ref: c093439fad6423c9545d73d5cc9fb6b7c2b9dd2d
dir: /print.c/
#ifdef PLAN9
#define snprintf snprint
int iswprint(u32int c);
#endif
#include "ieee754.h"
extern void *memrchr(const void *s, int c, size_t n);
static htable_t printconses;
static u_int32_t printlabel;
static int print_pretty;
static int print_princ;
static fixnum_t print_length;
static fixnum_t print_level;
static fixnum_t P_LEVEL;
static int SCR_WIDTH = 80;
static int HPOS=0, VPOS;
static void outc(char c, ios_t *f)
{
ios_putc(c, f);
if (c == '\n')
HPOS = 0;
else
HPOS++;
}
static void outs(char *s, ios_t *f)
{
ios_puts(s, f);
HPOS += u8_strwidth(s);
}
static void outsn(char *s, ios_t *f, size_t n)
{
ios_write(f, s, n);
HPOS += u8_strwidth(s);
}
static int outindent(int n, ios_t *f)
{
// move back to left margin if we get too indented
if (n > SCR_WIDTH-12)
n = 2;
int n0 = n;
ios_putc('\n', f);
VPOS++;
HPOS = n;
while (n >= 8) {
ios_putc('\t', f);
n -= 8;
}
while (n) {
ios_putc(' ', f);
n--;
}
return n0;
}
void fl_print_chr(char c, ios_t *f)
{
outc(c, f);
}
void fl_print_str(char *s, ios_t *f)
{
outs(s, f);
}
void print_traverse(value_t v)
{
value_t *bp;
while (iscons(v)) {
if (ismarked(v)) {
bp = (value_t*)ptrhash_bp(&printconses, (void*)v);
if (*bp == (value_t)HT_NOTFOUND)
*bp = fixnum(printlabel++);
return;
}
mark_cons(v);
print_traverse(car_(v));
v = cdr_(v);
}
if (!ismanaged(v) || issymbol(v))
return;
if (ismarked(v)) {
bp = (value_t*)ptrhash_bp(&printconses, (void*)v);
if (*bp == (value_t)HT_NOTFOUND)
*bp = fixnum(printlabel++);
return;
}
if (isvector(v)) {
if (vector_size(v) > 0)
mark_cons(v);
unsigned int i;
for(i=0; i < vector_size(v); i++)
print_traverse(vector_elt(v,i));
}
else if (iscprim(v)) {
// don't consider shared references to e.g. chars
}
else if (isclosure(v)) {
mark_cons(v);
function_t *f = (function_t*)ptr(v);
print_traverse(f->bcode);
print_traverse(f->vals);
print_traverse(f->env);
}
else if (iscvalue(v)) {
cvalue_t *cv = (cvalue_t*)ptr(v);
// don't consider shared references to ""
if (!cv_isstr(cv) || cv_len(cv)!=0)
mark_cons(v);
fltype_t *t = cv_class(cv);
if (t->vtable != NULL && t->vtable->print_traverse != NULL)
t->vtable->print_traverse(v);
}
}
static void print_symbol_name(ios_t *f, char *name)
{
int i, escape=0, charescape=0;
if ((name[0] == '\0') ||
(name[0] == '.' && name[1] == '\0') ||
(name[0] == '#') ||
isnumtok(name, NULL))
escape = 1;
i=0;
while (name[i]) {
if (!symchar(name[i])) {
escape = 1;
if (name[i]=='|' || name[i]=='\\') {
charescape = 1;
break;
}
}
i++;
}
if (escape) {
if (charescape) {
outc('|', f);
i=0;
while (name[i]) {
if (name[i]=='|' || name[i]=='\\')
outc('\\', f);
outc(name[i], f);
i++;
}
outc('|', f);
}
else {
outc('|', f);
outs(name, f);
outc('|', f);
}
}
else {
outs(name, f);
}
}
/*
The following implements a simple pretty-printing algorithm. This is
an unlimited-width approach that doesn't require an extra pass.
It uses some heuristics to guess whether an expression is "small",
and avoids wrapping symbols across lines. The result is high
performance and nice output for typical code. Quality is poor for
pathological or deeply-nested expressions, but those are difficult
to print anyway.
*/
#define SMALL_STR_LEN 20
static inline int tinyp(value_t v)
{
if (issymbol(v))
return (u8_strwidth(symbol_name(v)) < SMALL_STR_LEN);
if (fl_isstring(v))
return (cv_len((cvalue_t*)ptr(v)) < SMALL_STR_LEN);
return (isfixnum(v) || isbuiltin(v) || v==FL_F || v==FL_T || v==FL_NIL ||
v == FL_EOF || iscprim(v));
}
static int smallp(value_t v)
{
if (tinyp(v)) return 1;
if (fl_isnumber(v)) return 1;
if (iscons(v)) {
if (tinyp(car_(v)) && (tinyp(cdr_(v)) ||
(iscons(cdr_(v)) && tinyp(car_(cdr_(v))) &&
cdr_(cdr_(v))==NIL)))
return 1;
return 0;
}
if (isvector(v)) {
size_t s = vector_size(v);
return (s == 0 || (tinyp(vector_elt(v,0)) &&
(s == 1 || (s == 2 &&
tinyp(vector_elt(v,1))))));
}
return 0;
}
static int specialindent(value_t head)
{
// indent these forms 2 spaces, not lined up with the first argument
if (head == LAMBDA || head == TRYCATCH || head == definesym ||
head == defmacrosym || head == forsym)
return 2;
return -1;
}
static int lengthestimate(value_t v)
{
// get the width of an expression if we can do so cheaply
if (issymbol(v))
return u8_strwidth(symbol_name(v));
if (iscprim(v) && cp_class((cprim_t*)ptr(v)) == wchartype)
return 4;
return -1;
}
static int allsmallp(value_t v)
{
int n = 1;
while (iscons(v)) {
if (!smallp(car_(v)))
return 0;
v = cdr_(v);
n++;
if (n > 25)
return n;
}
return n;
}
static int indentafter3(value_t head, value_t v)
{
// for certain X always indent (X a b c) after b
return ((head == forsym) && !allsmallp(cdr_(v)));
}
static int indentafter2(value_t head, value_t v)
{
// for certain X always indent (X a b) after a
return ((head == definesym || head == defmacrosym) &&
!allsmallp(cdr_(v)));
}
static int indentevery(value_t v)
{
// indent before every subform of a special form, unless every
// subform is "small"
value_t c = car_(v);
if (c == LAMBDA || c == setqsym)
return 0;
if (c == IF) // TODO: others
return !allsmallp(cdr_(v));
return 0;
}
static int blockindent(value_t v)
{
// in this case we switch to block indent mode, where the head
// is no longer considered special:
// (a b c d e
// f g h i j)
return (allsmallp(v) > 9);
}
static void print_pair(ios_t *f, value_t v)
{
value_t cd;
char *op;
if (iscons(cdr_(v)) && cdr_(cdr_(v)) == NIL &&
!ptrhash_has(&printconses, (void*)cdr_(v)) &&
(((car_(v) == QUOTE) && (op = "'")) ||
((car_(v) == BACKQUOTE) && (op = "`")) ||
((car_(v) == COMMA) && (op = ",")) ||
((car_(v) == COMMAAT) && (op = ",@")) ||
((car_(v) == COMMADOT) && (op = ",.")))) {
// special prefix syntax
unmark_cons(v);
unmark_cons(cdr_(v));
outs(op, f);
fl_print_child(f, car_(cdr_(v)));
return;
}
int startpos = HPOS;
outc('(', f);
int newindent=HPOS, blk=blockindent(v);
int lastv, n=0, si, ind, est, always=0, nextsmall, thistiny;
if (!blk) always = indentevery(v);
value_t head = car_(v);
int after3 = indentafter3(head, v);
int after2 = indentafter2(head, v);
int n_unindented = 1;
while (1) {
cd = cdr_(v);
if (print_length >= 0 && n >= print_length && cd!=NIL) {
outsn("...)", f, 4);
break;
}
lastv = VPOS;
unmark_cons(v);
fl_print_child(f, car_(v));
if (!iscons(cd) || ptrhash_has(&printconses, (void*)cd)) {
if (cd != NIL) {
outsn(" . ", f, 3);
fl_print_child(f, cd);
}
outc(')', f);
break;
}
if (!print_pretty ||
((head == LAMBDA) && n == 0)) {
// never break line before lambda-list
ind = 0;
}
else {
est = lengthestimate(car_(cd));
nextsmall = smallp(car_(cd));
thistiny = tinyp(car_(v));
ind = (((VPOS > lastv) ||
(HPOS>SCR_WIDTH/2 && !nextsmall && !thistiny && n>0)) ||
(HPOS > SCR_WIDTH-4) ||
(est!=-1 && (HPOS+est > SCR_WIDTH-2)) ||
((head == LAMBDA) && !nextsmall) ||
(n > 0 && always) ||
(n == 2 && after3) ||
(n == 1 && after2) ||
(n_unindented >= 3 && !nextsmall) ||
(n == 0 && !smallp(head)));
}
if (ind) {
newindent = outindent(newindent, f);
n_unindented = 1;
}
else {
n_unindented++;
outc(' ', f);
if (n==0) {
// set indent level after printing head
si = specialindent(head);
if (si != -1)
newindent = startpos + si;
else if (!blk)
newindent = HPOS;
}
}
n++;
v = cd;
}
}
static void cvalue_print(ios_t *f, value_t v);
static int print_circle_prefix(ios_t *f, value_t v)
{
value_t label;
if ((label=(value_t)ptrhash_get(&printconses, (void*)v)) !=
(value_t)HT_NOTFOUND) {
if (!ismarked(v)) {
HPOS+=ios_printf(f, "#%ld#", numval(label));
return 1;
}
HPOS+=ios_printf(f, "#%ld=", numval(label));
}
if (ismanaged(v))
unmark_cons(v);
return 0;
}
void fl_print_child(ios_t *f, value_t v)
{
char *name;
if (print_level >= 0 && P_LEVEL >= print_level &&
(iscons(v) || isvector(v) || isclosure(v))) {
outc('#', f);
return;
}
P_LEVEL++;
switch (tag(v)) {
case TAG_NUM :
case TAG_NUM1: HPOS+=ios_printf(f, "%lld", (int64_t)numval(v)); break;
case TAG_SYM:
name = symbol_name(v);
if (print_princ)
outs(name, f);
else if (ismanaged(v)) {
outsn("#:", f, 2);
outs(name, f);
}
else
print_symbol_name(f, name);
break;
case TAG_FUNCTION:
if (v == FL_T) {
outsn("#t", f, 2);
}
else if (v == FL_F) {
outsn("#f", f, 2);
}
else if (v == FL_NIL) {
outsn("()", f, 2);
}
else if (v == FL_EOF) {
outsn("#<eof>", f, 6);
}
else if (isbuiltin(v)) {
if (!print_princ)
outsn("#.", f, 2);
outs(builtin_names[uintval(v)], f);
}
else {
assert(isclosure(v));
if (!print_princ) {
if (print_circle_prefix(f, v)) break;
function_t *fn = (function_t*)ptr(v);
outs("#fn(", f);
char *data = cvalue_data(fn->bcode);
size_t i, sz = cvalue_len(fn->bcode);
for(i=0; i < sz; i++) data[i] += 48;
fl_print_child(f, fn->bcode);
for(i=0; i < sz; i++) data[i] -= 48;
outc(' ', f);
fl_print_child(f, fn->vals);
if (fn->env != NIL) {
outc(' ', f);
fl_print_child(f, fn->env);
}
if (fn->name != LAMBDA) {
outc(' ', f);
fl_print_child(f, fn->name);
}
outc(')', f);
}
else {
outs("#<function>", f);
}
}
break;
case TAG_CPRIM:
if (v == UNBOUND)
outs("#<undefined>", f);
else
cvalue_print(f, v);
break;
case TAG_CVALUE:
case TAG_VECTOR:
case TAG_CONS:
if (!print_princ && print_circle_prefix(f, v)) break;
if (isvector(v)) {
outc('[', f);
int newindent = HPOS, est;
int i, sz = vector_size(v);
for(i=0; i < sz; i++) {
if (print_length >= 0 && i >= print_length && i < sz-1) {
outsn("...", f, 3);
break;
}
fl_print_child(f, vector_elt(v,i));
if (i < sz-1) {
if (!print_pretty) {
outc(' ', f);
}
else {
est = lengthestimate(vector_elt(v,i+1));
if (HPOS > SCR_WIDTH-4 ||
(est!=-1 && (HPOS+est > SCR_WIDTH-2)) ||
(HPOS > SCR_WIDTH/2 &&
!smallp(vector_elt(v,i+1)) &&
!tinyp(vector_elt(v,i))))
newindent = outindent(newindent, f);
else
outc(' ', f);
}
}
}
outc(']', f);
break;
}
if (iscvalue(v))
cvalue_print(f, v);
else
print_pair(f, v);
break;
}
P_LEVEL--;
}
static void print_string(ios_t *f, char *str, size_t sz)
{
char buf[512];
size_t i = 0;
uint8_t c;
static char hexdig[] = "0123456789abcdef";
outc('"', f);
if (!u8_isvalid(str, sz)) {
// alternate print algorithm that preserves data if it's not UTF-8
for(i=0; i < sz; i++) {
c = str[i];
if (c == '\\')
outsn("\\\\", f, 2);
else if (c == '"')
outsn("\\\"", f, 2);
else if (c >= 32 && c < 0x7f)
outc(c, f);
else {
outsn("\\x", f, 2);
outc(hexdig[c>>4], f);
outc(hexdig[c&0xf], f);
}
}
}
else {
while (i < sz) {
size_t n = u8_escape(buf, sizeof(buf), str, &i, sz, 1, 0);
outsn(buf, f, n-1);
}
}
outc('"', f);
}
int double_exponent(double d)
{
union ieee754_double dl;
dl.d = d;
return dl.ieee.exponent - IEEE754_DOUBLE_BIAS;
}
void snprint_real(char *s, size_t cnt, double r,
int width, // printf field width, or 0
int dec, // # decimal digits desired, recommend 16
// # of zeros in .00...0x before using scientific notation
// recommend 3-4 or so
int max_digs_rt,
// # of digits left of decimal before scientific notation
// recommend 10
int max_digs_lf)
{
int mag;
double fpart, temp;
char format[8];
char num_format[3];
int sz, keepz=0;
s[0] = '\0';
if (width == -1) {
width = 0;
keepz=1;
}
if (isnan(r)) {
if (sign_bit(r))
strncpy(s, "-nan", cnt);
else
strncpy(s, "nan", cnt);
return;
}
if (r == 0) {
strncpy(s, "0", cnt);
return;
}
num_format[0] = 'l';
num_format[2] = '\0';
mag = double_exponent(r);
mag = (int)(((double)mag)/LOG2_10 + 0.5);
if (r == 0)
mag = 0;
if ((mag > max_digs_lf-1) || (mag < -max_digs_rt)) {
num_format[1] = 'e';
temp = r/pow(10, mag); /* see if number will have a decimal */
fpart = temp - floor(temp); /* when written in scientific notation */
}
else {
num_format[1] = 'f';
fpart = r - floor(r);
}
if (fpart == 0)
dec = 0;
if (width == 0) {
snprintf(format, 8, "%%.%d%s", dec, num_format);
}
else {
snprintf(format, 8, "%%%d.%d%s", width, dec, num_format);
}
sz = snprintf(s, cnt, format, r);
/* trim trailing zeros from fractions. not when using scientific
notation, since we might have e.g. 1.2000e+100. also not when we
need a specific output width */
if (width == 0 && !keepz) {
if (sz > 2 && fpart && num_format[1]!='e') {
while (s[sz-1] == '0') {
s[sz-1]='\0';
sz--;
}
// don't need trailing .
if (s[sz-1] == '.') {
s[--sz] = '\0';
}
}
}
// TODO. currently 1.1e20 prints as 1.1000000000000000e+20; be able to
// get rid of all those zeros.
}
static numerictype_t sym_to_numtype(value_t type);
// 'weak' means we don't need to accurately reproduce the type, so
// for example #int32(0) can be printed as just 0. this is used
// printing in a context where a type is already implied, e.g. inside
// an array.
static void cvalue_printdata(ios_t *f, void *data, size_t len, value_t type,
int weak)
{
if (type == bytesym) {
unsigned char ch = *(unsigned char*)data;
if (print_princ)
outc(ch, f);
else if (weak)
HPOS+=ios_printf(f, "0x%hhx", ch);
else
HPOS+=ios_printf(f, "#byte(0x%hhx)", ch);
}
else if (type == wcharsym) {
uint32_t wc = *(uint32_t*)data;
char seq[8];
size_t nb = u8_toutf8(seq, sizeof(seq), &wc, 1);
seq[nb] = '\0';
if (print_princ) {
// TODO: better multibyte handling
if (wc == 0)
ios_putc(0, f);
else
outs(seq, f);
}
else {
outsn("#\\", f, 2);
if (wc == 0x00) outsn("nul", f, 3);
else if (wc == 0x07) outsn("alarm", f, 5);
else if (wc == 0x08) outsn("backspace", f, 9);
else if (wc == 0x09) outsn("tab", f, 3);
else if (wc == 'l') outsn("linefeed", f, 8);
else if (wc == 0x0A) outsn("newline", f, 7);
else if (wc == 0x0B) outsn("vtab", f, 4);
else if (wc == 0x0C) outsn("page", f, 4);
else if (wc == 0x0D) outsn("return", f, 6);
else if (wc == 0x1B) outsn("esc", f, 3);
else if (wc == 's') outsn("space", f, 5);
else if (wc == 0x7F) outsn("delete", f, 6);
else if (iswprint(wc)) outs(seq, f);
else HPOS+=ios_printf(f, "x%04x", (int)wc);
}
}
else if (type == floatsym || type == doublesym) {
char buf[64];
double d;
int ndec;
if (type == floatsym) { d = (double)*(float*)data; ndec = 8; }
else { d = *(double*)data; ndec = 16; }
if (!DFINITE(d)) {
char *rep;
if (isnan(d))
rep = sign_bit(d) ? "-nan.0" : "+nan.0";
else
rep = sign_bit(d) ? "-inf.0" : "+inf.0";
if (type == floatsym && !print_princ && !weak)
HPOS+=ios_printf(f, "#%s(%s)", symbol_name(type), rep);
else
outs(rep, f);
}
else if (d == 0) {
if (1/d < 0)
outsn("-0.0", f, 4);
else
outsn("0.0", f, 3);
if (type == floatsym && !print_princ && !weak)
outc('f', f);
}
else {
snprint_real(buf, sizeof(buf), d, 0, ndec, 3, 10);
int hasdec = (strpbrk(buf, ".eE") != NULL);
outs(buf, f);
if (!hasdec) outsn(".0", f, 2);
if (type == floatsym && !print_princ && !weak)
outc('f', f);
}
}
else if (type == uint64sym
#if defined(ULONG64)
|| type == ulongsym
#endif
) {
uint64_t ui64 = *(uint64_t*)data;
if (weak || print_princ)
HPOS += ios_printf(f, "%llud", ui64);
else
HPOS += ios_printf(f, "#%s(%llud)", symbol_name(type), ui64);
}
else if (issymbol(type)) {
// handle other integer prims. we know it's smaller than uint64
// at this point, so int64 is big enough to capture everything.
numerictype_t nt = sym_to_numtype(type);
if (nt == N_NUMTYPES) {
HPOS += ios_printf(f, "#<%s>", symbol_name(type));
}
else {
int64_t i64 = conv_to_int64(data, nt);
if (weak || print_princ)
HPOS += ios_printf(f, "%lld", i64);
else
HPOS += ios_printf(f, "#%s(%lld)", symbol_name(type), i64);
}
}
else if (iscons(type)) {
if (car_(type) == arraysym) {
value_t eltype = car(cdr_(type));
size_t cnt, elsize;
if (iscons(cdr_(cdr_(type)))) {
cnt = toulong(car_(cdr_(cdr_(type))), "length");
elsize = cnt ? len/cnt : 0;
}
else {
// incomplete array type
int junk;
elsize = ctype_sizeof(eltype, &junk);
cnt = elsize ? len/elsize : 0;
}
if (eltype == bytesym) {
if (print_princ) {
ios_write(f, data, len);
/*
char *nl = memrchr(data, '\n', len);
if (nl)
HPOS = u8_strwidth(nl+1);
else
HPOS += u8_strwidth(data);
*/
}
else {
print_string(f, (char*)data, len);
}
return;
}
else if (eltype == wcharsym) {
// TODO wchar
}
else {
}
size_t i;
if (!weak) {
if (eltype == uint8sym) {
outsn("#vu8(", f, 5);
}
else {
outsn("#array(", f, 7);
fl_print_child(f, eltype);
if (cnt > 0)
outc(' ', f);
}
}
else {
outc('[', f);
}
for(i=0; i < cnt; i++) {
if (i > 0)
outc(' ', f);
cvalue_printdata(f, data, elsize, eltype, 1);
data = (char*)data + elsize;
}
if (!weak)
outc(')', f);
else
outc(']', f);
}
else if (car_(type) == enumsym) {
int n = *(int*)data;
value_t syms = car(cdr_(type));
assert(isvector(syms));
if (!weak) {
outsn("#enum(", f, 6);
fl_print_child(f, syms);
outc(' ', f);
}
if (n >= (int)vector_size(syms)) {
cvalue_printdata(f, data, len, int32sym, 1);
}
else {
fl_print_child(f, vector_elt(syms, n));
}
if (!weak)
outc(')', f);
}
}
}
static void cvalue_print(ios_t *f, value_t v)
{
cvalue_t *cv = (cvalue_t*)ptr(v);
void *data = cptr(v);
value_t label;
if (cv_class(cv) == builtintype) {
void *fptr = *(void**)data;
label = (value_t)ptrhash_get(&reverse_dlsym_lookup_table, cv);
if (label == (value_t)HT_NOTFOUND) {
HPOS += ios_printf(f, "#<builtin @%p>", fptr);
}
else {
if (print_princ) {
outs(symbol_name(label), f);
}
else {
outsn("#fn(", f, 4);
outs(symbol_name(label), f);
outc(')', f);
}
}
}
else if (cv_class(cv)->vtable != NULL &&
cv_class(cv)->vtable->print != NULL) {
cv_class(cv)->vtable->print(v, f);
}
else {
value_t type = cv_type(cv);
size_t len = iscprim(v) ? cv_class(cv)->size : cv_len(cv);
cvalue_printdata(f, data, len, type, 0);
}
}
static void set_print_width(void)
{
value_t pw = symbol_value(printwidthsym);
if (!isfixnum(pw)) return;
SCR_WIDTH = numval(pw);
}
void fl_print(ios_t *f, value_t v)
{
print_pretty = (symbol_value(printprettysym) != FL_F);
if (print_pretty)
set_print_width();
print_princ = (symbol_value(printreadablysym) == FL_F);
value_t pl = symbol_value(printlengthsym);
if (isfixnum(pl)) print_length = numval(pl);
else print_length = -1;
pl = symbol_value(printlevelsym);
if (isfixnum(pl)) print_level = numval(pl);
else print_level = -1;
P_LEVEL = 0;
printlabel = 0;
if (!print_princ) print_traverse(v);
HPOS = VPOS = 0;
fl_print_child(f, v);
if (print_level >= 0 || print_length >= 0) {
memset(consflags, 0, 4*bitvector_nwords(heapsize/sizeof(cons_t)));
}
if ((iscons(v) || isvector(v) || isfunction(v) || iscvalue(v)) &&
!fl_isstring(v) && v!=FL_T && v!=FL_F && v!=FL_NIL) {
htable_reset(&printconses, 32);
}
}