diff options
Diffstat (limited to 'shell/hush.c')
| -rw-r--r-- | shell/hush.c | 29 |
1 files changed, 16 insertions, 13 deletions
diff --git a/shell/hush.c b/shell/hush.c index 920d9638c..3faf2b326 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -3800,8 +3800,8 @@ static int encode_string(o_string *as_string, ch = i_getch(input); /* eat next */ if (ch == '\n') goto again; /* skip \<newline> */ - } /* else: ch remains == '\\', and we double it */ - o_addqchr(dest, ch); /* \c if c is s glob char, else just c */ + } /* else: ch remains == '\\', and we double it below: */ + o_addqchr(dest, ch); /* \c if c is a glob char, else just c */ nommu_addchr(as_string, ch); goto again; } @@ -4618,26 +4618,29 @@ static NOINLINE const char *expand_one_var(char **to_be_freed_pp, char *arg, cha * Then var's value is matched to it and matching part removed. */ if (val && val[0]) { + char *t; char *exp_exp_word; char *loc; unsigned scan_flags = pick_scan(exp_op, *exp_word); if (exp_op == *exp_word) /* ## or %% */ exp_word++; -//TODO: avoid xstrdup unless needed -// (see HACK ALERT below for an example) - val = to_be_freed = xstrdup(val); exp_exp_word = encode_then_expand_string(exp_word, /*process_bkslash:*/ 1, /*unbackslash:*/ 1); if (exp_exp_word) exp_word = exp_exp_word; - loc = scan_and_match(to_be_freed, exp_word, scan_flags); + /* HACK ALERT. We depend here on the fact that + * G.global_argv and results of utoa and get_local_var_value + * are actually in writable memory: + * scan_and_match momentarily stores NULs there. */ + t = (char*)val; + loc = scan_and_match(t, exp_word, scan_flags); //bb_error_msg("op:%c str:'%s' pat:'%s' res:'%s'", - // exp_op, to_be_freed, exp_word, loc); + // exp_op, t, exp_word, loc); free(exp_exp_word); if (loc) { /* match was found */ if (scan_flags & SCAN_MATCH_LEFT_HALF) /* #[#] */ - val = loc; + val = loc; /* take right part */ else /* %[%] */ - *loc = '\0'; + val = to_be_freed = xstrndup(val, loc - val); /* left */ } } } @@ -4646,13 +4649,13 @@ static NOINLINE const char *expand_one_var(char **to_be_freed_pp, char *arg, cha /* It's ${var/[/]pattern[/repl]} thing. * Note that in encoded form it has TWO parts: * var/pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL> + * and if // is used, it is encoded as \: + * var\pattern<SPECIAL_VAR_SYMBOL>repl<SPECIAL_VAR_SYMBOL> */ /* Empty variable always gives nothing: */ // "v=''; echo ${v/*/w}" prints "", not "w" if (val && val[0]) { - /* It's ${var/[/]pattern[/repl]} thing */ - /* - * Pattern is taken literally, while + /* pattern uses non-standard expansion. * repl should be unbackslashed and globbed * by the usual expansion rules: * >az; >bz; @@ -7339,7 +7342,7 @@ int hush_main(int argc, char **argv) /* Deal with HUSH_VERSION */ G.shell_ver.flg_export = 1; G.shell_ver.flg_read_only = 1; - /* Code which handles ${var/P/R} needs writable values for all variables, + /* Code which handles ${var<op>...} needs writable values for all variables, * therefore we xstrdup: */ G.shell_ver.varstr = xstrdup(hush_version_str), G.top_var = &G.shell_ver; |