1 files changed, 127 insertions, 0 deletions
diff --git a/third_party/spiro/ppedit/sexp.c b/third_party/spiro/ppedit/sexp.c
new file mode 100644
index 0000000..b4f0de4
--- /dev/null
+++ b/third_party/spiro/ppedit/sexp.c
@@ -0,0 +1,127 @@
+/*
+ppedit - A pattern plate editor for Spiro splines.
+Copyright (C) 2007 Raph Levien
+
+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.
+
+You should have received a copy of the GNU General Public License
+along with this program; if not, write to the Free Software
+Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+02110-1301, USA.
+
+*/
+#include <stdio.h>
+#include <math.h>
+
+#include "sexp.h"
+
+/* This is handcoded to avoid locale problems. */
+static int
+parse_double(sexp_reader *sr)
+{
+    double sign = 1.0, val = 0.0;
+    int i;
+    int numstart;
+    const char * const b = sr->tokbuf;
+    int is_double = 1;
+
+    i = 0;
+    if (b[i] == '+') {
+	i++;
+    } else if (b[i] == '-') {
+	sign = -1.0;
+	i++;
+    }
+    numstart = i;
+    while (b[i] >= '0' && b[i] <= '9')
+	val = val * 10.0 + b[i++] - '0';
+    if (b[i] == '.') {
+	double frac = 1.0;
+
+	for (i++; b[i] >= '0' && b[i] <= '9'; i++) {
+	    frac *= 0.1;
+	    val += (b[i] - '0') * frac;
+	}
+
+	/* A '.' without any digits on either side isn't valid. */
+	if (i == numstart + 1)
+	    is_double = 0;
+    }
+    if (b[i] == 'e' || b[i] == 'E') {
+	int expsign = 1, exp = 0;
+	int expstart;
+
+	if (b[i] == '+') {
+	    i++;
+	} else if (b[i] == '-') {
+	    expsign = -1;
+	    i++;
+	}
+	expstart = i;
+	while (b[i] >= '0' && b[i] <= '9')
+	    exp = exp * 10 + b[i++] - '0';
+
+	if (i == expstart)
+	    is_double = 0;
+	val *= pow(10.0, expsign * exp);
+    }
+    val *= sign;
+    sr->d = val;
+    if (b[i] != 0) is_double = 0;
+    sr->is_double = is_double;
+    return is_double;
+}
+
+/* Return values: 0 = EOF, 1 = token but not double, 2 = valid double */
+int
+sexp_token(sexp_reader *sr)
+{
+    int c;
+    int i;
+
+    sr->singlechar = -1;
+    if (sr->f == NULL)
+	return 0;
+
+    for (;;) {
+	c = getc(sr->f);
+	if (c == EOF) {
+	    sr->f = NULL;
+	    return 0;
+	} else if (c == '#') {
+	    do {
+		c = getc(sr->f);
+	    } while (c != EOF && c != '\r' && c != '\n');
+	} else if (c != ' ' && c != '\r' && c != '\n' && c != '\t')
+	    break;
+    }
+    sr->tokbuf[0] = c;
+    i = 1;
+    if (c != '(' && c != ')') {
+	for (;;) {
+	    c = getc(sr->f);
+	    if (c == EOF) {
+		sr->f = NULL;
+		break;
+	    } else if (c == ' ' || c == '\r' || c == '\n' || c == '\t') {
+		break;
+	    } else if (c == '(' || c == ')' || c == '#') {
+		ungetc(c, sr->f);
+		break;
+	    } else if (i < sizeof(sr->tokbuf) - 1)
+		sr->tokbuf[i++] = c;
+	}
+    }
+    sr->tokbuf[i] = 0;
+    if (i == 1)
+	sr->singlechar = sr->tokbuf[0];
+    return 1 + parse_double(sr);
+}