From dc08ff26ea833b68f6b5e55f24efba675b718d58 Mon Sep 17 00:00:00 2001
From: Art Cancro <ajc@citadel.org>
Date: Tue, 31 Jan 2017 22:47:57 -0500
Subject: [PATCH] New function StrBufDecodeQP() to decode a quoted-printable
 StrBuf in-place without reallocation

---
 libcitadel/configure.in     |  4 ++--
 libcitadel/lib/libcitadel.h |  5 +++--
 libcitadel/lib/stringbuf.c  | 43 ++++++++++++++++++++++++++++++++++++-
 3 files changed, 47 insertions(+), 5 deletions(-)

diff --git a/libcitadel/configure.in b/libcitadel/configure.in
index 2be9c363d..21c0636d0 100755
--- a/libcitadel/configure.in
+++ b/libcitadel/configure.in
@@ -5,7 +5,7 @@ dnl
 dnl Ensure that libcitadel is configured with autoconf 2.52 or newer
 AC_PREREQ(2.52)
 
-AC_INIT(libcitadel, 903, http://uncensored.citadel.org)
+AC_INIT(libcitadel, 904, http://uncensored.citadel.org)
 
 AC_CONFIG_SRCDIR(Makefile.in)
 AC_CONFIG_AUX_DIR(conftools)
@@ -20,7 +20,7 @@ dnl Set LIBAGE to 0.
 dnl
 
 LIBCURRENT=4
-LIBREVISION=903
+LIBREVISION=904
 LIBAGE=0
 
 sinclude(conftools/libtool.m4)
diff --git a/libcitadel/lib/libcitadel.h b/libcitadel/lib/libcitadel.h
index eb0247001..87ab9f21c 100644
--- a/libcitadel/lib/libcitadel.h
+++ b/libcitadel/lib/libcitadel.h
@@ -1,7 +1,7 @@
 /*
  * Header file for libcitadel
  *
- * Copyright (c) 1987-2016 by the citadel.org team
+ * Copyright (c) 1987-2017 by the citadel.org team
  *
  * This program is open source software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License version 3.
@@ -28,7 +28,7 @@
 #include <sys/types.h>
 #include <netinet/in.h>
 
-#define LIBCITADEL_VERSION_NUMBER	903
+#define LIBCITADEL_VERSION_NUMBER	904
 
 /*
  * Here's a bunch of stupid magic to make the MIME parser portable.
@@ -353,6 +353,7 @@ int StrBufDestroyStreamContext(eStreamType type, vStreamT **Stream, const char *
 int StrBufStreamTranscode(eStreamType type, IOBuffer *Target, IOBuffer *In, const char* pIn, long pInLen, vStreamT *Stream, int LastChunk, const char **Err);
 
 int StrBufDecodeBase64(StrBuf *Buf);
+void StrBufDecodeQP(StrBuf *Buf);
 int StrBufDecodeBase64To(const StrBuf *BufIn, StrBuf *BufOut);
 int StrBufDecodeHex(StrBuf *Buf);
 StrBuf *StrBufRFC2047encodeMessage(const StrBuf *EncodeMe);
diff --git a/libcitadel/lib/stringbuf.c b/libcitadel/lib/stringbuf.c
index 12fd259e4..8398757de 100644
--- a/libcitadel/lib/stringbuf.c
+++ b/libcitadel/lib/stringbuf.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 1987-2013 by the citadel.org team
+ * Copyright (c) 1987-2017 by the citadel.org team
  *
  * This program is open source software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -5622,3 +5622,44 @@ void StrBufStripSlashes(StrBuf *Dir, int RemoveTrailingSlash)
 }
 
 
+/*
+ * Decode a quoted-printable encoded StrBuf buffer "in place"
+ * This is possible because the decoded will always be shorter than the encoded
+ * so we don't have to worry about the buffer being to small.
+ */
+void StrBufDecodeQP(StrBuf *Buf)
+{
+	if (!Buf) {				// sanity check #1
+		return;
+	}
+
+	int source_len = StrLength(Buf);
+	if (source_len < 1) {			// sanity check #2
+		return;
+	}
+
+	int spos = 0;				// source position
+	int tpos = 0;				// target position
+
+	while (spos < source_len) {
+		if (!strncmp(&Buf->buf[spos], "=\r\n", 3)) {
+			spos += 3;
+		}
+		else if (!strncmp(&Buf->buf[spos], "=\n", 2)) {
+			spos += 2;
+		}
+		else if (Buf->buf[spos] == '=') {
+			++spos;
+			int ch;
+			sscanf(&Buf->buf[spos], "%02x", &ch);
+			Buf->buf[tpos++] = ch;
+			spos +=2;
+		}
+		else {
+			Buf->buf[tpos++] = Buf->buf[spos++];
+		}
+	}
+
+	Buf->buf[tpos] = 0;
+	Buf->BufUsed = tpos;
+}
-- 
2.30.2