diff --git a/audio/audio.c b/audio/audio.c
index f24215b871..3a30103abc 100644
--- a/audio/audio.c
+++ b/audio/audio.c
@@ -215,7 +215,7 @@ static char *audio_alloc_prefix (const char *s)
         pstrcat (r, len + sizeof (qemu_prefix), s);
 
         for (i = 0; i < len; ++i) {
-            u[i] = toupper (u[i]);
+            u[i] = qemu_toupper(u[i]);
         }
     }
     return r;
@@ -470,7 +470,7 @@ static void audio_process_options (const char *prefix,
 
         /* copy while upper-casing, including trailing zero */
         for (i = 0; i <= preflen; ++i) {
-            optname[i + sizeof (qemu_prefix) - 1] = toupper (prefix[i]);
+            optname[i + sizeof (qemu_prefix) - 1] = qemu_toupper(prefix[i]);
         }
         pstrcat (optname, optlen, "_");
         pstrcat (optname, optlen, opt->name);
diff --git a/block-vvfat.c b/block-vvfat.c
index 5fcf7462e8..7d4c934d3f 100644
--- a/block-vvfat.c
+++ b/block-vvfat.c
@@ -1056,7 +1056,7 @@ DLOG(if (stderr == NULL) {
 
     i = strrchr(dirname, ':') - dirname;
     assert(i >= 3);
-    if (dirname[i-2] == ':' && isalpha(dirname[i-1]))
+    if (dirname[i-2] == ':' && qemu_isalpha(dirname[i-1]))
 	/* workaround for DOS drive names */
 	dirname += i-1;
     else
diff --git a/cutils.c b/cutils.c
index 9ef2fa627c..142347d6ac 100644
--- a/cutils.c
+++ b/cutils.c
@@ -72,7 +72,7 @@ int stristart(const char *str, const char *val, const char **ptr)
     p = str;
     q = val;
     while (*q != '\0') {
-        if (toupper(*p) != toupper(*q))
+        if (qemu_toupper(*p) != qemu_toupper(*q))
             return 0;
         p++;
         q++;
diff --git a/monitor.c b/monitor.c
index 8fff3aa752..22360fce30 100644
--- a/monitor.c
+++ b/monitor.c
@@ -1933,7 +1933,7 @@ static void next(void)
 {
     if (pch != '\0') {
         pch++;
-        while (isspace(*pch))
+        while (qemu_isspace(*pch))
             pch++;
     }
 }
@@ -1992,7 +1992,7 @@ static int64_t expr_unary(void)
                     *q++ = *pch;
                 pch++;
             }
-            while (isspace(*pch))
+            while (qemu_isspace(*pch))
                 pch++;
             *q = 0;
             ret = get_monitor_def(&reg, buf);
@@ -2017,7 +2017,7 @@ static int64_t expr_unary(void)
             expr_error("invalid char in expression");
         }
         pch = p;
-        while (isspace(*pch))
+        while (qemu_isspace(*pch))
             pch++;
         break;
     }
@@ -2111,7 +2111,7 @@ static int get_expr(int64_t *pval, const char **pp)
         *pp = pch;
         return -1;
     }
-    while (isspace(*pch))
+    while (qemu_isspace(*pch))
         pch++;
     *pval = expr_sum();
     *pp = pch;
@@ -2126,7 +2126,7 @@ static int get_str(char *buf, int buf_size, const char **pp)
 
     q = buf;
     p = *pp;
-    while (isspace(*p))
+    while (qemu_isspace(*p))
         p++;
     if (*p == '\0') {
     fail:
@@ -2171,7 +2171,7 @@ static int get_str(char *buf, int buf_size, const char **pp)
         }
         p++;
     } else {
-        while (*p != '\0' && !isspace(*p)) {
+        while (*p != '\0' && !qemu_isspace(*p)) {
             if ((q - buf) < buf_size - 1) {
                 *q++ = *p;
             }
@@ -2217,12 +2217,12 @@ static void monitor_handle_command(const char *cmdline)
     /* extract the command name */
     p = cmdline;
     q = cmdname;
-    while (isspace(*p))
+    while (qemu_isspace(*p))
         p++;
     if (*p == '\0')
         return;
     pstart = p;
-    while (*p != '\0' && *p != '/' && !isspace(*p))
+    while (*p != '\0' && *p != '/' && !qemu_isspace(*p))
         p++;
     len = p - pstart;
     if (len > sizeof(cmdname) - 1)
@@ -2258,7 +2258,7 @@ static void monitor_handle_command(const char *cmdline)
                 int ret;
                 char *str;
 
-                while (isspace(*p))
+                while (qemu_isspace(*p))
                     p++;
                 if (*typestr == '?') {
                     typestr++;
@@ -2299,15 +2299,15 @@ static void monitor_handle_command(const char *cmdline)
             {
                 int count, format, size;
 
-                while (isspace(*p))
+                while (qemu_isspace(*p))
                     p++;
                 if (*p == '/') {
                     /* format found */
                     p++;
                     count = 1;
-                    if (isdigit(*p)) {
+                    if (qemu_isdigit(*p)) {
                         count = 0;
-                        while (isdigit(*p)) {
+                        while (qemu_isdigit(*p)) {
                             count = count * 10 + (*p - '0');
                             p++;
                         }
@@ -2346,7 +2346,7 @@ static void monitor_handle_command(const char *cmdline)
                         }
                     }
                 next:
-                    if (*p != '\0' && !isspace(*p)) {
+                    if (*p != '\0' && !qemu_isspace(*p)) {
                         term_printf("invalid char in format: '%c'\n", *p);
                         goto fail;
                     }
@@ -2380,7 +2380,7 @@ static void monitor_handle_command(const char *cmdline)
             {
                 int64_t val;
 
-                while (isspace(*p))
+                while (qemu_isspace(*p))
                     p++;
                 if (*typestr == '?' || *typestr == '.') {
                     if (*typestr == '?') {
@@ -2391,7 +2391,7 @@ static void monitor_handle_command(const char *cmdline)
                     } else {
                         if (*p == '.') {
                             p++;
-                            while (isspace(*p))
+                            while (qemu_isspace(*p))
                                 p++;
                             has_arg = 1;
                         } else {
@@ -2436,7 +2436,7 @@ static void monitor_handle_command(const char *cmdline)
                 c = *typestr++;
                 if (c == '\0')
                     goto bad_type;
-                while (isspace(*p))
+                while (qemu_isspace(*p))
                     p++;
                 has_option = 0;
                 if (*p == '-') {
@@ -2461,7 +2461,7 @@ static void monitor_handle_command(const char *cmdline)
         }
     }
     /* check that all arguments were parsed */
-    while (isspace(*p))
+    while (qemu_isspace(*p))
         p++;
     if (*p != '\0') {
         term_printf("%s: extraneous characters at the end of line\n",
@@ -2609,7 +2609,7 @@ static void parse_cmdline(const char *cmdline,
     p = cmdline;
     nb_args = 0;
     for(;;) {
-        while (isspace(*p))
+        while (qemu_isspace(*p))
             p++;
         if (*p == '\0')
             break;
@@ -2643,7 +2643,7 @@ void readline_find_completion(const char *cmdline)
     /* if the line ends with a space, it means we want to complete the
        next arg */
     len = strlen(cmdline);
-    if (len > 0 && isspace(cmdline[len - 1])) {
+    if (len > 0 && qemu_isspace(cmdline[len - 1])) {
         if (nb_args >= MAX_ARGS)
             return;
         args[nb_args++] = qemu_strdup("");
diff --git a/net.c b/net.c
index f94ff1b177..215df5d1bd 100644
--- a/net.c
+++ b/net.c
@@ -268,7 +268,7 @@ int parse_host_port(struct sockaddr_in *saddr, const char *str)
     if (buf[0] == '\0') {
         saddr->sin_addr.s_addr = 0;
     } else {
-        if (isdigit(buf[0])) {
+        if (qemu_isdigit(buf[0])) {
             if (!inet_aton(buf, &saddr->sin_addr))
                 return -1;
         } else {
diff --git a/qemu-common.h b/qemu-common.h
index 7831409fba..74eaa4dfc5 100644
--- a/qemu-common.h
+++ b/qemu-common.h
@@ -95,6 +95,22 @@ int strstart(const char *str, const char *val, const char **ptr);
 int stristart(const char *str, const char *val, const char **ptr);
 time_t mktimegm(struct tm *tm);
 
+#define qemu_isalnum(c)		isalnum((unsigned char)(c))
+#define qemu_isalpha(c)		isalpha((unsigned char)(c))
+#define qemu_iscntrl(c)		iscntrl((unsigned char)(c))
+#define qemu_isdigit(c)		isdigit((unsigned char)(c))
+#define qemu_isgraph(c)		isgraph((unsigned char)(c))
+#define qemu_islower(c)		islower((unsigned char)(c))
+#define qemu_isprint(c)		isprint((unsigned char)(c))
+#define qemu_ispunct(c)		ispunct((unsigned char)(c))
+#define qemu_isspace(c)		isspace((unsigned char)(c))
+#define qemu_isupper(c)		isupper((unsigned char)(c))
+#define qemu_isxdigit(c)	isxdigit((unsigned char)(c))
+#define qemu_tolower(c)		tolower((unsigned char)(c))
+#define qemu_toupper(c)		toupper((unsigned char)(c))
+#define qemu_isascii(c)		isascii((unsigned char)(c))
+#define qemu_toascii(c)		toascii((unsigned char)(c))
+
 void *qemu_malloc(size_t size);
 void *qemu_realloc(void *ptr, size_t size);
 void *qemu_mallocz(size_t size);
diff --git a/readline.c b/readline.c
index 81bc49120a..e1e963a2cd 100644
--- a/readline.c
+++ b/readline.c
@@ -169,7 +169,7 @@ static void term_backword(void)
 
     /* find first word (backwards) */
     while (start > 0) {
-        if (!isspace(term_cmd_buf[start])) {
+        if (!qemu_isspace(term_cmd_buf[start])) {
             break;
         }
 
@@ -178,7 +178,7 @@ static void term_backword(void)
 
     /* find first space (backwards) */
     while (start > 0) {
-        if (isspace(term_cmd_buf[start])) {
+        if (qemu_isspace(term_cmd_buf[start])) {
             ++start;
             break;
         }
diff --git a/target-ppc/translate_init.c b/target-ppc/translate_init.c
index 02590ae6e9..4208f3de8b 100644
--- a/target-ppc/translate_init.c
+++ b/target-ppc/translate_init.c
@@ -9458,7 +9458,7 @@ const ppc_def_t *cpu_ppc_find_by_name (const char *name)
         p = name;
     check_pvr:
         for (i = 0; i < 8; i++) {
-            if (!isxdigit(*p++))
+            if (!qemu_isxdigit(*p++))
                 break;
         }
         if (i == 8)