1 files changed, 119 insertions, 2 deletions

diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c
index ca693fcd023f..e28cd0c2ca08 100644
--- a/scripts/kconfig/confdata.c
+++ b/scripts/kconfig/confdata.c
@@ -5,6 +5,7 @@
 
 #include <sys/stat.h>
 #include <ctype.h>
+#include <fcntl.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -520,6 +521,119 @@ int conf_write(const char *name)
         return 0;
 }
 
+int conf_split_config(void)
+{
+        char *name, path[128];
+        char *s, *d, c;
+        struct symbol *sym;
+        struct stat sb;
+        int res, i, fd;
+
+        name = getenv("KCONFIG_AUTOCONFIG");
+        if (!name)
+                name = "include/config/auto.conf";
+        conf_read_simple(name, S_DEF_AUTO);
+
+        if (chdir("include/config"))
+                return 1;
+
+        res = 0;
+        for_all_symbols(i, sym) {
+                sym_calc_value(sym);
+                if ((sym->flags & SYMBOL_AUTO) || !sym->name)
+                        continue;
+                if (sym->flags & SYMBOL_WRITE) {
+                        if (sym->flags & SYMBOL_DEF_AUTO) {
+                                /*
+                                 * symbol has old and new value,
+                                 * so compare them...
+                                 */
+                                switch (sym->type) {
+                                case S_BOOLEAN:
+                                case S_TRISTATE:
+                                        if (sym_get_tristate_value(sym) ==
+                                            sym->def[S_DEF_AUTO].tri)
+                                                continue;
+                                        break;
+                                case S_STRING:
+                                case S_HEX:
+                                case S_INT:
+                                        if (!strcmp(sym_get_string_value(sym),
+                                                    sym->def[S_DEF_AUTO].val))
+                                                continue;
+                                        break;
+                                default:
+                                        break;
+                                }
+                        } else {
+                                /*
+                                 * If there is no old value, only 'no' (unset)
+                                 * is allowed as new value.
+                                 */
+                                switch (sym->type) {
+                                case S_BOOLEAN:
+                                case S_TRISTATE:
+                                        if (sym_get_tristate_value(sym) == no)
+                                                continue;
+                                        break;
+                                default:
+                                        break;
+                                }
+                        }
+                } else if (!(sym->flags & SYMBOL_DEF_AUTO))
+                        /* There is neither an old nor a new value. */
+                        continue;
+                /* else
+                 *      There is an old value, but no new value ('no' (unset)
+                 *      isn't saved in auto.conf, so the old value is always
+                 *      different from 'no').
+                 */
+
+                /* Replace all '_' and append ".h" */
+                s = sym->name;
+                d = path;
+                while ((c = *s++)) {
+                        c = tolower(c);
+                        *d++ = (c == '_') ? '/' : c;
+                }
+                strcpy(d, ".h");
+
+                /* Assume directory path already exists. */
+                fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+                if (fd == -1) {
+                        if (errno != ENOENT) {
+                                res = 1;
+                                break;
+                        }
+                        /*
+                         * Create directory components,
+                         * unless they exist already.
+                         */
+                        d = path;
+                        while ((d = strchr(d, '/'))) {
+                                *d = 0;
+                                if (stat(path, &sb) && mkdir(path, 0755)) {
+                                        res = 1;
+                                        goto out;
+                                }
+                                *d++ = '/';
+                        }
+                        /* Try it again. */
+                        fd = open(path, O_WRONLY | O_CREAT | O_TRUNC, 0644);
+                        if (fd == -1) {
+                                res = 1;
+                                break;
+                        }
+                }
+                close(fd);
+        }
+out:
+        if (chdir("../.."))
+                return 1;
+
+        return res;
+}
+
 int conf_write_autoconf(void)
 {
         struct symbol *sym;
@@ -529,8 +643,13 @@ int conf_write_autoconf(void)
         time_t now;
         int i, l;
 
+        sym_clear_all_valid();
+
         file_write_dep("include/config/auto.conf.cmd");
 
+        if (conf_split_config())
+                return 1;
+
         out = fopen(".tmpconfig", "w");
         if (!out)
                 return 1;
@@ -558,8 +677,6 @@ int conf_write_autoconf(void)
                        "#define AUTOCONF_INCLUDED\n",
                        sym_get_string_value(sym), ctime(&now));
 
-        sym_clear_all_valid();
-
         for_all_symbols(i, sym) {
                 sym_calc_value(sym);
                 if (!(sym->flags & SYMBOL_WRITE) || !sym->name)