From c373527e4fe7d2d46ce25165687463da00ba986c Mon Sep 17 00:00:00 2001 From: Denis Vlasenko Date: Thu, 9 Oct 2008 12:58:26 +0000 Subject: [PATCH] hush: preparatory work for implementing functions --- shell/hush.c | 155 +++++++++++++++++++++++++++++---------------------- 1 file changed, 89 insertions(+), 66 deletions(-) diff --git a/shell/hush.c b/shell/hush.c index c26b9e420..d5955dd93 100644 --- a/shell/hush.c +++ b/shell/hush.c @@ -2903,37 +2903,38 @@ static void initialize_context(struct parse_context *ctx) * case, function, and select are obnoxious, save those for later. */ #if HAS_KEYWORDS -static int reserved_word(o_string *word, struct parse_context *ctx) -{ - struct reserved_combo { - char literal[6]; - unsigned char res; - unsigned char assignment_flag; - int flag; - }; - enum { - FLAG_END = (1 << RES_NONE ), +struct reserved_combo { + char literal[6]; + unsigned char res; + unsigned char assignment_flag; + int flag; +}; +enum { + FLAG_END = (1 << RES_NONE ), #if ENABLE_HUSH_IF - FLAG_IF = (1 << RES_IF ), - FLAG_THEN = (1 << RES_THEN ), - FLAG_ELIF = (1 << RES_ELIF ), - FLAG_ELSE = (1 << RES_ELSE ), - FLAG_FI = (1 << RES_FI ), + FLAG_IF = (1 << RES_IF ), + FLAG_THEN = (1 << RES_THEN ), + FLAG_ELIF = (1 << RES_ELIF ), + FLAG_ELSE = (1 << RES_ELSE ), + FLAG_FI = (1 << RES_FI ), #endif #if ENABLE_HUSH_LOOPS - FLAG_FOR = (1 << RES_FOR ), - FLAG_WHILE = (1 << RES_WHILE), - FLAG_UNTIL = (1 << RES_UNTIL), - FLAG_DO = (1 << RES_DO ), - FLAG_DONE = (1 << RES_DONE ), - FLAG_IN = (1 << RES_IN ), + FLAG_FOR = (1 << RES_FOR ), + FLAG_WHILE = (1 << RES_WHILE), + FLAG_UNTIL = (1 << RES_UNTIL), + FLAG_DO = (1 << RES_DO ), + FLAG_DONE = (1 << RES_DONE ), + FLAG_IN = (1 << RES_IN ), #endif #if ENABLE_HUSH_CASE - FLAG_MATCH = (1 << RES_MATCH), - FLAG_ESAC = (1 << RES_ESAC ), + FLAG_MATCH = (1 << RES_MATCH), + FLAG_ESAC = (1 << RES_ESAC ), #endif - FLAG_START = (1 << RES_XXXX ), - }; + FLAG_START = (1 << RES_XXXX ), +}; + +static const struct reserved_combo* match_reserved_word(o_string *word) +{ /* Mostly a list of accepted follow-up reserved words. * FLAG_END means we are done with the sequence, and are ready * to turn the compound list into a command. @@ -2961,6 +2962,16 @@ static int reserved_word(o_string *word, struct parse_context *ctx) { "esac", RES_ESAC, NOT_ASSIGNMENT , FLAG_END }, #endif }; + const struct reserved_combo *r; + + for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) { + if (strcmp(word->data, r->literal) == 0) + return r; + } + return NULL; +} +static int reserved_word(o_string *word, struct parse_context *ctx) +{ #if ENABLE_HUSH_CASE static const struct reserved_combo reserved_match = { "", RES_MATCH, NOT_ASSIGNMENT , FLAG_MATCH | FLAG_ESAC @@ -2968,52 +2979,51 @@ static int reserved_word(o_string *word, struct parse_context *ctx) #endif const struct reserved_combo *r; - for (r = reserved_list; r < reserved_list + ARRAY_SIZE(reserved_list); r++) { - if (strcmp(word->data, r->literal) != 0) - continue; - debug_printf("found reserved word %s, res %d\n", r->literal, r->res); + r = match_reserved_word(word); + if (!r) + return 0; + + debug_printf("found reserved word %s, res %d\n", r->literal, r->res); #if ENABLE_HUSH_CASE - if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE) - /* "case word IN ..." - IN part starts first match part */ - r = &reserved_match; - else + if (r->res == RES_IN && ctx->ctx_res_w == RES_CASE) + /* "case word IN ..." - IN part starts first match part */ + r = &reserved_match; + else #endif - if (r->flag == 0) { /* '!' */ - if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */ - syntax(NULL); - IF_HAS_KEYWORDS(ctx->ctx_res_w = RES_SNTX;) - } - ctx->ctx_inverted = 1; - return 1; - } - if (r->flag & FLAG_START) { - struct parse_context *new; - debug_printf("push stack\n"); - new = xmalloc(sizeof(*new)); - *new = *ctx; /* physical copy */ - initialize_context(ctx); - ctx->stack = new; - } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) { + if (r->flag == 0) { /* '!' */ + if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */ syntax(NULL); - ctx->ctx_res_w = RES_SNTX; - return 1; - } - ctx->ctx_res_w = r->res; - ctx->old_flag = r->flag; - if (ctx->old_flag & FLAG_END) { - struct parse_context *old; - debug_printf("pop stack\n"); - done_pipe(ctx, PIPE_SEQ); - old = ctx->stack; - old->command->group = ctx->list_head; - old->command->subshell = 0; - *ctx = *old; /* physical copy */ - free(old); + IF_HAS_KEYWORDS(ctx->ctx_res_w = RES_SNTX;) } - word->o_assignment = r->assignment_flag; + ctx->ctx_inverted = 1; return 1; } - return 0; + if (r->flag & FLAG_START) { + struct parse_context *new; + debug_printf("push stack\n"); + new = xmalloc(sizeof(*new)); + *new = *ctx; /* physical copy */ + initialize_context(ctx); + ctx->stack = new; + } else if (/*ctx->ctx_res_w == RES_NONE ||*/ !(ctx->old_flag & (1 << r->res))) { + syntax(NULL); + ctx->ctx_res_w = RES_SNTX; + return 1; + } + ctx->ctx_res_w = r->res; + ctx->old_flag = r->flag; + if (ctx->old_flag & FLAG_END) { + struct parse_context *old; + debug_printf("pop stack\n"); + done_pipe(ctx, PIPE_SEQ); + old = ctx->stack; + old->command->group = ctx->list_head; + old->command->subshell = 0; + *ctx = *old; /* physical copy */ + free(old); + } + word->o_assignment = r->assignment_flag; + return 1; } #endif @@ -3892,6 +3902,17 @@ static int parse_stream(o_string *dest, struct parse_context *ctx, ) { continue; } +#endif +#if 0 /* TODO: implement functions */ + if (dest->length != 0 /* not just () but word() */ + && dest->nonnull == 0 /* not a"b"c() */ + && ctx->command->argv == NULL /* it's the first word */ + && i_peek(input) == ')' + ) { + bb_error_msg("seems like a function definition"); + if (match_reserved_word(dest)) + bb_error_msg("but '%s' is a reserved word!", dest->data); + } #endif case '{': if (parse_group(dest, ctx, input, ch) != 0) { @@ -3905,7 +3926,9 @@ static int parse_stream(o_string *dest, struct parse_context *ctx, goto case_semi; #endif case '}': - /* proper use of this character is caught by end_trigger */ + /* proper use of this character is caught by end_trigger: + * if we see {, we call parse_group(..., end_trigger='}') + * and it will match } earlier (not here). */ syntax("unexpected } or )"); debug_printf_parse("parse_stream return 1: unexpected '}'\n"); return 1; -- 2.25.1