win32: allow hardcoded list of applets to override

The environment variable BB_OVERRIDE_APPLETS provides control over
which applets are preferred in standalone shell mode.  Allow a
similar list to be hardcoded in the binary with the OVERRIDE_APPLETS
configuration string.

The environment variable is checked first.  If it doesn't override
the applet the hardcoded string is then checked too.

The default for OVERRIDE_APPLETS is an empty string.  In this case
the size and behaviour of the binary is unchanged.

5 files changed, 26 insertions, 6 deletions

diff --git a/Config.in b/Config.in
index 0da09c1cd..0a6d57327 100644
--- a/Config.in
+++ b/Config.in
@@ -556,6 +556,16 @@ config FEATURE_EXTRA_FILE_DATA
         determine the ownership of files so that, for example, 'ls' can
         distinguish files belonging to the current user.
 
+config OVERRIDE_APPLETS
+        string "Override applets"
+        default ""
+        depends on PLATFORM_MINGW32 && (FEATURE_PREFER_APPLETS || FEATURE_SH_STANDALONE)
+        help
+        A list of applets to be ignored in standalone shell mode.  The
+        format is the same as that used by the BB_OVERRIDE_APPLETS
+        environment variable.  BB_OVERRIDE_APPLETS is checked first, if it
+        allows the applet and this list is non-empty it is checked too.
+
 comment 'Build Options'
 
 config STATIC
diff --git a/configs/mingw32_defconfig b/configs/mingw32_defconfig
index 3a21dfae6..ee01330d1 100644
--- a/configs/mingw32_defconfig
+++ b/configs/mingw32_defconfig
@@ -1,7 +1,7 @@
 #
 # Automatically generated make config: don't edit
 # Busybox version: 1.37.0.git
-# Wed Sep 20 08:30:38 2023
+# Sat Dec  9 09:38:58 2023
 #
 CONFIG_HAVE_DOT_CONFIG=y
 # CONFIG_PLATFORM_POSIX is not set
@@ -61,6 +61,7 @@ CONFIG_FEATURE_EURO=y
 CONFIG_TERMINAL_MODE=5
 CONFIG_FEATURE_IMPROVED_COLOUR_MAPPING=y
 CONFIG_FEATURE_EXTRA_FILE_DATA=y
+CONFIG_OVERRIDE_APPLETS=""
 
 #
 # Build Options
diff --git a/configs/mingw64_defconfig b/configs/mingw64_defconfig
index 8b993460f..3fed1c99b 100644
--- a/configs/mingw64_defconfig
+++ b/configs/mingw64_defconfig
@@ -1,7 +1,7 @@
 #
 # Automatically generated make config: don't edit
 # Busybox version: 1.37.0.git
-# Wed Sep 20 08:30:38 2023
+# Sat Dec  9 09:38:58 2023
 #
 CONFIG_HAVE_DOT_CONFIG=y
 # CONFIG_PLATFORM_POSIX is not set
@@ -61,6 +61,7 @@ CONFIG_FEATURE_EURO=y
 CONFIG_TERMINAL_MODE=5
 CONFIG_FEATURE_IMPROVED_COLOUR_MAPPING=y
 CONFIG_FEATURE_EXTRA_FILE_DATA=y
+CONFIG_OVERRIDE_APPLETS=""
 
 #
 # Build Options
diff --git a/configs/mingw64u_defconfig b/configs/mingw64u_defconfig
index a7428d1d2..f3391a206 100644
--- a/configs/mingw64u_defconfig
+++ b/configs/mingw64u_defconfig
@@ -1,7 +1,7 @@
 #
 # Automatically generated make config: don't edit
 # Busybox version: 1.37.0.git
-# Wed Sep 20 08:30:38 2023
+# Sat Dec  9 09:38:58 2023
 #
 CONFIG_HAVE_DOT_CONFIG=y
 # CONFIG_PLATFORM_POSIX is not set
@@ -61,6 +61,7 @@ CONFIG_FEATURE_UTF8_OUTPUT=y
 CONFIG_TERMINAL_MODE=5
 CONFIG_FEATURE_IMPROVED_COLOUR_MAPPING=y
 CONFIG_FEATURE_EXTRA_FILE_DATA=y
+CONFIG_OVERRIDE_APPLETS=""
 
 #
 # Build Options
diff --git a/libbb/appletlib.c b/libbb/appletlib.c
index 6b610743a..3c9cebf1e 100644
--- a/libbb/appletlib.c
+++ b/libbb/appletlib.c
@@ -282,12 +282,11 @@ static int external_exists(const char *name)
         return ret != NULL;
 }
 
-int FAST_FUNC is_applet_preferred(const char *name)
+static int is_applet_preferred_by_var(const char *name, const char *var)
 {
-        const char *var, *s, *sep;
+        const char *s, *sep;
         size_t len;
 
-        var = getenv(BB_OVERRIDE_APPLETS);
         if (var && *var) {
                 /* '-' disables all applets */
                 if (var[0] == '-' && var[1] == '\0')
@@ -319,6 +318,14 @@ int FAST_FUNC is_applet_preferred(const char *name)
         }
         return TRUE;
 }
+
+int FAST_FUNC is_applet_preferred(const char *name)
+{
+        int ret = is_applet_preferred_by_var(name, getenv(BB_OVERRIDE_APPLETS));
+        if (sizeof(CONFIG_OVERRIDE_APPLETS) > 1 && ret)
+                ret = is_applet_preferred_by_var(name, CONFIG_OVERRIDE_APPLETS);
+        return ret;
+}
 #endif