hush: fix mishandling of a'b'c=fff as assignments. They are not.

function                                             old     new   delta
parse_stream                                        1920    2004     +84
done_word                                            715     752     +37
parse_and_run_stream                                 328     333      +5
builtin_exec                                          25      29      +4
pseudo_exec_argv                                     138     139      +1
run_list                                            2006    1999      -7
is_assignment                                        215     134     -81
------------------------------------------------------------------------------
(add/remove: 0/0 grow/shrink: 5/2 up/down: 131/-88)            Total: 43 bytes
This commit is contained in:
Denis Vlasenko 2008-08-04 00:46:07 +00:00
parent c8bec9a085
commit 2b576b8e76
5 changed files with 129 additions and 60 deletions

View File

@ -318,10 +318,12 @@ struct redir_struct {
struct child_prog {
pid_t pid; /* 0 if exited */
int assignment_cnt; /* how many argv[i] are assignments? */
smallint is_stopped; /* is the program currently running? */
smallint subshell; /* flag, non-zero if group must be forked */
struct pipe *group; /* if non-NULL, this "prog" is {} group,
* subshell, or a compound statement */
char **argv; /* program name and arguments */
struct pipe *group; /* if non-NULL, first in group or subshell */
struct redir_struct *redirects; /* I/O redirections */
};
/* argv vector may contain variable references (^Cvar^C, ^C0^C etc)
@ -377,6 +379,7 @@ enum {
MAYBE_ASSIGNMENT = 0,
DEFINITELY_ASSIGNMENT = 1,
NOT_ASSIGNMENT = 2,
WORD_IS_KEYWORD = 3, /* not assigment, but next word may be: "if v=xyz cmd;" */
};
/* Used for initialization: o_string foo = NULL_O_STRING; */
#define NULL_O_STRING { NULL }
@ -430,7 +433,6 @@ struct globals {
pid_t last_bg_pid;
#if ENABLE_HUSH_JOB
int run_list_level;
// pid_t saved_task_pgrp;
pid_t saved_tty_pgrp;
int last_jobid;
struct pipe *job_list;
@ -524,10 +526,12 @@ static int free_pipe(struct pipe *pi, int indent);
static int setup_redirects(struct child_prog *prog, int squirrel[]);
static int run_list(struct pipe *pi);
#if BB_MMU
#define pseudo_exec_argv(ptrs2free, argv, argv_expanded) pseudo_exec_argv(argv, argv_expanded)
#define pseudo_exec(ptrs2free, child, argv_expanded) pseudo_exec(child, argv_expanded)
#define pseudo_exec_argv(ptrs2free, argv, assignment_cnt, argv_expanded) \
pseudo_exec_argv(argv, assignment_cnt, argv_expanded)
#define pseudo_exec(ptrs2free, child, argv_expanded) \
pseudo_exec(child, argv_expanded)
#endif
static void pseudo_exec_argv(char **ptrs2free, char **argv, char **argv_expanded) NORETURN;
static void pseudo_exec_argv(char **ptrs2free, char **argv, int assignment_cnt, char **argv_expanded) NORETURN;
static void pseudo_exec(char **ptrs2free, struct child_prog *child, char **argv_expanded) NORETURN;
static int run_pipe(struct pipe *pi);
/* data structure manipulation: */
@ -1390,13 +1394,13 @@ static void restore_redirects(int squirrel[])
* XXX no exit() here. If you don't exec, use _exit instead.
* The at_exit handlers apparently confuse the calling process,
* in particular stdin handling. Not sure why? -- because of vfork! (vda) */
static void pseudo_exec_argv(char **ptrs2free, char **argv, char **argv_expanded)
static void pseudo_exec_argv(char **ptrs2free, char **argv, int assignment_cnt, char **argv_expanded)
{
int i, rcode;
char *p;
const struct built_in_command *x;
for (i = 0; is_assignment(argv[i]); i++) {
for (i = 0; i < assignment_cnt; i++) {
debug_printf_exec("pid %d environment modification: %s\n",
getpid(), argv[i]);
p = expand_string_to_string(argv[i]);
@ -1466,7 +1470,7 @@ static void pseudo_exec_argv(char **ptrs2free, char **argv, char **argv_expanded
static void pseudo_exec(char **ptrs2free, struct child_prog *child, char **argv_expanded)
{
if (child->argv)
pseudo_exec_argv(ptrs2free, child->argv, argv_expanded);
pseudo_exec_argv(ptrs2free, child->argv, child->assignment_cnt, argv_expanded);
if (child->group) {
#if !BB_MMU
@ -1713,8 +1717,6 @@ static int checkjobs_and_fg_shell(struct pipe* fg_pipe)
p = getpgid(0); /* pgid of our process */
debug_printf_jobs("fg'ing ourself: getpgid(0)=%d\n", (int)p);
tcsetpgrp(G.interactive_fd, p);
// if (tcsetpgrp(G.interactive_fd, p) && errno != ENOTTY)
// bb_perror_msg("tcsetpgrp-4a");
return rcode;
}
#endif
@ -1780,8 +1782,7 @@ static int run_pipe(struct pipe *pi)
argv = child->argv;
if (single_and_fg && argv != NULL) {
for (i = 0; is_assignment(argv[i]); i++)
continue;
i = child->assignment_cnt;
if (i != 0 && argv[i] == NULL) {
/* assignments, but no command: set local environment */
for (i = 0; argv[i] != NULL; i++) {
@ -1793,7 +1794,7 @@ static int run_pipe(struct pipe *pi)
}
/* Expand assignments into one string each */
for (i = 0; is_assignment(argv[i]); i++) {
for (i = 0; i < child->assignment_cnt; i++) {
p = expand_string_to_string(argv[i]);
putenv(p);
//FIXME: do we leak p?!
@ -1991,7 +1992,7 @@ static void debug_print_tree(struct pipe *pi, int lvl)
struct child_prog *child = &pi->progs[prn];
char **argv = child->argv;
fprintf(stderr, "%*s prog %d", lvl*2, "", prn);
fprintf(stderr, "%*s prog %d assignment_cnt:%d", lvl*2, "", prn, child->assignment_cnt);
if (child->group) {
fprintf(stderr, " group %s: (argv=%p)\n",
(child->subshell ? "()" : "{}"),
@ -2165,30 +2166,31 @@ static int run_list(struct pipe *pi)
vals = (char**)encoded_dollar_at_argv;
if (pi->next->res_word == RES_IN) {
/* if no variable values after "in" we skip "for" */
if (!pi->next->progs->argv)
if (!pi->next->progs[0].argv)
break;
vals = pi->next->progs->argv;
vals = pi->next->progs[0].argv;
} /* else: "for var; do..." -> assume "$@" list */
/* create list of variable values */
debug_print_strings("for_list made from", vals);
for_list = expand_strvec_to_strvec(vals);
for_lcur = for_list;
debug_print_strings("for_list", for_list);
for_varname = pi->progs->argv[0];
pi->progs->argv[0] = NULL;
for_varname = pi->progs[0].argv[0];
pi->progs[0].argv[0] = NULL;
}
free(pi->progs->argv[0]);
free(pi->progs[0].argv[0]);
if (!*for_lcur) {
/* "for" loop is over, clean up */
free(for_list);
for_list = NULL;
for_lcur = NULL;
pi->progs->argv[0] = for_varname;
pi->progs[0].argv[0] = for_varname;
break;
}
/* insert next value from for_lcur */
//TODO: does it need escaping?
pi->progs->argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++);
pi->progs[0].argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++);
pi->progs[0].assignment_cnt = 1;
}
if (rword == RES_IN) /* "for v IN list;..." - "in" has no cmds anyway */
continue;
@ -2902,11 +2904,12 @@ static void initialize_context(struct p_context *ctx)
* case, function, and select are obnoxious, save those for later.
*/
#if HAS_KEYWORDS
static int reserved_word(const o_string *word, struct p_context *ctx)
static int reserved_word(o_string *word, struct p_context *ctx)
{
struct reserved_combo {
char literal[7];
char literal[6];
unsigned char res;
unsigned char assignment_flag;
int flag;
};
enum {
@ -2939,29 +2942,29 @@ static int reserved_word(const o_string *word, struct p_context *ctx)
*/
static const struct reserved_combo reserved_list[] = {
#if ENABLE_HUSH_IF
{ "!", RES_NONE, 0 },
{ "if", RES_IF, FLAG_THEN | FLAG_START },
{ "then", RES_THEN, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
{ "elif", RES_ELIF, FLAG_THEN },
{ "else", RES_ELSE, FLAG_FI },
{ "fi", RES_FI, FLAG_END },
{ "!", RES_NONE, NOT_ASSIGNMENT , 0 },
{ "if", RES_IF, WORD_IS_KEYWORD, FLAG_THEN | FLAG_START },
{ "then", RES_THEN, WORD_IS_KEYWORD, FLAG_ELIF | FLAG_ELSE | FLAG_FI },
{ "elif", RES_ELIF, WORD_IS_KEYWORD, FLAG_THEN },
{ "else", RES_ELSE, WORD_IS_KEYWORD, FLAG_FI },
{ "fi", RES_FI, NOT_ASSIGNMENT , FLAG_END },
#endif
#if ENABLE_HUSH_LOOPS
{ "for", RES_FOR, FLAG_IN | FLAG_DO | FLAG_START },
{ "while", RES_WHILE, FLAG_DO | FLAG_START },
{ "until", RES_UNTIL, FLAG_DO | FLAG_START },
{ "in", RES_IN, FLAG_DO },
{ "do", RES_DO, FLAG_DONE },
{ "done", RES_DONE, FLAG_END },
{ "for", RES_FOR, NOT_ASSIGNMENT , FLAG_IN | FLAG_DO | FLAG_START },
{ "while", RES_WHILE, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
{ "until", RES_UNTIL, WORD_IS_KEYWORD, FLAG_DO | FLAG_START },
{ "in", RES_IN, NOT_ASSIGNMENT , FLAG_DO },
{ "do", RES_DO, WORD_IS_KEYWORD, FLAG_DONE },
{ "done", RES_DONE, NOT_ASSIGNMENT , FLAG_END },
#endif
#if ENABLE_HUSH_CASE
{ "case", RES_CASE, FLAG_MATCH | FLAG_START },
{ "esac", RES_ESAC, FLAG_END },
{ "case", RES_CASE, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_START },
{ "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END },
#endif
};
#if ENABLE_HUSH_CASE
static const struct reserved_combo reserved_match = {
"" /* "match" */, RES_MATCH, FLAG_MATCH | FLAG_ESAC
"", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC
};
#endif
const struct reserved_combo *r;
@ -3008,6 +3011,7 @@ static int reserved_word(const o_string *word, struct p_context *ctx)
*ctx = *old; /* physical copy */
free(old);
}
word->o_assignment = r->assignment_flag;
return 1;
}
return 0;
@ -3021,17 +3025,22 @@ static int done_word(o_string *word, struct p_context *ctx)
struct child_prog *child = ctx->child;
debug_printf_parse("done_word entered: '%s' %p\n", word->data, child);
/* If this word wasn't an assignment, next ones definitely
* can't be assignments. Even if they look like ones. */
if (word->o_assignment != DEFINITELY_ASSIGNMENT) {
word->o_assignment = NOT_ASSIGNMENT;
} else {
word->o_assignment = MAYBE_ASSIGNMENT;
}
if (word->length == 0 && word->nonnull == 0) {
debug_printf_parse("done_word return 0: true null, ignored\n");
return 0;
}
/* If this word wasn't an assignment, next ones definitely
* can't be assignments. Even if they look like ones. */
if (word->o_assignment != DEFINITELY_ASSIGNMENT
&& word->o_assignment != WORD_IS_KEYWORD
) {
word->o_assignment = NOT_ASSIGNMENT;
} else {
if (word->o_assignment == DEFINITELY_ASSIGNMENT)
child->assignment_cnt++;
word->o_assignment = MAYBE_ASSIGNMENT;
}
if (ctx->pending_redirect) {
/* We do not glob in e.g. >*.tmp case. bash seems to glob here
* only if run as "bash", not "sh" */
@ -3066,7 +3075,6 @@ static int done_word(o_string *word, struct p_context *ctx)
debug_printf_parse(": checking '%s' for reserved-ness\n", word->data);
if (reserved_word(word, ctx)) {
o_reset(word);
word->o_assignment = NOT_ASSIGNMENT;
debug_printf_parse("done_word return %d\n", (ctx->ctx_res_w == RES_SNTX));
return (ctx->ctx_res_w == RES_SNTX);
}
@ -3343,11 +3351,6 @@ static int process_command_subs(o_string *dest,
o_addchr(dest, '\n');
eol_cnt--;
}
// /* Even unquoted `echo '\'` results in two backslashes
// * (which are converted into one by globbing later) */
// if (!dest->o_quote && ch == '\\') {
// o_addchr(dest, ch);
// }
o_addQchr(dest, ch);
}
@ -3367,6 +3370,9 @@ static int process_command_subs(o_string *dest,
static int parse_group(o_string *dest, struct p_context *ctx,
struct in_str *input, int ch)
{
/* NB: parse_group may create and use its own o_string,
* without any code changes. It just so happens that code is smaller
* if we (ab)use caller's one. */
int rcode;
const char *endch = NULL;
struct p_context sub;
@ -3624,7 +3630,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
* A single-quote triggers a bypass of the main loop until its mate is
* found. When recursing, quote state is passed in via dest->o_quote. */
debug_printf_parse("parse_stream entered, end_trigger='%s'\n", end_trigger);
debug_printf_parse("parse_stream entered, end_trigger='%s' dest->o_assignment:%d\n", end_trigger, dest->o_assignment);
while (1) {
m = CHAR_IFS;
@ -3647,7 +3653,8 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
return 1;
}
o_addQchr(dest, ch);
if (dest->o_assignment == MAYBE_ASSIGNMENT
if ((dest->o_assignment == MAYBE_ASSIGNMENT
|| dest->o_assignment == WORD_IS_KEYWORD)
&& ch == '='
&& is_assignment(dest->data)
) {
@ -3676,6 +3683,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
}
#endif
done_pipe(ctx, PIPE_SEQ);
dest->o_assignment = MAYBE_ASSIGNMENT;
}
}
if (end_trigger) {
@ -3686,6 +3694,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
done_word(dest, ctx);
//err chk?
done_pipe(ctx, PIPE_SEQ);
dest->o_assignment = MAYBE_ASSIGNMENT;
}
if (!HAS_KEYWORDS
IF_HAS_KEYWORDS(|| (ctx->ctx_res_w == RES_NONE && ctx->old_flag == 0))
@ -3841,6 +3850,10 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
}
}
#endif
new_cmd:
/* We just finished a cmd. New one may start
* with an assignment */
dest->o_assignment = MAYBE_ASSIGNMENT;
break;
case '&':
done_word(dest, ctx);
@ -3850,14 +3863,14 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
} else {
done_pipe(ctx, PIPE_BG);
}
break;
goto new_cmd;
case '|':
done_word(dest, ctx);
#if ENABLE_HUSH_CASE
if (ctx->ctx_res_w == RES_MATCH)
break; /* we are in case's "word | word)" */
#endif
if (next == '|') {
if (next == '|') { /* || */
i_getch(input);
done_pipe(ctx, PIPE_OR);
} else {
@ -3866,7 +3879,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
* "echo foo 2| cat" yields "foo 2". */
done_command(ctx);
}
break;
goto new_cmd;
case '(':
#if ENABLE_HUSH_CASE
/* "case... in [(]word)..." - skip '(' */
@ -3881,7 +3894,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
debug_printf_parse("parse_stream return 1: parse_group returned non-0\n");
return 1;
}
break;
goto new_cmd;
case ')':
#if ENABLE_HUSH_CASE
if (ctx->ctx_res_w == RES_MATCH)
@ -3947,6 +3960,7 @@ static int parse_and_run_stream(struct in_str *inp, int parse_flag)
/* We will stop & execute after each ';' or '\n'.
* Example: "sleep 9999; echo TEST" + ctrl-C:
* TEST should be printed */
temp.o_assignment = MAYBE_ASSIGNMENT;
rcode = parse_stream(&temp, &ctx, inp, ";\n");
#if HAS_KEYWORDS
if (rcode != 1 && ctx.old_flag != 0) {
@ -4006,9 +4020,7 @@ static void setup_job_control(void)
{
pid_t shell_pgrp;
// G.saved_task_pgrp =
shell_pgrp = getpgrp();
// debug_printf_jobs("saved_task_pgrp=%d\n", G.saved_task_pgrp);
close_on_exec_on(G.interactive_fd);
/* If we were ran as 'hush &',
@ -4302,7 +4314,7 @@ static int builtin_exec(char **argv)
char **ptrs2free = alloc_ptrs(argv);
#endif
// FIXME: if exec fails, bash does NOT exit! We do...
pseudo_exec_argv(ptrs2free, argv + 1, NULL);
pseudo_exec_argv(ptrs2free, argv + 1, 0, NULL);
/* never returns */
}
}

View File

@ -0,0 +1,9 @@
if1:0
while1:0
until1:0
if2:0
while2:0
until2:0
if3:0
while3:0
until3:0

View File

@ -0,0 +1,42 @@
# Assignments after some keywords should still work
if a=1 true; then a=1 true; elif a=1 true; then a=1 true; else a=1 true; fi
echo if1:$?
while a=1 true; do a=1 true; break; done
echo while1:$?
until a=1 false; do a=1 true; break; done
echo until1:$?
if a=1 true
then a=1 true
elif a=1 true
then a=1 true
else a=1 true
fi
echo if2:$?
while a=1 true
do a=1 true
break
done
echo while2:$?
until a=1 false
do a=1 true
break
done
echo until2:$?
if
a=1 true; then
a=1 true; elif
a=1 true; then
a=1 true; else
a=1 true; fi
echo if3:$?
while
a=1 true; do
a=1 true; break; done
echo while3:$?
until
a=1 false; do
a=1 true; break; done
echo until3:$?

View File

@ -0,0 +1,2 @@
hush: can't exec 'a=b': No such file or directory
1

View File

@ -0,0 +1,4 @@
# This must not be interpreted as an assignment
a''=b true
echo $?
# (buglet: $? should be 127. it is currently 1)