This commit adds the following hush busybox upstream commits: 93ae7464e6e4 ("hush: restore SIGHUP handling, this time explain why we do what we do") 1fdb33bd07e5 ("hush: restore tty pgrp on SIGHUP") 6101b6d3eaa0 ("hush: remove special handling of SIGHUP") 93e0898c663a ("shell: fix SIGWINCH and SIGCHLD (in hush) interrupting line input, closes 15256") 969e00816835 ("hush: code shrink") 27be0e8cfeb6 ("shell: fix compile failures in some configs") 7d1c7d833785 ("ash,hush: use HOME for tab completion and prompts") 21afddefd258 ("hush: fix "error: invalid preprocessing directive ##"") e53c7dbafc78 ("hush: fix set -n to act immediately, not just after run_list() ") 574b9c446da1 ("hush: fix var_LINENO3.tests failure") 49bcf9f40cff ("hush: speed up ${x//*/|} too") 53b2fdcdba4c ("*: add NOINLINEs where code noticeably shrinks") 7c3e96d4b3d4 ("shell: use more compact SHELL_ASH / HUSH config defines. no code changes") 62f1eed1e191 ("hush: in a comment, document what -i might be doing") aaf3d5ba74c5 ("shell: tweak --help") db5546ca1018 ("libbb: code shrink: introduce and use [_]exit_SUCCESS()") 931c55f9e2b4 ("libbb: invert the meaning of SETUP_ENV_NO_CHDIR -> SETUP_ENV_CHDIR") 12566e7f9b5e ("ash,hush: fix handling of SIGINT while waiting for interactive input") 987be932ed3c ("*: slap on a few ALIGN_PTR where appropriate")
Signed-off-by: Francis Laniel francis.laniel@amarulasolutions.com --- common/cli_hush_2021.c | 2 +- common/cli_hush_upstream.c | 224 +++++++++++++++++++++++++++---------- 2 files changed, 164 insertions(+), 62 deletions(-)
diff --git a/common/cli_hush_2021.c b/common/cli_hush_2021.c index 0a207d147b..4c46176cb2 100644 --- a/common/cli_hush_2021.c +++ b/common/cli_hush_2021.c @@ -26,7 +26,7 @@ /* * BusyBox Version: UPDATE THIS WHEN PULLING NEW UPSTREAM REVISION! */ -#define BB_VER "1.34.0.git37460f5daff9" +#define BB_VER "1.35.0.git7d1c7d833785"
/* * Define hush features by the names used upstream. diff --git a/common/cli_hush_upstream.c b/common/cli_hush_upstream.c index 23392939e1..93796e87c5 100644 --- a/common/cli_hush_upstream.c +++ b/common/cli_hush_upstream.c @@ -339,7 +339,7 @@ * therefore we don't show them either. */ //usage:#define hush_trivial_usage -//usage: "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE [ARGS] | -s [ARGS]]" +//usage: "[-enxl] [-c 'SCRIPT' [ARG0 ARGS] | FILE ARGS | -s ARGS]" //usage:#define hush_full_usage "\n\n" //usage: "Unix shell interpreter"
@@ -374,7 +374,7 @@ # define F_DUPFD_CLOEXEC F_DUPFD #endif
-#if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !(ENABLE_ASH || ENABLE_SH_IS_ASH || ENABLE_BASH_IS_ASH) +#if ENABLE_FEATURE_SH_EMBEDDED_SCRIPTS && !ENABLE_SHELL_ASH # include "embedded_scripts.h" #else # define NUM_SCRIPTS 0 @@ -574,7 +574,7 @@ enum { #define NULL_O_STRING { NULL }
#ifndef debug_printf_parse -static const char *const assignment_flag[] = { +static const char *const assignment_flag[] ALIGN_PTR = { "MAYBE_ASSIGNMENT", "DEFINITELY_ASSIGNMENT", "NOT_ASSIGNMENT", @@ -958,6 +958,7 @@ struct globals { #if ENABLE_HUSH_INTERACTIVE smallint promptmode; /* 0: PS1, 1: PS2 */ #endif + /* set by signal handler if SIGINT is received _and_ its trap is not set */ smallint flag_SIGINT; #ifndef __U_BOOT__ #if ENABLE_HUSH_LOOPS @@ -1918,7 +1919,13 @@ static void restore_G_args(save_arg_t *sv, char **argv) * SIGQUIT: ignore * SIGTERM (interactive): ignore * SIGHUP (interactive): - * send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit + * Send SIGCONT to stopped jobs, send SIGHUP to all jobs and exit. + * Kernel would do this for us ("orphaned process group" handling + * according to POSIX) if we are a session leader and thus our death + * frees the controlling tty, but to be bash-compatible, we also do it + * for every interactive shell's death by SIGHUP. + * (Also, we need to restore tty pgrp, otherwise e.g. Midnight Commander + * backgrounds when hush started from it gets killed by SIGHUP). * SIGTTIN, SIGTTOU, SIGTSTP (if job control is on): ignore * Note that ^Z is handled not by trapping SIGTSTP, but by seeing * that all pipe members are stopped. Try this in bash: @@ -2034,6 +2041,14 @@ enum { static void record_pending_signo(int sig) { sigaddset(&G.pending_set, sig); +#if ENABLE_FEATURE_EDITING + if (sig != SIGCHLD + || (G_traps && G_traps[SIGCHLD] && G_traps[SIGCHLD][0]) + /* ^^^ if SIGCHLD, interrupt line reading only if it has a trap */ + ) { + bb_got_signal = sig; /* for read_line_input: "we got a signal" */ + } +#endif #if ENABLE_HUSH_FAST if (sig == SIGCHLD) { G.count_SIGCHLD++; @@ -2265,20 +2280,27 @@ static int check_and_run_traps(void) break; #if ENABLE_HUSH_JOB case SIGHUP: { -//TODO: why are we doing this? ash and dash don't do this, -//they have no handler for SIGHUP at all, -//they rely on kernel to send SIGHUP+SIGCONT to orphaned process groups - struct pipe *job; - debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig); - /* bash is observed to signal whole process groups, - * not individual processes */ - for (job = G.job_list; job; job = job->next) { - if (job->pgrp <= 0) - continue; - debug_printf_exec("HUPing pgrp %d\n", job->pgrp); - if (kill(- job->pgrp, SIGHUP) == 0) - kill(- job->pgrp, SIGCONT); + /* if (G_interactive_fd) - no need to check, the handler + * is only installed if we *are* interactive */ + { + /* bash compat: "Before exiting, an interactive + * shell resends the SIGHUP to all jobs, running + * or stopped. Stopped jobs are sent SIGCONT + * to ensure that they receive the SIGHUP." + */ + struct pipe *job; + debug_printf_exec("%s: sig:%d default SIGHUP handler\n", __func__, sig); + /* bash is observed to signal whole process groups, + * not individual processes */ + for (job = G.job_list; job; job = job->next) { + if (job->pgrp <= 0) + continue; + debug_printf_exec("HUPing pgrp %d\n", job->pgrp); + if (kill(- job->pgrp, SIGHUP) == 0) + kill(- job->pgrp, SIGCONT); + } } + /* this restores tty pgrp, then kills us with SIGHUP */ sigexit(SIGHUP); } #endif @@ -2581,10 +2603,15 @@ int set_local_var_2021(char *str, int flags) }
#ifndef __U_BOOT__ +static int set_local_var0(char *str) +{ + return set_local_var(str, 0); +} + static void FAST_FUNC set_local_var_from_halves(const char *name, const char *val) { char *var = xasprintf("%s=%s", name, val); - set_local_var(var, /*flag:*/ 0); + set_local_var0(var); }
/* Used at startup and after each cd */ @@ -2788,30 +2815,54 @@ static void get_user_input(struct in_str *i) for (;;) { reinit_unicode_for_hush(); G.flag_SIGINT = 0; - /* buglet: SIGINT will not make new prompt to appear _at once_, - * only after <Enter>. (^C works immediately) */ - r = read_line_input(G.line_input_state, prompt_str, + + bb_got_signal = 0; + if (!sigisemptyset(&G.pending_set)) { + /* Whoops, already got a signal, do not call read_line_input */ + bb_got_signal = r = -1; + } else { + /* For shell, LI_INTERRUPTIBLE is set: + * read_line_input will abort on either + * getting EINTR in poll() and bb_got_signal became != 0, + * or if it sees bb_got_signal != 0 + * (IOW: if signal arrives before poll() is reached). + * Interactive testcases: + * (while kill -INT $$; do sleep 1; done) & + * #^^^ prints ^C, prints prompt, repeats + * trap 'echo I' int; (while kill -INT $$; do sleep 1; done) & + * #^^^ prints ^C, prints "I", prints prompt, repeats + * trap 'echo T' term; (while kill $$; do sleep 1; done) & + * #^^^ prints "T", prints prompt, repeats + * #(bash 5.0.17 exits after first "T", looks like a bug) + */ + r = read_line_input(G.line_input_state, prompt_str, G.user_input_buf, CONFIG_FEATURE_EDITING_MAX_LEN-1 - ); - /* read_line_input intercepts ^C, "convert" it to SIGINT */ - if (r == 0) { - raise(SIGINT); + ); + /* read_line_input intercepts ^C, "convert" it to SIGINT */ + if (r == 0) + raise(SIGINT); + } + /* bash prints ^C (before running a trap, if any) + * both on keyboard ^C and on real SIGINT (non-kbd generated). + */ + if (sigismember(&G.pending_set, SIGINT)) { + write(STDOUT_FILENO, "^C\n", 3); + G.last_exitcode = 128 | SIGINT; } check_and_run_traps(); - if (r != 0 && !G.flag_SIGINT) + if (r == 0) /* keyboard ^C? */ + continue; /* go back, read another input line */ + if (r > 0) /* normal input? (no ^C, no ^D, no signals) */ break; - /* ^C or SIGINT: repeat */ - /* bash prints ^C even on real SIGINT (non-kbd generated) */ - write(STDOUT_FILENO, "^C\n", 3); - G.last_exitcode = 128 | SIGINT; - } - if (r < 0) { - /* EOF/error detected */ - /* ^D on interactive input goes to next line before exiting: */ - write(STDOUT_FILENO, "\n", 1); - i->p = NULL; - i->peek_buf[0] = r = EOF; - return r; + if (!bb_got_signal) { + /* r < 0: ^D/EOF/error detected (but not signal) */ + /* ^D on interactive input goes to next line before exiting: */ + write(STDOUT_FILENO, "\n", 1); + i->p = NULL; + i->peek_buf[0] = r = EOF; + return r; + } + /* it was a signal: go back, read another input line */ } i->p = G.user_input_buf; return (unsigned char)*i->p++; @@ -2991,6 +3042,12 @@ static int i_getch(struct in_str *i) if (ch != '\0') { i->p++; i->last_char = ch; +#if ENABLE_HUSH_LINENO_VAR + if (ch == '\n') { + G.parse_lineno++; + debug_printf_parse("G.parse_lineno++ = %u\n", G.parse_lineno); + } +#endif return ch; } return EOF; @@ -3638,7 +3695,7 @@ static int glob_brace(char *pattern, o_string *o, int n) * NEXT points past the terminator of the first element, and REST * points past the final }. We will accumulate result names from * recursive runs for each brace alternative in the buffer using - * GLOB_APPEND. */ + * GLOB_APPEND. */
p = begin + 1; while (1) { @@ -3954,7 +4011,7 @@ static void free_pipe_list(struct pipe *pi) #ifndef debug_print_tree static void debug_print_tree(struct pipe *pi, int lvl) { - static const char *const PIPE[] = { + static const char *const PIPE[] ALIGN_PTR = { [PIPE_SEQ] = "SEQ", [PIPE_AND] = "AND", [PIPE_OR ] = "OR" , @@ -3989,7 +4046,7 @@ static void debug_print_tree(struct pipe *pi, int lvl) [RES_XXXX ] = "XXXX" , [RES_SNTX ] = "SNTX" , }; - static const char *const CMDTYPE[] = { + static const char *const CMDTYPE[] ALIGN_PTR = { "{}", "()", "[noglob]", @@ -5354,7 +5411,7 @@ static int parse_dollar_squote(o_string *as_string, o_string *dest, struct in_st # undef as_string } #else -# #define parse_dollar_squote(as_string, dest, input) 0 +# define parse_dollar_squote(as_string, dest, input) 0 #endif /* BASH_DOLLAR_SQUOTE */ #endif /* !__U_BOOT__ */
@@ -6721,7 +6778,7 @@ static char *encode_then_expand_vararg(const char *str, int handle_squotes, int
/* Expanding ARG in ${var+ARG}, ${var-ARG} */ -static int encode_then_append_var_plusminus(o_string *output, int n, +static NOINLINE int encode_then_append_var_plusminus(o_string *output, int n, char *str, int dquoted) { struct in_str input; @@ -6886,16 +6943,21 @@ static arith_t expand_and_evaluate_arith(const char *arg, const char **errmsg_p) /* ${var/[/]pattern[/repl]} helpers */ static char *strstr_pattern(char *val, const char *pattern, int *size) { - int sz = strcspn(pattern, "*?[\"); - if (pattern[sz] == '\0') { + int first_escaped = (pattern[0] == '\' && pattern[1]); + /* "first_escaped" trick allows to treat e.g. "*no_glob_chars" + * as literal too (as it is semi-common, and easy to accomodate + * by just using str + 1). + */ + int sz = strcspn(pattern + first_escaped * 2, "*?[\"); + if ((pattern + first_escaped * 2)[sz] == '\0') { /* Optimization for trivial patterns. * Testcase for very slow replace (performs about 22k replaces): * x=:::::::::::::::::::::: * x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;x=$x$x;echo ${#x} * echo "${x//:/|}" */ - *size = sz; - return strstr(val, pattern); + *size = sz + first_escaped; + return strstr(val, pattern + first_escaped); }
while (1) { @@ -7371,7 +7433,7 @@ static NOINLINE int expand_one_var(o_string *output, int n, val = NULL; } else { char *new_var = xasprintf("%s=%s", var, val); - set_local_var(new_var, /*flag:*/ 0); + set_local_var0(new_var); } } } @@ -8026,7 +8088,11 @@ static int parse_and_run_string(const char *s) #endif /* __U_BOOT__ */ { struct in_str input; +#ifndef __U_BOOT__ + IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) +#else /* __U_BOOT__ */ //IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) +#endif /* __U_BOOT__ */
setup_string_in_str(&input, s); #ifndef __U_BOOT__ @@ -8034,7 +8100,11 @@ static int parse_and_run_string(const char *s) #else /* __U_BOOT__ */ return parse_and_run_stream(&input, '\0'); #endif /* __U_BOOT__ */ - //IF_HUSH_LINENO_VAR(G.parse_lineno = sv;) +#ifndef __U_BOOT__ + IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) +#else /* __U_BOOT__ */ + //IF_HUSH_LINENO_VAR(unsigned sv = G.parse_lineno;) +#endif /* __U_BOOT__ */ }
#ifdef __U_BOOT__ @@ -8142,7 +8212,7 @@ static int generate_stream_from_string(const char *s, pid_t *pid_p) if (is_prefixed_with(s, "trap") && skip_whitespace(s + 4)[0] == '\0' ) { - static const char *const argv[] = { NULL, NULL }; + static const char *const argv[] ALIGN_PTR = { NULL, NULL }; builtin_trap((char**)argv); fflush_all(); /* important */ _exit(0); @@ -8671,7 +8741,7 @@ static const struct built_in_command *find_builtin(const char *name) return find_builtin_helper(name, bltins2, &bltins2[ARRAY_SIZE(bltins2)]); }
-#if ENABLE_HUSH_JOB && EDITING_HAS_get_exe_name +#if ENABLE_HUSH_JOB && ENABLE_FEATURE_TAB_COMPLETION static const char * FAST_FUNC get_builtin_name(int i) { if (/*i >= 0 && */ i < ARRAY_SIZE(bltins1)) { @@ -9107,7 +9177,7 @@ static NOINLINE void pseudo_exec_argv(nommu_save_t *nommu_save, * expand_assignments(): think about ... | var=`sleep 1` | ... */ free_strings(new_env); - _exit(EXIT_SUCCESS); + _exit_SUCCESS(); }
sv_shadowed = G.shadowed_vars_pp; @@ -9288,7 +9358,7 @@ static void pseudo_exec(nommu_save_t *nommu_save,
/* Case when we are here: ... | >file */ debug_printf_exec("pseudo_exec'ed null command\n"); - _exit(EXIT_SUCCESS); + _exit_SUCCESS(); }
#if ENABLE_HUSH_JOB @@ -9895,7 +9965,7 @@ static NOINLINE int run_pipe(struct pipe *pi) #endif debug_printf_env("set shell var:'%s'->'%s'\n", *argv, p); #ifndef __U_BOOT__ - if (set_local_var(p, /*flag:*/ 0)) { + if (set_local_var0(p)) { #else /* __U_BOOT__ */ if (set_local_var_2021(p, /*flag:*/ 0)) { #endif @@ -10421,7 +10491,7 @@ static int run_list(struct pipe *pi) static const char encoded_dollar_at[] ALIGN1 = { SPECIAL_VAR_SYMBOL, '@' | 0x80, SPECIAL_VAR_SYMBOL, '\0' }; /* encoded representation of "$@" */ - static const char *const encoded_dollar_at_argv[] = { + static const char *const encoded_dollar_at_argv[] ALIGN_PTR = { encoded_dollar_at, NULL }; /* argv list with one element: "$@" */ char **vals; @@ -10452,7 +10522,7 @@ static int run_list(struct pipe *pi) /* Insert next value from for_lcur */ /* note: *for_lcur already has quotes removed, $var expanded, etc */ #ifndef __U_BOOT__ - set_local_var(xasprintf("%s=%s", pi->cmds[0].argv[0], *for_lcur++), /*flag:*/ 0); + set_local_var_from_halves(pi->cmds[0].argv[0], *for_lcur++); #else /* __U_BOOT__ */ /* We cannot use xasprintf, so we emulate it. */ char *full_var; @@ -10548,8 +10618,11 @@ static int run_list(struct pipe *pi) G.flag_break_continue = 0; #endif #endif /* !__U_BOOT__ */ +#ifndef __U_BOOT__ + rcode = r = G.o_opt[OPT_O_NOEXEC] ? 0 : run_pipe(pi); + /* NB: rcode is a smalluint, r is int */ +#else /* __U_BOOT__ */ rcode = r = run_pipe(pi); /* NB: rcode is a smalluint, r is int */ -#ifdef __U_BOOT__ if (r <= EXIT_RET_CODE) { int previous_rcode = G.last_exitcode; /* @@ -10839,7 +10912,10 @@ static int set_mode(int state, char mode, const char *o_opt) int idx; switch (mode) { case 'n': - G.o_opt[OPT_O_NOEXEC] = state; + /* set -n has no effect in interactive shell */ + /* Try: while set -n; do echo $-; done */ + if (!G_interactive_fd) + G.o_opt[OPT_O_NOEXEC] = state; break; case 'x': IF_HUSH_MODE_X(G_x_mode = state;) @@ -10912,7 +10988,7 @@ int hush_main(int argc, char **argv)
cached_getpid = getpid(); /* for tcsetpgrp() during init */ G.root_pid = cached_getpid; /* for $PID (NOMMU can override via -$HEXPID:HEXPPID:...) */ - G.root_ppid = getppid(); /* for $PPID (NOMMU can override) */ + G.root_ppid = getppid(); /* for $PPID (NOMMU can override) */
/* Deal with HUSH_VERSION */ debug_printf_env("unsetenv '%s'\n", "HUSH_VERSION"); @@ -11043,6 +11119,29 @@ int hush_main(int argc, char **argv) /* Well, we cannot just declare interactiveness, * we have to have some stuff (ctty, etc) */ /* G_interactive_fd++; */ +//There are a few cases where bash -i -c 'SCRIPT' +//has visible effect (differs from bash -c 'SCRIPT'): +//it ignores TERM: +// bash -i -c 'kill $$; echo ALIVE' +// ALIVE +//it resets SIG_IGNed HUP to SIG_DFL: +// trap '' hup; bash -i -c 'kill -hup $$; echo ALIVE' +// Hangup [the message is not printed by bash, it's the shell which started it] +//is talkative about jobs and exiting: +// bash -i -c 'sleep 1 & exit' +// [1] 16170 +// exit +//includes $ENV file (only if run as "sh"): +// echo last >/tmp/ENV; ENV=/tmp/ENV sh -i -c 'echo HERE' +// last: cannot open /var/log/wtmp: No such file or directory +// HERE +//(under "bash", it's the opposite: it runs $BASH_ENV file only *without* -i). +// +//ash -i -c 'sleep 3; sleep 3', on ^C, drops into a prompt instead of exiting +//(this may be a bug, bash does not do this). +//(ash -i -c 'sleep 3' won't show this, the last command gets auto-"exec"ed) +// +//None of the above feel like useful features people would rely on. break; case 's': G.opt_s = 1; @@ -11307,9 +11406,12 @@ int hush_main(int argc, char **argv)
# if ENABLE_FEATURE_EDITING G.line_input_state = new_line_input_t(FOR_SHELL); -# if EDITING_HAS_get_exe_name +# if ENABLE_FEATURE_TAB_COMPLETION G.line_input_state->get_exe_name = get_builtin_name; # endif +# if EDITING_HAS_sh_get_var + G.line_input_state->sh_get_var = get_local_var_value; +# endif # endif # if ENABLE_HUSH_SAVEHISTORY && MAX_HISTORY > 0 { @@ -12422,7 +12524,7 @@ static int FAST_FUNC builtin_fg_bg(char **argv) /* TODO: bash prints a string representation * of job being foregrounded (like "sleep 1 | cat") */ if (argv[0][0] == 'f' && G_saved_tty_pgrp) { - /* Put the job into the foreground. */ + /* Put the job into the foreground. */ tcsetpgrp(G_interactive_fd, pi->pgrp); }