[PATCH 5/5] exportfs: Use xlog() for error reporting

[Chuck Lever <chuck.lever@oracle.com>]

exportfs already invokes xlog_open() because libexport.a uses xlog()
exclusively for error reporting and debugging messages.  If we can
use xlog() throughout exportfs itself, that enables xlog debugging
messages everywhere in the code path.

In addition, use xlog() instead of fprintf(stderr) for reporting
errors in exportfs.c, to be consistent with libexport.a and other
components of nfs-utils.

Signed-off-by: Chuck Lever <chuck.lever@oracle.com>
---

 utils/exportfs/exportfs.c |   56 +++++++++++++++++++++++----------------------
 1 files changed, 29 insertions(+), 27 deletions(-)

diff --git a/utils/exportfs/exportfs.c b/utils/exportfs/exportfs.c
index 93bad32..8496d82 100644
--- a/utils/exportfs/exportfs.c
+++ b/utils/exportfs/exportfs.c
@@ -37,7 +37,7 @@ static void	unexportfs(char *arg, int verbose);
 static void	exports_update(int verbose);
 static void	dump(int verbose);
 static void	error(nfs_export *exp, int err);
-static void	usage(void);
+static void	usage(const char *progname);
 static void	validate_export(nfs_export *exp);
 static int	matchhostname(const char *hostname1, const char *hostname2);
 
@@ -45,6 +45,7 @@ int
 main(int argc, char **argv)
 {
 	char	*options = NULL;
+	char	*progname = NULL;
 	int	f_export = 1;
 	int	f_all = 0;
 	int	f_verbose = 0;
@@ -54,7 +55,14 @@ main(int argc, char **argv)
 	int	new_cache = 0;
 	int	force_flush = 0;
 
-	xlog_open("exportfs");
+	if ((progname = strrchr(argv[0], '/')) != NULL)
+		progname++;
+	else
+		progname = argv[0];
+
+	xlog_open(progname);
+	xlog_stderr(1);
+	xlog_syslog(0);
 
 	export_errno = 0;
 
@@ -83,21 +91,21 @@ main(int argc, char **argv)
 			force_flush = 1;
 			break;
 		default:
-			usage();
+			usage(progname);
 			break;
 		}
 	}
 
 	if (optind != argc && f_all) {
-		fprintf(stderr,"exportfs: extra arguments are not permitted with -a or -r.\n");
+		xlog(L_ERROR, "extra arguments are not permitted with -a or -r");
 		return 1;
 	}
 	if (f_ignore && (f_all || ! f_export)) {
-		fprintf(stderr,"exportfs: -i not meaningful with -a, -r or -u.\n");
+		xlog(L_ERROR, "-i not meaningful with -a, -r or -u");
 		return 1;
 	}
 	if (f_reexport && ! f_export) {
-		fprintf(stderr, "exportfs: -r and -u are incompatible.\n");
+		xlog(L_ERROR, "-r and -u are incompatible");
 		return 1;
 	}
 	new_cache = check_new_cache();
@@ -106,8 +114,10 @@ main(int argc, char **argv)
 			if (new_cache)
 				cache_flush(1);
 			else {
-				fprintf(stderr, "exportfs: -f: only available with new cache controls: mount /proc/fs/nfsd first\n");
-				exit(1);
+				xlog(L_ERROR, "-f is available only "
+					"with new cache controls. "
+					"Mount /proc/fs/nfsd first");
+				return 1;
 			}
 			return 0;
 		} else {
@@ -245,7 +255,7 @@ exportfs(char *arg, char *options, int verbose)
 		*path++ = '\0';
 
 	if (!path || *path != '/') {
-		fprintf(stderr, "Invalid exporting option: %s\n", arg);
+		xlog(L_ERROR, "Invalid exporting option: %s", arg);
 		return;
 	}
 
@@ -291,8 +301,7 @@ unexportfs(char *arg, int verbose)
 		*path++ = '\0';
 
 	if (!path || *path != '/') {
-		fprintf(stderr, "Invalid unexporting option: %s\n",
-			arg);
+		xlog(L_ERROR, "Invalid unexporting option: %s", arg);
 		return;
 	}
 
@@ -387,14 +396,12 @@ validate_export(nfs_export *exp)
 	int fs_has_fsid = 0;
 
 	if (stat(path, &stb) < 0) {
-		fprintf(stderr, "exportfs: Warning: %s does not exist\n",
-			path);
+		xlog(L_ERROR, "Failed to stat %s: %m \n", path);
 		return;
 	}
 	if (!S_ISDIR(stb.st_mode) && !S_ISREG(stb.st_mode)) {
-		fprintf(stderr, "exportfs: Warning: %s is neither "
-			"a directory nor a file.\n"
-			"     remote access will fail\n", path);
+		xlog(L_ERROR, "%s is neither a directory nor a file. "
+			"Remote access will fail", path);
 		return;
 	}
 	if (!can_test())
@@ -407,19 +414,14 @@ validate_export(nfs_export *exp)
 	if ((exp->m_export.e_flags & NFSEXP_FSID) || exp->m_export.e_uuid ||
 	    fs_has_fsid) {
 		if ( !test_export(path, 1)) {
-			fprintf(stderr, "exportfs: Warning: %s does not "
-				"support NFS export.\n",
-				path);
+			xlog(L_ERROR, "%s does not support NFS export", path);
 			return;
 		}
 	} else if ( ! test_export(path, 0)) {
 		if (test_export(path, 1))
-			fprintf(stderr, "exportfs: Warning: %s requires fsid= "
-				"for NFS export\n", path);
+			xlog(L_ERROR, "%s requires fsid= for NFS export", path);
 		else
-			fprintf(stderr, "exportfs: Warning: %s does not "
-				"support NFS export.\n",
-				path);
+			xlog(L_ERROR, "%s does not support NFS export", path);
 		return;
 
 	}
@@ -602,13 +604,13 @@ dump(int verbose)
 static void
 error(nfs_export *exp, int err)
 {
-	fprintf(stderr, "%s:%s: %s\n", exp->m_client->m_hostname, 
+	xlog(L_ERROR, "%s:%s: %s\n", exp->m_client->m_hostname,
 		exp->m_export.e_path, strerror(err));
 }
 
 static void
-usage(void)
+usage(const char *progname)
 {
-	fprintf(stderr, "usage: exportfs [-aruv] [host:/path]\n");
+	fprintf(stderr, "usage: %s [-aruv] [host:/path]\n", progname);
 	exit(1);
 }