redefined stack manipulation functions as macros
Tibor Bizjak
parent
1f31d9e372
commit
919eb0c413
|
|
@ -3,13 +3,14 @@
|
|||
#include <string.h>
|
||||
#include <math.h>
|
||||
|
||||
|
||||
/* --------- ERROR MESSAGES */
|
||||
#define printerr(format, ...) printf("error: " format "\n", ##__VA_ARGS__)
|
||||
int stack_len(void);
|
||||
void push(double x);
|
||||
double pop(void);
|
||||
double peek(void);
|
||||
void clear(void);
|
||||
#define ZERODIV_ERR "zero divisor"
|
||||
#define DOMAIN_ERR "operand not in domain [%d, %d]"
|
||||
#define NEG_ERR "negative operand %g"
|
||||
#define FULL_STACK_ERR "stack full, can't push %g"
|
||||
#define EMPTY_STACK_ERR "stack empty"
|
||||
#define SHORT_STACK_ERR "not enough elements on stack"
|
||||
|
||||
/* --------- PROMPT FORMATS */
|
||||
#define PROMPT_F ">> "
|
||||
|
|
@ -17,52 +18,72 @@ void clear(void);
|
|||
#define PEEK_PRINT_F "peek -> %.8g\n"
|
||||
#define EMPTY_F "empty\n"
|
||||
|
||||
/* --------- ERROR MESSAGES */
|
||||
#define ZERODIV_ERR "zero divisor"
|
||||
#define DOMAIN_ERR "operand not in domain [%d, %d]"
|
||||
#define NEG_ERR "negative operand %g"
|
||||
#define FULL_STACK_ERR "stack full, can't push %g"
|
||||
#define EMPTY_STACK_ERR "stack empty"
|
||||
/* ------ GLOBAL VALUE STACK */
|
||||
#define MAXVAL 100 /* maximum depth of val stack */
|
||||
|
||||
int sp = 0;
|
||||
double val[MAXVAL];
|
||||
|
||||
#define length() sp
|
||||
/* push: push f onto value stack */
|
||||
#define push(x) ((sp < MAXVAL) ? val[sp++] = (x) : printerr(FULL_STACK_ERR, ((double) (x))))
|
||||
/* pop: pop and return top value from stack */
|
||||
#define pop() (sp ? val[--sp] : (printerr(EMPTY_STACK_ERR), 0))
|
||||
/* peek: return top value from stack, leave stack unchanged */
|
||||
#define peek() (sp ? val[sp-1] : (printerr(EMPTY_STACK_ERR), 0))
|
||||
/* clear: clear stack */
|
||||
#define clear() (sp = 0)
|
||||
/* print_peek: print top element, leave stack unchanged */
|
||||
#define print_peek() printf(PEEK_PRINT_F, peek())
|
||||
/* dup: duplicate top element */
|
||||
#define dup() push(peek())
|
||||
/* swap: swap top two elements */
|
||||
#define swap() \
|
||||
do { if (sp < 2) printerr(SHORT_STACK_ERR); else { \
|
||||
double tmp = peek(); \
|
||||
val[sp-1] = val[sp-2], val[sp-2] = tmp; \
|
||||
} \
|
||||
} while (0)
|
||||
|
||||
/* --------- CALCULATOR FUNCTION TYPES */
|
||||
/* renaming macro */
|
||||
#define CALL(TOKEN, F, APPLY, ...) APPLY(F, ##__VA_ARGS__)
|
||||
|
||||
/* the following macros allow us to call native c constructs in a declarative style */
|
||||
/* value */
|
||||
#define VALUE(ID) push(ID)
|
||||
|
||||
/* command */
|
||||
#define COMMAND(CMD) CMD()
|
||||
|
||||
/* commutative operator */
|
||||
#define COMM_OP(OP) push(pop() OP pop())
|
||||
/* non-commutative operator */
|
||||
#define NONC_OP(OP, T, ...) \
|
||||
do { T op = pop(); __VA_ARGS__ push(((T) pop()) OP op); } while (0)
|
||||
/* nonzero second operand */
|
||||
#define NONZ_SND_OP if (!op) printerr(ZERODIV_ERR); else
|
||||
|
||||
/* unary function */
|
||||
#define UNARY_FUN(F) push(F(pop()))
|
||||
/* unary function with tests */
|
||||
#define UNARY_T_FUN(F, T, ...) do { double op = pop(); __VA_ARGS__ push(F(op)); } while (0)
|
||||
/* operator in range */
|
||||
#define IN_RANGE(A, B) if (op < A || op > B) printerr(DOMAIN_ERR, A, B); else
|
||||
/* operator > 0 */
|
||||
#define NON_NEG if (op < 0) printerr(NEG_ERR, op); else
|
||||
|
||||
#define UNARY_T_FUN(F, T, ...) \
|
||||
do { double op = pop(); __VA_ARGS__ push(F(op)); } while (0)
|
||||
/* commutative function */
|
||||
#define COMM_FUN(F) push(F(pop(), pop()))
|
||||
/* non-commutative function */
|
||||
#define NONC_FUN(F, T, ...) \
|
||||
do { T op = pop(); __VA_ARGS__ push(F(pop(), op)); } while (0)
|
||||
|
||||
/* nonzero operand */
|
||||
#define NONZ_SND_OP if (!op) printerr(ZERODIV_ERR); else
|
||||
/* operator in range */
|
||||
#define IN_RANGE(A, B) if (op < A || op > B) printerr(DOMAIN_ERR, A, B); else
|
||||
/* non-negative operand */
|
||||
#define NON_NEG if (op < 0) printerr(NEG_ERR, op); else
|
||||
|
||||
|
||||
/* --------- CALCULATOR FUNCTIONS */
|
||||
|
||||
/* renaming macro */
|
||||
#define CALL(TOKEN, F, APPLY, ...) APPLY(F, ##__VA_ARGS__)
|
||||
|
||||
|
||||
#define COMMANDS \
|
||||
X(print, COMMAND) \
|
||||
X(print, CALL, print_peek, COMMAND) \
|
||||
X(dup, COMMAND) \
|
||||
X(swap, COMMAND) \
|
||||
X(clear, COMMAND)
|
||||
|
|
@ -107,12 +128,6 @@ void clear(void);
|
|||
|
||||
/* --------- COMMAND DEFINITIONS */
|
||||
|
||||
#define print() printf(PEEK_PRINT_F, peek())
|
||||
#define dup() push(peek())
|
||||
#define swap() \
|
||||
do { double fst, snd; snd = pop(), fst = pop(); push(snd), push(fst); } while (0)
|
||||
|
||||
|
||||
#define MAXTOKEN 100
|
||||
int gettoken(char *token, int max_t);
|
||||
|
||||
|
|
@ -126,7 +141,7 @@ int main()
|
|||
printf(PROMPT_F);
|
||||
while (t_len = gettoken(token, MAXTOKEN)) {
|
||||
if (t_len < 0) { /* newline token */
|
||||
if (stack_len())
|
||||
if (length())
|
||||
printf(POP_PRINT_F, pop());
|
||||
else
|
||||
printf(EMPTY_F);
|
||||
|
|
@ -140,9 +155,9 @@ int main()
|
|||
#undef X
|
||||
push(atof(token));
|
||||
}
|
||||
if (!stack_len())
|
||||
if (!length())
|
||||
putchar('\n');
|
||||
while (stack_len())
|
||||
while (length())
|
||||
printf(POP_PRINT_F, pop());
|
||||
|
||||
return 0;
|
||||
|
|
@ -176,47 +191,3 @@ int gettoken(char *token, int t_max)
|
|||
token[i] = '\0';
|
||||
return i;
|
||||
}
|
||||
|
||||
/* ------ GLOBAL STACK */
|
||||
#define MAXVAL 100 /* maximum depth of val stack */
|
||||
|
||||
int sp = 0;
|
||||
double val[MAXVAL];
|
||||
|
||||
int stack_len()
|
||||
{
|
||||
return sp;
|
||||
}
|
||||
|
||||
|
||||
/* push: push f onto value stack */
|
||||
void push(double f)
|
||||
{
|
||||
if (sp < MAXVAL)
|
||||
val[sp++] = f;
|
||||
else
|
||||
printerr(FULL_STACK_ERR, f);
|
||||
}
|
||||
|
||||
/* pop: pop and return top value from stack */
|
||||
double pop(void)
|
||||
{
|
||||
if (sp)
|
||||
return val[--sp];
|
||||
printerr(EMPTY_STACK_ERR);
|
||||
return 0;
|
||||
}
|
||||
|
||||
/* peek: return top value from stack, leave stack unchanged */
|
||||
double peek(void)
|
||||
{
|
||||
if (sp)
|
||||
return val[sp-1];
|
||||
printerr(EMPTY_STACK_ERR);
|
||||
return 0.0;
|
||||
}
|
||||
|
||||
void clear(void)
|
||||
{
|
||||
sp = 0;
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in New Issue