X-Git-Url: http://git.marmaro.de/?p=mmh;a=blobdiff_plain;f=sbr%2Ffold.c;fp=sbr%2Ffold.c;h=01893827b19159eddd41ea2d14de39382036923a;hp=0000000000000000000000000000000000000000;hb=c9076497c235510f9358f9e3eadfe91fbfa9d5e3;hpb=1546f528c670a4a55d0016a754a8f062674a9efe

diff --git a/sbr/fold.c b/sbr/fold.c
new file mode 100644
index 0000000..0189382
--- /dev/null
+++ b/sbr/fold.c
@@ -0,0 +1,61 @@
+/* fold.c -- fold a mail header field
+ *
+ * This code is Copyright (c), by the authors of nmh.  See the
+ * COPYRIGHT file in the root directory of the nmh distribution for
+ * complete copyright information. */
+
+#include <h/mh.h>
+#include <stdio.h>
+
+void
+fold(charstring_t dst, size_t namelen, const char *restrict body)
+{
+	const char *restrict body_next;
+	const char *restrict wsp;
+	const char *restrict wsp_next;
+	const int crlf = strchr(body, '\r') != NULL;
+	charstring_clear(dst);
+	namelen++;
+
+	while (*body) {
+		body_next = strchr(body, '\n');
+		if ((unsigned long) (body_next - body) <= MAXTEXTPERLN - namelen) {
+			charstring_push_back_chars(dst, body, body_next - body + 1);
+			namelen = 0;
+			body = body_next + 1;
+			continue;
+		}
+		wsp = body;
+		while (namelen == 0 && (*wsp == ' ' || *wsp == '\t')) {
+			wsp++;
+		}
+		wsp = wsp_next = strpbrk(wsp, " \t");
+
+		/* if now whitespace is in the current line just print the curret line as is */
+		if (!wsp_next || wsp_next > body_next) {
+			charstring_push_back_chars(dst, body, body_next - body + 1);
+			namelen = 0;
+			body = body_next + 1;
+			continue;
+		}
+
+		while ((unsigned long)(wsp_next - body) <= MAXTEXTPERLN - namelen) {
+			wsp = wsp_next;
+			wsp_next = strpbrk(wsp+1, " \t");
+			if (!wsp_next) {
+				break;
+			}
+			if (wsp_next > body_next) {
+				break;
+			}
+		}
+
+		charstring_push_back_chars(dst, body, wsp - body);
+		if (crlf) {
+			charstring_push_back(dst, '\r');
+		}
+		charstring_push_back(dst, '\n');
+		namelen = 0;
+		body = wsp;
+	}
+}