make snprintf shared; dynamic resolution support

10 files changed, 98 insertions, 46 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
diff --git a/src/shared/mem.h b/src/shared/mem.h
index 8c83f2f..aac87f5 100644
--- a/src/shared/mem.h
+++ b/src/shared/mem.h
@@ -1,4 +1,5 @@
 #pragma once
+#include <stdarg.h>
 #include <stddef.h>
 
 /* note: (partially) tested in the userland tests */
@@ -11,3 +12,6 @@ void *memset(void *s, int c, size_t n);
 
 int strcmp(const char *s1, const char *s2);
 size_t strlen(const char *s);
+
+int snprintf(char *restrict str, size_t len, const char *restrict fmt, ...);
+int vsnprintf(char *restrict str, size_t len, const char *restrict fmt, va_list ap);
diff --git a/src/shared/printf.c b/src/shared/printf.c
index c1206f3..2dc3048 100644
--- a/src/shared/printf.c
+++ b/src/shared/printf.c
@@ -1,6 +1,7 @@
-#include <stdbool.h>
 #include <shared/mem.h>
 #include <shared/printf.h>
+#include <stdarg.h>
+#include <stdbool.h>
 
 struct out_state {
 	void (*back)(void *, const char *, size_t);
@@ -165,3 +166,31 @@ int __printf_internal(const char *fmt, va_list argp,
 		seg = fmt;
 	}
 }
+
+
+static void vsnprintf_backend(void *arg, const char *buf, size_t len) {
+	char **ptrs = arg;
+	size_t space = ptrs[1] - ptrs[0];
+	if (len > space) len = space;
+
+	memcpy(ptrs[0], buf, len);
+	ptrs[0] += len;
+	/* ptrs[1] is the last byte of the buffer, it must be 0.
+	 * on overflow:
+	 *   ptrs[0] + (ptrs[1] - ptrs[0]) = ptrs[1] */
+	*ptrs[0] = '\0';
+}
+
+int vsnprintf(char *restrict str, size_t len, const char *restrict fmt, va_list ap) {
+	char *ptrs[2] = {str, str + len - 1};
+	return __printf_internal(fmt, ap, vsnprintf_backend, &ptrs);
+}
+
+int snprintf(char *restrict str, size_t len, const char *restrict fmt, ...) {
+	int ret;
+	va_list argp;
+	va_start(argp, fmt);
+	ret = vsnprintf(str, len, fmt, argp);
+	va_end(argp);
+	return ret;
+}
diff --git a/src/user/app/vterm/vterm.c b/src/user/app/vterm/vterm.c
index 0468477..43180b2 100644
--- a/src/user/app/vterm/vterm.c
+++ b/src/user/app/vterm/vterm.c
@@ -1,7 +1,10 @@
 #include "vterm.h"
 #include <camellia/syscalls.h>
 #include <stdbool.h>
+#include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
 
 struct point cursor = {0};
 
@@ -26,15 +29,50 @@ void in_char(char c) {
 	while (cursor.y * font.h >= fb.height) scroll();
 }
 
-int main(void) {
-	fb_fd = _syscall_open("/kdev/video/b", 13, 0);
-	// TODO don't hardcode size
-	fb.len = 640 * 480 * 4;
-	fb.width = 640;
-	fb.height = 480;
-	fb.pitch = 640 * 4;
+int main();
+
+void fb_setup(void) {
+	#define BASEPATH "/kdev/video/"
+	char path[64], *spec;
+	size_t pos;
+	FILE *f;
+
+	f = fopen(BASEPATH, "r");
+	if (!f) {
+		eprintf("couldn't open %s", BASEPATH);
+		exit(1);
+	}
+
+	pos = strlen(BASEPATH);
+	memcpy(path, BASEPATH, pos);
+	spec = path + pos;
+	fread(spec, 1, sizeof(path) - pos, f);
+	/* assumes the read went correctly */
+	fclose(f);
+
+	fb_fd = _syscall_open(path, strlen(path), 0);
+	if (fb_fd < 0) {
+		eprintf("failed to open %s", path);
+		exit(1);
+	}
+
+	fb.width  = strtol(spec, &spec, 0);
+	if (*spec++ != 'x') { eprintf("bad filename format"); exit(1); }
+	fb.height = strtol(spec, &spec, 0);
+	if (*spec++ != 'x') { eprintf("bad filename format"); exit(1); }
+	fb.bpp = strtol(spec, &spec, 0);
+	fb.len = _syscall_getsize(fb_fd);
+	fb.pitch = fb.len / fb.height;
 	fb.b = malloc(fb.len);
 
+	if (fb.bpp != 32) {
+		eprintf("unsupported format %ux%ux%u", fb.width, fb.height, fb.bpp);
+		exit(1);
+	}
+}
+
+int main(void) {
+	fb_setup();
 	font_load("/init/font.psf");
 
 	static char buf[512];
diff --git a/src/user/app/vterm/vterm.h b/src/user/app/vterm/vterm.h
index 5e09105..5cfc609 100644
--- a/src/user/app/vterm/vterm.h
+++ b/src/user/app/vterm/vterm.h
@@ -24,6 +24,7 @@ void font_blit(uint32_t glyph, int x, int y);
 
 struct framebuf {
 	size_t len, width, height, pitch;
+	uint8_t bpp;
 	char *b;
 };
 extern struct framebuf fb;
diff --git a/src/user/lib/include/stdio.h b/src/user/lib/include/stdio.h
index 063c81f..4d9cf94 100644
--- a/src/user/lib/include/stdio.h
+++ b/src/user/lib/include/stdio.h
@@ -11,11 +11,9 @@
 
 int printf(const char *restrict fmt, ...);
 int fprintf(FILE *restrict f, const char *restrict fmt, ...);
-int snprintf(char *restrict str, size_t len, const char *restrict fmt, ...);
 
 int vprintf(const char *restrict fmt, va_list ap);
 int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap);
-int vsnprintf(char *restrict str, size_t len, const char *restrict fmt, va_list ap);
 
 int _klogf(const char *fmt, ...); // for kernel debugging only
 
diff --git a/src/user/lib/printf.c b/src/user/lib/printf.c
index 53b1140..cb6561b 100644
--- a/src/user/lib/printf.c
+++ b/src/user/lib/printf.c
@@ -12,24 +12,6 @@ int vfprintf(FILE *restrict f, const char *restrict fmt, va_list ap) {
 	return __printf_internal(fmt, ap, backend_file, f);
 }
 
-static void backend_buf(void *arg, const char *buf, size_t len) {
-	char **ptrs = arg;
-	size_t space = ptrs[1] - ptrs[0];
-	if (len > space) len = space;
-
-	memcpy(ptrs[0], buf, len);
-	ptrs[0] += len;
-	/* ptrs[1] is the last byte of the buffer, it must be 0.
-	 * on overflow:
-	 *   ptrs[0] + (ptrs[1] - ptrs[0]) = ptrs[1] */
-	*ptrs[0] = '\0';
-}
-
-int vsnprintf(char *restrict str, size_t len, const char *restrict fmt, va_list ap) {
-	char *ptrs[2] = {str, str + len - 1};
-	return __printf_internal(fmt, ap, backend_buf, &ptrs);
-}
-
 
 int printf(const char *restrict fmt, ...) {
 	int ret;
@@ -49,15 +31,6 @@ int fprintf(FILE *restrict f, const char *restrict fmt, ...) {
 	return ret;
 }
 
-int snprintf(char *restrict str, size_t len, const char *restrict fmt, ...) {
-	int ret;
-	va_list argp;
-	va_start(argp, fmt);
-	ret = vsnprintf(str, len, fmt, argp);
-	va_end(argp);
-	return ret;
-}
-
 int vprintf(const char *restrict fmt, va_list ap) {
 	return vfprintf(stdout, fmt, ap);
 }