sh STANDARDS
 The eventual goal for the
 .Nm
 utility is full conformance to
 .St -p1003.1 2013 Edition.
-
 .Sh AUTHORS
 .An A. Wilcox
 .Aq awilfox@adelielinux.org
-
 .Sh BUGS
 The
 .Fl v
 argument is not currently handled correctly.
-.Pp
-.Ar path_var
-variables are not yet supported.
diff --git a/getconf/getconf.c b/getconf/getconf.c
index 8ede268..01265f1 100644
--- a/getconf/getconf.c
+++ b/getconf/getconf.c
@@ -393,6 +393,27 @@ const var_map_t limit_vars[] = {
 const int limit_count = sizeof(limit_vars) / sizeof(limit_vars[0]);
 
 
+const var_map_t path_vars[] = {
+	{ "FILESIZEBITS", _PC_FILESIZEBITS },
+	{ "LINK_MAX", _PC_LINK_MAX },
+	{ "MAX_CANON", _PC_MAX_CANON },
+	{ "MAX_INPUT", _PC_MAX_INPUT },
+	{ "NAME_MAX", _PC_NAME_MAX },
+	{ "PATH_MAX", _PC_PATH_MAX },
+	{ "PIPE_BUF", _PC_PIPE_BUF },
+	{ "POSIX2_SYMLINKS", _PC_2_SYMLINKS },
+	{ "POSIX_ALLOC_SIZE_MIN", _PC_ALLOC_SIZE_MIN },
+	{ "POSIX_REC_INCR_XFER_SIZE", _PC_REC_INCR_XFER_SIZE },
+	{ "POSIX_REC_MAX_XFER_SIZE", _PC_REC_MAX_XFER_SIZE },
+	{ "POSIX_REC_MIN_XFER_SIZE", _PC_REC_MIN_XFER_SIZE },
+	{ "POSIX_REC_XFER_ALIGN", _PC_REC_XFER_ALIGN },
+	{ "SYMLINK_MAX", _PC_SYMLINK_MAX }
+};
+
+
+const int path_count = sizeof(path_vars) / sizeof (path_vars[0]);
+
+
 int do_system_var(char *environment, char *system_var)
 {
 	int var;
@@ -499,7 +520,41 @@ int do_system_var(char *environment, char *system_var)
 
 int do_path_var(char *environment, char *path_var, char *pathname)
 {
-	return -1;
+	int var;
+
+	for(var = 0; var < path_count; var++)
+	{
+		long int result;
+
+		if(strcasecmp(path_vars[var].variable, path_var) != 0)
+		{
+			continue;
+		}
+
+		if(path_vars[var].value == _UNDEFINED_VARIABLE_)
+		{
+			printf("undefined\n");
+			return 0;
+		}
+
+		errno = 0;
+
+		result = pathconf(pathname, path_vars[var].value);
+		if(errno != 0)
+		{
+		/* We know that this is a valid symbol, so don't break
+		 * expectations.
+		 */
+			printf("undefined\n");
+			return 0;
+		}
+
+		printf("%ld\n", result);
+		return 0;
+	}
+
+	fprintf(stderr, "%s: not a recognised system variable\n", path_var);
+	return EINVAL;
 }