X-Git-Url: https://code.citadel.org/?a=blobdiff_plain;f=citadel%2Ftools.c;h=0a87ebd5f0f61e9fdfed6adfa35c758412725d04;hb=be52a0c1ccd622a23fdb37076251b3df1bb99ae0;hp=0b7e1aaf720ffa6d7d4dea6161e5d72d25f22163;hpb=629b54b830c1cc3dac3c136f9b398c3fe2c1fe3e;p=citadel.git

diff --git a/citadel/tools.c b/citadel/tools.c
index 0b7e1aaf7..0a87ebd5f 100644
--- a/citadel/tools.c
+++ b/citadel/tools.c
@@ -8,6 +8,13 @@
 #include <string.h>
 #include "tools.h"
 
+#define TRUE  1
+#define FALSE 0
+
+typedef unsigned char byte;	      /* Byte type */
+static byte dtable[256];	      /* base64 encode / decode table */
+
+
 char *safestrncpy(char *dest, const char *src, size_t n)
 {
   if (dest == NULL || src == NULL)
@@ -83,3 +90,127 @@ long extract_long(char *source, long int parmnum)
 	extract_token(buf, source, parmnum, '|');
 	return(atol(buf));
 }
+
+
+
+/*
+ * decode_base64() and encode_base64() are adaptations of code by
+ * John Walker, found in full in the file "base64.c" included with this
+ * distribution.  The difference between those functions and these is that
+ * these are intended to encode/decode small string buffers, and those are
+ * intended to encode/decode entire MIME parts.
+ */
+
+void encode_base64(char *dest, char *source)
+{
+    int i, hiteof = FALSE;
+    int spos = 0;
+    int dpos = 0;
+
+    /*	Fill dtable with character encodings.  */
+
+    for (i = 0; i < 26; i++) {
+        dtable[i] = 'A' + i;
+        dtable[26 + i] = 'a' + i;
+    }
+    for (i = 0; i < 10; i++) {
+        dtable[52 + i] = '0' + i;
+    }
+    dtable[62] = '+';
+    dtable[63] = '/';
+
+    while (!hiteof) {
+	byte igroup[3], ogroup[4];
+	int c, n;
+
+	igroup[0] = igroup[1] = igroup[2] = 0;
+	for (n = 0; n < 3; n++) {
+	    c = source[spos++];
+	    if (c == 0) {
+		hiteof = TRUE;
+		break;
+	    }
+	    igroup[n] = (byte) c;
+	}
+	if (n > 0) {
+	    ogroup[0] = dtable[igroup[0] >> 2];
+	    ogroup[1] = dtable[((igroup[0] & 3) << 4) | (igroup[1] >> 4)];
+	    ogroup[2] = dtable[((igroup[1] & 0xF) << 2) | (igroup[2] >> 6)];
+	    ogroup[3] = dtable[igroup[2] & 0x3F];
+
+            /* Replace characters in output stream with "=" pad
+	       characters if fewer than three characters were
+	       read from the end of the input stream. */
+
+	    if (n < 3) {
+                ogroup[3] = '=';
+		if (n < 2) {
+                    ogroup[2] = '=';
+		}
+	    }
+	    for (i = 0; i < 4; i++) {
+		dest[dpos++] = ogroup[i];
+		dest[dpos] = 0;
+	    }
+	}
+    }
+}
+
+
+
+void decode_base64(char *dest, char *source)
+{
+    int i;
+    int dpos = 0;
+    int spos = 0;
+
+    for (i = 0; i < 255; i++) {
+	dtable[i] = 0x80;
+    }
+    for (i = 'A'; i <= 'Z'; i++) {
+        dtable[i] = 0 + (i - 'A');
+    }
+    for (i = 'a'; i <= 'z'; i++) {
+        dtable[i] = 26 + (i - 'a');
+    }
+    for (i = '0'; i <= '9'; i++) {
+        dtable[i] = 52 + (i - '0');
+    }
+    dtable['+'] = 62;
+    dtable['/'] = 63;
+    dtable['='] = 0;
+
+    /*CONSTANTCONDITION*/
+    while (TRUE) {
+	byte a[4], b[4], o[3];
+
+	for (i = 0; i < 4; i++) {
+	    int c = source[spos++];
+
+	    if (c == 0) {
+		if (i > 0) {
+		    return;
+		}
+		return;
+	    }
+	    if (dtable[c] & 0x80) {
+		/* Ignoring errors: discard invalid character. */
+		i--;
+		continue;
+	    }
+	    a[i] = (byte) c;
+	    b[i] = (byte) dtable[c];
+	}
+	o[0] = (b[0] << 2) | (b[1] >> 4);
+	o[1] = (b[1] << 4) | (b[2] >> 2);
+	o[2] = (b[2] << 6) | b[3];
+        i = a[2] == '=' ? 1 : (a[3] == '=' ? 2 : 3);
+	if (i>=1) dest[dpos++] = o[0];
+	if (i>=2) dest[dpos++] = o[1];
+	if (i>=3) dest[dpos++] = o[2];
+	dest[dpos] = 0;
+	if (i < 3) {
+	    return;
+	}
+    }
+}