Changeset 2725 in MondoRescue for branches/2.2.9/mindi-busybox/miscutils/dc.c

Timestamp:

Feb 25, 2011, 9:26:54 PM (13 years ago)

Author:

Bruno Cornec

Message:

• Update mindi-busybox to 1.18.3 to avoid problems with the tar command which is now failing on recent versions with busybox 1.7.3

File:

• branches/2.2.9/mindi-busybox/miscutils/dc.c (modified) (11 diffs)

branches/2.2.9/mindi-busybox/miscutils/dc.c

@@ -1 +1 @@
 /* vi: set sw=4 ts=4: */
 /*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
@@ -7 +7 @@
 #include <math.h>
 
-/* Tiny RPN calculator, because "expr" didn't give me bitwise operations. */
-
-enum { STACK_SIZE = COMMON_BUFSIZE / sizeof(double) };
-
-#define stack ((double*)&bb_common_bufsiz1)
-static unsigned int pointer;
-static unsigned char base;
+//usage:#define dc_trivial_usage
+//usage:       "EXPRESSION..."
+//usage:
+//usage:#define dc_full_usage "\n\n"
+//usage:       "Tiny RPN calculator. Operations:\n"
+//usage:       "+, add, -, sub, *, mul, /, div, %, mod, **, exp, and, or, not, eor,\n"
+//usage:       "p - print top of the stack (without popping),\n"
+//usage:       "f - print entire stack,\n"
+//usage:       "o - pop the value and set output radix (must be 10, 16, 8 or 2).\n"
+//usage:       "Examples: 'dc 2 2 add' -> 4, 'dc 8 8 * 2 2 + /' -> 16"
+//usage:
+//usage:#define dc_example_usage
+//usage:       "$ dc 2 2 + p\n"
+//usage:       "4\n"
+//usage:       "$ dc 8 8 \\* 2 2 + / p\n"
+//usage:       "16\n"
+//usage:       "$ dc 0 1 and p\n"
+//usage:       "0\n"
+//usage:       "$ dc 0 1 or p\n"
+//usage:       "1\n"
+//usage:       "$ echo 72 9 div 8 mul p | dc\n"
+//usage:       "64\n"
+
+#if 0
+typedef unsigned data_t;
+#define DATA_FMT ""
+#elif 0
+typedef unsigned long data_t;
+#define DATA_FMT "l"
+#else
+typedef unsigned long long data_t;
+#define DATA_FMT "ll"
+#endif
+
+
+struct globals {
+    unsigned pointer;
+    unsigned base;
+    double stack[1];
+} FIX_ALIASING;
+enum { STACK_SIZE = (COMMON_BUFSIZE - offsetof(struct globals, stack)) / sizeof(double) };
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define pointer   (G.pointer   )
+#define base      (G.base      )
+#define stack     (G.stack     )
+#define INIT_G() do { \
+    base = 10; \
+} while (0)
+
 
 static void push(double a)
@@ -46 +88 @@
 }
 
+#if ENABLE_FEATURE_DC_LIBM
 static void power(void)
 {
@@ -52 +95 @@
     push(pow(pop(), topower));
 }
+#endif
 
 static void divide(void)
@@ -62 +106 @@
 static void mod(void)
 {
-    unsigned int d = pop();
-
-    push((unsigned int) pop() % d);
+    data_t d = pop();
+
+    push((data_t) pop() % d);
 }
 
 static void and(void)
 {
-    push((unsigned int) pop() & (unsigned int) pop());
+    push((data_t) pop() & (data_t) pop());
 }
 
 static void or(void)
 {
-    push((unsigned int) pop() | (unsigned int) pop());
+    push((data_t) pop() | (data_t) pop());
 }
 
 static void eor(void)
 {
-    push((unsigned int) pop() ^ (unsigned int) pop());
+    push((data_t) pop() ^ (data_t) pop());
 }
 
 static void not(void)
 {
-    push(~(unsigned int) pop());
+    push(~(data_t) pop());
 }
 
 static void set_output_base(void)
 {
-    base = (unsigned char)pop();
-    if ((base != 10) && (base != 16)) {
-        bb_error_msg("error, base %d is not supported", base);
+    static const char bases[] ALIGN1 = { 2, 8, 10, 16, 0 };
+    unsigned b = (unsigned)pop();
+
+    base = *strchrnul(bases, b);
+    if (base == 0) {
+        bb_error_msg("error, base %u is not supported", b);
         base = 10;
     }
@@ -98 +145 @@
 static void print_base(double print)
 {
-    if (base == 16)
-        printf("%x\n", (unsigned int)print);
-    else
-        printf("%g\n", print);
+    data_t x, i;
+
+    x = (data_t) print;
+    if (base == 10) {
+        if (x == print) /* exactly representable as unsigned integer */
+            printf("%"DATA_FMT"u\n", x);
+        else
+            printf("%g\n", print);
+        return;
+    }
+
+    switch (base) {
+    case 16:
+        printf("%"DATA_FMT"x\n", x);
+        break;
+    case 8:
+        printf("%"DATA_FMT"o\n", x);
+        break;
+    default: /* base 2 */
+        i = MAXINT(data_t) - (MAXINT(data_t) >> 1);
+        /* i is 100000...00000 */
+        do {
+            if (x & i)
+                break;
+            i >>= 1;
+        } while (i > 1);
+        do {
+            bb_putchar('1' - !(x & i));
+            i >>= 1;
+        } while (i);
+        bb_putchar('\n');
+    }
 }
 
 static void print_stack_no_pop(void)
 {
-    unsigned int i = pointer;
+    unsigned i = pointer;
     while (i)
         print_base(stack[--i]);
@@ -130 +205 @@
     {"/",   divide},
     {"div", divide},
+#if ENABLE_FEATURE_DC_LIBM
     {"**",  power},
     {"exp", power},
     {"pow", power},
+#endif
     {"%",   mod},
     {"mod", mod},
@@ -143 +220 @@
     {"f", print_stack_no_pop},
     {"o", set_output_base},
-    {"", 0}
+    { "", NULL }
 };
 
 static void stack_machine(const char *argument)
 {
-    char *endPointer = 0;
+    char *endPointer;
     double d;
     const struct op *o = operators;
 
-    if (argument == 0)
-        return;
-
     d = strtod(argument, &endPointer);
 
-    if (endPointer != argument) {
+    if (endPointer != argument && *endPointer == '\0') {
         push(d);
         return;
     }
 
-    while (o->name[0]) {
+    while (o->function) {
         if (strcmp(o->name, argument) == 0) {
             o->function();
@@ -169 +243 @@
         o++;
     }
-    bb_error_msg_and_die("%s: syntax error", argument);
+    bb_error_msg_and_die("syntax error at '%s'", argument);
 }
 
@@ -177 +251 @@
 static char *get_token(char **buffer)
 {
-    char *start = NULL;
-    char *current;
-
-    current = skip_whitespace(*buffer);
-    if (*current != 0) {
-        start = current;
-        current = skip_non_whitespace(current);
-        *buffer = current;
-    }
-    return start;
-}
-
-/* In Perl one might say, scalar m|\s*(\S+)\s*|g */
-static int number_of_tokens(char *buffer)
-{
-    int   i = 0;
-    char *b = buffer;
-    while (get_token(&b)) { i++; }
-    return i;
-}
-
-int dc_main(int argc, char **argv);
-int dc_main(int argc, char **argv)
-{
-    /* take stuff from stdin if no args are given */
-    if (argc <= 1) {
-        int i, len;
-        char *line   = NULL;
-        char *cursor = NULL;
-        char *token  = NULL;
-        while ((line = xmalloc_getline(stdin))) {
+    char *current = skip_whitespace(*buffer);
+    if (*current != '\0') {
+        *buffer = skip_non_whitespace(current);
+        return current;
+    }
+    return NULL;
+}
+
+int dc_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
+int dc_main(int argc UNUSED_PARAM, char **argv)
+{
+    INIT_G();
+
+    argv++;
+    if (!argv[0]) {
+        /* take stuff from stdin if no args are given */
+        char *line;
+        char *cursor;
+        char *token;
+        while ((line = xmalloc_fgetline(stdin)) != NULL) {
             cursor = line;
-            len = number_of_tokens(line);
-            for (i = 0; i < len; i++) {
+            while (1) {
                 token = get_token(&cursor);
-                *cursor++ = 0;
+                if (!token)
+                    break;
+                *cursor++ = '\0';
                 stack_machine(token);
             }
@@ -218 +282 @@
         }
     } else {
-        if (*argv[1] == '-')
-            bb_show_usage();
-        while (argc >= 2) {
-            stack_machine(argv[1]);
-            argv++;
-            argc--;
-        }
+        // why? it breaks "dc -2 2 * p"
+        //if (argv[0][0] == '-')
+        //  bb_show_usage();
+        do {
+            stack_machine(*argv);
+        } while (*++argv);
     }
     return EXIT_SUCCESS;