/
lex.c
2414 lines (2155 loc) · 46.7 KB
/
lex.c
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// Copyright 2009 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include <u.h>
#include <libc.h>
#include "go.h"
#include "y.tab.h"
#include <ar.h>
#undef getc
#undef ungetc
#define getc ccgetc
#define ungetc ccungetc
extern int yychar;
int yyprev;
int yylast;
static void lexinit(void);
static void lexinit1(void);
static void lexfini(void);
static void yytinit(void);
static int getc(void);
static void ungetc(int);
static int32 getr(void);
static int escchar(int, int*, vlong*);
static void addidir(char*);
static int getlinepragma(void);
static char *goos, *goarch, *goroot;
#define BOM 0xFEFF
// Compiler experiments.
// These are controlled by the GOEXPERIMENT environment
// variable recorded when the compiler is built.
static struct {
char *name;
int *val;
} exper[] = {
// {"rune32", &rune32},
{"fieldtrack", &fieldtrack_enabled},
{"precisestack", &precisestack_enabled},
{nil, nil},
};
// Debug arguments.
// These can be specified with the -d flag, as in "-d nil"
// to set the debug_checknil variable. In general the list passed
// to -d can be comma-separated.
static struct {
char *name;
int *val;
} debugtab[] = {
{"nil", &debug_checknil},
{nil, nil},
};
static void
addexp(char *s)
{
int i;
for(i=0; exper[i].name != nil; i++) {
if(strcmp(exper[i].name, s) == 0) {
*exper[i].val = 1;
return;
}
}
print("unknown experiment %s\n", s);
exits("unknown experiment");
}
static void
setexp(void)
{
char *f[20];
int i, nf;
precisestack_enabled = 1; // on by default
// cmd/dist #defines GOEXPERIMENT for us.
nf = getfields(GOEXPERIMENT, f, nelem(f), 1, ",");
for(i=0; i<nf; i++)
addexp(f[i]);
}
char*
expstring(void)
{
int i;
static char buf[512];
strcpy(buf, "X");
for(i=0; exper[i].name != nil; i++)
if(*exper[i].val)
seprint(buf+strlen(buf), buf+sizeof buf, ",%s", exper[i].name);
if(strlen(buf) == 1)
strcpy(buf, "X,none");
buf[1] = ':';
return buf;
}
// Our own isdigit, isspace, isalpha, isalnum that take care
// of EOF and other out of range arguments.
static int
yy_isdigit(int c)
{
return c >= 0 && c <= 0xFF && isdigit(c);
}
static int
yy_isspace(int c)
{
return c == ' ' || c == '\t' || c == '\n' || c == '\r';
}
static int
yy_isalpha(int c)
{
return c >= 0 && c <= 0xFF && isalpha(c);
}
static int
yy_isalnum(int c)
{
return c >= 0 && c <= 0xFF && isalnum(c);
}
// Disallow use of isdigit etc.
#undef isdigit
#undef isspace
#undef isalpha
#undef isalnum
#define isdigit use_yy_isdigit_instead_of_isdigit
#define isspace use_yy_isspace_instead_of_isspace
#define isalpha use_yy_isalpha_instead_of_isalpha
#define isalnum use_yy_isalnum_instead_of_isalnum
#define DBG if(!debug['x']){}else print
/*c2go void DBG(char*, ...); */
enum
{
EOF = -1,
};
void
usage(void)
{
print("usage: %cg [options] file.go...\n", thechar);
flagprint(1);
exits("usage");
}
void
fault(int s)
{
USED(s);
// If we've already complained about things
// in the program, don't bother complaining
// about the seg fault too; let the user clean up
// the code and try again.
if(nsavederrors + nerrors > 0)
errorexit();
fatal("fault");
}
#ifdef PLAN9
void
catcher(void *v, char *s)
{
USED(v);
if(strncmp(s, "sys: trap: fault read", 21) == 0) {
if(nsavederrors + nerrors > 0)
errorexit();
fatal("fault");
}
noted(NDFLT);
}
#endif
void
doversion(void)
{
char *p;
p = expstring();
if(strcmp(p, "X:none") == 0)
p = "";
print("%cg version %s%s%s\n", thechar, getgoversion(), *p ? " " : "", p);
exits(0);
}
int
main(int argc, char *argv[])
{
int i;
NodeList *l;
char *p;
#ifdef SIGBUS
signal(SIGBUS, fault);
signal(SIGSEGV, fault);
#endif
#ifdef PLAN9
notify(catcher);
// Tell the FPU to handle all exceptions.
setfcr(FPPDBL|FPRNR);
#endif
// Allow GOARCH=thestring or GOARCH=thestringsuffix,
// but not other values.
p = getgoarch();
if(strncmp(p, thestring, strlen(thestring)) != 0)
sysfatal("cannot use %cg with GOARCH=%s", thechar, p);
goarch = p;
linkarchinit();
ctxt = linknew(thelinkarch);
ctxt->diag = yyerror;
ctxt->bso = &bstdout;
Binit(&bstdout, 1, OWRITE);
localpkg = mkpkg(strlit(""));
localpkg->prefix = "\"\"";
// pseudo-package, for scoping
builtinpkg = mkpkg(strlit("go.builtin"));
// pseudo-package, accessed by import "unsafe"
unsafepkg = mkpkg(strlit("unsafe"));
unsafepkg->name = "unsafe";
// real package, referred to by generated runtime calls
runtimepkg = mkpkg(strlit("runtime"));
runtimepkg->name = "runtime";
// pseudo-packages used in symbol tables
gostringpkg = mkpkg(strlit("go.string"));
gostringpkg->name = "go.string";
gostringpkg->prefix = "go.string"; // not go%2estring
itabpkg = mkpkg(strlit("go.itab"));
itabpkg->name = "go.itab";
itabpkg->prefix = "go.itab"; // not go%2eitab
weaktypepkg = mkpkg(strlit("go.weak.type"));
weaktypepkg->name = "go.weak.type";
weaktypepkg->prefix = "go.weak.type"; // not go%2eweak%2etype
typelinkpkg = mkpkg(strlit("go.typelink"));
typelinkpkg->name = "go.typelink";
typelinkpkg->prefix = "go.typelink"; // not go%2etypelink
trackpkg = mkpkg(strlit("go.track"));
trackpkg->name = "go.track";
trackpkg->prefix = "go.track"; // not go%2etrack
typepkg = mkpkg(strlit("type"));
typepkg->name = "type";
goroot = getgoroot();
goos = getgoos();
nacl = strcmp(goos, "nacl") == 0;
if(nacl)
flag_largemodel = 1;
setexp();
outfile = nil;
flagcount("+", "compiling runtime", &compiling_runtime);
flagcount("%", "debug non-static initializers", &debug['%']);
flagcount("A", "for bootstrapping, allow 'any' type", &debug['A']);
flagcount("B", "disable bounds checking", &debug['B']);
flagstr("D", "path: set relative path for local imports", &localimport);
flagcount("E", "debug symbol export", &debug['E']);
flagfn1("I", "dir: add dir to import search path", addidir);
flagcount("K", "debug missing line numbers", &debug['K']);
flagcount("L", "use full (long) path in error messages", &debug['L']);
flagcount("M", "debug move generation", &debug['M']);
flagcount("N", "disable optimizations", &debug['N']);
flagcount("P", "debug peephole optimizer", &debug['P']);
flagcount("R", "debug register optimizer", &debug['R']);
flagcount("S", "print assembly listing", &debug['S']);
flagfn0("V", "print compiler version", doversion);
flagcount("W", "debug parse tree after type checking", &debug['W']);
flagcount("complete", "compiling complete package (no C or assembly)", &pure_go);
flagstr("d", "list: print debug information about items in list", &debugstr);
flagcount("e", "no limit on number of errors reported", &debug['e']);
flagcount("f", "debug stack frames", &debug['f']);
flagcount("g", "debug code generation", &debug['g']);
flagcount("h", "halt on error", &debug['h']);
flagcount("i", "debug line number stack", &debug['i']);
flagstr("installsuffix", "pkg directory suffix", &flag_installsuffix);
flagcount("j", "debug runtime-initialized variables", &debug['j']);
flagcount("l", "disable inlining", &debug['l']);
flagcount("live", "debug liveness analysis", &debuglive);
flagcount("m", "print optimization decisions", &debug['m']);
flagcount("nolocalimports", "reject local (relative) imports", &nolocalimports);
flagstr("o", "obj: set output file", &outfile);
flagstr("p", "path: set expected package import path", &myimportpath);
flagcount("pack", "write package file instead of object file", &writearchive);
flagcount("r", "debug generated wrappers", &debug['r']);
flagcount("race", "enable race detector", &flag_race);
flagcount("s", "warn about composite literals that can be simplified", &debug['s']);
flagstr("trimpath", "prefix: remove prefix from recorded source file paths", &ctxt->trimpath);
flagcount("u", "reject unsafe code", &safemode);
flagcount("v", "increase debug verbosity", &debug['v']);
flagcount("w", "debug type checking", &debug['w']);
use_writebarrier = 1;
flagcount("wb", "enable write barrier", &use_writebarrier);
flagcount("x", "debug lexer", &debug['x']);
flagcount("y", "debug declarations in canned imports (with -d)", &debug['y']);
if(thechar == '6')
flagcount("largemodel", "generate code that assumes a large memory model", &flag_largemodel);
flagparse(&argc, &argv, usage);
ctxt->debugasm = debug['S'];
ctxt->debugvlog = debug['v'];
if(argc < 1)
usage();
if(flag_race) {
racepkg = mkpkg(strlit("runtime/race"));
racepkg->name = "race";
}
// parse -d argument
if(debugstr) {
char *f[100];
int i, j, nf;
nf = getfields(debugstr, f, nelem(f), 1, ",");
for(i=0; i<nf; i++) {
for(j=0; debugtab[j].name != nil; j++) {
if(strcmp(debugtab[j].name, f[i]) == 0) {
*debugtab[j].val = 1;
break;
}
}
if(debugtab[j].name == nil)
sysfatal("unknown debug information -d '%s'\n", f[i]);
}
}
// enable inlining. for now:
// default: inlining on. (debug['l'] == 1)
// -l: inlining off (debug['l'] == 0)
// -ll, -lll: inlining on again, with extra debugging (debug['l'] > 1)
if(debug['l'] <= 1)
debug['l'] = 1 - debug['l'];
if(thechar == '8') {
p = getgo386();
if(strcmp(p, "387") == 0)
use_sse = 0;
else if(strcmp(p, "sse2") == 0)
use_sse = 1;
else
sysfatal("unsupported setting GO386=%s", p);
}
fmtinstallgo();
betypeinit();
if(widthptr == 0)
fatal("betypeinit failed");
lexinit();
typeinit();
lexinit1();
yytinit();
blockgen = 1;
dclcontext = PEXTERN;
nerrors = 0;
lexlineno = 1;
for(i=0; i<argc; i++) {
infile = argv[i];
linehist(infile, 0, 0);
curio.infile = infile;
curio.bin = Bopen(infile, OREAD);
if(curio.bin == nil) {
print("open %s: %r\n", infile);
errorexit();
}
curio.peekc = 0;
curio.peekc1 = 0;
curio.nlsemi = 0;
curio.eofnl = 0;
curio.last = 0;
// Skip initial BOM if present.
if(Bgetrune(curio.bin) != BOM)
Bungetrune(curio.bin);
block = 1;
iota = -1000000;
yyparse();
if(nsyntaxerrors != 0)
errorexit();
linehist(nil, 0, 0);
if(curio.bin != nil)
Bterm(curio.bin);
}
testdclstack();
mkpackage(localpkg->name); // final import not used checks
lexfini();
typecheckok = 1;
if(debug['f'])
frame(1);
// Process top-level declarations in phases.
// Phase 1: const, type, and names and types of funcs.
// This will gather all the information about types
// and methods but doesn't depend on any of it.
defercheckwidth();
for(l=xtop; l; l=l->next)
if(l->n->op != ODCL && l->n->op != OAS)
typecheck(&l->n, Etop);
// Phase 2: Variable assignments.
// To check interface assignments, depends on phase 1.
for(l=xtop; l; l=l->next)
if(l->n->op == ODCL || l->n->op == OAS)
typecheck(&l->n, Etop);
resumecheckwidth();
// Phase 3: Type check function bodies.
for(l=xtop; l; l=l->next) {
if(l->n->op == ODCLFUNC || l->n->op == OCLOSURE) {
curfn = l->n;
saveerrors();
typechecklist(l->n->nbody, Etop);
checkreturn(l->n);
if(nerrors != 0)
l->n->nbody = nil; // type errors; do not compile
}
}
curfn = nil;
if(nsavederrors+nerrors)
errorexit();
// Phase 4: Inlining
if(debug['l'] > 1) {
// Typecheck imported function bodies if debug['l'] > 1,
// otherwise lazily when used or re-exported.
for(l=importlist; l; l=l->next)
if (l->n->inl) {
saveerrors();
typecheckinl(l->n);
}
if(nsavederrors+nerrors)
errorexit();
}
if(debug['l']) {
// Find functions that can be inlined and clone them before walk expands them.
for(l=xtop; l; l=l->next)
if(l->n->op == ODCLFUNC)
caninl(l->n);
// Expand inlineable calls in all functions
for(l=xtop; l; l=l->next)
if(l->n->op == ODCLFUNC)
inlcalls(l->n);
}
// Phase 5: Escape analysis.
// Required for moving heap allocations onto stack,
// which in turn is required by the closure implementation,
// which stores the addresses of stack variables into the closure.
// If the closure does not escape, it needs to be on the stack
// or else the stack copier will not update it.
escapes(xtop);
// Escape analysis moved escaped values off stack.
// Move large values off stack too.
movelarge(xtop);
// Phase 6: Compile top level functions.
for(l=xtop; l; l=l->next)
if(l->n->op == ODCLFUNC)
funccompile(l->n, 0);
if(nsavederrors+nerrors == 0)
fninit(xtop);
// Phase 7: Check external declarations.
for(l=externdcl; l; l=l->next)
if(l->n->op == ONAME)
typecheck(&l->n, Erv);
if(nerrors+nsavederrors)
errorexit();
dumpobj();
if(nerrors+nsavederrors)
errorexit();
flusherrors();
exits(0);
return 0;
}
void
saveerrors(void)
{
nsavederrors += nerrors;
nerrors = 0;
}
static int
arsize(Biobuf *b, char *name)
{
struct ar_hdr a;
if(Bread(b, a.name, sizeof(a.name)) != sizeof(a.name) ||
Bread(b, a.date, sizeof(a.date)) != sizeof(a.date) ||
Bread(b, a.uid, sizeof(a.uid)) != sizeof(a.uid) ||
Bread(b, a.gid, sizeof(a.gid)) != sizeof(a.gid) ||
Bread(b, a.mode, sizeof(a.mode)) != sizeof(a.mode) ||
Bread(b, a.size, sizeof(a.size)) != sizeof(a.size) ||
Bread(b, a.fmag, sizeof(a.fmag)) != sizeof(a.fmag))
return -1;
if(strncmp(a.name, name, strlen(name)) != 0)
return -1;
return atoi(a.size);
}
static int
skiptopkgdef(Biobuf *b)
{
char *p;
int sz;
/* archive header */
if((p = Brdline(b, '\n')) == nil)
return 0;
if(Blinelen(b) != 8)
return 0;
if(memcmp(p, "!<arch>\n", 8) != 0)
return 0;
/* symbol table may be first; skip it */
sz = arsize(b, "__.GOSYMDEF");
if(sz >= 0)
Bseek(b, sz, 1);
else
Bseek(b, 8, 0);
/* package export block is next */
sz = arsize(b, "__.PKGDEF");
if(sz <= 0)
return 0;
return 1;
}
static void
addidir(char* dir)
{
Idir** pp;
if(dir == nil)
return;
for(pp = &idirs; *pp != nil; pp = &(*pp)->link)
;
*pp = mal(sizeof(Idir));
(*pp)->link = nil;
(*pp)->dir = dir;
}
// is this path a local name? begins with ./ or ../ or /
static int
islocalname(Strlit *name)
{
if(name->len >= 1 && name->s[0] == '/')
return 1;
if(ctxt->windows && name->len >= 3 &&
yy_isalpha(name->s[0]) && name->s[1] == ':' && name->s[2] == '/')
return 1;
if(name->len >= 2 && strncmp(name->s, "./", 2) == 0)
return 1;
if(name->len == 1 && strncmp(name->s, ".", 1) == 0)
return 1;
if(name->len >= 3 && strncmp(name->s, "../", 3) == 0)
return 1;
if(name->len == 2 && strncmp(name->s, "..", 2) == 0)
return 1;
return 0;
}
static int
findpkg(Strlit *name)
{
Idir *p;
char *q, *suffix, *suffixsep;
if(islocalname(name)) {
if(safemode || nolocalimports)
return 0;
// try .a before .6. important for building libraries:
// if there is an array.6 in the array.a library,
// want to find all of array.a, not just array.6.
snprint(namebuf, sizeof(namebuf), "%Z.a", name);
if(access(namebuf, 0) >= 0)
return 1;
snprint(namebuf, sizeof(namebuf), "%Z.%c", name, thechar);
if(access(namebuf, 0) >= 0)
return 1;
return 0;
}
// local imports should be canonicalized already.
// don't want to see "encoding/../encoding/base64"
// as different from "encoding/base64".
q = mal(name->len+1);
memmove(q, name->s, name->len);
q[name->len] = '\0';
cleanname(q);
if(strlen(q) != name->len || memcmp(q, name->s, name->len) != 0) {
yyerror("non-canonical import path %Z (should be %s)", name, q);
return 0;
}
for(p = idirs; p != nil; p = p->link) {
snprint(namebuf, sizeof(namebuf), "%s/%Z.a", p->dir, name);
if(access(namebuf, 0) >= 0)
return 1;
snprint(namebuf, sizeof(namebuf), "%s/%Z.%c", p->dir, name, thechar);
if(access(namebuf, 0) >= 0)
return 1;
}
if(goroot != nil) {
suffix = "";
suffixsep = "";
if(flag_installsuffix != nil) {
suffixsep = "_";
suffix = flag_installsuffix;
} else if(flag_race) {
suffixsep = "_";
suffix = "race";
}
snprint(namebuf, sizeof(namebuf), "%s/pkg/%s_%s%s%s/%Z.a", goroot, goos, goarch, suffixsep, suffix, name);
if(access(namebuf, 0) >= 0)
return 1;
snprint(namebuf, sizeof(namebuf), "%s/pkg/%s_%s%s%s/%Z.%c", goroot, goos, goarch, suffixsep, suffix, name, thechar);
if(access(namebuf, 0) >= 0)
return 1;
}
return 0;
}
static void
fakeimport(void)
{
importpkg = mkpkg(strlit("fake"));
cannedimports("fake.6", "$$\n");
}
void
importfile(Val *f, int line)
{
Biobuf *imp;
char *file, *p, *q, *tag;
int32 c;
int len;
Strlit *path;
char *cleanbuf, *prefix;
USED(line);
if(f->ctype != CTSTR) {
yyerror("import statement not a string");
fakeimport();
return;
}
if(f->u.sval->len == 0) {
yyerror("import path is empty");
fakeimport();
return;
}
if(isbadimport(f->u.sval)) {
fakeimport();
return;
}
// The package name main is no longer reserved,
// but we reserve the import path "main" to identify
// the main package, just as we reserve the import
// path "math" to identify the standard math package.
if(strcmp(f->u.sval->s, "main") == 0) {
yyerror("cannot import \"main\"");
errorexit();
}
if(myimportpath != nil && strcmp(f->u.sval->s, myimportpath) == 0) {
yyerror("import \"%Z\" while compiling that package (import cycle)", f->u.sval);
errorexit();
}
if(strcmp(f->u.sval->s, "unsafe") == 0) {
if(safemode) {
yyerror("cannot import package unsafe");
errorexit();
}
importpkg = mkpkg(f->u.sval);
cannedimports("unsafe.6", unsafeimport);
return;
}
path = f->u.sval;
if(islocalname(path)) {
if(path->s[0] == '/') {
yyerror("import path cannot be absolute path");
fakeimport();
return;
}
prefix = ctxt->pathname;
if(localimport != nil)
prefix = localimport;
cleanbuf = mal(strlen(prefix) + strlen(path->s) + 2);
strcpy(cleanbuf, prefix);
strcat(cleanbuf, "/");
strcat(cleanbuf, path->s);
cleanname(cleanbuf);
path = strlit(cleanbuf);
if(isbadimport(path)) {
fakeimport();
return;
}
}
if(!findpkg(path)) {
yyerror("can't find import: \"%Z\"", f->u.sval);
errorexit();
}
importpkg = mkpkg(path);
// If we already saw that package, feed a dummy statement
// to the lexer to avoid parsing export data twice.
if(importpkg->imported) {
file = strdup(namebuf);
tag = "";
if(importpkg->safe) {
tag = "safe";
}
p = smprint("package %s %s\n$$\n", importpkg->name, tag);
cannedimports(file, p);
return;
}
importpkg->imported = 1;
imp = Bopen(namebuf, OREAD);
if(imp == nil) {
yyerror("can't open import: \"%Z\": %r", f->u.sval);
errorexit();
}
file = strdup(namebuf);
len = strlen(namebuf);
if(len > 2 && namebuf[len-2] == '.' && namebuf[len-1] == 'a') {
if(!skiptopkgdef(imp)) {
yyerror("import %s: not a package file", file);
errorexit();
}
}
// check object header
p = Brdstr(imp, '\n', 1);
if(strcmp(p, "empty archive") != 0) {
if(strncmp(p, "go object ", 10) != 0) {
yyerror("import %s: not a go object file", file);
errorexit();
}
q = smprint("%s %s %s %s", getgoos(), getgoarch(), getgoversion(), expstring());
if(strcmp(p+10, q) != 0) {
yyerror("import %s: object is [%s] expected [%s]", file, p+10, q);
errorexit();
}
free(q);
}
// assume files move (get installed)
// so don't record the full path.
linehist(file + len - path->len - 2, -1, 1); // acts as #pragma lib
/*
* position the input right
* after $$ and return
*/
pushedio = curio;
curio.bin = imp;
curio.peekc = 0;
curio.peekc1 = 0;
curio.infile = file;
curio.nlsemi = 0;
typecheckok = 1;
for(;;) {
c = getc();
if(c == EOF)
break;
if(c != '$')
continue;
c = getc();
if(c == EOF)
break;
if(c != '$')
continue;
return;
}
yyerror("no import in \"%Z\"", f->u.sval);
unimportfile();
}
void
unimportfile(void)
{
if(curio.bin != nil) {
Bterm(curio.bin);
curio.bin = nil;
} else
lexlineno--; // re correct sys.6 line number
curio = pushedio;
pushedio.bin = nil;
incannedimport = 0;
typecheckok = 0;
}
void
cannedimports(char *file, char *cp)
{
lexlineno++; // if sys.6 is included on line 1,
pushedio = curio;
curio.bin = nil;
curio.peekc = 0;
curio.peekc1 = 0;
curio.infile = file;
curio.cp = cp;
curio.nlsemi = 0;
curio.importsafe = 0;
typecheckok = 1;
incannedimport = 1;
}
static int
isfrog(int c)
{
// complain about possibly invisible control characters
if(c < ' ') {
return !yy_isspace(c); // exclude good white space
}
if(0x7f <= c && c <= 0xa0) // DEL, unicode block including unbreakable space.
return 1;
return 0;
}
typedef struct Loophack Loophack;
struct Loophack {
int v;
Loophack *next;
};
static int32
_yylex(void)
{
int c, c1, clen, escflag, ncp;
vlong v;
char *cp, *ep;
Rune rune;
Sym *s;
static Loophack *lstk;
Loophack *h;
prevlineno = lineno;
l0:
c = getc();
if(yy_isspace(c)) {
if(c == '\n' && curio.nlsemi) {
ungetc(c);
DBG("lex: implicit semi\n");
return ';';
}
goto l0;
}
lineno = lexlineno; /* start of token */
if(c >= Runeself) {
/* all multibyte runes are alpha */
cp = lexbuf;
ep = lexbuf+sizeof lexbuf;
goto talph;
}
if(yy_isalpha(c)) {
cp = lexbuf;
ep = lexbuf+sizeof lexbuf;
goto talph;
}
if(yy_isdigit(c))
goto tnum;
switch(c) {
case EOF:
lineno = prevlineno;
ungetc(EOF);
return -1;
case '_':
cp = lexbuf;
ep = lexbuf+sizeof lexbuf;
goto talph;
case '.':
c1 = getc();
if(yy_isdigit(c1)) {
cp = lexbuf;
ep = lexbuf+sizeof lexbuf;
*cp++ = c;
c = c1;
goto casedot;
}
if(c1 == '.') {
c1 = getc();
if(c1 == '.') {
c = LDDD;
goto lx;
}
ungetc(c1);
c1 = '.';
}
break;
case '"':
/* "..." */
strcpy(lexbuf, "\"<string>\"");
cp = mal(8);
clen = sizeof(int32);
ncp = 8;
for(;;) {
if(clen+UTFmax > ncp) {
cp = remal(cp, ncp, ncp);
ncp += ncp;
}
if(escchar('"', &escflag, &v))
break;
if(v < Runeself || escflag) {
cp[clen++] = v;
} else {
rune = v;
c = runelen(rune);
runetochar(cp+clen, &rune);
clen += c;
}
}
goto strlit;
case '`':
/* `...` */
strcpy(lexbuf, "`<string>`");
cp = mal(8);
clen = sizeof(int32);
ncp = 8;
for(;;) {
if(clen+UTFmax > ncp) {
cp = remal(cp, ncp, ncp);
ncp += ncp;
}
c = getr();
if(c == '\r')
continue;
if(c == EOF) {