From 5ec6132c9884f1f6ccbcc8277cb73220462a2133 Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Tue, 24 Jun 2008 00:50:07 +0000 Subject: [PATCH] hush: ifdef out parts which are not needed if neither loops nor ifs are supported. Code savings: function old new delta parse_stream 1758 1757 -1 checkjobs 335 318 -17 done_pipe 74 52 -22 expand_variables 1437 1407 -30 run_list 1232 1189 -43 parse_and_run_stream 328 267 -61 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 0/6 up/down: 0/-174) Total: -174 bytes --- shell/hush.c | 105 +++++++++++++++++++++++++++++---------------------- 1 file changed, 59 insertions(+), 46 deletions(-) diff --git a/shell/hush.c b/shell/hush.c index b59f67942..ace0cdafc 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -150,9 +150,6 @@ #define debug_printf_subst(...) fprintf(stderr, __VA_ARGS__) #endif -/* Keep unconditionally on for now */ -#define ENABLE_HUSH_DEBUG 1 - #ifndef debug_printf_clean /* broken, of course, but OK for testing */ static const char *indenter(int i) @@ -176,7 +173,6 @@ static void debug_print_strings(const char *prefix, char **vv) #define debug_print_strings(prefix, vv) ((void)0) #endif - /* * Leak hunting. Use hush_leaktool.sh for post-processing. */ @@ -216,6 +212,20 @@ void xxfree(void *ptr) #endif +/* Keep unconditionally on for now */ +#define HUSH_DEBUG 1 +/* Do we support ANY keywords? */ +#if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS +#define HAS_KEYWORDS 1 +#define IF_HAS_KEYWORDS(...) __VA_ARGS__ +#define IF_HAS_NO_KEYWORDS(...) +#else +#define HAS_KEYWORDS 0 +#define IF_HAS_KEYWORDS(...) +#define IF_HAS_NO_KEYWORDS(...) __VA_ARGS__ +#endif + + #define SPECIAL_VAR_SYMBOL 3 #define PARSEFLAG_EXIT_FROM_LOOP 1 @@ -276,18 +286,20 @@ struct p_context { struct pipe *list_head; struct pipe *pipe; struct redir_struct *pending_redirect; - smallint res_w; - smallint ctx_inverted; /* "! cmd | cmd" */ - int old_flag; /* bitmask of FLAG_xxx, for figuring out valid reserved words */ +#if HAS_KEYWORDS + smallint ctx_res_w; + smallint ctx_inverted; /* "! cmd | cmd" */ + int old_flag; /* bitmask of FLAG_xxx, for figuring out valid reserved words */ struct p_context *stack; +#endif }; struct redir_struct { struct redir_struct *next; - smallint /*redir_type*/ rd_type; + char *rd_filename; /* filename */ int fd; /* file descriptor being redirected */ int dup; /* -1, or file descriptor being duplicated */ - char *rd_filename; /* filename */ + smallint /*enum redir_type*/ rd_type; }; struct child_prog { @@ -317,9 +329,9 @@ struct pipe { char *cmdtext; /* name of job */ #endif struct child_prog *progs; /* array of commands in pipe */ - smallint pi_inverted; /* "! cmd | cmd" */ smallint followup; /* PIPE_BG, PIPE_SEQ, PIPE_OR, PIPE_AND */ - smallint res_word; /* needed for if, for, while, until... */ + IF_HAS_KEYWORDS(smallint pi_inverted;) /* "! cmd | cmd" */ + IF_HAS_KEYWORDS(smallint res_word;) /* needed for if, for, while, until... */ }; /* On program start, environ points to initial environment. @@ -1629,8 +1641,7 @@ static int checkjobs(struct pipe* fg_pipe) if (i == fg_pipe->num_progs - 1) { /* last process gives overall exitstatus */ rcode = WEXITSTATUS(status); - if (fg_pipe->pi_inverted) - rcode = !rcode; + IF_HAS_KEYWORDS(if (fg_pipe->pi_inverted) rcode = !rcode;) } } else { fg_pipe->progs[i].is_stopped = 1; @@ -1757,8 +1768,7 @@ static int run_pipe(struct pipe *pi) rcode = run_list(child->group) & 0xff; restore_redirects(squirrel); debug_printf_exec("run_pipe return %d\n", rcode); - if (pi->pi_inverted) - rcode = !rcode; + IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) return rcode; } @@ -1801,8 +1811,7 @@ static int run_pipe(struct pipe *pi) free(argv_expanded); restore_redirects(squirrel); debug_printf_exec("run_pipe return %d\n", rcode); - if (pi->pi_inverted) - rcode = !rcode; + IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) return rcode; } } @@ -1819,8 +1828,7 @@ static int run_pipe(struct pipe *pi) free(argv_expanded); restore_redirects(squirrel); debug_printf_exec("run_pipe return %d\n", rcode); - if (pi->pi_inverted) - rcode = !rcode; + IF_HAS_KEYWORDS(if (pi->pi_inverted) rcode = !rcode;) return rcode; } } @@ -2003,8 +2011,7 @@ static int run_list(struct pipe *pi) #else enum { if_code = 0, next_if_code = 0 }; #endif -// TODO: rword and ->res_word are not needed if !LOOPS and !IF - reserved_style rword; + reserved_style rword IF_HAS_NO_KEYWORDS(= RES_NONE); reserved_style skip_more_for_this_rword = RES_XXXX; debug_printf_exec("run_list start lvl %d\n", run_list_level + 1); @@ -2075,7 +2082,8 @@ static int run_list(struct pipe *pi) #endif /* JOB */ for (; pi; pi = flag_restore ? rpipe : pi->next) { - rword = pi->res_word; + IF_HAS_KEYWORDS(rword = pi->res_word;) + IF_HAS_NO_KEYWORDS(rword = RES_NONE;) #if ENABLE_HUSH_LOOPS if (rword == RES_WHILE || rword == RES_UNTIL || rword == RES_FOR) { flag_restore = 0; @@ -2272,7 +2280,9 @@ static int free_pipe_list(struct pipe *head, int indent) struct pipe *pi, *next; for (pi = head; pi; pi = next) { +#if HAS_KEYWORDS debug_printf_clean("%s pipe reserved mode %d\n", indenter(indent), pi->res_word); +#endif rcode = free_pipe(pi, indent); debug_printf_clean("%s pipe followup code %d\n", indenter(indent), pi->followup); next = pi->next; @@ -2548,7 +2558,7 @@ static char *expand_string_to_string(const char *str) argv[0] = (char*)str; argv[1] = NULL; list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */ - if (ENABLE_HUSH_DEBUG) + if (HUSH_DEBUG) if (!list[0] || list[1]) bb_error_msg_and_die("BUG in varexp2"); /* actually, just move string 2*sizeof(char*) bytes back */ @@ -2567,7 +2577,7 @@ static char* expand_strvec_to_string(char **argv) if (list[0]) { int n = 1; while (list[n]) { - if (ENABLE_HUSH_DEBUG) + if (HUSH_DEBUG) if (list[n-1] + strlen(list[n-1]) + 1 != list[n]) bb_error_msg_and_die("BUG in varexp3"); list[n][-1] = ' '; /* TODO: or to ifs[0]? */ @@ -2747,8 +2757,7 @@ static struct pipe *new_pipe(void) struct pipe *pi; pi = xzalloc(sizeof(struct pipe)); /*pi->followup = 0; - deliberately invalid value */ - if (RES_NONE) - pi->res_word = RES_NONE; + /*pi->res_word = RES_NONE; - RES_NONE is 0 anyway */ return pi; } @@ -2769,7 +2778,7 @@ static void initialize_context(struct p_context *ctx) * Handles if, then, elif, else, fi, for, while, until, do, done. * case, function, and select are obnoxious, save those for later. */ -#if ENABLE_HUSH_IF || ENABLE_HUSH_LOOPS +#if HAS_KEYWORDS static int reserved_word(const o_string *word, struct p_context *ctx) { struct reserved_combo { @@ -2828,18 +2837,18 @@ static int reserved_word(const o_string *word, struct p_context *ctx) debug_printf("found reserved word %s, res %d\n", r->literal, r->res); if (r->flag == 0) { /* '!' */ #if ENABLE_HUSH_LOOPS - if (ctx->res_w == RES_IN) { + if (ctx->ctx_res_w == RES_IN) { /* 'for a in ! a b c; ...' - ! isn't a keyword here */ break; } #endif if (ctx->ctx_inverted /* bash doesn't accept '! ! true' */ #if ENABLE_HUSH_LOOPS - || ctx->res_w == RES_FOR /* example: 'for ! a' */ + || ctx->ctx_res_w == RES_FOR /* example: 'for ! a' */ #endif ) { syntax(NULL); - ctx->res_w = RES_SNTX; + IF_HAS_KEYWORDS(ctx->ctx_res_w = RES_SNTX;) } ctx->ctx_inverted = 1; return 1; @@ -2848,9 +2857,9 @@ static int reserved_word(const o_string *word, struct p_context *ctx) struct p_context *new; debug_printf("push stack\n"); #if ENABLE_HUSH_LOOPS - if (ctx->res_w == RES_IN || ctx->res_w == RES_FOR) { + if (ctx->ctx_res_w == RES_IN || ctx->ctx_res_w == RES_FOR) { syntax("malformed for"); /* example: 'for if' */ - ctx->res_w = RES_SNTX; + ctx->ctx_res_w = RES_SNTX; return 1; } #endif @@ -2858,12 +2867,12 @@ static int reserved_word(const o_string *word, struct p_context *ctx) *new = *ctx; /* physical copy */ initialize_context(ctx); ctx->stack = new; - } else if (ctx->res_w == RES_NONE || !(ctx->old_flag & (1 << r->res))) { + } else if (ctx->ctx_res_w == RES_NONE || !(ctx->old_flag & (1 << r->res))) { syntax(NULL); - ctx->res_w = RES_SNTX; + ctx->ctx_res_w = RES_SNTX; return 1; } - ctx->res_w = r->res; + ctx->ctx_res_w = r->res; ctx->old_flag = r->flag; if (ctx->old_flag & FLAG_END) { struct p_context *old; @@ -2879,8 +2888,6 @@ static int reserved_word(const o_string *word, struct p_context *ctx) } return 0; } -#else -#define reserved_word(word, ctx) ((int)0) #endif /* Word is complete, look at it and update parsing context. @@ -2914,15 +2921,17 @@ static int done_word(o_string *word, struct p_context *ctx) debug_printf_parse("done_word return 1: syntax error, groups and arglists don't mix\n"); return 1; } +#if HAS_KEYWORDS if (!child->argv) { /* if it's the first word... */ 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->res_w == RES_SNTX)); - return (ctx->res_w == RES_SNTX); + debug_printf_parse("done_word return %d\n", (ctx->ctx_res_w == RES_SNTX)); + return (ctx->ctx_res_w == RES_SNTX); } } +#endif if (word->nonnull /* we saw "xx" or 'xx' */ /* optimization: and if it's ("" or '') or ($v... or `cmd`...): */ && (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL) @@ -2942,7 +2951,7 @@ static int done_word(o_string *word, struct p_context *ctx) #if ENABLE_HUSH_LOOPS /* Force FOR to have just one word (variable name) */ - if (ctx->res_w == RES_FOR) + if (ctx->ctx_res_w == RES_FOR) done_pipe(ctx, PIPE_SEQ); #endif debug_printf_parse("done_word return 0\n"); @@ -2993,9 +3002,9 @@ static void done_pipe(struct p_context *ctx, pipe_style type) debug_printf_parse("done_pipe entered, followup %d\n", type); not_null = done_command(ctx); /* implicit closure of previous command */ ctx->pipe->followup = type; - ctx->pipe->res_word = ctx->res_w; - ctx->pipe->pi_inverted = ctx->ctx_inverted; - ctx->ctx_inverted = 0; + IF_HAS_KEYWORDS(ctx->pipe->res_word = ctx->ctx_res_w;) + IF_HAS_KEYWORDS(ctx->pipe->pi_inverted = ctx->ctx_inverted;) + IF_HAS_KEYWORDS(ctx->ctx_inverted = 0;) /* Without this check, even just on command line generates * tree of three NOPs (!). Which is harmless but annoying. * IOW: it is safe to do it unconditionally. @@ -3480,7 +3489,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx, //err chk? done_pipe(ctx, PIPE_SEQ); } - if (ctx->res_w == RES_NONE) { + if (!HAS_KEYWORDS IF_HAS_KEYWORDS(|| ctx->ctx_res_w == RES_NONE)) { debug_printf_parse("parse_stream return 0: end_trigger char found\n"); return 0; } @@ -3650,7 +3659,7 @@ static int parse_stream(o_string *dest, struct p_context *ctx, debug_printf_parse("parse_stream return 1: unexpected '}'\n"); return 1; default: - if (ENABLE_HUSH_DEBUG) + if (HUSH_DEBUG) bb_error_msg_and_die("BUG: unexpected %c\n", ch); } } /* while (1) */ @@ -3706,10 +3715,12 @@ static int parse_and_run_stream(struct in_str *inp, int parse_flag) * Example: "sleep 9999; echo TEST" + ctrl-C: * TEST should be printed */ rcode = parse_stream(&temp, &ctx, inp, ";\n"); +#if HAS_KEYWORDS if (rcode != 1 && ctx.old_flag != 0) { syntax(NULL); } - if (rcode != 1 && ctx.old_flag == 0) { +#endif + if (rcode != 1 IF_HAS_KEYWORDS(&& ctx.old_flag == 0)) { done_word(&temp, &ctx); done_pipe(&ctx, PIPE_SEQ); debug_print_tree(ctx.list_head, 0); @@ -3717,10 +3728,12 @@ static int parse_and_run_stream(struct in_str *inp, int parse_flag) run_and_free_list(ctx.list_head); } else { /* We arrive here also if rcode == 1 (error in parse_stream) */ +#if HAS_KEYWORDS if (ctx.old_flag != 0) { free(ctx.stack); o_reset(&temp); } +#endif /*temp.nonnull = 0; - o_free does it below */ /*temp.o_quote = 0; - o_free does it below */ free_pipe_list(ctx.list_head, /* indent: */ 0);