Initial source

1 files changed, 391 insertions, 0 deletions

diff --git a/ddb/db_expr.c b/ddb/db_expr.c
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--- /dev/null
+++ b/ddb/db_expr.c
@@ -0,0 +1,391 @@
+/* 
+ * Mach Operating System
+ * Copyright (c) 1991,1990 Carnegie Mellon University
+ * All Rights Reserved.
+ * 
+ * Permission to use, copy, modify and distribute this software and its
+ * documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ * 
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
+ * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ * 
+ * Carnegie Mellon requests users of this software to return to
+ * 
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ * 
+ * any improvements or extensions that they make and grant Carnegie Mellon
+ * the rights to redistribute these changes.
+ */
+/*
+ *	Author: David B. Golub, Carnegie Mellon University
+ *	Date:	7/90
+ */
+#include "mach_kdb.h"
+#if MACH_KDB
+
+#include <mach/boolean.h>
+#include <machine/db_machdep.h>
+#include <ddb/db_lex.h>
+#include <ddb/db_access.h>
+#include <ddb/db_command.h>
+#include <kern/task.h>
+
+
+boolean_t
+db_term(valuep)
+	db_expr_t *valuep;
+{
+	int	t;
+
+	switch(t = db_read_token()) {
+	case tIDENT:
+	    if (!db_value_of_name(db_tok_string, valuep)) {
+		db_printf("Symbol \"%s\" not found\n", db_tok_string);
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    return (TRUE);
+	case tNUMBER:
+	    *valuep = db_tok_number;
+	    return (TRUE);
+	case tDOT:
+	    *valuep = (db_expr_t)db_dot;
+	    return (TRUE);
+	case tDOTDOT:
+	    *valuep = (db_expr_t)db_prev;
+	    return (TRUE);
+	case tPLUS:
+	    *valuep = (db_expr_t) db_next;
+	    return (TRUE);
+	case tQUOTE:
+	    *valuep = (db_expr_t)db_last_addr;
+	    return (TRUE);
+	case tDOLLAR:
+	    if (!db_get_variable(valuep))
+		return (FALSE);
+	    return (TRUE);
+	case tLPAREN:
+	    if (!db_expression(valuep)) {
+		db_error("Unmached ()s\n");
+		/*NOTREACHED*/
+	    }
+	    t = db_read_token();
+	    if (t != tRPAREN) {
+		db_printf("')' expected at \"%s...\"\n", db_tok_string);
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    return (TRUE);
+	default:
+	    db_unread_token(t);
+	    return (FALSE);
+	}
+}
+
+int
+db_size_option(modif, u_option, t_option)
+	char *modif;
+	boolean_t *u_option;
+	boolean_t *t_option;
+{
+	register  char *p;
+	int	  size = sizeof(int);
+
+	*u_option = FALSE;
+	*t_option = FALSE;
+	for (p = modif; *p; p++) {
+	    switch(*p) {
+	    case 'b':
+		size = sizeof(char);
+		break;
+	    case 'h':
+		size = sizeof(short);
+		break;
+	    case 'l':
+		size = sizeof(long);
+		break;
+	    case 'u':
+		*u_option = TRUE;
+		break;
+	    case 't':
+		*t_option = TRUE;
+		break;
+	    }
+	}
+	return(size);
+}
+
+boolean_t
+db_unary(valuep)
+	db_expr_t *valuep;
+{
+	int	  t;
+	int	  size;
+	boolean_t u_opt, t_opt;
+	task_t	  task;
+	extern	  task_t db_default_task;
+
+	t = db_read_token();
+	if (t == tMINUS) {
+	    if (!db_unary(valuep)) {
+		db_error("Expression syntax error after '-'\n");
+		/*NOTREACHED*/
+	    }
+	    *valuep = -*valuep;
+	    return (TRUE);
+	}
+	if (t == tSTAR) {
+	    /* indirection */
+	    if (!db_unary(valuep)) {
+		db_error("Expression syntax error after '*'\n");
+		/*NOTREACHED*/
+	    }
+	    task = TASK_NULL;
+	    size = sizeof(db_addr_t);
+	    u_opt = FALSE;
+	    t = db_read_token();
+	    if (t == tIDENT && db_tok_string[0] == ':') {
+		size = db_size_option(&db_tok_string[1], &u_opt, &t_opt);
+		if (t_opt)
+		    task = db_default_task;
+	    } else
+		db_unread_token(t);
+	    *valuep = db_get_task_value((db_addr_t)*valuep, size, !u_opt, task);
+	    return (TRUE);
+	}
+	if (t == tEXCL) {
+	    if (!db_unary(valuep)) {
+		db_error("Expression syntax error after '!'\n");
+		/*NOTREACHED*/
+	    }
+	    *valuep = (!(*valuep));
+	    return (TRUE);
+	}
+	db_unread_token(t);
+	return (db_term(valuep));
+}
+
+boolean_t
+db_mult_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+	char		c;
+
+	if (!db_unary(&lhs))
+	    return (FALSE);
+
+	t = db_read_token();
+	while (t == tSTAR || t == tSLASH || t == tPCT || t == tHASH
+		|| t == tBIT_AND) {
+	    c = db_tok_string[0];
+	    if (!db_term(&rhs)) {
+		db_printf("Expression syntax error after '%c'\n", c);
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    switch(t) {
+	    case tSTAR:
+		lhs *= rhs;
+		break;
+	    case tBIT_AND:
+		lhs &= rhs;
+		break;
+	    default:
+		if (rhs == 0) {
+		    db_error("Divide by 0\n");
+		    /*NOTREACHED*/
+		}
+		if (t == tSLASH)
+		    lhs /= rhs;
+		else if (t == tPCT)
+		    lhs %= rhs;
+		else
+		    lhs = ((lhs+rhs-1)/rhs)*rhs;
+	    }
+	    t = db_read_token();
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+boolean_t
+db_add_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+	char		c;
+
+	if (!db_mult_expr(&lhs))
+	    return (FALSE);
+
+	t = db_read_token();
+	while (t == tPLUS || t == tMINUS || t == tBIT_OR) {
+	    c = db_tok_string[0];
+	    if (!db_mult_expr(&rhs)) {
+		db_printf("Expression syntax error after '%c'\n", c);
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    if (t == tPLUS)
+		lhs += rhs;
+	    else if (t == tMINUS)
+		lhs -= rhs;
+	    else
+		lhs |= rhs;
+	    t = db_read_token();
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+boolean_t
+db_shift_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+
+	if (!db_add_expr(&lhs))
+	    return (FALSE);
+
+	t = db_read_token();
+	while (t == tSHIFT_L || t == tSHIFT_R) {
+	    if (!db_add_expr(&rhs)) {
+		db_printf("Expression syntax error after \"%s\"\n",
+			(t == tSHIFT_L)? "<<": ">>");
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    if (rhs < 0) {
+		db_error("Negative shift amount\n");
+		/*NOTREACHED*/
+	    }
+	    if (t == tSHIFT_L)
+		lhs <<= rhs;
+	    else {
+		/* Shift right is unsigned */
+		lhs = (natural_t) lhs >> rhs;
+	    }
+	    t = db_read_token();
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+boolean_t
+db_logical_relation_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+	char		op[3];
+
+	if (!db_shift_expr(&lhs))
+	    return(FALSE);
+
+	t = db_read_token();
+	while (t == tLOG_EQ || t == tLOG_NOT_EQ
+		|| t == tGREATER || t == tGREATER_EQ
+		|| t == tLESS || t == tLESS_EQ) {
+	    op[0] = db_tok_string[0];
+	    op[1] = db_tok_string[1];
+	    op[2] = 0;
+	    if (!db_shift_expr(&rhs)) {
+		db_printf("Expression syntax error after \"%s\"\n", op);
+		db_error(0);
+		/*NOTREACHED*/
+	    }
+	    switch(t) {
+	    case tLOG_EQ:
+		lhs = (lhs == rhs);
+		break;
+	    case tLOG_NOT_EQ:
+		lhs = (lhs != rhs);
+		break;
+	    case tGREATER:
+		lhs = (lhs > rhs);
+		break;
+	    case tGREATER_EQ:
+		lhs = (lhs >= rhs);
+		break;
+	    case tLESS:
+		lhs = (lhs < rhs);
+		break;
+	    case tLESS_EQ:
+		lhs = (lhs <= rhs);
+		break;
+	    }
+	    t = db_read_token();
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+boolean_t
+db_logical_and_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+
+	if (!db_logical_relation_expr(&lhs))
+	    return(FALSE);
+
+	t = db_read_token();
+	while (t == tLOG_AND) {
+	    if (!db_logical_relation_expr(&rhs)) {
+		db_error("Expression syntax error after \"&&\"\n");
+		/*NOTREACHED*/
+	    }
+	    lhs = (lhs && rhs);
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+boolean_t
+db_logical_or_expr(valuep)
+	db_expr_t *valuep;
+{
+	db_expr_t	lhs, rhs;
+	int		t;
+
+	if (!db_logical_and_expr(&lhs))
+	    return(FALSE);
+
+	t = db_read_token();
+	while (t == tLOG_OR) {
+	    if (!db_logical_and_expr(&rhs)) {
+		db_error("Expression syntax error after \"||\"\n");
+		/*NOTREACHED*/
+	    }
+	    lhs = (lhs || rhs);
+	}
+	db_unread_token(t);
+	*valuep = lhs;
+	return (TRUE);
+}
+
+int
+db_expression(valuep)
+	db_expr_t *valuep;
+{
+	return (db_logical_or_expr(valuep));
+}
+
+#endif MACH_KDB