ash.c

shell-HHARM9200.rar 华恒 AT91rm9200 中Busybox shell的源代码

};


struct nhere {
      int type;
      union node *next;
      int fd;
      union node *doc;
};


struct nnot {
      int type;
      union node *com;
};


union node {
      int type;
      struct ncmd ncmd;
      struct npipe npipe;
      struct nredir nredir;
      struct nbinary nbinary;
      struct nif nif;
      struct nfor nfor;
      struct ncase ncase;
      struct nclist nclist;
      struct narg narg;
      struct nfile nfile;
      struct ndup ndup;
      struct nhere nhere;
      struct nnot nnot;
};


struct nodelist {
	struct nodelist *next;
	union node *n;
};


struct funcnode {
	int count;
	union node n;
};


static void freefunc(struct funcnode *);
/*      $NetBSD: parser.h,v 1.15 2002/11/24 22:35:42 christos Exp $     */

/* control characters in argument strings */
#define CTL_FIRST '\201'        /* first 'special' character */
#define CTLESC '\201'           /* escape next character */
#define CTLVAR '\202'           /* variable defn */
#define CTLENDVAR '\203'
#define CTLBACKQ '\204'
#define CTLQUOTE 01             /* ored with CTLBACKQ code if in quotes */
/*      CTLBACKQ | CTLQUOTE == '\205' */
#define CTLARI  '\206'          /* arithmetic expression */
#define CTLENDARI '\207'
#define CTLQUOTEMARK '\210'
#define CTL_LAST '\210'         /* last 'special' character */

/* variable substitution byte (follows CTLVAR) */
#define VSTYPE  0x0f            /* type of variable substitution */
#define VSNUL   0x10            /* colon--treat the empty string as unset */
#define VSQUOTE 0x80            /* inside double quotes--suppress splitting */

/* values of VSTYPE field */
#define VSNORMAL        0x1             /* normal variable:  $var or ${var} */
#define VSMINUS         0x2             /* ${var-text} */
#define VSPLUS          0x3             /* ${var+text} */
#define VSQUESTION      0x4             /* ${var?message} */
#define VSASSIGN        0x5             /* ${var=text} */
#define VSTRIMRIGHT     0x6             /* ${var%pattern} */
#define VSTRIMRIGHTMAX  0x7             /* ${var%%pattern} */
#define VSTRIMLEFT      0x8             /* ${var#pattern} */
#define VSTRIMLEFTMAX   0x9             /* ${var##pattern} */
#define VSLENGTH        0xa             /* ${#var} */

/* values of checkkwd variable */
#define CHKALIAS        0x1
#define CHKKWD          0x2
#define CHKNL           0x4

#define IBUFSIZ (BUFSIZ + 1)

/*
 * NEOF is returned by parsecmd when it encounters an end of file.  It
 * must be distinct from NULL, so we use the address of a variable that
 * happens to be handy.
 */
static int plinno = 1;                  /* input line number */

/* number of characters left in input buffer */
static int parsenleft;                  /* copy of parsefile->nleft */
static int parselleft;                  /* copy of parsefile->lleft */

/* next character in input buffer */
static char *parsenextc;                /* copy of parsefile->nextc */

struct strpush {
	struct strpush *prev;   /* preceding string on stack */
	char *prevstring;
	int prevnleft;
#ifdef CONFIG_ASH_ALIAS
	struct alias *ap;       /* if push was associated with an alias */
#endif
	char *string;           /* remember the string since it may change */
};

struct parsefile {
	struct parsefile *prev; /* preceding file on stack */
	int linno;              /* current line */
	int fd;                 /* file descriptor (or -1 if string) */
	int nleft;              /* number of chars left in this line */
	int lleft;              /* number of chars left in this buffer */
	char *nextc;            /* next char in buffer */
	char *buf;              /* input buffer */
	struct strpush *strpush; /* for pushing strings at this level */
	struct strpush basestrpush; /* so pushing one is fast */
};

static struct parsefile basepf;         /* top level input file */
static char basebuf[IBUFSIZ];           /* buffer for top level input file */
static struct parsefile *parsefile = &basepf;  /* current input file */


static int tokpushback;                 /* last token pushed back */
#define NEOF ((union node *)&tokpushback)
static int parsebackquote;             /* nonzero if we are inside backquotes */
static int doprompt;                   /* if set, prompt the user */
static int needprompt;                 /* true if interactive and at start of line */
static int lasttoken;                  /* last token read */
static char *wordtext;                 /* text of last word returned by readtoken */
static int checkkwd;
static struct nodelist *backquotelist;
static union node *redirnode;
static struct heredoc *heredoc;
static int quoteflag;                  /* set if (part of) last token was quoted */
static int startlinno;                 /* line # where last token started */

static union node *parsecmd(int);
static void fixredir(union node *, const char *, int);
static const char *const *findkwd(const char *);
static char *endofname(const char *);

/*      $NetBSD: shell.h,v 1.16 2003/01/22 20:36:04 dsl Exp $   */

typedef void *pointer;

static char nullstr[1];                /* zero length string */
static const char spcstr[] = " ";
static const char snlfmt[] = "%s\n";
static const char dolatstr[] = { CTLVAR, VSNORMAL|VSQUOTE, '@', '=', '\0' };
static const char illnum[] = "Illegal number: %s";
static const char homestr[] = "HOME";

#ifdef DEBUG
#define TRACE(param)    trace param
#define TRACEV(param)   tracev param
#else
#define TRACE(param)
#define TRACEV(param)
#endif

#if !defined(__GNUC__) || (__GNUC__ == 2 && __GNUC_MINOR__ < 96)
#define __builtin_expect(x, expected_value) (x)
#endif

#define likely(x)       __builtin_expect((x),1)


#define TEOF 0
#define TNL 1
#define TREDIR 2
#define TWORD 3
#define TSEMI 4
#define TBACKGND 5
#define TAND 6
#define TOR 7
#define TPIPE 8
#define TLP 9
#define TRP 10
#define TENDCASE 11
#define TENDBQUOTE 12
#define TNOT 13
#define TCASE 14
#define TDO 15
#define TDONE 16
#define TELIF 17
#define TELSE 18
#define TESAC 19
#define TFI 20
#define TFOR 21
#define TIF 22
#define TIN 23
#define TTHEN 24
#define TUNTIL 25
#define TWHILE 26
#define TBEGIN 27
#define TEND 28

/* first char is indicating which tokens mark the end of a list */
static const char *const tokname_array[] = {
	"\1end of file",
	"\0newline",
	"\0redirection",
	"\0word",
	"\0;",
	"\0&",
	"\0&&",
	"\0||",
	"\0|",
	"\0(",
	"\1)",
	"\1;;",
	"\1`",
#define KWDOFFSET 13
	/* the following are keywords */
	"\0!",
	"\0case",
	"\1do",
	"\1done",
	"\1elif",
	"\1else",
	"\1esac",
	"\1fi",
	"\0for",
	"\0if",
	"\0in",
	"\1then",
	"\0until",
	"\0while",
	"\0{",
	"\1}",
};

static const char *tokname(int tok)
{
	static char buf[16];

	if (tok >= TSEMI)
		buf[0] = '"';
	sprintf(buf + (tok >= TSEMI), "%s%c",
			tokname_array[tok] + 1, (tok >= TSEMI ? '"' : 0));
	return buf;
}

/*      $NetBSD: machdep.h,v 1.10 2002/10/07 14:26:08 christos Exp $    */

/*
 * Most machines require the value returned from malloc to be aligned
 * in some way.  The following macro will get this right on many machines.
 */

#define SHELL_SIZE (sizeof(union {int i; char *cp; double d; }) - 1)
/*
 * It appears that grabstackstr() will barf with such alignments
 * because stalloc() will return a string allocated in a new stackblock.
 */
#define SHELL_ALIGN(nbytes) (((nbytes) + SHELL_SIZE) & ~SHELL_SIZE)

/*
 * This file was generated by the mksyntax program.
 */


/* Syntax classes */
#define CWORD 0                 /* character is nothing special */
#define CNL 1                   /* newline character */
#define CBACK 2                 /* a backslash character */
#define CSQUOTE 3               /* single quote */
#define CDQUOTE 4               /* double quote */
#define CENDQUOTE 5             /* a terminating quote */
#define CBQUOTE 6               /* backwards single quote */
#define CVAR 7                  /* a dollar sign */
#define CENDVAR 8               /* a '}' character */
#define CLP 9                   /* a left paren in arithmetic */
#define CRP 10                  /* a right paren in arithmetic */
#define CENDFILE 11             /* end of file */
#define CCTL 12                 /* like CWORD, except it must be escaped */
#define CSPCL 13                /* these terminate a word */
#define CIGN 14                 /* character should be ignored */

#ifdef CONFIG_ASH_ALIAS
#define SYNBASE 130
#define PEOF -130
#define PEOA -129
#define PEOA_OR_PEOF PEOA
#else
#define SYNBASE 129
#define PEOF -129
#define PEOA_OR_PEOF PEOF
#endif

#define is_digit(c)     ((unsigned)((c) - '0') <= 9)
#define is_name(c)      ((c) == '_' || isalpha((unsigned char)(c)))
#define is_in_name(c)   ((c) == '_' || isalnum((unsigned char)(c)))

/*
 * is_special(c) evaluates to 1 for c in "!#$*-0123456789?@"; 0 otherwise
 * (assuming ascii char codes, as the original implementation did)
 */
#define is_special(c) \
    ( (((unsigned int)c) - 33 < 32) \
			 && ((0xc1ff920dUL >> (((unsigned int)c) - 33)) & 1))

#define digit_val(c)    ((c) - '0')

/*
 * This file was generated by the mksyntax program.
 */

#ifdef CONFIG_ASH_OPTIMIZE_FOR_SIZE
#define USE_SIT_FUNCTION
#endif

/* number syntax index */
#define  BASESYNTAX  0  /* not in quotes */
#define  DQSYNTAX    1  /* in double quotes */
#define  SQSYNTAX    2  /* in single quotes */
#define  ARISYNTAX   3  /* in arithmetic */

#ifdef CONFIG_ASH_MATH_SUPPORT
static const char S_I_T[][4] = {
#ifdef CONFIG_ASH_ALIAS
	{CSPCL, CIGN, CIGN, CIGN},              /* 0, PEOA */
#endif
	{CSPCL, CWORD, CWORD, CWORD},           /* 1, ' ' */
	{CNL, CNL, CNL, CNL},                   /* 2, \n */
	{CWORD, CCTL, CCTL, CWORD},             /* 3, !*-/:=?[]~ */
	{CDQUOTE, CENDQUOTE, CWORD, CWORD},     /* 4, '"' */
	{CVAR, CVAR, CWORD, CVAR},              /* 5, $ */
	{CSQUOTE, CWORD, CENDQUOTE, CWORD},     /* 6, "'" */
	{CSPCL, CWORD, CWORD, CLP},             /* 7, ( */
	{CSPCL, CWORD, CWORD, CRP},             /* 8, ) */
	{CBACK, CBACK, CCTL, CBACK},            /* 9, \ */
	{CBQUOTE, CBQUOTE, CWORD, CBQUOTE},     /* 10, ` */
	{CENDVAR, CENDVAR, CWORD, CENDVAR},     /* 11, } */
#ifndef USE_SIT_FUNCTION
	{CENDFILE, CENDFILE, CENDFILE, CENDFILE},       /* 12, PEOF */
	{CWORD, CWORD, CWORD, CWORD},           /* 13, 0-9A-Za-z */
	{CCTL, CCTL, CCTL, CCTL}                /* 14, CTLESC ... */
#endif
};
#else
static const char S_I_T[][3] = {
#ifdef CONFIG_ASH_ALIAS
	{CSPCL, CIGN, CIGN},                    /* 0, PEOA */
#endif
	{CSPCL, CWORD, CWORD},                  /* 1, ' ' */
	{CNL, CNL, CNL},                        /* 2, \n */
	{CWORD, CCTL, CCTL},                    /* 3, !*-/:=?[]~ */
	{CDQUOTE, CENDQUOTE, CWORD},            /* 4, '"' */
	{CVAR, CVAR, CWORD},                    /* 5, $ */
	{CSQUOTE, CWORD, CENDQUOTE},            /* 6, "'" */
	{CSPCL, CWORD, CWORD},                  /* 7, ( */
	{CSPCL, CWORD, CWORD},                  /* 8, ) */
	{CBACK, CBACK, CCTL},                   /* 9, \ */
	{CBQUOTE, CBQUOTE, CWORD},              /* 10, ` */
	{CENDVAR, CENDVAR, CWORD},              /* 11, } */
#ifndef USE_SIT_FUNCTION
	{CENDFILE, CENDFILE, CENDFILE},         /* 12, PEOF */
	{CWORD, CWORD, CWORD},                  /* 13, 0-9A-Za-z */
	{CCTL, CCTL, CCTL}                      /* 14, CTLESC ... */
#endif
};
#endif /* CONFIG_ASH_MATH_SUPPORT */

#ifdef USE_SIT_FUNCTION

#define U_C(c) ((unsigned char)(c))

static int SIT(int c, int syntax)
{
	static const char spec_symbls[] = "\t\n !\"$&'()*-/:;<=>?[\\]`|}~";
#ifdef CONFIG_ASH_ALIAS
	static const char syntax_index_table[] = {
		1, 2, 1, 3, 4, 5, 1, 6,         /* "\t\n !\"$&'" */
		7, 8, 3, 3, 3, 3, 1, 1,         /* "()*-/:;<" */
		3, 1, 3, 3, 9, 3, 10, 1,        /* "=>?[\\]`|" */
		11, 3                           /* "}~" */
	};
#else
	static const char syntax_index_table[] = {
		0, 1, 0, 2, 3, 4, 0, 5,         /* "\t\n !\"$&'" */
		6, 7, 2, 2, 2, 2, 0, 0,         /* "()*-/:;<" */
		2, 0, 2, 2, 8, 2, 9, 0,         /* "=>?[\\]`|" */
		10, 2                           /* "}~" */
	};
#endif
	const char *s;
	int indx;

	if (c == PEOF)          /* 2^8+2 */
		return CENDFILE;
#ifdef CONFIG_ASH_ALIAS
	if (c == PEOA)          /* 2^8+1 */
		indx = 0;
	else
#endif
		if (U_C(c) >= U_C(CTLESC) && U_C(c) <= U_C(CTLQUOTEMARK))
			return CCTL;
	else {
		s = strchr(spec_symbls, c);
		if (s == 0 || *s == 0)
			return CWORD;
		indx = syntax_index_table[(s - spec_symbls)];
	}
	return S_I_T[indx][syntax];
}

#else                                                   /* USE_SIT_FUNCTION */

#define SIT(c, syntax) S_I_T[(int)syntax_index_table[((int)c)+SYNBASE]][syntax]

#ifdef CONFIG_ASH_ALIAS
#define CSPCL_CIGN_CIGN_CIGN                           0
#define CSPCL_CWORD_CWORD_CWORD                        1
#define CNL_CNL_CNL_CNL                                2
#define CWORD_CCTL_CCTL_CWORD                          3
#define CDQUOTE_CENDQUOTE_CWORD_CWORD                  4
#define CVAR_CVAR_CWORD_CVAR                           5
#define CSQUOTE_CWORD_CENDQUOTE_CWORD                  6
#define CSPCL_CWORD_CWORD_CLP                          7
#define CSPCL_CWORD_CWORD_CRP                          8
#define CBACK_CBACK_CCTL_CBACK                         9
#define CBQUOTE_CBQUOTE_CWORD_CBQUOTE                 10
#define CENDVAR_CENDVAR_CWORD_CENDVAR                 11
#define CENDFILE_CENDFILE_CENDFILE_CENDFILE           12
#define CWORD_CWORD_CWORD_CWORD                       13
#define CCTL_CCTL_CCTL_CCTL                           14
#else
#define CSPCL_CWORD_CWORD_CWORD                        0
#define CNL_CNL_CNL_CNL                                1
#define CWORD_CCTL_CCTL_CWORD                          2
#define CDQUOTE_CENDQUOTE_CWORD_CWORD                  3
#define CVAR_CVAR_CWORD_CVAR                           4
#define CSQUOTE_CWORD_CENDQUOTE_CWORD                  5
#define CSPCL_CWORD_CWORD_CLP                          6
#define CSPCL_CWORD_CWORD_CRP                          7
#define CBACK_CBACK_CCTL_CBACK                         8
#define CBQUOTE_CBQUOTE_CWORD_CBQUOTE                  9
#define CENDVAR_CENDVAR_CWORD_CENDVAR                 10
#define CENDFILE_CENDFILE_CENDFILE_CENDFILE           11
#define CWORD_CWORD_CWORD_CWORD                       12
#define CCTL_CCTL_CCTL_CCTL                           13
#endif

static const char syntax_index_table[258] = {
	/* BASESYNTAX_DQSYNTAX_SQSYNTAX_ARISYNTAX */
	/*   0  PEOF */      CENDFILE_CENDFILE_CENDFILE_CENDFILE,
#ifdef CONFIG_ASH_ALIAS
	/*   1  PEOA */      CSPCL_CIGN_CIGN_CIGN,
#endif