Backtrace tool WORK-IN-PROGRESS

1 files changed, 95 insertions, 0 deletions

diff --git a/src/Backtrace/strbuf.c b/src/Backtrace/strbuf.c
new file mode 100644
index 0000000..8cdb482
--- /dev/null
+++ b/src/Backtrace/strbuf.c
@@ -0,0 +1,95 @@
+/*
+    strbuf.c - string buffer implementation
+
+    Copyright (C) 2009  RedHat inc.
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+    GNU General Public License for more details.
+
+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+#include "strbuf.h"
+#include <stdlib.h>
+#include <assert.h>
+#include <string.h>
+
+struct strbuf *strbuf_new()
+{
+  struct strbuf *buf = malloc(sizeof(struct strbuf));
+  if (!buf)
+  {
+    puts("Error while allocating memory for string buffer.");
+    exit(5);
+  }
+
+  buf->alloc = 8;
+  buf->len = 0;
+  buf->buf = malloc(buf->alloc);
+  if (!buf->buf)
+  {
+    puts("Error while allocating memory for string buffer.");
+    exit(5);
+  }
+  
+  buf->buf[buf->len] = '\0';
+  return buf;
+}
+
+void strbuf_free(struct strbuf *buf)
+{
+  free(buf->buf);
+  free(buf);
+}
+
+void strbuf_clear(struct strbuf *buf)
+{
+  assert(buf->alloc > 0);
+  buf->len = 0;
+  buf->buf[0] = '\0';
+}
+
+/* Ensures that the buffer can be extended by num characters
+ * without touching malloc/realloc.
+ */
+static void strbuf_grow(struct strbuf *buf, int num)
+{
+  if (buf->len + num + 1 > buf->alloc)
+  {
+    while (buf->len + num + 1 > buf->alloc)
+      buf->alloc *= 2; /* huge grow = infinite loop */
+
+    buf->buf = realloc(buf->buf, buf->alloc);
+    if (!buf->buf)
+    {
+      puts("Error while allocating memory for string buffer.");
+      exit(5);
+    }
+  }
+}
+
+struct strbuf *strbuf_append_char(struct strbuf *buf, char c)
+{
+  strbuf_grow(buf, 1);
+  buf->buf[buf->len++] = c;
+  buf->buf[buf->len] = '\0';
+  return buf;
+}
+
+struct strbuf *strbuf_append_str(struct strbuf *buf, char *str)
+{
+  int len = strlen(str);
+  strbuf_grow(buf, len);
+  assert(buf->len + len < buf->alloc);
+  strcpy(buf->buf + buf->len, str);
+  buf->len += len;
+  return buf;
+}