Add a small set of logical operators to DDB command language.

This are based on Mach3.
Documentation is pending but has been promised.

Submitted by:	Dan Partelly
Reviewed by:	adrian, jhb (older version)

Differential Revision:	https://reviews.freebsd.org/D4230
RelNotes:	yes
This commit is contained in:
Pedro F. Giffuni 2016-05-16 19:42:38 +00:00
parent 3c4efeae16
commit c69cee69f9
Notes: svn2git 2020-12-20 02:59:44 +00:00
svn path=/head/; revision=299970
4 changed files with 216 additions and 27 deletions

View File

@ -225,6 +225,10 @@ db_print_cmd(db_expr_t addr, bool have_addr, db_expr_t count, char *modif)
else
db_printf("\\%03o", (int)value);
break;
default:
db_print_format = 'x';
db_error("Syntax error: unsupported print modifier\n");
/*NOTREACHED*/
}
db_printf("\n");
}

View File

@ -43,6 +43,9 @@ static bool db_mult_expr(db_expr_t *valuep);
static bool db_shift_expr(db_expr_t *valuep);
static bool db_term(db_expr_t *valuep);
static bool db_unary(db_expr_t *valuep);
static bool db_logical_or_expr(db_expr_t *valuep);
static bool db_logical_and_expr(db_expr_t *valuep);
static bool db_logical_relation_expr(db_expr_t *valuep);
static bool
db_term(db_expr_t *valuep)
@ -108,19 +111,40 @@ db_unary(db_expr_t *valuep)
t = db_read_token();
if (t == tMINUS) {
if (!db_unary(valuep)) {
db_error("Syntax error\n");
db_printf("Expression syntax error after '%c'\n", '-');
db_error(NULL);
/*NOTREACHED*/
}
*valuep = -*valuep;
return (true);
}
if (t == tEXCL) {
if(!db_unary(valuep)) {
db_printf("Expression syntax error after '%c'\n", '!');
db_error(NULL);
/* NOTREACHED */
}
*valuep = (!(*valuep));
return (true);
}
if (t == tBIT_NOT) {
if(!db_unary(valuep)) {
db_printf("Expression syntax error after '%c'\n", '~');
db_error(NULL);
/* NOTREACHED */
}
*valuep = (~(*valuep));
return (true);
}
if (t == tSTAR) {
/* indirection */
if (!db_unary(valuep)) {
db_error("Syntax error\n");
db_printf("Expression syntax error after '%c'\n", '*');
db_error(NULL);
/*NOTREACHED*/
}
*valuep = db_get_value((db_addr_t)*valuep, sizeof(void *), false);
*valuep = db_get_value((db_addr_t)*valuep, sizeof(void *),
false);
return (true);
}
db_unread_token(t);
@ -137,24 +161,31 @@ db_mult_expr(db_expr_t *valuep)
return (false);
t = db_read_token();
while (t == tSTAR || t == tSLASH || t == tPCT || t == tHASH) {
while (t == tSTAR || t == tSLASH || t == tPCT || t == tHASH ||
t == tBIT_AND ) {
if (!db_term(&rhs)) {
db_error("Syntax error\n");
db_printf("Expression syntax error after '%c'\n", '!');
db_error(NULL);
/*NOTREACHED*/
}
if (t == tSTAR)
lhs *= rhs;
else {
if (rhs == 0) {
db_error("Divide by 0\n");
/*NOTREACHED*/
}
if (t == tSLASH)
lhs /= rhs;
else if (t == tPCT)
lhs %= rhs;
else
lhs = roundup(lhs, rhs);
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 = roundup(lhs, rhs);
}
t = db_read_token();
}
@ -168,20 +199,32 @@ db_add_expr(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) {
while (t == tPLUS || t == tMINUS || t == tBIT_OR) {
if (!db_mult_expr(&rhs)) {
db_error("Syntax error\n");
c = db_tok_string[0];
db_printf("Expression syntax error after '%c'\n", c);
db_error(NULL);
/*NOTREACHED*/
}
if (t == tPLUS)
switch (t) {
case tPLUS:
lhs += rhs;
else
break;
case tMINUS:
lhs -= rhs;
break;
case tBIT_OR:
lhs |= rhs;
break;
default:
__unreachable();
}
t = db_read_token();
}
db_unread_token(t);
@ -196,8 +239,7 @@ db_shift_expr(db_expr_t *valuep)
int t;
if (!db_add_expr(&lhs))
return (false);
return (false);
t = db_read_token();
while (t == tSHIFT_L || t == tSHIFT_R) {
if (!db_add_expr(&rhs)) {
@ -221,8 +263,109 @@ db_shift_expr(db_expr_t *valuep)
return (true);
}
static bool
db_logical_relation_expr(
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(NULL);
/*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;
default:
__unreachable();
}
t = db_read_token();
}
db_unread_token(t);
*valuep = lhs;
return (true);
}
static bool
db_logical_and_expr(
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_printf("Expression syntax error after '%s'\n", "&&");
db_error(NULL);
/*NOTREACHED*/
}
lhs = (lhs && rhs);
t = db_read_token();
}
db_unread_token(t);
*valuep = lhs;
return (true);
}
static bool
db_logical_or_expr(
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_printf("Expression syntax error after '%s'\n", "||");
db_error(NULL);
/*NOTREACHED*/
}
lhs = (lhs || rhs);
t = db_read_token();
}
db_unread_token(t);
*valuep = lhs;
return (true);
}
int
db_expression(db_expr_t *valuep)
{
return (db_shift_expr(valuep));
return (db_logical_or_expr(valuep));
}

View File

@ -274,6 +274,10 @@ db_lex(void)
case '/':
return (tSLASH);
case '=':
c = db_read_char();
if (c == '=')
return (tLOG_EQ);
db_unread_char(c);
return (tEQ);
case '%':
return (tPCT);
@ -290,21 +294,46 @@ db_lex(void)
case '$':
return (tDOLLAR);
case '!':
c = db_read_char();
if (c == '='){
return (tLOG_NOT_EQ);
}
db_unread_char(c);
return (tEXCL);
case ';':
return (tSEMI);
case '&':
c = db_read_char();
if (c == '&')
return (tLOG_AND);
db_unread_char(c);
return (tBIT_AND);
case '|':
c = db_read_char();
if (c == '|')
return (tLOG_OR);
db_unread_char(c);
return (tBIT_OR);
case '<':
c = db_read_char();
if (c == '<')
return (tSHIFT_L);
if (c == '=')
return (tLESS_EQ);
db_unread_char(c);
break;
return (tLESS);
case '>':
c = db_read_char();
if (c == '>')
return (tSHIFT_R);
if (c == '=')
return (tGREATER_EQ);
db_unread_char(c);
break;
return (tGREATER);
case '?':
return (tQUESTION);
case '~':
return (tBIT_NOT);
case -1:
return (tEOF);
}

View File

@ -69,5 +69,18 @@ extern char db_tok_string[TOK_STRING_SIZE];
#define tSHIFT_R 19
#define tDOTDOT 20
#define tSEMI 21
#define tLOG_EQ 22
#define tLOG_NOT_EQ 23
#define tLESS 24
#define tLESS_EQ 25
#define tGREATER 26
#define tGREATER_EQ 27
#define tBIT_AND 28
#define tBIT_OR 29
#define tLOG_AND 30
#define tLOG_OR 31
#define tSTRING 32
#define tQUESTION 33
#define tBIT_NOT 34
#endif /* !_DDB_DB_LEX_H_ */