diff options
| -rw-r--r-- | shell/hush.c | 367 | ||||
| -rw-r--r-- | shell/hush_test/hush-bugs/quote3.right | 8 | ||||
| -rw-r--r-- | shell/hush_test/hush-bugs/quote3.tests | 12 | ||||
| -rw-r--r-- | shell/hush_test/hush-vars/var_subst_in_for.right | 40 | ||||
| -rw-r--r-- | shell/hush_test/hush-vars/var_subst_in_for.tests | 40 |
5 files changed, 404 insertions, 63 deletions
diff --git a/shell/hush.c b/shell/hush.c index dfb8191..803970b 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -85,13 +85,14 @@ /* If you comment out one of these below, it will be #defined later * to perform debug printfs to stderr: */ -#define debug_printf(...) do {} while (0) +#define debug_printf(...) do {} while (0) /* Finer-grained debug switches */ -#define debug_printf_parse(...) do {} while (0) -#define debug_print_tree(a, b) do {} while (0) -#define debug_printf_exec(...) do {} while (0) -#define debug_printf_jobs(...) do {} while (0) -#define debug_printf_clean(...) do {} while (0) +#define debug_printf_parse(...) do {} while (0) +#define debug_print_tree(a, b) do {} while (0) +#define debug_printf_exec(...) do {} while (0) +#define debug_printf_jobs(...) do {} while (0) +#define debug_printf_expand(...) do {} while (0) +#define debug_printf_clean(...) do {} while (0) #ifndef debug_printf #define debug_printf(...) fprintf(stderr, __VA_ARGS__) @@ -110,6 +111,11 @@ #define DEBUG_SHELL_JOBS 1 #endif +#ifndef debug_printf_expand +#define debug_printf_expand(...) fprintf(stderr, __VA_ARGS__) +#define DEBUG_EXPAND 1 +#endif + #ifndef debug_printf_clean /* broken, of course, but OK for testing */ static const char *indenter(int i) @@ -229,6 +235,12 @@ struct child_prog { int sp; /* number of SPECIAL_VAR_SYMBOL */ int type; }; +// sp counting seems to be broken... +/* argv vector may contain variable references (^Cvar^C, ^C0^C etc) + * and on execution these are substituted with their values. + * Substitution can make _several_ words out of one argv[n]! + * Example: argv[0]=='.^C*^C.' here: echo .$*. + */ struct pipe { struct pipe *next; @@ -430,7 +442,7 @@ static void delete_finished_bg_job(struct pipe *pi); int checkjobs_and_fg_shell(struct pipe* fg_pipe); /* never called */ #endif /* local variable support */ -static char **make_list_in(char **inp, char *name); +static char **do_variable_expansion(char **argv); static char *insert_var_value(char *inp); static const char *get_local_var(const char *var); static int set_local_var(const char *s, int flg_export); @@ -1265,10 +1277,8 @@ static void restore_redirects(int squirrel[]) for (i = 0; i < 3; i++) { fd = squirrel[i]; if (fd != -1) { - /* No error checking. I sure wouldn't know what - * to do with an error if I found one! */ - dup2(fd, i); - close(fd); + /* We simply die on error */ + xmove_fd(fd, i); } } } @@ -1916,9 +1926,9 @@ static int run_list_real(struct pipe *pi) enum { level = 0 }; #endif - char *save_name = NULL; - char **list = NULL; - char **save_list = NULL; + char *for_varname = NULL; + char **for_lcur = NULL; + char **for_list = NULL; struct pipe *rpipe; int flag_rep = 0; int save_num_progs; @@ -2018,30 +2028,29 @@ static int run_list_real(struct pipe *pi) if (rmode == RES_ELIF && !if_code) break; if (rmode == RES_FOR && pi->num_progs) { - if (!list) { + if (!for_lcur) { /* if no variable values after "in" we skip "for" */ if (!pi->next->progs->argv) continue; /* create list of variable values */ - list = make_list_in(pi->next->progs->argv, - pi->progs->argv[0]); - save_list = list; - save_name = pi->progs->argv[0]; + for_list = do_variable_expansion(pi->next->progs->argv); + for_lcur = for_list; + for_varname = pi->progs->argv[0]; pi->progs->argv[0] = NULL; flag_rep = 1; } - if (!*list) { - free(pi->progs->argv[0]); - free(save_list); - list = NULL; + free(pi->progs->argv[0]); + if (!*for_lcur) { + free(for_list); + for_lcur = NULL; flag_rep = 0; - pi->progs->argv[0] = save_name; + pi->progs->argv[0] = for_varname; pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0]; continue; } - /* insert new value from list for variable */ - free(pi->progs->argv[0]); - pi->progs->argv[0] = *list++; + /* insert next value from for_lcur */ + //vda: does it need escaping? + pi->progs->argv[0] = xasprintf("%s=%s", for_varname, *for_lcur++); pi->progs->glob_result.gl_pathv[0] = pi->progs->argv[0]; } if (rmode == RES_IN) @@ -2288,50 +2297,267 @@ static int xglob(o_string *dest, int flags, glob_t *pglob) return gr; } -static char **make_list_in(char **inp, char *name) + +/* do_variable_expansion() takes a list of strings, expands + * all variable references within and returns a pointer to + * a list of expanded strings, possibly with larger number + * of strings. (Think VAR="a b"; echo $VAR). + * This new list is allocated as a single malloc block. + * NULL-terminated list of char* pointers is at the beginning of it, + * followed by strings themself. + * Caller can deallocate entire list by single free(list). */ + +/* Helpers first: + * count_XXX estimates, how large block do we need. It's okay + * to over-estimate sizes a bit, if it makes code simpler */ +static int count_ifs(const char *str) { - int len, i; -#if 0 - int name_len = strlen(name); -#endif - int n; - char **list; - char *p1, *p2, *p3; + int cnt = 0; + debug_printf_expand("count_ifs('%s') ifs='%s'", str, ifs); + while (1) { + str += strcspn(str, ifs); + if (!*str) break; + str++; // str += strspn(str, ifs); ? + cnt++; // cnt += strspn(str, ifs); ? + } + debug_printf_expand(" return %d\n", cnt); + return cnt; +} - /* create list of variable values */ - list = xmalloc(sizeof(*list)); - n = 0; - for (i = 0; inp[i]; i++) { - p3 = insert_var_value(inp[i]); - p1 = p3; - while (*p1) { - if (*p1 == ' ') { - p1++; - continue; +static void count_var_expansion_space(int *countp, int *lenp, char *arg) +{ + char first_ch; + int i; + int len = *lenp; + int count = *countp; + const char *val; + char *p; + + while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) { + len += p - arg; + arg = ++p; + p = strchr(p, SPECIAL_VAR_SYMBOL); + first_ch = arg[0]; + + switch (first_ch & 0x7f) { + /* high bit in 1st_ch indicates that var is double-quoted */ + case '$': /* pid */ + case '!': /* bg pid */ + case '?': /* exitcode */ + case '#': /* argc */ + len += sizeof(int)*3 + 1; /* enough for int */ + break; + case '*': + case '@': + for (i = 1; i < global_argc; i++) { + len += strlen(global_argv[i]) + 1; + count++; + if (!(first_ch & 0x80)) + count += count_ifs(global_argv[i]); + } + break; + default: + *p = '\0'; + arg[0] = first_ch & 0x7f; + val = lookup_param(arg); + arg[0] = first_ch; + *p = SPECIAL_VAR_SYMBOL; + + if (val) { + len += strlen(val) + 1; + if (!(first_ch & 0x80)) + count += count_ifs(val); } - p2 = strchrnul(p1, ' '); - len = p2 - p1; - /* we use n + 2 in realloc for list, because we add - * new element and then we will add NULL element */ - list = xrealloc(list, sizeof(*list) * (n + 2)); - list[n] = xasprintf("%s=%.*s", name, len, p1); -#if 0 /* faster, but more code */ - list[n] = xmalloc(2 + name_len + len); - strcpy(list[n], name); - list[n][name_len] = '='; - strncat(&(list[n][name_len + 1]), p1, len); - list[n][name_len + len + 1] = '\0'; -#endif - n++; - p1 = p2; } - if (p3 != inp[i]) - free(p3); + arg = ++p; } + + len += strlen(arg) + 1; + count++; + *lenp = len; + *countp = count; +} + +/* Store given string, finalizing the word and starting new one whenever + * we encounter ifs char(s). This is used for expanding variable values. + * End-of-string does NOT finalize word, because cases like echo -$VAR- */ +static int expand_on_ifs(char **list, int n, char **posp, const char *str) +{ + char *pos = *posp; + while (1) { + int word_len = strcspn(str, ifs); + if (word_len) { + memcpy(pos, str, word_len); /* store non-ifs chars */ + pos += word_len; + str += word_len; + if (!*str) /* EOL - do not finalize word */ + break; + *pos++ = '\0'; + if (n) debug_printf_expand("expand_on_ifs finalized list[%d]=%p '%s' " + "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], + strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); + list[n++] = pos; + } + if (!*str) break; /* EOL, not ifs char */ + str += strspn(str, ifs); /* skip ifs chars */ + } + *posp = pos; + return n; +} + +/* Expand all variable references in given string, adding words to list[] + * at n, n+1,... positions. Return updated n (so that list[n] is next one + * to be filled). This routine is extremely tricky: has to deal with + * variables/parameters with whitespace, $* and $@, and constructs like + * 'echo -$*-'. If you play here, you must run testsuite afterwards! */ +/* NB: support for double-quoted expansion is not used yet (we never set + * magic bit 0x80 elsewhere...) */ +/* NB: another bug is that we cannot detect empty strings yet: + * "" or $empty"" expands to zero words, has to expand to empty word */ +static int expand_vars_to_list(char **list, int n, char **posp, char *arg) +{ + char first_ch, ored_ch; + const char *val; + char *p; + char *pos = *posp; + + ored_ch = 0; + + if (n) debug_printf_expand("expand_vars_to_list finalized list[%d]=%p '%s' " + "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], + strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); + list[n++] = pos; + + while ((p = strchr(arg, SPECIAL_VAR_SYMBOL))) { + memcpy(pos, arg, p - arg); + pos += (p - arg); + arg = ++p; + p = strchr(p, SPECIAL_VAR_SYMBOL); + + first_ch = arg[0]; + ored_ch |= first_ch; + val = NULL; + switch (first_ch & 0x7f) { + /* Highest bit in first_ch indicates that var is double-quoted */ + case '$': /* pid */ + /* FIXME: (echo $$) should still print pid of main shell */ + val = utoa(getpid()); + break; + case '!': /* bg pid */ + val = last_bg_pid ? utoa(last_bg_pid) : (char*)""; + break; + case '?': /* exitcode */ + val = utoa(last_return_code); + break; + case '#': /* argc */ + val = utoa(global_argc ? global_argc-1 : 0); + break; + case '*': + case '@': + if (!(first_ch & 0x80)) { /* unquoted $* or $@ */ + int i = 1; + while (i < global_argc) { + n = expand_on_ifs(list, n, &pos, global_argv[i]); + debug_printf_expand("expand_vars_to_list: argv %d (last %d)\n", i, global_argc-1); + if (global_argv[i++][0] && i < global_argc) { + /* this argv[] is not empty and not last: + * put terminating NUL, start new word */ + *pos++ = '\0'; + if (n) debug_printf_expand("expand_vars_to_list 2 finalized list[%d]=%p '%s' " + "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], + strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); + list[n++] = pos; + } + } + } else if (first_ch == ('@'|0x80)) { /* quoted $@ */ + /* TODO */ + } else { /* quoted $* */ + /* TODO */ + } + break; + default: + *p = '\0'; + arg[0] = first_ch & 0x7f; + val = lookup_param(arg); + arg[0] = first_ch; + *p = SPECIAL_VAR_SYMBOL; + if (!(first_ch & 0x80)) { /* unquoted var */ + if (val) { + n = expand_on_ifs(list, n, &pos, val); + val = NULL; + } + } + } + if (val) { + strcpy(pos, val); + pos += strlen(val); + } + arg = ++p; + } + debug_printf_expand("expand_vars_to_list adding tail '%s' at %p\n", arg, pos); + strcpy(pos, arg); + pos += strlen(arg) + 1; + if (pos == list[n-1] + 1) { /* expansion is empty */ + if (!(ored_ch & 0x80)) { /* all vars were not quoted... */ + debug_printf_expand("expand_vars_to_list list[%d] empty, going back\n", n); + pos--; + n--; + } + } + + *posp = pos; + return n; +} + +static char **do_variable_expansion(char **argv) +{ + int n; + int count = 1; + int len = 0; + char *pos, **v, **list; + + v = argv; + if (!*v) debug_printf_expand("count_var_expansion_space: " + "argv[0]=NULL count=%d len=%d alloc_space=%d\n", + count, len, sizeof(char*) * count + len); + while (*v) { + count_var_expansion_space(&count, &len, *v); + debug_printf_expand("count_var_expansion_space: " + "'%s' count=%d len=%d alloc_space=%d\n", + *v, count, len, sizeof(char*) * count + len); + v++; + } + len += sizeof(char*) * count; /* total to alloc */ + list = xmalloc(len); + pos = (char*)(list + count); + debug_printf_expand("list=%p, list[0] should be %p\n", list, pos); + n = 0; + v = argv; + while (*v) + n = expand_vars_to_list(list, n, &pos, *v++); + + if(n) debug_printf_expand("finalized list[%d]=%p '%s' " + "strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1], + strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos); list[n] = NULL; + +#ifdef DEBUG_EXPAND + { + int m = 0; + while (m <= n) { + debug_printf_expand("list[%d]=%p '%s'\n", m, list[m], list[m]); + m++; + } + debug_printf_expand("used_space=%d\n", pos - (char*)list); + } +#endif + /* To be removed / made conditional later. */ + if (pos - (char*)list > len) + bb_error_msg_and_die("BUG in varexp"); return list; } + static char *insert_var_value(char *inp) { int res_str_len = 0; @@ -2404,6 +2630,21 @@ static char *insert_var_value(char *inp) return (res_str == NULL) ? inp : res_str; } + + + + + + + + + + + + + + + /* This is used to get/check local shell variables */ static const char *get_local_var(const char *s) { @@ -2986,7 +3227,7 @@ static const char *lookup_param(const char *src) } /* Make new string for parser */ -static char* make_string(char ** inp) +static char* make_string(char **inp) { char *p; char *str = NULL; diff --git a/shell/hush_test/hush-bugs/quote3.right b/shell/hush_test/hush-bugs/quote3.right new file mode 100644 index 0000000..11443f5 --- /dev/null +++ b/shell/hush_test/hush-bugs/quote3.right @@ -0,0 +1,8 @@ +Testing: in $empty"" +.. +Testing: in "$*" +.abc d e. +Testing: in "$@" +.abc. +.d e. +Finished diff --git a/shell/hush_test/hush-bugs/quote3.tests b/shell/hush_test/hush-bugs/quote3.tests new file mode 100644 index 0000000..c52e040 --- /dev/null +++ b/shell/hush_test/hush-bugs/quote3.tests @@ -0,0 +1,12 @@ +if test $# = 0; then + exec "$THIS_SH" quote3.tests abc "d e" +fi + +echo 'Testing: in $empty""' +empty='' +for a in $empty""; do echo ".$a."; done +echo 'Testing: in "$*"' +for a in "$*"; do echo ".$a."; done +echo 'Testing: in "$@"' +for a in "$@"; do echo ".$a."; done +echo Finished diff --git a/shell/hush_test/hush-vars/var_subst_in_for.right b/shell/hush_test/hush-vars/var_subst_in_for.right new file mode 100644 index 0000000..c8aca1c --- /dev/null +++ b/shell/hush_test/hush-vars/var_subst_in_for.right @@ -0,0 +1,40 @@ +Testing: in x y z +.x. +.y. +.z. +Testing: in u $empty v +.u. +.v. +Testing: in u " $empty" v +.u. +. . +.v. +Testing: in u $empty $empty$a v +.u. +.a. +.v. +Testing: in $a_b +.a. +.b. +Testing: in $* +.abc. +.d. +.e. +Testing: in $@ +.abc. +.d. +.e. +Testing: in -$*- +.-abc. +.d. +.e-. +Testing: in -$@- +.-abc. +.d. +.e-. +Testing: in $a_b -$a_b- +.a. +.b. +.-a. +.b-. +Finished diff --git a/shell/hush_test/hush-vars/var_subst_in_for.tests b/shell/hush_test/hush-vars/var_subst_in_for.tests new file mode 100644 index 0000000..4d1c112 --- /dev/null +++ b/shell/hush_test/hush-vars/var_subst_in_for.tests @@ -0,0 +1,40 @@ +if test $# = 0; then + exec "$THIS_SH" var_subst_in_for.tests abc "d e" +fi + +echo 'Testing: in x y z' +for a in x y z; do echo ".$a."; done + +echo 'Testing: in u $empty v' +empty='' +for a in u $empty v; do echo ".$a."; done + +echo 'Testing: in u " $empty" v' +empty='' +for a in u " $empty" v; do echo ".$a."; done + +echo 'Testing: in u $empty $empty$a v' +a='a' +for a in u $empty $empty$a v; do echo ".$a."; done + +echo 'Testing: in $a_b' +a_b='a b' +for a in $a_b; do echo ".$a."; done + +echo 'Testing: in $*' +for a in $*; do echo ".$a."; done + +echo 'Testing: in $@' +for a in $@; do echo ".$a."; done + +echo 'Testing: in -$*-' +for a in -$*-; do echo ".$a."; done + +echo 'Testing: in -$@-' +for a in -$@-; do echo ".$a."; done + +echo 'Testing: in $a_b -$a_b-' +a_b='a b' +for a in $a_b -$a_b-; do echo ".$a."; done + +echo Finished |