svn commit: trunk/busybox/shell
vda at busybox.net
vda at busybox.net
Thu May 17 14:38:17 UTC 2007
Author: vda
Date: 2007-05-17 07:38:17 -0700 (Thu, 17 May 2007)
New Revision: 18641
Log:
hush: consolidated variable expansion for assignments and "normal" one.
-435 bytes. Tested against testsuite.
Modified:
trunk/busybox/shell/hush.c
Changeset:
Modified: trunk/busybox/shell/hush.c
===================================================================
--- trunk/busybox/shell/hush.c 2007-05-17 13:02:41 UTC (rev 18640)
+++ trunk/busybox/shell/hush.c 2007-05-17 14:38:17 UTC (rev 18641)
@@ -444,8 +444,9 @@
int checkjobs_and_fg_shell(struct pipe* fg_pipe); /* never called */
#endif
/* local variable support */
-static char **do_variable_expansion(char **argv);
-static char *insert_var_value(char *inp);
+static char **expand_variables_to_list(char **argv);
+/* used for expansion of right hand of assignments */
+static char *expand_variables_to_string(const char *str);
static const char *get_local_var(const char *var);
static int set_local_var(const char *s, int flg_export);
static void unset_local_var(const char *name);
@@ -1271,7 +1272,7 @@
debug_printf_exec("pid %d environment modification: %s\n",
getpid(), argv[i]);
// FIXME: vfork case??
- p = insert_var_value(argv[i]);
+ p = expand_variables_to_string(argv[i]);
putenv(p == argv[i] ? xstrdup(p) : p);
}
argv += i;
@@ -1282,7 +1283,7 @@
_exit(EXIT_SUCCESS);
}
- argv = do_variable_expansion(argv);
+ argv = expand_variables_to_list(argv);
/*
* Check if the command matches any of the builtins.
@@ -1667,7 +1668,7 @@
export_me = 1;
}
free(name);
- p = insert_var_value(argv[i]);
+ p = expand_variables_to_string(argv[i]);
set_local_var(p, export_me);
if (p != argv[i])
free(p);
@@ -1675,7 +1676,7 @@
return EXIT_SUCCESS; /* don't worry about errors in set_local_var() yet */
}
for (i = 0; is_assignment(argv[i]); i++) {
- p = insert_var_value(argv[i]);
+ p = expand_variables_to_string(argv[i]);
if (p != argv[i]) {
//sp: child->sp--;
putenv(p);
@@ -1698,7 +1699,7 @@
setup_redirects(child, squirrel);
debug_printf_exec(": builtin '%s' '%s'...\n", x->cmd, argv[i+1]);
//sp: if (child->sp) /* btw we can do it unconditionally... */
- argv_expanded = do_variable_expansion(argv + i);
+ argv_expanded = expand_variables_to_list(argv + i);
rcode = x->function(argv_expanded);
free(argv_expanded);
restore_redirects(squirrel);
@@ -1714,7 +1715,7 @@
save_nofork_data(&nofork_save);
argv_expanded = argv + i;
//sp: if (child->sp)
- argv_expanded = do_variable_expansion(argv + i);
+ argv_expanded = expand_variables_to_list(argv + i);
debug_printf_exec(": run_nofork_applet '%s' '%s'...\n", argv_expanded[0], argv_expanded[1]);
rcode = run_nofork_applet_prime(&nofork_save, a, argv_expanded);
free(argv_expanded);
@@ -1991,7 +1992,7 @@
if (!pi->next->progs->argv)
continue;
/* create list of variable values */
- for_list = do_variable_expansion(pi->next->progs->argv);
+ for_list = expand_variables_to_list(pi->next->progs->argv);
for_lcur = for_list;
for_varname = pi->progs->argv[0];
pi->progs->argv[0] = NULL;
@@ -2251,8 +2252,7 @@
return gr;
}
-
-/* do_variable_expansion() takes a list of strings, expands
+/* expand_variables_to_list() takes a list of strings, expands
* all variable references within and returns a pointer to
* a list of expanded strings, possibly with larger number
* of strings. (Think VAR="a b"; echo $VAR).
@@ -2371,8 +2371,11 @@
* 'echo -$*-'. If you play here, you must run testsuite afterwards! */
/* NB: another bug is that we cannot detect empty strings yet:
* "" or $empty"" expands to zero words, has to expand to empty word */
-static int expand_vars_to_list(char **list, int n, char **posp, char *arg)
+static int expand_vars_to_list(char **list, int n, char **posp, char *arg, char or_mask)
{
+ /* or_mask is either 0 (normal case) or 0x80
+ * (expansion of right-hand side of assignment == 1-element expand) */
+
char first_ch, ored_ch;
int i;
const char *val;
@@ -2392,7 +2395,7 @@
arg = ++p;
p = strchr(p, SPECIAL_VAR_SYMBOL);
- first_ch = arg[0];
+ first_ch = arg[0] | or_mask; /* forced to "quoted" if or_mask = 0x80 */
ored_ch |= first_ch;
val = NULL;
switch (first_ch & 0x7f) {
@@ -2427,7 +2430,10 @@
list[n++] = pos;
}
}
- } else if (first_ch == ('@'|0x80)) { /* quoted $@ */
+ } else
+ /* If or_mask is nonzero, we handle assignment 'a=....$@.....'
+ * and in this case should theat it like '$*' */
+ if (first_ch == ('@'|0x80) && !or_mask) { /* quoted $@ */
while (1) {
strcpy(pos, global_argv[i]);
pos += strlen(global_argv[i]);
@@ -2490,7 +2496,7 @@
return n;
}
-static char **do_variable_expansion(char **argv)
+static char **expand_variables(char **argv, char or_mask)
{
int n;
int count = 1;
@@ -2515,9 +2521,9 @@
n = 0;
v = argv;
while (*v)
- n = expand_vars_to_list(list, n, &pos, *v++);
+ n = expand_vars_to_list(list, n, &pos, *v++, or_mask);
- if(n) debug_printf_expand("finalized list[%d]=%p '%s' "
+ if (n) debug_printf_expand("finalized list[%d]=%p '%s' "
"strlen=%d next=%p pos=%p\n", n-1, list[n-1], list[n-1],
strlen(list[n-1]), list[n-1] + strlen(list[n-1]) + 1, pos);
list[n] = NULL;
@@ -2538,80 +2544,26 @@
return list;
}
+static char **expand_variables_to_list(char **argv)
+{
+ return expand_variables(argv, 0);
+}
-static char *insert_var_value(char *inp)
+static char *expand_variables_to_string(const char *str)
{
- int res_str_len = 0;
- int len;
- int done = 0;
- int i;
- const char *p1;
- char *p, *p2;
- char *res_str = NULL;
+ char *argv[2], **list;
- while ((p = strchr(inp, SPECIAL_VAR_SYMBOL))) {
- if (p != inp) {
- len = p - inp;
- res_str = xrealloc(res_str, (res_str_len + len));
- strncpy((res_str + res_str_len), inp, len);
- res_str_len += len;
- }
- inp = ++p;
- p = strchr(inp, SPECIAL_VAR_SYMBOL);
- *p = '\0';
-
- switch (inp[0]) {
- case '$':
- /* FIXME: (echo $$) should still print pid of main shell */
- p1 = utoa(getpid());
- break;
- case '!':
- p1 = last_bg_pid ? utoa(last_bg_pid) : (char*)"";
- break;
- case '?':
- p1 = utoa(last_return_code);
- break;
- case '#':
- p1 = utoa(global_argc ? global_argc-1 : 0);
- break;
- case '*':
- case '@': /* FIXME: we treat $@ as $* for now */
- len = 1;
- for (i = 1; i < global_argc; i++)
- len += strlen(global_argv[i]) + 1;
- p1 = p2 = alloca(--len);
- for (i = 1; i < global_argc; i++) {
- strcpy(p2, global_argv[i]);
- p2 += strlen(global_argv[i]);
- *p2++ = ifs[0];
- }
- *--p2 = '\0';
- break;
- default:
- p1 = lookup_param(inp);
- }
-
- if (p1) {
- len = res_str_len + strlen(p1);
- res_str = xrealloc(res_str, 1 + len);
- strcpy(res_str + res_str_len, p1);
- res_str_len = len;
- }
- *p = SPECIAL_VAR_SYMBOL;
- inp = ++p;
- done = 1;
- }
- if (done) {
- res_str = xrealloc(res_str, (1 + res_str_len + strlen(inp)));
- strcpy((res_str + res_str_len), inp);
- while ((p = strchr(res_str, '\n'))) {
- *p = ' ';
- }
- }
- return (res_str == NULL) ? inp : res_str;
+ argv[0] = (char*)str;
+ argv[1] = NULL;
+ list = expand_variables(argv, 0x80); /* 0x80: make one-element expansion */
+ /* To be removed / made conditional later. */
+ if (!list[0] || list[1])
+ bb_error_msg_and_die("BUG in varexp");
+ /* actually, just move string 2*sizeof(char*) bytes back */
+ strcpy((char*)list, list[0]);
+ return (char*)list;
}
-
/* This is used to get/check local shell variables */
static const char *get_local_var(const char *s)
{
@@ -3195,7 +3147,7 @@
int len = 0;
for (n = 0; inp[n]; n++) {
- p = insert_var_value(inp[n]);
+ p = expand_variables_to_string(inp[n]);
val_len = strlen(p);
str = xrealloc(str, len + val_len + 3); /* +3: space, '\n', <nul>*/
str[len++] = ' ';
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