buildroot/package/config/patches/03-change-config-option-prefix.patch

---
 confdata.c |   49 +++++++++++++++++++++++--------------------------
 1 file changed, 23 insertions(+), 26 deletions(-)

Index: config.new/confdata.c
===================================================================
--- config.new.orig/confdata.c
+++ config.new/confdata.c
@@ -11,6 +11,7 @@
 #include <string.h>
 #include <time.h>
 #include <unistd.h>
+#include <libgen.h>
 
 #define LKC_DIRECT_LINK
 #include "lkc.h"
@@ -21,7 +22,7 @@
 static const char *conf_filename;
 static int conf_lineno, conf_warnings, conf_unsaved;
 
-const char conf_defname[] = "arch/$ARCH/defconfig";
+const char conf_defname[] = ".defconfig";
 
 static void conf_warning(const char *fmt, ...)
 {
@@ -36,7 +37,7 @@
 
 const char *conf_get_configname(void)
 {
-	char *name = getenv("KCONFIG_CONFIG");
+	char *name = getenv("BUILDROOT_CONFIG");
 
 	return name ? name : ".config";
 }
@@ -222,22 +223,22 @@
 		sym = NULL;
 		switch (line[0]) {
 		case '#':
-			if (memcmp(line + 2, "CONFIG_", 7))
+			if (line[1]!=' ')
 				continue;
-			p = strchr(line + 9, ' ');
+			p = strchr(line + 2, ' ');
 			if (!p)
 				continue;
 			*p++ = 0;
 			if (strncmp(p, "is not set", 10))
 				continue;
 			if (def == S_DEF_USER) {
-				sym = sym_find(line + 9);
+				sym = sym_find(line + 2);
 				if (!sym) {
 					sym_add_change_count(1);
 					break;
 				}
 			} else {
-				sym = sym_lookup(line + 9, 0);
+				sym = sym_lookup(line + 2, 0);
 				if (sym->type == S_UNKNOWN)
 					sym->type = S_BOOLEAN;
 			}
@@ -254,12 +255,8 @@
 				;
 			}
 			break;
-		case 'C':
-			if (memcmp(line, "CONFIG_", 7)) {
-				conf_warning("unexpected data");
-				continue;
-			}
-			p = strchr(line + 7, '=');
+		case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': case 'G': case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U': case 'V': case 'W': case 'X': case 'Y': case 'Z':
+			p = strchr(line, '=');
 			if (!p)
 				continue;
 			*p++ = 0;
@@ -270,13 +267,13 @@
 					*p2 = 0;
 			}
 			if (def == S_DEF_USER) {
-				sym = sym_find(line + 7);
+				sym = sym_find(line);
 				if (!sym) {
 					sym_add_change_count(1);
 					break;
 				}
 			} else {
-				sym = sym_lookup(line + 7, 0);
+				sym = sym_lookup(line, 0);
 				if (sym->type == S_UNKNOWN)
 					sym->type = S_OTHER;
 			}
@@ -405,9 +402,9 @@
 {
 	int l;
 	if (headerfile)
-		fprintf(out, "#define CONFIG_%s \"", name);
+		fprintf(out, "#define %s \"", name);
 	else
-		fprintf(out, "CONFIG_%s=\"", name);
+		fprintf(out, "%s=\"", name);
 
 	while (1) {
 		l = strcspn(str, "\"\\");
@@ -433,13 +430,13 @@
 		switch (sym_get_tristate_value(sym)) {
 		case no:
 			if (write_no)
-				fprintf(out, "# CONFIG_%s is not set\n", sym->name);
+				fprintf(out, "# %s is not set\n", sym->name);
 			break;
 		case mod:
-			fprintf(out, "CONFIG_%s=m\n", sym->name);
+			fprintf(out, "%s=m\n", sym->name);
 			break;
 		case yes:
-			fprintf(out, "CONFIG_%s=y\n", sym->name);
+			fprintf(out, "%s=y\n", sym->name);
 			break;
 		}
 		break;
@@ -449,7 +446,7 @@
 	case S_HEX:
 	case S_INT:
 		str = sym_get_string_value(sym);
-		fprintf(out, "CONFIG_%s=%s\n", sym->name, str);
+		fprintf(out, "%s=%s\n", sym->name, str);
 		break;
 	case S_OTHER:
 	case S_UNKNOWN:
@@ -834,14 +831,14 @@
 			case no:
 				break;
 			case mod:
-				fprintf(tristate, "CONFIG_%s=M\n", sym->name);
-				fprintf(out_h, "#define CONFIG_%s_MODULE 1\n", sym->name);
+				fprintf(tristate, "%s=M\n", sym->name);
+				fprintf(out_h, "#define %s_MODULE 1\n", sym->name);
 				break;
 			case yes:
 				if (sym->type == S_TRISTATE)
-					fprintf(tristate, "CONFIG_%s=Y\n",
+					fprintf(tristate, "%s=Y\n",
 							sym->name);
-				fprintf(out_h, "#define CONFIG_%s 1\n", sym->name);
+				fprintf(out_h, "#define %s 1\n", sym->name);
 				break;
 			}
 			break;
@@ -851,12 +848,12 @@
 		case S_HEX:
 			str = sym_get_string_value(sym);
 			if (str[0] != '0' || (str[1] != 'x' && str[1] != 'X')) {
-				fprintf(out_h, "#define CONFIG_%s 0x%s\n", sym->name, str);
+				fprintf(out_h, "#define %s 0x%s\n", sym->name, str);
 				break;
 			}
 		case S_INT:
 			str = sym_get_string_value(sym);
-			fprintf(out_h, "#define CONFIG_%s %s\n", sym->name, str);
+			fprintf(out_h, "#define %s %s\n", sym->name, str);
 			break;
 		default:
 			break;