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-rw-r--r--gnu/usr.bin/bc/dc/stack.c489
1 files changed, 489 insertions, 0 deletions
diff --git a/gnu/usr.bin/bc/dc/stack.c b/gnu/usr.bin/bc/dc/stack.c
new file mode 100644
index 00000000000..0268b70d0ed
--- /dev/null
+++ b/gnu/usr.bin/bc/dc/stack.c
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+/*
+ * implement stack functions for dc
+ *
+ * Copyright (C) 1994, 1997, 1998 Free Software Foundation, Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, you can either send email to this
+ * program's author (see below) or write to: The Free Software Foundation,
+ * Inc.; 675 Mass Ave. Cambridge, MA 02139, USA.
+ */
+
+/* This module is the only one that knows what stacks (both the
+ * regular evaluation stack and the named register stacks)
+ * look like.
+ */
+
+#include "config.h"
+
+#include <stdio.h>
+#ifdef HAVE_STDLIB_H
+# include <stdlib.h>
+#endif
+#include "dc.h"
+#include "dc-proto.h"
+#include "dc-regdef.h"
+
+/* an oft-used error message: */
+#define Empty_Stack fprintf(stderr, "%s: stack empty\n", progname)
+
+
+/* simple linked-list implementaion suffices: */
+struct dc_list {
+ dc_data value;
+ struct dc_array *array; /* opaque */
+ struct dc_list *link;
+};
+typedef struct dc_list dc_list;
+
+/* the anonymous evaluation stack */
+static dc_list *dc_stack=NULL;
+
+/* the named register stacks */
+static dc_list *dc_register[DC_REGCOUNT];
+
+
+/* allocate a new dc_list item */
+static dc_list *
+dc_alloc DC_DECLVOID()
+{
+ dc_list *result;
+
+ result = dc_malloc(sizeof *result);
+ result->value.dc_type = DC_UNINITIALIZED;
+ result->array = NULL;
+ result->link = NULL;
+ return result;
+}
+
+
+/* check that there are two numbers on top of the stack,
+ * then call op with the popped numbers. Construct a dc_data
+ * value from the dc_num returned by op and push it
+ * on the stack.
+ * If the op call doesn't return DC_SUCCESS, then leave the stack
+ * unmodified.
+ */
+void
+dc_binop DC_DECLARG((op, kscale))
+ int (*op)DC_PROTO((dc_num, dc_num, int, dc_num *)) DC_DECLSEP
+ int kscale DC_DECLEND
+{
+ dc_data a;
+ dc_data b;
+ dc_data r;
+
+ if (!dc_stack || !dc_stack->link){
+ Empty_Stack;
+ return;
+ }
+ if (dc_stack->value.dc_type!=DC_NUMBER
+ || dc_stack->link->value.dc_type!=DC_NUMBER){
+ fprintf(stderr, "%s: non-numeric value\n", progname);
+ return;
+ }
+ (void)dc_pop(&b);
+ (void)dc_pop(&a);
+ if ((*op)(a.v.number, b.v.number, kscale, &r.v.number) == DC_SUCCESS){
+ r.dc_type = DC_NUMBER;
+ dc_push(r);
+ dc_free_num(&a.v.number);
+ dc_free_num(&b.v.number);
+ }else{
+ /* op failed; restore the stack */
+ dc_push(a);
+ dc_push(b);
+ }
+}
+
+/* check that there are two numbers on top of the stack,
+ * then call op with the popped numbers. Construct two dc_data
+ * values from the dc_num's returned by op and push them
+ * on the stack.
+ * If the op call doesn't return DC_SUCCESS, then leave the stack
+ * unmodified.
+ */
+void
+dc_binop2 DC_DECLARG((op, kscale))
+ int (*op)DC_PROTO((dc_num, dc_num, int, dc_num *, dc_num *)) DC_DECLSEP
+ int kscale DC_DECLEND
+{
+ dc_data a;
+ dc_data b;
+ dc_data r1;
+ dc_data r2;
+
+ if (!dc_stack || !dc_stack->link){
+ Empty_Stack;
+ return;
+ }
+ if (dc_stack->value.dc_type!=DC_NUMBER
+ || dc_stack->link->value.dc_type!=DC_NUMBER){
+ fprintf(stderr, "%s: non-numeric value\n", progname);
+ return;
+ }
+ (void)dc_pop(&b);
+ (void)dc_pop(&a);
+ if ((*op)(a.v.number, b.v.number, kscale,
+ &r1.v.number, &r2.v.number) == DC_SUCCESS){
+ r1.dc_type = DC_NUMBER;
+ dc_push(r1);
+ r2.dc_type = DC_NUMBER;
+ dc_push(r2);
+ dc_free_num(&a.v.number);
+ dc_free_num(&b.v.number);
+ }else{
+ /* op failed; restore the stack */
+ dc_push(a);
+ dc_push(b);
+ }
+}
+
+/* check that there are two numbers on top of the stack,
+ * then call dc_compare with the popped numbers.
+ * Return negative, zero, or positive based on the ordering
+ * of the two numbers.
+ */
+int
+dc_cmpop DC_DECLVOID()
+{
+ int result;
+ dc_data a;
+ dc_data b;
+
+ if (!dc_stack || !dc_stack->link){
+ Empty_Stack;
+ return 0;
+ }
+ if (dc_stack->value.dc_type!=DC_NUMBER
+ || dc_stack->link->value.dc_type!=DC_NUMBER){
+ fprintf(stderr, "%s: non-numeric value\n", progname);
+ return 0;
+ }
+ (void)dc_pop(&b);
+ (void)dc_pop(&a);
+ result = dc_compare(b.v.number, a.v.number);
+ dc_free_num(&a.v.number);
+ dc_free_num(&b.v.number);
+ return result;
+}
+
+/* check that there are three numbers on top of the stack,
+ * then call op with the popped numbers. Construct a dc_data
+ * value from the dc_num returned by op and push it
+ * on the stack.
+ * If the op call doesn't return DC_SUCCESS, then leave the stack
+ * unmodified.
+ */
+void
+dc_triop DC_DECLARG((op, kscale))
+ int (*op)DC_PROTO((dc_num, dc_num, dc_num, int, dc_num *)) DC_DECLSEP
+ int kscale DC_DECLEND
+{
+ dc_data a;
+ dc_data b;
+ dc_data c;
+ dc_data r;
+
+ if (!dc_stack || !dc_stack->link || !dc_stack->link->link){
+ Empty_Stack;
+ return;
+ }
+ if (dc_stack->value.dc_type!=DC_NUMBER
+ || dc_stack->link->value.dc_type!=DC_NUMBER
+ || dc_stack->link->link->value.dc_type!=DC_NUMBER){
+ fprintf(stderr, "%s: non-numeric value\n", progname);
+ return;
+ }
+ (void)dc_pop(&c);
+ (void)dc_pop(&b);
+ (void)dc_pop(&a);
+ if ((*op)(a.v.number, b.v.number, c.v.number,
+ kscale, &r.v.number) == DC_SUCCESS){
+ r.dc_type = DC_NUMBER;
+ dc_push(r);
+ dc_free_num(&a.v.number);
+ dc_free_num(&b.v.number);
+ dc_free_num(&c.v.number);
+ }else{
+ /* op failed; restore the stack */
+ dc_push(a);
+ dc_push(b);
+ dc_push(c);
+ }
+}
+
+
+/* initialize the register stacks to their initial values */
+void
+dc_register_init DC_DECLVOID()
+{
+ int i;
+
+ for (i=0; i<DC_REGCOUNT; ++i)
+ dc_register[i] = NULL;
+}
+
+/* clear the evaluation stack */
+void
+dc_clear_stack DC_DECLVOID()
+{
+ dc_list *n;
+ dc_list *t;
+
+ for (n=dc_stack; n; n=t){
+ t = n->link;
+ if (n->value.dc_type == DC_NUMBER)
+ dc_free_num(&n->value.v.number);
+ else if (n->value.dc_type == DC_STRING)
+ dc_free_str(&n->value.v.string);
+ else
+ dc_garbage("in stack", -1);
+ dc_array_free(n->array);
+ free(n);
+ }
+ dc_stack = NULL;
+}
+
+/* push a value onto the evaluation stack */
+void
+dc_push DC_DECLARG((value))
+ dc_data value DC_DECLEND
+{
+ dc_list *n = dc_alloc();
+
+ if (value.dc_type!=DC_NUMBER && value.dc_type!=DC_STRING)
+ dc_garbage("in data being pushed", -1);
+ n->value = value;
+ n->link = dc_stack;
+ dc_stack = n;
+}
+
+/* push a value onto the named register stack */
+void
+dc_register_push DC_DECLARG((stackid, value))
+ int stackid DC_DECLSEP
+ dc_data value DC_DECLEND
+{
+ dc_list *n = dc_alloc();
+
+ stackid = regmap(stackid);
+ n->value = value;
+ n->link = dc_register[stackid];
+ dc_register[stackid] = n;
+}
+
+/* set *result to the value on the top of the evaluation stack */
+/* The caller is responsible for duplicating the value if it
+ * is to be maintained as anything more than a transient identity.
+ *
+ * DC_FAIL is returned if the stack is empty (and *result unchanged),
+ * DC_SUCCESS is returned otherwise
+ */
+int
+dc_top_of_stack DC_DECLARG((result))
+ dc_data *result DC_DECLEND
+{
+ if (!dc_stack){
+ Empty_Stack;
+ return DC_FAIL;
+ }
+ if (dc_stack->value.dc_type!=DC_NUMBER
+ && dc_stack->value.dc_type!=DC_STRING)
+ dc_garbage("at top of stack", -1);
+ *result = dc_stack->value;
+ return DC_SUCCESS;
+}
+
+/* set *result to a dup of the value on the top of the named register stack */
+/*
+ * DC_FAIL is returned if the named stack is empty (and *result unchanged),
+ * DC_SUCCESS is returned otherwise
+ */
+int
+dc_register_get DC_DECLARG((regid, result))
+ int regid DC_DECLSEP
+ dc_data *result DC_DECLEND
+{
+ dc_list *r;
+
+ regid = regmap(regid);
+ r = dc_register[regid];
+ if ( ! r ){
+ fprintf(stderr, "%s: register ", progname);
+ dc_show_id(stderr, regid, " is empty\n");
+ return DC_FAIL;
+ }
+ *result = dc_dup(r->value);
+ return DC_SUCCESS;
+}
+
+/* set the top of the named register stack to the indicated value */
+/* If the named stack is empty, craft a stack entry to enter the
+ * value into.
+ */
+void
+dc_register_set DC_DECLARG((regid, value))
+ int regid DC_DECLSEP
+ dc_data value DC_DECLEND
+{
+ dc_list *r;
+
+ regid = regmap(regid);
+ r = dc_register[regid];
+ if ( ! r )
+ dc_register[regid] = dc_alloc();
+ else if (r->value.dc_type == DC_NUMBER)
+ dc_free_num(&r->value.v.number);
+ else if (r->value.dc_type == DC_STRING)
+ dc_free_str(&r->value.v.string);
+ else
+ dc_garbage("", regid);
+ dc_register[regid]->value = value;
+}
+
+/* pop from the evaluation stack
+ *
+ * DC_FAIL is returned if the stack is empty (and *result unchanged),
+ * DC_SUCCESS is returned otherwise
+ */
+int
+dc_pop DC_DECLARG((result))
+ dc_data *result DC_DECLEND
+{
+ dc_list *r;
+
+ r = dc_stack;
+ if (!r){
+ Empty_Stack;
+ return DC_FAIL;
+ }
+ if (r->value.dc_type!=DC_NUMBER && r->value.dc_type!=DC_STRING)
+ dc_garbage("at top of stack", -1);
+ *result = r->value;
+ dc_stack = r->link;
+ dc_array_free(r->array);
+ free(r);
+ return DC_SUCCESS;
+}
+
+/* pop from the named register stack
+ *
+ * DC_FAIL is returned if the named stack is empty (and *result unchanged),
+ * DC_SUCCESS is returned otherwise
+ */
+int
+dc_register_pop DC_DECLARG((stackid, result))
+ int stackid DC_DECLSEP
+ dc_data *result DC_DECLEND
+{
+ dc_list *r;
+
+ stackid = regmap(stackid);
+ r = dc_register[stackid];
+ if (!r){
+ fprintf(stderr, "%s: stack register ", progname);
+ dc_show_id(stderr, stackid, " is empty\n");
+ return DC_FAIL;
+ }
+ if (r->value.dc_type!=DC_NUMBER && r->value.dc_type!=DC_STRING)
+ dc_garbage(" stack", stackid);
+ *result = r->value;
+ dc_register[stackid] = r->link;
+ dc_array_free(r->array);
+ free(r);
+ return DC_SUCCESS;
+}
+
+
+/* tell how many entries are currently on the evaluation stack */
+int
+dc_tell_stackdepth DC_DECLVOID()
+{
+ dc_list *n;
+ int depth=0;
+
+ for (n=dc_stack; n; n=n->link)
+ ++depth;
+ return depth;
+}
+
+
+/* return the length of the indicated data value;
+ * if discard_p is DC_TOSS, the deallocate the value when done
+ *
+ * The definition of a datum's length is deligated to the
+ * appropriate module.
+ */
+int
+dc_tell_length DC_DECLARG((value, discard_p))
+ dc_data value DC_DECLSEP
+ dc_discard discard_p DC_DECLEND
+{
+ int length;
+
+ if (value.dc_type == DC_NUMBER){
+ length = dc_numlen(value.v.number);
+ if (discard_p == DC_TOSS)
+ dc_free_num(&value.v.number);
+ } else if (value.dc_type == DC_STRING) {
+ length = dc_strlen(value.v.string);
+ if (discard_p == DC_TOSS)
+ dc_free_str(&value.v.string);
+ } else {
+ dc_garbage("in tell_length", -1);
+ /*NOTREACHED*/
+ length = 0; /*just to suppress spurious compiler warnings*/
+ }
+ return length;
+}
+
+
+
+/* print out all of the values on the evaluation stack */
+void
+dc_printall DC_DECLARG((obase))
+ int obase DC_DECLEND
+{
+ dc_list *n;
+
+ for (n=dc_stack; n; n=n->link)
+ dc_print(n->value, obase, DC_WITHNL, DC_KEEP);
+}
+
+
+
+
+/* get the current array head for the named array */
+struct dc_array *
+dc_get_stacked_array DC_DECLARG((array_id))
+ int array_id DC_DECLEND
+{
+ dc_list *r = dc_register[regmap(array_id)];
+ return r ? r->array : NULL;
+}
+
+/* set the current array head for the named array */
+void
+dc_set_stacked_array DC_DECLARG((array_id, new_head))
+ int array_id DC_DECLSEP
+ struct dc_array *new_head DC_DECLEND
+{
+ dc_list *r;
+
+ array_id = regmap(array_id);
+ r = dc_register[array_id];
+ if ( ! r )
+ r = dc_register[array_id] = dc_alloc();
+ r->array = new_head;
+}
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