kbuild: support at least non-interactive mode on Windows

without POSIX, kbuild has some trouble compiling its support
executables. Luckily, the parts that really lean on POSIX functionality
are pretty much all only needed when configuring the build
interactively.

When compiling BusyBox for Win32, we do not actually need interactive
configuration at all: we simply choose the default. Therefore, a lot of
the stuff that is typically built for the Kconfig system is totally
unnecessary (such as: compiling documentation via fork()&exec(), changing
the window size, etc).

Liberally put all of the problematic code behind #ifndef __MINGW32__
guards, just to get `make mingw64_defconfig` going in Git for Windows'
SDK (which is a special-purpose version of MSYS2).

Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de>

5 files changed, 76 insertions, 3 deletions

diff --git a/scripts/basic/docproc.c b/scripts/basic/docproc.c
index 720098a23..bfc1a9844 100644
--- a/scripts/basic/docproc.c
+++ b/scripts/basic/docproc.c
@@ -38,7 +38,9 @@
 #include <unistd.h>
 #include <limits.h>
 #include <sys/types.h>
+#ifndef __MINGW32__
 #include <sys/wait.h>
+#endif
 //bbox disabled: #include <alloca.h>
 
 /* exitstatus is used to keep track of any failing calls to kernel-doc,
@@ -78,12 +80,24 @@ void usage (void)
  */
 void exec_kernel_doc(char **svec)
 {
+#ifndef __MINGW32__
         pid_t pid;
         int ret;
+#endif
         char *real_filename;
         int rflen;
 
         /* Make sure output generated so far are flushed */
+#ifdef __MINGW32__
+        fflush(stdout);
+        rflen  = strlen(getenv("SRCTREE"));
+        rflen += strlen(KERNELDOCPATH KERNELDOC);
+        real_filename = alloca(rflen + 1);
+        strcpy(real_filename, getenv("SRCTREE"));
+        strcat(real_filename, KERNELDOCPATH KERNELDOC);
+        fprintf(stderr, "NOTIMPL: exec %s\n", real_filename);
+        exit(1);
+#else
         fflush(stdout);
         switch(pid=fork()) {
                 case -1:
@@ -106,6 +120,7 @@ void exec_kernel_doc(char **svec)
                 exitstatus |= WEXITSTATUS(ret);
         else
                 exitstatus = 0xff;
+#endif
 }
 
 /* Types used to create list of all exported symbols in a number of files */
diff --git a/scripts/basic/split-include.c b/scripts/basic/split-include.c
index e328788e2..8127fe261 100644
--- a/scripts/basic/split-include.c
+++ b/scripts/basic/split-include.c
@@ -39,8 +39,6 @@
         exit(1);                                                        \
     }
 
-
-
 int main(int argc, const char * argv [])
 {
     const char * str_my_name;
@@ -89,7 +87,11 @@ int main(int argc, const char * argv [])
     /* Make output directory if needed. */
     if (stat(str_dir_config, &stat_buf) != 0)
     {
+#ifdef __MINGW32__
+        if (mkdir(str_dir_config) != 0)
+#else
         if (mkdir(str_dir_config, 0755) != 0)
+#endif
             ERROR_EXIT(str_dir_config);
     }
 
@@ -148,7 +150,12 @@ int main(int argc, const char * argv [])
                 {
                     ptarget[islash] = '\0';
                     if (stat(ptarget, &stat_buf) != 0
-                    &&  mkdir(ptarget, 0755)     != 0)
+#ifdef __MINGW32__
+                    &&  mkdir(ptarget)           != 0
+#else
+                    &&  mkdir(ptarget, 0755)     != 0
+#endif
+                    )
                         ERROR_EXIT( ptarget );
                     ptarget[islash] = '/';
                 }
diff --git a/scripts/kconfig/conf.c b/scripts/kconfig/conf.c
index ea2446a89..41ac23936 100644
--- a/scripts/kconfig/conf.c
+++ b/scripts/kconfig/conf.c
@@ -153,9 +153,14 @@ static void conf_askvalue(struct symbol *sym, const char *def)
                         break;
                 }
         case set_random:
+#ifdef __MINGW32__
+                fprintf(stderr, "set_random not supported\n");
+                exit(1);
+#else
                 do {
                         val = (tristate)(random() % 3);
                 } while (!sym_tristate_within_range(sym, val));
+#endif
                 switch (val) {
                 case no: line[0] = 'n'; break;
                 case mod: line[0] = 'm'; break;
@@ -366,7 +371,12 @@ static int conf_choice(struct menu *menu)
                                 continue;
                         break;
                 case set_random:
+#ifdef __MINGW32__
+                fprintf(stderr, "set_random not supported\n");
+                exit(1);
+#else
                         def = (random() % cnt) + 1;
+#endif
                 case set_default:
                 case set_yes:
                 case set_mod:
@@ -522,8 +532,13 @@ int main(int ac, char **av)
                         input_mode = set_yes;
                         break;
                 case 'r':
+#ifdef __MINGW32__
+                        fprintf(stderr, "set_random not supported\n");
+                        exit(1);
+#else
                         input_mode = set_random;
                         srandom(time(NULL));
+#endif
                         break;
                 case 'h':
                 case '?':
diff --git a/scripts/kconfig/mconf.c b/scripts/kconfig/mconf.c
index e2e6ca8c7..d3ad12d90 100644
--- a/scripts/kconfig/mconf.c
+++ b/scripts/kconfig/mconf.c
@@ -12,8 +12,10 @@
 /* On Darwin, this may be needed to get SIGWINCH: */
 #define _DARWIN_C_SOURCE 1
 
+#ifndef __MINGW32__
 #include <sys/ioctl.h>
 #include <sys/wait.h>
+#endif
 #include <ctype.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -23,7 +25,9 @@
 #include <stdlib.h>
 #include <string.h>
 #include <strings.h> /* for strcasecmp */
+#ifndef __MINGW32__
 #include <termios.h>
+#endif
 #include <unistd.h>
 #include <locale.h>
 
@@ -266,11 +270,15 @@ static char input_buf[4096];
 static const char filename[] = ".config";
 static char *args[1024], **argptr = args;
 static int indent;
+#ifndef __MINGW32__
 static struct termios ios_org;
+#endif
 static int rows = 0, cols = 0;
 static struct menu *current_menu;
 static int child_count;
+#ifndef __MINGW32__
 static int do_resize;
+#endif
 static int single_menu_mode;
 
 static void conf(struct menu *menu);
@@ -290,6 +298,9 @@ static int cprint(const char *fmt, ...);
 
 static void init_wsize(void)
 {
+#ifdef __MINGW32__
+        fprintf(stderr, "Skipping attempt to change window size\n");
+#else
         struct winsize ws;
         char *env;
 
@@ -321,6 +332,7 @@ static void init_wsize(void)
 
         rows -= 4;
         cols -= 5;
+#endif
 }
 
 static void cprint_init(void)
@@ -457,6 +469,10 @@ static void winch_handler(int sig)
 
 static int exec_conf(void)
 {
+#ifdef __MINGW32__
+        fprintf(stderr, "exec_conf not implemented\n");
+        exit(1);
+#else
         int pipefd[2], stat, size;
         sigset_t sset, osset;
 
@@ -530,6 +546,7 @@ static int exec_conf(void)
         sigprocmask(SIG_SETMASK, &osset, NULL);
 
         return WEXITSTATUS(stat);
+#endif
 }
 
 static void search_conf(void)
@@ -1044,7 +1061,9 @@ static void conf_save(void)
 
 static void conf_cleanup(void)
 {
+#ifndef __MINGW32__
         tcsetattr(1, TCSAFLUSH, &ios_org);
+#endif
         unlink(".help.tmp");
         unlink("lxdialog.scrltmp");
 }
@@ -1073,7 +1092,9 @@ int main(int ac, char **av)
                         single_menu_mode = 1;
         }
 
+#ifndef __MINGW32__
         tcgetattr(1, &ios_org);
+#endif
         atexit(conf_cleanup);
         init_wsize();
         conf(&rootmenu);
diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c
index 3d7877afc..63199cd93 100644
--- a/scripts/kconfig/symbol.c
+++ b/scripts/kconfig/symbol.c
@@ -6,8 +6,10 @@
 #include <ctype.h>
 #include <stdlib.h>
 #include <string.h>
+#ifndef __MINGW32__
 #include <regex.h>
 #include <sys/utsname.h>
+#endif
 
 #define LKC_DIRECT_LINK
 #include "lkc.h"
@@ -44,7 +46,9 @@ void sym_add_default(struct symbol *sym, const char *def)
 void sym_init(void)
 {
         struct symbol *sym;
+#ifndef __MINGW32__
         struct utsname uts;
+#endif
         char *p;
         static bool inited = false;
 
@@ -52,7 +56,9 @@ void sym_init(void)
                 return;
         inited = true;
 
+#ifndef __MINGW32__
         uname(&uts);
+#endif
 
         sym = sym_lookup("ARCH", 0);
         sym->type = S_STRING;
@@ -71,7 +77,11 @@ void sym_init(void)
         sym = sym_lookup("UNAME_RELEASE", 0);
         sym->type = S_STRING;
         sym->flags |= SYMBOL_AUTO;
+#ifdef __MINGW32__
+        sym_add_default(sym, "UNKNOWN");
+#else
         sym_add_default(sym, uts.release);
+#endif
 }
 
 enum symbol_type sym_get_type(struct symbol *sym)
@@ -720,6 +730,10 @@ struct symbol *sym_find(const char *name)
 
 struct symbol **sym_re_search(const char *pattern)
 {
+#ifdef __MINGW32__
+        fprintf(stderr, "NOTIMPL: sym_re_search\n");
+        exit(1);
+#else
         struct symbol *sym, **sym_arr = NULL;
         int i, cnt, size;
         regex_t re;
@@ -752,6 +766,7 @@ struct symbol **sym_re_search(const char *pattern)
         regfree(&re);
 
         return sym_arr;
+#endif
 }