mailx/mailx-12.5-encsplit.patch

175 lines
4.1 KiB
Diff

diff --git a/mime.c b/mime.c
index 45de80a..ecac85d 100644
--- a/mime.c
+++ b/mime.c
@@ -1109,16 +1109,34 @@ fromhdr_end:
}
/*
+ * return length of this UTF-8 codepoint in bytes
+ */
+static size_t
+codepointsize(char tc)
+{
+ int rv = 0;
+ if ( ! ( tc & 0x80 ) )
+ return 1;
+ while ( tc & 0x80 )
+ {
+ rv++;
+ tc = tc<<1;
+ }
+ return rv;
+}
+
+/*
* Convert header fields to RFC 1522 format and write to the file fo.
*/
static size_t
mime_write_tohdr(struct str *in, FILE *fo)
{
char *upper, *wbeg, *wend, *charset, *lastwordend = NULL, *lastspc, b,
- *charset7;
+ *charset7, *cp;
struct str cin, cout;
- size_t sz = 0, col = 0, wr, charsetlen, charset7len;
+ size_t sz = 0, col = 0, wr, charsetlen, charset7len, cpsz;
int quoteany, mustquote, broken,
+ maxin, maxout, curin, cps,
maxcol = 65 /* there is the header field's name, too */;
upper = in->s + in->l;
@@ -1134,41 +1152,75 @@ mime_write_tohdr(struct str *in, FILE *fo)
if (mustquote_hdr(wbeg, wbeg == in->s, wbeg == &upper[-1]))
quoteany++;
}
+
+ /*
+ * rfc2047 says we cannot split multi-byte characters over
+ * encoded words, so we need to know if we're a multi-byte
+ * source stream (UTF-8 specifically) or just an 8 bit
+ * stream like ISO-8859-15
+ * so test beginning of charset since it is valid to include
+ * language in charset "UTF-8*DE" etc as per rfc 2184/2231
+ */
+ char *thisset = b&0200 ? charset : charset7;
+ int is_utf8 = ( strncasecmp( thisset, "utf-8", 5 ) == 0 );
+
if (2 * quoteany > in->l) {
/*
* Print the entire field in base64.
*/
- for (wbeg = in->s; wbeg < upper; wbeg = wend) {
+ for (wbeg = in->s; wbeg < upper; ) {
wend = upper;
cin.s = wbeg;
- for (;;) {
- cin.l = wend - wbeg;
- if (cin.l * 4/3 + 7 + charsetlen
- < maxcol - col) {
- fprintf(fo, "=?%s?B?",
- b&0200 ? charset : charset7);
- wr = mime_write_tob64(&cin, fo, 1);
- fwrite("?=", sizeof (char), 2, fo);
- wr += 7 + charsetlen;
- sz += wr, col += wr;
- if (wend < upper) {
- fwrite("\n ", sizeof (char),
- 2, fo);
- sz += 2;
- col = 0;
- maxcol = 76;
+ /*
+ * we calculate the maximum number of bytes
+ * we can use on this output line, and then what
+ * this equates to as base64 encoded source bytes
+ */
+ maxout = maxcol - col - 7 - charsetlen;
+ maxin = (maxout - (maxout & 0x03)) * 3/4;
+
+ /* short enough to finish ? */
+ if (maxin > upper - wbeg )
+ {
+ curin = upper - wbeg;
+ wbeg += curin;
+ }else
+ {
+ if (is_utf8)
+ {
+ /*
+ * now scan the input from the beginning
+ * to see how many codepoints will fit
+ */
+ curin = 0;
+ while (curin < maxin
+ && (cpsz = codepointsize(*wbeg)) <= (maxin - curin))
+ {
+ curin += cpsz;
+ wbeg += cpsz;
}
- break;
- } else {
- if (col) {
- fprintf(fo, "\n ");
- sz += 2;
- col = 0;
- maxcol = 76;
- } else
- wend -= 4;
+ }else
+ {
+ curin = maxin;
+ wbeg += maxin;
}
}
+ cin.l = curin;
+ fprintf(fo, "%s=?%s?B?", (cin.s != in->s) ? " " : "", thisset );
+ wr = mime_write_tob64(&cin, fo, 1);
+
+ if (wbeg < upper)
+ {
+ wr += fwrite("?=\n ", sizeof (char), 4, fo) * sizeof (char);
+ }else
+ {
+ wr += fwrite("?=", sizeof (char), 2, fo) * sizeof (char);
+ }
+
+ /* and shuffle pointers and counts */
+ col = 1;
+ maxcol = 76;
+ sz += wr + 7 + charsetlen + ((cin.s != in->s) ? 1 : 0 );
}
} else {
/*
@@ -1243,7 +1295,29 @@ mime_write_tohdr(struct str *in, FILE *fo)
maxcol -= wbeg -
lastspc;
} else {
- wend -= 4;
+ if (is_utf8)
+ {
+ /*
+ * make sure wend is not pointing to
+ * the middle of a codepoint
+ */
+ cp = wend;
+ while (--cp > wbeg)
+ {
+ cps = codepointsize(*cp);
+ if (cps > 1)
+ {
+ if (wend - cp - cps > 4)
+ wend -= 4;
+ else
+ wend = cp;
+ break;
+ }
+ }
+ if (cp == wbeg)
+ wend -= 4;
+ } else
+ wend -= 4;
}
free(cout.s);
}