editors/awk.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * awk implementation for busybox
   4  *
   5  * Copyright (C) 2002 by Dmitry Zakharov <dmit@crp.bank.gov.ua>
   6  *
   7  * Licensed under the GPL v2 or later, see the file LICENSE in this tarball.
   8  */
   9
  10 #include "libbb.h"
  11 #include "xregex.h"
  12 #include <math.h>
  13
  14 /* This is a NOEXEC applet. Be very careful! */
  15
  16
  17 #define MAXVARFMT       240
  18 #define MINNVBLOCK      64
  19
  20 /* variable flags */
  21 #define VF_NUMBER       0x0001  /* 1 = primary type is number */
  22 #define VF_ARRAY        0x0002  /* 1 = it's an array */
  23
  24 #define VF_CACHED       0x0100  /* 1 = num/str value has cached str/num eq */
  25 #define VF_USER         0x0200  /* 1 = user input (may be numeric string) */
  26 #define VF_SPECIAL      0x0400  /* 1 = requires extra handling when changed */
  27 #define VF_WALK         0x0800  /* 1 = variable has alloc'd x.walker list */
  28 #define VF_FSTR         0x1000  /* 1 = var::string points to fstring buffer */
  29 #define VF_CHILD        0x2000  /* 1 = function arg; x.parent points to source */
  30 #define VF_DIRTY        0x4000  /* 1 = variable was set explicitly */
  31
  32 /* these flags are static, don't change them when value is changed */
  33 #define VF_DONTTOUCH    (VF_ARRAY | VF_SPECIAL | VF_WALK | VF_CHILD | VF_DIRTY)
  34
  35 /* Variable */
  36 typedef struct var_s {
  37         unsigned type;            /* flags */
  38         double number;
  39         char *string;
  40         union {
  41                 int aidx;               /* func arg idx (for compilation stage) */
  42                 struct xhash_s *array;  /* array ptr */
  43                 struct var_s *parent;   /* for func args, ptr to actual parameter */
  44                 char **walker;          /* list of array elements (for..in) */
  45         } x;
  46 } var;
  47
  48 /* Node chain (pattern-action chain, BEGIN, END, function bodies) */
  49 typedef struct chain_s {
  50         struct node_s *first;
  51         struct node_s *last;
  52         const char *programname;
  53 } chain;
  54
  55 /* Function */
  56 typedef struct func_s {
  57         unsigned nargs;
  58         struct chain_s body;
  59 } func;
  60
  61 /* I/O stream */
  62 typedef struct rstream_s {
  63         FILE *F;
  64         char *buffer;
  65         int adv;
  66         int size;
  67         int pos;
  68         smallint is_pipe;
  69 } rstream;
  70
  71 typedef struct hash_item_s {
  72         union {
  73                 struct var_s v;         /* variable/array hash */
  74                 struct rstream_s rs;    /* redirect streams hash */
  75                 struct func_s f;        /* functions hash */
  76         } data;
  77         struct hash_item_s *next;       /* next in chain */
  78         char name[1];                   /* really it's longer */
  79 } hash_item;
  80
  81 typedef struct xhash_s {
  82         unsigned nel;           /* num of elements */
  83         unsigned csize;         /* current hash size */
  84         unsigned nprime;        /* next hash size in PRIMES[] */
  85         unsigned glen;          /* summary length of item names */
  86         struct hash_item_s **items;
  87 } xhash;
  88
  89 /* Tree node */
  90 typedef struct node_s {
  91         uint32_t info;
  92         unsigned lineno;
  93         union {
  94                 struct node_s *n;
  95                 var *v;
  96                 int i;
  97                 char *s;
  98                 regex_t *re;
  99         } l;
 100         union {
 101                 struct node_s *n;
 102                 regex_t *ire;
 103                 func *f;
 104                 int argno;
 105         } r;
 106         union {
 107                 struct node_s *n;
 108         } a;
 109 } node;
 110
 111 /* Block of temporary variables */
 112 typedef struct nvblock_s {
 113         int size;
 114         var *pos;
 115         struct nvblock_s *prev;
 116         struct nvblock_s *next;
 117         var nv[0];
 118 } nvblock;
 119
 120 typedef struct tsplitter_s {
 121         node n;
 122         regex_t re[2];
 123 } tsplitter;
 124
 125 /* simple token classes */
 126 /* Order and hex values are very important!!!  See next_token() */
 127 #define TC_SEQSTART      1                              /* ( */
 128 #define TC_SEQTERM      (1 << 1)                /* ) */
 129 #define TC_REGEXP       (1 << 2)                /* /.../ */
 130 #define TC_OUTRDR       (1 << 3)                /* | > >> */
 131 #define TC_UOPPOST      (1 << 4)                /* unary postfix operator */
 132 #define TC_UOPPRE1      (1 << 5)                /* unary prefix operator */
 133 #define TC_BINOPX       (1 << 6)                /* two-opnd operator */
 134 #define TC_IN           (1 << 7)
 135 #define TC_COMMA        (1 << 8)
 136 #define TC_PIPE         (1 << 9)                /* input redirection pipe */
 137 #define TC_UOPPRE2      (1 << 10)               /* unary prefix operator */
 138 #define TC_ARRTERM      (1 << 11)               /* ] */
 139 #define TC_GRPSTART     (1 << 12)               /* { */
 140 #define TC_GRPTERM      (1 << 13)               /* } */
 141 #define TC_SEMICOL      (1 << 14)
 142 #define TC_NEWLINE      (1 << 15)
 143 #define TC_STATX        (1 << 16)               /* ctl statement (for, next...) */
 144 #define TC_WHILE        (1 << 17)
 145 #define TC_ELSE         (1 << 18)
 146 #define TC_BUILTIN      (1 << 19)
 147 #define TC_GETLINE      (1 << 20)
 148 #define TC_FUNCDECL     (1 << 21)               /* `function' `func' */
 149 #define TC_BEGIN        (1 << 22)
 150 #define TC_END          (1 << 23)
 151 #define TC_EOF          (1 << 24)
 152 #define TC_VARIABLE     (1 << 25)
 153 #define TC_ARRAY        (1 << 26)
 154 #define TC_FUNCTION     (1 << 27)
 155 #define TC_STRING       (1 << 28)
 156 #define TC_NUMBER       (1 << 29)
 157
 158 #define TC_UOPPRE  (TC_UOPPRE1 | TC_UOPPRE2)
 159
 160 /* combined token classes */
 161 #define TC_BINOP   (TC_BINOPX | TC_COMMA | TC_PIPE | TC_IN)
 162 #define TC_UNARYOP (TC_UOPPRE | TC_UOPPOST)
 163 #define TC_OPERAND (TC_VARIABLE | TC_ARRAY | TC_FUNCTION \
 164                    | TC_BUILTIN | TC_GETLINE | TC_SEQSTART | TC_STRING | TC_NUMBER)
 165
 166 #define TC_STATEMNT (TC_STATX | TC_WHILE)
 167 #define TC_OPTERM  (TC_SEMICOL | TC_NEWLINE)
 168
 169 /* word tokens, cannot mean something else if not expected */
 170 #define TC_WORD    (TC_IN | TC_STATEMNT | TC_ELSE | TC_BUILTIN \
 171                    | TC_GETLINE | TC_FUNCDECL | TC_BEGIN | TC_END)
 172
 173 /* discard newlines after these */
 174 #define TC_NOTERM  (TC_COMMA | TC_GRPSTART | TC_GRPTERM \
 175                    | TC_BINOP | TC_OPTERM)
 176
 177 /* what can expression begin with */
 178 #define TC_OPSEQ   (TC_OPERAND | TC_UOPPRE | TC_REGEXP)
 179 /* what can group begin with */
 180 #define TC_GRPSEQ  (TC_OPSEQ | TC_OPTERM | TC_STATEMNT | TC_GRPSTART)
 181
 182 /* if previous token class is CONCAT1 and next is CONCAT2, concatenation */
 183 /* operator is inserted between them */
 184 #define TC_CONCAT1 (TC_VARIABLE | TC_ARRTERM | TC_SEQTERM \
 185                    | TC_STRING | TC_NUMBER | TC_UOPPOST)
 186 #define TC_CONCAT2 (TC_OPERAND | TC_UOPPRE)
 187
 188 #define OF_RES1    0x010000
 189 #define OF_RES2    0x020000
 190 #define OF_STR1    0x040000
 191 #define OF_STR2    0x080000
 192 #define OF_NUM1    0x100000
 193 #define OF_CHECKED 0x200000
 194
 195 /* combined operator flags */
 196 #define xx      0
 197 #define xV      OF_RES2
 198 #define xS      (OF_RES2 | OF_STR2)
 199 #define Vx      OF_RES1
 200 #define VV      (OF_RES1 | OF_RES2)
 201 #define Nx      (OF_RES1 | OF_NUM1)
 202 #define NV      (OF_RES1 | OF_NUM1 | OF_RES2)
 203 #define Sx      (OF_RES1 | OF_STR1)
 204 #define SV      (OF_RES1 | OF_STR1 | OF_RES2)
 205 #define SS      (OF_RES1 | OF_STR1 | OF_RES2 | OF_STR2)
 206
 207 #define OPCLSMASK 0xFF00
 208 #define OPNMASK   0x007F
 209
 210 /* operator priority is a highest byte (even: r->l, odd: l->r grouping)
 211  * For builtins it has different meaning: n n s3 s2 s1 v3 v2 v1,
 212  * n - min. number of args, vN - resolve Nth arg to var, sN - resolve to string
 213  */
 214 #define P(x)      (x << 24)
 215 #define PRIMASK   0x7F000000
 216 #define PRIMASK2  0x7E000000
 217
 218 /* Operation classes */
 219
 220 #define SHIFT_TIL_THIS  0x0600
 221 #define RECUR_FROM_THIS 0x1000
 222
 223 enum {
 224         OC_DELETE = 0x0100,     OC_EXEC = 0x0200,       OC_NEWSOURCE = 0x0300,
 225         OC_PRINT = 0x0400,      OC_PRINTF = 0x0500,     OC_WALKINIT = 0x0600,
 226
 227         OC_BR = 0x0700,         OC_BREAK = 0x0800,      OC_CONTINUE = 0x0900,
 228         OC_EXIT = 0x0a00,       OC_NEXT = 0x0b00,       OC_NEXTFILE = 0x0c00,
 229         OC_TEST = 0x0d00,       OC_WALKNEXT = 0x0e00,
 230
 231         OC_BINARY = 0x1000,     OC_BUILTIN = 0x1100,    OC_COLON = 0x1200,
 232         OC_COMMA = 0x1300,      OC_COMPARE = 0x1400,    OC_CONCAT = 0x1500,
 233         OC_FBLTIN = 0x1600,     OC_FIELD = 0x1700,      OC_FNARG = 0x1800,
 234         OC_FUNC = 0x1900,       OC_GETLINE = 0x1a00,    OC_IN = 0x1b00,
 235         OC_LAND = 0x1c00,       OC_LOR = 0x1d00,        OC_MATCH = 0x1e00,
 236         OC_MOVE = 0x1f00,       OC_PGETLINE = 0x2000,   OC_REGEXP = 0x2100,
 237         OC_REPLACE = 0x2200,    OC_RETURN = 0x2300,     OC_SPRINTF = 0x2400,
 238         OC_TERNARY = 0x2500,    OC_UNARY = 0x2600,      OC_VAR = 0x2700,
 239         OC_DONE = 0x2800,
 240
 241         ST_IF = 0x3000,         ST_DO = 0x3100,         ST_FOR = 0x3200,
 242         ST_WHILE = 0x3300
 243 };
 244
 245 /* simple builtins */
 246 enum {
 247         F_in,   F_rn,   F_co,   F_ex,   F_lg,   F_si,   F_sq,   F_sr,
 248         F_ti,   F_le,   F_sy,   F_ff,   F_cl
 249 };
 250
 251 /* builtins */
 252 enum {
 253         B_a2,   B_ix,   B_ma,   B_sp,   B_ss,   B_ti,   B_lo,   B_up,
 254         B_ge,   B_gs,   B_su,
 255         B_an,   B_co,   B_ls,   B_or,   B_rs,   B_xo,
 256 };
 257
 258 /* tokens and their corresponding info values */
 259
 260 #define NTC     "\377"  /* switch to next token class (tc<<1) */
 261 #define NTCC    '\377'
 262
 263 #define OC_B    OC_BUILTIN
 264
 265 static const char tokenlist[] ALIGN1 =
 266         "\1("       NTC
 267         "\1)"       NTC
 268         "\1/"       NTC                                 /* REGEXP */
 269         "\2>>"      "\1>"       "\1|"       NTC         /* OUTRDR */
 270         "\2++"      "\2--"      NTC                     /* UOPPOST */
 271         "\2++"      "\2--"      "\1$"       NTC         /* UOPPRE1 */
 272         "\2=="      "\1="       "\2+="      "\2-="      /* BINOPX */
 273         "\2*="      "\2/="      "\2%="      "\2^="
 274         "\1+"       "\1-"       "\3**="     "\2**"
 275         "\1/"       "\1%"       "\1^"       "\1*"
 276         "\2!="      "\2>="      "\2<="      "\1>"
 277         "\1<"       "\2!~"      "\1~"       "\2&&"
 278         "\2||"      "\1?"       "\1:"       NTC
 279         "\2in"      NTC
 280         "\1,"       NTC
 281         "\1|"       NTC
 282         "\1+"       "\1-"       "\1!"       NTC         /* UOPPRE2 */
 283         "\1]"       NTC
 284         "\1{"       NTC
 285         "\1}"       NTC
 286         "\1;"       NTC
 287         "\1\n"      NTC
 288         "\2if"      "\2do"      "\3for"     "\5break"   /* STATX */
 289         "\10continue"           "\6delete"  "\5print"
 290         "\6printf"  "\4next"    "\10nextfile"
 291         "\6return"  "\4exit"    NTC
 292         "\5while"   NTC
 293         "\4else"    NTC
 294
 295         "\3and"     "\5compl"   "\6lshift"  "\2or"
 296         "\6rshift"  "\3xor"
 297         "\5close"   "\6system"  "\6fflush"  "\5atan2"   /* BUILTIN */
 298         "\3cos"     "\3exp"     "\3int"     "\3log"
 299         "\4rand"    "\3sin"     "\4sqrt"    "\5srand"
 300         "\6gensub"  "\4gsub"    "\5index"   "\6length"
 301         "\5match"   "\5split"   "\7sprintf" "\3sub"
 302         "\6substr"  "\7systime" "\10strftime"
 303         "\7tolower" "\7toupper" NTC
 304         "\7getline" NTC
 305         "\4func"    "\10function"   NTC
 306         "\5BEGIN"   NTC
 307         "\3END"     "\0"
 308         ;
 309
 310 static const uint32_t tokeninfo[] = {
 311         0,
 312         0,
 313         OC_REGEXP,
 314         xS|'a',     xS|'w',     xS|'|',
 315         OC_UNARY|xV|P(9)|'p',       OC_UNARY|xV|P(9)|'m',
 316         OC_UNARY|xV|P(9)|'P',       OC_UNARY|xV|P(9)|'M',
 317             OC_FIELD|xV|P(5),
 318         OC_COMPARE|VV|P(39)|5,      OC_MOVE|VV|P(74),
 319             OC_REPLACE|NV|P(74)|'+',    OC_REPLACE|NV|P(74)|'-',
 320         OC_REPLACE|NV|P(74)|'*',    OC_REPLACE|NV|P(74)|'/',
 321             OC_REPLACE|NV|P(74)|'%',    OC_REPLACE|NV|P(74)|'&',
 322         OC_BINARY|NV|P(29)|'+',     OC_BINARY|NV|P(29)|'-',
 323             OC_REPLACE|NV|P(74)|'&',    OC_BINARY|NV|P(15)|'&',
 324         OC_BINARY|NV|P(25)|'/',     OC_BINARY|NV|P(25)|'%',
 325             OC_BINARY|NV|P(15)|'&',     OC_BINARY|NV|P(25)|'*',
 326         OC_COMPARE|VV|P(39)|4,      OC_COMPARE|VV|P(39)|3,
 327             OC_COMPARE|VV|P(39)|0,      OC_COMPARE|VV|P(39)|1,
 328         OC_COMPARE|VV|P(39)|2,      OC_MATCH|Sx|P(45)|'!',
 329             OC_MATCH|Sx|P(45)|'~',      OC_LAND|Vx|P(55),
 330         OC_LOR|Vx|P(59),            OC_TERNARY|Vx|P(64)|'?',
 331             OC_COLON|xx|P(67)|':',
 332         OC_IN|SV|P(49),
 333         OC_COMMA|SS|P(80),
 334         OC_PGETLINE|SV|P(37),
 335         OC_UNARY|xV|P(19)|'+',      OC_UNARY|xV|P(19)|'-',
 336             OC_UNARY|xV|P(19)|'!',
 337         0,
 338         0,
 339         0,
 340         0,
 341         0,
 342         ST_IF,          ST_DO,          ST_FOR,         OC_BREAK,
 343         OC_CONTINUE,                    OC_DELETE|Vx,   OC_PRINT,
 344         OC_PRINTF,      OC_NEXT,        OC_NEXTFILE,
 345         OC_RETURN|Vx,   OC_EXIT|Nx,
 346         ST_WHILE,
 347         0,
 348
 349         OC_B|B_an|P(0x83), OC_B|B_co|P(0x41), OC_B|B_ls|P(0x83), OC_B|B_or|P(0x83),
 350         OC_B|B_rs|P(0x83), OC_B|B_xo|P(0x83),
 351         OC_FBLTIN|Sx|F_cl, OC_FBLTIN|Sx|F_sy, OC_FBLTIN|Sx|F_ff, OC_B|B_a2|P(0x83),
 352         OC_FBLTIN|Nx|F_co, OC_FBLTIN|Nx|F_ex, OC_FBLTIN|Nx|F_in, OC_FBLTIN|Nx|F_lg,
 353         OC_FBLTIN|F_rn,    OC_FBLTIN|Nx|F_si, OC_FBLTIN|Nx|F_sq, OC_FBLTIN|Nx|F_sr,
 354         OC_B|B_ge|P(0xd6), OC_B|B_gs|P(0xb6), OC_B|B_ix|P(0x9b), OC_FBLTIN|Sx|F_le,
 355         OC_B|B_ma|P(0x89), OC_B|B_sp|P(0x8b), OC_SPRINTF,        OC_B|B_su|P(0xb6),
 356         OC_B|B_ss|P(0x8f), OC_FBLTIN|F_ti,    OC_B|B_ti|P(0x0b),
 357         OC_B|B_lo|P(0x49), OC_B|B_up|P(0x49),
 358         OC_GETLINE|SV|P(0),
 359         0,      0,
 360         0,
 361         0
 362 };
 363
 364 /* internal variable names and their initial values       */
 365 /* asterisk marks SPECIAL vars; $ is just no-named Field0 */
 366 enum {
 367         CONVFMT,    OFMT,       FS,         OFS,
 368         ORS,        RS,         RT,         FILENAME,
 369         SUBSEP,     ARGIND,     ARGC,       ARGV,
 370         ERRNO,      FNR,
 371         NR,         NF,         IGNORECASE,
 372         ENVIRON,    F0,         NUM_INTERNAL_VARS
 373 };
 374
 375 static const char vNames[] ALIGN1 =
 376         "CONVFMT\0" "OFMT\0"    "FS\0*"     "OFS\0"
 377         "ORS\0"     "RS\0*"     "RT\0"      "FILENAME\0"
 378         "SUBSEP\0"  "ARGIND\0"  "ARGC\0"    "ARGV\0"
 379         "ERRNO\0"   "FNR\0"
 380         "NR\0"      "NF\0*"     "IGNORECASE\0*"
 381         "ENVIRON\0" "$\0*"      "\0";
 382
 383 static const char vValues[] ALIGN1 =
 384         "%.6g\0"    "%.6g\0"    " \0"       " \0"
 385         "\n\0"      "\n\0"      "\0"        "\0"
 386         "\034\0"
 387         "\377";
 388
 389 /* hash size may grow to these values */
 390 #define FIRST_PRIME 61
 391 static const uint16_t PRIMES[] ALIGN2 = { 251, 1021, 4093, 16381, 65521 };
 392
 393
 394 /* Globals. Split in two parts so that first one is addressed
 395  * with (mostly short) negative offsets */
 396 struct globals {
 397         chain beginseq, mainseq, endseq;
 398         chain *seq;
 399         node *break_ptr, *continue_ptr;
 400         rstream *iF;
 401         xhash *vhash, *ahash, *fdhash, *fnhash;
 402         const char *g_progname;
 403         int g_lineno;
 404         int nfields;
 405         int maxfields; /* used in fsrealloc() only */
 406         var *Fields;
 407         nvblock *g_cb;
 408         char *g_pos;
 409         char *g_buf;
 410         smallint icase;
 411         smallint exiting;
 412         smallint nextrec;
 413         smallint nextfile;
 414         smallint is_f0_split;
 415 };
 416 struct globals2 {
 417         uint32_t t_info; /* often used */
 418         uint32_t t_tclass;
 419         char *t_string;
 420         int t_lineno;
 421         int t_rollback;
 422
 423         var *intvar[NUM_INTERNAL_VARS]; /* often used */
 424
 425         /* former statics from various functions */
 426         char *split_f0__fstrings;
 427
 428         uint32_t next_token__save_tclass;
 429         uint32_t next_token__save_info;
 430         uint32_t next_token__ltclass;
 431         smallint next_token__concat_inserted;
 432
 433         smallint next_input_file__files_happen;
 434         rstream next_input_file__rsm;
 435
 436         var *evaluate__fnargs;
 437         unsigned evaluate__seed;
 438         regex_t evaluate__sreg;
 439
 440         var ptest__v;
 441
 442         tsplitter exec_builtin__tspl;
 443
 444         /* biggest and least used members go last */
 445         double t_double;
 446         tsplitter fsplitter, rsplitter;
 447 };
 448 #define G1 (ptr_to_globals[-1])
 449 #define G (*(struct globals2 *)ptr_to_globals)
 450 /* For debug. nm --size-sort awk.o | grep -vi ' [tr] ' */
 451 /* char G1size[sizeof(G1)]; - 0x6c */
 452 /* char Gsize[sizeof(G)]; - 0x1cc */
 453 /* Trying to keep most of members accessible with short offsets: */
 454 /* char Gofs_seed[offsetof(struct globals2, evaluate__seed)]; - 0x90 */
 455 #define beginseq     (G1.beginseq    )
 456 #define mainseq      (G1.mainseq     )
 457 #define endseq       (G1.endseq      )
 458 #define seq          (G1.seq         )
 459 #define break_ptr    (G1.break_ptr   )
 460 #define continue_ptr (G1.continue_ptr)
 461 #define iF           (G1.iF          )
 462 #define vhash        (G1.vhash       )
 463 #define ahash        (G1.ahash       )
 464 #define fdhash       (G1.fdhash      )
 465 #define fnhash       (G1.fnhash      )
 466 #define g_progname   (G1.g_progname  )
 467 #define g_lineno     (G1.g_lineno    )
 468 #define nfields      (G1.nfields     )
 469 #define maxfields    (G1.maxfields   )
 470 #define Fields       (G1.Fields      )
 471 #define g_cb         (G1.g_cb        )
 472 #define g_pos        (G1.g_pos       )
 473 #define g_buf        (G1.g_buf       )
 474 #define icase        (G1.icase       )
 475 #define exiting      (G1.exiting     )
 476 #define nextrec      (G1.nextrec     )
 477 #define nextfile     (G1.nextfile    )
 478 #define is_f0_split  (G1.is_f0_split )
 479 #define t_info       (G.t_info      )
 480 #define t_tclass     (G.t_tclass    )
 481 #define t_string     (G.t_string    )
 482 #define t_double     (G.t_double    )
 483 #define t_lineno     (G.t_lineno    )
 484 #define t_rollback   (G.t_rollback  )
 485 #define intvar       (G.intvar      )
 486 #define fsplitter    (G.fsplitter   )
 487 #define rsplitter    (G.rsplitter   )
 488 #define INIT_G() do { \
 489         SET_PTR_TO_GLOBALS(xzalloc(sizeof(G1) + sizeof(G)) + sizeof(G1)); \
 490         G.next_token__ltclass = TC_OPTERM; \
 491         G.evaluate__seed = 1; \
 492 } while (0)
 493
 494
 495 /* function prototypes */
 496 static void handle_special(var *);
 497 static node *parse_expr(uint32_t);
 498 static void chain_group(void);
 499 static var *evaluate(node *, var *);
 500 static rstream *next_input_file(void);
 501 static int fmt_num(char *, int, const char *, double, int);
 502 static int awk_exit(int) NORETURN;
 503
 504 /* ---- error handling ---- */
 505
 506 static const char EMSG_INTERNAL_ERROR[] ALIGN1 = "Internal error";
 507 static const char EMSG_UNEXP_EOS[] ALIGN1 = "Unexpected end of string";
 508 static const char EMSG_UNEXP_TOKEN[] ALIGN1 = "Unexpected token";
 509 static const char EMSG_DIV_BY_ZERO[] ALIGN1 = "Division by zero";
 510 static const char EMSG_INV_FMT[] ALIGN1 = "Invalid format specifier";
 511 static const char EMSG_TOO_FEW_ARGS[] ALIGN1 = "Too few arguments for builtin";
 512 static const char EMSG_NOT_ARRAY[] ALIGN1 = "Not an array";
 513 static const char EMSG_POSSIBLE_ERROR[] ALIGN1 = "Possible syntax error";
 514 static const char EMSG_UNDEF_FUNC[] ALIGN1 = "Call to undefined function";
 515 #if !ENABLE_FEATURE_AWK_MATH
 516 static const char EMSG_NO_MATH[] ALIGN1 = "Math support is not compiled in";
 517 #endif
 518
 519 static void zero_out_var(var * vp)
 520 {
 521         memset(vp, 0, sizeof(*vp));
 522 }
 523
 524 static void syntax_error(const char *const message) NORETURN;
 525 static void syntax_error(const char *const message)
 526 {
 527         bb_error_msg_and_die("%s:%i: %s", g_progname, g_lineno, message);
 528 }
 529
 530 /* ---- hash stuff ---- */
 531
 532 static unsigned hashidx(const char *name)
 533 {
 534         unsigned idx = 0;
 535
 536         while (*name) idx = *name++ + (idx << 6) - idx;
 537         return idx;
 538 }
 539
 540 /* create new hash */
 541 static xhash *hash_init(void)
 542 {
 543         xhash *newhash;
 544
 545         newhash = xzalloc(sizeof(xhash));
 546         newhash->csize = FIRST_PRIME;
 547         newhash->items = xzalloc(newhash->csize * sizeof(hash_item *));
 548
 549         return newhash;
 550 }
 551
 552 /* find item in hash, return ptr to data, NULL if not found */
 553 static void *hash_search(xhash *hash, const char *name)
 554 {
 555         hash_item *hi;
 556
 557         hi = hash->items [ hashidx(name) % hash->csize ];
 558         while (hi) {
 559                 if (strcmp(hi->name, name) == 0)
 560                         return &(hi->data);
 561                 hi = hi->next;
 562         }
 563         return NULL;
 564 }
 565
 566 /* grow hash if it becomes too big */
 567 static void hash_rebuild(xhash *hash)
 568 {
 569         unsigned newsize, i, idx;
 570         hash_item **newitems, *hi, *thi;
 571
 572         if (hash->nprime == ARRAY_SIZE(PRIMES))
 573                 return;
 574
 575         newsize = PRIMES[hash->nprime++];
 576         newitems = xzalloc(newsize * sizeof(hash_item *));
 577
 578         for (i = 0; i < hash->csize; i++) {
 579                 hi = hash->items[i];
 580                 while (hi) {
 581                         thi = hi;
 582                         hi = thi->next;
 583                         idx = hashidx(thi->name) % newsize;
 584                         thi->next = newitems[idx];
 585                         newitems[idx] = thi;
 586                 }
 587         }
 588
 589         free(hash->items);
 590         hash->csize = newsize;
 591         hash->items = newitems;
 592 }
 593
 594 /* find item in hash, add it if necessary. Return ptr to data */
 595 static void *hash_find(xhash *hash, const char *name)
 596 {
 597         hash_item *hi;
 598         unsigned idx;
 599         int l;
 600
 601         hi = hash_search(hash, name);
 602         if (!hi) {
 603                 if (++hash->nel / hash->csize > 10)
 604                         hash_rebuild(hash);
 605
 606                 l = strlen(name) + 1;
 607                 hi = xzalloc(sizeof(hash_item) + l);
 608                 memcpy(hi->name, name, l);
 609
 610                 idx = hashidx(name) % hash->csize;
 611                 hi->next = hash->items[idx];
 612                 hash->items[idx] = hi;
 613                 hash->glen += l;
 614         }
 615         return &(hi->data);
 616 }
 617
 618 #define findvar(hash, name) ((var*)    hash_find((hash), (name)))
 619 #define newvar(name)        ((var*)    hash_find(vhash, (name)))
 620 #define newfile(name)       ((rstream*)hash_find(fdhash, (name)))
 621 #define newfunc(name)       ((func*)   hash_find(fnhash, (name)))
 622
 623 static void hash_remove(xhash *hash, const char *name)
 624 {
 625         hash_item *hi, **phi;
 626
 627         phi = &(hash->items[hashidx(name) % hash->csize]);
 628         while (*phi) {
 629                 hi = *phi;
 630                 if (strcmp(hi->name, name) == 0) {
 631                         hash->glen -= (strlen(name) + 1);
 632                         hash->nel--;
 633                         *phi = hi->next;
 634                         free(hi);
 635                         break;
 636                 }
 637                 phi = &(hi->next);
 638         }
 639 }
 640
 641 /* ------ some useful functions ------ */
 642
 643 static void skip_spaces(char **s)
 644 {
 645         char *p = *s;
 646
 647         while (1) {
 648                 if (*p == '\\' && p[1] == '\n') {
 649                         p++;
 650                         t_lineno++;
 651                 } else if (*p != ' ' && *p != '\t') {
 652                         break;
 653                 }
 654                 p++;
 655         }
 656         *s = p;
 657 }
 658
 659 static char *nextword(char **s)
 660 {
 661         char *p = *s;
 662
 663         while (*(*s)++) /* */;
 664
 665         return p;
 666 }
 667
 668 static char nextchar(char **s)
 669 {
 670         char c, *pps;
 671
 672         c = *((*s)++);
 673         pps = *s;
 674         if (c == '\\') c = bb_process_escape_sequence((const char**)s);
 675         if (c == '\\' && *s == pps) c = *((*s)++);
 676         return c;
 677 }
 678
 679 static ALWAYS_INLINE int isalnum_(int c)
 680 {
 681         return (isalnum(c) || c == '_');
 682 }
 683
 684 static double my_strtod(char **pp)
 685 {
 686 #if ENABLE_DESKTOP
 687         if ((*pp)[0] == '0'
 688          && ((((*pp)[1] | 0x20) == 'x') || isdigit((*pp)[1]))
 689         ) {
 690                 return strtoull(*pp, pp, 0);
 691         }
 692 #endif
 693         return strtod(*pp, pp);
 694 }
 695
 696 /* -------- working with variables (set/get/copy/etc) -------- */
 697
 698 static xhash *iamarray(var *v)
 699 {
 700         var *a = v;
 701
 702         while (a->type & VF_CHILD)
 703                 a = a->x.parent;
 704
 705         if (!(a->type & VF_ARRAY)) {
 706                 a->type |= VF_ARRAY;
 707                 a->x.array = hash_init();
 708         }
 709         return a->x.array;
 710 }
 711
 712 static void clear_array(xhash *array)
 713 {
 714         unsigned i;
 715         hash_item *hi, *thi;
 716
 717         for (i = 0; i < array->csize; i++) {
 718                 hi = array->items[i];
 719                 while (hi) {
 720                         thi = hi;
 721                         hi = hi->next;
 722                         free(thi->data.v.string);
 723                         free(thi);
 724                 }
 725                 array->items[i] = NULL;
 726         }
 727         array->glen = array->nel = 0;
 728 }
 729
 730 /* clear a variable */
 731 static var *clrvar(var *v)
 732 {
 733         if (!(v->type & VF_FSTR))
 734                 free(v->string);
 735
 736         v->type &= VF_DONTTOUCH;
 737         v->type |= VF_DIRTY;
 738         v->string = NULL;
 739         return v;
 740 }
 741
 742 /* assign string value to variable */
 743 static var *setvar_p(var *v, char *value)
 744 {
 745         clrvar(v);
 746         v->string = value;
 747         handle_special(v);
 748         return v;
 749 }
 750
 751 /* same as setvar_p but make a copy of string */
 752 static var *setvar_s(var *v, const char *value)
 753 {
 754         return setvar_p(v, (value && *value) ? xstrdup(value) : NULL);
 755 }
 756
 757 /* same as setvar_s but set USER flag */
 758 static var *setvar_u(var *v, const char *value)
 759 {
 760         setvar_s(v, value);
 761         v->type |= VF_USER;
 762         return v;
 763 }
 764
 765 /* set array element to user string */
 766 static void setari_u(var *a, int idx, const char *s)
 767 {
 768         char sidx[sizeof(int)*3 + 1];
 769         var *v;
 770
 771         sprintf(sidx, "%d", idx);
 772         v = findvar(iamarray(a), sidx);
 773         setvar_u(v, s);
 774 }
 775
 776 /* assign numeric value to variable */
 777 static var *setvar_i(var *v, double value)
 778 {
 779         clrvar(v);
 780         v->type |= VF_NUMBER;
 781         v->number = value;
 782         handle_special(v);
 783         return v;
 784 }
 785
 786 static const char *getvar_s(var *v)
 787 {
 788         /* if v is numeric and has no cached string, convert it to string */
 789         if ((v->type & (VF_NUMBER | VF_CACHED)) == VF_NUMBER) {
 790                 fmt_num(g_buf, MAXVARFMT, getvar_s(intvar[CONVFMT]), v->number, TRUE);
 791                 v->string = xstrdup(g_buf);
 792                 v->type |= VF_CACHED;
 793         }
 794         return (v->string == NULL) ? "" : v->string;
 795 }
 796
 797 static double getvar_i(var *v)
 798 {
 799         char *s;
 800
 801         if ((v->type & (VF_NUMBER | VF_CACHED)) == 0) {
 802                 v->number = 0;
 803                 s = v->string;
 804                 if (s && *s) {
 805                         v->number = my_strtod(&s);
 806                         if (v->type & VF_USER) {
 807                                 skip_spaces(&s);
 808                                 if (*s != '\0')
 809                                         v->type &= ~VF_USER;
 810                         }
 811                 } else {
 812                         v->type &= ~VF_USER;
 813                 }
 814                 v->type |= VF_CACHED;
 815         }
 816         return v->number;
 817 }
 818
 819 /* Used for operands of bitwise ops */
 820 static unsigned long getvar_i_int(var *v)
 821 {
 822         double d = getvar_i(v);
 823
 824         /* Casting doubles to longs is undefined for values outside
 825          * of target type range. Try to widen it as much as possible */
 826         if (d >= 0)
 827                 return (unsigned long)d;
 828         /* Why? Think about d == -4294967295.0 (assuming 32bit longs) */
 829         return - (long) (unsigned long) (-d);
 830 }
 831
 832 static var *copyvar(var *dest, const var *src)
 833 {
 834         if (dest != src) {
 835                 clrvar(dest);
 836                 dest->type |= (src->type & ~(VF_DONTTOUCH | VF_FSTR));
 837                 dest->number = src->number;
 838                 if (src->string)
 839                         dest->string = xstrdup(src->string);
 840         }
 841         handle_special(dest);
 842         return dest;
 843 }
 844
 845 static var *incvar(var *v)
 846 {
 847         return setvar_i(v, getvar_i(v) + 1.);
 848 }
 849
 850 /* return true if v is number or numeric string */
 851 static int is_numeric(var *v)
 852 {
 853         getvar_i(v);
 854         return ((v->type ^ VF_DIRTY) & (VF_NUMBER | VF_USER | VF_DIRTY));
 855 }
 856
 857 /* return 1 when value of v corresponds to true, 0 otherwise */
 858 static int istrue(var *v)
 859 {
 860         if (is_numeric(v))
 861                 return (v->number == 0) ? 0 : 1;
 862         return (v->string && *(v->string)) ? 1 : 0;
 863 }
 864
 865 /* temporary variables allocator. Last allocated should be first freed */
 866 static var *nvalloc(int n)
 867 {
 868         nvblock *pb = NULL;
 869         var *v, *r;
 870         int size;
 871
 872         while (g_cb) {
 873                 pb = g_cb;
 874                 if ((g_cb->pos - g_cb->nv) + n <= g_cb->size) break;
 875                 g_cb = g_cb->next;
 876         }
 877
 878         if (!g_cb) {
 879                 size = (n <= MINNVBLOCK) ? MINNVBLOCK : n;
 880                 g_cb = xzalloc(sizeof(nvblock) + size * sizeof(var));
 881                 g_cb->size = size;
 882                 g_cb->pos = g_cb->nv;
 883                 g_cb->prev = pb;
 884                 /*g_cb->next = NULL; - xzalloc did it */
 885                 if (pb) pb->next = g_cb;
 886         }
 887
 888         v = r = g_cb->pos;
 889         g_cb->pos += n;
 890
 891         while (v < g_cb->pos) {
 892                 v->type = 0;
 893                 v->string = NULL;
 894                 v++;
 895         }
 896
 897         return r;
 898 }
 899
 900 static void nvfree(var *v)
 901 {
 902         var *p;
 903
 904         if (v < g_cb->nv || v >= g_cb->pos)
 905                 syntax_error(EMSG_INTERNAL_ERROR);
 906
 907         for (p = v; p < g_cb->pos; p++) {
 908                 if ((p->type & (VF_ARRAY | VF_CHILD)) == VF_ARRAY) {
 909                         clear_array(iamarray(p));
 910                         free(p->x.array->items);
 911                         free(p->x.array);
 912                 }
 913                 if (p->type & VF_WALK)
 914                         free(p->x.walker);
 915
 916                 clrvar(p);
 917         }
 918
 919         g_cb->pos = v;
 920         while (g_cb->prev && g_cb->pos == g_cb->nv) {
 921                 g_cb = g_cb->prev;
 922         }
 923 }
 924
 925 /* ------- awk program text parsing ------- */
 926
 927 /* Parse next token pointed by global pos, place results into global ttt.
 928  * If token isn't expected, give away. Return token class
 929  */
 930 static uint32_t next_token(uint32_t expected)
 931 {
 932 #define concat_inserted (G.next_token__concat_inserted)
 933 #define save_tclass     (G.next_token__save_tclass)
 934 #define save_info       (G.next_token__save_info)
 935 /* Initialized to TC_OPTERM: */
 936 #define ltclass         (G.next_token__ltclass)
 937
 938         char *p, *pp, *s;
 939         const char *tl;
 940         uint32_t tc;
 941         const uint32_t *ti;
 942         int l;
 943
 944         if (t_rollback) {
 945                 t_rollback = FALSE;
 946
 947         } else if (concat_inserted) {
 948                 concat_inserted = FALSE;
 949                 t_tclass = save_tclass;
 950                 t_info = save_info;
 951
 952         } else {
 953                 p = g_pos;
 954  readnext:
 955                 skip_spaces(&p);
 956                 g_lineno = t_lineno;
 957                 if (*p == '#')
 958                         while (*p != '\n' && *p != '\0')
 959                                 p++;
 960
 961                 if (*p == '\n')
 962                         t_lineno++;
 963
 964                 if (*p == '\0') {
 965                         tc = TC_EOF;
 966
 967                 } else if (*p == '\"') {
 968                         /* it's a string */
 969                         t_string = s = ++p;
 970                         while (*p != '\"') {
 971                                 if (*p == '\0' || *p == '\n')
 972                                         syntax_error(EMSG_UNEXP_EOS);
 973                                 *(s++) = nextchar(&p);
 974                         }
 975                         p++;
 976                         *s = '\0';
 977                         tc = TC_STRING;
 978
 979                 } else if ((expected & TC_REGEXP) && *p == '/') {
 980                         /* it's regexp */
 981                         t_string = s = ++p;
 982                         while (*p != '/') {
 983                                 if (*p == '\0' || *p == '\n')
 984                                         syntax_error(EMSG_UNEXP_EOS);
 985                                 *s = *p++;
 986                                 if (*s++ == '\\') {
 987                                         pp = p;
 988                                         *(s-1) = bb_process_escape_sequence((const char **)&p);
 989                                         if (*pp == '\\')
 990                                                 *s++ = '\\';
 991                                         if (p == pp)
 992                                                 *s++ = *p++;
 993                                 }
 994                         }
 995                         p++;
 996                         *s = '\0';
 997                         tc = TC_REGEXP;
 998
 999                 } else if (*p == '.' || isdigit(*p)) {
1000                         /* it's a number */
1001                         t_double = my_strtod(&p);
1002                         if (*p == '.')
1003                                 syntax_error(EMSG_UNEXP_TOKEN);
1004                         tc = TC_NUMBER;
1005
1006                 } else {
1007                         /* search for something known */
1008                         tl = tokenlist;
1009                         tc = 0x00000001;
1010                         ti = tokeninfo;
1011                         while (*tl) {
1012                                 l = *(tl++);
1013                                 if (l == NTCC) {
1014                                         tc <<= 1;
1015                                         continue;
1016                                 }
1017                                 /* if token class is expected, token
1018                                  * matches and it's not a longer word,
1019                                  * then this is what we are looking for
1020                                  */
1021                                 if ((tc & (expected | TC_WORD | TC_NEWLINE))
1022                                  && *tl == *p && strncmp(p, tl, l) == 0
1023                                  && !((tc & TC_WORD) && isalnum_(p[l]))
1024                                 ) {
1025                                         t_info = *ti;
1026                                         p += l;
1027                                         break;
1028                                 }
1029                                 ti++;
1030                                 tl += l;
1031                         }
1032
1033                         if (!*tl) {
1034                                 /* it's a name (var/array/function),
1035                                  * otherwise it's something wrong
1036                                  */
1037                                 if (!isalnum_(*p))
1038                                         syntax_error(EMSG_UNEXP_TOKEN);
1039
1040                                 t_string = --p;
1041                                 while (isalnum_(*(++p))) {
1042                                         *(p-1) = *p;
1043                                 }
1044                                 *(p-1) = '\0';
1045                                 tc = TC_VARIABLE;
1046                                 /* also consume whitespace between functionname and bracket */
1047                                 if (!(expected & TC_VARIABLE))
1048                                         skip_spaces(&p);
1049                                 if (*p == '(') {
1050                                         tc = TC_FUNCTION;
1051                                 } else {
1052                                         if (*p == '[') {
1053                                                 p++;
1054                                                 tc = TC_ARRAY;
1055                                         }
1056                                 }
1057                         }
1058                 }
1059                 g_pos = p;
1060
1061                 /* skipping newlines in some cases */
1062                 if ((ltclass & TC_NOTERM) && (tc & TC_NEWLINE))
1063                         goto readnext;
1064
1065                 /* insert concatenation operator when needed */
1066                 if ((ltclass & TC_CONCAT1) && (tc & TC_CONCAT2) && (expected & TC_BINOP)) {
1067                         concat_inserted = TRUE;
1068                         save_tclass = tc;
1069                         save_info = t_info;
1070                         tc = TC_BINOP;
1071                         t_info = OC_CONCAT | SS | P(35);
1072                 }
1073
1074                 t_tclass = tc;
1075         }
1076         ltclass = t_tclass;
1077
1078         /* Are we ready for this? */
1079         if (!(ltclass & expected))
1080                 syntax_error((ltclass & (TC_NEWLINE | TC_EOF)) ?
1081                                 EMSG_UNEXP_EOS : EMSG_UNEXP_TOKEN);
1082
1083         return ltclass;
1084 #undef concat_inserted
1085 #undef save_tclass
1086 #undef save_info
1087 #undef ltclass
1088 }
1089
1090 static void rollback_token(void)
1091 {
1092         t_rollback = TRUE;
1093 }
1094
1095 static node *new_node(uint32_t info)
1096 {
1097         node *n;
1098
1099         n = xzalloc(sizeof(node));
1100         n->info = info;
1101         n->lineno = g_lineno;
1102         return n;
1103 }
1104
1105 static node *mk_re_node(const char *s, node *n, regex_t *re)
1106 {
1107         n->info = OC_REGEXP;
1108         n->l.re = re;
1109         n->r.ire = re + 1;
1110         xregcomp(re, s, REG_EXTENDED);
1111         xregcomp(re + 1, s, REG_EXTENDED | REG_ICASE);
1112
1113         return n;
1114 }
1115
1116 static node *condition(void)
1117 {
1118         next_token(TC_SEQSTART);
1119         return parse_expr(TC_SEQTERM);
1120 }
1121
1122 /* parse expression terminated by given argument, return ptr
1123  * to built subtree. Terminator is eaten by parse_expr */
1124 static node *parse_expr(uint32_t iexp)
1125 {
1126         node sn;
1127         node *cn = &sn;
1128         node *vn, *glptr;
1129         uint32_t tc, xtc;
1130         var *v;
1131
1132         sn.info = PRIMASK;
1133         sn.r.n = glptr = NULL;
1134         xtc = TC_OPERAND | TC_UOPPRE | TC_REGEXP | iexp;
1135
1136         while (!((tc = next_token(xtc)) & iexp)) {
1137                 if (glptr && (t_info == (OC_COMPARE | VV | P(39) | 2))) {
1138                         /* input redirection (<) attached to glptr node */
1139                         cn = glptr->l.n = new_node(OC_CONCAT | SS | P(37));
1140                         cn->a.n = glptr;
1141                         xtc = TC_OPERAND | TC_UOPPRE;
1142                         glptr = NULL;
1143
1144                 } else if (tc & (TC_BINOP | TC_UOPPOST)) {
1145                         /* for binary and postfix-unary operators, jump back over
1146                          * previous operators with higher priority */
1147                         vn = cn;
1148                         while ( ((t_info & PRIMASK) > (vn->a.n->info & PRIMASK2))
1149                          || ((t_info == vn->info) && ((t_info & OPCLSMASK) == OC_COLON)) )
1150                                 vn = vn->a.n;
1151                         if ((t_info & OPCLSMASK) == OC_TERNARY)
1152                                 t_info += P(6);
1153                         cn = vn->a.n->r.n = new_node(t_info);
1154                         cn->a.n = vn->a.n;
1155                         if (tc & TC_BINOP) {
1156                                 cn->l.n = vn;
1157                                 xtc = TC_OPERAND | TC_UOPPRE | TC_REGEXP;
1158                                 if ((t_info & OPCLSMASK) == OC_PGETLINE) {
1159                                         /* it's a pipe */
1160                                         next_token(TC_GETLINE);
1161                                         /* give maximum priority to this pipe */
1162                                         cn->info &= ~PRIMASK;
1163                                         xtc = TC_OPERAND | TC_UOPPRE | TC_BINOP | iexp;
1164                                 }
1165                         } else {
1166                                 cn->r.n = vn;
1167                                 xtc = TC_OPERAND | TC_UOPPRE | TC_BINOP | iexp;
1168                         }
1169                         vn->a.n = cn;
1170
1171                 } else {
1172                         /* for operands and prefix-unary operators, attach them
1173                          * to last node */
1174                         vn = cn;
1175                         cn = vn->r.n = new_node(t_info);
1176                         cn->a.n = vn;
1177                         xtc = TC_OPERAND | TC_UOPPRE | TC_REGEXP;
1178                         if (tc & (TC_OPERAND | TC_REGEXP)) {
1179                                 xtc = TC_UOPPRE | TC_UOPPOST | TC_BINOP | TC_OPERAND | iexp;
1180                                 /* one should be very careful with switch on tclass -
1181                                  * only simple tclasses should be used! */
1182                                 switch (tc) {
1183                                 case TC_VARIABLE:
1184                                 case TC_ARRAY:
1185                                         cn->info = OC_VAR;
1186                                         v = hash_search(ahash, t_string);
1187                                         if (v != NULL) {
1188                                                 cn->info = OC_FNARG;
1189                                                 cn->l.i = v->x.aidx;
1190                                         } else {
1191                                                 cn->l.v = newvar(t_string);
1192                                         }
1193                                         if (tc & TC_ARRAY) {
1194                                                 cn->info |= xS;
1195                                                 cn->r.n = parse_expr(TC_ARRTERM);
1196                                         }
1197                                         break;
1198
1199                                 case TC_NUMBER:
1200                                 case TC_STRING:
1201                                         cn->info = OC_VAR;
1202                                         v = cn->l.v = xzalloc(sizeof(var));
1203                                         if (tc & TC_NUMBER)
1204                                                 setvar_i(v, t_double);
1205                                         else
1206                                                 setvar_s(v, t_string);
1207                                         break;
1208
1209                                 case TC_REGEXP:
1210                                         mk_re_node(t_string, cn, xzalloc(sizeof(regex_t)*2));
1211                                         break;
1212
1213                                 case TC_FUNCTION:
1214                                         cn->info = OC_FUNC;
1215                                         cn->r.f = newfunc(t_string);
1216                                         cn->l.n = condition();
1217                                         break;
1218
1219                                 case TC_SEQSTART:
1220                                         cn = vn->r.n = parse_expr(TC_SEQTERM);
1221                                         cn->a.n = vn;
1222                                         break;
1223
1224                                 case TC_GETLINE:
1225                                         glptr = cn;
1226                                         xtc = TC_OPERAND | TC_UOPPRE | TC_BINOP | iexp;
1227                                         break;
1228
1229                                 case TC_BUILTIN:
1230                                         cn->l.n = condition();
1231                                         break;
1232                                 }
1233                         }
1234                 }
1235         }
1236         return sn.r.n;
1237 }
1238
1239 /* add node to chain. Return ptr to alloc'd node */
1240 static node *chain_node(uint32_t info)
1241 {
1242         node *n;
1243
1244         if (!seq->first)
1245                 seq->first = seq->last = new_node(0);
1246
1247         if (seq->programname != g_progname) {
1248                 seq->programname = g_progname;
1249                 n = chain_node(OC_NEWSOURCE);
1250                 n->l.s = xstrdup(g_progname);
1251         }
1252
1253         n = seq->last;
1254         n->info = info;
1255         seq->last = n->a.n = new_node(OC_DONE);
1256
1257         return n;
1258 }
1259
1260 static void chain_expr(uint32_t info)
1261 {
1262         node *n;
1263
1264         n = chain_node(info);
1265         n->l.n = parse_expr(TC_OPTERM | TC_GRPTERM);
1266         if (t_tclass & TC_GRPTERM)
1267                 rollback_token();
1268 }
1269
1270 static node *chain_loop(node *nn)
1271 {
1272         node *n, *n2, *save_brk, *save_cont;
1273
1274         save_brk = break_ptr;
1275         save_cont = continue_ptr;
1276
1277         n = chain_node(OC_BR | Vx);
1278         continue_ptr = new_node(OC_EXEC);
1279         break_ptr = new_node(OC_EXEC);
1280         chain_group();
1281         n2 = chain_node(OC_EXEC | Vx);
1282         n2->l.n = nn;
1283         n2->a.n = n;
1284         continue_ptr->a.n = n2;
1285         break_ptr->a.n = n->r.n = seq->last;
1286
1287         continue_ptr = save_cont;
1288         break_ptr = save_brk;
1289
1290         return n;
1291 }
1292
1293 /* parse group and attach it to chain */
1294 static void chain_group(void)
1295 {
1296         uint32_t c;
1297         node *n, *n2, *n3;
1298
1299         do {
1300                 c = next_token(TC_GRPSEQ);
1301         } while (c & TC_NEWLINE);
1302
1303         if (c & TC_GRPSTART) {
1304                 while (next_token(TC_GRPSEQ | TC_GRPTERM) != TC_GRPTERM) {
1305                         if (t_tclass & TC_NEWLINE) continue;
1306                         rollback_token();
1307                         chain_group();
1308                 }
1309         } else if (c & (TC_OPSEQ | TC_OPTERM)) {
1310                 rollback_token();
1311                 chain_expr(OC_EXEC | Vx);
1312         } else {                                                /* TC_STATEMNT */
1313                 switch (t_info & OPCLSMASK) {
1314                 case ST_IF:
1315                         n = chain_node(OC_BR | Vx);
1316                         n->l.n = condition();
1317                         chain_group();
1318                         n2 = chain_node(OC_EXEC);
1319                         n->r.n = seq->last;
1320                         if (next_token(TC_GRPSEQ | TC_GRPTERM | TC_ELSE) == TC_ELSE) {
1321                                 chain_group();
1322                                 n2->a.n = seq->last;
1323                         } else {
1324                                 rollback_token();
1325                         }
1326                         break;
1327
1328                 case ST_WHILE:
1329                         n2 = condition();
1330                         n = chain_loop(NULL);
1331                         n->l.n = n2;
1332                         break;
1333
1334                 case ST_DO:
1335                         n2 = chain_node(OC_EXEC);
1336                         n = chain_loop(NULL);
1337                         n2->a.n = n->a.n;
1338                         next_token(TC_WHILE);
1339                         n->l.n = condition();
1340                         break;
1341
1342                 case ST_FOR:
1343                         next_token(TC_SEQSTART);
1344                         n2 = parse_expr(TC_SEMICOL | TC_SEQTERM);
1345                         if (t_tclass & TC_SEQTERM) {    /* for-in */
1346                                 if ((n2->info & OPCLSMASK) != OC_IN)
1347                                         syntax_error(EMSG_UNEXP_TOKEN);
1348                                 n = chain_node(OC_WALKINIT | VV);
1349                                 n->l.n = n2->l.n;
1350                                 n->r.n = n2->r.n;
1351                                 n = chain_loop(NULL);
1352                                 n->info = OC_WALKNEXT | Vx;
1353                                 n->l.n = n2->l.n;
1354                         } else {                        /* for (;;) */
1355                                 n = chain_node(OC_EXEC | Vx);
1356                                 n->l.n = n2;
1357                                 n2 = parse_expr(TC_SEMICOL);
1358                                 n3 = parse_expr(TC_SEQTERM);
1359                                 n = chain_loop(n3);
1360                                 n->l.n = n2;
1361                                 if (!n2)
1362                                         n->info = OC_EXEC;
1363                         }
1364                         break;
1365
1366                 case OC_PRINT:
1367                 case OC_PRINTF:
1368                         n = chain_node(t_info);
1369                         n->l.n = parse_expr(TC_OPTERM | TC_OUTRDR | TC_GRPTERM);
1370                         if (t_tclass & TC_OUTRDR) {
1371                                 n->info |= t_info;
1372                                 n->r.n = parse_expr(TC_OPTERM | TC_GRPTERM);
1373                         }
1374                         if (t_tclass & TC_GRPTERM)
1375                                 rollback_token();
1376                         break;
1377
1378                 case OC_BREAK:
1379                         n = chain_node(OC_EXEC);
1380                         n->a.n = break_ptr;
1381                         break;
1382
1383                 case OC_CONTINUE:
1384                         n = chain_node(OC_EXEC);
1385                         n->a.n = continue_ptr;
1386                         break;
1387
1388                 /* delete, next, nextfile, return, exit */
1389                 default:
1390                         chain_expr(t_info);
1391                 }
1392         }
1393 }
1394
1395 static void parse_program(char *p)
1396 {
1397         uint32_t tclass;
1398         node *cn;
1399         func *f;
1400         var *v;
1401
1402         g_pos = p;
1403         t_lineno = 1;
1404         while ((tclass = next_token(TC_EOF | TC_OPSEQ | TC_GRPSTART |
1405                         TC_OPTERM | TC_BEGIN | TC_END | TC_FUNCDECL)) != TC_EOF) {
1406
1407                 if (tclass & TC_OPTERM)
1408                         continue;
1409
1410                 seq = &mainseq;
1411                 if (tclass & TC_BEGIN) {
1412                         seq = &beginseq;
1413                         chain_group();
1414
1415                 } else if (tclass & TC_END) {
1416                         seq = &endseq;
1417                         chain_group();
1418
1419                 } else if (tclass & TC_FUNCDECL) {
1420                         next_token(TC_FUNCTION);
1421                         g_pos++;
1422                         f = newfunc(t_string);
1423                         f->body.first = NULL;
1424                         f->nargs = 0;
1425                         while (next_token(TC_VARIABLE | TC_SEQTERM) & TC_VARIABLE) {
1426                                 v = findvar(ahash, t_string);
1427                                 v->x.aidx = (f->nargs)++;
1428
1429                                 if (next_token(TC_COMMA | TC_SEQTERM) & TC_SEQTERM)
1430                                         break;
1431                         }
1432                         seq = &(f->body);
1433                         chain_group();
1434                         clear_array(ahash);
1435
1436                 } else if (tclass & TC_OPSEQ) {
1437                         rollback_token();
1438                         cn = chain_node(OC_TEST);
1439                         cn->l.n = parse_expr(TC_OPTERM | TC_EOF | TC_GRPSTART);
1440                         if (t_tclass & TC_GRPSTART) {
1441                                 rollback_token();
1442                                 chain_group();
1443                         } else {
1444                                 chain_node(OC_PRINT);
1445                         }
1446                         cn->r.n = mainseq.last;
1447
1448                 } else /* if (tclass & TC_GRPSTART) */ {
1449                         rollback_token();
1450                         chain_group();
1451                 }
1452         }
1453 }
1454
1455
1456 /* -------- program execution part -------- */
1457
1458 static node *mk_splitter(const char *s, tsplitter *spl)
1459 {
1460         regex_t *re, *ire;
1461         node *n;
1462
1463         re = &spl->re[0];
1464         ire = &spl->re[1];
1465         n = &spl->n;
1466         if ((n->info & OPCLSMASK) == OC_REGEXP) {
1467                 regfree(re);
1468                 regfree(ire); // TODO: nuke ire, use re+1?
1469         }
1470         if (strlen(s) > 1) {
1471                 mk_re_node(s, n, re);
1472         } else {
1473                 n->info = (uint32_t) *s;
1474         }
1475
1476         return n;
1477 }
1478
1479 /* use node as a regular expression. Supplied with node ptr and regex_t
1480  * storage space. Return ptr to regex (if result points to preg, it should
1481  * be later regfree'd manually
1482  */
1483 static regex_t *as_regex(node *op, regex_t *preg)
1484 {
1485         var *v;
1486         const char *s;
1487
1488         if ((op->info & OPCLSMASK) == OC_REGEXP) {
1489                 return icase ? op->r.ire : op->l.re;
1490         }
1491         v = nvalloc(1);
1492         s = getvar_s(evaluate(op, v));
1493         xregcomp(preg, s, icase ? REG_EXTENDED | REG_ICASE : REG_EXTENDED);
1494         nvfree(v);
1495         return preg;
1496 }
1497
1498 /* gradually increasing buffer */
1499 static void qrealloc(char **b, int n, int *size)
1500 {
1501         if (!*b || n >= *size) {
1502                 *size = n + (n>>1) + 80;
1503                 *b = xrealloc(*b, *size);
1504         }
1505 }
1506
1507 /* resize field storage space */
1508 static void fsrealloc(int size)
1509 {
1510         int i;
1511
1512         if (size >= maxfields) {
1513                 i = maxfields;
1514                 maxfields = size + 16;
1515                 Fields = xrealloc(Fields, maxfields * sizeof(var));
1516                 for (; i < maxfields; i++) {
1517                         Fields[i].type = VF_SPECIAL;
1518                         Fields[i].string = NULL;
1519                 }
1520         }
1521
1522         if (size < nfields) {
1523                 for (i = size; i < nfields; i++) {
1524                         clrvar(Fields + i);
1525                 }
1526         }
1527         nfields = size;
1528 }
1529
1530 static int awk_split(const char *s, node *spl, char **slist)
1531 {
1532         int l, n = 0;
1533         char c[4];
1534         char *s1;
1535         regmatch_t pmatch[2]; // TODO: why [2]? [1] is enough...
1536
1537         /* in worst case, each char would be a separate field */
1538         *slist = s1 = xzalloc(strlen(s) * 2 + 3);
1539         strcpy(s1, s);
1540
1541         c[0] = c[1] = (char)spl->info;
1542         c[2] = c[3] = '\0';
1543         if (*getvar_s(intvar[RS]) == '\0')
1544                 c[2] = '\n';
1545
1546         if ((spl->info & OPCLSMASK) == OC_REGEXP) {  /* regex split */
1547                 if (!*s)
1548                         return n; /* "": zero fields */
1549                 n++; /* at least one field will be there */
1550                 do {
1551                         l = strcspn(s, c+2); /* len till next NUL or \n */
1552                         if (regexec(icase ? spl->r.ire : spl->l.re, s, 1, pmatch, 0) == 0
1553                          && pmatch[0].rm_so <= l
1554                         ) {
1555                                 l = pmatch[0].rm_so;
1556                                 if (pmatch[0].rm_eo == 0) {
1557                                         l++;
1558                                         pmatch[0].rm_eo++;
1559                                 }
1560                                 n++; /* we saw yet another delimiter */
1561                         } else {
1562                                 pmatch[0].rm_eo = l;
1563                                 if (s[l]) pmatch[0].rm_eo++;
1564                         }
1565                         memcpy(s1, s, l);
1566                         s1[l] = '\0';
1567                         nextword(&s1);
1568                         s += pmatch[0].rm_eo;
1569                 } while (*s);
1570                 return n;
1571         }
1572         if (c[0] == '\0') {  /* null split */
1573                 while (*s) {
1574                         *s1++ = *s++;
1575                         *s1++ = '\0';
1576                         n++;
1577                 }
1578                 return n;
1579         }
1580         if (c[0] != ' ') {  /* single-character split */
1581                 if (icase) {
1582                         c[0] = toupper(c[0]);
1583                         c[1] = tolower(c[1]);
1584                 }
1585                 if (*s1) n++;
1586                 while ((s1 = strpbrk(s1, c))) {
1587                         *s1++ = '\0';
1588                         n++;
1589                 }
1590                 return n;
1591         }
1592         /* space split */
1593         while (*s) {
1594                 s = skip_whitespace(s);
1595                 if (!*s) break;
1596                 n++;
1597                 while (*s && !isspace(*s))
1598                         *s1++ = *s++;
1599                 *s1++ = '\0';
1600         }
1601         return n;
1602 }
1603
1604 static void split_f0(void)
1605 {
1606 /* static char *fstrings; */
1607 #define fstrings (G.split_f0__fstrings)
1608
1609         int i, n;
1610         char *s;
1611
1612         if (is_f0_split)
1613                 return;
1614
1615         is_f0_split = TRUE;
1616         free(fstrings);
1617         fsrealloc(0);
1618         n = awk_split(getvar_s(intvar[F0]), &fsplitter.n, &fstrings);
1619         fsrealloc(n);
1620         s = fstrings;
1621         for (i = 0; i < n; i++) {
1622                 Fields[i].string = nextword(&s);
1623                 Fields[i].type |= (VF_FSTR | VF_USER | VF_DIRTY);
1624         }
1625
1626         /* set NF manually to avoid side effects */
1627         clrvar(intvar[NF]);
1628         intvar[NF]->type = VF_NUMBER | VF_SPECIAL;
1629         intvar[NF]->number = nfields;
1630 #undef fstrings
1631 }
1632
1633 /* perform additional actions when some internal variables changed */
1634 static void handle_special(var *v)
1635 {
1636         int n;
1637         char *b;
1638         const char *sep, *s;
1639         int sl, l, len, i, bsize;
1640
1641         if (!(v->type & VF_SPECIAL))
1642                 return;
1643
1644         if (v == intvar[NF]) {
1645                 n = (int)getvar_i(v);
1646                 fsrealloc(n);
1647
1648                 /* recalculate $0 */
1649                 sep = getvar_s(intvar[OFS]);
1650                 sl = strlen(sep);
1651                 b = NULL;
1652                 len = 0;
1653                 for (i = 0; i < n; i++) {
1654                         s = getvar_s(&Fields[i]);
1655                         l = strlen(s);
1656                         if (b) {
1657                                 memcpy(b+len, sep, sl);
1658                                 len += sl;
1659                         }
1660                         qrealloc(&b, len+l+sl, &bsize);
1661                         memcpy(b+len, s, l);
1662                         len += l;
1663                 }
1664                 if (b)
1665                         b[len] = '\0';
1666                 setvar_p(intvar[F0], b);
1667                 is_f0_split = TRUE;
1668
1669         } else if (v == intvar[F0]) {
1670                 is_f0_split = FALSE;
1671
1672         } else if (v == intvar[FS]) {
1673                 mk_splitter(getvar_s(v), &fsplitter);
1674
1675         } else if (v == intvar[RS]) {
1676                 mk_splitter(getvar_s(v), &rsplitter);
1677
1678         } else if (v == intvar[IGNORECASE]) {
1679                 icase = istrue(v);
1680
1681         } else {                                /* $n */
1682                 n = getvar_i(intvar[NF]);
1683                 setvar_i(intvar[NF], n > v-Fields ? n : v-Fields+1);
1684                 /* right here v is invalid. Just to note... */
1685         }
1686 }
1687
1688 /* step through func/builtin/etc arguments */
1689 static node *nextarg(node **pn)
1690 {
1691         node *n;
1692
1693         n = *pn;
1694         if (n && (n->info & OPCLSMASK) == OC_COMMA) {
1695                 *pn = n->r.n;
1696                 n = n->l.n;
1697         } else {
1698                 *pn = NULL;
1699         }
1700         return n;
1701 }
1702
1703 static void hashwalk_init(var *v, xhash *array)
1704 {
1705         char **w;
1706         hash_item *hi;
1707         unsigned i;
1708
1709         if (v->type & VF_WALK)
1710                 free(v->x.walker);
1711
1712         v->type |= VF_WALK;
1713         w = v->x.walker = xzalloc(2 + 2*sizeof(char *) + array->glen);
1714         w[0] = w[1] = (char *)(w + 2);
1715         for (i = 0; i < array->csize; i++) {
1716                 hi = array->items[i];
1717                 while (hi) {
1718                         strcpy(*w, hi->name);
1719                         nextword(w);
1720                         hi = hi->next;
1721                 }
1722         }
1723 }
1724
1725 static int hashwalk_next(var *v)
1726 {
1727         char **w;
1728
1729         w = v->x.walker;
1730         if (w[1] == w[0])
1731                 return FALSE;
1732
1733         setvar_s(v, nextword(w+1));
1734         return TRUE;
1735 }
1736
1737 /* evaluate node, return 1 when result is true, 0 otherwise */
1738 static int ptest(node *pattern)
1739 {
1740         /* ptest__v is "static": to save stack space? */
1741         return istrue(evaluate(pattern, &G.ptest__v));
1742 }
1743
1744 /* read next record from stream rsm into a variable v */
1745 static int awk_getline(rstream *rsm, var *v)
1746 {
1747         char *b;
1748         regmatch_t pmatch[2];
1749         int a, p, pp=0, size;
1750         int fd, so, eo, r, rp;
1751         char c, *m, *s;
1752
1753         /* we're using our own buffer since we need access to accumulating
1754          * characters
1755          */
1756         fd = fileno(rsm->F);
1757         m = rsm->buffer;
1758         a = rsm->adv;
1759         p = rsm->pos;
1760         size = rsm->size;
1761         c = (char) rsplitter.n.info;
1762         rp = 0;
1763
1764         if (!m) qrealloc(&m, 256, &size);
1765         do {
1766                 b = m + a;
1767                 so = eo = p;
1768                 r = 1;
1769                 if (p > 0) {
1770                         if ((rsplitter.n.info & OPCLSMASK) == OC_REGEXP) {
1771                                 if (regexec(icase ? rsplitter.n.r.ire : rsplitter.n.l.re,
1772                                                         b, 1, pmatch, 0) == 0) {
1773                                         so = pmatch[0].rm_so;
1774                                         eo = pmatch[0].rm_eo;
1775                                         if (b[eo] != '\0')
1776                                                 break;
1777                                 }
1778                         } else if (c != '\0') {
1779                                 s = strchr(b+pp, c);
1780                                 if (!s) s = memchr(b+pp, '\0', p - pp);
1781                                 if (s) {
1782                                         so = eo = s-b;
1783                                         eo++;
1784                                         break;
1785                                 }
1786                         } else {
1787                                 while (b[rp] == '\n')
1788                                         rp++;
1789                                 s = strstr(b+rp, "\n\n");
1790                                 if (s) {
1791                                         so = eo = s-b;
1792                                         while (b[eo] == '\n') eo++;
1793                                         if (b[eo] != '\0')
1794                                                 break;
1795                                 }
1796                         }
1797                 }
1798
1799                 if (a > 0) {
1800                         memmove(m, (const void *)(m+a), p+1);
1801                         b = m;
1802                         a = 0;
1803                 }
1804
1805                 qrealloc(&m, a+p+128, &size);
1806                 b = m + a;
1807                 pp = p;
1808                 p += safe_read(fd, b+p, size-p-1);
1809                 if (p < pp) {
1810                         p = 0;
1811                         r = 0;
1812                         setvar_i(intvar[ERRNO], errno);
1813                 }
1814                 b[p] = '\0';
1815
1816         } while (p > pp);
1817
1818         if (p == 0) {
1819                 r--;
1820         } else {
1821                 c = b[so]; b[so] = '\0';
1822                 setvar_s(v, b+rp);
1823                 v->type |= VF_USER;
1824                 b[so] = c;
1825                 c = b[eo]; b[eo] = '\0';
1826                 setvar_s(intvar[RT], b+so);
1827                 b[eo] = c;
1828         }
1829
1830         rsm->buffer = m;
1831         rsm->adv = a + eo;
1832         rsm->pos = p - eo;
1833         rsm->size = size;
1834
1835         return r;
1836 }
1837
1838 static int fmt_num(char *b, int size, const char *format, double n, int int_as_int)
1839 {
1840         int r = 0;
1841         char c;
1842         const char *s = format;
1843
1844         if (int_as_int && n == (int)n) {
1845                 r = snprintf(b, size, "%d", (int)n);
1846         } else {
1847                 do { c = *s; } while (c && *++s);
1848                 if (strchr("diouxX", c)) {
1849                         r = snprintf(b, size, format, (int)n);
1850                 } else if (strchr("eEfgG", c)) {
1851                         r = snprintf(b, size, format, n);
1852                 } else {
1853                         syntax_error(EMSG_INV_FMT);
1854                 }
1855         }
1856         return r;
1857 }
1858
1859
1860 /* formatted output into an allocated buffer, return ptr to buffer */
1861 static char *awk_printf(node *n)
1862 {
1863         char *b = NULL;
1864         char *fmt, *s, *f;
1865         const char *s1;
1866         int i, j, incr, bsize;
1867         char c, c1;
1868         var *v, *arg;
1869
1870         v = nvalloc(1);
1871         fmt = f = xstrdup(getvar_s(evaluate(nextarg(&n), v)));
1872
1873         i = 0;
1874         while (*f) {
1875                 s = f;
1876                 while (*f && (*f != '%' || *(++f) == '%'))
1877                         f++;
1878                 while (*f && !isalpha(*f)) {
1879                         if (*f == '*')
1880                                 syntax_error("%*x formats are not supported");
1881                         f++;
1882                 }
1883
1884                 incr = (f - s) + MAXVARFMT;
1885                 qrealloc(&b, incr + i, &bsize);
1886                 c = *f;
1887                 if (c != '\0') f++;
1888                 c1 = *f;
1889                 *f = '\0';
1890                 arg = evaluate(nextarg(&n), v);
1891
1892                 j = i;
1893                 if (c == 'c' || !c) {
1894                         i += sprintf(b+i, s, is_numeric(arg) ?
1895                                         (char)getvar_i(arg) : *getvar_s(arg));
1896                 } else if (c == 's') {
1897                         s1 = getvar_s(arg);
1898                         qrealloc(&b, incr+i+strlen(s1), &bsize);
1899                         i += sprintf(b+i, s, s1);
1900                 } else {
1901                         i += fmt_num(b+i, incr, s, getvar_i(arg), FALSE);
1902                 }
1903                 *f = c1;
1904
1905                 /* if there was an error while sprintf, return value is negative */
1906                 if (i < j) i = j;
1907         }
1908
1909         b = xrealloc(b, i + 1);
1910         free(fmt);
1911         nvfree(v);
1912         b[i] = '\0';
1913         return b;
1914 }
1915
1916 /* common substitution routine
1917  * replace (nm) substring of (src) that match (n) with (repl), store
1918  * result into (dest), return number of substitutions. If nm=0, replace
1919  * all matches. If src or dst is NULL, use $0. If ex=TRUE, enable
1920  * subexpression matching (\1-\9)
1921  */
1922 static int awk_sub(node *rn, const char *repl, int nm, var *src, var *dest, int ex)
1923 {
1924         char *ds = NULL;
1925         const char *s;
1926         const char *sp;
1927         int c, i, j, di, rl, so, eo, nbs, n, dssize;
1928         regmatch_t pmatch[10];
1929         regex_t sreg, *re;
1930
1931         re = as_regex(rn, &sreg);
1932         if (!src) src = intvar[F0];
1933         if (!dest) dest = intvar[F0];
1934
1935         i = di = 0;
1936         sp = getvar_s(src);
1937         rl = strlen(repl);
1938         while (regexec(re, sp, 10, pmatch, sp==getvar_s(src) ? 0 : REG_NOTBOL) == 0) {
1939                 so = pmatch[0].rm_so;
1940                 eo = pmatch[0].rm_eo;
1941
1942                 qrealloc(&ds, di + eo + rl, &dssize);
1943                 memcpy(ds + di, sp, eo);
1944                 di += eo;
1945                 if (++i >= nm) {
1946                         /* replace */
1947                         di -= (eo - so);
1948                         nbs = 0;
1949                         for (s = repl; *s; s++) {
1950                                 ds[di++] = c = *s;
1951                                 if (c == '\\') {
1952                                         nbs++;
1953                                         continue;
1954                                 }
1955                                 if (c == '&' || (ex && c >= '0' && c <= '9')) {
1956                                         di -= ((nbs + 3) >> 1);
1957                                         j = 0;
1958                                         if (c != '&') {
1959                                                 j = c - '0';
1960                                                 nbs++;
1961                                         }
1962                                         if (nbs % 2) {
1963                                                 ds[di++] = c;
1964                                         } else {
1965                                                 n = pmatch[j].rm_eo - pmatch[j].rm_so;
1966                                                 qrealloc(&ds, di + rl + n, &dssize);
1967                                                 memcpy(ds + di, sp + pmatch[j].rm_so, n);
1968                                                 di += n;
1969                                         }
1970                                 }
1971                                 nbs = 0;
1972                         }
1973                 }
1974
1975                 sp += eo;
1976                 if (i == nm) break;
1977                 if (eo == so) {
1978                         ds[di] = *sp++;
1979                         if (!ds[di++]) break;
1980                 }
1981         }
1982
1983         qrealloc(&ds, di + strlen(sp), &dssize);
1984         strcpy(ds + di, sp);
1985         setvar_p(dest, ds);
1986         if (re == &sreg) regfree(re);
1987         return i;
1988 }
1989
1990 static var *exec_builtin(node *op, var *res)
1991 {
1992 #define tspl (G.exec_builtin__tspl)
1993
1994         int (*to_xxx)(int);
1995         var *tv;
1996         node *an[4];
1997         var *av[4];
1998         const char *as[4];
1999         regmatch_t pmatch[2];
2000         regex_t sreg, *re;
2001         node *spl;
2002         uint32_t isr, info;
2003         int nargs;
2004         time_t tt;
2005         char *s, *s1;
2006         int i, l, ll, n;
2007
2008         tv = nvalloc(4);
2009         isr = info = op->info;
2010         op = op->l.n;
2011
2012         av[2] = av[3] = NULL;
2013         for (i = 0; i < 4 && op; i++) {
2014                 an[i] = nextarg(&op);
2015                 if (isr & 0x09000000) av[i] = evaluate(an[i], &tv[i]);
2016                 if (isr & 0x08000000) as[i] = getvar_s(av[i]);
2017                 isr >>= 1;
2018         }
2019
2020         nargs = i;
2021         if ((uint32_t)nargs < (info >> 30))
2022                 syntax_error(EMSG_TOO_FEW_ARGS);
2023
2024         switch (info & OPNMASK) {
2025
2026         case B_a2:
2027 #if ENABLE_FEATURE_AWK_MATH
2028                 setvar_i(res, atan2(getvar_i(av[i]), getvar_i(av[1])));
2029 #else
2030                 syntax_error(EMSG_NO_MATH);
2031 #endif
2032                 break;
2033
2034         case B_sp:
2035                 if (nargs > 2) {
2036                         spl = (an[2]->info & OPCLSMASK) == OC_REGEXP ?
2037                                 an[2] : mk_splitter(getvar_s(evaluate(an[2], &tv[2])), &tspl);
2038                 } else {
2039                         spl = &fsplitter.n;
2040                 }
2041
2042                 n = awk_split(as[0], spl, &s);
2043                 s1 = s;
2044                 clear_array(iamarray(av[1]));
2045                 for (i = 1; i <= n; i++)
2046                         setari_u(av[1], i, nextword(&s1));
2047                 free(s);
2048                 setvar_i(res, n);
2049                 break;
2050
2051         case B_ss:
2052                 l = strlen(as[0]);
2053                 i = getvar_i(av[1]) - 1;
2054                 if (i > l) i = l;
2055                 if (i < 0) i = 0;
2056                 n = (nargs > 2) ? getvar_i(av[2]) : l-i;
2057                 if (n < 0) n = 0;
2058                 s = xstrndup(as[0]+i, n);
2059                 setvar_p(res, s);
2060                 break;
2061
2062         /* Bitwise ops must assume that operands are unsigned. GNU Awk 3.1.5:
2063          * awk '{ print or(-1,1) }' gives "4.29497e+09", not "-2.xxxe+09" */
2064         case B_an:
2065                 setvar_i(res, getvar_i_int(av[0]) & getvar_i_int(av[1]));
2066                 break;
2067
2068         case B_co:
2069                 setvar_i(res, ~getvar_i_int(av[0]));
2070                 break;
2071
2072         case B_ls:
2073                 setvar_i(res, getvar_i_int(av[0]) << getvar_i_int(av[1]));
2074                 break;
2075
2076         case B_or:
2077                 setvar_i(res, getvar_i_int(av[0]) | getvar_i_int(av[1]));
2078                 break;
2079
2080         case B_rs:
2081                 setvar_i(res, getvar_i_int(av[0]) >> getvar_i_int(av[1]));
2082                 break;
2083
2084         case B_xo:
2085                 setvar_i(res, getvar_i_int(av[0]) ^ getvar_i_int(av[1]));
2086                 break;
2087
2088         case B_lo:
2089                 to_xxx = tolower;
2090                 goto lo_cont;
2091
2092         case B_up:
2093                 to_xxx = toupper;
2094  lo_cont:
2095                 s1 = s = xstrdup(as[0]);
2096                 while (*s1) {
2097                         *s1 = (*to_xxx)(*s1);
2098                         s1++;
2099                 }
2100                 setvar_p(res, s);
2101                 break;
2102
2103         case B_ix:
2104                 n = 0;
2105                 ll = strlen(as[1]);
2106                 l = strlen(as[0]) - ll;
2107                 if (ll > 0 && l >= 0) {
2108                         if (!icase) {
2109                                 s = strstr(as[0], as[1]);
2110                                 if (s) n = (s - as[0]) + 1;
2111                         } else {
2112                                 /* this piece of code is terribly slow and
2113                                  * really should be rewritten
2114                                  */
2115                                 for (i=0; i<=l; i++) {
2116                                         if (strncasecmp(as[0]+i, as[1], ll) == 0) {
2117                                                 n = i+1;
2118                                                 break;
2119                                         }
2120                                 }
2121                         }
2122                 }
2123                 setvar_i(res, n);
2124                 break;
2125
2126         case B_ti:
2127                 if (nargs > 1)
2128                         tt = getvar_i(av[1]);
2129                 else
2130                         time(&tt);
2131                 //s = (nargs > 0) ? as[0] : "%a %b %d %H:%M:%S %Z %Y";
2132                 i = strftime(g_buf, MAXVARFMT,
2133                         ((nargs > 0) ? as[0] : "%a %b %d %H:%M:%S %Z %Y"),
2134                         localtime(&tt));
2135                 g_buf[i] = '\0';
2136                 setvar_s(res, g_buf);
2137                 break;
2138
2139         case B_ma:
2140                 re = as_regex(an[1], &sreg);
2141                 n = regexec(re, as[0], 1, pmatch, 0);
2142                 if (n == 0) {
2143                         pmatch[0].rm_so++;
2144                         pmatch[0].rm_eo++;
2145                 } else {
2146                         pmatch[0].rm_so = 0;
2147                         pmatch[0].rm_eo = -1;
2148                 }
2149                 setvar_i(newvar("RSTART"), pmatch[0].rm_so);
2150                 setvar_i(newvar("RLENGTH"), pmatch[0].rm_eo - pmatch[0].rm_so);
2151                 setvar_i(res, pmatch[0].rm_so);
2152                 if (re == &sreg) regfree(re);
2153                 break;
2154
2155         case B_ge:
2156                 awk_sub(an[0], as[1], getvar_i(av[2]), av[3], res, TRUE);
2157                 break;
2158
2159         case B_gs:
2160                 setvar_i(res, awk_sub(an[0], as[1], 0, av[2], av[2], FALSE));
2161                 break;
2162
2163         case B_su:
2164                 setvar_i(res, awk_sub(an[0], as[1], 1, av[2], av[2], FALSE));
2165                 break;
2166         }
2167
2168         nvfree(tv);
2169         return res;
2170 #undef tspl
2171 }
2172
2173 /*
2174  * Evaluate node - the heart of the program. Supplied with subtree
2175  * and place where to store result. returns ptr to result.
2176  */
2177 #define XC(n) ((n) >> 8)
2178
2179 static var *evaluate(node *op, var *res)
2180 {
2181 /* This procedure is recursive so we should count every byte */
2182 #define fnargs (G.evaluate__fnargs)
2183 /* seed is initialized to 1 */
2184 #define seed   (G.evaluate__seed)
2185 #define sreg   (G.evaluate__sreg)
2186
2187         node *op1;
2188         var *v1;
2189         union {
2190                 var *v;
2191                 const char *s;
2192                 double d;
2193                 int i;
2194         } L, R;
2195         uint32_t opinfo;
2196         int opn;
2197         union {
2198                 char *s;
2199                 rstream *rsm;
2200                 FILE *F;
2201                 var *v;
2202                 regex_t *re;
2203                 uint32_t info;
2204         } X;
2205
2206         if (!op)
2207                 return setvar_s(res, NULL);
2208
2209         v1 = nvalloc(2);
2210
2211         while (op) {
2212                 opinfo = op->info;
2213                 opn = (opinfo & OPNMASK);
2214                 g_lineno = op->lineno;
2215
2216                 /* execute inevitable things */
2217                 op1 = op->l.n;
2218                 if (opinfo & OF_RES1) X.v = L.v = evaluate(op1, v1);
2219                 if (opinfo & OF_RES2) R.v = evaluate(op->r.n, v1+1);
2220                 if (opinfo & OF_STR1) L.s = getvar_s(L.v);
2221                 if (opinfo & OF_STR2) R.s = getvar_s(R.v);
2222                 if (opinfo & OF_NUM1) L.d = getvar_i(L.v);
2223
2224                 switch (XC(opinfo & OPCLSMASK)) {
2225
2226                 /* -- iterative node type -- */
2227
2228                 /* test pattern */
2229                 case XC( OC_TEST ):
2230                         if ((op1->info & OPCLSMASK) == OC_COMMA) {
2231                                 /* it's range pattern */
2232                                 if ((opinfo & OF_CHECKED) || ptest(op1->l.n)) {
2233                                         op->info |= OF_CHECKED;
2234                                         if (ptest(op1->r.n))
2235                                                 op->info &= ~OF_CHECKED;
2236
2237                                         op = op->a.n;
2238                                 } else {
2239                                         op = op->r.n;
2240                                 }
2241                         } else {
2242                                 op = (ptest(op1)) ? op->a.n : op->r.n;
2243                         }
2244                         break;
2245
2246                 /* just evaluate an expression, also used as unconditional jump */
2247                 case XC( OC_EXEC ):
2248                         break;
2249
2250                 /* branch, used in if-else and various loops */
2251                 case XC( OC_BR ):
2252                         op = istrue(L.v) ? op->a.n : op->r.n;
2253                         break;
2254
2255                 /* initialize for-in loop */
2256                 case XC( OC_WALKINIT ):
2257                         hashwalk_init(L.v, iamarray(R.v));
2258                         break;
2259
2260                 /* get next array item */
2261                 case XC( OC_WALKNEXT ):
2262                         op = hashwalk_next(L.v) ? op->a.n : op->r.n;
2263                         break;
2264
2265                 case XC( OC_PRINT ):
2266                 case XC( OC_PRINTF ):
2267                         X.F = stdout;
2268                         if (op->r.n) {
2269                                 X.rsm = newfile(R.s);
2270                                 if (!X.rsm->F) {
2271                                         if (opn == '|') {
2272                                                 X.rsm->F = popen(R.s, "w");
2273                                                 if (X.rsm->F == NULL)
2274                                                         bb_perror_msg_and_die("popen");
2275                                                 X.rsm->is_pipe = 1;
2276                                         } else {
2277                                                 X.rsm->F = xfopen(R.s, opn=='w' ? "w" : "a");
2278                                         }
2279                                 }
2280                                 X.F = X.rsm->F;
2281                         }
2282
2283                         if ((opinfo & OPCLSMASK) == OC_PRINT) {
2284                                 if (!op1) {
2285                                         fputs(getvar_s(intvar[F0]), X.F);
2286                                 } else {
2287                                         while (op1) {
2288                                                 L.v = evaluate(nextarg(&op1), v1);
2289                                                 if (L.v->type & VF_NUMBER) {
2290                                                         fmt_num(g_buf, MAXVARFMT, getvar_s(intvar[OFMT]),
2291                                                                         getvar_i(L.v), TRUE);
2292                                                         fputs(g_buf, X.F);
2293                                                 } else {
2294                                                         fputs(getvar_s(L.v), X.F);
2295                                                 }
2296
2297                                                 if (op1) fputs(getvar_s(intvar[OFS]), X.F);
2298                                         }
2299                                 }
2300                                 fputs(getvar_s(intvar[ORS]), X.F);
2301
2302                         } else {        /* OC_PRINTF */
2303                                 L.s = awk_printf(op1);
2304                                 fputs(L.s, X.F);
2305                                 free((char*)L.s);
2306                         }
2307                         fflush(X.F);
2308                         break;
2309
2310                 case XC( OC_DELETE ):
2311                         X.info = op1->info & OPCLSMASK;
2312                         if (X.info == OC_VAR) {
2313                                 R.v = op1->l.v;
2314                         } else if (X.info == OC_FNARG) {
2315                                 R.v = &fnargs[op1->l.i];
2316                         } else {
2317                                 syntax_error(EMSG_NOT_ARRAY);
2318                         }
2319
2320                         if (op1->r.n) {
2321                                 clrvar(L.v);
2322                                 L.s = getvar_s(evaluate(op1->r.n, v1));
2323                                 hash_remove(iamarray(R.v), L.s);
2324                         } else {
2325                                 clear_array(iamarray(R.v));
2326                         }
2327                         break;
2328
2329                 case XC( OC_NEWSOURCE ):
2330                         g_progname = op->l.s;
2331                         break;
2332
2333                 case XC( OC_RETURN ):
2334                         copyvar(res, L.v);
2335                         break;
2336
2337                 case XC( OC_NEXTFILE ):
2338                         nextfile = TRUE;
2339                 case XC( OC_NEXT ):
2340                         nextrec = TRUE;
2341                 case XC( OC_DONE ):
2342                         clrvar(res);
2343                         break;
2344
2345                 case XC( OC_EXIT ):
2346                         awk_exit(L.d);
2347
2348                 /* -- recursive node type -- */
2349
2350                 case XC( OC_VAR ):
2351                         L.v = op->l.v;
2352                         if (L.v == intvar[NF])
2353                                 split_f0();
2354                         goto v_cont;
2355
2356                 case XC( OC_FNARG ):
2357                         L.v = &fnargs[op->l.i];
2358  v_cont:
2359                         res = op->r.n ? findvar(iamarray(L.v), R.s) : L.v;
2360                         break;
2361
2362                 case XC( OC_IN ):
2363                         setvar_i(res, hash_search(iamarray(R.v), L.s) ? 1 : 0);
2364                         break;
2365
2366                 case XC( OC_REGEXP ):
2367                         op1 = op;
2368                         L.s = getvar_s(intvar[F0]);
2369                         goto re_cont;
2370
2371                 case XC( OC_MATCH ):
2372                         op1 = op->r.n;
2373  re_cont:
2374                         X.re = as_regex(op1, &sreg);
2375                         R.i = regexec(X.re, L.s, 0, NULL, 0);
2376                         if (X.re == &sreg) regfree(X.re);
2377                         setvar_i(res, (R.i == 0 ? 1 : 0) ^ (opn == '!' ? 1 : 0));
2378                         break;
2379
2380                 case XC( OC_MOVE ):
2381                         /* if source is a temporary string, jusk relink it to dest */
2382                         if (R.v == v1+1 && R.v->string) {
2383                                 res = setvar_p(L.v, R.v->string);
2384                                 R.v->string = NULL;
2385                         } else {
2386                                 res = copyvar(L.v, R.v);
2387                         }
2388                         break;
2389
2390                 case XC( OC_TERNARY ):
2391                         if ((op->r.n->info & OPCLSMASK) != OC_COLON)
2392                                 syntax_error(EMSG_POSSIBLE_ERROR);
2393                         res = evaluate(istrue(L.v) ? op->r.n->l.n : op->r.n->r.n, res);
2394                         break;
2395
2396                 case XC( OC_FUNC ):
2397                         if (!op->r.f->body.first)
2398                                 syntax_error(EMSG_UNDEF_FUNC);
2399
2400                         X.v = R.v = nvalloc(op->r.f->nargs+1);
2401                         while (op1) {
2402                                 L.v = evaluate(nextarg(&op1), v1);
2403                                 copyvar(R.v, L.v);
2404                                 R.v->type |= VF_CHILD;
2405                                 R.v->x.parent = L.v;
2406                                 if (++R.v - X.v >= op->r.f->nargs)
2407                                         break;
2408                         }
2409
2410                         R.v = fnargs;
2411                         fnargs = X.v;
2412
2413                         L.s = g_progname;
2414                         res = evaluate(op->r.f->body.first, res);
2415                         g_progname = L.s;
2416
2417                         nvfree(fnargs);
2418                         fnargs = R.v;
2419                         break;
2420
2421                 case XC( OC_GETLINE ):
2422                 case XC( OC_PGETLINE ):
2423                         if (op1) {
2424                                 X.rsm = newfile(L.s);
2425                                 if (!X.rsm->F) {
2426                                         if ((opinfo & OPCLSMASK) == OC_PGETLINE) {
2427                                                 X.rsm->F = popen(L.s, "r");
2428                                                 X.rsm->is_pipe = TRUE;
2429                                         } else {
2430                                                 X.rsm->F = fopen_for_read(L.s);         /* not xfopen! */
2431                                         }
2432                                 }
2433                         } else {
2434                                 if (!iF) iF = next_input_file();
2435                                 X.rsm = iF;
2436                         }
2437
2438                         if (!X.rsm->F) {
2439                                 setvar_i(intvar[ERRNO], errno);
2440                                 setvar_i(res, -1);
2441                                 break;
2442                         }
2443
2444                         if (!op->r.n)
2445                                 R.v = intvar[F0];
2446
2447                         L.i = awk_getline(X.rsm, R.v);
2448                         if (L.i > 0) {
2449                                 if (!op1) {
2450                                         incvar(intvar[FNR]);
2451                                         incvar(intvar[NR]);
2452                                 }
2453                         }
2454                         setvar_i(res, L.i);
2455                         break;
2456
2457                 /* simple builtins */
2458                 case XC( OC_FBLTIN ):
2459                         switch (opn) {
2460
2461                         case F_in:
2462                                 R.d = (int)L.d;
2463                                 break;
2464
2465                         case F_rn:
2466                                 R.d = (double)rand() / (double)RAND_MAX;
2467                                 break;
2468 #if ENABLE_FEATURE_AWK_MATH
2469                         case F_co:
2470                                 R.d = cos(L.d);
2471                                 break;
2472
2473                         case F_ex:
2474                                 R.d = exp(L.d);
2475                                 break;
2476
2477                         case F_lg:
2478                                 R.d = log(L.d);
2479                                 break;
2480
2481                         case F_si:
2482                                 R.d = sin(L.d);
2483                                 break;
2484
2485                         case F_sq:
2486                                 R.d = sqrt(L.d);
2487                                 break;
2488 #else
2489                         case F_co:
2490                         case F_ex:
2491                         case F_lg:
2492                         case F_si:
2493                         case F_sq:
2494                                 syntax_error(EMSG_NO_MATH);
2495                                 break;
2496 #endif
2497                         case F_sr:
2498                                 R.d = (double)seed;
2499                                 seed = op1 ? (unsigned)L.d : (unsigned)time(NULL);
2500                                 srand(seed);
2501                                 break;
2502
2503                         case F_ti:
2504                                 R.d = time(NULL);
2505                                 break;
2506
2507                         case F_le:
2508                                 if (!op1)
2509                                         L.s = getvar_s(intvar[F0]);
2510                                 R.d = strlen(L.s);
2511                                 break;
2512
2513                         case F_sy:
2514                                 fflush(NULL);
2515                                 R.d = (ENABLE_FEATURE_ALLOW_EXEC && L.s && *L.s)
2516                                                 ? (system(L.s) >> 8) : 0;
2517                                 break;
2518
2519                         case F_ff:
2520                                 if (!op1)
2521                                         fflush(stdout);
2522                                 else {
2523                                         if (L.s && *L.s) {
2524                                                 X.rsm = newfile(L.s);
2525                                                 fflush(X.rsm->F);
2526                                         } else {
2527                                                 fflush(NULL);
2528                                         }
2529                                 }
2530                                 break;
2531
2532                         case F_cl:
2533                                 X.rsm = (rstream *)hash_search(fdhash, L.s);
2534                                 if (X.rsm) {
2535                                         R.i = X.rsm->is_pipe ? pclose(X.rsm->F) : fclose(X.rsm->F);
2536                                         free(X.rsm->buffer);
2537                                         hash_remove(fdhash, L.s);
2538                                 }
2539                                 if (R.i != 0)
2540                                         setvar_i(intvar[ERRNO], errno);
2541                                 R.d = (double)R.i;
2542                                 break;
2543                         }
2544                         setvar_i(res, R.d);
2545                         break;
2546
2547                 case XC( OC_BUILTIN ):
2548                         res = exec_builtin(op, res);
2549                         break;
2550
2551                 case XC( OC_SPRINTF ):
2552                         setvar_p(res, awk_printf(op1));
2553                         break;
2554
2555                 case XC( OC_UNARY ):
2556                         X.v = R.v;
2557                         L.d = R.d = getvar_i(R.v);
2558                         switch (opn) {
2559                         case 'P':
2560                                 L.d = ++R.d;
2561                                 goto r_op_change;
2562                         case 'p':
2563                                 R.d++;
2564                                 goto r_op_change;
2565                         case 'M':
2566                                 L.d = --R.d;
2567                                 goto r_op_change;
2568                         case 'm':
2569                                 R.d--;
2570                                 goto r_op_change;
2571                         case '!':
2572                                 L.d = istrue(X.v) ? 0 : 1;
2573                                 break;
2574                         case '-':
2575                                 L.d = -R.d;
2576                                 break;
2577  r_op_change:
2578                                 setvar_i(X.v, R.d);
2579                         }
2580                         setvar_i(res, L.d);
2581                         break;
2582
2583                 case XC( OC_FIELD ):
2584                         R.i = (int)getvar_i(R.v);
2585                         if (R.i == 0) {
2586                                 res = intvar[F0];
2587                         } else {
2588                                 split_f0();
2589                                 if (R.i > nfields)
2590                                         fsrealloc(R.i);
2591                                 res = &Fields[R.i - 1];
2592                         }
2593                         break;
2594
2595                 /* concatenation (" ") and index joining (",") */
2596                 case XC( OC_CONCAT ):
2597                 case XC( OC_COMMA ):
2598                         opn = strlen(L.s) + strlen(R.s) + 2;
2599                         X.s = xmalloc(opn);
2600                         strcpy(X.s, L.s);
2601                         if ((opinfo & OPCLSMASK) == OC_COMMA) {
2602                                 L.s = getvar_s(intvar[SUBSEP]);
2603                                 X.s = xrealloc(X.s, opn + strlen(L.s));
2604                                 strcat(X.s, L.s);
2605                         }
2606                         strcat(X.s, R.s);
2607                         setvar_p(res, X.s);
2608                         break;
2609
2610                 case XC( OC_LAND ):
2611                         setvar_i(res, istrue(L.v) ? ptest(op->r.n) : 0);
2612                         break;
2613
2614                 case XC( OC_LOR ):
2615                         setvar_i(res, istrue(L.v) ? 1 : ptest(op->r.n));
2616                         break;
2617
2618                 case XC( OC_BINARY ):
2619                 case XC( OC_REPLACE ):
2620                         R.d = getvar_i(R.v);
2621                         switch (opn) {
2622                         case '+':
2623                                 L.d += R.d;
2624                                 break;
2625                         case '-':
2626                                 L.d -= R.d;
2627                                 break;
2628                         case '*':
2629                                 L.d *= R.d;
2630                                 break;
2631                         case '/':
2632                                 if (R.d == 0) syntax_error(EMSG_DIV_BY_ZERO);
2633                                 L.d /= R.d;
2634                                 break;
2635                         case '&':
2636 #if ENABLE_FEATURE_AWK_MATH
2637                                 L.d = pow(L.d, R.d);
2638 #else
2639                                 syntax_error(EMSG_NO_MATH);
2640 #endif
2641                                 break;
2642                         case '%':
2643                                 if (R.d == 0) syntax_error(EMSG_DIV_BY_ZERO);
2644                                 L.d -= (int)(L.d / R.d) * R.d;
2645                                 break;
2646                         }
2647                         res = setvar_i(((opinfo & OPCLSMASK) == OC_BINARY) ? res : X.v, L.d);
2648                         break;
2649
2650                 case XC( OC_COMPARE ):
2651                         if (is_numeric(L.v) && is_numeric(R.v)) {
2652                                 L.d = getvar_i(L.v) - getvar_i(R.v);
2653                         } else {
2654                                 L.s = getvar_s(L.v);
2655                                 R.s = getvar_s(R.v);
2656                                 L.d = icase ? strcasecmp(L.s, R.s) : strcmp(L.s, R.s);
2657                         }
2658                         switch (opn & 0xfe) {
2659                         case 0:
2660                                 R.i = (L.d > 0);
2661                                 break;
2662                         case 2:
2663                                 R.i = (L.d >= 0);
2664                                 break;
2665                         case 4:
2666                                 R.i = (L.d == 0);
2667                                 break;
2668                         }
2669                         setvar_i(res, (opn & 0x1 ? R.i : !R.i) ? 1 : 0);
2670                         break;
2671
2672                 default:
2673                         syntax_error(EMSG_POSSIBLE_ERROR);
2674                 }
2675                 if ((opinfo & OPCLSMASK) <= SHIFT_TIL_THIS)
2676                         op = op->a.n;
2677                 if ((opinfo & OPCLSMASK) >= RECUR_FROM_THIS)
2678                         break;
2679                 if (nextrec)
2680                         break;
2681         }
2682         nvfree(v1);
2683         return res;
2684 #undef fnargs
2685 #undef seed
2686 #undef sreg
2687 }
2688
2689
2690 /* -------- main & co. -------- */
2691
2692 static int awk_exit(int r)
2693 {
2694         var tv;
2695         unsigned i;
2696         hash_item *hi;
2697
2698         zero_out_var(&tv);
2699
2700         if (!exiting) {
2701                 exiting = TRUE;
2702                 nextrec = FALSE;
2703                 evaluate(endseq.first, &tv);
2704         }
2705
2706         /* waiting for children */
2707         for (i = 0; i < fdhash->csize; i++) {
2708                 hi = fdhash->items[i];
2709                 while (hi) {
2710                         if (hi->data.rs.F && hi->data.rs.is_pipe)
2711                                 pclose(hi->data.rs.F);
2712                         hi = hi->next;
2713                 }
2714         }
2715
2716         exit(r);
2717 }
2718
2719 /* if expr looks like "var=value", perform assignment and return 1,
2720  * otherwise return 0 */
2721 static int is_assignment(const char *expr)
2722 {
2723         char *exprc, *s, *s0, *s1;
2724
2725         exprc = xstrdup(expr);
2726         if (!isalnum_(*exprc) || (s = strchr(exprc, '=')) == NULL) {
2727                 free(exprc);
2728                 return FALSE;
2729         }
2730
2731         *(s++) = '\0';
2732         s0 = s1 = s;
2733         while (*s)
2734                 *(s1++) = nextchar(&s);
2735
2736         *s1 = '\0';
2737         setvar_u(newvar(exprc), s0);
2738         free(exprc);
2739         return TRUE;
2740 }
2741
2742 /* switch to next input file */
2743 static rstream *next_input_file(void)
2744 {
2745 #define rsm          (G.next_input_file__rsm)
2746 #define files_happen (G.next_input_file__files_happen)
2747
2748         FILE *F = NULL;
2749         const char *fname, *ind;
2750
2751         if (rsm.F) fclose(rsm.F);
2752         rsm.F = NULL;
2753         rsm.pos = rsm.adv = 0;
2754
2755         do {
2756                 if (getvar_i(intvar[ARGIND])+1 >= getvar_i(intvar[ARGC])) {
2757                         if (files_happen)
2758                                 return NULL;
2759                         fname = "-";
2760                         F = stdin;
2761                 } else {
2762                         ind = getvar_s(incvar(intvar[ARGIND]));
2763                         fname = getvar_s(findvar(iamarray(intvar[ARGV]), ind));
2764                         if (fname && *fname && !is_assignment(fname))
2765                                 F = xfopen_stdin(fname);
2766                 }
2767         } while (!F);
2768
2769         files_happen = TRUE;
2770         setvar_s(intvar[FILENAME], fname);
2771         rsm.F = F;
2772         return &rsm;
2773 #undef rsm
2774 #undef files_happen
2775 }
2776
2777 int awk_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
2778 int awk_main(int argc, char **argv)
2779 {
2780         unsigned opt;
2781         char *opt_F, *opt_W;
2782         llist_t *list_v = NULL;
2783         llist_t *list_f = NULL;
2784         int i, j;
2785         var *v;
2786         var tv;
2787         char **envp;
2788         char *vnames = (char *)vNames; /* cheat */
2789         char *vvalues = (char *)vValues;
2790
2791         INIT_G();
2792
2793         /* Undo busybox.c, or else strtod may eat ','! This breaks parsing:
2794          * $1,$2 == '$1,' '$2', NOT '$1' ',' '$2' */
2795         if (ENABLE_LOCALE_SUPPORT)
2796                 setlocale(LC_NUMERIC, "C");
2797
2798         zero_out_var(&tv);
2799
2800         /* allocate global buffer */
2801         g_buf = xmalloc(MAXVARFMT + 1);
2802
2803         vhash = hash_init();
2804         ahash = hash_init();
2805         fdhash = hash_init();
2806         fnhash = hash_init();
2807
2808         /* initialize variables */
2809         for (i = 0; *vnames; i++) {
2810                 intvar[i] = v = newvar(nextword(&vnames));
2811                 if (*vvalues != '\377')
2812                         setvar_s(v, nextword(&vvalues));
2813                 else
2814                         setvar_i(v, 0);
2815
2816                 if (*vnames == '*') {
2817                         v->type |= VF_SPECIAL;
2818                         vnames++;
2819                 }
2820         }
2821
2822         handle_special(intvar[FS]);
2823         handle_special(intvar[RS]);
2824
2825         newfile("/dev/stdin")->F = stdin;
2826         newfile("/dev/stdout")->F = stdout;
2827         newfile("/dev/stderr")->F = stderr;
2828
2829         /* Huh, people report that sometimes environ is NULL. Oh well. */
2830         if (environ) for (envp = environ; *envp; envp++) {
2831                 /* environ is writable, thus we don't strdup it needlessly */
2832                 char *s = *envp;
2833                 char *s1 = strchr(s, '=');
2834                 if (s1) {
2835                         *s1 = '\0';
2836                         /* Both findvar and setvar_u take const char*
2837                          * as 2nd arg -> environment is not trashed */
2838                         setvar_u(findvar(iamarray(intvar[ENVIRON]), s), s1 + 1);
2839                         *s1 = '=';
2840                 }
2841         }
2842         opt_complementary = "v::f::"; /* -v and -f can occur multiple times */
2843         opt = getopt32(argv, "F:v:f:W:", &opt_F, &list_v, &list_f, &opt_W);
2844         argv += optind;
2845         argc -= optind;
2846         if (opt & 0x1)
2847                 setvar_s(intvar[FS], opt_F); // -F
2848         while (list_v) { /* -v */
2849                 if (!is_assignment(llist_pop(&list_v)))
2850                         bb_show_usage();
2851         }
2852         if (list_f) { /* -f */
2853                 do {
2854                         char *s = NULL;
2855                         FILE *from_file;
2856
2857                         g_progname = llist_pop(&list_f);
2858                         from_file = xfopen_stdin(g_progname);
2859                         /* one byte is reserved for some trick in next_token */
2860                         for (i = j = 1; j > 0; i += j) {
2861                                 s = xrealloc(s, i + 4096);
2862                                 j = fread(s + i, 1, 4094, from_file);
2863                         }
2864                         s[i] = '\0';
2865                         fclose(from_file);
2866                         parse_program(s + 1);
2867                         free(s);
2868                 } while (list_f);
2869         } else { // no -f: take program from 1st parameter
2870                 if (!argc)
2871                         bb_show_usage();
2872                 g_progname = "cmd. line";
2873                 parse_program(*argv++);
2874                 argc--;
2875         }
2876         if (opt & 0x8) // -W
2877                 bb_error_msg("warning: unrecognized option '-W %s' ignored", opt_W);
2878
2879         /* fill in ARGV array */
2880         setvar_i(intvar[ARGC], argc + 1);
2881         setari_u(intvar[ARGV], 0, "awk");
2882         i = 0;
2883         while (*argv)
2884                 setari_u(intvar[ARGV], ++i, *argv++);
2885
2886         evaluate(beginseq.first, &tv);
2887         if (!mainseq.first && !endseq.first)
2888                 awk_exit(EXIT_SUCCESS);
2889
2890         /* input file could already be opened in BEGIN block */
2891         if (!iF) iF = next_input_file();
2892
2893         /* passing through input files */
2894         while (iF) {
2895                 nextfile = FALSE;
2896                 setvar_i(intvar[FNR], 0);
2897
2898                 while ((i = awk_getline(iF, intvar[F0])) > 0) {
2899                         nextrec = FALSE;
2900                         incvar(intvar[NR]);
2901                         incvar(intvar[FNR]);
2902                         evaluate(mainseq.first, &tv);
2903
2904                         if (nextfile)
2905                                 break;
2906                 }
2907
2908                 if (i < 0)
2909                         syntax_error(strerror(errno));
2910
2911                 iF = next_input_file();
2912         }
2913
2914         awk_exit(EXIT_SUCCESS);
2915         /*return 0;*/
2916 }