make snprintf shared; dynamic resolution support

4 files changed, 18 insertions, 9 deletions

diff --git a/src/kernel/arch/amd64/boot.c b/src/kernel/arch/amd64/boot.c
index 570cebb..2707223 100644
--- a/src/kernel/arch/amd64/boot.c
+++ b/src/kernel/arch/amd64/boot.c
@@ -52,6 +52,7 @@ void kmain_early(struct multiboot_info *multiboot) {
 	vid.width  = multiboot->framebuffer_width;
 	vid.height = multiboot->framebuffer_height;
 	vid.bpp    = multiboot->framebuffer_bpp;
+	vid.size   = vid.pitch * vid.height;
 
 	kprintf("framebuffer at 0x%x, %ux%u bpp %u\n", vid.b, vid.width, vid.height, vid.bpp);
 	video_init(vid);
diff --git a/src/kernel/arch/amd64/driver/video.c b/src/kernel/arch/amd64/driver/video.c
index 2d1ac03..d22adc4 100644
--- a/src/kernel/arch/amd64/driver/video.c
+++ b/src/kernel/arch/amd64/driver/video.c
@@ -5,8 +5,12 @@
 #include <kernel/mem/virt.h>
 #include <kernel/panic.h>
 #include <kernel/vfs/request.h>
+#include <shared/mem.h>
+#include <shared/printf.h>
 
 static struct fb_info fb;
+static char namebuf[64];
+static size_t namelen;
 
 enum {
 	H_ROOT,
@@ -16,9 +20,10 @@ enum {
 static int handle(struct vfs_request *req) {
 	switch (req->type) {
 		case VFSOP_OPEN:
+			if (!req->input.kern) panic_invalid_state();
 			if (req->input.len == 1) {
 				return H_ROOT;
-			} else if (req->input.len == 2 && req->input.kern && req->input.buf_kern[1] == 'b') {
+			} else if (req->input.len == namelen + 1 && !memcmp(req->input.buf_kern + 1, namebuf, namelen)) {
 				return H_FB;
 			} else {
 				return -1;
@@ -26,26 +31,26 @@ static int handle(struct vfs_request *req) {
 
 		case VFSOP_READ:
 			if (req->id == H_ROOT) {
-				// TODO list available modes, e.g /640x480x24
-				const char src[] = "b";
-				return req_readcopy(req, src, sizeof src);
+				return req_readcopy(req, namebuf, namelen + 1);
 			} else {
-				return req_readcopy(req, fb.b, fb.pitch * fb.height);
+				return req_readcopy(req, fb.b, fb.size);
 			}
 
 		case VFSOP_WRITE:
 			if ((long)req->id != H_FB) {
 				return -1;
 			}
-			fs_normslice(&req->offset, &req->input.len, fb.pitch * fb.height, false);
+			fs_normslice(&req->offset, &req->input.len, fb.size, false);
 			if (!virt_cpy_from(req->caller->pages, fb.b + req->offset,
 					req->input.buf, req->input.len))
 			{
-				panic_invalid_state();
 				return -EFAULT;
 			}
 			return req->input.len;
 
+		case VFSOP_GETSIZE:
+			return fb.size;
+
 		default:
 			return -1;
 	}
@@ -67,5 +72,7 @@ static bool is_ready(struct vfs_backend *self) {
 static struct vfs_backend backend = BACKEND_KERN(is_ready, accept);
 void video_init(struct fb_info fb_) {
 	fb = fb_;
+	snprintf(namebuf, sizeof namebuf, "%ux%ux%u", fb.width, fb.height, fb.bpp);
+	namelen = strlen(namebuf);
 	vfs_mount_root_register("/video", &backend);
 }
diff --git a/src/kernel/arch/amd64/driver/video.h b/src/kernel/arch/amd64/driver/video.h
index c1680c4..dfc1710 100644
--- a/src/kernel/arch/amd64/driver/video.h
+++ b/src/kernel/arch/amd64/driver/video.h
@@ -5,6 +5,7 @@ struct fb_info {
 	char *b;
 	uint32_t width, height;
 	uint32_t pitch; /* width in bytes of a single scanline */
+	size_t size;
 	uint8_t bpp;
 };
 
diff --git a/src/kernel/arch/amd64/multiboot.s b/src/kernel/arch/amd64/multiboot.s
index c809297..4af0cd0 100644
--- a/src/kernel/arch/amd64/multiboot.s
+++ b/src/kernel/arch/amd64/multiboot.s
@@ -15,6 +15,6 @@ multiboot_header:
 	.skip 5 * 4
 
 	.long 0
-	.long 640
-	.long 480
 	.long 0
+	.long 0
+	.long 32