On Thu, Mar 29, 2018 at 4:19 AM, Ulf Magnusson <ulfalizer@xxxxxxxxx> wrote: > I've been kinda busy lately, so that's why I disappeared. > > I'll try to go over this patchset in more detail over the weekend. > > On Tue, Mar 27, 2018 at 7:29 AM, Masahiro Yamada > <yamada.masahiro@xxxxxxxxxxxxx> wrote: >> To get an environment value, Kconfig needs to define a symbol using >> "option env=" syntax. It is tedious to add a config entry for each >> environment given that we need more environments such as 'CC', 'AS', >> 'srctree' etc. to evaluate the compiler capability in Kconfig. >> >> Adding '$' to symbols is weird. Kconfig can reference symbols directly >> like this: >> >> config FOO >> string >> default BAR >> >> So, I want to use the following syntax to get environment 'BAR' from >> the system: >> >> config FOO >> string >> default $BAR >> >> Looking at the code, the symbols prefixed with 'S' are expanded by: >> - conf_expand_value() >> This is used to expand 'arch/$ARCH/defconfig' and 'defconfig_list' >> - expand_string_value() >> This is used to expand strings in 'source' and 'mainmenu' >> >> All of them are fixed values independent of user configuration. So, >> this kind of syntax should be moved to simply take the environment. >> >> This change makes the code much cleaner. The bounce symbols 'SRCARCH', >> 'ARCH', 'SUBARCH', 'KERNELVERSION' are gone. >> >> sym_init() hard-coding 'UNAME_RELEASE' is also gone. 'UNAME_RELEASE' >> should be be given from the environment. >> >> ARCH_DEFCONFIG is a normal symbol, so it should be simply referenced >> by 'default ARCH_DEFCONFIG'. >> >> The environments are expanding in the lexer; when '$' is encountered, >> it is expanded, and resulted strings are pushed back to the input >> stream. This makes the implementation simpler. >> >> For example, the following code works. >> >> [Example code] >> >> config TOOLCHAIN_LIST >> string >> default "My tools: CC=$CC, AS=$AS, CPP=$CPP" >> >> [Result] >> >> $ make -s alldefconfig && tail -n 1 .config >> CONFIG_TOOLCHAIN_LIST="My tools: CC=gcc, AS=as, CPP=gcc -E" >> >> Signed-off-by: Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> >> --- >> >> I tested all 'make *config' for arch architectures. >> I confirmed this commit still produced the same result >> (by my kconfig test tool). >> >> >> Changes in v2: >> - Move the string expansion to the lexer phase. >> - Split environment helpers to env.c >> >> Documentation/kbuild/kconfig-language.txt | 8 --- >> Kconfig | 4 -- >> Makefile | 3 +- >> arch/sh/Kconfig | 4 +- >> arch/sparc/Kconfig | 4 +- >> arch/tile/Kconfig | 2 +- >> arch/um/Kconfig.common | 4 -- >> arch/x86/Kconfig | 4 +- >> arch/x86/um/Kconfig | 4 +- >> init/Kconfig | 10 +--- >> scripts/kconfig/confdata.c | 31 +--------- >> scripts/kconfig/env.c | 95 +++++++++++++++++++++++++++++++ >> scripts/kconfig/kconf_id.c | 1 - >> scripts/kconfig/lkc.h | 8 +-- >> scripts/kconfig/menu.c | 3 - >> scripts/kconfig/symbol.c | 56 ------------------ >> scripts/kconfig/util.c | 75 ++++++++---------------- >> scripts/kconfig/zconf.l | 20 ++++++- >> scripts/kconfig/zconf.y | 2 +- >> 19 files changed, 158 insertions(+), 180 deletions(-) >> create mode 100644 scripts/kconfig/env.c >> >> diff --git a/Documentation/kbuild/kconfig-language.txt b/Documentation/kbuild/kconfig-language.txt >> index f5b9493..0e966e8 100644 >> --- a/Documentation/kbuild/kconfig-language.txt >> +++ b/Documentation/kbuild/kconfig-language.txt >> @@ -198,14 +198,6 @@ applicable everywhere (see syntax). >> enables the third modular state for all config symbols. >> At most one symbol may have the "modules" option set. >> >> - - "env"=<value> >> - This imports the environment variable into Kconfig. It behaves like >> - a default, except that the value comes from the environment, this >> - also means that the behaviour when mixing it with normal defaults is >> - undefined at this point. The symbol is currently not exported back >> - to the build environment (if this is desired, it can be done via >> - another symbol). >> - >> - "allnoconfig_y" >> This declares the symbol as one that should have the value y when >> using "allnoconfig". Used for symbols that hide other symbols. >> diff --git a/Kconfig b/Kconfig >> index 8c4c1cb..e6ece5b 100644 >> --- a/Kconfig >> +++ b/Kconfig >> @@ -5,8 +5,4 @@ >> # >> mainmenu "Linux/$ARCH $KERNELVERSION Kernel Configuration" >> >> -config SRCARCH >> - string >> - option env="SRCARCH" >> - >> source "arch/$SRCARCH/Kconfig" >> diff --git a/Makefile b/Makefile >> index 5c395ed..4ae1486 100644 >> --- a/Makefile >> +++ b/Makefile >> @@ -284,7 +284,8 @@ include scripts/Kbuild.include >> # Read KERNELRELEASE from include/config/kernel.release (if it exists) >> KERNELRELEASE = $(shell cat include/config/kernel.release 2> /dev/null) >> KERNELVERSION = $(VERSION)$(if $(PATCHLEVEL),.$(PATCHLEVEL)$(if $(SUBLEVEL),.$(SUBLEVEL)))$(EXTRAVERSION) >> -export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION >> +UNAME_RELEASE := $(shell uname --release) >> +export VERSION PATCHLEVEL SUBLEVEL KERNELRELEASE KERNELVERSION UNAME_RELEASE >> >> # SUBARCH tells the usermode build what the underlying arch is. That is set >> # first, and if a usermode build is happening, the "ARCH=um" on the command >> diff --git a/arch/sh/Kconfig b/arch/sh/Kconfig >> index 97fe293..14f3ef1 100644 >> --- a/arch/sh/Kconfig >> +++ b/arch/sh/Kconfig >> @@ -57,7 +57,7 @@ config SUPERH >> <http://www.linux-sh.org/>. >> >> config SUPERH32 >> - def_bool ARCH = "sh" >> + def_bool "$ARCH" = "sh" >> select HAVE_KPROBES >> select HAVE_KRETPROBES >> select HAVE_IOREMAP_PROT if MMU && !X2TLB >> @@ -76,7 +76,7 @@ config SUPERH32 >> select HAVE_CC_STACKPROTECTOR >> >> config SUPERH64 >> - def_bool ARCH = "sh64" >> + def_bool "$ARCH" = "sh64" >> select HAVE_EXIT_THREAD >> select KALLSYMS >> >> diff --git a/arch/sparc/Kconfig b/arch/sparc/Kconfig >> index 8767e45..86b852e 100644 >> --- a/arch/sparc/Kconfig >> +++ b/arch/sparc/Kconfig >> @@ -1,6 +1,6 @@ >> config 64BIT >> - bool "64-bit kernel" if ARCH = "sparc" >> - default ARCH = "sparc64" >> + bool "64-bit kernel" if "$ARCH" = "sparc" >> + default "$ARCH" = "sparc64" >> help >> SPARC is a family of RISC microprocessors designed and marketed by >> Sun Microsystems, incorporated. They are very widely found in Sun >> diff --git a/arch/tile/Kconfig b/arch/tile/Kconfig >> index ef9d403..acc2182 100644 >> --- a/arch/tile/Kconfig >> +++ b/arch/tile/Kconfig >> @@ -119,7 +119,7 @@ config HVC_TILE >> # Building with ARCH=tilegx (or ARCH=tile) implies using the >> # 64-bit TILE-Gx toolchain, so force CONFIG_TILEGX on. >> config TILEGX >> - def_bool ARCH != "tilepro" >> + def_bool "$ARCH" != "tilepro" >> select ARCH_SUPPORTS_ATOMIC_RMW >> select GENERIC_IRQ_LEGACY_ALLOC_HWIRQ >> select HAVE_ARCH_JUMP_LABEL >> diff --git a/arch/um/Kconfig.common b/arch/um/Kconfig.common >> index c68add8..07f84c8 100644 >> --- a/arch/um/Kconfig.common >> +++ b/arch/um/Kconfig.common >> @@ -54,10 +54,6 @@ config HZ >> int >> default 100 >> >> -config SUBARCH >> - string >> - option env="SUBARCH" >> - >> config NR_CPUS >> int >> range 1 1 >> diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig >> index 0fa71a7..986fb0a 100644 >> --- a/arch/x86/Kconfig >> +++ b/arch/x86/Kconfig >> @@ -1,8 +1,8 @@ >> # SPDX-License-Identifier: GPL-2.0 >> # Select 32 or 64 bit >> config 64BIT >> - bool "64-bit kernel" if ARCH = "x86" >> - default ARCH != "i386" >> + bool "64-bit kernel" if "$ARCH" = "x86" >> + default "$ARCH" != "i386" >> ---help--- >> Say yes to build a 64-bit kernel - formerly known as x86_64 >> Say no to build a 32-bit kernel - formerly known as i386 >> diff --git a/arch/x86/um/Kconfig b/arch/x86/um/Kconfig >> index 13ed827..d355413 100644 >> --- a/arch/x86/um/Kconfig >> +++ b/arch/x86/um/Kconfig >> @@ -16,8 +16,8 @@ config UML_X86 >> select GENERIC_FIND_FIRST_BIT >> >> config 64BIT >> - bool "64-bit kernel" if SUBARCH = "x86" >> - default SUBARCH != "i386" >> + bool "64-bit kernel" if $SUBARCH = "x86" >> + default $SUBARCH != "i386" >> >> config X86_32 >> def_bool !64BIT >> diff --git a/init/Kconfig b/init/Kconfig >> index df18492..b4814e6 100644 >> --- a/init/Kconfig >> +++ b/init/Kconfig >> @@ -1,11 +1,3 @@ >> -config ARCH >> - string >> - option env="ARCH" >> - >> -config KERNELVERSION >> - string >> - option env="KERNELVERSION" >> - >> config DEFCONFIG_LIST >> string >> depends on !UML >> @@ -13,7 +5,7 @@ config DEFCONFIG_LIST >> default "/lib/modules/$UNAME_RELEASE/.config" >> default "/etc/kernel-config" >> default "/boot/config-$UNAME_RELEASE" >> - default "$ARCH_DEFCONFIG" >> + default ARCH_DEFCONFIG >> default "arch/$ARCH/defconfig" >> >> config CONSTRUCTORS >> diff --git a/scripts/kconfig/confdata.c b/scripts/kconfig/confdata.c >> index df26c7b..98c2014 100644 >> --- a/scripts/kconfig/confdata.c >> +++ b/scripts/kconfig/confdata.c >> @@ -81,39 +81,13 @@ const char *conf_get_autoconfig_name(void) >> return name ? name : "include/config/auto.conf"; >> } >> >> -static char *conf_expand_value(const char *in) >> -{ >> - struct symbol *sym; >> - const char *src; >> - static char res_value[SYMBOL_MAXLENGTH]; >> - char *dst, name[SYMBOL_MAXLENGTH]; >> - >> - res_value[0] = 0; >> - dst = name; >> - while ((src = strchr(in, '$'))) { >> - strncat(res_value, in, src - in); >> - src++; >> - dst = name; >> - while (isalnum(*src) || *src == '_') >> - *dst++ = *src++; >> - *dst = 0; >> - sym = sym_lookup(name, 0); >> - sym_calc_value(sym); >> - strcat(res_value, sym_get_string_value(sym)); >> - in = src; >> - } >> - strcat(res_value, in); >> - >> - return res_value; >> -} >> - >> char *conf_get_default_confname(void) >> { >> struct stat buf; >> static char fullname[PATH_MAX+1]; >> char *env, *name; >> >> - name = conf_expand_value(conf_defname); >> + name = expand_string_value(conf_defname); >> env = getenv(SRCTREE); >> if (env) { >> sprintf(fullname, "%s/%s", env, name); >> @@ -274,7 +248,8 @@ int conf_read_simple(const char *name, int def) >> if (expr_calc_value(prop->visible.expr) == no || >> prop->expr->type != E_SYMBOL) >> continue; >> - name = conf_expand_value(prop->expr->left.sym->name); >> + sym_calc_value(prop->expr->left.sym); >> + name = sym_get_string_value(prop->expr->left.sym); >> in = zconf_fopen(name); >> if (in) { >> conf_message(_("using defaults found in %s"), >> diff --git a/scripts/kconfig/env.c b/scripts/kconfig/env.c >> new file mode 100644 >> index 0000000..9702f5c >> --- /dev/null >> +++ b/scripts/kconfig/env.c >> @@ -0,0 +1,95 @@ >> +// SPDX-License-Identifier: GPL-2.0 >> +// >> +// Copyright (C) 2018 Masahiro Yamada <yamada.masahiro@xxxxxxxxxxxxx> >> + >> +static LIST_HEAD(env_list); >> + >> +struct env { >> + char *name; >> + char *value; >> + struct list_head node; >> +}; >> + >> +static struct env *env_list_lookup(const char *name) >> +{ >> + struct env *e; >> + >> + list_for_each_entry(e, &env_list, node) { >> + if (!strcmp(name, e->name)) >> + return e; >> + } >> + >> + return NULL; >> +} >> + >> +static void env_list_add(const char *name, const char *value) >> +{ >> + struct env *e; >> + >> + e = xmalloc(sizeof(*e)); >> + e->name = xstrdup(name); >> + e->value = xstrdup(value); >> + >> + list_add_tail(&e->node, &env_list); >> +} >> + >> +static void env_list_del(struct env *e) >> +{ >> + list_del(&e->node); >> + free(e->name); >> + free(e->value); >> + free(e); >> +} >> + >> +/* the returned pointer must be freed when done */ >> +static char *env_expand(const char *name) >> +{ >> + struct env *e; >> + const char *value; >> + >> + e = env_list_lookup(name); >> + if (e) >> + return xstrdup(e->value); >> + >> + value = getenv(name); >> + if (!value) { >> + fprintf(stderr, "environment variable \"%s\" undefined\n", name); >> + value = ""; >> + } >> + >> + /* >> + * we need to remember all referenced environments. >> + * They will be written out to include/config/auto.conf.cmd >> + */ >> + env_list_add(name, value); >> + >> + return xstrdup(value); >> +} >> + >> +/* works like env_expand, but 'name' does not need to be null-terminated */ >> +char *env_expand_n(const char *name, size_t n) >> +{ >> + char *tmp, *res; >> + >> + tmp = xmalloc(n + 1); >> + memcpy(tmp, name, n); >> + *(tmp + n) = '\0'; >> + >> + res = env_expand(tmp); >> + >> + free(tmp); >> + >> + return res; >> +} >> + >> +void env_write_dep(FILE *f, const char *autoconfig_name) >> +{ >> + struct env *env, *tmp; >> + >> + list_for_each_entry_safe(env, tmp, &env_list, node) { >> + fprintf(f, "ifneq \"$(%s)\" \"%s\"\n", env->name, env->value); >> + fprintf(f, "%s: FORCE\n", autoconfig_name); >> + fprintf(f, "endif\n"); >> + env_list_del(env); >> + } >> +} >> diff --git a/scripts/kconfig/kconf_id.c b/scripts/kconfig/kconf_id.c >> index 3ea9c5f..b3e0ea0 100644 >> --- a/scripts/kconfig/kconf_id.c >> +++ b/scripts/kconfig/kconf_id.c >> @@ -32,7 +32,6 @@ static struct kconf_id kconf_id_array[] = { >> { "on", T_ON, TF_PARAM }, >> { "modules", T_OPT_MODULES, TF_OPTION }, >> { "defconfig_list", T_OPT_DEFCONFIG_LIST, TF_OPTION }, >> - { "env", T_OPT_ENV, TF_OPTION }, >> { "allnoconfig_y", T_OPT_ALLNOCONFIG_Y, TF_OPTION }, >> }; >> >> diff --git a/scripts/kconfig/lkc.h b/scripts/kconfig/lkc.h >> index c8d9e55..03d007f 100644 >> --- a/scripts/kconfig/lkc.h >> +++ b/scripts/kconfig/lkc.h >> @@ -58,7 +58,6 @@ enum conf_def_mode { >> >> #define T_OPT_MODULES 1 >> #define T_OPT_DEFCONFIG_LIST 2 >> -#define T_OPT_ENV 3 >> #define T_OPT_ALLNOCONFIG_Y 4 >> >> struct kconf_id { >> @@ -95,6 +94,10 @@ static inline void xfwrite(const void *str, size_t len, size_t count, FILE *out) >> fprintf(stderr, "Error in writing or end of file.\n"); >> } >> >> +/* env.c */ >> +char *env_expand_n(const char *name, size_t n); >> +void env_write_dep(FILE *f, const char *auto_conf_name); >> + >> /* menu.c */ >> void _menu_init(void); >> void menu_warn(struct menu *menu, const char *fmt, ...); >> @@ -135,9 +138,6 @@ void str_printf(struct gstr *gs, const char *fmt, ...); >> const char *str_get(struct gstr *gs); >> >> /* symbol.c */ >> -extern struct expr *sym_env_list; >> - >> -void sym_init(void); >> void sym_clear_all_valid(void); >> struct symbol *sym_choice_default(struct symbol *sym); >> const char *sym_get_string_default(struct symbol *sym); >> diff --git a/scripts/kconfig/menu.c b/scripts/kconfig/menu.c >> index 5c5c137..8148305 100644 >> --- a/scripts/kconfig/menu.c >> +++ b/scripts/kconfig/menu.c >> @@ -214,9 +214,6 @@ void menu_add_option(int token, char *arg) >> zconf_error("trying to redefine defconfig symbol"); >> sym_defconfig_list->flags |= SYMBOL_AUTO; >> break; >> - case T_OPT_ENV: >> - prop_add_env(arg); >> - break; >> case T_OPT_ALLNOCONFIG_Y: >> current_entry->sym->flags |= SYMBOL_ALLNOCONFIG_Y; >> break; >> diff --git a/scripts/kconfig/symbol.c b/scripts/kconfig/symbol.c >> index 03143b2..7c9a88e 100644 >> --- a/scripts/kconfig/symbol.c >> +++ b/scripts/kconfig/symbol.c >> @@ -33,33 +33,6 @@ struct symbol *sym_defconfig_list; >> struct symbol *modules_sym; >> tristate modules_val; >> >> -struct expr *sym_env_list; >> - >> -static void sym_add_default(struct symbol *sym, const char *def) >> -{ >> - struct property *prop = prop_alloc(P_DEFAULT, sym); >> - >> - prop->expr = expr_alloc_symbol(sym_lookup(def, SYMBOL_CONST)); >> -} >> - >> -void sym_init(void) >> -{ >> - struct symbol *sym; >> - struct utsname uts; >> - static bool inited = false; >> - >> - if (inited) >> - return; >> - inited = true; >> - >> - uname(&uts); >> - >> - sym = sym_lookup("UNAME_RELEASE", 0); >> - sym->type = S_STRING; >> - sym->flags |= SYMBOL_AUTO; >> - sym_add_default(sym, uts.release); >> -} >> - >> enum symbol_type sym_get_type(struct symbol *sym) >> { >> enum symbol_type type = sym->type; >> @@ -1348,32 +1321,3 @@ const char *prop_get_type_name(enum prop_type type) >> } >> return "unknown"; >> } >> - >> -static void prop_add_env(const char *env) >> -{ >> - struct symbol *sym, *sym2; >> - struct property *prop; >> - char *p; >> - >> - sym = current_entry->sym; >> - sym->flags |= SYMBOL_AUTO; >> - for_all_properties(sym, prop, P_ENV) { >> - sym2 = prop_get_symbol(prop); >> - if (strcmp(sym2->name, env)) >> - menu_warn(current_entry, "redefining environment symbol from %s", >> - sym2->name); >> - return; >> - } >> - >> - prop = prop_alloc(P_ENV, sym); >> - prop->expr = expr_alloc_symbol(sym_lookup(env, SYMBOL_CONST)); >> - >> - sym_env_list = expr_alloc_one(E_LIST, sym_env_list); >> - sym_env_list->right.sym = sym; >> - >> - p = getenv(env); >> - if (p) >> - sym_add_default(sym, p); >> - else >> - menu_warn(current_entry, "environment variable %s undefined", env); >> -} >> diff --git a/scripts/kconfig/util.c b/scripts/kconfig/util.c >> index 22201a4..136e497 100644 >> --- a/scripts/kconfig/util.c >> +++ b/scripts/kconfig/util.c >> @@ -8,16 +8,18 @@ >> #include <stdarg.h> >> #include <stdlib.h> >> #include <string.h> >> + >> +#include "list.h" >> #include "lkc.h" >> >> /* >> - * Expand symbol's names embedded in the string given in argument. Symbols' >> - * name to be expanded shall be prefixed by a '$'. Unknown symbol expands to >> + * Expand environments embedded in the string given in argument. Environments >> + * to be expanded shall be prefixed by a '$'. Unknown environment expands to >> * the empty string. >> */ >> char *expand_string_value(const char *in) >> { >> - const char *src; >> + const char *p, *q; >> char *res; >> size_t reslen; >> >> @@ -25,39 +27,28 @@ char *expand_string_value(const char *in) >> * Note: 'in' might come from a token that's about to be >> * freed, so make sure to always allocate a new string >> */ >> - reslen = strlen(in) + 1; >> - res = xmalloc(reslen); >> - res[0] = '\0'; >> - >> - while ((src = strchr(in, '$'))) { >> - char *p, name[SYMBOL_MAXLENGTH]; >> - const char *symval = ""; >> - struct symbol *sym; >> - size_t newlen; >> - >> - strncat(res, in, src - in); >> - src++; >> - >> - p = name; >> - while (isalnum(*src) || *src == '_') >> - *p++ = *src++; >> - *p = '\0'; >> - >> - sym = sym_find(name); >> - if (sym != NULL) { >> - sym_calc_value(sym); >> - symval = sym_get_string_value(sym); >> - } >> + res = xmalloc(1); >> + *res = '\0'; >> >> - newlen = strlen(res) + strlen(symval) + strlen(src) + 1; >> - if (newlen > reslen) { >> - reslen = newlen; >> - res = xrealloc(res, reslen); >> - } >> + while ((p = strchr(in, '$'))) { >> + char *new; >> + >> + q = p + 1; >> + while (isalnum(*q) || *q == '_') >> + q++; >> >> - strcat(res, symval); >> - in = src; >> + new = env_expand_n(p + 1, q - p - 1); >> + >> + reslen = strlen(res) + (p - in) + strlen(new) + 1; >> + res = xrealloc(res, reslen); >> + strncat(res, in, p - in); >> + strcat(res, new); >> + free(new); >> + in = q; >> } >> + >> + reslen = strlen(res) + strlen(in) + 1; >> + res = xrealloc(res, reslen); >> strcat(res, in); >> >> return res; >> @@ -87,8 +78,6 @@ struct file *file_lookup(const char *name) >> /* write a dependency file as used by kbuild to track dependencies */ >> int file_write_dep(const char *name) >> { >> - struct symbol *sym, *env_sym; >> - struct expr *e; >> struct file *file; >> FILE *out; >> >> @@ -107,21 +96,7 @@ int file_write_dep(const char *name) >> fprintf(out, "\n%s: \\\n" >> "\t$(deps_config)\n\n", conf_get_autoconfig_name()); >> >> - expr_list_for_each_sym(sym_env_list, e, sym) { >> - struct property *prop; >> - const char *value; >> - >> - prop = sym_get_env_prop(sym); >> - env_sym = prop_get_symbol(prop); >> - if (!env_sym) >> - continue; >> - value = getenv(env_sym->name); >> - if (!value) >> - value = ""; >> - fprintf(out, "ifneq \"$(%s)\" \"%s\"\n", env_sym->name, value); >> - fprintf(out, "%s: FORCE\n", conf_get_autoconfig_name()); >> - fprintf(out, "endif\n"); >> - } >> + env_write_dep(out, conf_get_autoconfig_name()); >> >> fprintf(out, "\n$(deps_config): ;\n"); >> fclose(out); >> diff --git a/scripts/kconfig/zconf.l b/scripts/kconfig/zconf.l >> index 045093d..551ca47 100644 >> --- a/scripts/kconfig/zconf.l >> +++ b/scripts/kconfig/zconf.l >> @@ -35,6 +35,7 @@ struct buffer *current_buf; >> >> static int last_ts, first_ts; >> >> +static void expand_string(const char *in); >> static void zconf_endhelp(void); >> static void zconf_endfile(void); >> >> @@ -120,6 +121,7 @@ n [A-Za-z0-9_-] >> } >> >> <PARAM>{ >> + "$".* expand_string(yytext); >> "&&" return T_AND; >> "||" return T_OR; >> "(" return T_OPEN_PAREN; >> @@ -157,12 +159,13 @@ n [A-Za-z0-9_-] >> } >> >> <STRING>{ >> - [^'"\\\n]+/\n { >> + "$".* expand_string(yytext); >> + [^$'"\\\n]+/\n { >> append_string(yytext, yyleng); >> yylval.string = text; >> return T_WORD_QUOTE; >> } >> - [^'"\\\n]+ { >> + [^$'"\\\n]+ { >> append_string(yytext, yyleng); >> } >> \\.?/\n { >> @@ -249,6 +252,19 @@ n [A-Za-z0-9_-] >> } >> >> %% >> +static void expand_string(const char *in) >> +{ >> + char *p, *q; >> + >> + p = expand_string_value(in); >> + >> + q = p + strlen(p); >> + while (q > p) >> + unput(*--q); >> + >> + free(p); >> +} >> + > > I like the simplicity of this approach, but I suspect it might be too simple. > > For example, the following breaks with a syntax error if $ENV has any > double quotes in its value: > > config FOO > string "foo" > default "$ENV" > > The following will only work as expected if $ENV expands to a valid > Kconfig symbol name. If it doesn't, random stuff will happen (most > likely a syntax error). > > config FOO > string "foo" > default $ENV > > The reason it works if $ENV expands to a valid symbol name is that > undefined symbols get their name as their (string) value. If the > symbol happens to be defined, it will be referenced, which seems > confusing too. > > In general, that reinterpretation of expanded values feels a bit icky > to me, and as something that might add complexity to Kconfig for > little value. If $ENV outside of quotes absolutely must be supported, > I think it should be a shorthand for "$ENV" (which means "constant > value" in Kconfig speak). If you want something as general as the C preprocessor (which I think would be overkill and complexity land), then it seems kinda weird to limit it to certain Kconfig contexts as well: Right now you'd be able to output arbitrary tokens inside an expression, but you couldn't do something like generate a 'default X if Y'. Cheers, Ulf -- To unsubscribe from this list: send the line "unsubscribe linux-kbuild" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
