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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [GTK] Avoid strstr() when checking (E)GL extensions"
href="https://bugs.webkit.org/show_bug.cgi?id=161958">161958</a>
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<th>Summary</th>
<td>[GTK] Avoid strstr() when checking (E)GL extensions
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<th>Classification</th>
<td>Unclassified
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<th>Product</th>
<td>WebKit
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<th>Version</th>
<td>WebKit Local Build
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<th>Hardware</th>
<td>Unspecified
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<th>OS</th>
<td>Unspecified
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>Normal
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<th>Priority</th>
<td>P2
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<th>Component</th>
<td>WebKit Gtk
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<th>Assignee</th>
<td>webkit-unassigned@lists.webkit.org
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<th>Reporter</th>
<td>emanuele.aina@collabora.com
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<th>CC</th>
<td>bugs-noreply@webkitgtk.org
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<p>
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<pre>Using strstr() is not sufficient to safely check for (E)GL extensions, because it may match a substring of the extension name you're testing for. For example, if you're testing for the GL_EXT_texture extension and glGetString(GL_EXTENSIONS) returns "GL_EXT_texture3D" then simply using strstr() will incorrectly tell you that GL_EXT_texture is supported. (From <a href="http://www.mesa3d.org/brianp/sig97/exten.htm">http://www.mesa3d.org/brianp/sig97/exten.htm</a> )
We currently use strstr() with no extra checks in GLContextEGL::createSurfacelessContext() (for EGL_KHR_surfaceless_context and EGL_KHR_surfaceless_opengl) and in WaylandCompositor::initializeEGL() (for EGL_KHR_image_base).
GLPlatformContext::supportsEGLExtension() does it correctly, but it seems to belong to a separate tree of GL context types (GLPlatformContext, GLXOffscreenContext and EGLOffscreenContext) which is are not used by the GTK+ port (which uses GLContext, GLContextGLX and GLContextEGL, usually by way of GraphicsContext3D).</pre>
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