X-Git-Url: https://git.lttng.org/?p=lttng-tools.git;a=blobdiff_plain;f=src%2Fcommon%2Fbuffer-view.c;h=04bd1ca354f5555b4b78063ba523684cd93b52c2;hp=4e84b0335eccee4b3a6c786f6014b07a1be4dd01;hb=df62dbcd26798ca35926f8316a1b5734e825b84b;hpb=ff28f8657b7eafa590f914e85dcd30935244cc97

diff --git a/src/common/buffer-view.c b/src/common/buffer-view.c
index 4e84b0335..04bd1ca35 100644
--- a/src/common/buffer-view.c
+++ b/src/common/buffer-view.c
@@ -1,18 +1,8 @@
 /*
- * Copyright (C) 2017 - Jérémie Galarneau <jeremie.galarneau@efficios.com>
+ * Copyright (C) 2017 Jérémie Galarneau <jeremie.galarneau@efficios.com>
  *
- * This program is free software; you can redistribute it and/or modify it
- * under the terms of the GNU Lesser General Public License, version 2.1 only,
- * as published by the Free Software Foundation.
+ * SPDX-License-Identifier: LGPL-2.1-only
  *
- * 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 Lesser General Public License
- * for more details.
- *
- * You should have received a copy of the GNU Lesser 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 <common/buffer-view.h>
@@ -20,6 +10,20 @@
 #include <common/error.h>
 #include <assert.h>
 
+LTTNG_HIDDEN
+struct lttng_buffer_view lttng_buffer_view_init(
+		const char *src, size_t offset, ptrdiff_t len)
+{
+	struct lttng_buffer_view view = { .data = src + offset, .size = len };
+	return view;
+}
+
+LTTNG_HIDDEN
+bool lttng_buffer_view_is_valid(const struct lttng_buffer_view *view)
+{
+	return view && view->data && view->size > 0;
+}
+
 LTTNG_HIDDEN
 struct lttng_buffer_view lttng_buffer_view_from_view(
 		const struct lttng_buffer_view *src, size_t offset,
@@ -30,12 +34,14 @@ struct lttng_buffer_view lttng_buffer_view_from_view(
 	assert(src);
 
 	if (offset > src->size) {
-		ERR("Attempt to create buffer view with invalid offset");
+		ERR("Attempt to create buffer view from another view with invalid offset (offset > source size): source size = %zu, offset in source = %zu, length = %zd",
+				src->size, offset, len);
 		goto end;
 	}
 
 	if (len != -1 && len > (src->size - offset)) {
-		ERR("Attempt to create buffer view with invalid length");
+		ERR("Attempt to create buffer view from another view with invalid length (length > space left after offset in source): source size = %zu, offset in source = %zu, length = %zd",
+				src->size, offset, len);
 		goto end;
 	}
 
@@ -55,12 +61,14 @@ struct lttng_buffer_view lttng_buffer_view_from_dynamic_buffer(
 	assert(src);
 
 	if (offset > src->size) {
-		ERR("Attempt to create buffer view with invalid offset");
+		ERR("Attempt to create buffer view from a dynamic buffer with invalid offset (offset > source size): source size = %zu, offset in source = %zu, length = %zd",
+				src->size, offset, len);
 		goto end;
 	}
 
 	if (len != -1 && len > (src->size - offset)) {
-		ERR("Attempt to create buffer view with invalid length");
+		ERR("Attempt to create buffer view from a dynamic buffer with invalid length (length > space left after offset in source): source size = %zu, offset in source = %zu, length = %zd",
+				src->size, offset, len);
 		goto end;
 	}
 
@@ -69,3 +77,45 @@ struct lttng_buffer_view lttng_buffer_view_from_dynamic_buffer(
 end:
 	return view;
 }
+
+LTTNG_HIDDEN
+bool lttng_buffer_view_contains_string(const struct lttng_buffer_view *buf,
+		const char *str,
+		size_t len_with_null_terminator)
+{
+	const char *past_buf_end;
+	size_t max_str_len_with_null_terminator;
+	size_t str_len;
+	bool ret;
+
+	past_buf_end = buf->data + buf->size;
+
+	/* Is the start of the string in the buffer view? */
+	if (str < buf->data || str >= past_buf_end) {
+		ret = false;
+		goto end;
+	}
+
+	/*
+	 * Max length the string could have to fit in the buffer, including
+	 * NULL terminator.
+	 */
+	max_str_len_with_null_terminator = past_buf_end - str;
+
+	/* Could the string even fit in the buffer? */
+	if (len_with_null_terminator > max_str_len_with_null_terminator) {
+		ret = false;
+		goto end;
+	}
+
+	str_len = lttng_strnlen(str, max_str_len_with_null_terminator);
+	if (str_len != (len_with_null_terminator - 1)) {
+		ret = false;
+		goto end;
+	}
+
+	ret = true;
+
+end:
+	return ret;
+}