From 74e425407f1cb90df0dba7f1ae3cffa359168967 Mon Sep 17 00:00:00 2001 From: Francis Laniel Date: Fri, 22 Dec 2023 22:02:33 +0100 Subject: [PATCH] cli: hush_modern: Enable variables expansion for modern hush Enables variables expansion for modern hush, both for local and environment variables. So the following commands: foo=bar echo $foo setenv bar foo echo $bar leads to "bar" and "foo" being printed on console output. Signed-off-by: Francis Laniel Reviewed-by: Simon Glass --- common/cli_hush_modern.c | 17 +++++++ common/cli_hush_upstream.c | 91 +++++++++++++++++++++++++++++++++++--- 2 files changed, 103 insertions(+), 5 deletions(-) diff --git a/common/cli_hush_modern.c b/common/cli_hush_modern.c index 626fed089b..15bb1f0d92 100644 --- a/common/cli_hush_modern.c +++ b/common/cli_hush_modern.c @@ -207,6 +207,23 @@ static const char* endofname(const char *name) return name; } +/** + * list_size() - returns the number of elements in char ** before NULL. + * + * Argument must contain NULL to signalize its end. + * + * @list The list to count the number of element. + * @return The number of element in list. + */ +static size_t list_size(char **list) +{ + size_t size; + + for (size = 0; list[size] != NULL; size++); + + return size; +} + struct in_str; static int u_boot_cli_readline(struct in_str *i); diff --git a/common/cli_hush_upstream.c b/common/cli_hush_upstream.c index 4b6ab20f3b..ff4a57c6e3 100644 --- a/common/cli_hush_upstream.c +++ b/common/cli_hush_upstream.c @@ -3485,7 +3485,6 @@ static int o_get_last_ptr(o_string *o, int n) return ((int)(uintptr_t)list[n-1]) + string_start; } -#ifndef __U_BOOT__ /* * Globbing routines. * @@ -3740,8 +3739,10 @@ static int glob_needed(const char *s) */ static int perform_glob(o_string *o, int n) { +#ifndef __U_BOOT__ glob_t globdata; int gr; +#endif /* __U_BOOT__ */ char *pattern; debug_printf_glob("start perform_glob: n:%d o->data:%p\n", n, o->data); @@ -3750,13 +3751,16 @@ static int perform_glob(o_string *o, int n) pattern = o->data + o_get_last_ptr(o, n); debug_printf_glob("glob pattern '%s'\n", pattern); if (!glob_needed(pattern)) { +#ifndef __U_BOOT__ literal: +#endif /* __U_BOOT__ */ /* unbackslash last string in o in place, fix length */ o->length = unbackslash(pattern) - o->data; debug_printf_glob("glob pattern '%s' is literal\n", pattern); return o_save_ptr_helper(o, n); } +#ifndef __U_BOOT__ memset(&globdata, 0, sizeof(globdata)); /* Can't use GLOB_NOCHECK: it does not unescape the string. * If we glob "*.\*" and don't find anything, we need @@ -3792,16 +3796,22 @@ static int perform_glob(o_string *o, int n) if (DEBUG_GLOB) debug_print_list("perform_glob returning", o, n); return n; +#else /* __U_BOOT__ */ + /* + * NOTE We only use perform glob to call unbackslash to remove backslash + * from string once expanded. + * So, it seems OK to return this if no previous return was done. + */ + return o_save_ptr_helper(o, n); +#endif /* __U_BOOT__ */ } -#endif /* !__U_BOOT__ */ #endif /* !HUSH_BRACE_EXPANSION */ /* If o->o_expflags & EXP_FLAG_GLOB, glob the string so far remembered. * Otherwise, just finish current list[] and start new */ static int o_save_ptr(o_string *o, int n) { -#ifndef __U_BOOT__ if (o->o_expflags & EXP_FLAG_GLOB) { /* If o->has_empty_slot, list[n] was already globbed * (if it was requested back then when it was filled) @@ -3809,7 +3819,6 @@ static int o_save_ptr(o_string *o, int n) if (!o->has_empty_slot) return perform_glob(o, n); /* o_save_ptr_helper is inside */ } -#endif /* !__U_BOOT__ */ return o_save_ptr_helper(o, n); } @@ -5455,7 +5464,20 @@ static int parse_dollar(o_string *as_string, nommu_addchr(as_string, ch); if (ch == '}') break; +#ifndef __U_BOOT__ if (!isalnum(ch) && ch != '_') { +#else /* __U_BOOT__ */ + /* + * In several places in U-Boot, we use variable like + * foo# (e.g. serial#), particularly in env. + * So, we need to authorize # to appear inside + * variable name and then expand this variable. + * NOTE Having # in variable name is not permitted in + * upstream hush but expansion will be done (even though + * the result will be empty). + */ + if (!isalnum(ch) && ch != '_' && ch != '#') { +#endif /* __U_BOOT__ */ unsigned end_ch; #ifndef __U_BOOT__ unsigned char last_ch; @@ -7030,7 +7052,20 @@ static NOINLINE int expand_one_var(o_string *output, int n, } #endif /* !__U_BOOT__ */ default: +#ifndef __U_BOOT__ val = get_local_var_value(var); +#else /* __U_BOOT__ */ + /* + * Environment variable set with setenv* have to be + * expanded. + * So, we first search if the variable exists in + * environment, if this is not the case, we default to + * local value. + */ + val = env_get(var); + if (!val) + val = get_local_var_value(var); +#endif /* __U_BOOT__ */ } } @@ -7375,7 +7410,11 @@ static NOINLINE int expand_vars_to_list(o_string *output, int n, char *arg) case '*': case '@': { int i; +#ifndef __U_BOOT__ if (!G.global_argv[1]) +#else /* __U_BOOT__ */ + if (!G.global_argv || !G.global_argv[1]) +#endif /* __U_BOOT__ */ break; i = 1; cant_be_null |= first_ch; /* do it for "$@" _now_, when we know it's not empty */ @@ -9976,7 +10015,30 @@ static NOINLINE int run_pipe(struct pipe *pi) #endif /* !__U_BOOT__ */ command = &pi->cmds[cmd_no]; cmd_no++; - if (command->argv) { + +#ifdef __U_BOOT__ + /* Replace argv and argc by expanded if it exists. */ + if (argv_expanded) { + /* + * We need to save a pointer to argv, we will restore it + * later, so it will be freed when pipe is freed. + */ + argv = command->argv; + + /* + * After expansion, there can be more or less argument, so we need to + * update argc, for example: + * - More arguments: + * foo='bar quuz' + * echo $foo + * - Less arguments: + * echo $foo (if foo was never set) + */ + command->argc = list_size(argv_expanded); + command->argv = argv_expanded; + } +#endif /* __U_BOOT__ */ + if (command->argv) { debug_printf_exec(": pipe member '%s' '%s'...\n", command->argv[0], command->argv[1]); } else { @@ -10091,6 +10153,25 @@ static NOINLINE int run_pipe(struct pipe *pi) rcode = cmd_process(G.do_repeat ? CMD_FLAG_REPEAT : 0, command->argc, command->argv, &(G.flag_repeat), NULL); + + if (argv_expanded) { + /* + * expand_strvec_to_strvec() allocates memory to expand + * argv, we need to free it. + */ + free(argv_expanded); + + /* + * We also restore command->argv to its original value + * so no memory leak happens. + */ + command->argv = argv; + + /* + * NOTE argc exists only in U-Boot, so argv freeing does + * not rely on it as this code exists in BusyBox. + */ + } #endif /* __U_BOOT__ */ } -- 2.39.5