--- /dev/null
+/*
+ * code39.c -- encoding for code39
+ *
+ * Copyright (c) 1999 Alessandro Rubini (rubini@gnu.org)
+ * Copyright (c) 1999 Prosa Srl. (prosa@prosa.it)
+ *
+ * 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <errno.h>
+
+#include "barcode.h"
+
+
+/* this is ordered in decades to simplify encoding */
+static char alphabet[] =
+ "1234567890" "ABCDEFGHIJ" "KLMNOPQRST" "UVWXYZ-. *" "$/+%";
+
+/* the checksum alphabet has a different order */
+static char checkbet[] =
+ "0123456789" "ABCDEFGHIJ" "KLMNOPQRST" "UVWXYZ-. $" "/+%";
+
+/* The first 40 symbols repeat this bar pattern */
+static char *bars[] = {
+ "31113","13113","33111","11313","31311",
+ "13311","11133","31131","13131","11331"};
+
+/* The first 4 decades use these space patterns */
+static char *spaces[] = {"1311","1131","1113","3111"};
+
+/* the last four symbols are special */
+static char *specialbars[] = {
+ "11111","11111","11111","11111"};
+
+static char *specialspaces[] = {
+ "3331","3313","3133","1333"};
+
+static char *fillers[]= {
+ "0a3a1c1c1a",
+ "1a3a1c1c1a"
+};
+
+
+/*
+ * Check that the text can be encoded. Returns 0 or -1.
+ * If it's all lowecase convert to uppercase and accept it
+ */
+int Barcode_39_verify(unsigned char *text)
+{
+ int i, lower=0, upper=0;
+
+ if (text[0] == '\0')
+ return -1;
+ for (i=0; text[i]; i++) {
+ if (isupper(text[i])) upper++;
+ if (islower(text[i])) lower++;
+ if (!strchr(alphabet,toupper(text[i])))
+ return -1;
+ }
+ if (lower && upper)
+ return -1;
+ return 0;
+}
+
+static int add_one(char *ptr, int code)
+{
+ char *b, *s;
+
+ if (code < 40) {
+ b = bars[code%10];
+ s = spaces[code/10];
+ } else {
+ b = specialbars[code-40];
+ s = specialspaces[code-40];
+ }
+ sprintf(ptr,"1%c%c%c%c%c%c%c%c%c", /* separator */
+ b[0], s[0], b[1], s[1], b[2], s[2],
+ b[3], s[3], b[4]);
+ return 0;
+}
+
+/*
+ * The encoding functions fills the "partial" and "textinfo" fields.
+ * Lowercase chars are converted to uppercase
+ */
+int Barcode_39_encode(struct Barcode_Item *bc)
+{
+ static char *text;
+ static char *partial; /* dynamic */
+ static char *textinfo; /* dynamic */
+ char *c, *ptr, *textptr;
+ int i, code, textpos, checksum = 0;
+
+ if (bc->partial)
+ free(bc->partial);
+ if (bc->textinfo)
+ free(bc->textinfo);
+ bc->partial = bc->textinfo = NULL; /* safe */
+
+ if (!bc->encoding)
+ bc->encoding = strdup("code 39");
+
+ text = bc->ascii;
+ if (!text) {
+ bc->error = EINVAL;
+ return -1;
+ }
+ /* the partial code is 10* (head + text + check + tail) + margin + term. */
+ partial = malloc( (strlen(text) + 3) * 10 +2);
+ if (!partial) {
+ bc->error = errno;
+ return -1;
+ }
+
+ /* the text information is at most "nnn:fff:c " * strlen +term */
+ textinfo = malloc(10*strlen(text) + 2);
+ if (!textinfo) {
+ bc->error = errno;
+ free(partial);
+ return -1;
+ }
+
+ strcpy(partial, fillers[0]);
+ ptr = partial + strlen(partial);
+ textptr = textinfo;
+ textpos = 22;
+
+ for (i=0; text[i]; i++) {
+ c = strchr(alphabet, toupper(text[i]));
+ if (!c) {
+ bc->error = EINVAL; /* impossible if text is verified */
+ free(partial);
+ free(textinfo);
+ return -1;
+ }
+ code = c - alphabet;
+ add_one(ptr, code);
+ c = strchr(checkbet,*c);
+ if (c) /* the '*' is not there */
+ checksum += (c-checkbet);
+ sprintf(textptr, "%i:12:%c ", textpos, toupper(text[i]));
+
+ textpos += 16; /* width of each code */
+ textptr += strlen(textptr);
+ ptr += strlen(ptr);
+ }
+ /* Add the checksum */
+ if ( (bc->flags & BARCODE_NO_CHECKSUM)==0 ) {
+ code = (strchr(alphabet, checkbet[checksum % 43]) - alphabet);
+ add_one(ptr, code);
+ }
+ strcat(ptr, fillers[1]); /* end */
+ bc->partial = partial;
+ bc->textinfo = textinfo;
+
+ return 0;
+}