--- /dev/null
+/*
+ * Copyright © 2016 Keith Packard <keithp@keithp.com>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ */
+
+#include "ao_scheme.h"
+#include "ao_scheme_read.h"
+#include <math.h>
+#include <stdlib.h>
+
+static const uint16_t lex_classes[128] = {
+ IGNORE, /* ^@ */
+ IGNORE, /* ^A */
+ IGNORE, /* ^B */
+ IGNORE, /* ^C */
+ IGNORE, /* ^D */
+ IGNORE, /* ^E */
+ IGNORE, /* ^F */
+ IGNORE, /* ^G */
+ IGNORE, /* ^H */
+ WHITE, /* ^I */
+ WHITE, /* ^J */
+ WHITE, /* ^K */
+ WHITE, /* ^L */
+ WHITE, /* ^M */
+ IGNORE, /* ^N */
+ IGNORE, /* ^O */
+ IGNORE, /* ^P */
+ IGNORE, /* ^Q */
+ IGNORE, /* ^R */
+ IGNORE, /* ^S */
+ IGNORE, /* ^T */
+ IGNORE, /* ^U */
+ IGNORE, /* ^V */
+ IGNORE, /* ^W */
+ IGNORE, /* ^X */
+ IGNORE, /* ^Y */
+ IGNORE, /* ^Z */
+ IGNORE, /* ^[ */
+ IGNORE, /* ^\ */
+ IGNORE, /* ^] */
+ IGNORE, /* ^^ */
+ IGNORE, /* ^_ */
+ PRINTABLE|WHITE, /* */
+ PRINTABLE, /* ! */
+ PRINTABLE|STRINGC, /* " */
+ PRINTABLE|POUND, /* # */
+ PRINTABLE, /* $ */
+ PRINTABLE, /* % */
+ PRINTABLE, /* & */
+ PRINTABLE|SPECIAL, /* ' */
+ PRINTABLE|SPECIAL, /* ( */
+ PRINTABLE|SPECIAL, /* ) */
+ PRINTABLE, /* * */
+ PRINTABLE|SIGN, /* + */
+ PRINTABLE|SPECIAL, /* , */
+ PRINTABLE|SIGN, /* - */
+ PRINTABLE|DOTC|FLOATC, /* . */
+ PRINTABLE, /* / */
+ PRINTABLE|DIGIT, /* 0 */
+ PRINTABLE|DIGIT, /* 1 */
+ PRINTABLE|DIGIT, /* 2 */
+ PRINTABLE|DIGIT, /* 3 */
+ PRINTABLE|DIGIT, /* 4 */
+ PRINTABLE|DIGIT, /* 5 */
+ PRINTABLE|DIGIT, /* 6 */
+ PRINTABLE|DIGIT, /* 7 */
+ PRINTABLE|DIGIT, /* 8 */
+ PRINTABLE|DIGIT, /* 9 */
+ PRINTABLE, /* : */
+ PRINTABLE|COMMENT, /* ; */
+ PRINTABLE, /* < */
+ PRINTABLE, /* = */
+ PRINTABLE, /* > */
+ PRINTABLE, /* ? */
+ PRINTABLE, /* @ */
+ PRINTABLE, /* A */
+ PRINTABLE, /* B */
+ PRINTABLE, /* C */
+ PRINTABLE, /* D */
+ PRINTABLE|FLOATC, /* E */
+ PRINTABLE, /* F */
+ PRINTABLE, /* G */
+ PRINTABLE, /* H */
+ PRINTABLE, /* I */
+ PRINTABLE, /* J */
+ PRINTABLE, /* K */
+ PRINTABLE, /* L */
+ PRINTABLE, /* M */
+ PRINTABLE, /* N */
+ PRINTABLE, /* O */
+ PRINTABLE, /* P */
+ PRINTABLE, /* Q */
+ PRINTABLE, /* R */
+ PRINTABLE, /* S */
+ PRINTABLE, /* T */
+ PRINTABLE, /* U */
+ PRINTABLE, /* V */
+ PRINTABLE, /* W */
+ PRINTABLE, /* X */
+ PRINTABLE, /* Y */
+ PRINTABLE, /* Z */
+ PRINTABLE, /* [ */
+ PRINTABLE|BACKSLASH, /* \ */
+ PRINTABLE, /* ] */
+ PRINTABLE, /* ^ */
+ PRINTABLE, /* _ */
+ PRINTABLE|SPECIAL, /* ` */
+ PRINTABLE, /* a */
+ PRINTABLE, /* b */
+ PRINTABLE, /* c */
+ PRINTABLE, /* d */
+ PRINTABLE|FLOATC, /* e */
+ PRINTABLE, /* f */
+ PRINTABLE, /* g */
+ PRINTABLE, /* h */
+ PRINTABLE, /* i */
+ PRINTABLE, /* j */
+ PRINTABLE, /* k */
+ PRINTABLE, /* l */
+ PRINTABLE, /* m */
+ PRINTABLE, /* n */
+ PRINTABLE, /* o */
+ PRINTABLE, /* p */
+ PRINTABLE, /* q */
+ PRINTABLE, /* r */
+ PRINTABLE, /* s */
+ PRINTABLE, /* t */
+ PRINTABLE, /* u */
+ PRINTABLE, /* v */
+ PRINTABLE, /* w */
+ PRINTABLE, /* x */
+ PRINTABLE, /* y */
+ PRINTABLE, /* z */
+ PRINTABLE, /* { */
+ PRINTABLE, /* | */
+ PRINTABLE, /* } */
+ PRINTABLE, /* ~ */
+ IGNORE, /* ^? */
+};
+
+static int lex_unget_c;
+
+static inline int
+lex_get()
+{
+ int c;
+ if (lex_unget_c) {
+ c = lex_unget_c;
+ lex_unget_c = 0;
+ } else {
+ c = ao_scheme_getc();
+ }
+ return c;
+}
+
+static inline void
+lex_unget(int c)
+{
+ if (c != EOF)
+ lex_unget_c = c;
+}
+
+static uint16_t lex_class;
+
+static int
+lexc(void)
+{
+ int c;
+ do {
+ c = lex_get();
+ if (c == EOF) {
+ c = 0;
+ lex_class = ENDOFFILE;
+ } else {
+ c &= 0x7f;
+ lex_class = lex_classes[c];
+ }
+ } while (lex_class & IGNORE);
+ return c;
+}
+
+static int
+lex_quoted(void)
+{
+ int c;
+ int v;
+ int count;
+
+ c = lex_get();
+ if (c == EOF) {
+ lex_class = ENDOFFILE;
+ return 0;
+ }
+ lex_class = 0;
+ c &= 0x7f;
+ switch (c) {
+ case 'n':
+ return '\n';
+ case 'f':
+ return '\f';
+ case 'b':
+ return '\b';
+ case 'r':
+ return '\r';
+ case 'v':
+ return '\v';
+ case 't':
+ return '\t';
+ case '0':
+ case '1':
+ case '2':
+ case '3':
+ case '4':
+ case '5':
+ case '6':
+ case '7':
+ v = c - '0';
+ count = 1;
+ while (count <= 3) {
+ c = lex_get();
+ if (c == EOF)
+ return EOF;
+ c &= 0x7f;
+ if (c < '0' || '7' < c) {
+ lex_unget(c);
+ break;
+ }
+ v = (v << 3) + c - '0';
+ ++count;
+ }
+ return v;
+ default:
+ return c;
+ }
+}
+
+#define AO_SCHEME_TOKEN_MAX 32
+
+static char token_string[AO_SCHEME_TOKEN_MAX];
+static int32_t token_int;
+static int token_len;
+static float token_float;
+
+static inline void add_token(int c) {
+ if (c && token_len < AO_SCHEME_TOKEN_MAX - 1)
+ token_string[token_len++] = c;
+}
+
+static inline void del_token(void) {
+ if (token_len > 0)
+ token_len--;
+}
+
+static inline void end_token(void) {
+ token_string[token_len] = '\0';
+}
+
+struct namedfloat {
+ const char *name;
+ float value;
+};
+
+static const struct namedfloat namedfloats[] = {
+ { .name = "+inf.0", .value = INFINITY },
+ { .name = "-inf.0", .value = -INFINITY },
+ { .name = "+nan.0", .value = NAN },
+ { .name = "-nan.0", .value = NAN },
+};
+
+#define NUM_NAMED_FLOATS (sizeof namedfloats / sizeof namedfloats[0])
+
+static int
+_lex(void)
+{
+ int c;
+
+ token_len = 0;
+ for (;;) {
+ c = lexc();
+ if (lex_class & ENDOFFILE)
+ return END;
+
+ if (lex_class & WHITE)
+ continue;
+
+ if (lex_class & COMMENT) {
+ while ((c = lexc()) != '\n') {
+ if (lex_class & ENDOFFILE)
+ return END;
+ }
+ continue;
+ }
+
+ if (lex_class & (SPECIAL|DOTC)) {
+ add_token(c);
+ end_token();
+ switch (c) {
+ case '(':
+ case '[':
+ return OPEN;
+ case ')':
+ case ']':
+ return CLOSE;
+ case '\'':
+ return QUOTE;
+ case '.':
+ return DOT;
+ case '`':
+ return QUASIQUOTE;
+ case ',':
+ c = lexc();
+ if (c == '@') {
+ add_token(c);
+ end_token();
+ return UNQUOTE_SPLICING;
+ } else {
+ lex_unget(c);
+ return UNQUOTE;
+ }
+ }
+ }
+ if (lex_class & POUND) {
+ c = lexc();
+ switch (c) {
+ case 't':
+ add_token(c);
+ end_token();
+ return BOOL;
+ case 'f':
+ add_token(c);
+ end_token();
+ return BOOL;
+ case '\\':
+ for (;;) {
+ int alphabetic;
+ c = lexc();
+ alphabetic = (('a' <= c && c <= 'z') || ('A' <= c && c <= 'Z'));
+ if (token_len == 0) {
+ add_token(c);
+ if (!alphabetic)
+ break;
+ } else {
+ if (alphabetic)
+ add_token(c);
+ else {
+ lex_unget(c);
+ break;
+ }
+ }
+ }
+ end_token();
+ if (token_len == 1)
+ token_int = token_string[0];
+ else if (!strcmp(token_string, "space"))
+ token_int = ' ';
+ else if (!strcmp(token_string, "newline"))
+ token_int = '\n';
+ else if (!strcmp(token_string, "tab"))
+ token_int = '\t';
+ else if (!strcmp(token_string, "return"))
+ token_int = '\r';
+ else if (!strcmp(token_string, "formfeed"))
+ token_int = '\f';
+ else {
+ ao_scheme_error(AO_SCHEME_INVALID, "invalid character token #\\%s", token_string);
+ continue;
+ }
+ return NUM;
+ }
+ }
+ if (lex_class & STRINGC) {
+ for (;;) {
+ c = lexc();
+ if (lex_class & BACKSLASH)
+ c = lex_quoted();
+ if (lex_class & (STRINGC|ENDOFFILE)) {
+ end_token();
+ return STRING;
+ }
+ add_token(c);
+ }
+ }
+ if (lex_class & PRINTABLE) {
+ int isfloat;
+ int hasdigit;
+ int isneg;
+ int isint;
+ int epos;
+
+ isfloat = 1;
+ isint = 1;
+ hasdigit = 0;
+ token_int = 0;
+ isneg = 0;
+ epos = 0;
+ for (;;) {
+ if (!(lex_class & NUMBER)) {
+ isint = 0;
+ isfloat = 0;
+ } else {
+ if (!(lex_class & INTEGER))
+ isint = 0;
+ if (token_len != epos &&
+ (lex_class & SIGN))
+ {
+ isint = 0;
+ isfloat = 0;
+ }
+ if (c == '-')
+ isneg = 1;
+ if (c == '.' && epos != 0)
+ isfloat = 0;
+ if (c == 'e' || c == 'E') {
+ if (token_len == 0)
+ isfloat = 0;
+ else
+ epos = token_len + 1;
+ }
+ if (lex_class & DIGIT) {
+ hasdigit = 1;
+ if (isint)
+ token_int = token_int * 10 + c - '0';
+ }
+ }
+ add_token (c);
+ c = lexc ();
+ if ((lex_class & (NOTNAME)) && (c != '.' || !isfloat)) {
+ unsigned int u;
+// if (lex_class & ENDOFFILE)
+// clearerr (f);
+ lex_unget(c);
+ end_token ();
+ if (isint && hasdigit) {
+ if (isneg)
+ token_int = -token_int;
+ return NUM;
+ }
+ if (isfloat && hasdigit) {
+ token_float = strtof(token_string, NULL);
+ return FLOAT;
+ }
+ for (u = 0; u < NUM_NAMED_FLOATS; u++)
+ if (!strcmp(namedfloats[u].name, token_string)) {
+ token_float = namedfloats[u].value;
+ return FLOAT;
+ }
+ return NAME;
+ }
+ }
+ }
+ }
+}
+
+static inline int lex(void)
+{
+ int parse_token = _lex();
+ RDBGI("token %d (%s)\n", parse_token, token_string);
+ return parse_token;
+}
+
+static int parse_token;
+
+struct ao_scheme_cons *ao_scheme_read_cons;
+struct ao_scheme_cons *ao_scheme_read_cons_tail;
+struct ao_scheme_cons *ao_scheme_read_stack;
+
+#define READ_IN_QUOTE 0x01
+#define READ_SAW_DOT 0x02
+#define READ_DONE_DOT 0x04
+
+static int
+push_read_stack(int cons, int read_state)
+{
+ RDBGI("push read stack %p 0x%x\n", ao_scheme_read_cons, read_state);
+ RDBG_IN();
+ if (cons) {
+ ao_scheme_read_stack = ao_scheme_cons_cons(ao_scheme_cons_poly(ao_scheme_read_cons),
+ ao_scheme__cons(ao_scheme_int_poly(read_state),
+ ao_scheme_cons_poly(ao_scheme_read_stack)));
+ if (!ao_scheme_read_stack)
+ return 0;
+ }
+ ao_scheme_read_cons = NULL;
+ ao_scheme_read_cons_tail = NULL;
+ return 1;
+}
+
+static int
+pop_read_stack(int cons)
+{
+ int read_state = 0;
+ if (cons) {
+ ao_scheme_read_cons = ao_scheme_poly_cons(ao_scheme_read_stack->car);
+ ao_scheme_read_stack = ao_scheme_poly_cons(ao_scheme_read_stack->cdr);
+ read_state = ao_scheme_poly_int(ao_scheme_read_stack->car);
+ ao_scheme_read_stack = ao_scheme_poly_cons(ao_scheme_read_stack->cdr);
+ for (ao_scheme_read_cons_tail = ao_scheme_read_cons;
+ ao_scheme_read_cons_tail && ao_scheme_read_cons_tail->cdr;
+ ao_scheme_read_cons_tail = ao_scheme_poly_cons(ao_scheme_read_cons_tail->cdr))
+ ;
+ } else {
+ ao_scheme_read_cons = 0;
+ ao_scheme_read_cons_tail = 0;
+ ao_scheme_read_stack = 0;
+ }
+ RDBG_OUT();
+ RDBGI("pop read stack %p %d\n", ao_scheme_read_cons, read_state);
+ return read_state;
+}
+
+ao_poly
+ao_scheme_read(void)
+{
+ struct ao_scheme_atom *atom;
+ char *string;
+ int cons;
+ int read_state;
+ ao_poly v = AO_SCHEME_NIL;
+
+ cons = 0;
+ read_state = 0;
+ ao_scheme_read_cons = ao_scheme_read_cons_tail = ao_scheme_read_stack = 0;
+ for (;;) {
+ parse_token = lex();
+ while (parse_token == OPEN) {
+ if (!push_read_stack(cons, read_state))
+ return AO_SCHEME_NIL;
+ cons++;
+ read_state = 0;
+ parse_token = lex();
+ }
+
+ switch (parse_token) {
+ case END:
+ default:
+ if (cons)
+ ao_scheme_error(AO_SCHEME_EOF, "unexpected end of file");
+ return _ao_scheme_atom_eof;
+ break;
+ case NAME:
+ atom = ao_scheme_atom_intern(token_string);
+ if (atom)
+ v = ao_scheme_atom_poly(atom);
+ else
+ v = AO_SCHEME_NIL;
+ break;
+ case NUM:
+ v = ao_scheme_integer_poly(token_int);
+ break;
+ case FLOAT:
+ v = ao_scheme_float_get(token_float);
+ break;
+ case BOOL:
+ if (token_string[0] == 't')
+ v = _ao_scheme_bool_true;
+ else
+ v = _ao_scheme_bool_false;
+ break;
+ case STRING:
+ string = ao_scheme_string_copy(token_string);
+ if (string)
+ v = ao_scheme_string_poly(string);
+ else
+ v = AO_SCHEME_NIL;
+ break;
+ case QUOTE:
+ case QUASIQUOTE:
+ case UNQUOTE:
+ case UNQUOTE_SPLICING:
+ if (!push_read_stack(cons, read_state))
+ return AO_SCHEME_NIL;
+ cons++;
+ read_state = READ_IN_QUOTE;
+ switch (parse_token) {
+ case QUOTE:
+ v = _ao_scheme_atom_quote;
+ break;
+ case QUASIQUOTE:
+ v = _ao_scheme_atom_quasiquote;
+ break;
+ case UNQUOTE:
+ v = _ao_scheme_atom_unquote;
+ break;
+ case UNQUOTE_SPLICING:
+ v = _ao_scheme_atom_unquote2dsplicing;
+ break;
+ }
+ break;
+ case CLOSE:
+ if (!cons) {
+ v = AO_SCHEME_NIL;
+ break;
+ }
+ v = ao_scheme_cons_poly(ao_scheme_read_cons);
+ --cons;
+ read_state = pop_read_stack(cons);
+ break;
+ case DOT:
+ if (!cons) {
+ ao_scheme_error(AO_SCHEME_INVALID, ". outside of cons");
+ return AO_SCHEME_NIL;
+ }
+ if (!ao_scheme_read_cons) {
+ ao_scheme_error(AO_SCHEME_INVALID, ". first in cons");
+ return AO_SCHEME_NIL;
+ }
+ read_state |= READ_SAW_DOT;
+ continue;
+ }
+
+ /* loop over QUOTE ends */
+ for (;;) {
+ if (!cons)
+ return v;
+
+ if (read_state & READ_DONE_DOT) {
+ ao_scheme_error(AO_SCHEME_INVALID, ". not last in cons");
+ return AO_SCHEME_NIL;
+ }
+
+ if (read_state & READ_SAW_DOT) {
+ read_state |= READ_DONE_DOT;
+ ao_scheme_read_cons_tail->cdr = v;
+ } else {
+ struct ao_scheme_cons *read = ao_scheme_cons_cons(v, AO_SCHEME_NIL);
+ if (!read)
+ return AO_SCHEME_NIL;
+
+ if (ao_scheme_read_cons_tail)
+ ao_scheme_read_cons_tail->cdr = ao_scheme_cons_poly(read);
+ else
+ ao_scheme_read_cons = read;
+ ao_scheme_read_cons_tail = read;
+ }
+
+ if (!(read_state & READ_IN_QUOTE) || !ao_scheme_read_cons->cdr)
+ break;
+
+ v = ao_scheme_cons_poly(ao_scheme_read_cons);
+ --cons;
+ read_state = pop_read_stack(cons);
+ }
+ }
+ return v;
+}
projects / fw / altos / blobdiff