Using cairo instead of libpng.

libguac/configure.in

@@ -44,12 +44,12 @@ AC_PROG_LIBTOOL
 
 # Checks for libraries.
 AC_CHECK_LIB([dl], [dlopen],, AC_MSG_ERROR("libdl is required for loading client plugins"))
-AC_CHECK_LIB([png], [png_write_png],, AC_MSG_ERROR("libpng is required for writing png messages"))
+AC_CHECK_LIB([cairo], [cairo_create],, AC_MSG_ERROR("cairo is required for drawing instructions"))
 AC_CHECK_LIB([pthread], [pthread_create])
 AC_CHECK_LIB([wsock32], [main])
 
 # Checks for header files.
-AC_CHECK_HEADERS([fcntl.h stdlib.h string.h sys/socket.h time.h sys/time.h syslog.h unistd.h pngstruct.h])
+AC_CHECK_HEADERS([fcntl.h stdlib.h string.h sys/socket.h time.h sys/time.h syslog.h unistd.h cairo.h])
 
 # Checks for typedefs, structures, and compiler characteristics.
 AC_TYPE_SIZE_T
@@ -58,7 +58,7 @@ AC_TYPE_SSIZE_T
 # Checks for library functions.
 AC_FUNC_MALLOC
 AC_FUNC_REALLOC
-AC_CHECK_FUNCS([clock_gettime gettimeofday memmove memset select strdup png_get_io_ptr nanosleep])
+AC_CHECK_FUNCS([clock_gettime gettimeofday memmove memset select strdup nanosleep])
 
 AC_CONFIG_FILES([Makefile])
 AC_OUTPUT

libguac/include/client.h

@@ -39,8 +39,6 @@
 #ifndef _GUAC_CLIENT_H
 #define _GUAC_CLIENT_H
 
-#include <png.h>
-
 #include "guacio.h"
 #include "protocol.h"
 
@@ -309,25 +307,6 @@ int guac_start_client(guac_client* client);
  */
 void guac_free_client(guac_client* client);
 
-/**
- * Allocate a libpng-compatible buffer to hold raw image data.
- *
- * @param w The width of the buffer to allocate, in pixels.
- * @param h The height of the buffer to allocate, in pixels.
- * @param bpp The number of bytes per pixel (3 for RGB images, 4 for RGBA).
- * @return A pointer to the newly allocated buffer.
- */
-png_byte** guac_alloc_png_buffer(int w, int h, int bpp);
-
-/**
- * Free all memory associated with the given libpng-compatible buffer
- * as allocated by guac_alloc_png_buffer.
- *
- * @param png_buffer The buffer to free.
- * @param h The height of the buffer to free.
- */
-void guac_free_png_buffer(png_byte** png_buffer, int h);
-
 /**
  * Call the appropriate handler defined by the given client for the given
  * instruction. A comparison is made between the instruction opcode and the

libguac/include/protocol.h

@@ -38,7 +38,7 @@
 #ifndef _GUAC_PROTOCOL_H
 #define _GUAC_PROTOCOL_H
 
-#include <png.h>
+#include <cairo/cairo.h>
 
 #include "guacio.h"
 
@@ -214,14 +214,10 @@ int guac_send_copy(GUACIO* io, int srcl, int srcx, int srcy, int w, int h,
  * @param layer The index of the destination layer.
  * @param x The destination X coordinate.
  * @param y The destination Y coordinate.
- * @param png_rows A libpng-compatible PNG image buffer containing the image
+ * @param surface A cairo surface containing the image data to send.
- *                 data to send.
- * @param w The width of the image in the image buffer.
- * @param h The height of the image in the image buffer.
  * @return Zero on success, non-zero on error.
  */
-int guac_send_png(GUACIO* io, int layer, int x, int y,
+int guac_send_png(GUACIO* io, int layer, int x, int y, cairo_surface_t* surface);
-        png_byte** png_rows, int w, int h);
 
 /**
  * Sends a cursor instruction over the given GUACIO connection. The PNG image
@@ -230,14 +226,10 @@ int guac_send_png(GUACIO* io, int layer, int x, int y,
  * @param io The GUACIO connection to use.
  * @param x The X coordinate of the cursor hotspot.
  * @param y The Y coordinate of the cursor hotspot.
- * @param png_rows A libpng-compatible PNG image buffer containing the image
+ * @param surface A cairo surface containing the image data to send.
- *                 data to send.
- * @param w The width of the image in the image buffer.
- * @param h The height of the image in the image buffer.
  * @return Zero on success, non-zero on error.
  */
-int guac_send_cursor(GUACIO* io, int x, int y,
+int guac_send_cursor(GUACIO* io, int x, int y, cairo_surface_t* surface);
-        png_byte** png_rows, int w, int h);
 
 /**
  * Returns whether new instruction data is available on the given GUACIO

libguac/src/client.c

@@ -47,33 +47,6 @@
 #include "client.h"
 #include "client-handlers.h"
 
-png_byte** guac_alloc_png_buffer(int w, int h, int bpp) {
-
-    png_byte** png_buffer;
-    png_byte* row;
-    int y;
-
-    /* Allocate rows for PNG */
-    png_buffer = (png_byte**) malloc(h * sizeof(png_byte*));
-    for (y=0; y<h; y++) {
-        row = (png_byte*) malloc(sizeof(png_byte) * bpp * w);
-        png_buffer[y] = row;
-    }
-
-    return png_buffer;
-}
-
-void guac_free_png_buffer(png_byte** png_buffer, int h) {
-
-    int y;
-
-    /* Free PNG data */
-    for (y = 0; y<h; y++)
-        free(png_buffer[y]);
-    free(png_buffer);
-
-}
-
 guac_client* __guac_alloc_client(GUACIO* io) {
 
     /* Allocate new client (not handoff) */

libguac/src/protocol.c

@@ -35,9 +35,11 @@
  *
  * ***** END LICENSE BLOCK ***** */
 
-#ifdef HAVE_CLOCK_GETTIME
+#if defined(HAVE_CLOCK_GETTIME) || defined(HAVE_NANOSLEEP)
 #include <time.h>
-#else
+#endif
+
+#ifndef HAVE_CLOCK_GETTIME
 #include <sys/time.h>
 #endif
 
@@ -45,11 +47,8 @@
 #include <stdio.h>
 #include <string.h>
 #include <errno.h>
-#include <png.h>
 
-#ifdef HAVE_PNGSTRUCT_H
+#include <cairo/cairo.h>
-#include <pngstruct.h>
-#endif
 
 #include <sys/types.h>
 
@@ -292,75 +291,21 @@ int guac_send_copy(GUACIO* io, int srcl, int srcx, int srcy, int w, int h, int d
 
 }
 
-void __guac_write_png(png_structp png, png_bytep data, png_size_t length) {
+cairo_status_t __guac_write_png(void* closure, const unsigned char* data, unsigned int length) {
 
-#ifdef HAVE_PNG_GET_IO_PTR
+    GUACIO* io = (GUACIO*) closure;
-    GUACIO* io = (GUACIO*) png_get_io_ptr(png);
-#else
-    /* Direct access to io_ptr has been deprecated, but we'll
-       use it if we have to. */
-    GUACIO* io = (GUACIO*) png->io_ptr;
-#endif
 
-    if (guac_write_base64(io, data, length) < 0) {
+    if (guac_write_base64(io, data, length) < 0)
-        perror("Error writing PNG");
+        return CAIRO_STATUS_WRITE_ERROR;
-        png_error(png, "Error writing PNG");
+
-        return;
+    return CAIRO_STATUS_SUCCESS;
-    }
 
 }
 
-void __guac_write_flush(png_structp png) {
+int guac_send_png(GUACIO* io, int layer, int x, int y, cairo_surface_t* surface) {
-}
 
-int guac_send_png(GUACIO* io, int layer, int x, int y, png_byte** png_rows, int w, int h) {
+    /* Write instruction and args */
 
-    png_structp png;
-    png_infop png_info;
-
-    /* Write image */
-
-    /* Set up PNG writer */
-    png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
-    if (!png) {
-        return -1;
-    }
-
-    png_info = png_create_info_struct(png);
-    if (!png_info) {
-        png_destroy_write_struct(&png, NULL);
-        return -1;
-    }
-
-#ifdef GUAC_FAST_PNG
-    /* Do not filter (speed) */
-    png_set_filter(png, PNG_FILTER_TYPE_BASE, PNG_FILTER_VALUE_NONE);
-
-    /* Fast compression level */
-    png_set_compression_level(png, 1);
-#endif
-
-    /* Set error handler */
-    if (setjmp(png_jmpbuf(png))) {
-        png_destroy_write_struct(&png, &png_info);
-        return -1;
-    }
-
-    png_set_write_fn(png, io, __guac_write_png, __guac_write_flush);
-
-    /* Set PNG IHDR */
-    png_set_IHDR(
-            png,
-            png_info,
-            w,
-            h,
-            8,
-            PNG_COLOR_TYPE_RGB,
-            PNG_INTERLACE_NONE,
-            PNG_COMPRESSION_TYPE_DEFAULT,
-            PNG_FILTER_TYPE_DEFAULT
-    );
-    
     if (
            guac_write_string(io, "png:")
         || guac_write_int(io, layer)
@@ -370,64 +315,30 @@ int guac_send_png(GUACIO* io, int layer, int x, int y, png_byte** png_rows, int
         || guac_write_int(io, y)
         || guac_write_string(io, ",")
        ) {
-        png_destroy_write_struct(&png, &png_info);
         return -1;
     }
 
-    png_set_rows(png, png_info, png_rows);
+    /* Write surface */
-    png_write_png(png, png_info, PNG_TRANSFORM_IDENTITY, NULL);
+
+    if (cairo_surface_write_to_png_stream(surface, __guac_write_png, io) != CAIRO_STATUS_SUCCESS) {
+        return -1;
+    }
 
     if (guac_flush_base64(io) < 0) {
-        png_destroy_write_struct(&png, &png_info);
         return -1;
     }
 
-    png_destroy_write_struct(&png, &png_info);
+    /* Finish instruction */
+
     return guac_write_string(io, ";");
 
 }
 
 
-int guac_send_cursor(GUACIO* io, int x, int y, png_byte** png_rows, int w, int h) {
+int guac_send_cursor(GUACIO* io, int x, int y, cairo_surface_t* surface) {
 
-    png_structp png;
+    /* Write instruction and args */
-    png_infop png_info;
 
-    /* Write image */
-
-    /* Set up PNG writer */
-    png = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
-    if (!png) {
-        return -1;
-    }
-
-    png_info = png_create_info_struct(png);
-    if (!png_info) {
-        png_destroy_write_struct(&png, NULL);
-        return -1;
-    }
-
-    /* Set error handler */
-    if (setjmp(png_jmpbuf(png))) {
-        png_destroy_write_struct(&png, &png_info);
-        return -1;
-    }
-
-    png_set_write_fn(png, io, __guac_write_png, __guac_write_flush);
-
-    /* Set PNG IHDR */
-    png_set_IHDR(
-            png,
-            png_info,
-            w,
-            h,
-            8,
-            PNG_COLOR_TYPE_RGBA,
-            PNG_INTERLACE_NONE,
-            PNG_COMPRESSION_TYPE_DEFAULT,
-            PNG_FILTER_TYPE_DEFAULT
-    );
-    
     if (
            guac_write_string(io, "cursor:")
         || guac_write_int(io, x)
@@ -435,19 +346,21 @@ int guac_send_cursor(GUACIO* io, int x, int y, png_byte** png_rows, int w, int h
         || guac_write_int(io, y)
         || guac_write_string(io, ",")
        ) {
-        png_destroy_write_struct(&png, &png_info);
         return -1;
     }
 
-    png_set_rows(png, png_info, png_rows);
+    /* Write surface */
-    png_write_png(png, png_info, PNG_TRANSFORM_IDENTITY, NULL);
+
+    if (cairo_surface_write_to_png_stream(surface, __guac_write_png, io) != CAIRO_STATUS_SUCCESS) {
+        return -1;
+    }
 
     if (guac_flush_base64(io) < 0) {
-        png_destroy_write_struct(&png, &png_info);
         return -1;
     }
 
-    png_destroy_write_struct(&png, &png_info);
+    /* Finish instruction */
+
     return guac_write_string(io, ";");
 
 }