eglibc: add support for user provided option groups

Signed-off-by: Arnaud Vrac <avrac@freebox.fr>

config/libc/eglibc.in

@@ -90,3 +90,55 @@ config EGLIBC_CHECKOUT
       
       Note that crosstool-NG will *not* update your working copy, you will
       have to do that yourself.
+
+config EGLIBC_CUSTOM_CONFIG
+    bool
+    prompt "Use custom configuration file"
+    default n
+    help
+      Use a custom configuration file to disable some features in the eglibc
+      library. The configuration file options are described in detail in the
+      option-groups.def file in the eglibc source directory.
+
+if EGLIBC_CUSTOM_CONFIG
+    config EGLIBC_OPTION_GROUPS_FILE
+        string
+        prompt "Path to the option-groups configuration file"
+        default ""
+        help
+          Path to the option groups configuration file.
+
+    config EGLIBC_BUNDLED_NSS_CONFIG
+        bool
+        prompt "Use bundled NSS config file"
+        default y
+        help
+          Use minimal nsswitch configuration file bundled in eglibc.
+          This option is only meaningful when runtime nss configuration
+          is disabled in the option groups file.
+
+    config EGLIBC_NSS_CONFIG_FILE
+        string
+        prompt "Path to the NSS config file"
+        default ""
+        depends on !EGLIBC_BUNDLED_NSS_CONFIG
+        help
+          Path to the nsswitch configuration file
+
+    config EGLIBC_BUNDLED_NSS_FUNCTIONS
+        bool
+        prompt "Use bundled NSS functions file"
+        default y
+        help
+          Use minimal nsswitch functions file bundled in eglibc.
+          This option is only meaningful when runtime nss configuration
+          is disabled in the option groups file.
+
+    config EGLIBC_NSS_FUNCTIONS_FILE
+        string
+        prompt "Path to the NSS functions file"
+        default ""
+        depends on !EGLIBC_BUNDLED_NSS_FUNCTIONS
+        help
+          Path to the nsswitch functions file
+endif

scripts/build/libc/eglibc.sh

@@ -122,9 +122,50 @@ do_libc_extract() {
     return 0
 }
 
-# There is nothing to do for eglibc check config
+# Copy user provided eglibc configuration file if provided
 do_libc_check_config() {
-    :
+    if [ "${CT_EGLIBC_CUSTOM_CONFIG}" != "y" ]; then
+        return 0
+    fi
+
+    CT_DoStep INFO "Checking C library configuration"
+
+    CT_TestOrAbort "You did not provide an eglibc config file!" \
+        -n "${CT_EGLIBC_OPTION_GROUPS_FILE}" -a \
+        -f "${CT_EGLIBC_OPTION_GROUPS_FILE}"
+
+    CT_DoExecLog ALL cp "${CT_EGLIBC_OPTION_GROUPS_FILE}" "${CT_CONFIG_DIR}/eglibc.config"
+
+    # NSS configuration
+    if grep -E '^OPTION_EGLIBC_NSSWITCH[[:space:]]*=[[:space:]]*n' "${CT_EGLIBC_OPTION_GROUPS_FILE}" >/dev/null 2>&1; then
+        CT_DoLog DEBUG "Using fixed-configuration nsswitch facility"
+
+        if [ "${CT_EGLIBC_BUNDLED_NSS_CONFIG}" = "y" ]; then
+            nss_config="${CT_SRC_DIR}/eglibc-${CT_LIBC_VERSION}/nss/fixed-nsswitch.conf"
+        else
+            nss_config="${CT_EGLIBC_NSS_CONFIG_FILE}"
+        fi
+        CT_TestOrAbort "NSS config file not found!" -n "${nss_config}" -a -f "${nss_config}"
+
+        CT_DoExecLog ALL cp "${nss_config}" "${CT_CONFIG_DIR}/nsswitch.config"
+        echo "OPTION_EGLIBC_NSSWITCH_FIXED_CONFIG = ${CT_CONFIG_DIR}/nsswitch.config" \
+            >> "${CT_CONFIG_DIR}/eglibc.config"
+
+        if [ "${CT_EGLIBC_BUNDLED_NSS_FUNCTIONS}" = "y" ]; then
+            nss_functions="${CT_SRC_DIR}/eglibc-${CT_LIBC_VERSION}/nss/fixed-nsswitch.functions"
+        else
+            nss_functions="${CT_EGLIBC_NSS_FUNCTIONS_FILE}"
+        fi
+        CT_TestOrAbort "NSS functions file not found!" -n "${nss_functions}" -a -f "${nss_functions}"
+
+        CT_DoExecLog ALL cp "${nss_functions}" "${CT_CONFIG_DIR}/nsswitch.functions"
+        echo "OPTION_EGLIBC_NSSWITCH_FIXED_FUNCTIONS = ${CT_CONFIG_DIR}/nsswitch.functions" \
+            >> "${CT_CONFIG_DIR}/eglibc.config"
+    else
+        CT_DoLog DEBUG "Using full-blown nsswitch facility"
+    fi
+
+    CT_EndStep
 }
 
 # This function installs the eglibc headers needed to build the core compiler
@@ -143,6 +184,10 @@ do_libc_start_files() {
 
     CT_DoLog EXTRA "Configuring C library"
 
+    if [ "${CT_EGLIBC_CUSTOM_CONFIG}" = "y" ]; then
+        CT_DoExecLog ALL cp "${CT_CONFIG_DIR}/eglibc.config" option-groups.config
+    fi
+
     cross_cc=$(CT_Which "${CT_TARGET}-gcc")
     cross_cxx=$(CT_Which "${CT_TARGET}-g++")
     cross_ar=$(CT_Which "${CT_TARGET}-ar")
@@ -210,6 +255,10 @@ do_libc() {
 
     CT_DoLog EXTRA "Configuring C library"
 
+    if [ "${CT_EGLIBC_CUSTOM_CONFIG}" = "y" ]; then
+        CT_DoExecLog ALL cp "${CT_CONFIG_DIR}/eglibc.config" option-groups.config
+    fi
+
     # Add some default glibc config options if not given by user.
     # We don't need to be conditional on wether the user did set different
     # values, as they CT_LIBC_GLIBC_EXTRA_CONFIG is passed after extra_config