1 files changed, 165 insertions, 0 deletions

diff --git a/other/ssharp/buffer.c b/other/ssharp/buffer.c
new file mode 100644
index 0000000..044caaf
--- /dev/null
+++ b/other/ssharp/buffer.c
@@ -0,0 +1,165 @@
+/*
+ * Author: Tatu Ylonen <ylo@cs.hut.fi>
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ *                    All rights reserved
+ * Functions for manipulating fifo buffers (that can grow if needed).
+ *
+ * As far as I am concerned, the code I have written for this software
+ * can be used freely for any purpose.  Any derived versions of this
+ * software must be clearly marked as such, and if the derived work is
+ * incompatible with the protocol description in the RFC file, it must be
+ * called by a name other than "ssh" or "Secure Shell".
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: buffer.c,v 1.13 2001/04/12 19:15:24 markus Exp $");
+
+#include "xmalloc.h"
+#include "buffer.h"
+#include "log.h"
+
+/* Initializes the buffer structure. */
+
+void
+buffer_init(Buffer *buffer)
+{
+        buffer->alloc = 4096;
+        buffer->buf = xmalloc(buffer->alloc);
+        buffer->offset = 0;
+        buffer->end = 0;
+}
+
+/* Frees any memory used for the buffer. */
+
+void
+buffer_free(Buffer *buffer)
+{
+        memset(buffer->buf, 0, buffer->alloc);
+        xfree(buffer->buf);
+}
+
+/*
+ * Clears any data from the buffer, making it empty.  This does not actually
+ * zero the memory.
+ */
+
+void
+buffer_clear(Buffer *buffer)
+{
+        buffer->offset = 0;
+        buffer->end = 0;
+}
+
+/* Appends data to the buffer, expanding it if necessary. */
+
+void
+buffer_append(Buffer *buffer, const char *data, u_int len)
+{
+        char *cp;
+        buffer_append_space(buffer, &cp, len);
+        memcpy(cp, data, len);
+}
+
+/*
+ * Appends space to the buffer, expanding the buffer if necessary. This does
+ * not actually copy the data into the buffer, but instead returns a pointer
+ * to the allocated region.
+ */
+
+void
+buffer_append_space(Buffer *buffer, char **datap, u_int len)
+{
+        /* If the buffer is empty, start using it from the beginning. */
+        if (buffer->offset == buffer->end) {
+                buffer->offset = 0;
+                buffer->end = 0;
+        }
+restart:
+        /* If there is enough space to store all data, store it now. */
+        if (buffer->end + len < buffer->alloc) {
+                *datap = buffer->buf + buffer->end;
+                buffer->end += len;
+                return;
+        }
+        /*
+         * If the buffer is quite empty, but all data is at the end, move the
+         * data to the beginning and retry.
+         */
+        if (buffer->offset > buffer->alloc / 2) {
+                memmove(buffer->buf, buffer->buf + buffer->offset,
+                        buffer->end - buffer->offset);
+                buffer->end -= buffer->offset;
+                buffer->offset = 0;
+                goto restart;
+        }
+        /* Increase the size of the buffer and retry. */
+        buffer->alloc += len + 32768;
+        buffer->buf = xrealloc(buffer->buf, buffer->alloc);
+        goto restart;
+}
+
+/* Returns the number of bytes of data in the buffer. */
+
+u_int
+buffer_len(Buffer *buffer)
+{
+        return buffer->end - buffer->offset;
+}
+
+/* Gets data from the beginning of the buffer. */
+
+void
+buffer_get(Buffer *buffer, char *buf, u_int len)
+{
+        if (len > buffer->end - buffer->offset)
+                fatal("buffer_get: trying to get more bytes %d than in buffer %d",
+                    len, buffer->end - buffer->offset);
+        memcpy(buf, buffer->buf + buffer->offset, len);
+        buffer->offset += len;
+}
+
+/* Consumes the given number of bytes from the beginning of the buffer. */
+
+void
+buffer_consume(Buffer *buffer, u_int bytes)
+{
+        if (bytes > buffer->end - buffer->offset)
+                fatal("buffer_consume: trying to get more bytes than in buffer");
+        buffer->offset += bytes;
+}
+
+/* Consumes the given number of bytes from the end of the buffer. */
+
+void
+buffer_consume_end(Buffer *buffer, u_int bytes)
+{
+        if (bytes > buffer->end - buffer->offset)
+                fatal("buffer_consume_end: trying to get more bytes than in buffer");
+        buffer->end -= bytes;
+}
+
+/* Returns a pointer to the first used byte in the buffer. */
+
+char *
+buffer_ptr(Buffer *buffer)
+{
+        return buffer->buf + buffer->offset;
+}
+
+/* Dumps the contents of the buffer to stderr. */
+
+void
+buffer_dump(Buffer *buffer)
+{
+        int i;
+        u_char *ucp = (u_char *) buffer->buf;
+
+        for (i = buffer->offset; i < buffer->end; i++) {
+                fprintf(stderr, "%02x", ucp[i]);
+                if ((i-buffer->offset)%16==15)
+                        fprintf(stderr, "\r\n");
+                else if ((i-buffer->offset)%2==1)
+                        fprintf(stderr, " ");
+        }
+        fprintf(stderr, "\r\n");
+}