am: fix patch format detection for Thunderbird "Save As" emails

diff --git a/base85.c b/base85.c
index b417a15bbc83fff7180078a4cf9f73603477a295..e459feebbf90c6557dbf3ff913f83a57a8afb210 100644 (file)
--- a/base85.c
+++ b/base85.c
@@ -57,14 +57,8 @@ int decode_85(char *dst, const char *buffer, int len)
                de = de85[ch];
                if (--de < 0)
                        return error("invalid base85 alphabet %c", ch);
-               /*
-                * Detect overflow.  The largest
-                * 5-letter possible is "|NsC0" to
-                * encode 0xffffffff, and "|NsC" gives
-                * 0x03030303 at this point (i.e.
-                * 0xffffffff = 0x03030303 * 85).
-                */
-               if (0x03030303 < acc ||
+               /* Detect overflow. */
+               if (0xffffffff / 85 < acc ||
                    0xffffffff - de < (acc *= 85))
                        return error("invalid base85 sequence %.5s", buffer-5);
                acc += de;
@@ -84,8 +78,6 @@ int decode_85(char *dst, const char *buffer, int len)
 
 void encode_85(char *buf, const unsigned char *data, int bytes)
 {
-       prep_base85();
-
        say("encode 85");
        while (bytes) {
                unsigned acc = 0;
@@ -118,7 +110,7 @@ int main(int ac, char **av)
                int len = strlen(av[2]);
                encode_85(buf, av[2], len);
                if (len <= 26) len = len + 'A' - 1;
-               else len = len + 'a' - 26 + 1;
+               else len = len + 'a' - 26 - 1;
                printf("encoded: %c%s\n", len, buf);
                return 0;
        }