From 9aa7d6fdc5554480b9cb4fc740ce3f1d2b734555 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Sat, 4 Apr 2009 22:47:50 +0000 Subject: hush: preparatory patch for NOMMU-safe { list } handling. function old new delta o_addblock - 58 +58 o_addstr_with_NUL - 27 +27 builtin_exit 47 49 +2 run_list 2020 2018 -2 o_addstrauto 27 - -27 parse_stream 1508 1461 -47 o_addstr 58 - -58 ------------------------------------------------------------------------------ (add/remove: 2/2 grow/shrink: 1/2 up/down: 87/-134) Total: -47 bytes --- shell/hush.c | 291 ++++++++++++++++++++++++++++++++++++++++------------------- 1 file changed, 200 insertions(+), 91 deletions(-) (limited to 'shell') diff --git a/shell/hush.c b/shell/hush.c index c38420240..ac3480578 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -73,10 +73,18 @@ #if ENABLE_HUSH_CASE #include #endif - #include "math.h" -#define HUSH_VER_STR "0.92" +#ifdef WANT_TO_TEST_NOMMU +# undef BB_MMU +# undef USE_FOR_NOMMU +# undef USE_FOR_MMU +# define BB_MMU 0 +# define USE_FOR_NOMMU(...) __VA_ARGS__ +# define USE_FOR_MMU(...) +#endif + +#define HUSH_VER_STR "0.93" #if defined SINGLE_APPLET_MAIN /* STANDALONE does not make sense, and won't compile */ @@ -298,6 +306,45 @@ typedef enum reserved_style { RES_SNTX } reserved_style; +typedef struct o_string { + char *data; + int length; /* position where data is appended */ + int maxlen; + /* Protect newly added chars against globbing + * (by prepending \ to *, ?, [, \) */ + smallint o_escape; + smallint o_glob; + smallint nonnull; + smallint has_empty_slot; + smallint o_assignment; /* 0:maybe, 1:yes, 2:no */ +} o_string; +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 } + +/* I can almost use ordinary FILE*. Is open_memstream() universally + * available? Where is it documented? */ +typedef struct in_str { + const char *p; + /* eof_flag=1: last char in ->p is really an EOF */ + char eof_flag; /* meaningless if ->p == NULL */ + char peek_buf[2]; +#if ENABLE_HUSH_INTERACTIVE + smallint promptme; + smallint promptmode; /* 0: PS1, 1: PS2 */ +#endif + FILE *file; + int (*get) (struct in_str *); + int (*peek) (struct in_str *); +} in_str; +#define i_getch(input) ((input)->get(input)) +#define i_peek(input) ((input)->peek(input)) + struct redir_struct { struct redir_struct *next; char *rd_filename; /* filename */ @@ -311,8 +358,11 @@ struct command { int assignment_cnt; /* how many argv[i] are assignments? */ smallint is_stopped; /* is the command currently running? */ smallint grp_type; /* GRP_xxx */ - struct pipe *group; /* if non-NULL, this "prog" is {} group, - * subshell, or a compound statement */ + struct pipe *group; /* if non-NULL, this "command" is { list }, + * ( list ), or a compound statement */ +#if !BB_MMU + char *group_as_string; +#endif char **argv; /* command name and arguments */ struct redir_struct *redirects; /* I/O redirections */ }; @@ -354,6 +404,9 @@ struct parse_context { struct command *command; /* last redirect in command->redirects list */ struct redir_struct *pending_redirect; +#if !BB_MMU + o_string as_string; +#endif #if HAS_KEYWORDS smallint ctx_res_w; smallint ctx_inverted; /* "! cmd | cmd" */ @@ -389,45 +442,6 @@ struct variable { smallint flg_read_only; }; -typedef struct o_string { - char *data; - int length; /* position where data is appended */ - int maxlen; - /* Protect newly added chars against globbing - * (by prepending \ to *, ?, [, \) */ - smallint o_escape; - smallint o_glob; - smallint nonnull; - smallint has_empty_slot; - smallint o_assignment; /* 0:maybe, 1:yes, 2:no */ -} o_string; -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 } - -/* I can almost use ordinary FILE*. Is open_memstream() universally - * available? Where is it documented? */ -typedef struct in_str { - const char *p; - /* eof_flag=1: last char in ->p is really an EOF */ - char eof_flag; /* meaningless if ->p == NULL */ - char peek_buf[2]; -#if ENABLE_HUSH_INTERACTIVE - smallint promptme; - smallint promptmode; /* 0: PS1, 1: PS2 */ -#endif - FILE *file; - int (*get) (struct in_str *); - int (*peek) (struct in_str *); -} in_str; -#define i_getch(input) ((input)->get(input)) -#define i_peek(input) ((input)->peek(input)) - enum { BC_BREAK = 1, BC_CONTINUE = 2, @@ -1359,6 +1373,11 @@ static void o_free(o_string *o) memset(o, 0, sizeof(*o)); } +static ALWAYS_INLINE void o_free_unsafe(o_string *o) +{ + free(o->data); +} + static void o_grow_by(o_string *o, int len) { if (o->length + len > o->maxlen) { @@ -1376,7 +1395,7 @@ static void o_addchr(o_string *o, int ch) o->data[o->length] = '\0'; } -static void o_addstr(o_string *o, const char *str, int len) +static void o_addblock(o_string *o, const char *str, int len) { o_grow_by(o, len); memcpy(&o->data[o->length], str, len); @@ -1384,12 +1403,19 @@ static void o_addstr(o_string *o, const char *str, int len) o->data[o->length] = '\0'; } -static void o_addstrauto(o_string *o, const char *str) +#if !BB_MMU +static void o_addstr(o_string *o, const char *str) +{ + o_addblock(o, str, strlen(str)); +} +#endif + +static void o_addstr_with_NUL(o_string *o, const char *str) { - o_addstr(o, str, strlen(str) + 1); + o_addblock(o, str, strlen(str) + 1); } -static void o_addstr_duplicate_backslash(o_string *o, const char *str, int len) +static void o_addblock_duplicate_backslash(o_string *o, const char *str, int len) { while (len) { o_addchr(o, *str); @@ -1438,7 +1464,7 @@ static void o_addQchr(o_string *o, int ch) static void o_addQstr(o_string *o, const char *str, int len) { if (!o->o_escape) { - o_addstr(o, str, len); + o_addblock(o, str, len); return; } while (len) { @@ -1447,7 +1473,7 @@ static void o_addQstr(o_string *o, const char *str, int len) int ordinary_cnt = strcspn(str, "*?[\\"); if (ordinary_cnt > len) /* paranoia */ ordinary_cnt = len; - o_addstr(o, str, ordinary_cnt); + o_addblock(o, str, ordinary_cnt); if (ordinary_cnt == len) return; str += ordinary_cnt; @@ -1582,7 +1608,7 @@ static int o_glob(o_string *o, int n) char **argv = globdata.gl_pathv; o->length = pattern - o->data; /* "forget" pattern */ while (1) { - o_addstrauto(o, *argv); + o_addstr_with_NUL(o, *argv); n = o_save_ptr_helper(o, n); argv++; if (!*argv) @@ -1635,7 +1661,14 @@ static char **o_finalize_list(o_string *o, int n) static int process_command_subs(o_string *dest, const char *s); #endif static char *expand_string_to_string(const char *str); -static int parse_stream_dquoted(o_string *dest, struct in_str *input, int dquote_end); +#if BB_MMU +#define parse_stream_dquoted(ctx, dest, input, dquote_end) \ + parse_stream_dquoted(dest, input, dquote_end) +#endif +static int parse_stream_dquoted(struct parse_context *ctx, + o_string *dest, + struct in_str *input, + int dquote_end); /* expand_strvec_to_strvec() takes a list of strings, expands * all variable references within and returns a pointer to @@ -1657,7 +1690,7 @@ static int expand_on_ifs(o_string *output, int n, const char *str) if (output->o_escape || !output->o_glob) o_addQstr(output, str, word_len); else /* protect backslashes against globbing up :) */ - o_addstr_duplicate_backslash(output, str, word_len); + o_addblock_duplicate_backslash(output, str, word_len); str += word_len; } if (!*str) /* EOL - do not finalize word */ @@ -1701,7 +1734,7 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask) #if ENABLE_SH_MATH_SUPPORT char arith_buf[sizeof(arith_t)*3 + 2]; #endif - o_addstr(output, arg, p - arg); + o_addblock(output, arg, p - arg); debug_print_list("expand_vars_to_list[1]", output, n); arg = ++p; p = strchr(p, SPECIAL_VAR_SYMBOL); @@ -1825,7 +1858,7 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask) o_string dest = NULL_O_STRING; setup_string_in_str(&input, arg); - parse_stream_dquoted(&dest, &input, EOF); + parse_stream_dquoted(NULL, &dest, &input, EOF); //bb_error_msg("'%s' -> '%s'", arg, dest.data); exp_str = expand_string_to_string(dest.data); //bb_error_msg("'%s' -> '%s'", dest.data, exp_str); @@ -1958,7 +1991,7 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask) debug_print_list("expand_vars_to_list[a]", output, n); /* this part is literal, and it was already pre-quoted * if needed (much earlier), do not use o_addQstr here! */ - o_addstrauto(output, arg); + o_addstr_with_NUL(output, arg); debug_print_list("expand_vars_to_list[b]", output, n); } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */ && !(ored_ch & 0x80) /* and all vars were not quoted. */ @@ -2148,6 +2181,10 @@ static void free_pipe(struct pipe *pi, int indent) debug_printf_clean("%s end group\n", indenter(indent)); command->group = NULL; } +#if !BB_MMU + free(command->group_as_string); + command->group_as_string = NULL; +#endif for (r = command->redirects; r; r = rnext) { debug_printf_clean("%s redirect %d%s", indenter(indent), r->fd, redir_table[r->rd_type].descrip); if (r->dup == -1) { @@ -2215,9 +2252,7 @@ static void pseudo_exec_argv(nommu_save_t *nommu_save, char **argv, int assignment_cnt, char **argv_expanded) { - int rcode; char **new_env; - const struct built_in_command *x; /* Case when we are here: ... | var=val | ... */ if (!argv[assignment_cnt]) @@ -2251,12 +2286,17 @@ static void pseudo_exec_argv(nommu_save_t *nommu_save, * easier to waste a few CPU cycles than it is to figure out * if this is one of those cases. */ - for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) { - if (strcmp(argv[0], x->cmd) == 0) { - debug_printf_exec("running builtin '%s'\n", argv[0]); - rcode = x->function(argv); - fflush(NULL); - _exit(rcode); + { + int rcode; + const struct built_in_command *x; + for (x = bltins; x != &bltins[ARRAY_SIZE(bltins)]; x++) { + if (strcmp(argv[0], x->cmd) == 0) { + debug_printf_exec("running builtin '%s'\n", + argv[0]); + rcode = x->function(argv); + fflush(NULL); + _exit(rcode); + } } } #endif @@ -2320,8 +2360,8 @@ static void pseudo_exec(nommu_save_t *nommu_save, * since this process is about to exit */ _exit(rcode); #else -//TODO: re-exec "hush -c command->group_as_a_string" - bb_error_msg_and_die("nested lists are not supported on NOMMU"); + bb_error_msg_and_die("NOMMU TODO: re-exec '%s'", + command->group_as_string); #endif } @@ -3587,6 +3627,13 @@ static int reserved_word(o_string *word, struct parse_context *ctx) old = ctx->stack; old->command->group = ctx->list_head; old->command->grp_type = GRP_NORMAL; +#if !BB_MMU + o_addstr(&old->as_string, ctx->as_string.data); + o_free_unsafe(&ctx->as_string); + old->command->group_as_string = xstrdup(old->as_string.data); + debug_printf_parse("pop, remembering as:'%s'\n", + old->command->group_as_string); +#endif *ctx = *old; /* physical copy */ free(old); } @@ -3739,7 +3786,13 @@ static int redirect_opt_num(o_string *o) return num; } -static struct pipe *parse_stream(struct in_str *input, int end_trigger); +#if BB_MMU +#define parse_stream(pstring, input, end_trigger) \ + parse_stream(input, end_trigger) +#endif +static struct pipe *parse_stream(char **pstring, + struct in_str *input, + int end_trigger); static void parse_and_run_string(const char *s); #if ENABLE_HUSH_TICK @@ -3864,15 +3917,33 @@ static int parse_group(o_string *dest, struct parse_context *ctx, endch = ')'; command->grp_type = GRP_SUBSHELL; } - pipe_list = parse_stream(input, endch); - /* empty ()/{} or parse error? */ - if (!pipe_list || pipe_list == ERR_PTR) { - syntax(NULL); - debug_printf_parse("parse_group return 1: " - "parse_stream returned %p\n", pipe_list); - return 1; + { +#if !BB_MMU + char *as_string = NULL; +#endif + pipe_list = parse_stream(&as_string, input, endch); +#if !BB_MMU + if (as_string) + o_addstr(&ctx->as_string, as_string); +#endif + /* empty ()/{} or parse error? */ + if (!pipe_list || pipe_list == ERR_PTR) { +#if !BB_MMU + free(as_string); +#endif + syntax(NULL); + debug_printf_parse("parse_group return 1: " + "parse_stream returned %p\n", pipe_list); + return 1; + } + command->group = pipe_list; +#if !BB_MMU + as_string[strlen(as_string) - 1] = '\0'; /* plink ')' or '}' */ + command->group_as_string = as_string; + debug_printf_parse("end of group, remembering as:'%s'\n", + command->group_as_string); +#endif } - command->group = pipe_list; debug_printf_parse("parse_group return 0\n"); return 0; /* command remains "open", available for possible redirects */ @@ -4151,14 +4222,24 @@ static int handle_dollar(o_string *dest, struct in_str *input) return 0; } -static int parse_stream_dquoted(o_string *dest, - struct in_str *input, int dquote_end) +#if BB_MMU +#define parse_stream_dquoted(ctx, dest, input, dquote_end) \ + parse_stream_dquoted(dest, input, dquote_end) +#endif +static int parse_stream_dquoted(struct parse_context *ctx, + o_string *dest, + struct in_str *input, + int dquote_end) { int ch; int next; again: ch = i_getch(input); +#if !BB_MMU + if (ctx && ch != EOF) + o_addchr(&ctx->as_string, ch); +#endif if (ch == dquote_end) { /* may be only '"' or EOF */ dest->nonnull = 1; if (dest->o_assignment == NOT_ASSIGNMENT) @@ -4237,15 +4318,13 @@ static int parse_stream_dquoted(o_string *dest, * reset parsing machinery and start parsing anew, * or return ERR_PTR. */ -static struct pipe *parse_stream(struct in_str *input, int end_trigger) +static struct pipe *parse_stream(char **pstring, + struct in_str *input, + int end_trigger) { struct parse_context ctx; o_string dest = NULL_O_STRING; - int redir_fd; - int next; int is_in_dquote; - int ch; - redir_type redir_style; /* Double-quote state is handled in the state variable is_in_dquote. * A single-quote triggers a bypass of the main loop until its mate is @@ -4268,15 +4347,18 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) while (1) { const char *is_ifs; const char *is_special; + int ch; + int next; + int redir_fd; + redir_type redir_style; if (is_in_dquote) { - if (parse_stream_dquoted(&dest, input, '"')) { + if (parse_stream_dquoted(&ctx, &dest, input, '"')) { goto parse_error; } /* We reached closing '"' */ is_in_dquote = 0; } - next = '\0'; ch = i_getch(input); debug_printf_parse(": ch=%c (%d) escape=%d\n", ch, ch, dest.o_escape); @@ -4287,8 +4369,9 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) } o_free(&dest); done_pipe(&ctx, PIPE_SEQ); - /* If we got nothing... */ pi = ctx.list_head; + /* If we got nothing... */ +// TODO: test script consisting of just "&" if (pi->num_cmds == 0 IF_HAS_KEYWORDS( && pi->res_word == RES_NONE) ) { @@ -4296,12 +4379,18 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) pi = NULL; } debug_printf_parse("parse_stream return %p\n", pi); +#if !BB_MMU + debug_printf_parse("as_string '%s'\n", ctx.as_string.data); + if (pstring) + *pstring = ctx.as_string.data; + else + o_free_unsafe(&ctx.as_string); +#endif return pi; } - if (ch != '\n') { - next = i_peek(input); - } - +#if !BB_MMU + o_addchr(&ctx.as_string, ch); +#endif is_ifs = strchr(G.ifs, ch); is_special = strchr("<>;&|(){}#'" /* special outside of "str" */ "\\$\"" USE_HUSH_TICK("`") /* always special */ @@ -4356,6 +4445,13 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) "end_trigger char found\n", ctx.list_head); o_free(&dest); +#if !BB_MMU + debug_printf_parse("as_string '%s'\n", ctx.as_string.data); + if (pstring) + *pstring = ctx.as_string.data; + else + o_free_unsafe(&ctx.as_string); +#endif return ctx.list_head; } } @@ -4368,6 +4464,11 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) dest.o_assignment = NOT_ASSIGNMENT; } + next = '\0'; + if (ch != '\n') { + next = i_peek(input); + } + switch (ch) { case '#': if (dest.length == 0) { @@ -4601,6 +4702,9 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) debug_print_tree(pctx->list_head, 0); free_pipe_list(pctx->list_head, 0); debug_printf_clean("freed list %p\n", pctx->list_head); +#if !BB_MMU + o_free_unsafe(&pctx->as_string); +#endif IF_HAS_KEYWORDS(p2 = pctx->stack;) if (pctx != &ctx) { free(pctx); @@ -4612,8 +4716,13 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) /* If we are not in top-level parse, we return, * our caller will propagate error. */ - if (end_trigger != ';') + if (end_trigger != ';') { +#if !BB_MMU + if (pstring) + *pstring = NULL; +#endif return ERR_PTR; + } /* Discard cached input, force prompt */ input->p = NULL; USE_HUSH_INTERACTIVE(input->promptme = 1;) @@ -4621,7 +4730,7 @@ static struct pipe *parse_stream(struct in_str *input, int end_trigger) } } -/* Execiting from string: eval, sh -c '...' +/* Executing from string: eval, sh -c '...' * or from file: /etc/profile, . file, sh