compiler/clib/__exec.c

   1 /*
   2     Copyright © 2008-2012, The AROS Development Team. All rights reserved.
   3     $Id$
   4
   5     Support functions for POSIX exec*() functions.
   6 */
   7 #include <exec/types.h>
   8 #include <dos/dos.h>
   9 #include <proto/dos.h>
  10
  11 #include <aros/libcall.h>
  12
  13 #include <errno.h>
  14 #include <ctype.h>
  15 #include <assert.h>
  16 #include <string.h>
  17 #include <stdlib.h>
  18 #include <stdarg.h>
  19 #include <unistd.h>
  20 #include <sys/stat.h>
  21 #include <fcntl.h>
  22
  23 #include "__arosc_privdata.h"
  24 #include "__exec.h"
  25 #include "__upath.h"
  26 #include "__fdesc.h"
  27 #include "__vfork.h"
  28
  29 #define DEBUG 0
  30 #include <aros/debug.h>
  31
  32 static BOOL containswhite(const char *str);
  33 static char *escape(const char *str);
  34 static char *appendarg(char *argptr, int *argptrsize, const char *arg, APTR pool);
  35 static char *appendargs(char *argptr, int *argptrsize, char *const args[], APTR pool);
  36 static void __exec_cleanup(struct aroscbase *aroscbase);
  37 static void close_on_exec(struct aroscbase *aroscbase);
  38
  39 /* Public functions */
  40 /********************/
  41
  42 APTR __exec_prepare(const char *filename, int searchpath, char *const argv[], char *const envp[])
  43 {
  44     struct aroscbase *aroscbase = __GM_GetBase();
  45     char *filename2 = NULL;
  46     int argssize = 512;
  47     struct Process *me;
  48
  49     D(bug("Entering __exec_prepare(\"%s\", %d, %x, %x)\n",
  50           filename, searchpath, argv, envp
  51     ));
  52     /* Sanity check */
  53     if (filename == NULL || filename[0] == '\0' || argv == NULL)
  54     {
  55         errno = EINVAL;
  56         goto error;
  57     }
  58
  59     /* Use own memory to allocate so that no arosstdc.library functions need to be called
  60        exec_pool can also be allocated in __exec_valist2array
  61     */
  62     if (!aroscbase->acb_exec_pool)
  63         aroscbase->acb_exec_pool = CreatePool(MEMF_PUBLIC, 1024, 512);
  64     if (!aroscbase->acb_exec_pool)
  65     {
  66         errno = ENOMEM;
  67         goto error;
  68     }
  69
  70     aroscbase->acb_exec_args = AllocPooled(aroscbase->acb_exec_pool, argssize);
  71     aroscbase->acb_exec_args[0] = '\0';
  72
  73     /* Search path if asked and no directory separator is present in the file */
  74     if (searchpath && index(filename, '/') == NULL && index(filename, ':') == NULL)
  75     {
  76         int i, len, size;
  77         char *path = NULL, *path_ptr, *path_item;
  78         BPTR lock;
  79
  80         if (environ)
  81         {
  82             for (i=0; environ[i]; i++)
  83             {
  84                 if (strncmp(environ[i], "PATH=", 5) == 0)
  85                 {
  86                     path = &environ[i][5];
  87                     break;
  88                 }
  89             }
  90         }
  91
  92         if (!path)
  93             path = getenv("PATH");
  94
  95         if (!path)
  96             path = ":/bin:/usr/bin";
  97
  98         D(bug("__exec_prepare: PATH('%s')\n", path));
  99
 100         path_ptr = AllocPooled(aroscbase->acb_exec_pool, strlen(path) + 1);
 101         strcpy(path_ptr, path);
 102         path = path_ptr;
 103
 104         D(bug("__exec_prepare: PATH('%s')\n", path));
 105
 106         size = 128;
 107         filename2 = AllocPooled(aroscbase->acb_exec_pool, size);
 108         if (!filename2)
 109         {
 110             errno = ENOMEM;
 111             goto error;
 112         }
 113
 114         for(path_ptr = path, lock = (BPTR)NULL, path_item = strsep(&path_ptr, ",:");
 115             lock == (BPTR)NULL && path_item != NULL;
 116             path_item = strsep(&path_ptr, ",:")
 117         )
 118         {
 119             if(path_item[0] == '\0')
 120                 path_item = ".";
 121
 122             len = strlen(path_item) + strlen(filename) + 2;
 123
 124             if (len > size)
 125             {
 126                 FreePooled(aroscbase->acb_exec_pool, filename2, size);
 127                 size = len;
 128                 filename2 = AllocPooled(aroscbase->acb_exec_pool, size);
 129                 if (!filename2)
 130                 {
 131                     errno = ENOMEM;
 132                     goto error;
 133                 }
 134             }
 135
 136             strcpy(filename2, path_item);
 137             strcat(filename2, "/");
 138             strcat(filename2, filename);
 139             lock = Lock(__path_u2a(filename2), SHARED_LOCK);
 140             D(bug("__exec_prepare: Lock(\"%s\") == %x\n", filename2, (APTR)lock));
 141         }
 142
 143         if(lock != (BPTR)NULL)
 144             UnLock(lock);
 145         else
 146         {
 147             errno = ENOENT;
 148             goto error;
 149         }
 150     }
 151     else
 152         filename2 = (char *)filename;
 153
 154
 155     if (aroscbase->acb_flags & PRETEND_CHILD)
 156     {
 157         struct vfork_data *udata = aroscbase->acb_vfork_data;
 158
 159         udata->exec_filename = filename2;
 160         udata->exec_argv = argv;
 161         udata->exec_envp = envp;
 162
 163         /* Set this so the child knows that __exec_prepare was called */
 164         udata->child_executed = 1;
 165
 166         D(bug("__exec_prepare: Calling child\n"));
 167         /* Now call child process, so it will call __exec_prepare */
 168         Signal(udata->child, 1 << udata->child_signal);
 169
 170         D(bug("__exec_prepare: Waiting for child to finish __exec_prepare\n"));
 171         /* __exec_prepare should be finished now on child */
 172         Wait(1 << udata->parent_signal);
 173
 174         if (!udata->exec_id)
 175         {
 176             D(bug("__exec_prepare: Continue child immediately on error\n"));
 177             Signal(udata->child, 1 << udata->child_signal);
 178         }
 179
 180         D(bug("__exec_prepare: Exiting from forked __exec_prepare id=%x, errno=%d\n",
 181               udata->exec_id, udata->child_errno
 182         ));
 183
 184         return aroscbase;
 185     }
 186
 187     D(bug("__exec_prepare: Not running as PRETEND_CHILD\n"));
 188     aroscbase->acb_exec_args = AllocPooled(aroscbase->acb_exec_pool, argssize);
 189     aroscbase->acb_exec_args[0] = '\0';
 190
 191     /* Let's check if it's a script */
 192     BPTR fh = Open((CONST_STRPTR)__path_u2a(filename2), MODE_OLDFILE);
 193     if(fh)
 194     {
 195         if(FGetC(fh) == '#' && FGetC(fh) == '!')
 196         {
 197            char firstline[128], *linebuf, *inter, *interargs = NULL;
 198
 199             /* It is a script, let's read the first line */
 200             if(FGets(fh, (STRPTR)firstline, sizeof(firstline) - 1))
 201             {
 202                 /* delete end of line if present */
 203                 if(firstline[0] && firstline[strlen(firstline)-1] == '\n')
 204                     firstline[strlen(firstline)-1] = '\0';
 205                 linebuf = firstline;
 206                 while(isblank(*linebuf)) linebuf++;
 207                 if(*linebuf != '\0')
 208                 {
 209                     /* Interpreter name is here */
 210                     inter = linebuf;
 211                     while(*linebuf != '\0' && !isblank(*linebuf)) linebuf++;
 212                     if(*linebuf != '\0')
 213                     {
 214                         *linebuf++ = '\0';
 215                         while(isblank(*linebuf)) linebuf++;
 216                         if(*linebuf != '\0')
 217                             /* Interpreter arguments are here */
 218                             interargs = linebuf;
 219                     }
 220
 221                     /* Add interpeter args and the script name to command line args */
 222                     char *args[] = {NULL, NULL, NULL};
 223                     if (interargs)
 224                     {
 225                         args[0] = interargs;
 226                         args[1] = filename2;
 227                     }
 228                     else
 229                     {
 230                         args[0] = filename2;
 231                     }
 232                     aroscbase->acb_exec_args = appendargs(
 233                         aroscbase->acb_exec_args, &argssize, args, aroscbase->acb_exec_pool
 234                     );
 235                     if (!aroscbase->acb_exec_args)
 236                     {
 237                         errno = ENOMEM;
 238                         goto error;
 239                     }
 240
 241                     /* Set file to execute as the script interpreter */
 242                     filename2 = AllocPooled(aroscbase->acb_exec_pool, strlen(inter) + 1);
 243                     strcpy(filename2, inter);
 244                 }
 245             }
 246         }
 247         Close(fh);
 248     }
 249     else
 250     {
 251         /* Simply assume it doesn't exist */
 252         errno = __arosc_ioerr2errno(IoErr());
 253         goto error;
 254     }
 255
 256     /* Add arguments to command line args */
 257     aroscbase->acb_exec_args = appendargs(aroscbase->acb_exec_args, &argssize, argv + 1, aroscbase->acb_exec_pool);
 258     if (!aroscbase->acb_exec_args)
 259     {
 260         errno = ENOMEM;
 261         goto error;
 262     }
 263
 264     /* End command line args with '\n' */
 265     if(strlen(aroscbase->acb_exec_args) > 0)
 266         aroscbase->acb_exec_args[strlen(aroscbase->acb_exec_args) - 1] = '\n';
 267     else
 268         strcat(aroscbase->acb_exec_args, "\n");
 269
 270     /* let's make some sanity tests */
 271     struct stat st;
 272     if(stat(filename2, &st) == 0)
 273     {
 274         if(!(st.st_mode & S_IXUSR) && !(st.st_mode & S_IXGRP) && !(st.st_mode & S_IXOTH))
 275         {
 276             /* file is not executable */
 277             errno = EACCES;
 278             goto error;
 279         }
 280         if(st.st_mode & S_IFDIR)
 281         {
 282             /* it's a directory */
 283             errno = EACCES;
 284             goto error;
 285         }
 286     }
 287     else
 288     {
 289         /* couldn't stat file */
 290         goto error;
 291     }
 292
 293     /* Set taskname */
 294     aroscbase->acb_exec_taskname = AllocPooled(aroscbase->acb_exec_pool, strlen(filename2) + 1);
 295     if (!aroscbase->acb_exec_taskname)
 296     {
 297         errno = ENOMEM;
 298         goto error;
 299     }
 300     strcpy(aroscbase->acb_exec_taskname, filename2);
 301
 302     /* Load file to execute */
 303     aroscbase->acb_exec_seglist = LoadSeg((CONST_STRPTR)__path_u2a(filename2));
 304     if (!aroscbase->acb_exec_seglist)
 305     {
 306         errno = ENOEXEC;
 307         goto error;
 308     }
 309
 310     me = (struct Process *)FindTask(NULL);
 311
 312     if (envp && envp != environ)
 313     {
 314         struct MinList tempenv;
 315         struct LocalVar *lv, *lv2;
 316         char *const *envit;
 317         int env_ok = 1;
 318
 319         /* Remember previous environment variables so they can be put back
 320          * if something goes wrong
 321          */
 322         NEWLIST(&tempenv);
 323         ForeachNodeSafe(&me->pr_LocalVars, lv, lv2)
 324         {
 325             Remove((struct Node *)lv);
 326             AddTail((struct List *)&tempenv, (struct Node *)lv);
 327         }
 328
 329         NEWLIST(&me->pr_LocalVars);
 330         environ = NULL;
 331
 332         for (envit = envp; *envit && env_ok; envit++)
 333             env_ok = putenv(*envit) == 0;
 334
 335         if (env_ok)
 336             /* Old vars may be freed */
 337             ForeachNodeSafe(&tempenv, lv, lv2)
 338             {
 339                 Remove((struct Node *)lv);
 340                 FreeMem(lv->lv_Value, lv->lv_Len);
 341                 FreeVec(lv);
 342             }
 343         else
 344         {
 345             /* Free new nodes */
 346             ForeachNodeSafe(&me->pr_LocalVars, lv, lv2)
 347             {
 348                 Remove((struct Node *)lv);
 349                 FreeMem(lv->lv_Value, lv->lv_Len);
 350                 FreeVec(lv);
 351             }
 352
 353             /* Put old ones back */
 354             ForeachNodeSafe(&tempenv, lv, lv2)
 355             {
 356                 Remove((struct Node *)lv);
 357                 AddTail((struct List *)&me->pr_LocalVars, (struct Node *)lv);
 358             }
 359
 360             errno = ENOMEM;
 361             goto error;
 362         }
 363     }
 364
 365     /* Set standard files to the standard files from arosc */
 366     fdesc *in = __getfdesc(STDIN_FILENO), *out = __getfdesc(STDOUT_FILENO),
 367         *err = __getfdesc(STDERR_FILENO);
 368
 369     if(in)
 370         aroscbase->acb_exec_oldin = SelectInput(in->fcb->fh);
 371     if(out)
 372         aroscbase->acb_exec_oldout = SelectOutput(out->fcb->fh);
 373     if (err)
 374     {
 375         aroscbase->acb_exec_olderr = me->pr_CES;
 376         me->pr_CES = err->fcb->fh;
 377     }
 378
 379     /* Everything OK */
 380     return (APTR)aroscbase;
 381
 382 error:
 383     __exec_cleanup(aroscbase);
 384
 385     return (APTR)NULL;
 386 }
 387
 388
 389 void __exec_do(APTR id)
 390 {
 391     struct aroscbase *aroscbase = __GM_GetBase();
 392     char *oldtaskname;
 393     struct CommandLineInterface *cli = Cli();
 394     struct Task *self = FindTask(NULL);
 395     LONG returncode;
 396
 397     D(bug("[__exec_do] Entering, id(%x)\n", id));
 398
 399     /* id is unused */
 400     (void)id;
 401     /* When exec is not called under vfork condition id == __GM_GetBase()
 402        When exec is called under vfork condition we need to use __GM_GetBase() in the
 403        parent to check for PRETEND_CHILD and find the udata for signaling the child
 404     */
 405
 406     if (aroscbase->acb_flags & PRETEND_CHILD)
 407     {
 408         struct vfork_data *udata = aroscbase->acb_vfork_data;
 409
 410         D(bug("[__exec_do] PRETEND_CHILD\n"));
 411
 412         close_on_exec(aroscbase);
 413
 414         D(bug("Notify child to call __exec_do\n"));
 415
 416         /* Signal child that __exec_do is called */
 417         Signal(udata->child, 1 << udata->child_signal);
 418
 419         /* Clean up in parent */
 420         __exec_cleanup(aroscbase);
 421
 422         /* Continue as parent process */
 423         _exit(0);
 424
 425         assert(0); /* Should not be reached */
 426         return;
 427     }
 428
 429     D(bug("[__exec_do] !PRETEND_CHILD\n"));
 430
 431     aroscbase->acb_flags |= EXEC_PARENT;
 432
 433     oldtaskname = self->tc_Node.ln_Name;
 434     self->tc_Node.ln_Name = aroscbase->acb_exec_taskname;
 435     SetProgramName((STRPTR)aroscbase->acb_exec_taskname);
 436
 437     returncode = RunCommand(
 438         aroscbase->acb_exec_seglist,
 439         cli->cli_DefaultStack * CLI_DEFAULTSTACK_UNIT,
 440         (STRPTR)aroscbase->acb_exec_args,
 441         strlen(aroscbase->acb_exec_args)
 442     );
 443
 444     self->tc_Node.ln_Name = oldtaskname;
 445     SetProgramName((STRPTR)oldtaskname);
 446
 447     __exec_cleanup(aroscbase);
 448
 449     D(bug("[__exec_do] exiting from non-forked\n"));
 450     _exit(returncode);
 451 }
 452
 453
 454 char *const *__exec_valist2array(const char *arg1, va_list list)
 455 {
 456     struct aroscbase *aroscbase = __GM_GetBase();
 457     int argc, i;
 458     static char *no_arg[] = {NULL};
 459     va_list list2;
 460     char *argit;
 461
 462     assert(aroscbase->acb_exec_tmparray == NULL);
 463
 464     va_copy(list2, list);
 465
 466     if (arg1 == NULL)
 467         return no_arg;
 468
 469     for (argit = va_arg(list, char *), argc = 1;
 470          argit != NULL;
 471          argit = va_arg(list, char *)
 472     )
 473         argc++;
 474
 475     if (!(aroscbase->acb_exec_tmparray = malloc((argc+1)*(sizeof(char *)))))
 476     {
 477         D(bug("__exec_valist2array: Memory allocation failed\n"));
 478         va_end(list2);
 479         return NULL;
 480     }
 481
 482     aroscbase->acb_exec_tmparray[0] = (char *)arg1;
 483     for (argit = va_arg(list2, char *), i = 1;
 484          i <= argc; /* i == argc will copy the NULL pointer */
 485          argit = va_arg(list2, char *), i++
 486     )
 487     {
 488         D(bug("arg %d: %x\n", i, argit));
 489         aroscbase->acb_exec_tmparray[i] = argit;
 490     }
 491
 492     va_end(list2);
 493
 494     return aroscbase->acb_exec_tmparray;
 495 }
 496
 497
 498 void __exec_cleanup_array()
 499 {
 500     struct aroscbase *aroscbase = __GM_GetBase();
 501     if (aroscbase->acb_exec_tmparray)
 502     {
 503         free((void *)aroscbase->acb_exec_tmparray);
 504         aroscbase->acb_exec_tmparray = NULL;
 505     }
 506 }
 507
 508
 509 /* Support functions */
 510 /*********************/
 511
 512 /* Return TRUE if there are any white spaces in the string */
 513 static BOOL containswhite(const char *str)
 514 {
 515     while(*str != '\0')
 516         if(isspace(*str++)) return TRUE;
 517     return FALSE;
 518 }
 519
 520 /* Escape the string and quote it */
 521 static char *escape(const char *str)
 522 {
 523     const char *strptr = str;
 524     char *escaped, *escptr;
 525     /* Additional two characters for '"', and one for '\0' */
 526     int bufsize = strlen(str) + 3;
 527     /* Take into account characters to ecape */
 528     while(*strptr != '\0')
 529     {
 530         switch(*strptr++)
 531         {
 532         case '\n':
 533         case '"':
 534         case '*':
 535             bufsize++;
 536         }
 537     }
 538     escptr = escaped = (char*) malloc(bufsize);
 539     if(!escaped)
 540         return NULL;
 541     *escptr++ = '"';
 542     for(strptr = str; *strptr != '\0'; strptr++)
 543     {
 544         switch(*strptr)
 545         {
 546         case '\n':
 547         case '"':
 548         case '*':
 549             *escptr++ = '*';
 550             *escptr++ = (*strptr == '\n' ? 'N' : *strptr);
 551             break;
 552         default:
 553             *escptr++ = *strptr;
 554             break;
 555         }
 556     }
 557     *escptr++ = '"';
 558     *escptr = '\0';
 559     return escaped;
 560 }
 561
 562 /* Append arg string to argptr increasing argptr if needed */
 563 static char *appendarg(char *argptr, int *argptrsize, const char *arg, APTR pool)
 564 {
 565     while(strlen(argptr) + strlen(arg) + 2 > *argptrsize)
 566     {
 567         char *argptr2;
 568         int argptrsize2 = 2*(*argptrsize);
 569
 570         argptr2 = AllocPooled(pool, argptrsize2);
 571         if(!argptr2)
 572         {
 573             FreePooled(pool, argptr, *argptrsize);
 574             return NULL;
 575         }
 576         strcpy(argptr2, argptr);
 577         FreePooled(pool, argptr, *argptrsize);
 578         argptr = argptr2;
 579         *argptrsize = argptrsize2;
 580     }
 581     strcat(argptr, arg);
 582     strcat(argptr, " ");
 583
 584     return argptr;
 585 }
 586
 587 static char *appendargs(char *argptr, int *argssizeptr, char *const args[], APTR pool)
 588 {
 589     char *const *argsit;
 590
 591     for (argsit = args; *argsit && argptr; argsit++)
 592     {
 593         if(containswhite(*argsit))
 594         {
 595             char *escaped = escape(*argsit);
 596             if(!escaped) {
 597                 return NULL;
 598             }
 599             argptr = appendarg(argptr, argssizeptr, escaped, pool);
 600             free(escaped);
 601         }
 602         else
 603             argptr = appendarg(argptr, argssizeptr, *argsit, pool);
 604     }
 605
 606     return argptr;
 607 }
 608
 609 static void __exec_cleanup(struct aroscbase *aroscbase)
 610 {
 611     D(bug("__exec_cleanup: me(%x)\n", FindTask(NULL)));
 612
 613     if(aroscbase->acb_exec_oldin)
 614     {
 615         SelectInput(aroscbase->acb_exec_oldin);
 616         aroscbase->acb_exec_oldin = (BPTR)NULL;
 617     }
 618     if(aroscbase->acb_exec_oldout)
 619     {
 620         SelectOutput(aroscbase->acb_exec_oldout);
 621         aroscbase->acb_exec_oldout = (BPTR)NULL;
 622     }
 623     if(aroscbase->acb_exec_olderr)
 624     {
 625         struct Process *me = (struct Process *)FindTask(NULL);
 626
 627         me->pr_CES = aroscbase->acb_exec_olderr;
 628         aroscbase->acb_exec_olderr = BNULL;
 629     }
 630
 631     if (aroscbase->acb_exec_pool)
 632     {
 633         DeletePool(aroscbase->acb_exec_pool);
 634         aroscbase->acb_exec_pool = NULL;
 635     }
 636     if (aroscbase->acb_exec_seglist)
 637     {
 638         UnLoadSeg(aroscbase->acb_exec_seglist);
 639         aroscbase->acb_exec_seglist = (BPTR)NULL;
 640     }
 641 }
 642
 643 static void close_on_exec(struct aroscbase *aroscbase)
 644 {
 645     int i;
 646     fdesc *fd;
 647
 648     for (i = __getfdslots() - 1; i >= 0; i--)
 649     {
 650         if ((fd = __getfdesc(i)) != NULL)
 651         {
 652             D(bug("close_on_exec: checking fd %d\n", i));
 653             if (fd->fdflags & FD_CLOEXEC)
 654             {
 655                 D(bug("close_on_exec: closing fd %d\n", i));
 656                 assert(close(i) == 0);
 657             }
 658         }
 659     }
 660 }