Initial version of Cgraph created.

diff --git a/lib/cgraph/agxbuf.c b/lib/cgraph/agxbuf.c
new file mode 100644 (file)
index 0000000..d9bfa39
--- /dev/null
+++ b/lib/cgraph/agxbuf.c
@@ -0,0 +1,115 @@
+/* $Id$ $Revision$ */
+/* vim:set shiftwidth=4 ts=8: */
+
+/**********************************************************
+*      This software is part of the graphviz package      *
+*                http://www.graphviz.org/                 *
+*                                                         *
+*            Copyright (c) 1994-2004 AT&T Corp.           *
+*                and is licensed under the                *
+*            Common Public License, Version 1.0           *
+*                      by AT&T Corp.                      *
+*                                                         *
+*        Information and Software Systems Research        *
+*              AT&T Research, Florham Park NJ             *
+**********************************************************/
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <agxbuf.h>
+
+#define N_GNEW(n,t)     (t*)malloc((n)*sizeof(t))
+
+/* agxbinit:
+ * Assume if init is non-null, hint = sizeof(init[])
+ */
+void agxbinit(agxbuf * xb, unsigned int hint, unsigned char *init)
+{
+    if (init) {
+       xb->buf = init;
+       xb->dyna = 0;
+    } else {
+       if (hint == 0)
+           hint = BUFSIZ;
+       xb->dyna = 1;
+       xb->buf = N_GNEW(hint, unsigned char);
+    }
+    xb->eptr = xb->buf + hint;
+    xb->ptr = xb->buf;
+    *xb->ptr = '\0';
+}
+
+/* agxbmore;
+ * Expand buffer to hold at least ssz more bytes.
+ */
+int agxbmore(agxbuf * xb, unsigned int ssz)
+{
+    int cnt;                   /* current no. of characters in buffer */
+    int size;                  /* current buffer size */
+    int nsize;                 /* new buffer size */
+    unsigned char *nbuf;       /* new buffer */
+
+    size = xb->eptr - xb->buf;
+    nsize = 2 * size;
+    if (size + ssz > nsize)
+       nsize = size + ssz;
+    cnt = xb->ptr - xb->buf;
+    if (xb->dyna) {
+       nbuf = realloc(xb->buf, nsize);
+    } else {
+       nbuf = N_GNEW(nsize, unsigned char);
+       memcpy(nbuf, xb->buf, cnt);
+       xb->dyna = 1;
+    }
+    xb->buf = nbuf;
+    xb->ptr = xb->buf + cnt;
+    xb->eptr = xb->buf + nsize;
+    return 0;
+}
+
+/* agxbput_n:
+ * Append string s of length n onto xb
+ */
+int agxbput_n(agxbuf * xb, char *s, unsigned int ssz)
+{
+    if (xb->ptr + ssz > xb->eptr)
+       agxbmore(xb, ssz);
+    memcpy(xb->ptr, s, ssz);
+    xb->ptr += ssz;
+    return ssz;
+}
+
+/* agxbput:
+ * Append string s into xb
+ */
+int agxbput(agxbuf * xb, char *s)
+{
+    unsigned int ssz = strlen(s);
+
+    return agxbput_n(xb, s, ssz);
+}
+
+/* agxbfree:
+ * Free any malloced resources.
+ */
+void agxbfree(agxbuf * xb)
+{
+    if (xb->dyna)
+       free(xb->buf);
+}
+
+/* agxbpop:
+ * Removes last character added, if any.
+ */
+int agxbpop(agxbuf * xb)
+{
+    int c;
+    if (xb->ptr > xb->buf) {
+       c = *xb->ptr--;
+       return c;
+    } else
+       return -1;
+
+}