GUAC-236: Add stub structure for image decoding.

src/guacenc/Makefile.am

@@ -30,14 +30,17 @@ noinst_HEADERS =   \
     encode.h       \
     image-stream.h \
     instructions.h \
+    jpeg.h         \
     layer.h        \
-    log.h
+    log.h          \
+    png.h
 
 guacenc_SOURCES =          \
     buffer.c               \
     display.c              \
     encode.c               \
     guacenc.c              \
+    image-stream.c         \
     instructions.c         \
     instruction-blob.c     \
     instruction-cfill.c    \
@@ -52,8 +55,16 @@ guacenc_SOURCES =          \
     instruction-size.c     \
     instruction-sync.c     \
     instruction-transfer.c \
+    jpeg.c                 \
     layer.c                \
-    log.c
+    log.c                  \
+    png.c
+
+# Compile WebP support if available
+if ENABLE_WEBP
+guacenc_SOURCES += webp.c
+noinst_HEADERS  += webp.h
+endif
 
 guacenc_CFLAGS =            \
     -Werror -Wall -pedantic \

src/guacenc/image-stream.c

@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config.h"
+#include "image-stream.h"
+#include "jpeg.h"
+#include "png.h"
+
+#ifdef ENABLE_WEBP
+#include "webp.h"
+#endif
+
+#include <stdlib.h>
+
+guacenc_decoder_mapping guacenc_decoder_map[] = {
+    {"image/png",  &guacenc_png_decoder},
+    {"image/jpeg", &guacenc_jpeg_decoder},
+#ifdef ENABLE_WEBP
+    {"image/webp", &guacenc_webp_decoder},
+#endif
+    {NULL,         NULL}
+};
+

src/guacenc/image-stream.h

@@ -24,6 +24,13 @@
 #define GUACENC_IMAGE_STREAM_H
 
 #include "config.h"
+#include "buffer.h"
+
+/**
+ * A decoder implementation which processes arbitrary image data of a
+ * particular type. Image data is fed explicitly into the decoder as chunks.
+ */
+typedef struct guacenc_decoder guacenc_decoder;
 
 /**
  * The current state of an allocated Guacamole image stream.
@@ -41,7 +48,150 @@ typedef struct guacenc_image_stream {
      */
     int mask;
 
+    /**
+     * The X coordinate of the upper-left corner of the rectangle within the
+     * destination layer or buffer that the decoded image should be drawn to.
+     */
+    int x;
+
+    /**
+     * The Y coordinate of the upper-left corner of the rectangle within the
+     * destination layer or buffer that the decoded image should be drawn to.
+     */
+    int y;
+
+    /**
+     * The decoder to use when decoding the raw data received along this
+     * stream, or NULL if no such decoder exists.
+     */
+    guacenc_decoder* decoder;
+
+    /**
+     * Arbitrary implementation-specific data associated with the stream.
+     */
+    void* data;
+
 } guacenc_image_stream;
 
+/**
+ * Callback function which is invoked when a decoder has been assigned to an
+ * image stream.
+ *
+ * @param stream
+ *     The image stream that the decoder has been assigned to.
+ *
+ * @return
+ *     Zero if initialization was successful, non-zero otherwise.
+ */
+typedef int guacenc_decoder_init_handler(guacenc_image_stream* stream);
+
+/**
+ * Callback function which is invoked when data has been received along an
+ * image stream with an associated decoder.
+ *
+ * @param stream
+ *     The image stream that the decoder was assigned to.
+ *
+ * @param data
+ *     The chunk of data received along the image stream.
+ *
+ * @param length
+ *     The length of the chunk of data received, in bytes.
+ *
+ * @return
+ *     Zero if the provided data was processed successfully, non-zero
+ *     otherwise.
+ */
+typedef int guacenc_decoder_data_handler(guacenc_image_stream* stream,
+        unsigned char* data, int length);
+
+/**
+ * Callback function which is invoked when an image stream with an associated
+ * decoder has ended (reached end-of-stream). The image stream will contain
+ * the required meta-information describing the drawing operation, including
+ * the destination X/Y coordinates.
+ *
+ * @param stream
+ *     The image stream that has ended.
+ *
+ * @param buffer
+ *     The buffer to which the decoded image should be drawn.
+ *
+ * @return
+ *     Zero if the end of the stream has been processed successfully and the
+ *     resulting image has been rendered to the given buffer, non-zero
+ *     otherwise.
+ */
+typedef int guacenc_decoder_end_handler(guacenc_image_stream* stream,
+        guacenc_buffer* buffer);
+
+/**
+ * Callback function which will be invoked when the data associated with an
+ * image stream must be freed. This may happen at any time, and will not
+ * necessarily occur only after the image stream has ended. It is possible
+ * that an image stream will be in-progress at the end of a protocol dump, thus
+ * the memory associated with the stream will need to be freed without ever
+ * ending.
+ *
+ * @param stream
+ *     The stream whose associated data must be freed.
+ *
+ * @return
+ *     Zero if the data was successfully freed, non-zero otherwise.
+ */
+typedef int guacenc_decoder_free_handler(guacenc_image_stream* stream);
+
+struct guacenc_decoder {
+
+    /**
+     * Callback invoked when this decoder has just been assigned to an image
+     * stream.
+     */
+    guacenc_decoder_init_handler* init_handler;
+
+    /**
+     * Callback invoked when data has been received along an image stream to
+     * which this decoder has been assigned.
+     */
+    guacenc_decoder_data_handler* data_handler;
+
+    /**
+     * Callback invoked when an image stream to which this decoder has been
+     * assigned has ended (reached end-of-stream).
+     */
+    guacenc_decoder_end_handler* end_handler;
+
+    /**
+     * Callback invoked when data associated with an image stream by this
+     * decoder must be freed.
+     */
+    guacenc_decoder_free_handler* free_handler;
+
+};
+
+/**
+ * Mapping of image mimetype to corresponding decoder.
+ */
+typedef struct guacenc_decoder_mapping {
+
+    /**
+     * The mimetype of the image that the associated decoder can read.
+     */
+    const char* mimetype;
+
+    /**
+     * The decoder to use when an image stream of the associated mimetype is
+     * received.
+     */
+    guacenc_decoder* decoder;
+
+} guacenc_decoder_mapping;
+
+/**
+ * Array of all mimetype/decoder mappings for all supported image types,
+ * terminated by an entry with a NULL mimetype.
+ */
+extern guacenc_decoder_mapping guacenc_decoder_map[];
+
 #endif
 

src/guacenc/jpeg.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config.h"
+#include "buffer.h"
+#include "image-stream.h"
+#include "jpeg.h"
+
+#include <stdlib.h>
+
+int guacenc_jpeg_init(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_jpeg_data(guacenc_image_stream* stream, unsigned char* data,
+        int length) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_jpeg_end(guacenc_image_stream* stream, guacenc_buffer* buffer) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_jpeg_free(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+guacenc_decoder guacenc_jpeg_decoder = {
+    .init_handler = guacenc_jpeg_init,
+    .data_handler = guacenc_jpeg_data,
+    .end_handler  = guacenc_jpeg_end,
+    .free_handler = guacenc_jpeg_free
+};
+

src/guacenc/jpeg.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef GUACENC_JPEG_H
+#define GUACENC_JPEG_H
+
+#include "config.h"
+#include "image-stream.h"
+
+/**
+ * Decoder implementation which handles "image/jpeg" images.
+ */
+extern guacenc_decoder guacenc_jpeg_decoder;
+
+#endif
+

src/guacenc/png.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config.h"
+#include "buffer.h"
+#include "image-stream.h"
+#include "png.h"
+
+#include <stdlib.h>
+
+int guacenc_png_init(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_png_data(guacenc_image_stream* stream, unsigned char* data,
+        int length) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_png_end(guacenc_image_stream* stream, guacenc_buffer* buffer) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_png_free(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+guacenc_decoder guacenc_png_decoder = {
+    .init_handler = guacenc_png_init,
+    .data_handler = guacenc_png_data,
+    .end_handler  = guacenc_png_end,
+    .free_handler = guacenc_png_free
+};
+

src/guacenc/png.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef GUACENC_PNG_H
+#define GUACENC_PNG_H
+
+#include "config.h"
+#include "image-stream.h"
+
+/**
+ * Decoder implementation which handles "image/png" images.
+ */
+extern guacenc_decoder guacenc_png_decoder;
+
+#endif
+

src/guacenc/webp.c

@@ -0,0 +1,57 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#include "config.h"
+#include "buffer.h"
+#include "image-stream.h"
+#include "webp.h"
+
+#include <stdlib.h>
+
+int guacenc_webp_init(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_webp_data(guacenc_image_stream* stream, unsigned char* data,
+        int length) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_webp_end(guacenc_image_stream* stream, guacenc_buffer* buffer) {
+    /* STUB */
+    return 0;
+}
+
+int guacenc_webp_free(guacenc_image_stream* stream) {
+    /* STUB */
+    return 0;
+}
+
+guacenc_decoder guacenc_webp_decoder = {
+    .init_handler = guacenc_webp_init,
+    .data_handler = guacenc_webp_data,
+    .end_handler  = guacenc_webp_end,
+    .free_handler = guacenc_webp_free
+};
+

src/guacenc/webp.h

@@ -0,0 +1,35 @@
+/*
+ * Copyright (C) 2016 Glyptodon, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ * THE SOFTWARE.
+ */
+
+#ifndef GUACENC_WEBP_H
+#define GUACENC_WEBP_H
+
+#include "config.h"
+#include "image-stream.h"
+
+/**
+ * Decoder implementation which handles "image/webp" images.
+ */
+extern guacenc_decoder guacenc_webp_decoder;
+
+#endif
+