os: move string functions to separate source file

Unclutter the huge utils.c a bit, by moving out string functions to
their own source file.

Signed-off-by: Enrico Weigelt, metux IT consult <info@metux.net>
Part-of: <https://gitlab.freedesktop.org/xorg/xserver/-/merge_requests/1336>

os/meson.build

@@ -12,6 +12,7 @@ srcs_os = [
     'oscolor.c',
     'osinit.c',
     'ospoll.c',
+    'string.c',
     'utils.c',
     'xdmauth.c',
     'xsha1.c',

os/string.c

@@ -0,0 +1,73 @@
+/* SPDX-License-Identifier: MIT OR X11
+ *
+ * Copyright © 1987, 1998  The Open Group
+ * Copyright © 2024 Enrico Weigelt, metux IT consult <info@metux.net>
+ */
+#include <dix-config.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "os.h"
+
+char *
+Xstrdup(const char *s)
+{
+    if (s == NULL)
+        return NULL;
+    return strdup(s);
+}
+
+char *
+XNFstrdup(const char *s)
+{
+    char *ret;
+
+    if (s == NULL)
+        return NULL;
+
+    ret = strdup(s);
+    if (!ret)
+        FatalError("XNFstrdup: Out of memory");
+    return ret;
+}
+
+/*
+ * Tokenize a string into a NULL terminated array of strings. Always returns
+ * an allocated array unless an error occurs.
+ */
+char **
+xstrtokenize(const char *str, const char *separators)
+{
+    char **list, **nlist;
+    char *tok, *tmp;
+    unsigned num = 0, n;
+
+    if (!str)
+        return NULL;
+    list = calloc(1, sizeof(*list));
+    if (!list)
+        return NULL;
+    tmp = strdup(str);
+    if (!tmp)
+        goto error;
+    for (tok = strtok(tmp, separators); tok; tok = strtok(NULL, separators)) {
+        nlist = reallocarray(list, num + 2, sizeof(*list));
+        if (!nlist)
+            goto error;
+        list = nlist;
+        list[num] = strdup(tok);
+        if (!list[num])
+            goto error;
+        list[++num] = NULL;
+    }
+    free(tmp);
+    return list;
+
+ error:
+    free(tmp);
+    for (n = 0; n < num; n++)
+        free(list[n]);
+    free(list);
+    return NULL;
+}

os/utils.c

@@ -1131,28 +1131,6 @@ set_font_authorizations(char **authorizations, int *authlen, void *client)
 #endif                          /* TCPCONN */
 }
 
-char *
-Xstrdup(const char *s)
-{
-    if (s == NULL)
-        return NULL;
-    return strdup(s);
-}
-
-char *
-XNFstrdup(const char *s)
-{
-    char *ret;
-
-    if (s == NULL)
-        return NULL;
-
-    ret = strdup(s);
-    if (!ret)
-        FatalError("XNFstrdup: Out of memory");
-    return ret;
-}
-
 void
 SmartScheduleStopTimer(void)
 {
@@ -1916,46 +1894,6 @@ CheckUserAuthorization(void)
 #endif
 }
 
-/*
- * Tokenize a string into a NULL terminated array of strings. Always returns
- * an allocated array unless an error occurs.
- */
-char **
-xstrtokenize(const char *str, const char *separators)
-{
-    char **list, **nlist;
-    char *tok, *tmp;
-    unsigned num = 0, n;
-
-    if (!str)
-        return NULL;
-    list = calloc(1, sizeof(*list));
-    if (!list)
-        return NULL;
-    tmp = strdup(str);
-    if (!tmp)
-        goto error;
-    for (tok = strtok(tmp, separators); tok; tok = strtok(NULL, separators)) {
-        nlist = reallocarray(list, num + 2, sizeof(*list));
-        if (!nlist)
-            goto error;
-        list = nlist;
-        list[num] = strdup(tok);
-        if (!list[num])
-            goto error;
-        list[++num] = NULL;
-    }
-    free(tmp);
-    return list;
-
- error:
-    free(tmp);
-    for (n = 0; n < num; n++)
-        free(list[n]);
-    free(list);
-    return NULL;
-}
-
 /* Format a signed number into a string in a signal safe manner. The string
  * should be at least 21 characters in order to handle all int64_t values.
  */