misc + change license + remove info manual1.3.2

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 183 insertions, 0 deletions

diff --git a/framebuffer.c b/framebuffer.c
new file mode 100644
index 0000000..29459ac
--- /dev/null
+++ b/framebuffer.c
@@ -0,0 +1,183 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+/**
+ * The psuedodevice pathname pattern used to access a framebuffer
+ */
+#ifndef FB_DEVICE_PATTERN
+# define FB_DEVICE_PATTERN  "/dev/fb%lu"
+#endif
+
+
+/**
+ * The number of elements to allocates to a buffer for a framebuffer device pathname
+ */
+#define FB_DEVICE_MAX_LEN (sizeof(FB_DEVICE_PATTERN) / sizeof(char) + 3 * sizeof(size_t))
+
+
+
+/**
+ * Figure out how many framebuffers there are on the system
+ * 
+ * @return  The number of framebuffers on the system
+ */
+size_t
+fb_count(void)
+{
+	char buf[FB_DEVICE_MAX_LEN];
+	size_t count = 0;
+  
+	for (;; count++) {
+		sprintf(buf, FB_DEVICE_PATTERN, count);
+		if (access(buf, F_OK) < 0)
+			return count;
+	}
+}
+
+
+/**
+ * Open a framebuffer
+ * 
+ * @param   index  The index of the framebuffer to open
+ * @param   fb     Framebuffer information to fill in
+ * @return         Zero on success, -1 on error
+ */
+int
+fb_open(size_t index, framebuffer_t *restrict fb)
+{
+	char buf[FB_DEVICE_MAX_LEN];
+	struct fb_fix_screeninfo fix_info;
+	struct fb_var_screeninfo var_info;
+	int old_errno;
+
+	fb->fd = -1;
+	fb->mem = MAP_FAILED;
+
+	sprintf(buf, FB_DEVICE_PATTERN, index);
+	fb->fd = open(buf, O_RDWR);
+	if (fb->fd < 0)
+		goto fail;
+
+	if (ioctl(fb->fd, (unsigned long int)FBIOGET_FSCREENINFO, &fix_info) ||
+	    ioctl(fb->fd, (unsigned long int)FBIOGET_VSCREENINFO, &var_info))
+		goto fail;
+
+	fb->mem = mmap(NULL, (size_t)(fix_info.smem_len), PROT_WRITE, MAP_SHARED, fb->fd, (off_t)0);
+	if (fb->mem == MAP_FAILED)
+		goto fail;
+
+	fb->mem += var_info.xoffset * (var_info.bits_per_pixel / 8);
+	fb->mem += var_info.yoffset * fix_info.line_length;
+
+	fb->width           = var_info.xres;
+	fb->height          = var_info.yres;
+	fb->bytes_per_pixel = var_info.bits_per_pixel / 8;
+	fb->line_length     = fix_info.line_length;
+
+	return 0;
+fail:
+	old_errno = errno;
+	fb_close(fb);
+	errno = old_errno;
+	return -1;
+}
+
+
+/**
+ * Close a framebuffer
+ * 
+ * @param  fb  The framebuffer information
+ */
+void
+fb_close(framebuffer_t *restrict fb)
+{
+	if (fb->fd >= 0) {
+		close(fb->fd);
+		fb->fd = -1;
+	}
+}
+
+
+/**
+ * Construct an sRGB colour in 32-bit XRGB encoding to
+ * use when specifying colours
+ * 
+ * @param   red    The red   component from [0, 255] sRGB
+ * @param   green  The green component from [0, 255] sRGB
+ * @param   blue   The blue  component from [0, 255] sRGB
+ * @return         The colour as one 32-bit integer
+ */
+uint32_t
+fb_colour(int red, int green, int blue)
+{
+	uint32_t rc = 0;
+	rc |= (uint32_t)red,   rc <<= 8;
+	rc |= (uint32_t)green, rc <<= 8;
+	rc |= (uint32_t)blue;
+	return rc;
+}
+
+
+/**
+ * Print a filled in rectangle to a framebuffer
+ * 
+ * @param  fb      The framebuffer
+ * @param  colour  The colour to use when drawing the rectangle
+ * @param  x       The starting pixel on the X axis for the rectangle
+ * @param  y       The starting pixel on the Y axis for the rectangle
+ * @param  width   The width of the rectangle, in pixels
+ * @param  height  The height of the rectangle, in pixels
+ */
+void
+fb_fill_rectangle(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t width, uint32_t height)
+{
+	int8_t *mem = fb->mem + y * fb->line_length;
+	size_t x1 = x * fb->bytes_per_pixel;
+	size_t x2 = (x + width) * fb->bytes_per_pixel;
+	size_t y2 = y + height;
+	size_t x_, y_;
+	for (y_ = y; y_ != y2; y_++, mem += fb->line_length)
+		for (x_ = x1; x_ != x2; x_ += fb->bytes_per_pixel)
+			*(uint32_t *)&mem[x_] = colour;
+}
+
+
+/**
+ * Draw a horizontal line segment on a framebuffer
+ * 
+ * @param  fb      The framebuffer
+ * @param  colour  The colour to use when drawing the rectangle
+ * @param  x       The starting pixel on the X axis for the line segment
+ * @param  y       The starting pixel on the Y axis for the line segment
+ * @param  length  The length of the line segment, in pixels
+ */
+void fb_draw_horizontal_line(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t length)
+{
+	int8_t *mem = fb->mem + y * fb->line_length;
+	size_t x1 = x * fb->bytes_per_pixel;
+	size_t x2 = (x + length) * fb->bytes_per_pixel;
+	size_t x_;
+	for (x_ = x1; x_ != x2; x_ += fb->bytes_per_pixel)
+		*(uint32_t *)&mem[x_] = colour;
+}
+
+
+/**
+ * Draw a vertical line segment on a framebuffer
+ * 
+ * @param  fb      The framebuffer
+ * @param  colour  The colour to use when drawing the rectangle
+ * @param  x       The starting pixel on the X axis for the line segment
+ * @param  y       The starting pixel on the Y axis for the line segment
+ * @param  length  The length of the line segment, in pixels
+ */
+void fb_draw_vertical_line(framebuffer_t *restrict fb, uint32_t colour, uint32_t x, uint32_t y, uint32_t length)
+{
+	int8_t *mem = fb->mem + y * fb->line_length + x * fb->bytes_per_pixel;
+	size_t y2 = y + length;
+	size_t y_;
+
+	for (y_ = y; y_ != y2; y_++, mem += fb->line_length)
+		*(uint32_t *)mem = colour;
+}