Add Quoted-Printable encoding function

src/fmail.c

@@ -23,6 +23,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <getopt.h>
+#include <ctype.h>
 
 
 /* Help and informations about the program. */
@@ -60,6 +61,58 @@ See the COPYING file or <http://www.gnu.org/licenses/gpl.html>.\n\
 
 
 
+/* Helper functions. */
+
+static void
+qp_encode_stream(FILE *in, FILE *out)
+{
+    int c;
+    unsigned n;
+
+    n = 0;
+    while ( ! feof(in) ) {
+
+        c = fgetc(in);
+
+        if ( n >= 72 ) {
+            fprintf(out, "=\r\n");
+            n = 0;
+        }
+
+        if ( c == '\t' || c == ' ' ) {
+            int next = fgetc(in);
+
+            if ( next == '\n' ) {
+                fprintf(out, "=%02X", c);
+                n += 3;
+            }
+            else {
+                fputc(c, out);
+                n += 1;
+            }
+            ungetc(next, in);
+        }
+        else if ( c == '=' ) {
+            fprintf(out, "=%02X", c);
+            n += 3;
+        }
+        else if ( isprintc(c) ) {
+            fputc(c, out);
+            n += 1;
+        }
+        else if ( c == '\n' ) {
+            fprintf(out, "\r\n");
+            n = 0;
+        }
+        else if ( c != EOF ) {
+            fprintf(out, "=%02X", c);
+            n += 3;
+        }
+    }
+}
+
+
+
 /* Main function. */
 
 int