Use arc4random if available

.gitignore

@@ -8,6 +8,7 @@ cmake_install.cmake
 config.h
 install_manifest.txt
 mazemaker
+*.dylib
 *.tar.gz
 *.png
 *.pc

CMakeLists.txt

@@ -1,6 +1,6 @@
 cmake_minimum_required (VERSION 3.0)
 cmake_policy(VERSION 3.0)
-project (mazemaker VERSION 1.1)
+project (mazemaker VERSION 1.5)
 
 SET(EXEC_INSTALL_PREFIX ${CMAKE_INSTALL_PREFIX} CACHE PATH "Installation prefix for executables and object code libraries" FORCE)
 SET(INCLUDE_INSTALL_DIR ${CMAKE_INSTALL_PREFIX}/include CACHE PATH "Installation prefix for C header files" FORCE)
@@ -8,6 +8,8 @@ SET(LIB_INSTALL_DIR ${CMAKE_INSTALL_PREFIX}/lib CACHE PATH  "Installation prefix
 
 CONFIGURE_FILE(${CMAKE_CURRENT_SOURCE_DIR}/mazemaker.pc.cmake ${CMAKE_CURRENT_BINARY_DIR}/mazemaker.pc)
 
+link_directories(BEFORE ${CMAKE_CURRENT_SOURCE_DIR}/lib)
+
 add_subdirectory(lib)
 add_subdirectory(utils)
 

include/mazemaker.h

@@ -22,8 +22,18 @@ typedef enum {
     EDGE_LEFT
 } mazeedge_dir_t;
 
+typedef struct mazeoptions mazeoptions_t;
+
 void mazemaker_generate_maze(int width, int height, mazegrid_t* result);
 void mazemaker_free_maze(mazegrid_t* maze);
 int mazemaker_maze_to_png(mazegrid_t const* maze, char const* filename);
+int mazemaker_maze_to_png_opt(mazegrid_t const* maze, char const* filename, mazeoptions_t const*);
+int mazemaker_maze_to_png_mem(mazegrid_t const* maze, size_t* len, uint8_t** buf);
+int mazemaker_maze_to_png_mem_opt(mazegrid_t const* maze, size_t* len, uint8_t** buf, mazeoptions_t const*);
+
+mazeoptions_t* mazemaker_options_new();
+void mazemaker_options_free(mazeoptions_t*);
+int mazemaker_options_set_wall_color(mazeoptions_t*, char const* color_desc);
+int mazemaker_options_set_background_color(mazeoptions_t*, char const* color_desc);
 
 #endif // !def(_MAZEMAKER_H)

lib/CMakeLists.txt

@@ -1,7 +1,10 @@
 project(mazemaker_lib)
 cmake_minimum_required (VERSION 2.8.12)
+
+include(CheckSymbolExists)
+
 set (mazemaker_SOVERSION_CURRENT    0)
-set (mazemaker_SOVERSION_REVISION   1)
+set (mazemaker_SOVERSION_REVISION   2)
 set (mazemaker_SOVERSION_AGE        0)
 math (EXPR mazemaker_SOVERSION_MAJOR "${mazemaker_SOVERSION_CURRENT} - ${mazemaker_SOVERSION_AGE}")
 math (EXPR mazemaker_SOVERSION_MINOR "${mazemaker_SOVERSION_AGE} + ${mazemaker_SOVERSION_REVISION}")
@@ -11,6 +14,11 @@ set (mazemaker_SOVERSION ${mazemaker_SOVERSION_MAJOR}.${mazemaker_SOVERSION_MINO
 find_package(PkgConfig REQUIRED)
 pkg_search_module(PNG REQUIRED libpng)
 
+check_symbol_exists(arc4random_uniform "stdlib.h" HAVE_ARC4RANDOM)
+
+configure_file ("${CMAKE_CURRENT_SOURCE_DIR}/config.h.in"
+                "${CMAKE_CURRENT_SOURCE_DIR}/config.h" )
+
 file(GLOB SOURCES *.c *.h)
 
 add_library(mazemaker_shared SHARED ${SOURCES})
@@ -27,9 +35,7 @@ set_target_properties(mazemaker_static PROPERTIES
 )
 install (TARGETS mazemaker_shared mazemaker_static DESTINATION ${LIB_INSTALL_DIR})
 install (FILES ${CMAKE_CURRENT_SOURCE_DIR}/../include/mazemaker.h DESTINATION ${INCLUDE_INSTALL_DIR})
-target_link_libraries(mazemaker_shared PUBLIC ${PNG_LIBRARIES} m)
-target_include_directories(mazemaker_shared PUBLIC ${PNG_INCLUDE_DIRS} ../include)
-target_include_directories(mazemaker_static PUBLIC ${PNG_INCLUDE_DIRS} ../include)
-target_compile_options(mazemaker_shared PUBLIC ${PNG_CFLAGS_OTHER})
-target_compile_options(mazemaker_static PUBLIC ${PNG_CFLAGS_OTHER})
-target_link_options(mazemaker_shared PUBLIC -L${PNG_LIBDIR})
+target_link_libraries(mazemaker_shared PUBLIC ${PNG_LIBRARIES};m)
+target_link_directories(mazemaker_shared PUBLIC ${PNG_LIBRARY_DIRS})
+target_include_directories(mazemaker_shared PUBLIC ${PNG_INCLUDE_DIRS};../include)
+target_include_directories(mazemaker_static PUBLIC ${PNG_INCLUDE_DIRS};../include)

lib/config.h.in

@@ -0,0 +1 @@
+#cmakedefine HAVE_ARC4RANDOM "@HAVE_ARC4RANDOM@"

lib/grid.c

@@ -1,5 +1,6 @@
 #include <stdlib.h>
 #include "grid.h"
+#include "config.h"
 
 #define MAX_EDGE_WEIGHT 100
 #define TOP_LEFT_CORNER "\xe2\x94\x8f"
@@ -18,6 +19,14 @@
 #define HORIZONTAL_HALF_LEFT "\xe2\x95\xb8"
 #define HORIZONTAL_HALF_RIGHT "\xe2\x95\xba"
 
+static edgeweight_t random_edgeweight() {
+#ifdef HAVE_ARC4RANDOM
+    return arc4random_uniform(MAX_EDGE_WEIGHT);
+#else // HAVE_ARC4RANDOM
+    return random()%MAX_EDGE_WEIGHT;
+#endif // HAVE_ARC4RANDOM
+}
+
 mazegrid_t mazegrid_new(size_t width, size_t height) {
     mazeedges_t** grid = calloc(height, sizeof(mazeedges_t*));
     for (size_t i = 0; i < height; i++) {
@@ -66,8 +75,8 @@ edgeweight_t mazegrid_get_edge(mazegrid_t const* g, size_t x, size_t y, mazeedge
 void mazegrid_randomize(mazegrid_t* g) {
     for (size_t i = 0; i < g->height; i++) {
         for (size_t j = 0; j < g->width; j++) {
-            if (i < g->height - 1) g->grid[i][j].up = (edgeweight_t)(random()%MAX_EDGE_WEIGHT);
-            if (j < g->width - 1) g->grid[i][j].right = (edgeweight_t)(random()%MAX_EDGE_WEIGHT);
+            if (i < g->height - 1) g->grid[i][j].up = random_edgeweight();
+            if (j < g->width - 1) g->grid[i][j].right = random_edgeweight();
         }
     }
 }

lib/image.c

@@ -6,6 +6,7 @@
 #include <string.h>
 #include <mazemaker.h>
 #include "grid.h"
+#include "options.h"
 
 #define LINE_THICKNESS 3
 #define BLOCK_SIZE 32
@@ -16,6 +17,11 @@ typedef struct {
     int w, h;
 } img_data_t;
 
+struct mem_encode {
+    uint8_t *buffer;
+    size_t size;
+};
+
 static void setPixel(img_data_t* img, int x, int y, char v) {
     //fprintf(stderr, "setPixel(img, %d, %d, %d)\n", x, y, v);
     assert((x < img->w) && (y < img->h));
@@ -38,7 +44,7 @@ static img_data_t* gridToImageData(mazegrid_t const* g) {
     result->data = malloc(result->w * result->h);
     //fprintf(stderr, "Box dimensions: %d x %d\n", result->w, result->h);
 
-    // white background
+    // set background
     memset(result->data, 0, result->w * result->h);
 
     // draw basic outline
@@ -66,16 +72,20 @@ static img_data_t* gridToImageData(mazegrid_t const* g) {
     return result;
 }
 
-static void writeImageData(img_data_t const* img, png_structp png_ptr) {
+static void writeImageData(img_data_t const* img, png_structp png_ptr, mazeoptions_t const* options) {
     for (int i = 0; i < img->h; i++) {
         png_byte row[3 * img->w];
         for (int j = 0; j < img->w; j++) {
             if (img->data[i * img->w + j]) {
-                // black
-                row[3 * j] = row[3 * j + 1] = row[3 * j + 2] = 0;
+                // wall color
+                row[3 * j] = options->wall_color[0];
+                row[3 * j + 1] = options->wall_color[1];
+                row[3 * j + 2] = options->wall_color[2];
             } else {
-                // white
-                row[3 * j] = row[3 * j + 1] = row[3 * j + 2] = 255;
+                // background
+                row[3 * j] = options->background_color[0];
+                row[3 * j + 1] = options->background_color[1];
+                row[3 * j + 2] = options->background_color[2];
             }
         }
         png_write_row(png_ptr, row);
@@ -87,7 +97,7 @@ static void freeImageData(img_data_t* img) {
     free(img);
 }
 
-int mazemaker_maze_to_png(mazegrid_t const* g, char const* filename) {
+int mazemaker_maze_to_png_opt(mazegrid_t const* g, char const* filename, mazeoptions_t const* options) {
     int code = 1;
     img_data_t* img = gridToImageData(g);
     FILE *f = NULL;
@@ -134,7 +144,7 @@ int mazemaker_maze_to_png(mazegrid_t const* g, char const* filename) {
 
     png_write_info(png_ptr, info_ptr);
 
-    writeImageData(img, png_ptr);
+    writeImageData(img, png_ptr, options);
 
     png_write_end(png_ptr, NULL);
 
@@ -150,3 +160,90 @@ exit:
     if (img != NULL) freeImageData(img);
     return code;
 }
+
+int mazemaker_maze_to_png(mazegrid_t const* g, char const* filename) {
+    mazeoptions_t* options = mazemaker_options_new(); // use default options
+    int result = mazemaker_maze_to_png_opt(g, filename, options);
+    mazemaker_options_free(options);
+    return result;
+}
+
+static void append_png_data(png_structp png_ptr, png_bytep data, png_size_t length) {
+    struct mem_encode* p = (struct mem_encode*)png_get_io_ptr(png_ptr);
+    size_t nsize = p->size + length;
+    if (p->buffer) 
+        p->buffer = realloc(p->buffer, nsize);
+    else
+        p->buffer = malloc(nsize);
+    if (!p->buffer)
+        png_error(png_ptr, "Write error");
+    memcpy(p->buffer + p->size, data, length);
+    p->size += length;
+}
+
+static void png_no_flush(png_structp png_ptr) {
+    /* noop */
+}
+
+int mazemaker_maze_to_png_mem_opt(mazegrid_t const* g, size_t* len, uint8_t** buf, mazeoptions_t const* options) {
+    int code = 1;
+    img_data_t* img = gridToImageData(g);
+    png_structp png_ptr = NULL;
+    png_infop info_ptr  = NULL;
+    struct mem_encode menc = { .buffer = NULL, .size = 0 };
+    
+    png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    if (png_ptr == NULL) {
+        fprintf(stderr, "Could not allocate PNG write struct.\n");
+        code = 0;
+        goto exit;
+    }
+
+    info_ptr = png_create_info_struct(png_ptr);
+    if (info_ptr == NULL) {
+        fprintf(stderr, "Could not allocate PNG info struct.\n");
+        code = 0;
+        goto exit;
+    }
+
+    if (setjmp(png_jmpbuf(png_ptr))) {
+        fprintf(stderr, "Error during PNG creation.\n");
+        code = 0;
+        goto exit;
+    }
+
+    png_set_write_fn(png_ptr, &menc, append_png_data, png_no_flush);
+
+    // Write header (8 bit color depth)
+    png_set_IHDR(png_ptr, info_ptr, img->w, img->h,
+                 8, PNG_COLOR_TYPE_RGB, PNG_INTERLACE_NONE,
+                 PNG_COMPRESSION_TYPE_BASE, PNG_FILTER_TYPE_BASE);
+
+    png_write_info(png_ptr, info_ptr);
+
+    writeImageData(img, png_ptr, options);
+
+    png_write_end(png_ptr, NULL);
+
+    *len = menc.size;
+    *buf = menc.buffer;
+
+exit:
+    if (!code && menc.buffer) {
+        free(menc.buffer);
+    }
+	if (info_ptr != NULL) {
+        png_free_data(png_ptr, info_ptr, PNG_FREE_ALL, -1);
+        png_destroy_info_struct(png_ptr, &info_ptr);
+    }
+    if (png_ptr != NULL) png_destroy_write_struct(&png_ptr, (png_infopp)NULL);
+    if (img != NULL) freeImageData(img);
+    return code;
+}
+
+int mazemaker_maze_to_png_mem(mazegrid_t const* g, size_t* len, uint8_t** buf) {
+    mazeoptions_t* options = mazemaker_options_new(); // use default options
+    int result = mazemaker_maze_to_png_mem_opt(g, len, buf, options);
+    mazemaker_options_free(options);
+    return result;
+}

lib/options.c

@@ -0,0 +1,80 @@
+#include <ctype.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "options.h"
+
+mazeoptions_t* mazemaker_options_new() {
+    mazeoptions_t* result = malloc(sizeof(mazeoptions_t));
+
+    // set defaults
+    memset(result->wall_color, 0, 3);
+    memset(result->background_color, 0xff, 3);
+
+    return result;
+}
+
+void mazemaker_options_free(mazeoptions_t* options) {
+    free(options);
+}
+
+static int interpretColorName(char const* color_desc, rgb_color_t dst) {
+    if (0 == strcasecmp(color_desc, "black")) { dst[0] = dst[1] = dst[2] = 0; }
+    else if (0 == strcasecmp(color_desc, "white")) { dst[0] = dst[1] = dst[2] = 0xff; }
+    else if (0 == strcasecmp(color_desc, "red")) { dst[0] = 0xff; dst[1] = dst[2] = 0; }
+    else if (0 == strcasecmp(color_desc, "blue")) { dst[0] = dst[1] = 0; dst[2] = 0xff; }
+    else if (0 == strcasecmp(color_desc, "green")) { dst[0] = dst[2] = 0; dst[1] = 0xff; }
+    else if (0 == strcasecmp(color_desc, "yellow")) { dst[2] = 0; dst[0] = dst[1] = 0xff; }
+    else if ((0 == strcasecmp(color_desc, "magenta")) ||
+             (0 == strcasecmp(color_desc, "purple"))) { dst[1] = 0; dst[0] = dst[2] = 0xff; }
+    else if (0 == strcasecmp(color_desc, "cyan")) { dst[0] = 0; dst[1] = dst[2] = 0xff; }
+    else if (0 == strcasecmp(color_desc, "orange")) { dst[0] = 0xff; dst[1] = 0x7f; dst[2] = 0; }
+    else if (0 == strcasecmp(color_desc, "brown")) { dst[0] = 0x7f; dst[1] = 0x3f; dst[2] = 0; }
+    else if ((0 == strcasecmp(color_desc, "gray")) ||
+             (0 == strcasecmp(color_desc, "grey"))) { dst[0] = dst[1] = dst[2] = 0x7f; }
+    else if (0 == strcasecmp(color_desc, "darkblue")) { dst[0] = dst[1] = 0; dst[2] = 0x7f; }
+    else if (0 == strcasecmp(color_desc, "darkgreen")) { dst[0] = dst[2] = 0; dst[1] = 0x7f; }
+    else if (0 == strcasecmp(color_desc, "darkred")) { dst[0] = 0x7f; dst[1] = dst[2] = 0; }
+    else if (0 == strcasecmp(color_desc, "pink")) { dst[0] = 0xff; dst[1] = 0xa0; dst[2] = 0xbf; }
+    else if ((0 == strcasecmp(color_desc, "darkmagenta")) ||
+             (0 == strcasecmp(color_desc, "darkpurple"))) { dst[1] = 0; dst[0] = dst[2] = 0x7f; }
+    else if (0 == strcasecmp(color_desc, "darkcyan")) { dst[0] = 0; dst[1] = dst[2] = 0x7f; }
+    else return -1;
+    return 0;
+}
+
+static int stringToColor(char const* color_desc, rgb_color_t dst) {
+    if (color_desc[0] != '#') return interpretColorName(color_desc, dst); 
+
+    size_t l;
+    for (l = 1; color_desc[l] != '\0'; l++) if (!isxdigit(color_desc[l])) return -1; // bad format
+
+    if ((l != 4) && (l != 7)) return -1; // bad format
+
+    char x2[3] = { 0, 0, 0 };
+    if (l == 4) {
+        x2[0] = x2[1] = color_desc[1];
+        sscanf(x2, "%hhx", &dst[0]);
+        x2[0] = x2[1] = color_desc[2];
+        sscanf(x2, "%hhx", &dst[1]);
+        x2[0] = x2[1] = color_desc[3];
+        sscanf(x2, "%hhx", &dst[2]);
+    } else {
+        strncpy(x2, color_desc + 1, 2);
+        sscanf(x2, "%hhx", &dst[0]);
+        strncpy(x2, color_desc + 3, 2);
+        sscanf(x2, "%hhx", &dst[1]);
+        strncpy(x2, color_desc + 5, 2);
+        sscanf(x2, "%hhx", &dst[2]);
+    }
+    return 0;
+}
+
+int mazemaker_options_set_wall_color(mazeoptions_t* options, char const* color_desc) {
+    return stringToColor(color_desc, options->wall_color);
+}
+
+int mazemaker_options_set_background_color(mazeoptions_t* options, char const* color_desc) {
+    return stringToColor(color_desc, options->background_color);
+}
+

lib/options.h

@@ -0,0 +1,13 @@
+#ifndef _OPTIONS_H
+#define _OPTIONS_H 1
+
+#include <stdint.h>
+
+typedef uint8_t rgb_color_t[3];
+
+typedef struct mazeoptions {
+    rgb_color_t wall_color;
+    rgb_color_t background_color;
+} mazeoptions_t;
+
+#endif // !def(_OPTIONS_H)

utils/CMakeLists.txt

@@ -1,11 +1,10 @@
 find_package(PkgConfig REQUIRED)
 pkg_search_module(POPT REQUIRED popt)
 
-add_executable(mazemaker)
-target_sources(mazemaker PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}/mazemaker.c)
-target_link_libraries(mazemaker PRIVATE mazemaker_shared PUBLIC ${POPT_LIBRARIES})
-target_include_directories(mazemaker PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/../include PUBLIC ${POPT_INCLUDE_DIRS})
-target_compile_options(mazemaker PUBLIC ${POPT_CFLAGS_OTHER})
-target_link_options(mazemaker PUBLIC -L${POPT_LIBDIR})
+include_directories("../include" ${POPT_INCLUDE_DIRS})
+
+add_executable(mazemaker mazemaker.c)
+target_link_directories(mazemaker PUBLIC ${POPT_LIBRARY_DIRS})
+target_link_libraries(mazemaker mazemaker_shared ${POPT_LIBRARIES})
 
 install (TARGETS mazemaker DESTINATION bin)

utils/mazemaker.c

@@ -6,12 +6,16 @@
 int main(int argc, char* argv[]) {
     char c;
     int width = 0, height = 0;
-    char const *filename = NULL;
+    char const *filename = NULL, *fg_color = NULL, *bg_color = NULL;
     struct poptOption options_table[] = {
         { "width", 'w', POPT_ARG_INT, &width, 0,
           "Width of the maze", "BLOCKS" },
         { "height", 'h', POPT_ARG_INT, &height, 0,
           "Height of the maze", "BLOCKS" },
+        { "foreground", 'f', POPT_ARG_STRING, &fg_color, 0,
+          "Foreground (wall) color", "#rrggbb" },
+        { "background", 'b', POPT_ARG_STRING, &bg_color, 0,
+          "Background color", "#rrggbb" },
         POPT_AUTOHELP
         { NULL, 0, 0, NULL, 0 }
     };
@@ -36,8 +40,22 @@ int main(int argc, char* argv[]) {
         return 1;
     }
     mazegrid_t maze;
+    mazeoptions_t* options = mazemaker_options_new();
+    if (fg_color != NULL) {
+        if (0 > mazemaker_options_set_wall_color(options, fg_color)) {
+            fprintf(stderr, "Unknown color: \"%s\"\n", fg_color);
+            exit(1);
+        }
+    }
+    if (bg_color != NULL) {
+        if (0 > mazemaker_options_set_background_color(options, bg_color)) {
+            fprintf(stderr, "Unknown color: \"%s\"\n", bg_color);
+            exit(1);
+        }
+    }
     mazemaker_generate_maze(width, height, &maze);
-    mazemaker_maze_to_png(&maze, filename);
+    mazemaker_maze_to_png_opt(&maze, filename, options);
     mazemaker_free_maze(&maze);
+    mazemaker_options_free(options);
     poptFreeContext(ctx);
 }