svn commit: trunk/busybox/shell
vda at busybox.net
vda at busybox.net
Sat May 5 08:10:52 PDT 2007
Author: vda
Date: 2007-05-05 08:10:52 -0700 (Sat, 05 May 2007)
New Revision: 18560
Log:
hush: preparatory patch for removing extra empty pipes generation
in parse stage. No real code change here.
Modified:
trunk/busybox/shell/hush.c
Changeset:
Modified: trunk/busybox/shell/hush.c
===================================================================
--- trunk/busybox/shell/hush.c 2007-05-04 21:38:14 UTC (rev 18559)
+++ trunk/busybox/shell/hush.c 2007-05-05 15:10:52 UTC (rev 18560)
@@ -125,10 +125,10 @@
#define ENABLE_FEATURE_EDITING_FANCY_PROMPT 0
#endif
-#define SPECIAL_VAR_SYMBOL 03
-#define FLAG_EXIT_FROM_LOOP 1
+#define SPECIAL_VAR_SYMBOL 3
+#define FLAG_EXIT_FROM_LOOP 1
#define FLAG_PARSE_SEMICOLON (1 << 1) /* symbol ';' is special for parser */
-#define FLAG_REPARSING (1 << 2) /* >=2nd pass */
+#define FLAG_REPARSING (1 << 2) /* >= 2nd pass */
typedef enum {
REDIRECT_INPUT = 1,
@@ -199,10 +199,10 @@
struct pipe *list_head;
struct pipe *pipe;
struct redir_struct *pending_redirect;
- reserved_style w;
- int old_flag; /* for figuring out valid reserved words */
+ reserved_style res_w;
+ int old_flag; /* for figuring out valid reserved words */
struct p_context *stack;
- int type; /* define type of parser : ";$" common or special symbol */
+ int parse_type; /* define type of parser : ";$" common or special symbol */
/* How about quoting status? */
};
@@ -410,8 +410,8 @@
static int parse_string(o_string *dest, struct p_context *ctx, const char *src);
static int parse_stream(o_string *dest, struct p_context *ctx, struct in_str *input0, const char *end_trigger);
/* setup: */
-static int parse_stream_outer(struct in_str *inp, int flag);
-static int parse_string_outer(const char *s, int flag);
+static int parse_stream_outer(struct in_str *inp, int parse_flag);
+static int parse_string_outer(const char *s, int parse_flag);
static int parse_file_outer(FILE *f);
/* job management: */
static int checkjobs(struct pipe* fg_pipe);
@@ -1854,23 +1854,24 @@
};
int pin, prn;
- char **argv;
pin = 0;
while (pi) {
fprintf(stderr, "%*spipe %d r_mode=%s followup=%d %s\n", lvl*2, "",
pin, RES[pi->r_mode], pi->followup, PIPE[pi->followup]);
prn = 0;
while (prn < pi->num_progs) {
+ struct child_prog *child = &pi->progs[prn];
+ char **argv = child->argv;
+
fprintf(stderr, "%*s prog %d", lvl*2, "", prn);
- if (pi->progs[prn].group) {
+ if (child->group) {
fprintf(stderr, " group %s: (argv=%p)\n",
- (pi->subshell ? "()" : "{}"),
- pi->progs[prn].argv);
- debug_print_tree(pi->progs[prn].group, lvl+1);
+ (child->subshell ? "()" : "{}"),
+ argv);
+ debug_print_tree(child->group, lvl+1);
prn++;
continue;
}
- argv = pi->progs[prn].argv;
if (argv) while (*argv) {
fprintf(stderr, " '%s'", *argv);
argv++;
@@ -1901,7 +1902,7 @@
int flag_rep = 0;
int save_num_progs;
int flag_skip = 1;
- int rcode = 0; /* probaly for gcc only */
+ int rcode = 0; /* probably for gcc only */
int flag_restore = 0;
int if_code = 0, next_if_code = 0; /* need double-buffer to handle elif */
reserved_style rmode, skip_more_in_this_rmode = RES_XXXX;
@@ -1968,17 +1969,15 @@
}
#endif
- for (; pi; pi = (flag_restore != 0) ? rpipe : pi->next) {
- if (pi->r_mode == RES_WHILE || pi->r_mode == RES_UNTIL
- || pi->r_mode == RES_FOR
- ) {
+ for (; pi; pi = flag_restore ? rpipe : pi->next) {
+ rmode = pi->r_mode;
+ if (rmode == RES_WHILE || rmode == RES_UNTIL || rmode == RES_FOR) {
flag_restore = 0;
if (!rpipe) {
flag_rep = 0;
rpipe = pi;
}
}
- rmode = pi->r_mode;
debug_printf_exec(": rmode=%d if_code=%d next_if_code=%d skip_more=%d\n",
rmode, if_code, next_if_code, skip_more_in_this_rmode);
if (rmode == skip_more_in_this_rmode && flag_skip) {
@@ -2535,7 +2534,7 @@
ctx->child = NULL;
ctx->list_head = new_pipe();
ctx->pipe = ctx->list_head;
- ctx->w = RES_NONE;
+ ctx->res_w = RES_NONE;
ctx->stack = NULL;
ctx->old_flag = 0;
done_command(ctx); /* creates the memory for working child */
@@ -2574,29 +2573,29 @@
enum { NRES = sizeof(reserved_list)/sizeof(reserved_list[0]) };
const struct reserved_combo *r;
- for (r = reserved_list; r < reserved_list+NRES; r++) {
+ for (r = reserved_list; r < reserved_list + NRES; r++) {
if (strcmp(dest->data, r->literal) == 0) {
debug_printf("found reserved word %s, code %d\n", r->literal, r->code);
if (r->flag & FLAG_START) {
struct p_context *new = xmalloc(sizeof(struct p_context));
debug_printf("push stack\n");
- if (ctx->w == RES_IN || ctx->w == RES_FOR) {
+ if (ctx->res_w == RES_IN || ctx->res_w == RES_FOR) {
syntax();
free(new);
- ctx->w = RES_SNTX;
+ ctx->res_w = RES_SNTX;
b_reset(dest);
return 1;
}
*new = *ctx; /* physical copy */
initialize_context(ctx);
ctx->stack = new;
- } else if (ctx->w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
+ } else if (ctx->res_w == RES_NONE || !(ctx->old_flag & (1 << r->code))) {
syntax();
- ctx->w = RES_SNTX;
+ ctx->res_w = RES_SNTX;
b_reset(dest);
return 1;
}
- ctx->w = r->code;
+ ctx->res_w = r->code;
ctx->old_flag = r->flag;
if (ctx->old_flag & FLAG_END) {
struct p_context *old;
@@ -2623,7 +2622,7 @@
glob_t *glob_target;
int gr, flags = 0;
- debug_printf_parse("done_word: '%s' %p\n", dest->data, child);
+ debug_printf_parse("done_word entered: '%s' %p\n", dest->data, child);
if (dest->length == 0 && !dest->nonnull) {
debug_printf_parse("done_word return 0: true null, ignored\n");
return 0;
@@ -2636,15 +2635,16 @@
debug_printf_parse("done_word return 1: syntax error, groups and arglists don't mix\n");
return 1;
}
- if (!child->argv && (ctx->type & FLAG_PARSE_SEMICOLON)) {
- debug_printf_parse(": checking %s for reserved-ness\n", dest->data);
+ if (!child->argv && (ctx->parse_type & FLAG_PARSE_SEMICOLON)) {
+ debug_printf_parse(": checking '%s' for reserved-ness\n", dest->data);
if (reserved_word(dest, ctx)) {
- debug_printf_parse("done_word return %d\n", (ctx->w == RES_SNTX));
- return (ctx->w == RES_SNTX);
+ debug_printf_parse("done_word return %d\n", (ctx->res_w == RES_SNTX));
+ return (ctx->res_w == RES_SNTX);
}
}
glob_target = &child->glob_result;
- if (child->argv) flags |= GLOB_APPEND;
+ if (child->argv)
+ flags |= GLOB_APPEND;
}
gr = xglob(dest, flags, glob_target);
if (gr != 0) {
@@ -2663,7 +2663,7 @@
} else {
child->argv = glob_target->gl_pathv;
}
- if (ctx->w == RES_FOR) {
+ if (ctx->res_w == RES_FOR) {
done_word(dest, ctx);
done_pipe(ctx, PIPE_SEQ);
}
@@ -2676,56 +2676,63 @@
static int done_command(struct p_context *ctx)
{
/* The child is really already in the pipe structure, so
- * advance the pipe counter and make a new, null child.
- * Only real trickiness here is that the uncommitted
- * child structure, to which ctx->child points, is not
- * counted in pi->num_progs. */
+ * advance the pipe counter and make a new, null child. */
struct pipe *pi = ctx->pipe;
- struct child_prog *prog = ctx->child;
+ struct child_prog *child = ctx->child;
- if (prog && prog->group == NULL
- && prog->argv == NULL
- && prog->redirects == NULL
- ) {
- debug_printf("done_command: skipping null command\n");
- return 0;
- }
- if (prog) {
+ if (child) {
+ if (child->group == NULL
+ && child->argv == NULL
+ && child->redirects == NULL
+ ) {
+ debug_printf_parse("done_command: skipping null command\n");
+ return 0;
+ }
pi->num_progs++;
- debug_printf("done_command: num_progs incremented to %d\n", pi->num_progs);
+ debug_printf_parse("done_command: ++num_progs=%d\n", pi->num_progs);
} else {
- debug_printf("done_command: initializing\n");
+ debug_printf_parse("done_command: initializing, num_progs=%d\n", pi->num_progs);
}
+
+ /* Only real trickiness here is that the uncommitted
+ * child structure is not counted in pi->num_progs. */
pi->progs = xrealloc(pi->progs, sizeof(*pi->progs) * (pi->num_progs+1));
+ child = &pi->progs[pi->num_progs];
- prog = pi->progs + pi->num_progs;
- memset(prog, 0, sizeof(*prog));
- /*prog->redirects = NULL;*/
- /*prog->argv = NULL; */
- /*prog->is_stopped = 0;*/
- /*prog->group = NULL;*/
- /*prog->glob_result.gl_pathv = NULL;*/
- prog->family = pi;
- /*prog->sp = 0;*/
- ctx->child = prog;
- prog->type = ctx->type;
+ memset(child, 0, sizeof(*child));
+ /*child->redirects = NULL;*/
+ /*child->argv = NULL;*/
+ /*child->is_stopped = 0;*/
+ /*child->group = NULL;*/
+ /*child->glob_result.gl_pathv = NULL;*/
+ child->family = pi;
+ /*child->sp = 0;*/
+ child->type = ctx->parse_type;
+ ctx->child = child;
/* but ctx->pipe and ctx->list_head remain unchanged */
+
return 0;
}
static int done_pipe(struct p_context *ctx, pipe_style type)
{
struct pipe *new_p;
+
+ debug_printf_parse("done_pipe entered, followup %d\n", type);
done_command(ctx); /* implicit closure of previous command */
- debug_printf_parse("done_pipe, type %d\n", type);
ctx->pipe->followup = type;
- ctx->pipe->r_mode = ctx->w;
+ ctx->pipe->r_mode = ctx->res_w;
new_p = new_pipe();
ctx->pipe->next = new_p;
ctx->pipe = new_p;
ctx->child = NULL;
+// TODO: even just <enter> on command line basically generates
+// tree of three NOPs (!).
+// Can we detect that previous done_command have seen "skipping null command"
+// condition and NOT create new pipe here?
done_command(ctx); /* set up new pipe to accept commands */
+ debug_printf_parse("done_pipe return 0\n");
return 0;
}
@@ -3055,7 +3062,7 @@
}
if (m == MAP_IFS_IF_UNQUOTED) {
if (done_word(dest, ctx)) {
- debug_printf_parse("parse_stream return 1\n");
+ debug_printf_parse("parse_stream return 1: done_word!=0\n");
return 1;
}
/* If we aren't performing a substitution, treat
@@ -3066,9 +3073,9 @@
}
}
if ((end_trigger && strchr(end_trigger, ch))
- && !dest->quote && ctx->w == RES_NONE
+ && !dest->quote && ctx->res_w == RES_NONE
) {
- debug_printf_parse("parse_stream return 0\n");
+ debug_printf_parse("parse_stream return 0: end_trigger char found\n");
return 0;
}
if (m == MAP_IFS_IF_UNQUOTED)
@@ -3089,7 +3096,7 @@
case '\\':
if (next == EOF) {
syntax();
- debug_printf_parse("parse_stream return 1\n");
+ debug_printf_parse("parse_stream return 1: \\<eof>\n");
return 1;
}
b_addqchr(dest, '\\', dest->quote);
@@ -3111,7 +3118,7 @@
}
if (ch == EOF) {
syntax();
- debug_printf_parse("parse_stream return 1\n");
+ debug_printf_parse("parse_stream return 1: unterminated '\n");
return 1;
}
break;
@@ -3204,7 +3211,7 @@
* that is, we were really supposed to get end_trigger, and never got
* one before the EOF. Can't use the standard "syntax error" return code,
* so that parse_stream_outer can distinguish the EOF and exit smoothly. */
- debug_printf_parse("parse_stream return -%d\n", end_trigger != NULL);
+ debug_printf_parse("parse_stream return %d\n", -(end_trigger != NULL));
if (end_trigger)
return -1;
return 0;
@@ -3220,7 +3227,8 @@
{
/* char *ifs and char map[256] are both globals. */
ifs = getenv("IFS");
- if (ifs == NULL) ifs = " \t\n";
+ if (ifs == NULL)
+ ifs = " \t\n";
/* Precompute a list of 'flow through' behavior so it can be treated
* quickly up front. Computation is necessary because of IFS.
* Special case handling of IFS == " \t\n" is not implemented.
@@ -3235,24 +3243,26 @@
/* most recursion does not come through here, the exception is
* from builtin_source() */
-static int parse_stream_outer(struct in_str *inp, int flag)
+static int parse_stream_outer(struct in_str *inp, int parse_flag)
{
// FIXME: '{ true | exit 3; echo $? }' is parsed as a whole,
// as a result $? is replaced by 0, not 3!
-// Need to stop & execute stuff at ';', not parse till EOL!
struct p_context ctx;
o_string temp = NULL_O_STRING;
int rcode;
do {
- ctx.type = flag;
+ ctx.parse_type = parse_flag;
initialize_context(&ctx);
update_ifs_map();
- if (!(flag & FLAG_PARSE_SEMICOLON) || (flag & FLAG_REPARSING))
+ if (!(parse_flag & FLAG_PARSE_SEMICOLON) || (parse_flag & FLAG_REPARSING))
mapset(";$&|", MAP_ORDINARY);
#if ENABLE_HUSH_INTERACTIVE
inp->promptmode = 1;
#endif
+ /* We will stop & execute after each ';' or '\n'.
+ * Example: "sleep 9999; echo TEST" + ctrl-C:
+ * TEST should be printed */
rcode = parse_stream(&temp, &ctx, inp, ";\n");
if (rcode != 1 && ctx.old_flag != 0) {
syntax();
@@ -3274,15 +3284,15 @@
free_pipe_list(ctx.list_head, 0);
}
b_free(&temp);
- } while (rcode != -1 && !(flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
+ } while (rcode != -1 && !(parse_flag & FLAG_EXIT_FROM_LOOP)); /* loop on syntax errors, return on EOF */
return 0;
}
-static int parse_string_outer(const char *s, int flag)
+static int parse_string_outer(const char *s, int parse_flag)
{
struct in_str input;
setup_string_in_str(&input, s);
- return parse_stream_outer(&input, flag);
+ return parse_stream_outer(&input, parse_flag);
}
static int parse_file_outer(FILE *f)
@@ -3303,7 +3313,7 @@
pid_t shell_pgrp;
saved_task_pgrp = shell_pgrp = getpgrp();
- debug_printf("saved_task_pgrp=%d\n", saved_task_pgrp);
+ debug_printf_jobs("saved_task_pgrp=%d\n", saved_task_pgrp);
fcntl(interactive_fd, F_SETFD, FD_CLOEXEC);
/* If we were ran as 'hush &',
@@ -3319,7 +3329,7 @@
set_misc_sighandler(SIG_IGN);
//huh? signal(SIGCHLD, SIG_IGN);
- /* We _must_ restore tty pgrp fatal signals */
+ /* We _must_ restore tty pgrp on fatal signals */
set_fatal_sighandler(sigexit);
/* Put ourselves in our own process group. */
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