/*      $NetBSD: test.c,v 1.21 1999/04/05 09:48:38 kleink Exp $ */

/*-
 * test(1); version 7-like  --  author Erik Baalbergen
 * modified by Eric Gisin to be used as built-in.
 * modified by Arnold Robbins to add SVR3 compatibility
 * (-x -c -b -p -u -g -k) plus Korn's -L -nt -ot -ef and new -S (socket).
 * modified by J.T. Conklin for NetBSD.
 *
 * This program is in the Public Domain.
 */
/*
 * Important: This file is used both as a standalone program /bin/test and
 * as a builtin for /bin/sh (#define SHELL).
 */

#include <sys/types.h>
#include <sys/stat.h>

#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <inttypes.h>
#include <stdarg.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#ifdef SHELL
#define main testcmd
#include "bltin/bltin.h"
#else
#include <locale.h>

static void error(const char *, ...) __dead2 __printf0like(1, 2);

static void
error(const char *msg, ...)
{
        va_list ap;
        va_start(ap, msg);
        verrx(2, msg, ap);
        /*NOTREACHED*/
        va_end(ap);
}
#endif

/* test(1) accepts the following grammar:
        oexpr   ::= aexpr | aexpr "-o" oexpr ;
        aexpr   ::= nexpr | nexpr "-a" aexpr ;
        nexpr   ::= primary | "!" primary
        primary ::= unary-operator operand
                | operand binary-operator operand
                | operand
                | "(" oexpr ")"
                ;
        unary-operator ::= "-r"|"-w"|"-x"|"-f"|"-d"|"-c"|"-b"|"-p"|
                "-u"|"-g"|"-k"|"-s"|"-t"|"-z"|"-n"|"-o"|"-O"|"-G"|"-L"|"-S";

        binary-operator ::= "="|"!="|"-eq"|"-ne"|"-ge"|"-gt"|"-le"|"-lt"|
                        "-nt"|"-ot"|"-ef";
        operand ::= <any legal UNIX file name>
*/

enum token_types {
        UNOP = 0x100,
        BINOP = 0x200,
        BUNOP = 0x300,
        BBINOP = 0x400,
        PAREN = 0x500
};

enum token {
        EOI,
        OPERAND,
        FILRD = UNOP + 1,
        FILWR,
        FILEX,
        FILEXIST,
        FILREG,
        FILDIR,
        FILCDEV,
        FILBDEV,
        FILFIFO,
        FILSOCK,
        FILSYM,
        FILGZ,
        FILTT,
        FILSUID,
        FILSGID,
        FILSTCK,
        STREZ,
        STRNZ,
        FILUID,
        FILGID,
        FILNT = BINOP + 1,
        FILOT,
        FILEQ,
        STREQ,
        STRNE,
        STRLT,
        STRGT,
        INTEQ,
        INTNE,
        INTGE,
        INTGT,
        INTLE,
        INTLT,
        UNOT = BUNOP + 1,
        BAND = BBINOP + 1,
        BOR,
        LPAREN = PAREN + 1,
        RPAREN
};

#define TOKEN_TYPE(token) ((token) & 0xff00)

static const struct t_op {
        char op_text[2] __nonstring;
        short op_num;
} ops1[] = {
        {"=",   STREQ},
        {"<",   STRLT},
        {">",   STRGT},
        {"!",   UNOT},
        {"(",   LPAREN},
        {")",   RPAREN},
}, opsm1[] = {
        {"r",   FILRD},
        {"w",   FILWR},
        {"x",   FILEX},
        {"e",   FILEXIST},
        {"f",   FILREG},
        {"d",   FILDIR},
        {"c",   FILCDEV},
        {"b",   FILBDEV},
        {"p",   FILFIFO},
        {"u",   FILSUID},
        {"g",   FILSGID},
        {"k",   FILSTCK},
        {"s",   FILGZ},
        {"t",   FILTT},
        {"z",   STREZ},
        {"n",   STRNZ},
        {"h",   FILSYM},                /* for backwards compat */
        {"O",   FILUID},
        {"G",   FILGID},
        {"L",   FILSYM},
        {"S",   FILSOCK},
        {"a",   BAND},
        {"o",   BOR},
}, ops2[] = {
        {"==",  STREQ},
        {"!=",  STRNE},
}, opsm2[] = {
        {"eq",  INTEQ},
        {"ne",  INTNE},
        {"ge",  INTGE},
        {"gt",  INTGT},
        {"le",  INTLE},
        {"lt",  INTLT},
        {"nt",  FILNT},
        {"ot",  FILOT},
        {"ef",  FILEQ},
};

static int nargc;
static char **t_wp;
static int parenlevel;

static int      aexpr(enum token);
static int      binop(enum token);
static int      equalf(const char *, const char *);
static int      filstat(char *, enum token);
static int      getn(const char *);
static intmax_t getq(const char *);
static int      intcmp(const char *, const char *);
static int      isunopoperand(void);
static int      islparenoperand(void);
static int      isrparenoperand(void);
static int      newerf(const char *, const char *);
static int      nexpr(enum token);
static int      oexpr(enum token);
static int      olderf(const char *, const char *);
static int      primary(enum token);
static void     syntax(const char *, const char *);
static enum     token t_lex(char *);

int
main(int argc, char **argv)
{
        int     res;
        char    *p;

        if ((p = strrchr(argv[0], '/')) == NULL)
                p = argv[0];
        else
                p++;
        if (strcmp(p, "[") == 0) {
                if (strcmp(argv[--argc], "]") != 0)
                        error("missing ']'");
                argv[argc] = NULL;
        }

        /* no expression => false */
        if (--argc <= 0)
                return 1;

#ifndef SHELL
        (void)setlocale(LC_CTYPE, "");
#endif
        nargc = argc;
        t_wp = &argv[1];
        parenlevel = 0;
        if (nargc == 4 && strcmp(*t_wp, "!") == 0) {
                /* Things like ! "" -o x do not fit in the normal grammar. */
                --nargc;
                ++t_wp;
                res = oexpr(t_lex(*t_wp));
        } else
                res = !oexpr(t_lex(*t_wp));

        if (--nargc > 0)
                syntax(*t_wp, "unexpected operator");

        return res;
}

static void
syntax(const char *op, const char *msg)
{

        if (op && *op)
                error("%s: %s", op, msg);
        else
                error("%s", msg);
}

static int
oexpr(enum token n)
{
        int res;

        res = aexpr(n);
        if (t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL) == BOR)
                return oexpr(t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL)) ||
                    res;
        t_wp--;
        nargc++;
        return res;
}

static int
aexpr(enum token n)
{
        int res;

        res = nexpr(n);
        if (t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL) == BAND)
                return aexpr(t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL)) &&
                    res;
        t_wp--;
        nargc++;
        return res;
}

static int
nexpr(enum token n)
{
        if (n == UNOT)
                return !nexpr(t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL));
        return primary(n);
}

static int
primary(enum token n)
{
        enum token nn;
        int res;

        if (n == EOI)
                return 0;               /* missing expression */
        if (n == LPAREN) {
                parenlevel++;
                if ((nn = t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL)) ==
                    RPAREN) {
                        parenlevel--;
                        return 0;       /* missing expression */
                }
                res = oexpr(nn);
                if (t_lex(nargc > 0 ? (--nargc, *++t_wp) : NULL) != RPAREN)
                        syntax(NULL, "closing paren expected");
                parenlevel--;
                return res;
        }
        if (TOKEN_TYPE(n) == UNOP) {
                /* unary expression */
                if (--nargc == 0)
                        syntax(NULL, "argument expected"); /* impossible */
                switch (n) {
                case STREZ:
                        return strlen(*++t_wp) == 0;
                case STRNZ:
                        return strlen(*++t_wp) != 0;
                case FILTT:
                        return isatty(getn(*++t_wp));
                default:
                        return filstat(*++t_wp, n);
                }
        }

        nn = t_lex(nargc > 0 ? t_wp[1] : NULL);
        if (TOKEN_TYPE(nn) == BINOP)
                return binop(nn);

        return strlen(*t_wp) > 0;
}

static int
binop(enum token n)
{
        const char *opnd1, *op, *opnd2;

        opnd1 = *t_wp;
        op = nargc > 0 ? (--nargc, *++t_wp) : NULL;

        if ((opnd2 = nargc > 0 ? (--nargc, *++t_wp) : NULL) == NULL)
                syntax(op, "argument expected");

        switch (n) {
        case STREQ:
                return strcmp(opnd1, opnd2) == 0;
        case STRNE:
                return strcmp(opnd1, opnd2) != 0;
        case STRLT:
                return strcmp(opnd1, opnd2) < 0;
        case STRGT:
                return strcmp(opnd1, opnd2) > 0;
        case INTEQ:
                return intcmp(opnd1, opnd2) == 0;
        case INTNE:
                return intcmp(opnd1, opnd2) != 0;
        case INTGE:
                return intcmp(opnd1, opnd2) >= 0;
        case INTGT:
                return intcmp(opnd1, opnd2) > 0;
        case INTLE:
                return intcmp(opnd1, opnd2) <= 0;
        case INTLT:
                return intcmp(opnd1, opnd2) < 0;
        case FILNT:
                return newerf (opnd1, opnd2);
        case FILOT:
                return olderf (opnd1, opnd2);
        case FILEQ:
                return equalf (opnd1, opnd2);
        default:
                abort();
                /* NOTREACHED */
        }
}

static int
filstat(char *nm, enum token mode)
{
        struct stat s;

        if (mode == FILSYM ? lstat(nm, &s) : stat(nm, &s))
                return 0;

        switch (mode) {
        case FILRD:
                return (eaccess(nm, R_OK) == 0);
        case FILWR:
                return (eaccess(nm, W_OK) == 0);
        case FILEX:
                /* XXX work around eaccess(2) false positives for superuser */
                if (eaccess(nm, X_OK) != 0)
                        return 0;
                if (S_ISDIR(s.st_mode) || geteuid() != 0)
                        return 1;
                return (s.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH)) != 0;
        case FILEXIST:
                return (eaccess(nm, F_OK) == 0);
        case FILREG:
                return S_ISREG(s.st_mode);
        case FILDIR:
                return S_ISDIR(s.st_mode);
        case FILCDEV:
                return S_ISCHR(s.st_mode);
        case FILBDEV:
                return S_ISBLK(s.st_mode);
        case FILFIFO:
                return S_ISFIFO(s.st_mode);
        case FILSOCK:
                return S_ISSOCK(s.st_mode);
        case FILSYM:
                return S_ISLNK(s.st_mode);
        case FILSUID:
                return (s.st_mode & S_ISUID) != 0;
        case FILSGID:
                return (s.st_mode & S_ISGID) != 0;
        case FILSTCK:
                return (s.st_mode & S_ISVTX) != 0;
        case FILGZ:
                return s.st_size > (off_t)0;
        case FILUID:
                return s.st_uid == geteuid();
        case FILGID:
                return s.st_gid == getegid();
        default:
                return 1;
        }
}

static int
find_op_1char(const struct t_op *op, const struct t_op *end, const char *s)
{
        char c;

        c = s[0];
        while (op != end) {
                if (c == *op->op_text)
                        return op->op_num;
                op++;
        }
        return OPERAND;
}

static int
find_op_2char(const struct t_op *op, const struct t_op *end, const char *s)
{
        while (op != end) {
                if (s[0] == op->op_text[0] && s[1] == op->op_text[1])
                        return op->op_num;
                op++;
        }
        return OPERAND;
}

static int
find_op(const char *s)
{
        if (s[0] == '\0')
                return OPERAND;
        else if (s[1] == '\0')
                return find_op_1char(ops1, (&ops1)[1], s);
        else if (s[2] == '\0')
                return s[0] == '-' ? find_op_1char(opsm1, (&opsm1)[1], s + 1) :
                    find_op_2char(ops2, (&ops2)[1], s);
        else if (s[3] == '\0')
                return s[0] == '-' ? find_op_2char(opsm2, (&opsm2)[1], s + 1) :
                    OPERAND;
        else
                return OPERAND;
}

static enum token
t_lex(char *s)
{
        int num;

        if (s == NULL) {
                return EOI;
        }
        num = find_op(s);
        if (((TOKEN_TYPE(num) == UNOP || TOKEN_TYPE(num) == BUNOP)
                                && isunopoperand()) ||
            (num == LPAREN && islparenoperand()) ||
            (num == RPAREN && isrparenoperand()))
                return OPERAND;
        return num;
}

static int
isunopoperand(void)
{
        char *s;
        char *t;
        int num;

        if (nargc == 1)
                return 1;
        s = *(t_wp + 1);
        if (nargc == 2)
                return parenlevel == 1 && strcmp(s, ")") == 0;
        t = *(t_wp + 2);
        num = find_op(s);
        return TOKEN_TYPE(num) == BINOP &&
            (parenlevel == 0 || t[0] != ')' || t[1] != '\0');
}

static int
islparenoperand(void)
{
        char *s;
        int num;

        if (nargc == 1)
                return 1;
        s = *(t_wp + 1);
        if (nargc == 2)
                return parenlevel == 1 && strcmp(s, ")") == 0;
        if (nargc != 3)
                return 0;
        num = find_op(s);
        return TOKEN_TYPE(num) == BINOP;
}

static int
isrparenoperand(void)
{
        char *s;

        if (nargc == 1)
                return 0;
        s = *(t_wp + 1);
        if (nargc == 2)
                return parenlevel == 1 && strcmp(s, ")") == 0;
        return 0;
}

/* atoi with error detection */
static int
getn(const char *s)
{
        char *p;
        long r;

        errno = 0;
        r = strtol(s, &p, 10);

        if (s == p)
                error("%s: bad number", s);

        if (errno != 0)
                error((errno == EINVAL) ? "%s: bad number" :
                                          "%s: out of range", s);

        while (isspace((unsigned char)*p))
                p++;

        if (*p)
                error("%s: bad number", s);

        return (int) r;
}

/* atoi with error detection and 64 bit range */
static intmax_t
getq(const char *s)
{
        char *p;
        intmax_t r;

        errno = 0;
        r = strtoimax(s, &p, 10);

        if (s == p)
                error("%s: bad number", s);

        if (errno != 0)
                error((errno == EINVAL) ? "%s: bad number" :
                                          "%s: out of range", s);

        while (isspace((unsigned char)*p))
                p++;

        if (*p)
                error("%s: bad number", s);

        return r;
}

static int
intcmp (const char *s1, const char *s2)
{
        intmax_t q1, q2;


        q1 = getq(s1);
        q2 = getq(s2);

        if (q1 > q2)
                return 1;

        if (q1 < q2)
                return -1;

        return 0;
}

static int
newerf (const char *f1, const char *f2)
{
        struct stat b1, b2;

        if (stat(f1, &b1) != 0 || stat(f2, &b2) != 0)
                return 0;

        if (b1.st_mtim.tv_sec > b2.st_mtim.tv_sec)
                return 1;
        if (b1.st_mtim.tv_sec < b2.st_mtim.tv_sec)
                return 0;

       return (b1.st_mtim.tv_nsec > b2.st_mtim.tv_nsec);
}

static int
olderf (const char *f1, const char *f2)
{
        return (newerf(f2, f1));
}

static int
equalf (const char *f1, const char *f2)
{
        struct stat b1, b2;

        return (stat (f1, &b1) == 0 &&
                stat (f2, &b2) == 0 &&
                b1.st_dev == b2.st_dev &&
                b1.st_ino == b2.st_ino);
}