1 files changed, 160 insertions, 0 deletions
diff --git a/rfc822/rfc822hdr.c b/rfc822/rfc822hdr.c
new file mode 100644
index 0000000..1ce3106
--- /dev/null
+++ b/rfc822/rfc822hdr.c
@@ -0,0 +1,160 @@
+/*
+** Copyright 2001-2011 Double Precision, Inc.
+** See COPYING for distribution information.
+*/
+
+#include	"config.h"
+#include	<stdio.h>
+#include	<ctype.h>
+#include	<stdlib.h>
+#include	<string.h>
+#include	"rfc822hdr.h"
+
+
+/*
+** Read the next mail header.
+*/
+
+int rfc822hdr_read(struct rfc822hdr *h, FILE *f, off_t *pos, off_t epos)
+{
+	size_t n=0;
+	int c;
+
+	for (;;)
+	{
+		if ( n >= h->hdrsize)
+		{
+			size_t hn=h->hdrsize + 1024;
+			char *p= h->header ? realloc(h->header, hn):
+				malloc(hn);
+
+			if (!p)
+				return (-1);
+
+			h->header=p;
+			h->hdrsize=hn;
+		}
+
+		if (pos && *pos >= epos)
+		{
+			h->header[n]=0;
+			break;
+		}
+
+		c=getc(f);
+		if (c == EOF)
+		{
+			if (pos)
+				*pos=epos;
+			h->header[n]=0;
+			break;
+		}
+		if (pos)
+			++*pos;
+
+		h->header[n]=c;
+		if (c == '\n')
+		{
+			if (n == 0)
+			{
+				if (pos)
+					*pos=epos;
+				h->header[n]=0;
+				break;
+			}
+
+			c=getc(f);
+			if (c != EOF)
+				ungetc(c, f);
+			if (c == '\n' || c == '\r' ||
+			    !isspace((int)(unsigned char)c))
+			{
+				h->header[n]=0;
+				break;
+			}
+		}
+		n++;
+		if (h->maxsize && n + 2 > h->maxsize)
+			--n;
+	}
+
+	if (n == 0)
+	{
+		if (pos)
+			*pos=epos;
+		h->value=h->header;
+		return (1);
+	}
+
+	for (h->value=h->header; *h->value; ++h->value)
+	{
+		if (*h->value == ':')
+		{
+			*h->value++=0;
+			while (*h->value &&
+			       isspace((int)(unsigned char)*h->value))
+				++h->value;
+			break;
+		}
+	}
+	return (0);
+}
+
+void rfc822hdr_fixname(struct rfc822hdr *h)
+{
+	char *p;
+
+	for (p=h->header; *p; p++)
+	{
+		*p=tolower((int)(unsigned char)*p);
+	}
+}
+
+void rfc822hdr_collapse(struct rfc822hdr *h)
+{
+	char *p, *q;
+
+	for (p=q=h->value; *p; )
+	{
+		if (*p == '\n')
+		{
+			while (*p && isspace((int)(unsigned char)*p))
+				++p;
+			*q++=' ';
+			continue;
+		}
+		*q++ = *p++;
+	}
+	*q=0;
+}
+
+/* This is, basically, a case-insensitive US-ASCII comparison function */
+
+#define lc(x) ((x) >= 'A' && (x) <= 'Z' ? (x) + ('a'-'A'):(x))
+
+int rfc822hdr_namecmp(const char *a, const char *b)
+{
+	int rc;
+
+	while ((rc=(int)(unsigned char)lc(*a) - (int)(unsigned char)lc(*b))==0)
+	{
+		if (!*a)
+			return 0;
+		++a;
+		++b;
+	}
+
+	return rc;
+}
+
+int rfc822hdr_is_addr(const char *hdr)
+{
+	return rfc822hdr_namecmp(hdr, "from") == 0 ||
+		rfc822hdr_namecmp(hdr, "to") == 0 ||
+		rfc822hdr_namecmp(hdr, "cc") == 0 ||
+		rfc822hdr_namecmp(hdr, "bcc") == 0 ||
+		rfc822hdr_namecmp(hdr, "resent-from") == 0 ||
+		rfc822hdr_namecmp(hdr, "resent-to") == 0 ||
+		rfc822hdr_namecmp(hdr, "resent-cc") == 0 ||
+		rfc822hdr_namecmp(hdr, "resent-bcc") == 0;
+}