hush: consolidated variable expansion for assignments and "normal" one.

-435 bytes. Tested against testsuite.

diff --git a/shell/hush.c b/shell/hush.c
index 0a035ca..9f0cc64 100644 (file)
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -444,8 +444,9 @@ static void delete_finished_bg_job(struct pipe *pi);
 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 @@ static void pseudo_exec_argv(char **argv)
                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 @@ static void pseudo_exec_argv(char **argv)
                _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 @@ static int run_pipe_real(struct pipe *pi)
                                        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 @@ static int run_pipe_real(struct pipe *pi)
                        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 @@ static int run_pipe_real(struct pipe *pi)
                                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 @@ static int run_pipe_real(struct pipe *pi)
                                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 @@ static int run_list_real(struct pipe *pi)
                                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 @@ static int xglob(o_string *dest, int flags, glob_t *pglob)
        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 $VAR).
@@ -2371,8 +2371,11 @@ static int expand_on_ifs(char **list, int n, char **posp, const char *str)
  * 'echo -$*-'. 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 @@ static int expand_vars_to_list(char **list, int n, char **posp, char *arg)
                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 @@ static int expand_vars_to_list(char **list, int n, char **posp, char *arg)
                                                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 @@ static int expand_vars_to_list(char **list, int n, char **posp, char *arg)
        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 @@ static char **do_variable_expansion(char **argv)
        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 @@ static char **do_variable_expansion(char **argv)
        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;
-
-       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);
-               }
+       char *argv[2], **list;
 
-               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 @@ static char* make_string(char **inp)
        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++] = ' ';