From 88a6dd1e810fd46be10ff57154027f6cc9fd3038 Mon Sep 17 00:00:00 2001
From: Andrea Mazzoleni <amadvance@gmail.com>
Date: Thu, 21 May 2026 00:03:49 +0200
Subject: [PATCH] Cast to unsigned char when using ctype macros

---
 cmdline/support.c | 10 +++++-----
 cmdline/unix.c    | 14 +++++++-------
 2 files changed, 12 insertions(+), 12 deletions(-)

diff --git a/cmdline/support.c b/cmdline/support.c
index d6bc0dc8..39c6f953 100644
--- a/cmdline/support.c
+++ b/cmdline/support.c
@@ -871,7 +871,7 @@ char* strpolish(char* s)
 	char* i = s;
 
 	while (*i) {
-		if (isspace(*i) || !isprint(*i))
+		if (isspace((unsigned char)*i) || !isprint((unsigned char)*i))
 			*i = ' ';
 		++i;
 	}
@@ -1180,7 +1180,7 @@ int mkancestor(const char* file)
 
 #ifdef _WIN32
 	/* if it's a drive specification like "C:" */
-	if (isalpha(dir[0]) && dir[1] == ':' && dir[2] == 0) {
+	if (isalpha((unsigned char)dir[0]) && dir[1] == ':' && dir[2] == 0) {
 		/* nothing more to do */
 		return 0;
 	}
@@ -1799,9 +1799,9 @@ char* strdup_nofail(const char* str)
 static int smatch(const char* str, const char* pattern)
 {
 	while (*pattern) {
-		if (isspace(*pattern)) {
+		if (isspace((unsigned char)*pattern)) {
 			++pattern;
-			while (isspace(*str))
+			while (isspace((unsigned char)*str))
 				++str;
 		} else if (*pattern == *str) {
 			++pattern;
@@ -1961,7 +1961,7 @@ int smartctl_attribute(FILE* f, const char* file, const char* name, struct smart
 		log_tag("smartctl:%s:%s:out: %s\n", file, name, s);
 
 		/* skip initial spaces */
-		while (isspace(*s))
+		while (isspace((unsigned char)*s))
 			++s;
 
 		if (*s == 0) {
diff --git a/cmdline/unix.c b/cmdline/unix.c
index 5874307c..4c7cea85 100644
--- a/cmdline/unix.c
+++ b/cmdline/unix.c
@@ -609,7 +609,7 @@ static int tagread(const char* path, const char* tag, char* value, size_t value_
 
 		/* start with a space */
 		if (p != buf) {
-			if (!isspace(*p))
+			if (!isspace((unsigned char)*p))
 				continue;
 			++p;
 		}
@@ -636,7 +636,7 @@ static int tagread(const char* path, const char* tag, char* value, size_t value_
 
 	/* terminate at the first space */
 	e = i;
-	while (*e != 0 && !isspace(*e))
+	while (*e != 0 && !isspace((unsigned char)*e))
 		++e;
 	*e = 0;
 
@@ -1533,7 +1533,7 @@ static dev_t devread(const char* path)
 	}
 
 	mi = strtoul(e + 1, &e, 10);
-	if (*e != 0 && !isspace(*e)) {
+	if (*e != 0 && !isspace((unsigned char)*e)) {
 		/* LCOV_EXCL_START */
 		log_fatal(EEXTERNAL, "Invalid format in '%s' for '%s'.\n", path, buf);
 		return 0;
@@ -1675,17 +1675,17 @@ static int devstat(dev_t device, uint64_t* count)
 		unsigned long long v;
 
 		/* skip spaces */
-		while (*i && isspace(*i))
+		while (*i && isspace((unsigned char)*i))
 			++i;
 
 		/* read digits */
 		n = i;
-		while (*i && isdigit(*i))
+		while (*i && isdigit((unsigned char)*i))
 			++i;
 
 		if (i == n) /* if no digit, abort */
 			break;
-		if (*i == 0 || !isspace(*i)) /* if no space, abort */
+		if (*i == 0 || !isspace((unsigned char)*i)) /* if no space, abort */
 			break;
 		*i++ = 0; /* put a terminator */
 
@@ -2617,7 +2617,7 @@ int ambient_temperature(void)
 				continue;
 
 			temp = strtol(value, &e, 10) / 1000;
-			if (*e != 0 && !isspace(*e))
+			if (*e != 0 && !isspace((unsigned char)*e))
 				continue;
 
 			/* cut the file name at "_input" */