package libpng: add test program

src/libpng-test.c

@@ -0,0 +1,69 @@
+/* This file is part of mingw-cross-env.       */
+/* See doc/index.html for further information. */
+
+/* This is a slightly modified version of:     */
+/* http://ironalbatross.net/wiki/index.php5?title=CPP_LIBPNG#Minimal_Example_of_writing_a_PNG_File */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <string.h>
+#include <png.h>
+ 
+int main(int argc, char *argv[])
+{
+    (void)argc;
+    (void)argv;
+    
+    /* PNG structs and types */
+    png_byte color_type;
+    png_byte bit_depth;
+    png_structp png_ptr;
+    png_infop info_ptr;
+    png_bytep *row_pointers;
+ 
+    int height, width;
+    FILE *fp;
+ 
+    width = 640;
+    height = 480;
+ 
+    color_type = PNG_COLOR_TYPE_RGB;
+    bit_depth = 8; /* Number of bits per color, not per pixel */
+ 
+    /* Dynamic 2D array in C */
+    row_pointers = (png_bytep *)malloc( sizeof(png_bytep) * height);
+    int i;
+    for(i = 0; i < height; i++)
+    {
+        int j;
+        row_pointers[i] = malloc(sizeof(png_byte) * width * 3);
+        for(j = 0; j < width; j++)
+        {
+            row_pointers[i][0+3*j] = i % 255;   /* R */
+            row_pointers[i][1+3*j] = j % 255;   /* G */
+            row_pointers[i][2+3*j] = (i * j) % 255; /* B */
+        }
+    }
+ 
+    /* Write the data out to the PNG file */
+    fp = fopen("test.png","wb");
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING,NULL,NULL,NULL);
+    info_ptr = png_create_info_struct(png_ptr);
+    png_init_io(png_ptr,fp);
+    png_set_IHDR(png_ptr, info_ptr, width, height,
+                 bit_depth, color_type, PNG_INTERLACE_NONE,
+                 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+    png_write_info(png_ptr, info_ptr);
+    png_write_image(png_ptr, row_pointers);
+    png_write_end(png_ptr, NULL);
+ 
+    /* Free up memory after use */
+    for(i = 0; i < height; i++)
+    {
+        free(row_pointers[i]);
+    }
+    free(row_pointers);
+ 
+    return 0;
+}

src/libpng.mk

@@ -30,4 +30,9 @@ define $(PKG)_BUILD
         --disable-shared \
         --prefix='$(PREFIX)/$(TARGET)'
     $(MAKE) -C '$(1)' -j '$(JOBS)' install bin_PROGRAMS= sbin_PROGRAMS= noinst_PROGRAMS=
+    
+    '$(TARGET)-gcc' \
+        -W -Wall -Werror -std=c99 -pedantic \
+        '$(2).c' -o '$(PREFIX)/$(TARGET)/bin/test-libpng.exe' \
+        `'$(PREFIX)/$(TARGET)/bin/libpng-config' --static --cflags --libs`
 endef