libmount: fix compiler warnings [-Wunused-parameter -Wsign-compare]

Signed-off-by: Karel Zak <kzak@redhat.com>

libmount/samples/mount.c

@@ -79,7 +79,7 @@ static void __attribute__((__noreturn__)) print_version(void)
 	exit(EX_SUCCESS);
 }
 
-static int table_parser_errcb(struct libmnt_table *tb,
+static int table_parser_errcb(struct libmnt_table *tb __attribute__((__unused__)),
 			const char *filename, int line)
 {
 	if (filename)

libmount/src/cache.c

@@ -86,7 +86,7 @@ struct libmnt_cache *mnt_new_cache(void)
  */
 void mnt_free_cache(struct libmnt_cache *cache)
 {
-	int i;
+	size_t i;
 
 	if (!cache)
 		return;
@@ -181,7 +181,7 @@ static int cache_add_tag(struct libmnt_cache *cache, const char *tagname,
  */
 static const char *cache_find_path(struct libmnt_cache *cache, const char *path)
 {
-	int i;
+	size_t i;
 
 	assert(cache);
 	assert(path);
@@ -205,7 +205,7 @@ static const char *cache_find_path(struct libmnt_cache *cache, const char *path)
 static const char *cache_find_tag(struct libmnt_cache *cache,
 			const char *token, const char *value)
 {
-	int i;
+	size_t i;
 	size_t tksz;
 
 	assert(cache);
@@ -231,7 +231,7 @@ static const char *cache_find_tag(struct libmnt_cache *cache,
 static char *cache_find_tag_value(struct libmnt_cache *cache,
 			const char *devname, const char *token)
 {
-	int i;
+	size_t i;
 
 	assert(cache);
 	assert(devname);
@@ -297,7 +297,8 @@ static int cache_get_probe(struct libmnt_cache *cache, const char *devname,
  */
 int mnt_cache_read_tags(struct libmnt_cache *cache, const char *devname)
 {
-	int i, ntags = 0, rc;
+	size_t i, ntags = 0;
+	int rc;
 	const char *tags[] = { "LABEL", "UUID", "TYPE" };
 
 	assert(cache);
@@ -355,7 +356,7 @@ int mnt_cache_read_tags(struct libmnt_cache *cache, const char *devname)
 		ntags++;
 	}
 
-	DBG(CACHE, mnt_debug_h(cache, "\tread %d tags", ntags));
+	DBG(CACHE, mnt_debug_h(cache, "\tread %zd tags", ntags));
 	return ntags ? 0 : 1;
 error:
 	return -1;

libmount/src/context.c

@@ -1244,7 +1244,7 @@ int mnt_context_prepare_helper(struct libmnt_context *cxt, const char *name,
 						path, name, type);
 		path = strtok_r(NULL, ":", &p);
 
-		if (rc >= sizeof(helper) || rc < 0)
+		if (rc < 0 || (size_t) rc >= sizeof(helper))
 			continue;
 
 		rc = stat(helper, &st);
@@ -1595,7 +1595,9 @@ int mnt_context_set_syscall_status(struct libmnt_context *cxt, int status)
  *
  * Returns: 0 or negative number in case of error.
  */
-int mnt_context_strerror(struct libmnt_context *cxt, char *buf, size_t bufsiz)
+int mnt_context_strerror(struct libmnt_context *cxt __attribute__((__unused__)),
+			 char *buf __attribute__((__unused__)),
+			 size_t bufsiz __attribute__((__unused__)))
 {
 	/* TODO: based on cxt->syscall_errno or cxt->helper_status */
 	return 0;
@@ -1605,7 +1607,7 @@ int mnt_context_strerror(struct libmnt_context *cxt, char *buf, size_t bufsiz)
  * mnt_context_init_helper
  * @cxt: mount context
  * @action: MNT_ACT_{UMOUNT,MOUNT}
- * @flags: not used
+ * @flags: not used now
  *
  * This function infors libmount that used from [u]mount.type helper.
  *
@@ -1618,7 +1620,8 @@ int mnt_context_strerror(struct libmnt_context *cxt, char *buf, size_t bufsiz)
  *
  * Returns: 0 on success, negative number in case of error.
  */
-int mnt_context_init_helper(struct libmnt_context *cxt, int action, int flags)
+int mnt_context_init_helper(struct libmnt_context *cxt, int action,
+			    int flags __attribute__((__unused__)))
 {
 	int rc = mnt_context_disable_helpers(cxt, TRUE);
 

libmount/src/lock.c

@@ -236,7 +236,7 @@ err:
  * traditional mtab locking
  */
 
-static void mnt_lockalrm_handler(int sig)
+static void mnt_lockalrm_handler(int sig __attribute__((__unused__)))
 {
 	/* do nothing, say nothing, be nothing */
 }

libmount/src/utils.c

@@ -263,7 +263,8 @@ static int check_option(const char *haystack, size_t len,
 
 	for (p = haystack; p && p < haystack + len; p++) {
 		char *sep = strchr(p, ',');
-		size_t plen = sep ? sep - p : len - (p - haystack);
+		size_t plen = sep ? (size_t) (sep - p) :
+				    len - (p - haystack);
 
 		if (plen == needle_len) {
 			if (!strncmp(p, needle, plen))
@@ -309,7 +310,8 @@ int mnt_match_options(const char *optstr, const char *pattern)
 
 	for (p = pattern; p < pattern + len; p++) {
 		char *sep = strchr(p, ',');
-		size_t plen = sep ? sep - p : len - (p - pattern);
+		size_t plen = sep ? (size_t) (sep - p) :
+				    len - (p - pattern);
 
 		if (!plen)
 			continue; /* if two ',' appear in a row */