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authorDenis Vlasenko2008-07-06 10:01:13 +0000
committerDenis Vlasenko2008-07-06 10:01:13 +0000
commit733e3fbc2fb6eb0195cbcc02724d186b1b820df6 (patch)
tree81ba6758a3b20c84b56e42473d427368b9180c0d /shell/hush.c
parentd48e81f0cda73aca49cd852212a62e879cf35b86 (diff)
downloadbusybox-733e3fbc2fb6eb0195cbcc02724d186b1b820df6.zip
busybox-733e3fbc2fb6eb0195cbcc02724d186b1b820df6.tar.gz
hush: support "for if in do done then; do echo $if; done" case
function old new delta done_pipe 83 95 +12 parse_stream 1758 1764 +6 done_word 674 647 -27 ------------------------------------------------------------------------------ (add/remove: 0/0 grow/shrink: 2/1 up/down: 18/-27) Total: -9 bytes
Diffstat (limited to 'shell/hush.c')
-rw-r--r--shell/hush.c59
1 files changed, 35 insertions, 24 deletions
diff --git a/shell/hush.c b/shell/hush.c
index f38f375..c71ddb1 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -1344,7 +1344,7 @@ static int setup_redirects(struct child_prog *prog, int squirrel[])
if (redir->dup == -1) {
char *p;
mode = redir_table[redir->rd_type].mode;
-//TODO: check redir to names like '\\'
+//TODO: check redir for names like '\\'
p = expand_string_to_string(redir->rd_filename);
openfd = open_or_warn(p, mode);
free(p);
@@ -2854,17 +2854,7 @@ static int reserved_word(const o_string *word, struct p_context *ctx)
continue;
debug_printf("found reserved word %s, res %d\n", r->literal, r->res);
if (r->flag == 0) { /* '!' */
-#if ENABLE_HUSH_LOOPS
- 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->ctx_res_w == RES_FOR /* example: 'for ! a' */
-#endif
- ) {
+ if (ctx->ctx_inverted) { /* bash doesn't accept '! ! true' */
syntax(NULL);
IF_HAS_KEYWORDS(ctx->ctx_res_w = RES_SNTX;)
}
@@ -2885,7 +2875,7 @@ 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->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->ctx_res_w = RES_SNTX;
return 1;
@@ -2940,7 +2930,10 @@ static int done_word(o_string *word, struct p_context *ctx)
return 1;
}
#if HAS_KEYWORDS
- if (!child->argv) { /* if it's the first word... */
+ if (!child->argv /* if it's the first word... */
+ && ctx->ctx_res_w != RES_FOR /* ...not after FOR or IN */
+ && ctx->ctx_res_w != RES_IN
+ ) {
debug_printf_parse(": checking '%s' for reserved-ness\n", word->data);
if (reserved_word(word, ctx)) {
o_reset(word);
@@ -2953,9 +2946,9 @@ static int done_word(o_string *word, struct p_context *ctx)
if (word->nonnull /* word had "xx" or 'xx' at least as part of it. */
/* optimization: and if it's ("" or '') or ($v... or `cmd`...): */
&& (word->data[0] == '\0' || word->data[0] == SPECIAL_VAR_SYMBOL)
- /* (otherwise it's "abc".... and is already safe) */
+ /* (otherwise it's known to be not empty and is already safe) */
) {
- /* but exclude "$@" - it expands to no word despite "" */
+ /* exclude "$@" - it can expand to no word despite "" */
char *p = word->data;
while (p[0] == SPECIAL_VAR_SYMBOL
&& (p[1] & 0x7f) == '@'
@@ -2964,7 +2957,9 @@ static int done_word(o_string *word, struct p_context *ctx)
p += 3;
}
if (p == word->data || p[0] != '\0') {
- /* Insert "empty variable" reference, this makes
+ /* saw no "$@", or not only "$@" but some
+ * real text is there too */
+ /* insert "empty variable" reference, this makes
* e.g. "", $empty"" etc to not disappear */
o_addchr(word, SPECIAL_VAR_SYMBOL);
o_addchr(word, SPECIAL_VAR_SYMBOL);
@@ -2979,8 +2974,13 @@ 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->ctx_res_w == RES_FOR)
+ /* NB: basically, this makes hush see "for v in ..." syntax as if
+ * as it is "for v; in ...". FOR and IN become two pipe structs
+ * in parse tree. */
+ if (ctx->ctx_res_w == RES_FOR) {
+//TODO: check that child->argv[0] is a valid variable name!
done_pipe(ctx, PIPE_SEQ);
+ }
#endif
debug_printf_parse("done_word return 0\n");
return 0;
@@ -3030,19 +3030,28 @@ 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;
- 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;)
+ IF_HAS_KEYWORDS(ctx->pipe->res_word = ctx->ctx_res_w;)
/* Without this check, even just <enter> on command line generates
* tree of three NOPs (!). Which is harmless but annoying.
* IOW: it is safe to do it unconditionally.
- * RES_IN case is for "for a in; do ..." (empty IN set)
- * to work. */
- if (not_null USE_HUSH_LOOPS(|| ctx->pipe->res_word == RES_IN)) {
+ * RES_NONE case is for "for a in; do ..." (empty IN set)
+ * to work, possibly other cases too. */
+ if (not_null IF_HAS_KEYWORDS(|| ctx->ctx_res_w != RES_NONE)) {
struct pipe *new_p = new_pipe();
ctx->pipe->next = new_p;
ctx->pipe = new_p;
ctx->child = NULL; /* needed! */
+ /* RES_IF, RES_WHILE etc are "sticky" -
+ * they remain set for commands inside if/while.
+ * This is used to control execution.
+ * RES_FOR and RES_IN are NOT sticky (needed to support
+ * cases where variable or value happens to match a keyword):
+ */
+ if (ctx->ctx_res_w == RES_FOR
+ || ctx->ctx_res_w == RES_IN)
+ ctx->ctx_res_w = RES_NONE;
/* Create the memory for child, roughly:
* ctx->pipe->progs = new struct child_prog;
* ctx->pipe->progs[0].family = ctx->pipe;
@@ -3444,7 +3453,7 @@ static int handle_dollar(o_string *dest, struct in_str *input)
return 0;
}
-/* Scan input, call done_word() whenever full IFS delemited word was seen.
+/* Scan input, call done_word() whenever full IFS delimited word was seen.
* call done_pipe if '\n' was seen (and end_trigger != NULL)
* Return if (non-quoted) char in end_trigger was seen; or on parse error. */
/* Return code is 0 if end_trigger char is met,
@@ -3517,7 +3526,9 @@ static int parse_stream(o_string *dest, struct p_context *ctx,
//err chk?
done_pipe(ctx, PIPE_SEQ);
}
- if (!HAS_KEYWORDS IF_HAS_KEYWORDS(|| ctx->ctx_res_w == RES_NONE)) {
+ if (!HAS_KEYWORDS
+ IF_HAS_KEYWORDS(|| (ctx->ctx_res_w == RES_NONE && ctx->old_flag == 0))
+ ) {
debug_printf_parse("parse_stream return 0: end_trigger char found\n");
return 0;
}