From 6672c8e480994a3d9c928ddedd0542c9ed9b3271 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Fri, 30 Nov 2007 07:29:05 +0000 Subject: test: stop using lots of bss. function old new delta test_main 425 456 +31 t_lex 69 73 +4 syntax 100 104 +4 ptr_to_statics 8 12 +4 t_wp_op 4 - -4 t_wp 4 - -4 ngroups 4 - -4 group_array 4 - -4 binop 590 585 -5 oexpr 104 97 -7 aexpr 101 94 -7 nexpr 831 820 -11 leaving 156 - -156 ------------------------------------------------------------------------------ (add/remove: 0/5 grow/shrink: 4/4 up/down: 43/-202) Total: -159 bytes text data bss dec hex filename 775098 929 9084 785111 bfad7 busybox_old 775107 933 8908 784948 bfa34 busybox_unstripped --- coreutils/test.c | 92 +++++++++++++++++++++++++++++++++++++++----------------- 1 file changed, 64 insertions(+), 28 deletions(-) (limited to 'coreutils') diff --git a/coreutils/test.c b/coreutils/test.c index 0b94100c1..a30a5087d 100644 --- a/coreutils/test.c +++ b/coreutils/test.c @@ -23,7 +23,11 @@ #include "libbb.h" #include -/* This is a NOEXEC applet. Be very careful! */ +/* This is a NOFORK applet. Be very careful! */ + +/* test_main() is called from shells, and we need to be extra careful here. + * This is true regardless of PREFER_APPLETS and STANDALONE_SHELL + * state. */ /* test(1) accepts the following grammar: @@ -85,12 +89,12 @@ enum token { RPAREN, OPERAND }; -#define is_int_op(a) (((unsigned char)((a) - INTEQ)) <= 5) -#define is_str_op(a) (((unsigned char)((a) - STREZ)) <= 5) -#define is_file_op(a) (((unsigned char)((a) - FILNT)) <= 2) +#define is_int_op(a) (((unsigned char)((a) - INTEQ)) <= 5) +#define is_str_op(a) (((unsigned char)((a) - STREZ)) <= 5) +#define is_file_op(a) (((unsigned char)((a) - FILNT)) <= 2) #define is_file_access(a) (((unsigned char)((a) - FILRD)) <= 2) -#define is_file_type(a) (((unsigned char)((a) - FILREG)) <= 5) -#define is_file_bit(a) (((unsigned char)((a) - FILSUID)) <= 2) +#define is_file_type(a) (((unsigned char)((a) - FILREG)) <= 5) +#define is_file_bit(a) (((unsigned char)((a) - FILSUID)) <= 2) enum token_types { UNOP, BINOP, @@ -153,13 +157,33 @@ typedef int64_t arith_t; typedef int arith_t; #endif -/* Cannot eliminate these static data (do the G trick) - * because of test_main usage from other applets */ -static char **t_wp; -static const struct t_op *t_wp_op; -static gid_t *group_array; -static int ngroups; -static jmp_buf leaving; + +/* We try to minimize both static and stack usage. */ +struct statics { + char **t_wp; + const struct t_op *t_wp_op; + gid_t *group_array; + int ngroups; + jmp_buf leaving; +}; + +/* Make it reside in writable memory, yet make compiler understand + * that it is not going to change. */ +static struct statics *const ptr_to_statics __attribute__ ((section (".data"))); + +#define S (*ptr_to_statics) +#define t_wp (S.t_wp ) +#define t_wp_op (S.t_wp_op ) +#define group_array (S.group_array ) +#define ngroups (S.ngroups ) +#define leaving (S.leaving ) + +#define INIT_S() do { \ + (*(struct statics**)&ptr_to_statics) = xzalloc(sizeof(S)); \ +} while (0) +#define DEINIT_S() do { \ + free(ptr_to_statics); \ +} while (0) static arith_t primary(enum token n); @@ -550,9 +574,13 @@ int test_main(int argc, char **argv) argv[argc] = NULL; } + /* We must do DEINIT_S() prior to returning */ + INIT_S(); + res = setjmp(leaving); - if (res) - return res; + if (res) { + goto ret; + } /* resetting ngroups is probably unnecessary. it will * force a new call to getgroups(), which prevents using @@ -565,24 +593,30 @@ int test_main(int argc, char **argv) ngroups = 0; /* Implement special cases from POSIX.2, section 4.62.4 */ - if (argc == 1) - return 1; - if (argc == 2) - return *argv[1] == '\0'; -//assert(argc); + if (argc == 1) { + res = 1; + goto ret; + } + if (argc == 2) { + res = (*argv[1] == '\0'); + goto ret; + } + /* remember if we saw argc==4 which wants *no* '!' test */ _off = argc - 4; - if (_off ? - (LONE_CHAR(argv[1], '!')) - : (argv[1][0] != '!' || argv[1][1] != '\0')) - { - if (argc == 3) - return *argv[2] != '\0'; + if (_off ? (LONE_CHAR(argv[1], '!')) + : (argv[1][0] != '!' || argv[1][1] != '\0') + ) { + if (argc == 3) { + res = (*argv[2] != '\0'); + goto ret; + } t_lex(argv[2 + _off]); if (t_wp_op && t_wp_op->op_type == BINOP) { t_wp = &argv[1 + _off]; - return binop() == _off; + res = (binop() == _off); + goto ret; } } t_wp = &argv[1]; @@ -590,7 +624,9 @@ int test_main(int argc, char **argv) if (*t_wp != NULL && *++t_wp != NULL) { bb_error_msg("%s: unknown operand", *t_wp); - return 2; + res = 2; } + ret: + DEINIT_S(); return res; } -- cgit v1.2.3