Import sources from 2011-03-30 iso image

1 files changed, 623 insertions, 0 deletions

diff --git a/sys/src/cmd/cpp/lex.c b/sys/src/cmd/cpp/lex.c
new file mode 100755
index 000000000..30367c3f7
--- /dev/null
+++ b/sys/src/cmd/cpp/lex.c
@@ -0,0 +1,623 @@
+#include <u.h>
+#include <libc.h>
+#include <stdio.h>
+#include "cpp.h"
+
+/*
+ * lexical FSM encoding
+ *   when in state state, and one of the characters
+ *   in ch arrives, enter nextstate.
+ *   States >= S_SELF are either final, or at least require special action.
+ *   In 'fsm' there is a line for each state X charset X nextstate.
+ *   List chars that overwrite previous entries later (e.g. C_ALPH
+ *   can be overridden by '_' by a later entry; and C_XX is the
+ *   the universal set, and should always be first.
+ *   States above S_SELF are represented in the big table as negative values.
+ *   S_SELF and S_SELFB encode the resulting token type in the upper bits.
+ *   These actions differ in that S_SELF doesn't have a lookahead char,
+ *   S_SELFB does.
+ *
+ *   The encoding is blown out into a big table for time-efficiency.
+ *   Entries have
+ *      nextstate: 6 bits; ?\ marker: 1 bit; tokentype: 9 bits.
+ */
+
+#define	MAXSTATE 32
+#define	ACT(tok,act)	((tok<<7)+act)
+#define	QBSBIT	0100
+#define	GETACT(st)	(st>>7)&0x1ff
+
+#define	UTF2(c)		((c)>=0xA0 && (c)<0xE0)		/* 2-char UTF seq */
+#define	UTF3(c)		((c)>=0xE0 && (c)<0xF0)		/* 3-char UTF seq */
+
+/* character classes */
+#define	C_WS	1
+#define	C_ALPH	2
+#define	C_NUM	3
+#define	C_EOF	4
+#define	C_XX	5
+
+enum state {
+	START=0, NUM1, NUM2, NUM3, ID1, ST1, ST2, ST3, COM1, COM2, COM3, COM4,
+	CC1, CC2, WS1, PLUS1, MINUS1, STAR1, SLASH1, PCT1, SHARP1,
+	CIRC1, GT1, GT2, LT1, LT2, OR1, AND1, ASG1, NOT1, DOTS1,
+	S_SELF=MAXSTATE, S_SELFB, S_EOF, S_NL, S_EOFSTR,
+	S_STNL, S_COMNL, S_EOFCOM, S_COMMENT, S_EOB, S_WS, S_NAME
+};
+
+int	tottok;
+int	tokkind[256];
+struct	fsm {
+	int	state;		/* if in this state */
+	uchar	ch[4];		/* and see one of these characters */
+	int	nextstate;	/* enter this state if +ve */
+};
+
+/*const*/ struct fsm fsm[] = {
+	/* start state */
+	START,	{ C_XX },	ACT(UNCLASS,S_SELF),
+	START,	{ ' ', '\t', '\v', '\r' },	WS1,
+	START,	{ C_NUM },	NUM1,
+	START,	{ '.' },	NUM3,
+	START,	{ C_ALPH },	ID1,
+	START,	{ 'L' },	ST1,
+	START,	{ '"' },	ST2,
+	START,	{ '\'' },	CC1,
+	START,	{ '/' },	COM1,
+	START,	{ EOFC },	S_EOF,
+	START,	{ '\n' },	S_NL,
+	START,	{ '-' },	MINUS1,
+	START,	{ '+' },	PLUS1,
+	START,	{ '<' },	LT1,
+	START,	{ '>' },	GT1,
+	START,	{ '=' },	ASG1,
+	START,	{ '!' },	NOT1,
+	START,	{ '&' },	AND1,
+	START,	{ '|' },	OR1,
+	START,	{ '#' },	SHARP1,
+	START,	{ '%' },	PCT1,
+	START,	{ '[' },	ACT(SBRA,S_SELF),
+	START,	{ ']' },	ACT(SKET,S_SELF),
+	START,	{ '(' },	ACT(LP,S_SELF),
+	START,	{ ')' },	ACT(RP,S_SELF),
+	START,	{ '*' },	STAR1,
+	START,	{ ',' },	ACT(COMMA,S_SELF),
+	START,	{ '?' },	ACT(QUEST,S_SELF),
+	START,	{ ':' },	ACT(COLON,S_SELF),
+	START,	{ ';' },	ACT(SEMIC,S_SELF),
+	START,	{ '{' },	ACT(CBRA,S_SELF),
+	START,	{ '}' },	ACT(CKET,S_SELF),
+	START,	{ '~' },	ACT(TILDE,S_SELF),
+	START,	{ '^' },	CIRC1,
+
+	/* saw a digit */
+	NUM1,	{ C_XX },	ACT(NUMBER,S_SELFB),
+	NUM1,	{ C_NUM, C_ALPH, '.' },	NUM1,
+	NUM1,	{ 'E', 'e' },	NUM2,
+	NUM1,	{ '_' },	ACT(NUMBER,S_SELFB),
+
+	/* saw possible start of exponent, digits-e */
+	NUM2,	{ C_XX },	ACT(NUMBER,S_SELFB),
+	NUM2,	{ '+', '-' },	NUM1,
+	NUM2,	{ C_NUM, C_ALPH },	NUM1,
+	NUM2,	{ '_' },	ACT(NUMBER,S_SELFB),
+
+	/* saw a '.', which could be a number or an operator */
+	NUM3,	{ C_XX },	ACT(DOT,S_SELFB),
+	NUM3,	{ '.' },	DOTS1,
+	NUM3,	{ C_NUM },	NUM1,
+
+	DOTS1,	{ C_XX },	ACT(UNCLASS, S_SELFB),
+	DOTS1,	{ C_NUM },	NUM1,
+	DOTS1,	{ '.' },	ACT(ELLIPS, S_SELF),
+
+	/* saw a letter or _ */
+	ID1,	{ C_XX },	ACT(NAME,S_NAME),
+	ID1,	{ C_ALPH, C_NUM },	ID1,
+
+	/* saw L (start of wide string?) */
+	ST1,	{ C_XX },	ACT(NAME,S_NAME),
+	ST1,	{ C_ALPH, C_NUM },	ID1,
+	ST1,	{ '"' },	ST2,
+	ST1,	{ '\'' },	CC1,
+
+	/* saw " beginning string */
+	ST2,	{ C_XX },	ST2,
+	ST2,	{ '"' },	ACT(STRING, S_SELF),
+	ST2,	{ '\\' },	ST3,
+	ST2,	{ '\n' },	S_STNL,
+	ST2,	{ EOFC },	S_EOFSTR,
+
+	/* saw \ in string */
+	ST3,	{ C_XX },	ST2,
+	ST3,	{ '\n' },	S_STNL,
+	ST3,	{ EOFC },	S_EOFSTR,
+
+	/* saw ' beginning character const */
+	CC1,	{ C_XX },	CC1,
+	CC1,	{ '\'' },	ACT(CCON, S_SELF),
+	CC1,	{ '\\' },	CC2,
+	CC1,	{ '\n' },	S_STNL,
+	CC1,	{ EOFC },	S_EOFSTR,
+
+	/* saw \ in ccon */
+	CC2,	{ C_XX },	CC1,
+	CC2,	{ '\n' },	S_STNL,
+	CC2,	{ EOFC },	S_EOFSTR,
+
+	/* saw /, perhaps start of comment */
+	COM1,	{ C_XX },	ACT(SLASH, S_SELFB),
+	COM1,	{ '=' },	ACT(ASSLASH, S_SELF),
+	COM1,	{ '*' },	COM2,
+	COM1,	{ '/' },	COM4,
+
+	/* saw "/*", start of comment */
+	COM2,	{ C_XX },	COM2,
+	COM2,	{ '\n' },	S_COMNL,
+	COM2,	{ '*' },	COM3,
+	COM2,	{ EOFC },	S_EOFCOM,
+
+	/* saw the * possibly ending a comment */
+	COM3,	{ C_XX },	COM2,
+	COM3,	{ '\n' },	S_COMNL,
+	COM3,	{ '*' },	COM3,
+	COM3,	{ '/' },	S_COMMENT,
+	COM3,	{ EOFC },	S_EOFCOM,
+
+	/* // comment */
+	COM4,	{ C_XX },	COM4,
+	COM4,	{ '\n' },	S_NL,
+	COM4,	{ EOFC },	S_EOFCOM,
+
+	/* saw white space, eat it up */
+	WS1,	{ C_XX },	S_WS,
+	WS1,	{ ' ', '\t', '\v', '\r'},	WS1,
+
+	/* saw -, check --, -=, -> */
+	MINUS1,	{ C_XX },	ACT(MINUS, S_SELFB),
+	MINUS1,	{ '-' },	ACT(MMINUS, S_SELF),
+	MINUS1,	{ '=' },	ACT(ASMINUS,S_SELF),
+	MINUS1,	{ '>' },	ACT(ARROW,S_SELF),
+
+	/* saw +, check ++, += */
+	PLUS1,	{ C_XX },	ACT(PLUS, S_SELFB),
+	PLUS1,	{ '+' },	ACT(PPLUS, S_SELF),
+	PLUS1,	{ '=' },	ACT(ASPLUS, S_SELF),
+
+	/* saw <, check <<, <<=, <= */
+	LT1,	{ C_XX },	ACT(LT, S_SELFB),
+	LT1,	{ '<' },	LT2,
+	LT1,	{ '=' },	ACT(LEQ, S_SELF),
+	LT2,	{ C_XX },	ACT(LSH, S_SELFB),
+	LT2,	{ '=' },	ACT(ASLSH, S_SELF),
+
+	/* saw >, check >>, >>=, >= */
+	GT1,	{ C_XX },	ACT(GT, S_SELFB),
+	GT1,	{ '>' },	GT2,
+	GT1,	{ '=' },	ACT(GEQ, S_SELF),
+	GT2,	{ C_XX },	ACT(RSH, S_SELFB),
+	GT2,	{ '=' },	ACT(ASRSH, S_SELF),
+
+	/* = */
+	ASG1,	{ C_XX },	ACT(ASGN, S_SELFB),
+	ASG1,	{ '=' },	ACT(EQ, S_SELF),
+
+	/* ! */
+	NOT1,	{ C_XX },	ACT(NOT, S_SELFB),
+	NOT1,	{ '=' },	ACT(NEQ, S_SELF),
+
+	/* & */
+	AND1,	{ C_XX },	ACT(AND, S_SELFB),
+	AND1,	{ '&' },	ACT(LAND, S_SELF),
+	AND1,	{ '=' },	ACT(ASAND, S_SELF),
+
+	/* | */
+	OR1,	{ C_XX },	ACT(OR, S_SELFB),
+	OR1,	{ '|' },	ACT(LOR, S_SELF),
+	OR1,	{ '=' },	ACT(ASOR, S_SELF),
+
+	/* # */
+	SHARP1,	{ C_XX },	ACT(SHARP, S_SELFB),
+	SHARP1,	{ '#' },	ACT(DSHARP, S_SELF),
+
+	/* % */
+	PCT1,	{ C_XX },	ACT(PCT, S_SELFB),
+	PCT1,	{ '=' },	ACT(ASPCT, S_SELF),
+
+	/* * */
+	STAR1,	{ C_XX },	ACT(STAR, S_SELFB),
+	STAR1,	{ '=' },	ACT(ASSTAR, S_SELF),
+
+	/* ^ */
+	CIRC1,	{ C_XX },	ACT(CIRC, S_SELFB),
+	CIRC1,	{ '=' },	ACT(ASCIRC, S_SELF),
+
+	-1
+};
+
+/* first index is char, second is state */
+/* increase #states to power of 2 to encourage use of shift */
+short	bigfsm[256][MAXSTATE];
+
+void
+expandlex(void)
+{
+	/*const*/ struct fsm *fp;
+	int i, j, nstate;
+
+	for (fp = fsm; fp->state>=0; fp++) {
+		for (i=0; fp->ch[i]; i++) {
+			nstate = fp->nextstate;
+			if (nstate >= S_SELF)
+				nstate = ~nstate;
+			switch (fp->ch[i]) {
+
+			case C_XX:		/* random characters */
+				for (j=0; j<256; j++)
+					bigfsm[j][fp->state] = nstate;
+				continue;
+			case C_ALPH:
+				for (j=0; j<=256; j++)
+					if ('a'<=j&&j<='z' || 'A'<=j&&j<='Z'
+					  || UTF2(j) || UTF3(j) || j=='_')
+						bigfsm[j][fp->state] = nstate;
+				continue;
+			case C_NUM:
+				for (j='0'; j<='9'; j++)
+					bigfsm[j][fp->state] = nstate;
+				continue;
+			default:
+				bigfsm[fp->ch[i]][fp->state] = nstate;
+			}
+		}
+	}
+	/* install special cases for ? (trigraphs),  \ (splicing), runes, and EOB */
+	for (i=0; i<MAXSTATE; i++) {
+		for (j=0; j<0xFF; j++)
+			if (j=='?' || j=='\\' || UTF2(j) || UTF3(j)) {
+				if (bigfsm[j][i]>0)
+					bigfsm[j][i] = ~bigfsm[j][i];
+				bigfsm[j][i] &= ~QBSBIT;
+			}
+		bigfsm[EOB][i] = ~S_EOB;
+		if (bigfsm[EOFC][i]>=0)
+			bigfsm[EOFC][i] = ~S_EOF;
+	}
+}
+
+void
+fixlex(void)
+{
+	/* do C++ comments? */
+	if (Cplusplus==0)
+		bigfsm['/'][COM1] = bigfsm['x'][COM1];
+}
+
+/*
+ * fill in a row of tokens from input, terminated by NL or END
+ * First token is put at trp->lp.
+ * Reset is non-zero when the input buffer can be "rewound."
+ * The value is a flag indicating that possible macros have
+ * been seen in the row.
+ */
+int
+gettokens(Tokenrow *trp, int reset)
+{
+	register int c, state, oldstate;
+	register uchar *ip;
+	register Token *tp, *maxp;
+	int runelen;
+	Source *s = cursource;
+	int nmac = 0;
+	extern char outbuf[];
+
+	tp = trp->lp;
+	ip = s->inp;
+	if (reset) {
+		s->lineinc = 0;
+		if (ip>=s->inl) {		/* nothing in buffer */
+			s->inl = s->inb;
+			fillbuf(s);
+			ip = s->inp = s->inb;
+		} else if (ip >= s->inb+(3*s->ins/4)) {
+			memmove(s->inb, ip, 4+s->inl-ip);
+			s->inl = s->inb+(s->inl-ip);
+			ip = s->inp = s->inb;
+		}
+	}
+	maxp = &trp->bp[trp->max];
+	runelen = 1;
+	for (;;) {
+	   continue2:
+		if (tp>=maxp) {
+			trp->lp = tp;
+			tp = growtokenrow(trp);
+			maxp = &trp->bp[trp->max];
+		}
+		tp->type = UNCLASS;
+		tp->hideset = 0;
+		tp->t = ip;
+		tp->wslen = 0;
+		tp->flag = 0;
+		state = START;
+		for (;;) {
+			oldstate = state;
+			c = *ip;
+			if ((state = bigfsm[c][state]) >= 0) {
+				ip += runelen;
+				runelen = 1;
+				continue;
+			}
+			state = ~state;
+		reswitch:
+			switch (state&0177) {
+			case S_SELF:
+				ip += runelen;
+				runelen = 1;
+			case S_SELFB:
+				tp->type = GETACT(state);
+				tp->len = ip - tp->t;
+				tp++;
+				goto continue2;
+
+			case S_NAME:	/* like S_SELFB but with nmac check */
+				tp->type = NAME;
+				tp->len = ip - tp->t;
+				nmac |= quicklook(tp->t[0], tp->len>1?tp->t[1]:0);
+				tp++;
+				goto continue2;
+
+			case S_WS:
+				tp->wslen = ip - tp->t;
+				tp->t = ip;
+				state = START;
+				continue;
+
+			default:
+				if ((state&QBSBIT)==0) {
+					ip += runelen;
+					runelen = 1;
+					continue;
+				}
+				state &= ~QBSBIT;
+				s->inp = ip;
+				if (c=='?') { 	/* check trigraph */
+					if (trigraph(s)) {
+						state = oldstate;
+						continue;
+					}
+					goto reswitch;
+				}
+				if (c=='\\') { /* line-folding */
+					if (foldline(s)) {
+						s->lineinc++;
+						state = oldstate;
+						continue;
+					}
+					goto reswitch;
+				}
+				if (UTF2(c)) {
+					runelen = 2;
+					goto reswitch;
+				}
+				if (UTF3(c)) {
+					runelen = 3;
+					goto reswitch;
+				}
+				error(WARNING, "Lexical botch in cpp");
+				ip += runelen;
+				runelen = 1;
+				continue;
+
+			case S_EOB:
+				s->inp = ip;
+				fillbuf(cursource);
+				state = oldstate;
+				continue;
+
+			case S_EOF:
+				tp->type = END;
+				tp->len = 0;
+				s->inp = ip;
+				if (tp!=trp->bp && (tp-1)->type!=NL && cursource->fd!=-1)
+					error(WARNING,"No newline at end of file");
+				trp->lp = tp+1;
+				return nmac;
+
+			case S_STNL:
+				error(ERROR, "Unterminated string or char const");
+			case S_NL:
+				tp->t = ip;
+				tp->type = NL;
+				tp->len = 1;
+				tp->wslen = 0;
+				s->lineinc++;
+				s->inp = ip+1;
+				trp->lp = tp+1;
+				return nmac;
+
+			case S_EOFSTR:
+				error(FATAL, "EOF in string or char constant");
+				break;
+
+			case S_COMNL:
+				s->lineinc++;
+				state = COM2;
+				ip += runelen;
+				runelen = 1;
+ 				if (ip >= s->inb+(7*s->ins/8)) { /* very long comment */
+					memmove(tp->t, ip, 4+s->inl-ip);
+					s->inl -= ip-tp->t;
+					ip = tp->t+1;
+				}
+				continue;
+
+			case S_EOFCOM:
+				error(WARNING, "EOF inside comment");
+				--ip;
+			case S_COMMENT:
+				++ip;
+				tp->t = ip;
+				tp->t[-1] = ' ';
+				tp->wslen = 1;
+				state = START;
+				continue;
+			}
+			break;
+		}
+		ip += runelen;
+		runelen = 1;
+		tp->len = ip - tp->t;
+		tp++;
+	}
+}
+
+/* have seen ?; handle the trigraph it starts (if any) else 0 */
+int
+trigraph(Source *s)
+{
+	int c;
+
+	while (s->inp+2 >= s->inl && fillbuf(s)!=EOF)
+		;
+	if (s->inp[1]!='?')
+		return 0;
+	c = 0;
+	switch(s->inp[2]) {
+	case '=':
+		c = '#'; break;
+	case '(':
+		c = '['; break;
+	case '/':
+		c = '\\'; break;
+	case ')':
+		c = ']'; break;
+	case '\'':
+		c = '^'; break;
+	case '<':
+		c = '{'; break;
+	case '!':
+		c = '|'; break;
+	case '>':
+		c = '}'; break;
+	case '-':
+		c = '~'; break;
+	}
+	if (c) {
+		*s->inp = c;
+		memmove(s->inp+1, s->inp+3, s->inl-s->inp+2);
+		s->inl -= 2;
+	}
+	return c;
+}
+
+int
+foldline(Source *s)
+{
+	int ncr = 0;
+
+recheck:
+	while (s->inp+1 >= s->inl && fillbuf(s)!=EOF)
+		;
+	if (s->inp[ncr+1] == '\r') {	/* nonstandardly, ignore CR before line-folding */
+		ncr++;
+		goto recheck;
+	}
+	if (s->inp[ncr+1] == '\n') {
+		memmove(s->inp, s->inp+2+ncr, s->inl-s->inp+3-ncr);
+		s->inl -= 2+ncr;
+		return 1;
+	}
+	return 0;
+}
+
+int
+fillbuf(Source *s)
+{
+	int n;
+
+	while((char *)s->inl+s->ins/8 > (char *)s->inb+s->ins) {
+		int l = s->inl - s->inb;
+		int p = s->inp - s->inb;
+		if(l < 0) 
+			error(FATAL, "negative end of input!?");
+		if(p < 0)
+			error(FATAL, "negative input pointer!?");
+		/* double the buffer size and try again */
+		s->ins *= 2;
+		s->inb = dorealloc(s->inb, s->ins);
+		s->inl = s->inb + l;
+		s->inp = s->inb + p;
+	}
+	if (s->fd<0 || (n=read(s->fd, (char *)s->inl, s->ins/8)) <= 0)
+		n = 0;
+	if ((*s->inp&0xff) == EOB) /* sentinel character appears in input */
+		*s->inp = EOFC;
+	s->inl += n;
+	s->inl[0] = s->inl[1]= s->inl[2]= s->inl[3] = EOB;
+	if (n==0) {
+		s->inl[0] = s->inl[1]= s->inl[2]= s->inl[3] = EOFC;
+		return EOF;
+	}
+	return 0;
+}
+
+/*
+ * Push down to new source of characters.
+ * If fd>0 and str==NULL, then from a file `name';
+ * if fd==-1 and str, then from the string.
+ */
+Source *
+setsource(char *name, int fd, char *str)
+{
+	Source *s = new(Source);
+	int len;
+
+	s->line = 1;
+	s->lineinc = 0;
+	s->fd = fd;
+	s->filename = name;
+	s->next = cursource;
+	s->ifdepth = 0;
+	cursource = s;
+	/* slop at right for EOB */
+	if (str) {
+		len = strlen(str);
+		s->inb = domalloc(len+4);
+		s->inp = s->inb;
+		strncpy((char *)s->inp, str, len);
+	} else {
+		Dir *d;
+		int junk;
+		ulong length = 0;
+		d = dirfstat(fd);
+		if (d != nil) {
+			length = d->length;
+			free(d);
+		}
+		junk = length;
+		if (junk<INS)
+			junk = INS;
+		s->inb = domalloc((junk)+4);
+		s->inp = s->inb;
+		len = 0;
+	}
+
+	s->ins = INS;	
+	s->inl = s->inp+len;
+	s->inl[0] = s->inl[1] = EOB;
+	return s;
+}
+
+void
+unsetsource(void)
+{
+	Source *s = cursource;
+
+	if (s->fd>=0) {
+		close(s->fd);
+		dofree(s->inb);
+	}
+	cursource = s->next;
+	dofree(s);
+}