feat(config): 添加配置窗口边框 API

src/base/color.c

@@ -0,0 +1,107 @@
+#include "color.h"
+
+#include <stddef.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+
+#include "base/log.h"
+
+/**
+ * @brief 将 16 进制的颜色配置转换成 uint32 格式的 rgba数据
+ *
+ * @param hex 16 进制的颜色表示，支持的格式有
+ * RGB/RGBA/RRGGBB/RRGGBBAA/#RGB/#RGBA/#RRGGBB/#RRGGBBAA
+ * @param rgba 返回数据的指针，解析结果会放到这个指针指向的内存中
+ * @return 如果 hex 是一个能正常解析的颜色，返回 true ，否则返回 false
+ */
+static bool hex_color_to_rgba(const char *hex, uint32_t *rgba);
+/**
+ * @brief 将 rgba 通道顺序的颜色转换成 argb 顺序
+ * @description xcb 库用到的颜色需要是 argb 通道顺序
+ */
+static uint32_t rgba_to_argb(uint32_t rgba);
+/**
+ * @brief 提取颜色中的各个颜色通道数值
+ * @param rgba uint32 表示的颜色
+ * @param red red channel, range 0~1
+ * @param green green channel, range 0~1
+ * @param blue blue channel, range 0~1
+ * @param alpha alpha channel, range 0~1
+ */
+static void extract_color_channel(
+  const uint32_t rgba,
+  double *red,
+  double *green,
+  double *blue,
+  double *alpha
+);
+
+void color_parse(const char *hex, color_t *const color) {
+  bool success = hex_color_to_rgba(hex, &color->rgba);
+  if (!success) fatal("invalid hex color: %s", hex);
+
+  color->argb = rgba_to_argb(color->rgba);
+  extract_color_channel(
+    color->rgba,
+    &color->red,
+    &color->green,
+    &color->blue,
+    &color->alpha
+  );
+}
+
+bool hex_color_to_rgba(const char *hex, uint32_t *rgba) {
+  if (hex[0] == '#') hex++;
+
+  size_t len       = strlen(hex);
+  char extended[9] = {0};
+  uint32_t color   = 0x00000000;
+
+  if (len == 3 || len == 4) {
+    extended[0] = extended[1] = hex[0];
+    extended[2] = extended[3] = hex[1];
+    extended[4] = extended[5] = hex[2];
+    if (len == 3) {
+      extended[6] = extended[7] = 'F';
+    } else {
+      extended[6] = extended[7] = hex[3];
+    }
+  } else if (len == 6) {
+    strncpy(extended, hex, len);
+    extended[6] = extended[7] = 'F';
+  } else if (len == 8) {
+    strncpy(extended, hex, len);
+  } else {
+    return false;
+  }
+
+  color = strtoul(extended, nullptr, 16) & 0xffffffff;
+  *rgba = color;
+  return true;
+}
+
+#define EXTRACE_COLOR_BIT(C, R) (((C) >> (R)) & 0xff)
+uint32_t rgba_to_argb(uint32_t rgba) {
+  uint32_t r = EXTRACE_COLOR_BIT(rgba, 24);
+  uint32_t g = EXTRACE_COLOR_BIT(rgba, 16);
+  uint32_t b = EXTRACE_COLOR_BIT(rgba, 8);
+  uint32_t a = EXTRACE_COLOR_BIT(rgba, 0);
+
+  uint32_t argb = (a << 24) | (r << 16) | (g << 8) | b;
+  return argb;
+}
+
+#define COLOR_SPLIT(C, R) (EXTRACE_COLOR_BIT((C), (R)) / (double)0xff)
+void extract_color_channel(
+  const uint32_t rgba,
+  double *red,
+  double *green,
+  double *blue,
+  double *alpha
+) {
+  *red   = COLOR_SPLIT(rgba, 24);
+  *green = COLOR_SPLIT(rgba, 16);
+  *blue  = COLOR_SPLIT(rgba, 8);
+  *alpha = COLOR_SPLIT(rgba, 0);
+}

src/base/color.h

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <stdint.h>
+
+typedef struct color_t {
+  uint32_t rgba;
+  uint32_t argb;
+
+  /* RGBA color channels for Cairo, each channel in the range [0, 1] */
+  double red, green, blue, alpha;
+} color_t;
+
+/**
+ * @brief 解析 16 进制表示的颜色
+ *
+ * @param hex   颜色的 16 进制表示，支持的格式有
+ *              RGB/RGBA/RRGGBB/RRGGBBAA/#RGB/#RGBA/#RRGGBB/#RRGGBBAA
+ * @param color 存储颜色值的结构体指针，不能为 nullptr
+ */
+void color_parse(const char *hex, color_t *const color);