diff --git a/cmdutils.c b/cmdutils.c
index c6fde336bd..2668ee1486 100644
--- a/cmdutils.c
+++ b/cmdutils.c
@@ -1628,7 +1628,7 @@ int show_help(void *optctx, const char *opt, const char *arg)
 int read_yesno(void)
 {
     int c = getchar();
-    int yesno = (toupper(c) == 'Y');
+    int yesno = (av_toupper(c) == 'Y');
 
     while (c != '\n' && c != EOF)
         c = getchar();
diff --git a/compat/strtod.c b/compat/strtod.c
index d0f9b3d41b..856866564c 100644
--- a/compat/strtod.c
+++ b/compat/strtod.c
@@ -19,7 +19,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <ctype.h>
 #include <limits.h>
 #include <stdlib.h>
 
diff --git a/ffserver.c b/ffserver.c
index f2cf67f694..eee83e5695 100644
--- a/ffserver.c
+++ b/ffserver.c
@@ -1125,7 +1125,7 @@ static int extract_rates(char *rates, int ratelen, const char *request)
         if (av_strncasecmp(p, "Pragma:", 7) == 0) {
             const char *q = p + 7;
 
-            while (*q && *q != '\n' && isspace(*q))
+            while (*q && *q != '\n' && av_isspace(*q))
                 q++;
 
             if (av_strncasecmp(q, "stream-switch-entry=", 20) == 0) {
@@ -1147,7 +1147,7 @@ static int extract_rates(char *rates, int ratelen, const char *request)
                     if (stream_no < ratelen && stream_no >= 0)
                         rates[stream_no] = rate_no;
 
-                    while (*q && *q != '\n' && !isspace(*q))
+                    while (*q && *q != '\n' && !av_isspace(*q))
                         q++;
                 }
 
@@ -1258,7 +1258,7 @@ static void get_word(char *buf, int buf_size, const char **pp)
     p = *pp;
     skip_spaces(&p);
     q = buf;
-    while (!isspace(*p) && *p != '\0') {
+    while (!av_isspace(*p) && *p != '\0') {
         if ((q - buf) < buf_size - 1)
             *q++ = *p;
         p++;
@@ -1275,7 +1275,7 @@ static void get_arg(char *buf, int buf_size, const char **pp)
     int quote;
 
     p = *pp;
-    while (isspace(*p)) p++;
+    while (av_isspace(*p)) p++;
     q = buf;
     quote = 0;
     if (*p == '\"' || *p == '\'')
@@ -1285,7 +1285,7 @@ static void get_arg(char *buf, int buf_size, const char **pp)
             if (*p == quote)
                 break;
         } else {
-            if (isspace(*p))
+            if (av_isspace(*p))
                 break;
         }
         if (*p == '\0')
@@ -1389,7 +1389,7 @@ static IPAddressACL* parse_dynamic_acl(FFStream *stream, HTTPContext *c)
             break;
         line_num++;
         p = line;
-        while (isspace(*p))
+        while (av_isspace(*p))
             p++;
         if (*p == '\0' || *p == '#')
             continue;
@@ -1540,7 +1540,7 @@ static int http_parse_request(HTTPContext *c)
     for (p = c->buffer; *p && *p != '\r' && *p != '\n'; ) {
         if (av_strncasecmp(p, "User-Agent:", 11) == 0) {
             useragent = p + 11;
-            if (*useragent && *useragent != '\n' && isspace(*useragent))
+            if (*useragent && *useragent != '\n' && av_isspace(*useragent))
                 useragent++;
             break;
         }
@@ -1668,7 +1668,7 @@ static int http_parse_request(HTTPContext *c)
             char *eoh;
             char hostbuf[260];
 
-            while (isspace(*hostinfo))
+            while (av_isspace(*hostinfo))
                 hostinfo++;
 
             eoh = strchr(hostinfo, '\n');
@@ -4100,7 +4100,7 @@ static int parse_ffconfig(const char *filename)
             break;
         line_num++;
         p = line;
-        while (isspace(*p))
+        while (av_isspace(*p))
             p++;
         if (*p == '\0' || *p == '#')
             continue;
@@ -4237,7 +4237,7 @@ static int parse_ffconfig(const char *filename)
                 get_arg(arg, sizeof(arg), &p);
                 p1 = arg;
                 fsize = strtod(p1, &p1);
-                switch(toupper(*p1)) {
+                switch(av_toupper(*p1)) {
                 case 'K':
                     fsize *= 1024;
                     break;
diff --git a/libavcodec/dvdsubdec.c b/libavcodec/dvdsubdec.c
index a5c90cd7fa..cb268b8dfe 100644
--- a/libavcodec/dvdsubdec.c
+++ b/libavcodec/dvdsubdec.c
@@ -24,6 +24,7 @@
 #include "libavutil/colorspace.h"
 #include "libavutil/opt.h"
 #include "libavutil/imgutils.h"
+#include "libavutil/avstring.h"
 
 //#define DEBUG
 
@@ -523,7 +524,7 @@ static void parse_palette(DVDSubContext *ctx, char *p)
     ctx->has_palette = 1;
     for(i=0;i<16;i++) {
         ctx->palette[i] = strtoul(p, &p, 16);
-        while(*p == ',' || isspace(*p))
+        while(*p == ',' || av_isspace(*p))
             p++;
     }
 }
diff --git a/libavcodec/realtextdec.c b/libavcodec/realtextdec.c
index 102e0d924f..45788977b5 100644
--- a/libavcodec/realtextdec.c
+++ b/libavcodec/realtextdec.c
@@ -35,11 +35,11 @@ static int rt_event_to_ass(AVBPrint *buf, const char *p)
 
     while (*p) {
         if (*p != '<') {
-            if (!isspace(*p))
+            if (!av_isspace(*p))
                 av_bprint_chars(buf, *p, 1);
             else if (!prev_chr_is_space)
                 av_bprint_chars(buf, ' ', 1);
-            prev_chr_is_space = isspace(*p);
+            prev_chr_is_space = av_isspace(*p);
         } else {
             const char *end = strchr(p, '>');
             if (!end)
diff --git a/libavcodec/samidec.c b/libavcodec/samidec.c
index c04b8a336e..39ac6082bc 100644
--- a/libavcodec/samidec.c
+++ b/libavcodec/samidec.c
@@ -52,7 +52,7 @@ static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src)
         p = av_stristr(p, "<P");
         if (!p)
             break;
-        if (p[2] != '>' && !isspace(p[2])) { // avoid confusion with tags such as <PRE>
+        if (p[2] != '>' && !av_isspace(p[2])) { // avoid confusion with tags such as <PRE>
             p++;
             continue;
         }
@@ -70,7 +70,7 @@ static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src)
         }
 
         /* if empty event -> skip subtitle */
-        while (isspace(*p))
+        while (av_isspace(*p))
             p++;
         if (!strncmp(p, "&nbsp;", 6)) {
             ret = -1;
@@ -80,7 +80,7 @@ static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src)
         /* extract the text, stripping most of the tags */
         while (*p) {
             if (*p == '<') {
-                if (!av_strncasecmp(p, "<P", 2) && (p[2] == '>' || isspace(p[2])))
+                if (!av_strncasecmp(p, "<P", 2) && (p[2] == '>' || av_isspace(p[2])))
                     break;
                 if (!av_strncasecmp(p, "<BR", 3))
                     av_bprintf(dst, "\\N");
@@ -92,11 +92,11 @@ static int sami_paragraph_to_ass(AVCodecContext *avctx, const char *src)
                 if (*p == '>')
                     p++;
             }
-            if (!isspace(*p))
+            if (!av_isspace(*p))
                 av_bprint_chars(dst, *p, 1);
             else if (!prev_chr_is_space)
                 av_bprint_chars(dst, ' ', 1);
-            prev_chr_is_space = isspace(*p);
+            prev_chr_is_space = av_isspace(*p);
             p++;
         }
     }
diff --git a/libavcodec/utils.c b/libavcodec/utils.c
index d680f5ae48..0cf60910cc 100644
--- a/libavcodec/utils.c
+++ b/libavcodec/utils.c
@@ -2777,10 +2777,10 @@ int avpriv_unlock_avformat(void)
 
 unsigned int avpriv_toupper4(unsigned int x)
 {
-    return toupper(x & 0xFF)
-           + (toupper((x >> 8) & 0xFF) << 8)
-           + (toupper((x >> 16) & 0xFF) << 16)
-           + (toupper((x >> 24) & 0xFF) << 24);
+    return av_toupper(x & 0xFF)
+           + (av_toupper((x >> 8) & 0xFF) << 8)
+           + (av_toupper((x >> 16) & 0xFF) << 16)
+           + (av_toupper((x >> 24) & 0xFF) << 24);
 }
 
 #if !HAVE_THREADS
diff --git a/libavcodec/xbmdec.c b/libavcodec/xbmdec.c
index 2a41836492..8632db7b0f 100644
--- a/libavcodec/xbmdec.c
+++ b/libavcodec/xbmdec.c
@@ -23,6 +23,7 @@
 #include "avcodec.h"
 #include "internal.h"
 #include "mathops.h"
+#include "libavutil/avstring.h"
 
 static av_cold int xbm_decode_init(AVCodecContext *avctx)
 {
@@ -94,10 +95,10 @@ static int xbm_decode_frame(AVCodecContext *avctx, void *data,
             uint8_t val;
 
             ptr += strcspn(ptr, "x") + 1;
-            if (ptr < end && isxdigit(*ptr)) {
+            if (ptr < end && av_isxdigit(*ptr)) {
                 val = convert(*ptr);
                 ptr++;
-                if (isxdigit(*ptr))
+                if (av_isxdigit(*ptr))
                     val = (val << 4) + convert(*ptr);
                 *dst++ = ff_reverse[val];
             } else {
diff --git a/libavfilter/avfiltergraph.c b/libavfilter/avfiltergraph.c
index 8b18c6f729..2764b8c85a 100644
--- a/libavfilter/avfiltergraph.c
+++ b/libavfilter/avfiltergraph.c
@@ -20,7 +20,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <ctype.h>
 #include <string.h>
 
 #include "libavutil/avassert.h"
diff --git a/libavfilter/graphparser.c b/libavfilter/graphparser.c
index 0ce823a10d..3e85261c38 100644
--- a/libavfilter/graphparser.c
+++ b/libavfilter/graphparser.c
@@ -20,7 +20,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <ctype.h>
 #include <string.h>
 #include <stdio.h>
 
diff --git a/libavfilter/vsrc_cellauto.c b/libavfilter/vsrc_cellauto.c
index 06d9f9aa13..1431717a5f 100644
--- a/libavfilter/vsrc_cellauto.c
+++ b/libavfilter/vsrc_cellauto.c
@@ -30,6 +30,7 @@
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/random_seed.h"
+#include "libavutil/avstring.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "formats.h"
@@ -133,7 +134,7 @@ static int init_pattern_from_string(AVFilterContext *ctx)
         if (*p == '\n' || !*p)
             break;
         else
-            cellauto->buf[i] = !!isgraph(*(p++));
+            cellauto->buf[i] = !!av_isgraph(*(p++));
     }
 
     return 0;
diff --git a/libavfilter/vsrc_life.c b/libavfilter/vsrc_life.c
index d8b8355126..d548ab46e0 100644
--- a/libavfilter/vsrc_life.c
+++ b/libavfilter/vsrc_life.c
@@ -31,6 +31,7 @@
 #include "libavutil/opt.h"
 #include "libavutil/parseutils.h"
 #include "libavutil/random_seed.h"
+#include "libavutil/avstring.h"
 #include "avfilter.h"
 #include "internal.h"
 #include "formats.h"
@@ -212,7 +213,7 @@ static int init_pattern_from_file(AVFilterContext *ctx)
             if (*p == '\n') {
                 p++; break;
             } else
-                life->buf[0][i*life->w + j] = isgraph(*(p++)) ? ALIVE_CELL : 0;
+                life->buf[0][i*life->w + j] = av_isgraph(*(p++)) ? ALIVE_CELL : 0;
         }
     }
     life->buf_idx = 0;
diff --git a/libavformat/hls.c b/libavformat/hls.c
index 0b7d050a5e..4e7af90f33 100644
--- a/libavformat/hls.c
+++ b/libavformat/hls.c
@@ -110,7 +110,7 @@ typedef struct HLSContext {
 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
 {
     int len = ff_get_line(s, buf, maxlen);
-    while (len > 0 && isspace(buf[len - 1]))
+    while (len > 0 && av_isspace(buf[len - 1]))
         buf[--len] = '\0';
     return len;
 }
diff --git a/libavformat/hlsproto.c b/libavformat/hlsproto.c
index 79cf0e498b..8dedcfd7ca 100644
--- a/libavformat/hlsproto.c
+++ b/libavformat/hlsproto.c
@@ -71,7 +71,7 @@ typedef struct HLSContext {
 static int read_chomp_line(AVIOContext *s, char *buf, int maxlen)
 {
     int len = ff_get_line(s, buf, maxlen);
-    while (len > 0 && isspace(buf[len - 1]))
+    while (len > 0 && av_isspace(buf[len - 1]))
         buf[--len] = '\0';
     return len;
 }
diff --git a/libavformat/http.c b/libavformat/http.c
index 59460005d3..1e3cff7947 100644
--- a/libavformat/http.c
+++ b/libavformat/http.c
@@ -298,9 +298,9 @@ static int process_line(URLContext *h, char *line, int line_count,
 
     p = line;
     if (line_count == 0) {
-        while (!isspace(*p) && *p != '\0')
+        while (!av_isspace(*p) && *p != '\0')
             p++;
-        while (isspace(*p))
+        while (av_isspace(*p))
             p++;
         s->http_code = strtol(p, &end, 10);
 
@@ -325,7 +325,7 @@ static int process_line(URLContext *h, char *line, int line_count,
         *p = '\0';
         tag = line;
         p++;
-        while (isspace(*p))
+        while (av_isspace(*p))
             p++;
         if (!av_strcasecmp(tag, "Location")) {
             av_strlcpy(s->location, p, sizeof(s->location));
diff --git a/libavformat/httpauth.c b/libavformat/httpauth.c
index e97aee1f66..5ca48b9c1d 100644
--- a/libavformat/httpauth.c
+++ b/libavformat/httpauth.c
@@ -27,7 +27,6 @@
 #include "libavutil/md5.h"
 #include "urldecode.h"
 #include "avformat.h"
-#include <ctype.h>
 
 static void handle_basic_params(HTTPAuthState *state, const char *key,
                                 int key_len, char **dest, int *dest_len)
@@ -80,8 +79,8 @@ static void choose_qop(char *qop, int size)
     char *ptr = strstr(qop, "auth");
     char *end = ptr + strlen("auth");
 
-    if (ptr && (!*end || isspace(*end) || *end == ',') &&
-        (ptr == qop || isspace(ptr[-1]) || ptr[-1] == ',')) {
+    if (ptr && (!*end || av_isspace(*end) || *end == ',') &&
+        (ptr == qop || av_isspace(ptr[-1]) || ptr[-1] == ',')) {
         av_strlcpy(qop, "auth", size);
     } else {
         qop[0] = 0;
diff --git a/libavformat/oggparsevorbis.c b/libavformat/oggparsevorbis.c
index 0b52bc7c17..da029a47df 100644
--- a/libavformat/oggparsevorbis.c
+++ b/libavformat/oggparsevorbis.c
@@ -122,7 +122,7 @@ ff_vorbis_comment(AVFormatContext * as, AVDictionary **m, const uint8_t *buf, in
             }
 
             for (j = 0; j < tl; j++)
-                tt[j] = toupper(t[j]);
+                tt[j] = av_toupper(t[j]);
             tt[tl] = 0;
 
             memcpy(ct, v, vl);
diff --git a/libavformat/rtmphttp.c b/libavformat/rtmphttp.c
index d21ac67315..3a51f7c429 100644
--- a/libavformat/rtmphttp.c
+++ b/libavformat/rtmphttp.c
@@ -236,7 +236,7 @@ static int rtmp_http_open(URLContext *h, const char *uri, int flags)
             goto fail;
         }
     }
-    while (off > 0 && isspace(rt->client_id[off - 1]))
+    while (off > 0 && av_isspace(rt->client_id[off - 1]))
         off--;
     rt->client_id[off] = '\0';
 
diff --git a/libavformat/subtitles.c b/libavformat/subtitles.c
index 546261605f..37ba0cb0b6 100644
--- a/libavformat/subtitles.c
+++ b/libavformat/subtitles.c
@@ -170,12 +170,12 @@ const char *ff_smil_get_attr_ptr(const char *s, const char *attr)
 
     while (*s) {
         while (*s) {
-            if (!in_quotes && isspace(*s))
+            if (!in_quotes && av_isspace(*s))
                 break;
             in_quotes ^= *s == '"'; // XXX: support escaping?
             s++;
         }
-        while (isspace(*s))
+        while (av_isspace(*s))
             s++;
         if (!av_strncasecmp(s, attr, len) && s[len] == '=')
             return s + len + 1 + (s[len + 1] == '"');
diff --git a/libavformat/urldecode.c b/libavformat/urldecode.c
index b1009037a8..283d912671 100644
--- a/libavformat/urldecode.c
+++ b/libavformat/urldecode.c
@@ -26,7 +26,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <ctype.h>
 #include <string.h>
 
 #include "libavutil/mem.h"
@@ -54,7 +53,7 @@ char *ff_urldecode(const char *url)
         if (c == '%' && s + 2 < url_len) {
             char c2 = url[s++];
             char c3 = url[s++];
-            if (isxdigit(c2) && isxdigit(c3)) {
+            if (av_isxdigit(c2) && av_isxdigit(c3)) {
                 c2 = av_tolower(c2);
                 c3 = av_tolower(c3);
 
diff --git a/libavformat/utils.c b/libavformat/utils.c
index 7f90a9a5e0..1be391fbbf 100644
--- a/libavformat/utils.c
+++ b/libavformat/utils.c
@@ -3641,11 +3641,11 @@ int av_get_frame_filename(char *buf, int buf_size,
         if (c == '%') {
             do {
                 nd = 0;
-                while (isdigit(*p)) {
+                while (av_isdigit(*p)) {
                     nd = nd * 10 + *p++ - '0';
                 }
                 c = *p++;
-            } while (isdigit(c));
+            } while (av_isdigit(c));
 
             switch(c) {
             case '%':
@@ -3866,7 +3866,7 @@ int ff_hex_to_data(uint8_t *data, const char *p)
         p += strspn(p, SPACE_CHARS);
         if (*p == '\0')
             break;
-        c = toupper((unsigned char) *p++);
+        c = av_toupper((unsigned char) *p++);
         if (c >= '0' && c <= '9')
             c = c - '0';
         else if (c >= 'A' && c <= 'F')
@@ -3989,7 +3989,7 @@ void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
         int key_len, dest_len = 0;
 
         /* Skip whitespace and potential commas. */
-        while (*ptr && (isspace(*ptr) || *ptr == ','))
+        while (*ptr && (av_isspace(*ptr) || *ptr == ','))
             ptr++;
         if (!*ptr)
             break;
@@ -4022,7 +4022,7 @@ void ff_parse_key_value(const char *str, ff_parse_key_val_cb callback_get_buf,
             if (*ptr == '\"')
                 ptr++;
         } else {
-            for (; *ptr && !(isspace(*ptr) || *ptr == ','); ptr++)
+            for (; *ptr && !(av_isspace(*ptr) || *ptr == ','); ptr++)
                 if (dest && dest < dest_end)
                     *dest++ = *ptr;
         }
diff --git a/libavutil/avstring.c b/libavutil/avstring.c
index e2422c0a59..9ad1e12711 100644
--- a/libavutil/avstring.c
+++ b/libavutil/avstring.c
@@ -23,7 +23,6 @@
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
-#include <ctype.h>
 
 #include "config.h"
 #include "common.h"
@@ -43,7 +42,7 @@ int av_strstart(const char *str, const char *pfx, const char **ptr)
 
 int av_stristart(const char *str, const char *pfx, const char **ptr)
 {
-    while (*pfx && toupper((unsigned)*pfx) == toupper((unsigned)*str)) {
+    while (*pfx && av_toupper((unsigned)*pfx) == av_toupper((unsigned)*str)) {
         pfx++;
         str++;
     }
diff --git a/libavutil/avstring.h b/libavutil/avstring.h
index b08d78ee8c..3896b5f2bb 100644
--- a/libavutil/avstring.h
+++ b/libavutil/avstring.h
@@ -185,6 +185,30 @@ char *av_get_token(const char **buf, const char *term);
  */
 char *av_strtok(char *s, const char *delim, char **saveptr);
 
+/**
+ * Locale-independent conversion of ASCII isdigit.
+ */
+static inline int av_isdigit(int c)
+{
+    return c >= '0' && c <= '9';
+}
+
+/**
+ * Locale-independent conversion of ASCII isgraph.
+ */
+static inline int av_isgraph(int c)
+{
+    return c > 32 && c < 127;
+}
+
+/**
+ * Locale-independent conversion of ASCII isspace.
+ */
+static inline int av_isspace(int c)
+{
+    return c == ' ' || c == '\f' || c == '\n' || c == '\r' || c == '\t' || c == '\v';
+}
+
 /**
  * Locale-independent conversion of ASCII characters to uppercase.
  */
@@ -205,6 +229,15 @@ static inline int av_tolower(int c)
     return c;
 }
 
+/**
+ * Locale-independent conversion of ASCII isxdigit.
+ */
+static inline int av_isxdigit(int c)
+{
+    c = av_tolower(c);
+    return av_isdigit(c) || (c >= 'a' && c <= 'z');
+}
+
 /**
  * Locale-independent case-insensitive compare.
  * @note This means only ASCII-range characters are case-insensitive
diff --git a/libavutil/common.h b/libavutil/common.h
index 778c757b69..beaf9f7635 100644
--- a/libavutil/common.h
+++ b/libavutil/common.h
@@ -26,7 +26,6 @@
 #ifndef AVUTIL_COMMON_H
 #define AVUTIL_COMMON_H
 
-#include <ctype.h>
 #include <errno.h>
 #include <inttypes.h>
 #include <limits.h>
diff --git a/libavutil/dict.c b/libavutil/dict.c
index 967c9e2fff..3cd7156a04 100644
--- a/libavutil/dict.c
+++ b/libavutil/dict.c
@@ -18,7 +18,6 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
-#include <ctype.h>
 #include <string.h>
 
 #include "avstring.h"
@@ -50,7 +49,7 @@ av_dict_get(AVDictionary *m, const char *key, const AVDictionaryEntry *prev, int
     for(; i<m->count; i++){
         const char *s= m->elems[i].key;
         if(flags & AV_DICT_MATCH_CASE) for(j=0;         s[j]  ==         key[j]  && key[j]; j++);
-        else                               for(j=0; toupper(s[j]) == toupper(key[j]) && key[j]; j++);
+        else                               for(j=0; av_toupper(s[j]) == av_toupper(key[j]) && key[j]; j++);
         if(key[j])
             continue;
         if(s[j] && !(flags & AV_DICT_IGNORE_SUFFIX))
diff --git a/libavutil/eval.c b/libavutil/eval.c
index 5d202249f0..1449e49468 100644
--- a/libavutil/eval.c
+++ b/libavutil/eval.c
@@ -33,6 +33,7 @@
 #include "log.h"
 #include "mathematics.h"
 #include "time.h"
+#include "avstring.h"
 
 typedef struct Parser {
     const AVClass *class;
@@ -637,7 +638,7 @@ int av_expr_parse(AVExpr **expr, const char *s,
         return AVERROR(ENOMEM);
 
     while (*s)
-        if (!isspace(*s++)) *wp++ = s[-1];
+        if (!av_isspace(*s++)) *wp++ = s[-1];
     *wp++ = 0;
 
     p.class      = &class;
diff --git a/libavutil/parseutils.c b/libavutil/parseutils.c
index c67f971792..494801e2de 100644
--- a/libavutil/parseutils.c
+++ b/libavutil/parseutils.c
@@ -426,7 +426,7 @@ static int date_get_num(const char **pp,
     val = 0;
     for(i = 0; i < len_max; i++) {
         c = *p;
-        if (!isdigit(c))
+        if (!av_isdigit(c))
             break;
         val = (val * 10) + c - '0';
         p++;
@@ -446,8 +446,8 @@ char *av_small_strptime(const char *p, const char *fmt, struct tm *dt)
 
     for(;;) {
         /* consume time string until a non whitespace char is found */
-        while (isspace(*fmt)) {
-            while (isspace(*p))
+        while (av_isspace(*fmt)) {
+            while (av_isspace(*p))
                 p++;
             fmt++;
         }
@@ -611,11 +611,11 @@ int av_parse_time(int64_t *timeval, const char *timestr, int duration)
         int n;
         q++;
         for (n = 100000; n >= 1; n /= 10, q++) {
-            if (!isdigit(*q))
+            if (!av_isdigit(*q))
                 break;
             microseconds += n * (*q - '0');
         }
-        while (isdigit(*q))
+        while (av_isdigit(*q))
             q++;
     }