split math code out of ash and into a standalone library so we can use it in any shell (like hush!)

1 files changed, 91 insertions, 11 deletions

diff --git a/shell/hush.c b/shell/hush.c
index af6763517..e93e5a9a0 100644
--- a/shell/hush.c
+++ b/shell/hush.c
@@ -76,6 +76,8 @@
 #include <fnmatch.h>
 #endif
 
+#include "math.h"
+
 #define HUSH_VER_STR "0.92"
 
 #if defined SINGLE_APPLET_MAIN
@@ -452,6 +454,9 @@ struct globals {
 #if ENABLE_FEATURE_EDITING
         line_input_t *line_input_state;
 #endif
+#if ENABLE_SH_MATH_SUPPORT
+        arith_eval_hooks_t hooks;
+#endif
         pid_t root_pid;
         pid_t last_bg_pid;
 #if ENABLE_HUSH_JOB
@@ -1164,6 +1169,31 @@ static int unset_local_var(const char *name)
         return EXIT_SUCCESS;
 }
 
+#if ENABLE_SH_MATH_SUPPORT
+#define is_name(c)      ((c) == '_' || isalpha((unsigned char)(c)))
+#define is_in_name(c)   ((c) == '_' || isalnum((unsigned char)(c)))
+static char *endofname(const char *name)
+{
+        char *p;
+
+        p = (char *) name;
+        if (!is_name(*p))
+                return p;
+        while (*++p) {
+                if (!is_in_name(*p))
+                        break;
+        }
+        return p;
+}
+
+static void arith_set_local_var(const char *name, const char *val, int flags)
+{
+        /* arith code doesnt malloc space, so do it for it */
+        char *var = xmalloc(strlen(name) + 1 + strlen(val) + 1);
+        sprintf(var, "%s=%s", name, val);
+        set_local_var(var, flags);
+}
+#endif
 
 /*
  * in_str support
@@ -1374,6 +1404,11 @@ static void o_addstr(o_string *o, const char *str, int len)
         o->data[o->length] = '\0';
 }
 
+static void o_addstrauto(o_string *o, const char *str)
+{
+        o_addstr(o, str, strlen(str) + 1);
+}
+
 static void o_addstr_duplicate_backslash(o_string *o, const char *str, int len)
 {
         while (len) {
@@ -1564,7 +1599,7 @@ static int o_glob(o_string *o, int n)
                 char **argv = globdata.gl_pathv;
                 o->length = pattern - o->data; /* "forget" pattern */
                 while (1) {
-                        o_addstr(o, *argv, strlen(*argv) + 1);
+                        o_addstrauto(o, *argv);
                         n = o_save_ptr_helper(o, n);
                         argv++;
                         if (!*argv)
@@ -1770,6 +1805,28 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                         goto store_val;
                 }
 #endif
+#if ENABLE_SH_MATH_SUPPORT
+                case '+': { /* <SPECIAL_VAR_SYMBOL>(cmd<SPECIAL_VAR_SYMBOL> */
+                        arith_t res;
+                        char buf[30];
+                        int errcode;
+                        *p = '\0';
+                        ++arg;
+                        debug_printf_subst("ARITH '%s' first_ch %x\n", arg, first_ch);
+                        res = arith(arg, &errcode, &G.hooks);
+                        if (errcode < 0)
+                                switch (errcode) {
+                                case -3: maybe_die("arith", "exponent less than 0"); break;
+                                case -2: maybe_die("arith", "divide by zero"); break;
+                                case -5: maybe_die("arith", "expression recursion loop detected"); break;
+                                default: maybe_die("arith", "syntax error");
+                                }
+                        sprintf(buf, arith_t_fmt, res);
+                        o_addstrauto(output, buf);
+                        debug_printf_subst("ARITH RES '"arith_t_fmt"'\n", res);
+                        break;
+                }
+#endif
                 default: /* <SPECIAL_VAR_SYMBOL>varname<SPECIAL_VAR_SYMBOL> */
                 case_default: {
                         bool exp_len = false, exp_null = false;
@@ -1877,7 +1934,7 @@ static int expand_vars_to_list(o_string *output, int n, char *arg, char or_mask)
                 debug_print_list("expand_vars_to_list[a]", output, n);
                 /* this part is literal, and it was already pre-quoted
                  * if needed (much earlier), do not use o_addQstr here! */
-                o_addstr(output, arg, strlen(arg) + 1);
+                o_addstrauto(output, arg);
                 debug_print_list("expand_vars_to_list[b]", output, n);
         } else if (output->length == o_get_last_ptr(output, n) /* expansion is empty */
          && !(ored_ch & 0x80) /* and all vars were not quoted. */
@@ -3754,7 +3811,7 @@ static int parse_group(o_string *dest, struct parse_context *ctx,
         /* command remains "open", available for possible redirects */
 }
 
-#if ENABLE_HUSH_TICK
+#if ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT
 /* Subroutines for copying $(...) and `...` things */
 static void add_till_backquote(o_string *dest, struct in_str *input);
 /* '...' */
@@ -3834,7 +3891,7 @@ static void add_till_backquote(o_string *dest, struct in_str *input)
  * echo $(echo 'TEST)' BEST)            TEST) BEST
  * echo $(echo \(\(TEST\) BEST)         ((TEST) BEST
  */
-static void add_till_closing_curly_brace(o_string *dest, struct in_str *input)
+static void add_till_closing_paren(o_string *dest, struct in_str *input, bool dbl)
 {
         int count = 0;
         while (1) {
@@ -3844,8 +3901,14 @@ static void add_till_closing_curly_brace(o_string *dest, struct in_str *input)
                 if (ch == '(')
                         count++;
                 if (ch == ')')
-                        if (--count < 0)
-                                break;
+                        if (--count < 0) {
+                                if (!dbl)
+                                        break;
+                                if (i_peek(input) == ')') {
+                                        i_getch(input);
+                                        break;
+                                }
+                        }
                 o_addchr(dest, ch);
                 if (ch == '\'') {
                         add_till_single_quote(dest, input);
@@ -3866,7 +3929,7 @@ static void add_till_closing_curly_brace(o_string *dest, struct in_str *input)
                 }
         }
 }
-#endif /* ENABLE_HUSH_TICK */
+#endif /* ENABLE_HUSH_TICK || ENABLE_SH_MATH_SUPPORT */
 
 /* Return code: 0 for OK, 1 for syntax error */
 static int handle_dollar(o_string *dest, struct in_str *input)
@@ -3983,18 +4046,30 @@ static int handle_dollar(o_string *dest, struct in_str *input)
                         o_addchr(dest, SPECIAL_VAR_SYMBOL);
                         break;
                 }
-#if ENABLE_HUSH_TICK
                 case '(': {
-                        //int pos = dest->length;
                         i_getch(input);
+
+#if ENABLE_SH_MATH_SUPPORT
+                        if (i_peek(input) == '(') {
+                                i_getch(input);
+                                o_addchr(dest, SPECIAL_VAR_SYMBOL);
+                                o_addchr(dest, quote_mask | '+');
+                                add_till_closing_paren(dest, input, true);
+                                o_addchr(dest, SPECIAL_VAR_SYMBOL);
+                                break;
+                        }
+#endif
+
+#if ENABLE_HUSH_TICK
+                        //int pos = dest->length;
                         o_addchr(dest, SPECIAL_VAR_SYMBOL);
                         o_addchr(dest, quote_mask | '`');
-                        add_till_closing_curly_brace(dest, input);
+                        add_till_closing_paren(dest, input, false);
                         //debug_printf_subst("SUBST RES2 '%s'\n", dest->data + pos);
                         o_addchr(dest, SPECIAL_VAR_SYMBOL);
+#endif
                         break;
                 }
-#endif
                 case '_':
                         i_getch(input);
                         ch = i_peek(input);
@@ -4526,6 +4601,11 @@ int hush_main(int argc, char **argv)
 #if ENABLE_FEATURE_EDITING
         G.line_input_state = new_line_input_t(FOR_SHELL);
 #endif
+#if ENABLE_SH_MATH_SUPPORT
+        G.hooks.lookupvar = lookup_param;
+        G.hooks.setvar = arith_set_local_var;
+        G.hooks.endofname = endofname;
+#endif
         /* XXX what should these be while sourcing /etc/profile? */
         G.global_argc = argc;
         G.global_argv = argv;