sys/src/cmd/db/command.c

   1 /*
   2  *
   3  *      debugger
   4  *
   5  */
   6
   7 #include "defs.h"
   8 #include "fns.h"
   9
  10 char    BADEQ[] = "unexpected `='";
  11
  12 BOOL    executing;
  13 extern  Rune    *lp;
  14
  15 char    eqformat[ARB] = "z";
  16 char    stformat[ARB] = "zMi";
  17
  18 ADDR    ditto;
  19
  20 ADDR    dot;
  21 int     dotinc;
  22 WORD    adrval, cntval, loopcnt;
  23 int     adrflg, cntflg;
  24
  25 /* command decoding */
  26
  27 command(char *buf, int defcom)
  28 {
  29         char    *reg;
  30         char    savc;
  31         Rune    *savlp=lp;
  32         char    savlc = lastc;
  33         char    savpc = peekc;
  34         static char lastcom = '=', savecom = '=';
  35
  36         if (defcom == 0)
  37                 defcom = lastcom;
  38         if (buf) {
  39                 if (*buf==EOR)
  40                         return(FALSE);
  41                 clrinp();
  42                 lp=(Rune*)buf;
  43         }
  44         do {
  45                 adrflg=expr(0);         /* first address */
  46                 if (adrflg){
  47                         dot=expv;
  48                         ditto=expv;
  49                 }
  50                 adrval=dot;
  51
  52                 if (rdc()==',' && expr(0)) {    /* count */
  53                         cntflg=TRUE;
  54                         cntval=expv;
  55                 } else {
  56                         cntflg=FALSE;
  57                         cntval=1;
  58                         reread();
  59                 }
  60
  61                 if (!eol(rdc()))
  62                         lastcom=lastc;          /* command */
  63                 else {
  64                         if (adrflg==0)
  65                                 dot=inkdot(dotinc);
  66                         reread();
  67                         lastcom=defcom;
  68                 }
  69                 switch(lastcom) {
  70                 case '/':
  71                 case '=':
  72                 case '?':
  73                         savecom = lastcom;
  74                         acommand(lastcom);
  75                         break;
  76
  77                 case '>':
  78                         lastcom = savecom;
  79                         savc=rdc();
  80                         if (reg=regname(savc))
  81                                 rput(cormap, reg, dot);
  82                         else
  83                                 error("bad variable");
  84                         break;
  85
  86                 case '!':
  87                         lastcom=savecom;
  88                         shell();
  89                         break;
  90
  91                 case '$':
  92                         lastcom=savecom;
  93                         printtrace(nextchar());
  94                         break;
  95
  96                 case ':':
  97                         if (!executing) {
  98                                 executing=TRUE;
  99                                 subpcs(nextchar());
 100                                 executing=FALSE;
 101                                 lastcom=savecom;
 102                         }
 103                         break;
 104
 105                 case 0:
 106                         prints(DBNAME);
 107                         break;
 108
 109                 default:
 110                         error("bad command");
 111                 }
 112                 flushbuf();
 113         } while (rdc()==';');
 114         if (buf == 0)
 115                 reread();
 116         else {
 117                 clrinp();
 118                 lp=savlp;
 119                 lastc = savlc;
 120                 peekc = savpc;
 121         }
 122
 123         if(adrflg)
 124                 return dot;
 125         return 1;
 126 }
 127
 128 /*
 129  * [/?][wml]
 130  */
 131
 132 void
 133 acommand(int pc)
 134 {
 135         int eqcom;
 136         Map *map;
 137         char *fmt;
 138         char buf[512];
 139
 140         if (pc == '=') {
 141                 eqcom = 1;
 142                 fmt = eqformat;
 143                 map = dotmap;
 144         } else {
 145                 eqcom = 0;
 146                 fmt = stformat;
 147                 if (pc == '/')
 148                         map = cormap;
 149                 else
 150                         map = symmap;
 151         }
 152         if (!map) {
 153                 snprint(buf, sizeof(buf), "no map for %c", pc);
 154                 error(buf);
 155         }
 156
 157         switch (rdc())
 158         {
 159         case 'm':
 160                 if (eqcom)
 161                         error(BADEQ);
 162                 cmdmap(map);
 163                 break;
 164
 165         case 'L':
 166         case 'l':
 167                 if (eqcom)
 168                         error(BADEQ);
 169                 cmdsrc(lastc, map);
 170                 break;
 171
 172         case 'W':
 173         case 'w':
 174                 if (eqcom)
 175                         error(BADEQ);
 176                 cmdwrite(lastc, map);
 177                 break;
 178
 179         default:
 180                 reread();
 181                 getformat(fmt);
 182                 scanform(cntval, !eqcom, fmt, map, eqcom);
 183         }
 184 }
 185
 186 void
 187 cmdsrc(int c, Map *map)
 188 {
 189         ulong w;
 190         long locval, locmsk;
 191         ADDR savdot;
 192         ushort sh;
 193         char buf[512];
 194         int ret;
 195
 196         if (c == 'L')
 197                 dotinc = 4;
 198         else
 199                 dotinc = 2;
 200         savdot=dot;
 201         expr(1);
 202         locval=expv;
 203         if (expr(0))
 204                 locmsk=expv;
 205         else
 206                 locmsk = ~0;
 207         if (c == 'L')
 208                 while ((ret = get4(map, dot, &w)) > 0 &&  (w&locmsk) != locval)
 209                         dot = inkdot(dotinc);
 210         else
 211                 while ((ret = get2(map, dot, &sh)) > 0 && (sh&locmsk) != locval)
 212                         dot = inkdot(dotinc);
 213         if (ret < 0) {
 214                 dot=savdot;
 215                 error("%r");
 216         }
 217         symoff(buf, 512, dot, CANY);
 218         dprint(buf);
 219 }
 220
 221 static char badwrite[] = "can't write process memory or text image";
 222
 223 void
 224 cmdwrite(int wcom, Map *map)
 225 {
 226         ADDR savdot;
 227         char *format;
 228         int pass;
 229
 230         if (wcom == 'w')
 231                 format = "x";
 232         else
 233                 format = "X";
 234         expr(1);
 235         pass = 0;
 236         do {
 237                 pass++;
 238                 savdot=dot;
 239                 exform(1, 1, format, map, 0, pass);
 240                 dot=savdot;
 241                 if (wcom == 'W') {
 242                         if (put4(map, dot, expv) <= 0)
 243                                 error(badwrite);
 244                 } else {
 245                         if (put2(map, dot, expv) <= 0)
 246                                 error(badwrite);
 247                 }
 248                 savdot=dot;
 249                 dprint("=%8t");
 250                 exform(1, 0, format, map, 0, pass);
 251                 newline();
 252         } while (expr(0));
 253         dot=savdot;
 254 }
 255
 256 /*
 257  * collect a register name; return register offset
 258  * this is not what i'd call a good division of labour
 259  */
 260
 261 char *
 262 regname(int regnam)
 263 {
 264         static char buf[64];
 265         char *p;
 266         int c;
 267
 268         p = buf;
 269         *p++ = regnam;
 270         while (isalnum(c = readchar())) {
 271                 if (p >= buf+sizeof(buf)-1)
 272                         error("register name too long");
 273                 *p++ = c;
 274         }
 275         *p = 0;
 276         reread();
 277         return (buf);
 278 }
 279
 280 /*
 281  * shell escape
 282  */
 283
 284 void
 285 shell(void)
 286 {
 287         int     rc, unixpid;
 288         char *argp = (char*)lp;
 289
 290         while (lastc!=EOR)
 291                 rdc();
 292         if ((unixpid=fork())==0) {
 293                 *lp=0;
 294                 execl("/bin/rc", "rc", "-c", argp, nil);
 295                 exits("execl");                         /* botch */
 296         } else if (unixpid == -1) {
 297                 error("cannot fork");
 298         } else {
 299                 mkfault = 0;
 300                 while ((rc = waitpid()) != unixpid){
 301                         if(rc == -1 && mkfault){
 302                                 mkfault = 0;
 303                                 continue;
 304                         }
 305                         break;
 306                 }
 307                 prints("!");
 308                 reread();
 309         }
 310 }