1 files changed, 103 insertions, 0 deletions
diff --git a/assorted/pack.c b/assorted/pack.c
new file mode 100644
index 0000000..9eec65e
--- /dev/null
+++ b/assorted/pack.c
@@ -0,0 +1,103 @@
+/*
+ *	libHX/assorted/pack.c
+ *	Copyright Jan Engelhardt, 1999-2005
+ *
+ *	This file is part of libHX. libHX is free software; you can
+ *	redistribute it and/or modify it under the terms of the GNU Lesser
+ *	General Public License as published by the Free Software Foundation;
+ *	either version 2.1 or (at your option) any later version.
+ */
+#include <sys/types.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <string.h>
+
+size_t HX_pack(char *buf, size_t buflen, const char *fmt, ...)
+{
+	char *obp = buf;
+	int run = 1;
+	va_list ap;
+	va_start(ap, fmt);
+
+	while (run && *fmt != '\0') {
+		switch (*fmt++) {
+		case 'A': /* string with up to 255 chars */
+		case 'a': {
+			const char *src = va_arg(ap, const char *);
+			size_t slen = strlen(src) & 0xFF;
+			if (buflen < slen + 1) {
+				run = 0;
+				break;
+			}
+			*buf++ = slen;
+			memcpy(buf, src, slen);
+			buf    += slen;
+			buflen -= slen + 1;
+			break;
+		}
+		case 'C': /* unsigned char */
+		case 'c':
+			if (buflen-- < 1) {
+				run = 0;
+				break;
+			}
+			/*
+			 * Minimum object's size being pushed on the stack is 2
+			 * bytes since short int is promoted to int when passed
+			 * thru va_arg and stays uncasted. (FIXME)
+			 */
+			*buf++ = va_arg(ap, unsigned int);
+			break;
+		case 'H': /* unsigned short */
+		case 'h':
+			if (buflen < sizeof(uint16_t)) {
+				run = 0;
+				break;
+			}
+			*((uint16_t *)buf) = va_arg(ap, uint16_t);
+			buf    += sizeof(uint16_t);
+			buflen -= sizeof(uint16_t);
+			break;
+		case 'L': /* unsigned long */
+		case 'l':
+			if (buflen < sizeof(uint32_t)) {
+				run = 0;
+				break;
+			}
+			*((uint32_t *)buf) = va_arg(ap, uint32_t);
+			buf    += sizeof(uint32_t);
+			buflen -= sizeof(uint32_t);
+			break;
+		case 'S': /* string with up to 65535 chars */
+		case 's': {
+			const char *src = va_arg(ap, const char *);
+			size_t slen = strlen(src) & 0xFFFF;
+			if (buflen < slen + 2) {
+				run = 0;
+				break;
+			}
+			*((unsigned short *)buf) = slen;
+			memcpy(buf += 2, src, slen);
+			buf    += slen;
+			buflen -= slen + 2;
+			break;
+		}
+		case 'V': /* fixed size string */
+		case 'v': {
+			void *src = va_arg(ap, void *);
+			size_t slen = va_arg(ap, size_t);
+			if (buflen < slen) {
+				run = 0;
+				break;
+			}
+			memcpy(buf, src, slen);
+			buf    += slen;
+			buflen -= slen;
+			break;
+		}
+		} /* switch */
+	}
+
+	va_end(ap);
+	return buf - obp;
+}