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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-14 13:40:54 +0000
commit317c0644ccf108aa23ef3fd8358bd66c2840bfc0 (patch)
treec417b3d25c86b775989cb5ac042f37611b626c8a /src/lolwut.c
parentInitial commit. (diff)
downloadredis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.tar.xz
redis-317c0644ccf108aa23ef3fd8358bd66c2840bfc0.zip
Adding upstream version 5:7.2.4.upstream/5%7.2.4
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/lolwut.c')
-rw-r--r--src/lolwut.c188
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diff --git a/src/lolwut.c b/src/lolwut.c
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+/*
+ * Copyright (c) 2018, Salvatore Sanfilippo <antirez at gmail dot com>
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * * Redistributions of source code must retain the above copyright notice,
+ * this list of conditions and the following disclaimer.
+ * * Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * * Neither the name of Redis nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without
+ * specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ *
+ * ----------------------------------------------------------------------------
+ *
+ * This file implements the LOLWUT command. The command should do something
+ * fun and interesting, and should be replaced by a new implementation at
+ * each new version of Redis.
+ */
+
+#include "server.h"
+#include "lolwut.h"
+#include <math.h>
+
+void lolwut5Command(client *c);
+void lolwut6Command(client *c);
+
+/* The default target for LOLWUT if no matching version was found.
+ * This is what unstable versions of Redis will display. */
+void lolwutUnstableCommand(client *c) {
+ sds rendered = sdsnew("Redis ver. ");
+ rendered = sdscat(rendered,REDIS_VERSION);
+ rendered = sdscatlen(rendered,"\n",1);
+ addReplyVerbatim(c,rendered,sdslen(rendered),"txt");
+ sdsfree(rendered);
+}
+
+/* LOLWUT [VERSION <version>] [... version specific arguments ...] */
+void lolwutCommand(client *c) {
+ char *v = REDIS_VERSION;
+ char verstr[64];
+
+ if (c->argc >= 3 && !strcasecmp(c->argv[1]->ptr,"version")) {
+ long ver;
+ if (getLongFromObjectOrReply(c,c->argv[2],&ver,NULL) != C_OK) return;
+ snprintf(verstr,sizeof(verstr),"%u.0.0",(unsigned int)ver);
+ v = verstr;
+
+ /* Adjust argv/argc to filter the "VERSION ..." option, since the
+ * specific LOLWUT version implementations don't know about it
+ * and expect their arguments. */
+ c->argv += 2;
+ c->argc -= 2;
+ }
+
+ if ((v[0] == '5' && v[1] == '.' && v[2] != '9') ||
+ (v[0] == '4' && v[1] == '.' && v[2] == '9'))
+ lolwut5Command(c);
+ else if ((v[0] == '6' && v[1] == '.' && v[2] != '9') ||
+ (v[0] == '5' && v[1] == '.' && v[2] == '9'))
+ lolwut6Command(c);
+ else
+ lolwutUnstableCommand(c);
+
+ /* Fix back argc/argv in case of VERSION argument. */
+ if (v == verstr) {
+ c->argv -= 2;
+ c->argc += 2;
+ }
+}
+
+/* ========================== LOLWUT Canvas ===============================
+ * Many LOLWUT versions will likely print some computer art to the screen.
+ * This is the case with LOLWUT 5 and LOLWUT 6, so here there is a generic
+ * canvas implementation that can be reused. */
+
+/* Allocate and return a new canvas of the specified size. */
+lwCanvas *lwCreateCanvas(int width, int height, int bgcolor) {
+ lwCanvas *canvas = zmalloc(sizeof(*canvas));
+ canvas->width = width;
+ canvas->height = height;
+ canvas->pixels = zmalloc((size_t)width*height);
+ memset(canvas->pixels,bgcolor,(size_t)width*height);
+ return canvas;
+}
+
+/* Free the canvas created by lwCreateCanvas(). */
+void lwFreeCanvas(lwCanvas *canvas) {
+ zfree(canvas->pixels);
+ zfree(canvas);
+}
+
+/* Set a pixel to the specified color. Color is 0 or 1, where zero means no
+ * dot will be displayed, and 1 means dot will be displayed.
+ * Coordinates are arranged so that left-top corner is 0,0. You can write
+ * out of the size of the canvas without issues. */
+void lwDrawPixel(lwCanvas *canvas, int x, int y, int color) {
+ if (x < 0 || x >= canvas->width ||
+ y < 0 || y >= canvas->height) return;
+ canvas->pixels[x+y*canvas->width] = color;
+}
+
+/* Return the value of the specified pixel on the canvas. */
+int lwGetPixel(lwCanvas *canvas, int x, int y) {
+ if (x < 0 || x >= canvas->width ||
+ y < 0 || y >= canvas->height) return 0;
+ return canvas->pixels[x+y*canvas->width];
+}
+
+/* Draw a line from x1,y1 to x2,y2 using the Bresenham algorithm. */
+void lwDrawLine(lwCanvas *canvas, int x1, int y1, int x2, int y2, int color) {
+ int dx = abs(x2-x1);
+ int dy = abs(y2-y1);
+ int sx = (x1 < x2) ? 1 : -1;
+ int sy = (y1 < y2) ? 1 : -1;
+ int err = dx-dy, e2;
+
+ while(1) {
+ lwDrawPixel(canvas,x1,y1,color);
+ if (x1 == x2 && y1 == y2) break;
+ e2 = err*2;
+ if (e2 > -dy) {
+ err -= dy;
+ x1 += sx;
+ }
+ if (e2 < dx) {
+ err += dx;
+ y1 += sy;
+ }
+ }
+}
+
+/* Draw a square centered at the specified x,y coordinates, with the specified
+ * rotation angle and size. In order to write a rotated square, we use the
+ * trivial fact that the parametric equation:
+ *
+ * x = sin(k)
+ * y = cos(k)
+ *
+ * Describes a circle for values going from 0 to 2*PI. So basically if we start
+ * at 45 degrees, that is k = PI/4, with the first point, and then we find
+ * the other three points incrementing K by PI/2 (90 degrees), we'll have the
+ * points of the square. In order to rotate the square, we just start with
+ * k = PI/4 + rotation_angle, and we are done.
+ *
+ * Of course the vanilla equations above will describe the square inside a
+ * circle of radius 1, so in order to draw larger squares we'll have to
+ * multiply the obtained coordinates, and then translate them. However this
+ * is much simpler than implementing the abstract concept of 2D shape and then
+ * performing the rotation/translation transformation, so for LOLWUT it's
+ * a good approach. */
+void lwDrawSquare(lwCanvas *canvas, int x, int y, float size, float angle, int color) {
+ int px[4], py[4];
+
+ /* Adjust the desired size according to the fact that the square inscribed
+ * into a circle of radius 1 has the side of length SQRT(2). This way
+ * size becomes a simple multiplication factor we can use with our
+ * coordinates to magnify them. */
+ size /= 1.4142135623;
+ size = round(size);
+
+ /* Compute the four points. */
+ float k = M_PI/4 + angle;
+ for (int j = 0; j < 4; j++) {
+ px[j] = round(sin(k) * size + x);
+ py[j] = round(cos(k) * size + y);
+ k += M_PI/2;
+ }
+
+ /* Draw the square. */
+ for (int j = 0; j < 4; j++)
+ lwDrawLine(canvas,px[j],py[j],px[(j+1)%4],py[(j+1)%4],color);
+}