From 9ca656b14945ec8462dc529ef5dc7662cce08296 Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Wed, 10 Jun 2009 13:39:35 +0200 Subject: [PATCH] hush: add HUSH_BASH_COMPAT, make [[ special handling depend on it Signed-off-by: Denys Vlasenko --- shell/Config.in | 13 ++++++----- shell/hush.c | 58 +++++++++++++++++++++++++++++-------------------- 2 files changed, 41 insertions(+), 30 deletions(-) diff --git a/shell/Config.in b/shell/Config.in index ee56d89f3..126dba8e5 100644 --- a/shell/Config.in +++ b/shell/Config.in @@ -43,9 +43,6 @@ config ASH shell (by Herbert Xu), which was created by porting the 'ash' shell (written by Kenneth Almquist) from NetBSD. -comment "Ash Shell Options" - depends on ASH - config ASH_BASH_COMPAT bool "bash-compatible extensions" default y @@ -169,6 +166,13 @@ config HUSH It does not handle select, aliases, brace expansion, tilde expansion, &>file and >&file redirection of stdout+stderr. +config HUSH_BASH_COMPAT + bool "bash-compatible extensions" + default y + depends on HUSH + help + Enable bash-compatible extensions. + config HUSH_HELP bool "help builtin" default n @@ -268,9 +272,6 @@ config MSH # It uses only vfork, so it can be used on uClinux systems. -comment "Bourne Shell Options" - depends on MSH || LASH || HUSH || ASH - config SH_MATH_SUPPORT bool "POSIX math support" default y diff --git a/shell/hush.c b/shell/hush.c index c9962e33b..54ab78b27 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -42,11 +42,18 @@ * <(list) and >(list) Process Substitution * Tilde Expansion * - * Bash stuff (maybe optionally enable?): + * Bash stuff (optionally enabled): * &> and >& redirection of stdout+stderr * Brace Expansion * reserved words: [[ ]] function select * substrings ${var:1:5} + * let EXPR [EXPR...] + * Each EXPR is an arithmetic expression (ARITHMETIC EVALUATION) + * If the last arg evaluates to 0, let returns 1; 0 otherwise. + * NB: let `echo 'a=a + 1'` - error (IOW: multi-word expansion is used) + * ((EXPR)) + * The EXPR is evaluated according to ARITHMETIC EVALUATION. + * This is exactly equivalent to let "expression". * * TODOs: * grep for "TODO" and fix (some of them are easy) @@ -59,7 +66,7 @@ * $ ls i=`echo 'a b'` # ls has two args: "i=a" and "b" * ls: cannot access i=a: No such file or directory * ls: cannot access b: No such file or directory - * Note1: same applies to local builtin when we'll have it. + * Note1: same applies to local builtin. * Note2: bash 3.2.33(1) does this only if export word itself * is not quoted: * $ export i=`echo 'aaa bbb'`; echo "$i" @@ -299,28 +306,11 @@ struct command { smallint cmd_type; /* CMD_xxx */ #define CMD_NORMAL 0 #define CMD_SUBSHELL 1 + /* used for "[[ EXPR ]]" */ -#define CMD_SINGLEWORD_NOGLOB 2 -/* used for "export noglob=* glob* a=`echo a b`" */ -/* #define CMD_SINGLEWORD_NOGLOB_COND 3 */ -// It is hard to implement correctly, adds significant amounts of tricky code, -// and all this only useful for really obscure export statements -// almost nobody would use anyway. #ifdef CMD_SINGLEWORD_NOGLOB_COND -// guard the code which implement it, but I have doubts it works -// in all cases (especially with mixed globbed/non-globbed arguments) -#if ENABLE_HUSH_FUNCTIONS -# define CMD_FUNCDEF 4 -#endif -//TODO -//#define CMD_ARITH - let EXPR, ((EXPR)) -//let EXPR [EXPR...] -// Each EXPR is an arithmetic expression to be evaluated (ARITHMETIC EVALUATION) -// If the last arg evaluates to 0, let returns 1; 0 is returned otherwise. -// NB: let `echo 'a=a + 1'` - error (IOW: multi-word expansion is used) -//((EXPR)) -// The EXPR is evaluated according to ARITHMETIC EVALUATION. -// This is exactly equivalent to let "expression". -//[[ EXPR ]] +#if ENABLE_HUSH_BASH_COMPAT +# define CMD_SINGLEWORD_NOGLOB 2 +#endif // Basically, word splitting and pathname expansion should NOT be performed // Examples: // no word splitting: a="a b"; [[ $a = "a b" ]]; echo $? should print "0" @@ -330,6 +320,18 @@ struct command { // =~ regexp match // Apart from the above, [[ expr ]] should work as [ expr ] +/* used for "export noglob=* glob* a=`echo a b`" */ +/*#define CMD_SINGLEWORD_NOGLOB_COND 3 */ +// It is hard to implement correctly, it adds significant amounts of tricky code, +// and all this is only useful for really obscure export statements +// almost nobody would use anyway. #ifdef CMD_SINGLEWORD_NOGLOB_COND +// guards the code which implements it, but I have doubts it works +// in all cases (especially with mixed globbed/non-globbed arguments) + +#if ENABLE_HUSH_FUNCTIONS +# define CMD_FUNCDEF 3 +#endif + /* if non-NULL, this "command" is { list }, ( list ), or a compound statement */ struct pipe *group; #if !BB_MMU @@ -2484,10 +2486,12 @@ static char **expand_strvec_to_strvec(char **argv) return expand_variables(argv, 0x100); } +#if ENABLE_HUSH_BASH_COMPAT static char **expand_strvec_to_strvec_singleword_noglob(char **argv) { return expand_variables(argv, 0x80); } +#endif #ifdef CMD_SINGLEWORD_NOGLOB_COND static char **expand_strvec_to_strvec_singleword_noglob_cond(char **argv) @@ -3838,9 +3842,12 @@ static int run_pipe(struct pipe *pi) } /* Expand the rest into (possibly) many strings each */ - if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) { + if (0) {} +#if ENABLE_HUSH_BASH_COMPAT + else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB) { argv_expanded = expand_strvec_to_strvec_singleword_noglob(argv + command->assignment_cnt); } +#endif #ifdef CMD_SINGLEWORD_NOGLOB_COND else if (command->cmd_type == CMD_SINGLEWORD_NOGLOB_COND) { argv_expanded = expand_strvec_to_strvec_singleword_noglob_cond(argv + command->assignment_cnt); @@ -4094,6 +4101,7 @@ static void debug_print_tree(struct pipe *pi, int lvl) static const char *const CMDTYPE[] = { "{}", "()", + "[noglob]", #if ENABLE_HUSH_FUNCTIONS "func()", #endif @@ -4833,10 +4841,12 @@ static int done_word(o_string *word, struct parse_context *ctx) command->cmd_type = CMD_SINGLEWORD_NOGLOB_COND; } else # endif +# if ENABLE_HUSH_BASH_COMPAT if (strcmp(word->data, "[[") == 0) { command->cmd_type = CMD_SINGLEWORD_NOGLOB; } /* fall through */ +# endif } #endif if (command->group) { -- 2.25.1