sys/ddb/db_command.c

/*
 * 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
 * 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 the
 * rights to redistribute these changes.
 *
 *      $Id$
 */

/*
 *      Author: David B. Golub, Carnegie Mellon University
 *      Date:   7/90
 */

/*
 * Command dispatcher.
 */
#include "param.h"
#include "proc.h"
#include <machine/db_machdep.h>         /* type definitions */

#include <ddb/db_lex.h>
#include <ddb/db_output.h>

#include <setjmp.h>

/*
 * Exported global variables
 */
boolean_t       db_cmd_loop_done;
jmp_buf         db_jmpbuf;
db_addr_t       db_dot;
db_addr_t       db_last_addr;
db_addr_t       db_prev;
db_addr_t       db_next;

/*
 * if 'ed' style: 'dot' is set at start of last item printed,
 * and '+' points to next line.
 * Otherwise: 'dot' points to next item, '..' points to last.
 */
boolean_t       db_ed_style = TRUE;


/*
 * Utility routine - discard tokens through end-of-line.
 */
void
db_skip_to_eol()
{
        int     t;
        do {
            t = db_read_token();
        } while (t != tEOL);
}

/*
 * Command table
 */
struct command {
        char *  name;           /* command name */
        void    (*fcn)();       /* function to call */
        int     flag;           /* extra info: */
#define CS_OWN          0x1         /* non-standard syntax */
#define CS_MORE         0x2         /* standard syntax, but may have other
                                       words at end */
#define CS_SET_DOT      0x100       /* set dot after command */
        struct command *more;   /* another level of command */
};

/*
 * Results of command search.
 */
#define CMD_UNIQUE      0
#define CMD_FOUND       1
#define CMD_NONE        2
#define CMD_AMBIGUOUS   3
#define CMD_HELP        4

/*
 * Search for command prefix.
 */
int
db_cmd_search(name, table, cmdp)
        char *          name;
        struct command  *table;
        struct command  **cmdp; /* out */
{
        struct command  *cmd;
        int             result = CMD_NONE;

        for (cmd = table; cmd->name != 0; cmd++) {
            register char *lp;
            register char *rp;
            register int  c;

            lp = name;
            rp = cmd->name;
            while ((c = *lp) == *rp) {
                if (c == 0) {
                    /* complete match */
                    *cmdp = cmd;
                    return (CMD_UNIQUE);
                }
                lp++;
                rp++;
            }
            if (c == 0) {
                /* end of name, not end of command -
                   partial match */
                if (result == CMD_FOUND) {
                    result = CMD_AMBIGUOUS;
                    /* but keep looking for a full match -
                       this lets us match single letters */
                }
                else {
                    *cmdp = cmd;
                    result = CMD_FOUND;
                }
            }
        }
        if (result == CMD_NONE) {
            /* check for 'help' */
                if (name[0] == 'h' && name[1] == 'e'
                    && name[2] == 'l' && name[3] == 'p')
                        result = CMD_HELP;
        }
        return (result);
}

void
db_cmd_list(table)
        struct command *table;
{
        register struct command *cmd;

        for (cmd = table; cmd->name != 0; cmd++) {
            db_printf("%-12s", cmd->name);
            db_end_line();
        }
}

void
db_command(last_cmdp, cmd_table)
        struct command  **last_cmdp;    /* IN_OUT */
        struct command  *cmd_table;
{
        struct command  *cmd;
        int             t;
        char            modif[TOK_STRING_SIZE];
        db_expr_t       addr, count;
        boolean_t       have_addr;
        int             result;

        t = db_read_token();
        if (t == tEOL) {
            /* empty line repeats last command, at 'next' */
            cmd = *last_cmdp;
            addr = (db_expr_t)db_next;
            have_addr = FALSE;
            count = 1;
            modif[0] = '\0';
        }
        else if (t == tEXCL) {
            void db_fncall();
            db_fncall();
            return;
        }
        else if (t != tIDENT) {
            db_printf("?\n");
            db_flush_lex();
            return;
        }
        else {
            /*
             * Search for command
             */
            while (cmd_table) {
                result = db_cmd_search(db_tok_string,
                                       cmd_table,
                                       &cmd);
                switch (result) {
                    case CMD_NONE:
                        db_printf("No such command\n");
                        db_flush_lex();
                        return;
                    case CMD_AMBIGUOUS:
                        db_printf("Ambiguous\n");
                        db_flush_lex();
                        return;
                    case CMD_HELP:
                        db_cmd_list(cmd_table);
                        db_flush_lex();
                        return;
                    default:
                        break;
                }
                if ((cmd_table = cmd->more) != 0) {
                    t = db_read_token();
                    if (t != tIDENT) {
                        db_cmd_list(cmd_table);
                        db_flush_lex();
                        return;
                    }
                }
            }

            if ((cmd->flag & CS_OWN) == 0) {
                /*
                 * Standard syntax:
                 * command [/modifier] [addr] [,count]
                 */
                t = db_read_token();
                if (t == tSLASH) {
                    t = db_read_token();
                    if (t != tIDENT) {
                        db_printf("Bad modifier\n");
                        db_flush_lex();
                        return;
                    }
                    db_strcpy(modif, db_tok_string);
                }
                else {
                    db_unread_token(t);
                    modif[0] = '\0';
                }

                if (db_expression(&addr)) {
                    db_dot = (db_addr_t) addr;
                    db_last_addr = db_dot;
                    have_addr = TRUE;
                }
                else {
                    addr = (db_expr_t) db_dot;
                    have_addr = FALSE;
                }
                t = db_read_token();
                if (t == tCOMMA) {
                    if (!db_expression(&count)) {
                        db_printf("Count missing\n");
                        db_flush_lex();
                        return;
                    }
                }
                else {
                    db_unread_token(t);
                    count = -1;
                }
                if ((cmd->flag & CS_MORE) == 0) {
                    db_skip_to_eol();
                }
            }
        }
        *last_cmdp = cmd;
        if (cmd != 0) {
            /*
             * Execute the command.
             */
            (*cmd->fcn)(addr, have_addr, count, modif);

            if (cmd->flag & CS_SET_DOT) {
                /*
                 * If command changes dot, set dot to
                 * previous address displayed (if 'ed' style).
                 */
                if (db_ed_style) {
                    db_dot = db_prev;
                }
                else {
                    db_dot = db_next;
                }
            }
            else {
                /*
                 * If command does not change dot,
                 * set 'next' location to be the same.
                 */
                db_next = db_dot;
            }
        }
}

/*
 * 'show' commands
 */
extern void     db_listbreak_cmd();
extern void     db_listwatch_cmd();
extern void     db_show_regs(), db_show_one_thread(), db_show_all_threads();
extern void     vm_map_print(), vm_object_print(), vm_page_print();
extern void     ipc_port_print();
void            db_show_help();

struct command db_show_all_cmds[] = {
#if 0
        { "threads",    db_show_all_threads,0,  0 },
#endif
        { (char *)0 }
};

struct command db_show_cmds[] = {
        { "all",        0,                      0,      db_show_all_cmds },
        { "registers",  db_show_regs,           0,      0 },
        { "breaks",     db_listbreak_cmd,       0,      0 },
        { "watches",    db_listwatch_cmd,       0,      0 },
#if 0
        { "thread",     db_show_one_thread,     0,      0 },
#endif
        { "map",        vm_map_print,           0,      0 },
        { "object",     vm_object_print,        0,      0 },
#if 0
        { "page",       vm_page_print,          0,      0 },
#endif
#if 0
        { "port",       ipc_port_print,         0,      0 },
#endif
        { (char *)0, }
};

extern void     db_print_cmd(), db_examine_cmd(), db_set_cmd();
extern void     db_search_cmd();
extern void     db_write_cmd();
extern void     db_delete_cmd(), db_breakpoint_cmd();
extern void     db_deletewatch_cmd(), db_watchpoint_cmd();
extern void     db_single_step_cmd(), db_trace_until_call_cmd(),
                db_trace_until_matching_cmd(), db_continue_cmd();
extern void     db_stack_trace_cmd();
void            db_help_cmd();
void            db_fncall();

struct command db_command_table[] = {
        { "print",      db_print_cmd,           0,      0 },
        { "examine",    db_examine_cmd,         CS_SET_DOT, 0 },
        { "x",          db_examine_cmd,         CS_SET_DOT, 0 },
        { "search",     db_search_cmd,          CS_OWN|CS_SET_DOT, 0 },
        { "set",        db_set_cmd,             CS_OWN, 0 },
        { "write",      db_write_cmd,           CS_MORE|CS_SET_DOT, 0 },
        { "w",          db_write_cmd,           CS_MORE|CS_SET_DOT, 0 },
        { "delete",     db_delete_cmd,          0,      0 },
        { "d",          db_delete_cmd,          0,      0 },
        { "break",      db_breakpoint_cmd,      0,      0 },
        { "dwatch",     db_deletewatch_cmd,     0,      0 },
        { "watch",      db_watchpoint_cmd,      CS_MORE,0 },
        { "step",       db_single_step_cmd,     0,      0 },
        { "s",          db_single_step_cmd,     0,      0 },
        { "continue",   db_continue_cmd,        0,      0 },
        { "c",          db_continue_cmd,        0,      0 },
        { "until",      db_trace_until_call_cmd,0,      0 },
        { "next",       db_trace_until_matching_cmd,0,  0 },
        { "match",      db_trace_until_matching_cmd,0,  0 },
        { "trace",      db_stack_trace_cmd,     0,      0 },
        { "call",       db_fncall,              CS_OWN, 0 },
        { "show",       0,                      0,      db_show_cmds },
        { (char *)0, }
};

struct command  *db_last_command = 0;

void
db_help_cmd()
{
        struct command *cmd = db_command_table;

        while (cmd->name != 0) {
            db_printf("%-12s", cmd->name);
            db_end_line();
            cmd++;
        }
}

void
db_command_loop()
{
        /*
         * Initialize 'prev' and 'next' to dot.
         */
        db_prev = db_dot;
        db_next = db_dot;

        db_cmd_loop_done = 0;
        while (!db_cmd_loop_done) {

            (void) setjmp(db_jmpbuf);
            if (db_print_position() != 0)
                db_printf("\n");

            db_printf("db> ");
            (void) db_read_line();

            db_command(&db_last_command, db_command_table);
        }
}

void
db_error(s)
        char *s;
{
        if (s)
            db_printf(s);
        db_flush_lex();
        longjmp(db_jmpbuf, 1);
}


/*
 * Call random function:
 * !expr(arg,arg,arg)
 */
void
db_fncall()
{
        db_expr_t       fn_addr;
#define MAXARGS         11
        db_expr_t       args[MAXARGS];
        int             nargs = 0;
        db_expr_t       retval;
        db_expr_t       (*func)();
        int             t;

        if (!db_expression(&fn_addr)) {
            db_printf("Bad function\n");
            db_flush_lex();
            return;
        }
        func = (db_expr_t (*) ()) fn_addr;

        t = db_read_token();
        if (t == tLPAREN) {
            if (db_expression(&args[0])) {
                nargs++;
                while ((t = db_read_token()) == tCOMMA) {
                    if (nargs == MAXARGS) {
                        db_printf("Too many arguments\n");
                        db_flush_lex();
                        return;
                    }
                    if (!db_expression(&args[nargs])) {
                        db_printf("Argument missing\n");
                        db_flush_lex();
                        return;
                    }
                    nargs++;
                }
                db_unread_token(t);
            }
            if (db_read_token() != tRPAREN) {
                db_printf("?\n");
                db_flush_lex();
                return;
            }
        }
        db_skip_to_eol();

        while (nargs < MAXARGS) {
            args[nargs++] = 0;
        }

        retval = (*func)(args[0], args[1], args[2], args[3], args[4],
                         args[5], args[6], args[7], args[8], args[9] );
        db_printf("%#n\n", retval);
}